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Industrial Intelligence, Engineered

From plant-floor telemetry
to closed-loop economic value.

Axiom Process Technology works on one question: can this operation prove what it believes about itself? We establish what the instruments underneath a decision are actually capable of supporting, we say plainly where the evidence will not carry the weight being put on it, and we build control, detection and reporting only on what survives that test. Every controller and every alarm earns its place against numbers the operating team can defend, every shift, on the screens that actually run the plant.

Open-Pit Mining PGM Concentration Chrome Concentration Ferrochrome Smelting SAG and Ball Milling Flotation Circuits Leaching and Adsorption Tailings Storage Facilities Thickening and Dewatering Submerged-Arc Furnaces Soderberg Electrode Control Energy and Utilities Process Manufacturing Predictive Maintenance Digital Twins
+3%
PGM recovery upliftAchieved · PGM · 2025 · measured against a signed baseline
Signed
Every engagement opens on a countersigned performance baseline before a controller is builtMethod, not outcome
≥85%
Soft sensor accuracy floor, R² on held-out future periods, before sign-off for control usePublished standard we hold ourselves to
Cited
Retrieval systems answer from OEM manuals and SOPs with the source shown, so an artisan can check the answerMethod, not outcome
15+ yrs
Plant-floor metallurgy, instrumentation and controlTeam experience
6
Heavy industry sectors covered, each with its own capability pageScope of practice
What We Do

Operating excellence is an
intelligence problem first.

We close the distance between raw process data and the high-value decisions that move throughput, recovery, and unit cost. Every engagement opens on a signed baseline and closes on a system the operating team owns, runs, and continues to evolve.

01 / CONTROL
Hybrid Advanced Process Control
Custom hybrid Fuzzy Logic and Model Predictive Control fused to handle non-linear circuit behaviour, fast disturbance rejection, and global constraint optimisation in one auditable architecture.
02 / SENSING
Physics-Informed Soft Sensors
Grey-box virtual instrumentation for grade, particle size, electrode immersion, off-gas chemistry, and other states where direct measurement is absent or unreliable. Mass and energy balances anchor every prediction.
03 / ASSETS
Predictive Maintenance and Digital Twins
Probabilistic remaining-useful-life forecasting and physics-informed dynamic twins. Scenario testing, virtual commissioning, and operator training carried out against a faithful synchronised replica of the plant.
04 / TAILINGS
Tailings Storage Facility Management
Instrumented management of the tailings stream from thickener underflow to decant return. Pore pressure, deformation, seepage and water balance carried as live measured states, with a purpose-built anomaly detection stack and reporting aligned to the Global Industry Standard on Tailings Management.
Real-time geotechnical telemetry and InSAR deformation Automated TARP escalation with a full audit trail
05 / READINESS
A Six-Phase Delivery Discipline
Business understanding, then data understanding, then build, commission, deploy and monitor the value. Three hard gates sit inside the first two phases, covering instrumentation, base control layer, historian quality, network security and organisational readiness. A gate that fails stops the engagement, in writing.
06 / DATA
Edge-to-Cloud Telemetry Platforms
Field gateways, industrial message brokers, time-series and spatial stores, and governed analytics. Built so an outage delays data rather than losing it, and so every automated output can be reproduced from its raw inputs.
About Us

An industrial intelligence consultancy
built on the plant floor.

Axiom Process Technology is a South African industrial intelligence firm operating at the absolute intersection of mining, metallurgy, process control, data science, and machine learning. Boutique by design, accountable by engineering discipline, and committed to leaving every operating team more capable than we found it.

Axiom was founded at the intersection that generic AI vendors and traditional control houses both miss. AI vendors treat process operations as a commodity data problem and stall on the plant floor. Traditional control houses lack the modern machine-learning depth to convert sensor abundance into closed-loop economic value. The intersection is where the work actually lives, and the first question we ask there is not which model to build. It is whether the instruments the decision rests on are telling the truth, because a control layer built on an unverified measurement inherits the error and then hides it behind a confident number. Once that is established, what we build is a five-layer control architecture: a healthy DCS at the foundation, gated by a formal Control Readiness check; an anomaly detection layer guarding it against sensor dropout, sticky valves, and dead-banded transmitters; soft sensors converting opaque process states into continuously controllable signals; an Advanced Process Control layer above them; and an AI Optimisation Layer at the top, recommending setpoints the operating team accepts or rejects.

The architecture is applied where it earns its place. The APC layer stabilises metallurgical operations: crushing, milling, comminution, flotation, and pyrometallurgy circuits, where multivariable control and feedforward soft sensors compound into measurable throughput, recovery, and energy gains. In energy and utilities, the same optimisation layer schedules specific energy consumption against tariff structure, demand limits and self-generation, treating energy as a constraint inside the process problem rather than as a separate system beside it. In manufacturing, the soft sensors and APC layer hold quality, yield and throughput across the production line, most closely where the process is continuous or batch and the physics resembles the circuits this practice was built on. Reliability engineering runs in parallel on the asset side of every operation, contributing probabilistic Remaining Useful Life forecasting, condition monitoring, computer-vision inspection, and risk-weighted CAPEX planning.

Every engagement begins with a site team's question, not an algorithm's offer. We build soft sensors from the plant's most valuable existing asset, its historian, alongside the SCADA tags, periodic laboratory assays, and maintenance records the operation already produces. No CAPEX push means we never propose instrumentation to make our own product work. Where the physics of a control objective requires a measurement that does not exist, we say so plainly. We attempt the inferential route first and report honestly whether the estimate clears our published accuracy floor. If it does not, we scope a smaller control objective in preference to forcing the spend. The decision to instrument is always the operation's, and it is made against a number we have published rather than a claim we have asserted. We cannot sell you a sensor, a mill, a filter press, grinding media, a flotation cell or a DCS, because we make none of them, and there is no product line, distribution agreement or commission arrangement anywhere in this business against which a recommendation could be written. The deliverable is never a slide deck. The deliverable is a system the operating team owns and continues to evolve.

Plant-Floor Provenance
Over fifteen years on-site with metallurgists, operators, and instrumentation technicians. Theory earns its place only when operating reality confirms it.
Physics-Informed Discipline
Mass, energy, and hydrodynamic balances form the backbone of every soft sensor and controller we ship to production.
Signed Performance Baselines
Every claim is held against a numerical baseline countersigned before commissioning. Value is measured, never merely asserted.
Client Ownership By Design
Knowledge transfer is engineered into the engagement. The client owns the models, the runbooks, and the right to evolve them independently.
/ Operating Discipline at a Glance
Domain experience15+ yrs
Sectors covered6
PGM recovery upliftAchieved · PGM · 2025 · signed baseline+3%
EY AI and Data ChallengeRanked 20261st in Africa
Model classGrey-Box
Engagement modelOwned
Our work is judged on the trading floor of operations, not the slide deck. If a controller cannot hold its target against the historian, it does not ship.
/ Axiom Operating Principle
Our Team

Multidisciplinary,
by deliberate design.

The Axiom leadership team operates at the exact intersection of mining, metallurgy, multi-disciplinary engineering, machine learning, and applied artificial intelligence. Senior practitioners with hands-on plant credentials, not consultants briefed at the airport. Deliverables carrying an engineering judgement are signed by a named engineer.

/ Chief Executive Officer
Ditebogo Mthimunye
Chief Executive Officer

A chemical engineer with fifteen years of operating experience across the southern African mining industry. Ditebogo has held metallurgical roles at major PGM, base metal, and diamond producers, including an appointment as Technical Assistant to a Group Chief Operating Officer. As a senior consultant she led commodity market studies, techno-financial modelling, scenario analysis, and capital-grade business case development. She is also the founding Managing Director of Marula MM Resources.

Chemical Engineering 15+ Years PGM · Base Metals · Diamonds Techno-Financial Modelling MD, Marula MM Resources
/ Technical Director
Terrence Davhana
Technical Director

Leads the technical function at Axiom, owning engagement scoping through to the models and control strategies that go live in the control room. His work sits at the intersection of metallurgy, process control, machine learning, and data science. Physics-informed soft sensors feeding fuzzy logic and model predictive control across milling, flotation, and furnace circuits. Work he has led lifted PGM recovery by three percentage points in 2025, measured against a signed baseline, and stabilised energy intensity across multi-circuit chrome and PGM operations.

BTech Extraction Metallurgy PGDip Data Science, Stellenbosch Member, SAIMM +3% PGM Recovery, 2025, signed baseline 1st in Africa, EY 2026 15+ Years On-Site
/ Director, Pyrometallurgy
Helly Nkhuna
Director, Pyrometallurgy

Nineteen years across flotation, smelting and plant operations in the southern African mining industry. Helly started as a field metallurgist on reagent performance and flotation optimisation, then moved to the reagent supply side in vendor management. At Rio Tinto Richards Bay Minerals he held process metallurgy roles across the smelter and the final product plant, covering furnace operation, electrode consumption, slag chemistry and freeze lining integrity, before appointment as plant superintendent with responsibility for metallurgical accounting, bottleneck resolution and shutdown planning. He owns the pyrometallurgy practice at Axiom, and holds a senior technical role at Masingita Group.

Master’s, Pyrometallurgy, UJ BTech Metallurgy BCom Quantitative Management Six Sigma Green Belt Furnace · Smelting · Flotation 19 Years On-Site
Who We Cover

Six sectors,
one engineering philosophy.

From the open pit through the concentrator and the furnace to the tailings facility that holds what is left, the platform meets each sector with discipline calibrated to its physics, its risk profile, and its operating cadence. We do not generalise across industries. We specialise inside them.

01 / Fleet and Asset Intelligence

Mining

Surface and underground operations generate vast quantities of fragmented maintenance data: inspection records, ERP exports, OEM documentation, telemetry from haul fleets, drill rigs, and conveyor systems. We consolidate this into actionable fleet intelligence so maintenance and engineering teams can manage assets proactively. Predictive maintenance, remaining useful life forecasting, fleet utilisation analytics, and automated risk referral all integrate with the existing CMMS and historian.
Calibrated
Failure probability stated as a distribution, not a date
Sensor-optional
First-day value from maintenance records alone
02 / Advanced Process Control

Mineral Processing

Shifts in mineralogy, fluctuating feed grades, and varying particle size distributions constantly threaten the economic sweet spot. When a circuit encounters a disturbance, operators react manually, often overcorrecting and driving variance into the next downstream unit. The Axiom hybrid Fuzzy Logic and Model Predictive Control framework removes that variance and holds the circuit at its economic optimum automatically. Comminution, flotation, leaching, dewatering, and the tailings stream that leaves the circuit, engaged as the interfaces they physically are. This sector is served by three capability pages, because the control problems genuinely differ.
+3%
PGM recovery upliftAchieved · PGM · 2025 · signed baseline
Full circuit
Crushing to water reticulation as one coupled system
03 / Structural and Environmental Intelligence

Tailings Storage Facilities

A tailings facility is the only major structure on a mine that is built continuously, by the process plant, out of a material whose properties move with the ore. Design intent and the deposit that actually exists drift apart quietly, and the interval between readings is where that drift hides. Axiom instruments the chain from thickener underflow to decant return and carries pore pressure, deformation, seepage, deposition and water balance as live measured states, with a five-layer detection stack and reporting aligned to the Global Industry Standard on Tailings Management. Every engineering decision stays with the Engineer of Record.
Continuous
Facility observed between inspections, not only during them
5
Detection layers, instrument health to geotechnical stateArchitecture
04 / Furnace and Smelter Intelligence

Pyrometallurgy and Smelting

Submerged-arc furnaces, electric arc furnaces, and rotary-kiln pre-reduction circuits carry extreme thermal, electrical, and chemical complexity. Real-time intelligence in these environments directly determines energy intensity, electrode integrity, refractory life, and metal recovery. Furnace state estimation, resistance-based electrode control with slip and Soderberg baking management, and tariff-aware energy load shaping are an active focus of the practice.
State estimation
Electrode immersion and freeze lining carried as measured states
Tariff-aware
Energy load shaped against the tariff structure in force
05 / Load, Tariff and Asset Intelligence

Energy and Utilities

Energy is negotiated by one function and spent by another, and the intensity number in between is owned by neither. We carry specific energy as a controlled variable, maximum demand as a hard constraint, and time-of-use structure as a schedulable objective, handed to the same optimisation layer that runs the process rather than to a separate energy system alongside it. On the asset side, transformers, rotating plant and renewable installations are carried as a monitored population. Electrical design, protection and compliance remain with your electrical engineer.
Interval-aware
Metering checked against the interval the tariff settles on
One problem
Energy competes with throughput inside the same optimisation
06 / Production Intelligence

Manufacturing

The authoritative quality measurement usually arrives after the product exists, which means everything upstream runs on the assumption that the last good result still holds. We build inline quality estimators that move at the speed of the line, hold them to a published accuracy floor before they are allowed to change anything, and demote the laboratory from the thing that closes the loop to the thing that calibrates the estimator. Strongest on continuous and batch process, where the physics resembles the circuits this practice was built on.
Quality inferred
Soft sensing where inline quality measurement does not exist
OEE decomposed
Three components and a stated time basis, never the product alone
Corporate Identity

Vision, mission, purpose:
anchored in the word itself.

An axiom is a fundamental, self-evident truth. A rock-solid starting point from which every other truth can be derived. We chose the name because the discipline embedded in it describes precisely what we build for industrial operations: an unshakeable foundation of data-driven truth from which every downstream decision becomes mathematically justifiable.

/ Vision

The definitive global foundation for absolute, data-driven operating truth in heavy industry.

To establish Axiom as the standard against which industrial intelligence is measured. A future in which every heavy-industrial operation, from the open pit to the smelter to the manufacturing line, runs on a continuously verified, physics-informed source of operating truth. From that foundation, self-optimising, zero-loss operations stop being an aspiration and become an engineering inevitability.

/ Mission

Strip uncertainty out of complex industrial operations through first-principles engineering and hybrid process intelligence.

We deploy fundamental engineering first-principles, hybrid process intelligence, elite control loops, and digital twin frameworks to convert raw process data into closed-loop economic value. Mass, energy, and hydrodynamic balances govern every soft sensor we ship. Fuzzy Logic and Model Predictive Control hold targets that move throughput, recovery, and energy intensity. Every claim is held against a countersigned baseline. Unit costs go down, throughput and energy targets are hit, and the operating team owns the resulting system.

/ Purpose

Complex industrial variables can be mastered through indisputable, mathematically stable control.

The foundational why of the firm. We believe the most intricate thermodynamic, mechanical, and pyrometallurgical processes are not mysteries to be managed reactively. They are systems to be modelled, instrumented, and controlled with the same rigour as a structural engineering calculation. When industrial operations are governed by axiomatic truth rather than operator intuition, the boardroom-level outcomes (predictable cash flow, defensible unit costs, structurally lower risk) follow without negotiation.

Axiom, noun: A statement or proposition regarded as established, accepted, or self-evidently true. From the Greek axioma, that which is thought worthy or fit. The starting point of reasoning, from which all other truths are derived.
Axiom Capability

Our Framework

A six-phase delivery discipline

Understand the business.
Then the data. Then build.

Every Axiom engagement runs through the same six phases, in the same order, whether the asset is a concentrator, a furnace or a tailings storage facility. The order is deliberate and it is not negotiable, because each phase exists to prevent a specific and entirely predictable failure in the one after it.

The Core Problem

Most operations are data-rich,
yet insight-poor.

Generic data science firms do not understand the difference between a rougher and a cleaner circuit. They treat a flotation cell like an e-commerce funnel and ignore the hydrodynamic and kinetic realities that actually govern recovery. Conventional Advanced Process Control is frequently brittle. Rigid, linear models demand constant manual retuning whenever ore mineralogy shifts, and they sever the plant from enterprise data at the precise moment integration would deliver the most value.

Axiom resolves this tension. We speak both languages with equal fluency: deep domain physics and modern machine learning. We build physics-informed models that embed foundational physical boundaries directly into the learning architecture: comminution kinetics, flotation hydrodynamics, multiphase slag-melt thermodynamics, and continuum mechanics. By constraining the learned components to respect those balances, we integrate them with existing SCADA, DCS, and enterprise automation layers. Operational data becomes continuous, verifiable, and automated economic gain.

Where Generic AI Firms Fail
Where Traditional APC Stalls
The Axiom Architecture
Flotation cells are modelled like e-commerce funnels, ignoring hydrodynamic and kinetic realities.
Rigid linear models require constant manual retuning whenever ore mineralogy shifts.
Domain-Driven Architecture. Models constrained by mass, energy, and hydrodynamic balances, engineered to adapt autonomously to changing feed.
Python notebooks that sit on a shelf and never reach production.
Disconnected from modern cloud scale, creating data silos between plant and enterprise.
Edge-to-Cloud Integration. Scalable data engineering operating safely at the edge, writing validated setpoints back to your DCS.
No engineering accountability. If the model underperforms, nobody answers for it.
Operator adoption fails because the system is switched off the moment the plant moves outside nominal conditions.
Signed Baseline, Measured Outcomes. Every engagement opens with a countersigned performance reference. Value is measured, never merely claimed.
Why this sequence
We did not invent the order. We adapted a standard, then hardened it for live plant.

The backbone is CRISP-DM, the Cross Industry Standard Process for Data Mining, developed in the late 1990s and published as version 1.0 in 2000. It remains the most commonly cited reference process for analytics projects, and we use it for that reason rather than inventing a proprietary method with a memorable name. What we do add is the adaptation it never had, for an environment where the model writes setpoints to live equipment and being wrong costs production, safety and licence to operate.

Two things change in that adaptation. Commissioning becomes its own phase, because proving a model on a running plant with operators in the loop is a completely different activity from building it. And value monitoring becomes permanent rather than a closing report, because an industrial process keeps moving underneath a model long after the project team has gone home.

What each phase prevents
  • Skip business understanding and you optimise the wrong thing beautifully
  • Skip data understanding and the model inherits every bias in the instrument
  • Skip the build discipline and you get a notebook, not a system
And the ones people skip most
  • Skip commissioning and the operators switch it off in week three
  • Skip hand-over and you have bought a dependency, not a capability
  • Skip value monitoring and the gain is claimed, never proven, and it quietly decays
Phase
What happens
What closes it
01 / Business Understanding
Site teams, frustrations, flowsheet and P&IDs, TSF design and deposition plan, a red-pen walk of the physical asset.
A written problem statement and value hypothesis, agreed with the site.
02 / Data Understanding
Instrument audit, loop and controller integrity, historian quality, network and security. Three gates.
A formal Readiness Declaration and a countersigned baseline.
03 / Build the Axiom Workflow
Grey-box models, soft sensors, controllers and the detection stack, all exercised offline against a twin.
Validation on held-out future periods the model has never seen.
04 / Commissioning
Live on the operation in advisory mode, operators in control, alarm load tuned, teams trained.
A site acceptance test the operating team signs.
05 / Deployment
Closed loop on the team's decision, scale-out across the asset, full transfer of ownership.
Runbooks, registry and the right to evolve the system, in your hands.
06 / Monitor the Value
Value measured against the baseline, drift governed, calibration and loop health re-audited.
Nothing. This one runs for as long as the system does.
The Six Phases

One discipline,
two very different assets.

Each phase below is set out twice, because a concentrator and a tailings facility fail in different ways and need different evidence, even though the discipline that gets us there is identical.

Phase 01
Business Understanding
We start with the operation, not the dataset. A fortnight of structured conversation with the people who run the asset tells you more about where value sits than two years of history will. Everything learned here is written down and agreed before anyone opens a historian.
Skip it and you optimise the wrong thing beautifully. The most expensive failure in industrial analytics is a technically excellent model solving a problem nobody asked about.
Process understanding, before any data understanding
PFD Process Flow Diagram Unit operations, main streams, and the mass balance the plant was designed to deliver. Where we start, because it says what the circuit is for.
P&ID Piping and Instrumentation Every line, valve, transmitter and interlock. This is the drawing the control layer actually lives on, and the one we walk with a red pen.
Narrative Control Philosophy What each loop is meant to do, and the conditions under which it is meant to stop doing it. Frequently the document nobody has opened since commissioning.
PID Loop Register Every regulatory controller, its mode, its tuning and its history. Read here, then tested for real in Phase 02.
As-Built What We Hand Back The corrected drawing set, reconciled against the plant that exists rather than the plant that was designed. Yours to keep, whatever happens next.
Two of these share almost the same initials and we mean both of them. P&ID is the drawing. PID is the controller. The first tells us where the second is supposed to be, the walk tells us where it actually is, and Phase 02 tells us whether it is doing anything.
What we establish in this phase 12 checkpoints
On a concentrator or furnace
  • Metallurgists, plant manager, operators and C&I engaged separately, because they do not tell the same story
  • What has been tried, what failed, and where the frustration actually sits
  • A red-pen walk of the circuit against the drawings, producing a corrected as-built
  • A constraint and bottleneck register: what limits this operation today, and the evidence for each entry
  • An installed-but-idle asset register, because the fastest value is often something already paid for
  • Feed provenance: whether you can reconstruct what material ran when, and from where
On a tailings facility
  • Engineer of Record, Responsible Tailings Facility Engineer and site custodian engaged directly
  • Design report, raise method and deposition plan read before the first site visit
  • The failure modes already named in your risk assessment, and the TARP that sits over them
  • A physical walk of the wall, toe, decant and delivery line against the drawings
  • What instrumentation exists, who reads it, and whether anyone trusts it
  • How the water balance is currently understood, and where it does not close
Closes on A written problem statement and value hypothesis, plus a safety and licence-to-operate constraint register naming the regulatory, environmental and occupational limits you run against. Those become hard constraints in the optimisation layer. We establish the boundaries before we build anything capable of approaching them.
Phase 02
Data Understanding
A model is only ever as good as the measurement beneath it. This is a formal audit of whether the instruments, the base control layer, the historian and the network can carry what we intend to build. It contains three gates, and a gate that fails stops the engagement in writing until it is remediated.
Skip it and the model inherits every bias in the instrument. A flow element installed outside its OEM specification and long past calibration does not announce itself. It quietly poisons every model trained on it.
What we establish in this phase 11 checkpoints
On a concentrator or furnace
  • A six-point audit of every critical tag: calibration, installation geometry, signal path, deadband, sampling rate, physical condition
  • Loop health established rather than assumed: auto mode, valve response, cascade integrity, silent overrides
  • Controller integrity judged from the historian, not from the colour of a faceplate
  • Whether two years of history covers two years of operating envelope, or two years of one ore type
  • Laboratory and sampling integrity, because recovery and grade are laboratory numbers first
  • The route data takes out, agreed with IT and OT security in week one
On a tailings facility
  • The same audit applied to piezometers, weirs, level instruments and survey control
  • Whether the network resolves the sections your Engineer of Record considers governing, or only the ones that were easy to drill
  • Survey continuity: a common datum, and a stage-storage curve that still describes the facility
  • Whether the water balance closes, and by how much it does not
  • Where instrumentation is absent altogether, which is often the honest finding
Gate 01 A failing critical instrument is remediated before any data assessment proceeds.
Gate 02 We do not proceed on a broken base layer. A bypassed APC, PIDs in manual, broken cascades, alarms disabled on critical loops, undeclared correction factors on primary measurements, or controller outputs sitting at their limit will each fail this gate. Stability comes before optimisation, with no exceptions.
Gate 03 A formal Readiness Declaration across five dimensions: measurement, base control layer, data adequacy, organisational readiness, and metal and mass accounting. Pass means site ready, baseline agreed, proceed to build. Fail means a costed remediation plan handed to you. The diagnostic is not a delay. It is the investment that determines the return.
Phase 03
Build the Axiom Workflow
This is where the engineering happens, and it happens offline. Mass, energy and hydrodynamic balances form the backbone. Data-driven layers learn only what the physics does not capture. Everything is exercised against a simulation of the operation before it goes near live equipment.
Skip the discipline here and you get a notebook, not a system. A model tested only on its own training data will look excellent in a review and fail in the first month of the wet season.
What we establish in this phase 10 checkpoints
On a concentrator or furnace
  • Grey-box construction: a first-principles core with data-driven residual layers on top
  • Soft sensors for the states the plant cannot measure, controllers for the loops it cannot hold
  • Validation on held-out future periods, never on the data the model was trained on
  • Performance reported stratified by mode and feed type, with calibrated uncertainty
  • A digital twin exercised across the operating envelope before anything touches the plant
On a tailings facility
  • The five-layer detection stack configured to your facility rather than to a template
  • Physical balances closed and thresholds set from your own data, not a vendor default
  • Detection thresholds mapped onto your TARP levels with the Engineer of Record in the room
  • Phreatic surface reconstruction validated against the design surface and manual dip readings
  • False-alarm rate estimated on history before a single alarm reaches a person
Phase 04
Commissioning
The system runs live, in advisory mode, with your team deciding whether to accept anything it recommends. Performance is tracked against the signed baseline on a dashboard everyone can see. This is also where the alarm load is tuned down to something a control room can genuinely carry.
Skip it and the operators switch it off in week three. Every system bypassed on an industrial site was bypassed by someone who did not trust it and had no way to check it.
What we establish in this phase 10 checkpoints
On a concentrator or furnace
  • Controllers run in advisory mode, with each recommendation accepted or rejected explicitly
  • Performance tracked live against the baseline, visible to the shift and not only to management
  • Training on how the system reasons, not just which button to press
  • Alarm rationalisation, because an alarm nobody can respond to is worse than none
  • A site acceptance test against criteria agreed in advance
On a tailings facility
  • Detection runs in parallel with the existing inspection regime, never instead of it
  • Every alarm reviewed with the Engineer of Record before the system is given escalation authority
  • False-alarm rate measured in the field and thresholds tuned before TARP linkage is enabled
  • Instruments verified in situ against manual readings across a wet and a dry period
  • Reporting templates agreed with the people who will have to sign them
Phase 05
Deployment
Closed-loop activation happens on your operating team's decision, not ours, and only when they are confident, trained and ready to own it. The proven configuration is then extended across the rest of the asset, and ownership is transferred in full.
Skip the hand-over and you have bought a dependency, not a capability. A supplier that keeps the keys has an incentive you should not be paying for.
What we establish in this phase 10 checkpoints
On a concentrator or furnace
  • Closed loop activated on your team's call, with a documented reversion path
  • Scale-out from the template line to the rest of the circuit, then across the plant
  • Runbooks, model registry, retraining procedures and escalation path transferred
  • You own the models, the code and the right to change them
  • Support model agreed and staffed, with response times in writing
On a tailings facility
  • TARP linkage enabled, each escalation carrying an owner and a required response time
  • Instrumentation extended from the governing sections to full facility coverage
  • Governance reporting automated for the Engineer of Record, the RTFE and the Accountable Executive
  • A field maintenance schedule, because sensors that are not maintained become the risk they were installed to detect
  • Your team trained to add, replace and commission instruments themselves
Phase 06
Monitor the Value Generated
Value is measured against the countersigned baseline, normalised for grade and throughput, and reviewed on a fixed cadence using your finance numbers rather than ours. Every deployed model is monitored for drift, because a model that was right last year is not automatically right this year.
Skip it and the gain is claimed, never proven, and it quietly decays. Every model degrades as the operation changes around it. The only question is whether you find out from a monitoring plane or from a bad quarter.
What we establish in this phase 10 checkpoints
On a concentrator or furnace
  • Value measured against the baseline, normalised, and reviewed on a fixed cadence
  • Drift monitoring on inputs and predictions, with champion-challenger evaluation governing promotion
  • Scheduled retraining, plus a documented trigger for unscheduled retraining
  • Calibration and loop health re-audited on a defined interval. Phase 02 is not a one-off
  • Adoption reported alongside the metallurgy: acceptance rate, uptime, and which constraints bound
On a tailings facility
  • Water recovered, deposition efficiency and remaining storage life tracked against the baseline
  • Detection performance reviewed openly: what was caught, what was missed, what was noise
  • Instrument network health reported as a first-class metric alongside the facility itself
  • Annual reporting pack assembled automatically and reconciled against the independent review
  • Thresholds revisited after every raise, because the geometry the models were tuned on has changed
The Engagement Path

How the six phases
are packaged commercially.

The technical discipline is the six phases above. The commercial shape wrapped around it is fixed and public. It opens with a complimentary audit, formalises a countersigned baseline, proves the approach in a bounded pilot on one circuit, furnace or facility, and only then scales with ownership transferred to your team. Nothing is invoiced against a claim the baseline cannot test.

Complimentary Circuit Data Audit
A structured 90-minute session reviewing your data landscape and surfacing the single highest-value control or recovery opportunity. No cost, no commitment, full confidentiality.
No Cost
Diagnostic and Signed Baseline
On-site flowsheet and P&ID review with your team, closing on a countersigned Baseline Performance Certificate that fixes the reference period numerically.
2 to 4 Weeks
Pilot on a Template Line
A bounded deployment of soft sensing and hybrid control on one circuit or furnace, validated against the baseline before any wider rollout is contemplated.
Phased
Scale-Out and Continuous Optimisation
Proven gains extended across the plant, with the MLOps plane sustaining accuracy and full ownership transferred to your operating team.
Ongoing
// SELECTED MILESTONES
2026Ranked first in Africa in the EY AI and Data Challenge.
2025+3% absolute PGM recovery uplift delivered through data-driven flotation and regrind circuit stabilisation, measured against a signed baseline.
2025Multi-circuit hybrid APC and physics-informed soft sensor platform commissioned against signed performance baselines.
2024Hybrid Fuzzy Logic and Model Predictive Control deployed to stabilise particle size distribution and flotation under variable ore conditions.
15+ yrsHands-on metallurgical experience across PGM and chrome concentrators, milling, and smelting operations.
Capability Matrix

Nine practices,
one integrated framework.

Phase 03 draws on nine tightly coupled engineering practices. Each is governed by a single MLOps plane and a single accountability standard. The right tool for each loop and each facility, never an off-the-shelf product.

/CONTROL
Hybrid Advanced Process Control
A regulatory-layer stack that fuses Fuzzy Logic Control for constraint management and rapid disturbance rejection with Model Predictive Control for constraint-aware multivariable coordination across comminution, flotation, and milling. The hybrid APC holds the circuit feasible and steady on the setpoints handed down by the AI Optimisation Layer, never overcorrecting, never windup.
Hybrid FLC + MPCConstraint ManagementComminutionFlotation
/SENSING
Data-Driven Soft Sensors
Virtual instrumentation that infers unmeasurable process variables in real time where physical analysers are absent, unreliable, or cost-prohibitive. Physics-informed grey-box models predict grade, particle size, and chemistry every second, giving control the state awareness it has always lacked.
Grey-BoxInferential SensingFeature Engineering
/DATA
Real-Time Telemetry Pipelines
Scalable, edge-to-cloud data infrastructure that ingests high-velocity sensor streams without loss. Built on Azure Event Hubs, Apache Kafka, Databricks, and Snowflake, the medallion-architecture platforms consolidate historian, ERP, CMMS, and laboratory data into one governed environment.
Event HubsKafkaDatabricksSnowflake
/OPTIMISATION
AI Optimisation Layer
A supervisory machine-learning layer that sits above the Advanced Process Control stack, generating setpoint recommendations that are surfaced to operators and metallurgists for explicit accept or reject. Recommendation cadence is derived from the dominant time constant of the circuit it governs, and it is stated per circuit in the design. Thirty minutes is the comminution default. A leach or adsorption train whose residence time runs to hours is recomputed on a slower cadence, because an economic recommendation issued faster than the process can respond is noise, and an operator who is asked to judge noise stops reading the screen.
Supervisory LayerPer-Circuit Cadence2 Year TrainingOperator Approved
/RELIABILITY
Reliability Engineering
Probabilistic Remaining Useful Life forecasting across rotating and fixed equipment, TMM lifecycle tracking for haul fleets, vibration and oil-condition monitoring, and drone-based computer vision inspection for solar panels and wind turbines. Survival analysis, anomaly detection, and SHAP-explainable risk scores route engineering, procurement, and finance referrals before downtime is ever incurred.
Survival ModelsMask R-CNNTMM LifecycleRUL / CAPEX
/TWINS
Digital Twins and Virtual Commissioning
Physics-informed dynamic models of circuits and assets, synchronised continuously with live plant data. Test scenarios, tune setpoints, commission process changes virtually, and train operators against a faithful replica without ever placing the real plant at risk.
Process TwinsAsset TwinsWhat-If
/AGENTS
Agentic AI and RAG Knowledge Systems
Autonomous, fully auditable AI agents that plan, reason, and execute multi-step operational tasks, from incident triage to procurement triggers. Retrieval-augmented systems ground large language models in OEM manuals and SOPs, so any engineer can query decades of plant knowledge and receive cited answers in seconds.
Multi-AgentCopilotCited Retrieval
/REPORTING
Advanced Analytics and Reporting
Reporting ecosystems engineered for every stakeholder, from shift-level operator dashboards to board-ready KPI scorecards, all driven from a single governed source of truth. Pareto analysis, root-cause workbenches, and CAPEX waterfalls turn raw numbers into decisions.
KPI ScorecardsRCAParetoMobile PWA
/TAILINGS
Tailings Storage Facility Management
Real-Time GeotechWater BalanceTARP AutomationGISTM-Aligned
Instrumented, model-based management of the tailings stream from thickener underflow to deposition, beach, decant, and return water. Pore pressure, deformation, seepage, water balance and deposition are carried as live measured states rather than monthly inspection findings, with a purpose-built five-layer anomaly detection stack and reporting aligned to the Global Industry Standard on Tailings Management. Every engineering decision stays with the Engineer of Record. What the platform changes is that the evidence becomes continuous, traceable and reproducible.
Start the conversation

A 90-minute review can locate the single highest-value loop in your circuit.

Complimentary, no commitment. We review the data landscape, walk the historian against the control narrative, and surface the most economically significant intervention available in the next 60 days.

Axiom Capability

Mineral Processing Optimisation

Crushing Milling Flotation Leaching Adsorption Dewatering Water Reticulation

Crushing, milling, flotation, leaching, adsorption, dewatering, and the water that returns. The full circuit, the whole circuit, controlled.

Mineral processing rewards the operation that controls variance, not the one that chases the mean. Recovery is a non-linear function of feed grade, mineralogy, particle size, pulp density, reagent suite, gas holdup, and froth phase behaviour, and these variables are coupled across the comminution, flotation, and water reticulation circuits. Axiom engages the full sequence as the single coupled system it physically is, never as a collection of unit operations to be tuned in isolation.

Mineral Processing Challenges

Mineral processing operations face a wide spectrum of structural challenges that erode throughput, recovery, and stability. The set below names the most common ones we engage on a typical concentrator, not the full taxonomy. Each is invisible to conventional control, and each yields to an Axiom engineered interface: a soft sensor that turns the unobserved into a continuously controllable signal.

Ore Hardness Transitions Disrupt Throughput
Hardness shifts arrive at the mill hours before laboratory assays catch them. The plant sees the consequence as lost throughput and unstable recovery long before anyone can name the cause. The latency between hardness change and operator response is the single largest source of avoidable variability in comminution.
Axiom Engineered Interface Continuous ore hardness soft sensor built on existing SCADA. Feeds forward to the APC layer so mill speed, water addition, and feed rate are adjusted in anticipation, not reaction. Architecture in Paper P-001.
Liner Wear Drives Silent Energy Creep
Lifter profile and liner thickness shift the charge trajectory through a campaign. Specific energy drifts upward against a steady tonnage, paid for and unrecorded. Most plants reline on the calendar, not on the wear curve.
Axiom Engineered Interface Liner Wear Index soft sensor fuses mill power signature, charge filling, and cumulative throughput into a wear state per liner segment. Reline planning shifts from calendar-driven to condition-driven.
Cyclone Overflow PSD Drifts Off Target
The particle size distribution leaving the cyclone is the single most consequential output of the comminution circuit. Coarse particles starve flotation kinetics; fines depress grade. The laboratory PSA loop arrives half a shift after the move that needed correcting.
Axiom Engineered Interface Online PSD soft sensor combining image-based classification with a cyclone hydrodynamic model. The overflow PSD becomes a real-time controlled variable, reconciled against periodic laboratory PSA. Where the duty justifies direct measurement, we specify per-cyclone instrumentation rather than build an inferior equivalent: clamp-on overflow particle size sensing, and acoustic roping and wear detection on individual cyclones.
Recovery Plateaus Below Its Achievable Frontier
Stable does not mean optimal. A plant can sit within standard deviation of its targets for months while running structurally below what the ore can deliver. Without a continuous estimate of concentrate grade and recovery, the operator has no faster signal than the next assay.
Axiom Engineered Interface Pay-metal grade soft sensor and continuous grade-recovery surface estimator. The AI Optimisation Layer recomputes the economic operating point on a cadence derived from the circuit's dominant time constant; the operator accepts or rejects before any setpoint is committed.
Reagents Tuned to Yesterday's Ore
Collector and depressant dosing tuned to last quarter's mineralogy is the wrong dose for this morning's feed. As ore drifts, selectivity moves with it, and a constant dosage turns from optimal to over-reagented to under-reagented inside a single shift.
Axiom Engineered Interface Reagent Selectivity Index estimator combines reagent intensity, feed characterisation, and ensemble grade prediction. Iron-ore template in Paper P-002; generalises to PGM, copper, and base-metal sulphide circuits.
Mass Pull and Froth Phase Out of View
Mass pull and froth velocity are where flotation circuit performance lives or dies. Conventional control reads them retrospectively from concentrate flow. Below-lip cell losses accumulate silently as ore that should have floated reports to tailings.
Axiom Engineered Interface Froth-phase soft sensor combining mass-pull predictor and froth-velocity estimator from camera analytics. The APC layer holds froth pull and mass pull on target across the bank.

The Axiom control hierarchy, five layers, one contract.

A control stack delivers value only when each layer does its own job, and only its own job. The Axiom architecture is five layers, from the DCS upward. Each layer operates at the timescale its physics demands, and hands a well-defined signal to the layer above.

L5
Supervisory · Economic

AI Optimisation Layer

Recommends economic setpoints for the whole circuit. Every recommendation is surfaced to operators for explicit accept or reject before it is handed down. The layer carries the operation's regulatory and safety limits as hard constraints alongside the process and equipment constraints. Discharge quality, emissions, occupational exposure, water licence conditions and permit boundaries define the edge of the feasible region. They are not terms weighed against economics.

An economic optimiser without them will eventually find value on the wrong side of a limit, and it will find it faster than a human would. This is not a compliance disclaimer. It is a statement about what an unconstrained objective function does when it is allowed to run.

L4
Advanced Process Control

APC Layer

Coordinates multivariable moves against process constraints and disturbances, holding the plant on target through the noise that regulatory control alone cannot handle.

L3
Continuous Estimation

Physics-Informed Soft Sensors

Estimates the variables the plant cannot measure directly. First-principles physics with machine-learning corrections, calibrated against laboratory reality.

L2
Integrity Watchdog

Anomaly Detection Layer

Watches the plant's healthy operating envelope and flags any departure. Overrides are not failures, they are training signal for the next revision.

L1
Regulatory Foundation

Healthy DCS

Stable, well-tuned regulatory control on the plant's installed PLC and DCS. No layer above is engaged until the foundation passes a formal Control Readiness check.

Layer 2 / The Contract

What happens when a measurement fails

Every signal carries a health state, and the controller's response to each state is defined in writing before commissioning rather than decided during an incident.

Signal state
What the controller does
What the operator is told
Good
Full operation
Nothing
Suspect
Widens its constraint margins in proportion to the uncertainty
Which estimate lost confidence, and that the controller is being more conservative as a result
Bad
Drops that input, widens margins further, continues on the remaining measurements
Which measurement failed, and which capability was lost with it
Multiple bad, or model residual outside its band
Returns control to the regulatory layer at the last known good setpoint
Why it stood down, and what has to be restored before it will resume
The controller never silently keeps controlling on a dead sensor. In our experience this contract does more to earn control-room trust than any amount of performance, because it is the honest answer to the question every operator is entitled to ask: what happens when your model is wrong?
Layer 3 / The Standard

Before an estimate is allowed to move a setpoint

Every soft sensor clears a published floor: an R² of at least 0.85 on held-out future periods, with RMSE and MAE both reported. Three further conditions apply, and all three exist because the floor on its own can be cleared by a model that is quietly unfit for control.

Performance is reported stratified, not pooled
A model can clear the floor overall and fail completely on one feed type or one operating mode. We publish performance broken out by mode and by feed classification, because the pooled figure conceals precisely the conditions in which the controller most needs the estimate to hold.
Uncertainty is calibrated, not nominal
The control layer widens its constraint margins in proportion to the estimator's stated uncertainty, so an uncalibrated uncertainty makes that margin arbitrary. We demonstrate prediction-interval coverage on held-out data before the estimate is allowed near a setpoint.
The estimator declares when it is extrapolating
Every soft sensor carries a validity-domain check and reports when current conditions sit outside the envelope it was trained on, rather than returning a confident number from outside its own experience.
The circuit does not end here
Comminution decides what can be recovered. Hydrometallurgy decides what is. The dewatering stage sits between them and sets the terms for both, because the density it delivers fixes the volumetric load, the residence time and the reagent concentration in everything downstream. We engage all three as one system, and we have separated them here only so each is findable by the people who run it.
Signed by
Terrence Davhana, Technical Director. Owns engagement scoping through to the models and control strategies that run in the control room, across milling, flotation and furnace circuits. Deliverables on this practice that carry an engineering judgement are signed by a named engineer.
Engagement-Scoped
Loop-by-loop scoping for each stage is sized and committed against a signed performance baseline during the Circuit Data Audit. The architecture is public; the per-circuit configuration is engagement.
Further reading
The soft-sensing architecture described above is set out in detail in two technical papers: P-001, A Physics-Informed Soft Sensor for Real-Time Ore Hardness Estimation in SAG Mills, and P-002, An Ensemble Soft Sensor for SiO2 Grade Prediction in Iron Ore Reverse Cationic Flotation. Both are available under Technical Documents. What we hold ourselves to on every estimator is published under What We Publish.
Start the conversation

A 90-minute Circuit Data Audit can locate the single highest-value loop in your circuit.

Complimentary, no commitment. We review the data landscape, walk the historian against the control narrative, and surface the most economically significant intervention available in the next 60 days.

Axiom Capability

Hydrometallurgy

Leaching Adsorption Reagent Control Residence Time Loss Decomposition

The circuit where time is the reagent you cannot buy more of.

Circuits this applies to
Gold and silverCyanidation with carbon adsorption, CIL and CIP, elution and regeneration.
CopperAcid and alkaline leaching of oxides, heap and agitated, with solvent extraction downstream.
UraniumAcid and alkaline leaching with resin or solvent recovery.
Nickel and cobaltAtmospheric and pressure circuits, including laterite feed.
The chemistry differs by commodity. The control discipline does not. Every structural challenge below appears in all four, because all four are governed by the same three variables: what is in the feed, what is in solution, and how long the reaction has.

Comminution decides what can be recovered. Hydrometallurgy decides what is. The two are separated by a dewatering stage and joined by a constraint most circuits never write down: the time available for the reaction to finish.

Throughput, delivered density and installed tank volume together set residence time, and of the three only tank volume is fixed. Yet residence time is almost never carried as a measured state, which means an operation can lose a third of it to a dewatering setpoint that drifted, and find out from a residue assay two shifts later.

The architecture below applies to cyanidation and carbon adsorption, to acid and alkaline leaching of copper oxides, to uranium leaching with resin or solvent recovery, and to atmospheric and pressure circuits on nickel and cobalt. The chemistry differs by commodity. The control discipline does not.

Hydrometallurgy Challenges

Leaching and adsorption circuits fail quietly. There is no froth to watch, no power draw that spikes, no obvious signature when a circuit begins running below what the ore could give it, only an assay that arrives after the conditions have already changed. The set below names the most common structural challenges we engage, not the full taxonomy. Each is invisible to conventional control, and each yields to an Axiom engineered interface: an estimator that turns an unobserved state into a continuously controllable signal.

Reagent Dosing Tracks Tonnes, Not Demand
Dosing is almost universally set as a ratio to throughput. Chemical demand, however, is set by mineralogy: gangue acid consumption, reactive sulphides, clays, carbonaceous constituents and oxidised surfaces all move with the feed while the ratio stays where it was last tuned. A constant kilogram per tonne is correct for the average ore and wrong for every actual ore, and the error alternates between overdose and underdose within a single shift.
Axiom Engineered Interface Reagent demand soft sensor, driven by feed classification, mineralogical proxies and the upstream comminution state. The dosing setpoint moves with the ore rather than with the belt scale, feeding forward so the correction arrives with the material instead of after it. Reagent consumption becomes a predicted and budgeted quantity rather than a month-end reconciliation.
Residence Time Is Set Two Units Upstream
The volumetric load on a leach train is set by the dewatering density that precedes it, not by anything inside the leach circuit. A thickener or filter delivering below its density setpoint sends the same solids in more water, and residence time falls in proportion. It falls silently, because no instrument in the leach circuit measures it. Kinetics that were adequate at design density are not adequate at delivered density, and the shortfall is paid in dissolved metal that never had time to dissolve.
Axiom Engineered Interface Residence time carried as a live measured state, computed continuously from solids rate, delivered density and live volume. Dewatering density is promoted from fixed plumbing to a manipulated variable of the downstream circuit, and a minimum residence time becomes a hard constraint on upstream throughput. Where an operation is recovery-limited rather than tonnage-limited, this single constraint changes what the optimisation layer is allowed to do with additional tonnes.
Solution Chemistry Decays Along the Train
Alkalinity, reagent concentration and oxidation potential are controlled at the head of the train and then consumed, stage by stage, by the reaction they exist to drive. Controlling at the head while measuring only at the head guarantees that the tail of the train operates in conditions nobody has specified. The last stages, where the final increment of recovery is won and where a reagent excursion is most consequential, are typically the least instrumented in the circuit.
Axiom Engineered Interface Stage-by-stage chemistry profile as a controlled state. Reagent, alkalinity and oxidant addition distributed along the train against the measured profile rather than concentrated at the front, so the specified condition is held where the reaction still has work left to do. The profile itself becomes a diagnostic: its shape identifies which stage is consuming what, and therefore which unit owns the loss.
The Oxidant Is the Hidden Co-Limit
Most leach reactions are co-limited by an oxidant as well as by the reagent. The reagent is expensive and closely controlled. The oxidant is cheap, assumed abundant, and frequently unmeasured anywhere in the circuit. Where the ore itself consumes oxidant, and reactive sulphides are the common case, a circuit can be oxidant-starved while the reagent sits exactly on setpoint, and every diagnosis built on reagent concentration alone will point in the wrong direction.
Axiom Engineered Interface Oxidant demand estimator with dissolved-oxidant control. Demand predicted from feed characterisation, supply controlled against direct measurement, and the reagent-to-oxidant ratio held against the reaction stoichiometry so that neither is optimised in isolation. Where oxidant generation capacity already exists on site, it is scheduled against measured demand rather than run as a fixed utility or left idle.
Adsorption Runs on a Schedule, Not on a State
Adsorbent advance, elution and regeneration are usually scheduled by routine. The states that actually determine whether dissolved metal is recovered or discharged are the loading profile down the train, the inventory held in each stage, and the activity of the adsorbent itself, and all three move continuously while the schedule does not. Dissolved metal leaving in solution never appears in a solids assay, which is why it is the least diagnosed loss in hydrometallurgy.
Axiom Engineered Interface Adsorbent inventory and loading profile as live states. Advance rate, stage inventory and regeneration scheduled against measured loading and activity rather than against the calendar. Soluble loss is reported as a number in its own right, separately from solid residue, so that two failure modes with two different owners are never averaged into one.
Losses Are Diagnosed After the Fact
The residue assay arrives long after the conditions that produced it, and it arrives as a single number that conflates four different failures belonging to four different parts of the operation: metal never liberated, metal liberated but not dissolved, metal dissolved but not recovered, and metal lost mechanically. An aggregate residue number tells an operation that it has a problem. It does not tell anyone whose problem it is, which is why residue meetings tend to end where they began.
Axiom Engineered Interface Standing loss decomposition. Residue attributed continuously across liberation, dissolution, recovery and mechanical loss, each routed to the unit operation that can act on it. Comminution owns liberation, leach chemistry owns dissolution, the adsorption circuit owns recovery. A decomposition that changes shape is itself the alarm, and it arrives before the monthly number does.
Coarse Values Outrun the Kinetics
Dissolution rate falls sharply with particle size. A coarse value particle can be fully liberated, sitting in perfect chemistry, and still be undissolved when the slurry reaches discharge, simply because the time available is shorter than the time that particle needs. Standard assay methods on a small charge under-report this population by their nature, so a circuit can lose coarse values persistently while the assay quietly agrees that everything is fine.
Axiom Engineered Interface Size-resolved loss tracking, and a recovery-versus-grind relationship that is measured rather than assumed. Where coarse values are present, the optimisation layer trades grind size against dissolution kinetics and against any size-selective recovery installed ahead of leach, rather than treating grind as a comminution decision made in isolation from the circuit that has to dissolve the result.
Discharge Chemistry Is a Licence Condition
Reagent that reports to the tailings stream is three things at once: a reagent cost, a load on the destruction circuit, and a permit exposure. It is typically managed by three different people who do not share a number, and it is optimised by none of them. A circuit can be simultaneously over-consuming reagent and approaching a discharge limit, and see neither, because nobody owns the stream that carries both.
Axiom Engineered Interface Discharge chemistry as a controlled variable with a hard limit. Destruction circuit duty scheduled against measured load rather than run as a fixed utility, and the discharge limit itself carried as a boundary of the feasible region inside the optimisation layer, never as a term weighed against economics.
If throughput rises and residence time does not, the circuit has not gained anything. It has only moved the loss downstream.
/ A first principle of hydrometallurgy
Residence time is set two units upstream
The single largest lever on this circuit is not inside it. Delivered density fixes the volumetric load, which fixes residence time, which fixes how much of the dissolvable metal actually dissolves. That decision is made at the thickener, and it is made by people who are not measured on recovery.
Signed by
Terrence Davhana, Technical Director. Physics-informed soft sensors and hybrid control across metallurgical circuits, from engagement scoping to what runs in the control room. Deliverables on this practice that carry an engineering judgement are signed by a named engineer.
Engagement-Scoped
The estimator set for a leach or adsorption train is scoped against your circuit and committed against a signed performance baseline. The architecture is public; the configuration is engagement.
Start the conversation

A 90-minute Circuit Data Audit can establish what your leach data can actually support.

Complimentary, no commitment. We walk the assay cadence, the residence time assumptions and the accounting against the decisions each one is currently being used to make, and you leave with a documented short-list.

Axiom Capability

Dewatering and Water

Thickening Filtration Slurry Transport Water Reticulation Mass Balance

The most consequential number on the plant is the one nobody owns.

Dewatering sits between the concentrator, the hydrometallurgical circuit and the tailings facility, and it sets the terms for all three. The density it delivers fixes residence time in the leach, water returned to the plant, and the dry tonnage that becomes rate of rise on the wall. It is usually managed as plumbing, by people measured on none of those things.

The argument this page exists to make

A calibration drift on a density gauge is a geotechnical error, not an accounting error.

Slurry density and solids fraction are related by a mixing rule that is not in dispute:

ρslurry = ρwater + Cv(ρsolids − ρwater)

Rearrange for the volumetric solids fraction and differentiate, and a relative error in measured slurry density does not pass through to solids fraction one for one. It is amplified, by a factor of ρslurry / (ρslurry − ρwater). The amplification is worst exactly where most tailings streams run, because the denominator is the part of the density that the solids contribute, and at low density there is very little of it.

So a density gauge reading half a percent high at a specific gravity of 1.50 does not put your solids concentration out by half a percent. It puts it out by roughly one and a half percent, and dry tonnage with it.

Dry tonnage sets rate of rise. Rate of rise governs whether pore pressure can dissipate as fast as load is applied. That is the mechanism, and it means an instrument technician's calibration interval is quietly a geotechnical control. Nobody on the plant sees that chain, because it crosses three departments and two disciplines.

Error amplification, solids fraction against slurry density
Slurry SG
Amplification
0.5% gauge error becomes
1.30
4.3×
2.2% on solids
1.50
3.0×
1.5% on solids
Computed from the mixing rule above at a water density of 1.00. The amplification depends only on the slurry density, not on the solids specific gravity, which is why it holds across commodities.
Density gauge drift Solids concentration error, amplified Dry tonnage error Rate of rise error Pore pressure cannot dissipate as fast as load is applied

What has to be true before a controller is built on a slurry stream

Every item below is checked and written down before any model is trained. None of it is exotic. All of it is routinely assumed rather than verified, and each one fails in a direction that flatters the number rather than exposing it.

Density
Calibrated against a physical sample, not against itself
A nuclear density gauge is calibrated against a dry-and-weigh sample taken from the same stream, not against its own historian trend. We also check whether the solids specific gravity in the calculation is current, because it is entered once at commissioning and the orebody moves.
Entrained air
Fails in the direction that hides the problem
Air in the stream makes a nuclear gauge read low. A circuit carrying air therefore under-reports solids, under-reports dry tonnage and under-reports rate of rise. The error flatters every number it touches, which is why it survives.
Flow
Full pipe, straight lengths, intact liner
A magnetic flowmeter needs a full pipe and its specified upstream and downstream straight lengths to mean anything. Liner and electrode wear are checked, because a worn electrode degrades quietly rather than failing.
Pipe geometry
Internal diameter drifts, velocity does not know
Wear opens the bore. Every velocity derived from a volumetric flow and a nominal diameter is then wrong, and it stays wrong in a slowly worsening direction. We measure the bore rather than reading it off the line list.
Pressure gradient
The only continuous read on the line
Pressure along the route is the one measurement that sees packing, settling and leaks continuously. Where it does not exist we say so, because without it the first indication of a settling line is usually the line.
Historian
Scan rate, compression and deadband
The resolution detection needs is destroyed silently at the historian, not at the instrument. A deadband set for storage efficiency removes exactly the small movements a drift detector exists to find. We audit this before we trust a single trend.
The settling test
If the solids balance will not close, no controller should be built on those instruments, and we will say so.

There is one test that settles whether the instrumentation on a slurry stream can carry a model. Integrate flow times density times solids specific gravity over a period, and compare it against surveyed deposited volume times measured in-situ dry density over the same period. Two independent measurement chains, one physical quantity. They either agree to a defensible tolerance or they do not.

If they do not, one of them is wrong, and every economic claim, every soft sensor and every rate-of-rise number downstream inherits the error without any indication that something is missing. We do not proceed to build on an open balance. We report the residual, we bound it, and we scope the remediation that closes it. That is frequently a smaller and less interesting piece of work than the one we were asked for, and we say so anyway.

Water Reticulation

The circuit runs on water it can never fully get back.

Mineral processing is water-intensive, and much of the water fed to the plant leaves locked in the tailings rather than in the concentrate. No operation recovers all of it: water is lost to entrainment in the tailings, to evaporation, and to seepage, so every concentrator runs on continuous makeup water. Where water is scarce, that makeup supply, not the mill, is the real limit on throughput.

Dewatering and reticulation are usually treated as fixed plumbing, yet thickener density, filtration, and reclaim are all manipulated variables that move recovery, reagents, and energy at once. The aim is straightforward: water can only be managed once it can be seen. Axiom instruments the full network as a live mass balance, every stream metered and reconciled, so the APC layer can hold water usage as a controlled objective and return makeup water to throughput.

Treated as a controlled objective rather than a consequence, dewatering density stops being a thickener setting and becomes what it physically is: a manipulated variable of the circuit two units downstream, constrained by the thickener's own limits but optimised against the recovery and the rate of rise it actually governs.

If it cannot be measured, it cannot be controlled. If it cannot be controlled, it cannot be optimised.
A first principle of process control
This page is the join
Everything on it is consumed by something else. The density sets the kinetics in one direction and the rate of rise in the other, which is why we will not scope a thickener in isolation from the two circuits it governs.
Signed by
Terrence Davhana, Technical Director. Owns the instrument fitness register and the balance closure work on this practice, including the decision to report an open balance rather than build a controller on top of one. Deliverables on this practice that carry an engineering judgement are signed by a named engineer.
Engagement-Scoped
The instrument fitness register and the solids balance closure attempt are the substance of the Facility Evidence Baseline, a four to six week piece of work with its scope written down before it starts.
Start the conversation

A 90-minute review can establish whether your solids balance closes.

Complimentary, no commitment. A Tailings Evidence Review if the question is the facility, a Circuit Data Audit if the question is the plant. Either way it ends with a documented short-list of where the measurement chain is thin, and neither creates an obligation.

Axiom Capability

Pyrometallurgy Optimisation

Kilns SAFs Electrode Columns Refractories Slag Chemistry

Kilns, furnaces, electrode columns, refractories. The slow physics that no PLC was ever designed to manage.

A pyrometallurgical operation is a coupled electrical reactor, thermo-chemical reduction vessel, and structural refractory system, fed by an upstream pelletising or sintering circuit that determines whether the furnace ever stood a chance. The architecture below applies equally to ferrochrome submerged-arc furnaces, copper flash and reverberatory smelters, nickel and PGM smelters, and the rotary kilns and pelletisers that feed them. Operations differ in chemistry, the control discipline does not.

Pyrometallurgy Challenges

Pyrometallurgical operations carry a wide spectrum of challenges spanning electrical, thermal, refractory, and chemistry domains. The set below names the most common ones we engage across submerged-arc furnaces, electric arc furnaces, flash and reverberatory copper smelters, and the kilns and sinter strands that feed them. The list is representative, not exhaustive. Each yields to an Axiom engineered interface: a soft sensor that turns the unobservable into a continuously controllable signal.

Specific Energy Drift Eats Margin
Electricity is around forty percent of smelter operating cost in most Southern African operations. Every kWh per ton above design SEC is paid out of margin. Most plants do not measure SEC with the loop-by-loop granularity needed to defend it.
Axiom Engineered Interface Loop-by-loop SEC tracker decomposes total kWh per ton into furnace duty, auxiliaries, and tap-house losses. The APC layer holds furnace SEC inside a defensible band against tariff structure.
Furnace State Hidden at Temperature
Electrode tip position, slag-metal interface depth, slag chemistry, and hearth wear are inaccessible to direct measurement at temperature. Control systems that ignore the state estimate eventually drop an electrode, run a paste blow, or burn through a side wall.
Axiom Engineered Interface Coupled electrode tip position estimator and hearth wear soft sensor, updated per minute from electrical signatures and skin-temperature arrays.
Soderberg Bake Drift Ends Campaigns
The paste baking curve is silent for days and catastrophic for years. Slip schedules tuned by historical rhythm rather than online state estimation put the electrode column at risk every shift the burden or current density changes.
Axiom Engineered Interface Baking-front position estimator combines current, voltage harmonics, slip history, and paste consumption rate. Slip schedule cast as a constrained scheduling problem; paste-blow risk reported per shift.
Substandard Pellets Burn Furnace Time
Cold, sandy, or out-of-spec pellets arrive at the furnace and waste electricity on duty the kiln was supposed to do. Pellets that disintegrate displace useful burden and pull slag chemistry off target. The energy cost is paid at the most expensive point in the flowsheet.
Axiom Engineered Interface Pellet quality soft sensor at kiln discharge predicts metallisation, residual carbon, and size fraction every minute. Kiln APC trims throughput and air-to-fuel ratio against quality acceptance.
Refractory Wear Inspected Too Late
Refractory wear is conventionally inspected at tap and characterised after the campaign ends. The difference between a planned reline and a forced outage is a hot-spot forecast measured in hours, not retrospective dissection.
Axiom Engineered Interface Refractory wear soft sensor fuses skin-temperature arrays, cooling water differential, and freeze-line position into a continuously updated wear-profile map. Reline campaigns aligned with production planning.
Slag Chemistry Lags the Burden
Feed and reductant blend, slag basicity, and metal silicon are coupled through reactions that respond on the order of hours. Operating decisions are made on the order of minutes. Power-only control drifts off chemistry; the operator finds out at the next tap analysis, twelve or twenty-four hours later.
Axiom Engineered Interface Slag chemistry soft sensor fuses off-gas composition, electrical signature, burden balance, and periodic XRF tap analysis. The APC layer trims reductant and feed blend before chemistry departs band.

The same five-layer hierarchy, applied to the furnace

The control hierarchy that governs the concentrator governs the smelter. The layers, the cadences, and the contracts between them are identical. The variables, the constraints, and the consequences of failure are not.

L5
Supervisory · Economic

AI Optimisation Layer

Recommends economic setpoints for the whole circuit. Every recommendation is surfaced to operators for explicit accept or reject before it is handed down. The layer carries the operation's regulatory and safety limits as hard constraints alongside the process and equipment constraints. Discharge quality, emissions, occupational exposure, water licence conditions and permit boundaries define the edge of the feasible region. They are not terms weighed against economics.

An economic optimiser without them will eventually find value on the wrong side of a limit, and it will find it faster than a human would. This is not a compliance disclaimer. It is a statement about what an unconstrained objective function does when it is allowed to run.

L4
Advanced Process Control

APC Layer

Coordinates multivariable moves against process constraints and disturbances, holding the plant on target through the noise that regulatory control alone cannot handle.

L3
Continuous Estimation

Physics-Informed Soft Sensors

Estimates the variables the plant cannot measure directly. First-principles physics with machine-learning corrections, calibrated against laboratory reality.

L2
Integrity Watchdog

Anomaly Detection Layer

Watches the plant's healthy operating envelope and flags any departure. Overrides are not failures, they are training signal for the next revision.

L1
Regulatory Foundation

Healthy DCS

Stable, well-tuned regulatory control on the plant's installed PLC and DCS. No layer above is engaged until the foundation passes a formal Control Readiness check.

Layer 2 / The Contract

What happens when a measurement fails

Every signal carries a health state, and the controller's response to each state is defined in writing before commissioning rather than decided during an incident.

Signal state
What the controller does
What the operator is told
Good
Full operation
Nothing
Suspect
Widens its constraint margins in proportion to the uncertainty
Which estimate lost confidence, and that the controller is being more conservative as a result
Bad
Drops that input, widens margins further, continues on the remaining measurements
Which measurement failed, and which capability was lost with it
Multiple bad, or model residual outside its band
Returns control to the regulatory layer at the last known good setpoint
Why it stood down, and what has to be restored before it will resume
The controller never silently keeps controlling on a dead sensor. In our experience this contract does more to earn control-room trust than any amount of performance, because it is the honest answer to the question every operator is entitled to ask: what happens when your model is wrong?
Engagement-Scoped
Loop-by-loop scoping for each furnace, kiln, and electrode column is sized and committed against a signed performance baseline during the Complimentary Circuit Data Audit. The architecture is public; the per-smelter configuration is engagement.
The DCS Gate
The Axiom engagement does not commission APC on a smelter until the Distributed Control System and its installed regulatory loops pass a formal Control Readiness check, with a countersigned certificate. No certificate, no APC. Every layer above the DCS is structurally dependent on it; pretending otherwise puts the campaign at risk. The Control Readiness phase is the precondition for everything that follows, and it is included in every engagement scope as a non-negotiable gate.
Signed by
Helly Nkhuna, Director, Pyrometallurgy. Nineteen years across flotation, smelting and plant operations, including process metallurgy on the smelter and final product plant at Rio Tinto Richards Bay Minerals, covering furnace operation, electrode consumption, slag chemistry and freeze lining integrity. He owns this practice. Deliverables on this practice that carry an engineering judgement are signed by a named engineer.
Start the conversation

A 90-minute Circuit Data Audit can locate the single highest-value constraint on the furnace.

Complimentary, no commitment. We review the furnace data landscape, walk the historian against the operating narrative, and surface the most economically significant intervention available in the next 60 days.

Axiom Capability

Tailings Storage Facility Management

Real-Time Instrumentation Anomaly Detection Water Balance Deposition Control GISTM-Aligned Reporting

Your slimes dam is built every hour of every shift. Measure it that way.

A tailings facility is designed by geotechnical engineers and then built, continuously, by a thickener, a pump and a pipeline. Axiom instruments that whole chain and turns pore pressure, movement, seepage and water balance into live measured states instead of monthly readings. Your Engineer of Record keeps every engineering decision. What changes is that the evidence never stops.

Vibrating-wire piezometersIn-place inclinometerGNSS crest nodeToe drain weirSeepage thermal scanDecant radar levelBeach profile, drone LiDARDelivery line and spigotsWeather and rainfallAutomated total stationWall cameraSatellite InSARSOLAR EDGE GATEWAYENCRYPTED, OUTBOUND ONLYAXIOM TSF PLATFORMPHREATIC SURFACE VS DESIGNLIVE DASHBOARDTARP ALERT AND OWNERGOVERNANCE REPORTING
Every point on the wall is a decision waiting for data 12 sensing classes  /  1 gateway  /  1 governed record Illustrative deployment, sized per facility
Vibrating-wire piezometers, nested at design-critical elevations In-place inclinometers and continuous shape arrays in the wall Continuous GNSS nodes on the crest and berms Toe drain weirs with flow, turbidity and conductivity Thermal scanning for seepage expression on the wall face Radar level on the decant pond, referenced to freeboard Beach profile and volume from drone LiDAR Delivery line, spigot and cyclone instrumentation Weather station: rainfall, evaporation, barometric reference Automated total station with prism arrays Fixed cameras with vision analytics on the wall Satellite InSAR for wide-area displacement

Most tailings monitoring tells you whether the sensor is talking

The harder question, and the one an alarm you can trust depends on, is whether it is telling the truth. Network liveness and device health answer the first. Nothing answers the second, because knowing that an instrument has failed and knowing that a structure is moving are different problems needing different methods, and a system that treats them as one produces alarms nobody acts on. Layers one to four establish that the data is real. Layer five, which generic anomaly detection does not contain, asks what real data says about the physical state of the facility.

L1
Signal health, per tag, every reading
Catches the dangerous failure: a sensor that stops measuring but keeps reporting. A perfectly quiet transmitter is usually dead, not stable. A displacement event that is really a lost GNSS fix must never reach a TARP.
Stuck-atNoise-floor collapseVW coil diagnosticsGNSS fix quality
L2
Multivariate monitoring, per deposition mode
The instrument network watched as one system, with separate models per deposition point, rate of rise and season. Every alarm names its cause. An alarm that says something is wrong is noise. An alarm that says, for example, that most of the excursion is attributable to the upstream shell piezometer cluster on one named section gets acted on.
PCA T² and QContribution plotsMode-specific models
L3
Analytical redundancy against physical balances
The only reliable way to catch a slowly drifting instrument is consistency against physics, not statistics on the instrument itself. A drifting density gauge shows up as a growing solids balance residual weeks before it ever trips an alarm. Five balances are closed and trended continuously.
Water balanceSolids balanceRate of rise vs tonnagePhreatic consistencyFreeboardCUSUM and EWMA
L4
Unsupervised detection for states never seen
A design storm on a high pond, a plant trip that lets the line pack, the first wet season after a raise. Used as an advisory flag that raises engineering attention, never as an automatic escalation. An escalation process that cries wolf is worse than none.
Isolation ForestAutoencoder residualAdvisory only
L5
Geotechnical state, the physics statistics cannot replace
Phreatic surface reconstructed daily and differenced against the design surface. Excess pore pressure against loading. Rate of rise against the consolidation the material can actually accommodate. Inverse velocity on every displacement series. A movement pattern that is not kinematically plausible is an instrument problem, not a slope problem, and saying so quickly is what protects trust in the whole system.
Phreatic vs designExcess pore pressureInverse velocityState parameter
The argument this whole page rests on

A facility measured once a month is unobserved for the other twenty-nine days.

A monthly piezometer reading gives you twelve numbers a year. Hourly telemetry gives you 8,760, and with them a response function rather than a single value. You stop asking what the head is and start asking how it responds to rainfall, to rate of rise, to a change in underflow density. A response that changes is a warning. A response that disappears is either a drifting instrument or a clogging tip.

None of those questions exist at monthly resolution. This is an argument about resolution, not about technology, and it is the honest reason to instrument a facility. Every decision taken between two readings rests on an assumption.

1 : 730
Monthly against hourly reading density
Monthly manual12 readings a year
Hourly telemetry8,760 readings a year
24 × 365. The ratio is arithmetic, not a claim.

Two facilities where the interval was the problem

Both are public record and both are stated as reported. Neither is offered as a sales argument. They are here because each one turned on evidence that existed but was not continuous, which is the specific failure the resolution argument above describes.

270
Brumadinho, Brazil, January 2019
The dam was subject to a routine field inspection regime, and it was reported afterwards that the operator had been aware of problems with the instruments meant to monitor its structural integrity. An inspection interval cannot see what a failed sensor is hiding.
Lives lost / publicly reported
Warnedand not acted on
Jagersfontein, South Africa, September 2022
Concerns about this facility were on record for years before it failed, and the collapse has since been reported as foreseeable and preventable. Lives were lost, more than forty people were taken to hospital and homes were swept away. The warnings existed. The continuous, traceable evidence that would have forced action on them did not.
As publicly reported and investigated

How it works

Six steps, running continuously, from the sensor on the wall to the report on the executive's desk.

01
Sense
Instruments on the wall, the beach, the pond and the delivery line, plus drone and satellite survey.
02
Connect
Solar LoRaWAN gateways with cellular and satellite fallback. A backhaul outage delays data, it never loses it.
03
Detect
Five detection layers run on every reading, separating a failing instrument from a changing structure.
04
Attribute
Every alarm arrives with the cause it is attributable to, the raw evidence, and a named owner.
05
Act
Detections map straight onto your Trigger Action Response Plan, with a required response time.
06
Report
Governance packs for the Engineer of Record and the Accountable Executive, built from the same data.
The Differentiator

Most monitoring starts at the wall. Ours starts at the thickener underflow.

Thickener
Underflow density
Pump and Line
Velocity, wear, leaks
Deposition
Spigots and cyclones
Beach and Wall
Slope, pore pressure
Decant
Freeboard and return

What we install

No facility gets all of it. The plan is sized against your risk assessment and the failure modes your Engineer of Record has identified, and every item is justified in writing against a decision it will inform. We name the requirement, never the supplier. We make no instrument and hold no distribution agreement, so the specification below cannot be written toward a product we would be paid for. The choice of manufacturer is yours, and it is normally made against your existing site standards and support arrangements.

Pore pressure
The governing measurement
Nested vibrating-wire piezometers on wireless nodes, with standpipes retained deliberately as an independent check. Two principles disagreeing is information. One principle agreeing with itself is not.
Movement
Surface and subsurface
Continuous shape arrays and in-place inclinometers in boreholes, continuous GNSS on the crest, automated total stations with prisms, and MEMS tiltmeters on critical structures.
Seepage
Character before volume
Instrumented weirs and flumes on every drain, with turbidity and conductivity. Internal erosion shows in the particles long before it shows in the flow rate. Fibre optic sensing where risk justifies it.
Water
Freeboard and balance
Radar level on the decant against a current stage-storage curve, metered decant return, and a full weather station that also supplies the barometric reference the sealed piezometers need wherever the pore water they read is in hydraulic connection with the atmosphere.
Aerial survey
Surface, volume and thermal
Survey drone with LiDAR for bare-earth models through vegetation and a thermal payload for locating seepage on the wall face. Autonomous survey boat for pond bathymetry and stored volume.
Satellite
Wide-area displacement
InSAR at millimetric sensitivity, with two caveats we state before you buy it. It measures along the satellite line of sight rather than in true three dimensions, and coherence is poor over an actively deposited beach. Peer-reviewed analysis of six failed and at-risk facilities retrieved only one-dimensional line-of-sight displacement in every case, and at one facility found a complete absence of data points along the section that subsequently breached. The part that failed was the part the satellite could not see.

We therefore treat it as a screening layer, not a monitoring solution, and we produce a site-specific InSAR coverage map as a standard deliverable: where measurement points can actually be retrieved on your facility, where they cannot, and precisely what ground instrumentation closes each gap. Corner reflectors recover coherence on the beach; ascending and descending passes recover more of the movement direction.
Delivery line
Where the dam is actually built
Underflow density and flow, pump vibration and motor current, pipeline pressure gradient and wall thickness, velocity held above the deposition velocity, and valve position on every discharge point.
Connectivity
Live within hours
Solar LoRaWAN gateways with dual-SIM cellular and satellite fallback, edge buffering at every node, and an outbound-only encrypted path with no inbound route to the mine OT network.
Asked and answered honestly / Wall cyclones
If your wall is built from cycloned sand, monitor the cyclones. If it is not, do not spend the money.

Where a facility is raised with cycloned sand, the cyclone battery is not process equipment. It is the machine that manufactures the structural shell, and the fines content of its underflow sets the permeability and the drained strength of what gets placed. An apex wears open continuously, a roping cyclone is invisible from the control room, and a shift-based laboratory sand check is an order of magnitude slower than either. We instrument per cyclone: feed pressure on each inlet, feed density and flow on the manifold, acoustic roping and wear detection, and a fines content soft sensor calibrated against the routine laboratory result. The laboratory becomes the calibration, not the control signal.

Where the facility is spigot-deposited with no cycloned sand in the wall, we will tell you not to. The same capital placed into piezometer density, or into resolving the phreatic surface on more sections, does considerably more for your risk profile. Recommending instrumentation that does not change a decision is how monitoring programmes lose their budget, and we would rather keep yours.

Where the value lands

We do not publish a generic percentage return, because the honest answer depends on your facility, your raise method, your water price and what sits downstream. We publish the mechanism. During the audit we size each line against your own numbers and put them into the signed baseline.

Decision
How it is made today
How it is made on live measurement
Underflow density target
Set once, adjusted when the beach visibly shortens. Entrained water loss never quantified.
Held as a controlled variable against beach slope and water recovery. Every point of solids is water returned to the plant instead of buried in the deposit.
Rate of rise
A consequence of the throughput decision. The consolidation constraint is a design document, not a live number.
A constraint visible in the production meeting, computed from measured pore pressure and measured dissipation. The tonnage call becomes an informed one.
Water returned to the plant
Whatever the decant pumps happen to return. The balance does not close, so the loss is unattributed.
A closed balance with every stream metered, so seepage, evaporation and entrainment separate out and each becomes a target you can work on.
Remaining life and the next raise
Estimated from a stage-storage curve drawn at commissioning and a nominal density. Capital committed early on conservative assumptions.
Computed from the surveyed surface, the measured in-situ density and the real deposition history. Capital committed on evidence, and where evidence supports it, deferred.
Escalation and reporting
A judgement assembled by hand from a monthly reading set, and defended from memory. Reporting costs days of engineering time per site.
Triggered automatically against your defined threshold, with attribution, evidence, a named owner and an audit trail already attached. Governance packs assemble themselves.
Avoided catastrophic loss
Managed by inspection interval and professional judgement, with the facility unobserved between readings.
The dominant term on any facility with people or infrastructure downstream. It is not insurable and it is not recoverable. Continuous observation is the only lever that moves it.
Governance and Accountability

We produce the evidence. Your Engineer of Record produces the judgement.

Tailings governance assigns named accountable people, and no software changes that. The Engineer of Record owns the design and the interpretation. The Responsible Tailings Facility Engineer owns day-to-day management. The Accountable Executive owns the risk at board level. Axiom is none of those roles and does not seek to be.

Reporting is structured against the frameworks you are actually held to, and against the part of them that can be tested. The Global Industry Standard on Tailings Management, published in 2020 and now under the custodianship of the Global Tailings Management Institute, comprises six topic areas, fifteen Principles and 77 auditable Requirements. The Standard's own Preamble states that the Principles "are intended to summarise the Requirements that follow and are not in themselves auditable". We map every detection, every threshold and every piece of evidence to the named, numbered Requirements, because a conformance claim made against a Principle is a claim against an object no auditor can test. Your Trigger Action Response Plan, which is the mechanism that turns a measurement into an action and which every detection in our stack maps onto. In South Africa, SANS 10286, the residue stockpile regulations under the National Environmental Management: Waste Act, and the dam safety provisions of the National Water Act where your facility falls within their scope.

Two commitments follow, and we hold both. Every automated output is reproducible from its raw inputs, because a governance record that cannot be reconstructed is not a governance record. And no automated system is positioned as a substitute for the statutory inspection regime, the independent technical review, or the professional judgement of the Engineer of Record.

A facility measured once a month is unobserved for the other twenty-nine days. Every decision taken in that interval rests on an assumption.
The operating principle behind the Axiom tailings platform
Peer-reviewed, and local
South African practice and the Standard are measurably far apart, and it is published.

A review of South African tailings monitoring practice in the SAIMM Journal found instrumentation "limited to standpipe piezometers", with drain flow measured manually on a monthly cycle. The Global Industry Standard on Tailings Management requires "electronic monitoring systems and…real-time monitoring", with "vibrating wire piezometers at critical areas".

That is not our characterisation of the market. It is a peer-reviewed statement, in a South African journal, of the exact distance between what most facilities in this country currently measure and what the Standard they are being audited against requires. The gap is the work.

Dladla, N. and Ramsamy, M., 2022. Journal of the Southern African Institute of Mining and Metallurgy, 122(6), June 2022.
Engagement-Scoped
Sensor count, section locations and detection thresholds are sized against your facility's risk assessment during the audit, then committed against a signed performance baseline. The architecture is public. The plan for your facility is engagement.
Where a tailings engagement starts

Tailings Evidence Review

Ninety minutes, complimentary, with a technical principal. One question: what can this facility currently prove about itself between inspections? We walk your instrument set, your survey record and your TARP against what each trigger would actually need in order to fire, and you leave with a documented short-list of where the evidence is thin. No commitment, nothing invoiced.

ThenFacility Evidence BaselineFour to six weeks, scoped against your facility then fixed. Instrument fitness register, balance closure attempt, a gap register against the 77 GISTM Requirements, and every TARP trigger mapped to a detection layer.
Signed by
Terrence Davhana, Technical Director. Owns the detection architecture, the instrument specification and the governance reporting on this practice. Every engineering decision about the facility itself remains with your Engineer of Record and your Responsible Tailings Facility Engineer, and nothing on this page changes that. What we sign for is the evidence they are given.
How this connects to the rest of the plant
Tailings is not a separate business from mineral processing. It is the same water, the same solids and the same control problem, one unit operation further down. The thickener underflow density that sets your beach slope is a dewatering control variable. The water returned from the decant is makeup water the concentrator does not have to buy. Axiom engages the whole chain as one system, and the six-phase discipline set out under Our Framework applies to a tailings facility exactly as it applies to a concentrator.
Start the conversation

A 90-minute review can establish what this facility can currently prove about itself.

Complimentary, no commitment. We walk your instrument set, your survey record and your Trigger Action Response Plan against what each trigger would actually need in order to fire, and surface where the evidence is thin.

Axiom Capability

Reliability Engineering

RUL Forecasting TMM Lifecycle Condition Monitoring Computer Vision

Probabilistic asset health, computer vision inspection, and lifecycle intelligence for the equipment your business actually depends on.

Predictive maintenance done properly is not a dashboard. It is a probability distribution, a financial impact, a lead-time-aware action trigger, and an audit trail. We build reliability platforms that translate raw maintenance records, sensor telemetry, and inspection imagery into the same currency the business actually speaks: forecast failure dates with calibrated confidence, the Rand exposure of each one, and the decision the engineer should take this week to defend the production plan.

/RUL FORECASTING
Probabilistic Remaining Useful Life
Every monitored component carries a Remaining Useful Life expressed as a full probability distribution, not a single date. We combine Weibull Accelerated Failure Time models with Cox Proportional Hazards for asset-specific covariates, then layer gradient-boosted regressors and isotonic calibration on top so that a stated 70% probability of failure within 30 days corresponds, empirically, to a 70% observed failure rate. Decision-grade outputs, not decorative dashboards.
Weibull AFTCox PHCalibrated
/TMM LIFECYCLE
Trackless Mobile Machinery Sentinel
A purpose-built lifecycle intelligence platform for the haul fleet, LHDs, drill rigs, and surface mobile equipment that move the orebody. Sentinel ingests usage hours, ERP inventory, OEM service specifications, and free-text technician comments through a governed schema; resolves asset identity through fuzzy matching; and produces RUL forecasts, automated risk referrals, and a 12-month rolling CAPEX waterfall. Sensor-ready, sensor-optional, mining-aware by design.
Asset MasterRisk ReferralsCAPEX Waterfall
/CONDITION MONITORING
Vibration, oil, and thermography pipelines
Streaming pipelines for the rotating equipment population, motors, gearboxes, pumps, fans, and mill drives, fusing vibration spectra, oil debris and viscosity data, and infrared thermography into a single asset health score. Bearing fault frequencies tracked through envelope analysis; wear debris ferrography mapped against trend; thermography deltas referenced to fleet baselines. Anomalies surface days to weeks before catastrophic failure.
FFT / EnvelopeFerrographyThermography
/COMPUTER VISION
Drone inspection, Mask R-CNN segmentation
Where the asset cannot be instrumented economically, we inspect it visually at scale. Drone-acquired imagery and video are passed through Mask R-CNN instance segmentation pipelines tuned per asset class: conveyor structures and idler populations, stockpile and dump geometry, slurry and return-water pipe routes, headgear and steelwork, and the crest, berms and spillways of a tailings facility between formal inspections. Every detection is timestamped, geolocated, and rolled into a maintenance schedule the planner can act on.
Mask R-CNNUAV SurveyDefect Detection
/INSTRUMENT RELIABILITY
The measurement network is an asset population
Every instrument the control layer and the governance record depend on is itself an asset that degrades, and almost nobody maintains a reliability programme for them. We carry density gauges, magnetic flowmeters, piezometers, analysers, load cells and level instruments as a monitored population with calibration intervals, drift trends, signal-path health and failure history treated exactly as a pump population would be. A flowmeter that has quietly degraded does not trip an alarm. It corrupts every number derived from it, and it keeps doing so until somebody checks.
Calibration RegisterDrift TrendingSignal Path
/RISK AND CAPEX
Risk scoring, referrals, financial integration
Every monitored asset carries a live Risk Score combining failure probability, production impact, and modifiers for spare-parts availability and supplier lead time. When the score crosses a defined threshold, Sentinel auto-generates a formal Risk Referral with the full RUL distribution, SHAP feature attribution explaining the model's reasoning, current inventory status, and a recommended action. The 12-month rolling CAPEX waterfall aligns maintenance spend with cash-flow planning, eliminating the budget surprises that follow unplanned breakdowns.
SHAP ExplainableRisk ReferralCost-Sensitive
Engineering Principle
We start where the data is. First-day usefulness from Excel maintenance records and OEM manuals, with no precondition that sensors be deployed before the work can start. Sensor-ready, sensor-optional. When the operation chooses to instrument the fleet, no re-architecture is required: the data model already accommodates IoT telemetry, vibration streams, drone imagery, and ERP integration through the same governed schema. The detailed treatments in the canonical reliability engineering literature, including the international standards on asset management and condition monitoring, ground every choice we make.
Signed by
Terrence Davhana, Technical Director. Owns the reliability practice with the CEO, from the governed asset schema through to the risk referrals and the CAPEX waterfall that reach the planner. Deliverables on this practice that carry an engineering judgement are signed by a named engineer.
The asset base this practice is built around
Mining and metallurgical plant: mobile fleet, fixed plant rotating equipment, materials handling, and the instrument population the process and governance layers depend on. The same methods run unchanged on a different asset population under Energy and Utilities, covering transformers, switchgear and renewable installations, and on the critical path of a production line under Manufacturing. Where a request sits outside all three we will say so before quoting, rather than after.
Start the conversation

A 90-minute review can locate the single highest-value loop in your circuit.

Complimentary, no commitment. We review the data landscape, walk the historian against the control narrative, and surface the most economically significant intervention available in the next 60 days.

Axiom Capability

Energy and Utilities

Specific Energy Maximum Demand Time-of-Use Self-Generation HV and Rotating Assets

Energy is bought by one department and spent by another, and the number in between belongs to neither.

Procurement negotiates the supply agreement, manages the tariff and receives the invoice. Process operations decide how many kilowatt hours it takes to move a tonne through the mill or a charge through the furnace. Energy intensity is determined almost entirely by the second group, reported almost entirely by the first, and owned by neither. That gap is the work on this page.

What this practice covers, and what it does not
The loadComminution, pumping, ventilation, compressed air, materials handling and furnaces. Where the energy is actually spent, and the only place intensity can be changed.
The supplyTime-of-use structure, maximum demand, power factor and curtailment obligations, carried as constraints the control layer can see.
The hedgeSolar photovoltaic generation, battery storage and wheeling arrangements, dispatched against forecast load and the tariff calendar rather than against irradiance alone.
The hardwareTransformers, switchgear, rotating plant and renewable assets, carried as a monitored population with condition and remaining life.
We are a process and data practice, not an electrical engineering practice. We work on how energy is consumed, scheduled, forecast and accounted for. Electrical design, protection coordination, grid code compliance and the statutory sign-off on electrical infrastructure remain with your electrical engineer, and we will not represent otherwise to your board or your insurer.
The argument this page exists to make

One unmanaged half hour can set the price of the entire month.

Industrial supply agreements do not bill energy alone. They bill demand, and on most such tariffs the demand charge for a billing period is set by the single highest measured demand interval inside it, not by the average across the month. Two large drives that happen to start in the same interval do not cost a little more than two drives that start apart. They set a ceiling that every remaining hour of the month is then charged against.

The reason this survives is that a peak is an event, not a trend. It does not appear in a monthly energy report, it does not show up as a rising line on anybody's dashboard, and by the time the invoice arrives the interval that caused it is four weeks in the past and nobody can say which two drives it was.

Look at how the three billed quantities are owned and the gap becomes obvious. Energy rewards using less in total, and process operations can act on that. Time-of-use rewards moving load out of the expensive hours, and planning can act on that. Demand rewards never coinciding, and no single function on most sites is accountable for coincidence at all.

It is a scheduling problem with a control answer. Start sequencing, interlocks between the largest drives, and a demand forecast the control layer can see are ordinary engineering. They are simply nobody's job.

Three billed quantities, three different behaviours
Billed on
Rewards
Usually owned by
Energy
Using less in total
Process operations
Time of use
Moving load off peak
Planning and procurement
Maximum demand
Never coinciding
Nobody
Tariff structures differ by supplier and by supply agreement. We read yours rather than assuming one, and every constraint below is configured from your own document.
Two large drives start in one interval Coincident peak recorded Demand charge fixed for the period Every remaining hour billed against a peak nobody chose

What the layer actually controls

Each item below is a constraint or an objective handed to the same optimisation layer that runs the process, not a separate energy system bolted alongside it. Energy competes with throughput and recovery inside one problem, because on a real plant that is what it does.

Intensity
Specific energy as a controlled variable
Kilowatt hours per tonne treated, carried live per unit operation rather than reconciled monthly against a production figure. Comminution is typically the largest single electricity consumer on a concentrator, which makes mill loading, media charge and classification efficiency energy decisions as much as metallurgical ones. An intensity number that arrives monthly cannot be controlled, only regretted.
Coincidence
Maximum demand as a hard constraint
Start sequencing and soft interlocks between the largest drives, a rolling demand forecast inside the billing interval, and a stated ceiling the optimisation layer is not permitted to cross. The plant chooses which load waits thirty seconds. The alternative is that the tariff chooses, once, and charges for it all month.
Scheduling
Time-of-use load shaping
Discretionary load, meaning milling against stockpile, reclaim, pumping, compressed air and non-critical utilities, scheduled against the tariff calendar and the production plan together. Only load that is genuinely discretionary is moved, and the constraint that makes it discretionary is written into the model rather than assumed.
Furnace
Where energy and metallurgy are the same decision
On a submerged-arc furnace the energy question and the process question cannot be separated: electrode position, resistance, power factor and charge composition move specific energy, electrode consumption and metal recovery simultaneously. That work is set out in full under Pyrometallurgy, and it is led by the same engineer.
Self-generation
Dispatch against load, not against sunshine
Where photovoltaic generation and battery storage are installed, the dispatch decision is a forecasting problem in three parts: generation, plant load, and the tariff period the next interval falls into. Storage charged on irradiance alone will routinely be full when it is cheap and empty when it is not.
Curtailment
A shed order the plant chose in advance
Where supply is interruptible or curtailment is a contractual obligation, the load-shedding order is agreed in writing with metallurgy and maintenance before it is ever needed, ranked by production consequence and restart cost. A shed order decided during the event is decided by whoever answers the telephone.
What has to be true first
You cannot shape a load you cannot see at the resolution the tariff bills at.

Demand is billed on an interval. If the plant historian stores that measurement at a coarser interval than the one the utility settles on, or a compression deadband removes the short excursions, then the peak that set your charge is not visible anywhere in your own data. You are then arguing about an invoice using evidence that cannot resolve the event it is about.

Before any load shaping is designed we check the metering interval against the settlement interval, the instrument transformer ratios actually installed against the ones in the drawings, the historian scan rate, compression and deadband, and whether the plant's own meters can be reconciled with the utility meter over a closed period. Where they cannot be reconciled, we report the residual and stop. An energy saving claimed against metering that does not close is not a saving, it is a rounding difference with a business case attached.

The asset side of the same practice

Energy infrastructure carries a high consequence of failure and a maintenance regime that is still frequently calendar-driven. The reliability methods set out under Reliability Engineering apply here without modification, on a different asset population.

HV assets
Transformers and switchgear
Loading history, thermal duty, dissolved gas and partial discharge trends carried as a condition record rather than a periodic test result, with remaining life expressed as a distribution and every risk score reported alongside the features that drove it.
Rotating plant
Motors, pumps, fans, compressors
Vibration spectra, oil debris and viscosity, and infrared thermography fused into one asset health score. Bearing fault frequencies tracked through envelope analysis, thermography deltas referenced to a fleet baseline rather than to an absolute threshold.
Renewables
Inspection that ends in a dispatch decision
Drone-acquired imagery through instance segmentation pipelines tuned per asset class: photovoltaic arrays for soiling, hot spots and cracked cells, turbine blades for leading-edge erosion and surface defects. Soiling and defect maps drive cleaning and rope-access campaigns sized to the fault population and the generation actually being lost, rather than to a fixed calendar.
The boundary of this practice
We do not design electrical infrastructure, we do not perform protection coordination or grid code compliance studies, and we do not sell, specify exclusively or take commission on generation, storage or metering equipment. Where a measurement or an asset is genuinely required we name the requirement and not the supplier. Our deliverable is the scheduling, forecasting, control and accounting layer that sits above equipment your electrical engineer owns.
Energy is not a separate system
It is a cost attached to every unit operation on the plant, which is why it is not managed here in isolation. The single largest consumer sits in comminution, the highest intensity per tonne sits in the furnace, and the assets that deliver it are carried by the same reliability methods as everything else that turns.
Signed by
Terrence Davhana, Technical Director, on the load, tariff and forecasting work, and Helly Nkhuna, Director, Pyrometallurgy, wherever the load in question is a furnace. This practice is deliberately scoped to how energy is consumed and scheduled on a metallurgical plant, which is the ground we hold. Deliverables that carry an engineering judgement are signed by a named engineer.
Engagement-Scoped
The metering reconciliation and the tariff constraint model are established during the audit, then committed against a signed performance baseline. The architecture is public. The constraint set for your supply agreement is engagement.
Start the conversation

A 90-minute review can establish whether your metering can settle an argument about your own invoice.

Complimentary, no commitment. We walk the supply agreement against the plant's metering and historian, and you leave with a documented short-list of where the energy evidence is thin and which constraint is worth writing into the control layer first.

Axiom Capability

Manufacturing

Inline Quality Line Control Changeover OEE Digital Twin

By the time the quality result comes back, the product already exists.

In most plants the authoritative quality measurement arrives after the material has been made: a laboratory result, an end-of-line tester, a coordinate measurement, an inspection panel. Everything upstream of it runs on the assumption that the last good result still holds. That assumption is usually correct. What it costs on the occasions it is not is carried as scrap, rework, concession and a downgraded batch nobody can explain.

Where these methods transfer, and how well
Continuous processCement, lime, chemicals, pulp and paper. The closest transfer, because the physics and the control problem are the ones this practice was built on.
Batch processFood, beverage and formulated products, where the control problem is the recipe and, more often, the transition between two of them.
Converting and webCoating, laminating and extrusion, where quality is a continuous property of a moving substrate and defects have a spatial signature.
High-volume discreteAssembly and machining, where the measurement is dimensional, the failure mode is drift, and the data problem outweighs the process physics.
We are strongest on continuous and batch process, and we will say so before you engage us rather than after. That is where the physics resembles the circuits this practice was built on, and where our estimators carry first-principles structure rather than pattern alone. On high-volume discrete assembly we bring the data, reliability and vision methods rather than the process physics, and the scope will name which of the two you are buying.
The argument this page exists to make

A control loop closed by a laboratory is not a control loop.

Follow the sequence. A setpoint is held. Material is produced. A sample is drawn. It travels, it queues, it is prepared, it is measured. A result returns. Somebody decides. A correction reaches the line.

Every unit produced between the sample being drawn and the correction landing was made on an assumption, and it was already committed before anyone could know whether the assumption held. Widen the interval and you have not made a worse product, you have made an unmeasured one. The plant is not out of control in those hours. It is simply unobserved, and those are not the same condition even though they look identical on a trend.

This is structurally the same problem as a residue assay in a leach circuit, and it takes the same treatment. Build an estimator from measurements that already exist and already move at the speed of the process, hold it to a published accuracy floor before it is allowed to change anything, and then demote the laboratory from the thing that closes the loop to the thing that calibrates the estimator. The laboratory does not disappear. It stops being the bottleneck in a feedback path it was never designed to sit in.

The honest constraint is that this only works where the fast measurements genuinely carry the information. Where they do not, we will tell you the estimator does not clear its floor and scope a narrower objective instead of forcing one.

Three measurements, and what each can honestly be used for
Measurement
Arrives
What it can do
Laboratory or end of line
After the material exists
Confirm, reject, and calibrate
Inline instrument
Continuously, where one exists
Control, subject to its own fitness
Soft sensor
Continuously, always
Control, against a published floor
The floor is stated on the What We Publish page and it is not negotiable per engagement. An estimator that does not clear it is not permitted to move a setpoint, and we report that outcome rather than relaxing the standard.
Setpoint held Material produced Sample drawn and queued Result returned Everything made in between was made unobserved

What the layer actually does on a production line

The architecture is the one described under Our Framework, applied to a line rather than a circuit. A healthy base control layer at the foundation, detection guarding it, estimators above that, control above those, and an optimisation layer at the top that recommends rather than imposes.

Quality
Inline soft sensing where no inline measurement exists
A continuous estimate of the property that actually defines saleable product, built from the process measurements the line already produces and anchored where possible on a mass or energy balance rather than on correlation alone. Reported with a prediction interval, and with a validity check so it declares when it is extrapolating instead of returning a confident number from outside its own experience.
Control
Holding the line at the constraint, not near it
Most lines run with a margin against specification because the operator cannot see how close they are. A trustworthy continuous estimate lets that margin be reduced deliberately and by a stated amount rather than accidentally. The give-away is almost always in the margin, and the margin exists because of the measurement gap.
Transitions
Changeover is where the off-spec is made
Steady state is usually the well-controlled part of a line. Grade changes, recipe transitions and start-up are where the scrap is produced, and they are typically run to a written procedure rather than to a controller. We model the transition itself so the path between two grades is optimised, not merely survived.
OEE
Decomposed, with the denominator stated
Availability, performance and quality reported separately and continuously, with the time basis defined in writing, plus which constraint bound in each period and for how long. The aggregate is a scoreboard. The decomposition is the instruction, and only one of the two tells an engineer what to do on Monday.
Energy
Cost per unit produced, not per month
Specific energy and specific utility consumption carried per unit of saleable output and per grade, so the true cost of a slow-running line or a marginal product is visible while it is happening. The tariff and demand constraints are the ones set out under Energy and Utilities.
Availability
Prediction on the critical path only
Remaining useful life forecasting and condition monitoring concentrated on the equipment that actually constrains output, with failure probability expressed as a distribution and a stated production consequence. Monitoring everything equally is how a reliability programme becomes a reporting exercise.
A position we will defend
An OEE figure without its three components and a stated time basis is not a measurement.

Overall Equipment Effectiveness is a product of availability, performance and quality. Multiplying them destroys the information an engineer needs, because two lines can report an identical figure for entirely unrelated reasons and the number gives no indication which. Worse, the choice of time basis, whether the denominator is calendar time, scheduled time or planned production time, moves the result substantially without a single thing changing on the line.

We therefore publish the three components separately, state the time basis inside the definition rather than in a footnote, and report which constraint bound in each period and how often. Where a line's figure improves because the denominator changed, we say that is what happened. This is the same standard applied everywhere else on this site: a number that cannot be tested against is not worth reporting.

The boundary of this practice
We do not implement or replace a Manufacturing Execution System, an ERP or a quality management system, and we do not compete with your existing line control. We build above them, and everything we install has a documented reversion path back to them. Statutory product conformity, batch release and the professional decisions of your quality function remain entirely with your quality function, and no estimator we build is positioned as a substitute for a release test. Where a regulated environment requires validated computerised systems, that validation is a scope item to be agreed in writing before anything is built, not an assumption.
The same architecture, a different asset
Nothing on this page is a separate product. It is the framework applied to a line, with the estimator discipline, the detection stack and the published floors carried across intact. The two practices it leans on most are below.
Signed by
Terrence Davhana, Technical Director. Owns the estimator and control work on this practice, and the decision about whether a proposed soft sensor can clear its floor on your measurements before anything is built on it. Deliverables that carry an engineering judgement are signed by a named engineer.
Engagement-Scoped
Whether a quality soft sensor is feasible on your line is settled during the audit, against your own historian and your own laboratory record, then committed against a signed performance baseline. The architecture is public. The per-line configuration is engagement.
Start the conversation

A 90-minute review can establish whether a quality soft sensor is feasible on your line.

Complimentary, no commitment. We walk your process measurements against your laboratory record and the specification that defines saleable product, and you leave with a documented answer on whether the fast data carries the information, before anyone proposes building anything.

Axiom Capability · Live

Live Demonstration

A working Axiom controller, running right now

Advanced Process Control, demonstrably operational.

This is a real Axiom controller, running live in your browser. It manipulates air rate to hold froth velocity on setpoint, defending against ore-grade disturbance and sensor noise. Use the controls under the trends: toggle Ore change to inject a step disturbance, or Noise boost to inject high measurement noise, and watch it return the process to target without oscillation. This is the class of controller Axiom builds for flotation, comminution, and downstream metallurgical operations. The control code is real. The process it is controlling is a simulation running in this page. No plant data, no client data and no tag from any operation is used anywhere in this demonstration.

FrothVel_SP → 3×3 FLC + 7 modifiers → gate → AirRate_SP → air PID (perfect) → ore + noise → FrothVel_PV
FrothVel_PV
4.000
cm/s (CV)
FrothVel_SP
4.0
cm/s (setpoint)
AirRate_SP
45.0
Nm³/h (MV)
Jg
0.81
cm/s
Err
0.000
cm/s
DeltaErr
0.000
cm/s
FrothDepth 165 mm
FrotherDose 70.0 g/t
FeedSolids 35.0 %
CollDose 32.0 g/t
pH 8.50
OreChange inactive
FinesFrac 22.0 %
Eh/ORP -100 mV
NoiseIdx 0.20
CamConf 0.90

FrothVel_PV vs SP (cm/s)

AirRate_SP, manipulated variable (Nm³/h)

3×3 rule base, singletons {−3, −1.5, 0, +1.5, +3} Nm³/h

Modifier trims + gating

SP: 4.0 cm/s
Presets:
Engage with us

Let us build you a controller
that earns its place on the plant.

If your circuit is losing throughput to loop oscillation, sticky valves, drifting sensors, or a DCS that fights the plant, we can help. Every Axiom engagement begins with a Complimentary Circuit Data Audit. Once your foundation is stable, we build the robust multivariable controller that stabilises your circuits so you can optimise them for measurable performance gains.

Process Technology / Technical Documents
Volume 01 / Public Release

Soft Sensor Architectures
for Mineral Processing Control.

A two-paper compendium on physics-informed soft sensors that close the latency between laboratory measurement and real-time process control. Designed as feedforward inputs to the Axiom hybrid Advanced Process Control layer, with operator-approved supervisory optimisation above. Authored by Axiom for public release; the methods are deployed under engagement on industrial sites.

Compendium: Volume 01
The complete two-paper bundle in a single document. Foreword, P-001, P-002, and consolidated reference list.
Download Volume 01
Technical Paper P-001
A Physics-Informed Soft Sensor for Real-Time Ore Hardness Estimation in SAG Mills

A residual-based architecture combining the Morrell mill power model with Extra Trees regression, delivering a continuous, SCADA-only hardness signal suitable for Model Predictive Control feedforward. Extended to a geospatial mine-to-mill digital twin through Kalman fusion of blast block models, shovel GPS, and stockpile blending.

AuthorsT. Davhana, D. Mthimunye Pages04 ClassificationPublic Release
Download P-001
Technical Paper P-002
An Ensemble Soft Sensor for SiO2 Grade Prediction in Iron Ore Reverse Cationic Flotation

A T+30 minute concentrate-grade prediction architecture stacking LSTM, 1D-CNN, and Random Forest models on physics-derived, reagent-intensity, and temporal-lag features. A ridge meta-learner produces both a point estimate and a 95% prediction interval, with SHAP attribution for metallurgist explainability.

AuthorsT. Davhana, D. Mthimunye Pages04 ClassificationPublic Release
Download P-002
Volume 02 / In preparation

Measurement Validity
and Facility Evidence.

Two papers in preparation on the other half of the problem: not what a model can infer, but whether the measurements underneath it can carry the inference at all. Neither is published yet, and neither is available for download. They are listed here because we would rather state what is coming than let an empty page imply the library is finished.

Technical Paper P-003 · [FORTHCOMING]
Error Amplification from Slurry Density Measurement to Rate of Rise

The algebra set out on the Dewatering and Water page, developed in full: how a relative error on a density gauge propagates through solids fraction, dry tonnage and rate of rise, why the amplification worsens at the low densities most tailings streams run at, and what calibration interval that arithmetic actually implies.

Authors[TBC] Target[DATE TBC] StatusIn preparation
Technical Paper P-004 · [FORTHCOMING]
System-Level Performance Floors for Tailings Monitoring Networks

A proposed reporting standard for what a deployed monitoring system achieves on a live facility, as distinct from what its instruments achieve on a datasheet: false-alarm rate per instrument-month, time to detect against a named rate of change, and minimum detectable change at the wall after transmission gaps, outages and drift.

Authors[TBC] Target[DATE TBC] StatusIn preparation
Privacy Policy · P-PRV-01
Our POPIA-aligned privacy policy, governing the operational and personal data we touch under engagement. Available as a web page or as a PDF for your procurement and legal review.
Download the Policy
Security One-Pager · P-SEC-01
One side of A4 on the reference architecture, the write-back contract, ownership, termination, failure behaviour and audit. Written to be forwarded to an OT security lead without editing.
Download the One-Pager
Distribution.   These papers are released for public distribution and may be redistributed in unmodified form. The underlying methods are deployed under engagement on industrial sites; the papers describe the architecture, not the proprietary tuning that the engagement delivers.
Companion document.   See also our Privacy Policy, POPIA-aligned, governing the operational and personal data we touch under engagement.
Axiom Governance

What We Decline

The work we turn down is the clearest statement of how we work.

Scope that will not pay
Where the analysis shows a proposed intervention will not repay its cost at this operation, we say so and decline it. Including when the client has already decided they want it, and including when it is the larger piece of work.
Optimisation on an unstable base
No layer is engaged above a regulatory foundation that has not passed the readiness check. An optimiser layered on an unstable base amplifies the instability rather than absorbing it.
Reinforcement learning on live circuits
Very few production deployments exist in mineral processing and the validation story is not yet sound: a policy that learns by exploring must operate the plant badly in order to learn. We use constrained predictive control with uncertainty-aware margins instead. We will revisit this position when the evidence changes, and we will say so publicly when it does.
Replacing your control system
We build above the DCS, never inside it. Nothing we install competes with your existing regulatory control, and everything we install has a documented reversion path to it.
Selling you anything with a serial number
We cannot sell you a sensor, a mill, a filter press, grinding media, a flotation cell or a DCS, because we make none of them. There is no product line, no distribution agreement and no commission arrangement anywhere in this business, so there is no version of our advice that pays us more than another version. Where a measurement is genuinely required we name the requirement and not the supplier, and the choice of manufacturer stays with you. This is not a stated value. It is what our invoice is structurally capable of containing.
Claims a baseline cannot test
Nothing is invoiced against a number the signed baseline is incapable of measuring.
Engineering accountability
Deliverables that carry an engineering judgement are signed by a named engineer. When a model underperforms, there is a person who answers for it and a defined process by which it is re-identified or withdrawn.
Start the conversation

A 90-minute review can locate the single highest-value loop in your circuit.

Complimentary, no commitment. We review the data landscape, walk the historian against the control narrative, and surface the most economically significant intervention available in the next 60 days.

Axiom Governance

What We Publish

Everyone publishes what a sensor can do in a laboratory. Nobody publishes what the system does on a live facility.

Instrument accuracy is well documented across this market. Millimetre figures for shape arrays, sub-millimetre for slope radar, stated ranges for piezometers. Every one of those numbers describes a device under controlled conditions. None of them describes what you actually get at the wall after transmission gaps, power outages, calibration drift and a wet season. That second number is the one that decides whether an alarm can be trusted, and it is the one we commit to publishing.

System-level performance floors

For any monitoring deployment we commit to publishing the following, per facility, on a stated cadence. These are the numbers a system can be tested against, which is the whole reason to publish them.

Floor 01
False-alarm rate
Alarms raised that did not correspond to a real change, expressed per instrument-month. Published per detection layer, so a noisy layer cannot hide inside an aggregate. An escalation process nobody trusts is worse than none, and this is the number that determines which you have.
Floor 02
Time to detect
Elapsed time from the onset of a defined rate of change to a raised, attributed alarm. Stated against a named rate rather than in the abstract, because detection latency is meaningless without the signal it is detecting.
Floor 03
Minimum detectable change at the wall
Not the instrument specification. The change actually resolvable after transmission gaps, outages and drift, on that facility, with that network. This is the figure that differs most from the datasheet, and the one nobody publishes.
Floor 04
Data completeness and uptime
Percentage of expected readings actually received, per instrument, and platform availability. Reported alongside the gaps rather than after interpolating over them.
Floor 05
Confidence intervals on TARP inputs
Any number that enters a Trigger Action Response Plan carries a stated confidence interval. A threshold crossed by a value with unquantified uncertainty is not a decision, it is a guess with a timestamp on it.
Floor 06
Adoption, including the unflattering
Acceptance rate by shift, implementation rate, the reasons recommendations were rejected, controller uptime, and which constraints bound and how often. Published for every installation. An optimisation layer running at a twenty percent acceptance rate is not an optimisation layer.

The estimator floor, restated

This standard is published in full on the Mineral Processing page, where it belongs alongside the control hierarchy it governs. It is restated here because it is the other half of the same commitment. No vendor surveyed in this market publishes any model accuracy metric at all, while all of them sell soft sensors.

A published accuracy floor
R² of at least 0.85 on held-out future periods before an estimate is permitted to move a setpoint, with RMSE and MAE both reported. A gap between them means a few large failures rather than uniform error, which is why we publish both.
Stratified, not pooled
Performance broken out by operating mode and feed classification. A model can clear the floor overall and fail completely on one feed type, and the pooled figure conceals exactly the conditions in which the controller most needs the estimate to hold.
Calibrated uncertainty and a validity domain
Prediction-interval coverage demonstrated on held-out data, and a validity-domain check so the estimator declares when it is extrapolating rather than returning a confident number from outside its own experience.
Why this page exists
A system-level number can be tested against. That is the reason it is not published, and the reason we publish it.

An instrument specification is a claim about a device in a laboratory, and it is safe to publish because no operating facility can falsify it. A false-alarm rate per instrument-month on a named facility is a different kind of statement. It can be checked, argued with, and held against us at the next review.

We take the view that a monitoring system nobody can test is a monitoring system nobody should buy, and that applies to ours. Where a floor is missed, the number is published missed. That commitment is worth more than any figure we could put next to it.

The published record

Every figure on this site carries one of exactly two labels: Achieved, with the commodity, the year and the words measured against a signed baseline, or typical industry range, with the source cited. A number that can be given neither label is deleted rather than softened. This table is the record. It is short, and it will only lengthen when a closed engagement produces a figure that can carry one of those two labels.

Figure
Label
Basis
+3% absolute PGM recovery uplift
Achieved
PGM, 2025, measured against a signed baseline. Data-driven flotation and regrind circuit stabilisation.
R² ≥ 0.85 on held-out future periods
Published standard
A floor we hold ourselves to before an estimate may move a setpoint. Not an outcome claim.
Why the record is two rows long
Because two figures are all that currently qualify. The floors set out above are commitments about what we will publish once a deployment has produced it, not claims that the numbers already exist. A table padded with plausible industry figures would be precisely the practice this page exists to remove, so the record stays short and grows only when an engagement closes that earns it another line.
Start the conversation

A 90-minute review can locate the single highest-value loop in your circuit.

Complimentary, no commitment. We review the data landscape, walk the historian against the control narrative, and surface the most economically significant intervention available in the next 60 days.

Axiom Governance

Engagements

Five rungs, and every one of them ends somewhere you can walk away from.

Most engagements in this market open with a proposal for the whole programme, which asks a buyer to commit before anyone has established what the operation can currently prove about itself. Ours open with ninety minutes and a documented short-list. The ladder below is how we structure work, in the order we structure it. Every rung has a written scope agreed before it starts, a defined end point, and a deliverable that stands on its own even if you never take the next step.

Rung 01
Tailings Evidence Review or Circuit Data Audit
Ninety minutes, structured, with a technical principal rather than a salesperson. On a facility we answer one question: what can this facility currently prove about itself between inspections? On a plant: where is the single highest-value control or recovery opportunity in this circuit? It ends with a documented short-list. There is no commitment to proceed and nothing is invoiced.
Complimentary90 minutes
Rung 02
Facility Evidence Baseline
The piece of work that decides whether anything else is worth doing. Four to six weeks, deliberately sized small enough to be signed without a board paper. Quoted against your facility once we have seen it, then fixed, so the number does not move while the work is running. Four deliverables, each of which stands on its own even if we never work together again.
  • Instrument fitness register. Every instrument the evidence depends on, audited against calibration, installation, signal path, resolution and physical condition, with what fails and what it costs to fix.
  • Solids and water balance closure attempt. Two independent measurement chains against one physical quantity. They close to a defensible tolerance or the residual is quantified and bounded in writing.
  • Gap register against the 77 GISTM Requirements. Mapped to the numbered, auditable Requirements rather than to the Principles, with the evidence you currently hold for each and the evidence you do not.
  • Every TARP trigger mapped to a detection layer. Which triggers are currently detectable, at what latency, by which instrument, and which are written into the plan with nothing behind them.
Quoted, then fixed4 to 6 weeks
Rung 03
Pilot
One section, one failure mode, three to six months. A countersigned baseline before anything is built, success criteria agreed in advance, and detection running in parallel with your existing inspection regime rather than instead of it. Scoped narrow on purpose, because a pilot that cannot fail cannot prove anything either.
Scoped3 to 6 months
Rung 04
Programme
Full facility, then scale-out across facilities. Instrumentation extended from the governing sections to full coverage, TARP linkage enabled with named owners and required response times, and governance reporting automated for the Engineer of Record, the Responsible Tailings Facility Engineer and the Accountable Executive.
ScopedPer facility
Rung 05
Monitoring and governance subscription
Recurring. Detection running, performance floors published on the agreed cadence, instrument network health reported as a first-class metric alongside the facility, and thresholds revisited after every raise. You own the models, the code and the right to evolve them throughout, so this is a service you continue because it is working rather than because leaving is expensive.
RecurringAnnual
Why we scope rather than publish a rate
A published rate for work this variable would be a marketing figure, not a price.

No two operations present the same job. A single instrumented section on a small facility and a programme across four facilities are not comparable pieces of work, and the instrument set we find on arrival changes the scope of everything built above it. A single published number would mean either quoting high enough to cover the worst case we might walk into, or quoting low and repricing once the work exposes what is actually there. We are not willing to do either.

What we will commit to before you have spent anything. The first rung costs nothing. The scope of every rung above it is written down and agreed before that rung starts. And nothing is invoiced against a number the signed baseline is incapable of measuring.

What we will not invoice against
Nothing is invoiced against a number the signed baseline is incapable of measuring. Where the analysis shows a proposed intervention will not repay its cost at your operation, we say so and decline it, including when it is the larger piece of work. The full position is set out under What We Decline.
Start at rung one

Ninety minutes, complimentary, with a technical principal.

A Tailings Evidence Review for a facility, a Circuit Data Audit for a plant. Both end with a documented short-list and neither creates an obligation.

Axiom Governance

How We Measure Value

Ore moves. A before-and-after comparison is not evidence.

Feed grade, mineralogy, hardness and market conditions all move underneath any comparison, and they move on the same timescale as the improvement being claimed. A difference measured before and after a controller was switched on is therefore not evidence that the controller caused it. We use three methods together, and we publish which one produced which number.

Method 01
Randomised on and off trials
The controller is enabled and disabled on a randomised schedule across several weeks. Paired comparison removes slow drift in feed conditions, and this provides the primary evidence.
Method 02
Cross-sectional comparison
Where an operation runs parallel equipment on common feed. Controller on one line, off the other, rotated on a schedule. Feed variability is common to both lines and cancels.
Method 03
Baseline model residual
A model predicts what the operation would have produced under the conditions actually observed, without the controller. The uplift is the residual. This generalises the trial result to the periods when no trial was running, and it is how the number is sustained after the trials end.
Reported alongside the metallurgy
Adoption is a number too, and we publish it even when it is unflattering.

Alongside the metallurgical result we report adoption: acceptance rate by shift, implementation rate, the reasons recommendations were rejected, controller uptime, and which constraints bound and how often.

An optimisation layer running at a twenty percent acceptance rate is not an optimisation layer, and we would rather say so than report the recovery number on its own.

How numbers are labelled on this site
Every figure published here carries one of exactly two labels. Achieved, with the commodity, the year, and the words measured against a signed baseline. Or typical industry range, with the source cited. A number that can be given neither label is deleted rather than softened. Four numbers a buyer can interrogate are worth more than eleven they cannot.
Start the conversation

A 90-minute review can locate the single highest-value loop in your circuit.

Complimentary, no commitment. We review the data landscape, walk the historian against the control narrative, and surface the most economically significant intervention available in the next 60 days.

Axiom Governance

Security and Data Governance

The connection is one-way, and the models are yours.

Our platform reads from your historian and writes, when and only when your operating team has authorised it, to a bounded set of setpoints inside limits your engineers have set. There is no inbound path to your operational technology network. There is no mechanism by which an outage on our side can affect your plant, because there is no dependency in that direction. Everything below is written to be forwarded to your OT security lead without editing.

Reference architecture

Zone 1 / Plant, your OT network
DCS, PLC and historian. Your equipment, your network, your access control. Nothing of ours is installed inside this zone.
Read historian, outbound only ↓  ↑ Write bounded setpoints, on authorisation
Zone 2 / Edge, the boundary
A single node that initiates every connection outward. It holds the write allow-list, the rate limits and the local audit log. If it is powered off, the plant runs exactly as it did before we arrived.
HTTPS on port 443, outbound only. No inbound path to OT, no open listening port, no remote session into the plant
Zone 3 / Platform
Model training, monitoring, dashboards and reporting. A failure here stops recommendations. It cannot stop, slow or alter your plant.
Standards
IEC 62443 and NIST SP 800-82
The architecture is designed to the zone and conduit model of IEC 62443, the standard for security of industrial automation and control systems, and to NIST SP 800-82, the guide to operational technology security. We engage your security team in week one of any engagement, not at commissioning.
Write-back
Gated, bounded, logged, reversible
Every write is authenticated against a named service identity, restricted to an explicit allow-list of tags, bounded inside limits your engineers set, rate-limited so no sequence of writes can move the plant faster than your team can react, and logged immutably. A documented reversion returns every affected loop to regulatory control at its last known good setpoint.
Ownership
Your data, your models, your code
You own your operational data, the trained models, the code, and the right to evolve all three independently of us. That is a term of the engagement, not a courtesy, and it is why we describe the hand-over as a deliverable rather than an exit.
Termination
No lock-in
On termination you receive your data in open formats, the model artefacts in a portable serialisation, the training and inference code, and the runbooks. There is no proprietary format that makes leaving expensive. A supplier that keeps the keys has an incentive you should not be paying for.
Failure behaviour
Loss of our platform is not a plant event
If our platform becomes unreachable, the edge node stops issuing recommendations and the control layer holds at its last authorised setpoint or reverts to regulatory control, according to the signal state contract published on the capability pages. Your operators are told which, and why.
Audit
Every action can be reconstructed
Reads, writes, model versions, authorisations, acknowledgements and reversions are all timestamped and retained for the life of the engagement. Any automated output can be reproduced from its raw inputs, because a record that cannot be reconstructed is not a record.
Security one-pager · P-SEC-01
Everything on this page on a single side of A4, written to be forwarded to your OT security lead without editing. Reference architecture, the six controls, and what we will not commit to in public.
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Data protection, residency and incident response
Axiom operates under a POPIA-aligned privacy policy governing the operational and personal data we touch under engagement. Data residency, the sub-processor register, and our incident response and notification commitments are stated in the engagement agreement and are available on request under NDA. We publish here only what we can commit to without qualification.
Start the conversation

A 90-minute review can locate the single highest-value loop in your circuit.

Complimentary, no commitment. We review the data landscape, walk the historian against the control narrative, and surface the most economically significant intervention available in the next 60 days.

Get in Touch

Contact

Start with a structured Circuit Data Audit, the typical entry point to an Axiom engagement.

The Audit is complimentary, 90 minutes, and ends with a documented short-list of the highest-value control, sensing, or recovery interventions available to your operation. There is no commitment to proceed.

Reach Us
A single point of contact for engineering, commercial, and consultation enquiries.
All enquiries are routed to a technical principal, not a sales queue. Response within one business day.
Office
65 Ehmke Street, Nelspruit 1201
Republic of South Africa
Phone
+27 78 261 6954 Direct line, business hours, South African Standard Time.
Email
info@axiomprocesstech.com For Circuit Data Audit requests and all technical engagement enquiries.
LinkedIn
axiom-process-intelligence Company updates, technical commentary, and engagement notices.
Coverage
Southern Africa, Sub-Saharan Africa, and selected international engagements by referral.
Entity
Axiom Process Intelligence (Pty) Ltd
Trading as Axiom Process Technology. CIPC registered.
Circuit Data Audit / Engagement Request
By submitting, you consent to Axiom Process Technology contacting you in respect of this request. No data is shared with third parties.