How simulator training prepares ALS2 control room operators

Operating an acidless separation plant that recovers precious metals from electronic waste is not a job someone learns by watching a senior colleague. The ALS2 process involves a chain of chemical, thermal and mechanical steps that respond to operator decisions in seconds, and a trainee who only sees the plant from the control room gallery will miss the underlying dynamics that decide whether a batch of printed circuit boards yields clean gold, silver and platinum group metals. The ALS2 project team understood this from the early stages of the Horizon 2020 programme, and that is why a dedicated training simulator now sits alongside the physical plant as a core piece of operator development infrastructure.

Australia offers a useful parallel. From the e-waste depots of Sydney and Melbourne to the legacy mining towns of Broken Hill and Kalgoorlie, the country has long wrestled with how to train technicians on processes too valuable or too hazardous to learn on the job. WEEE streams feeding ALS2 plants are growing fast as national recycling targets tighten, and Australian operators increasingly look at European refining innovations as a template. A simulator that can be run repeatedly, paused mid-shift, and reset without consuming reagents fits the Australian appetite for rigorous competency frameworks and high-trust safety cultures.

The training simulator for ALS2 plant control room operators is a software replica of the full process, built from the flow diagrams the engineering team used for commissioning. It mirrors the behaviour of the leaching cells, electrowinning circuits and precipitation reactors, and lets an instructor inject faults on demand: a blocked filter, a drifting pH probe, a sudden voltage sag on the rectifier. Trainees see how their moves affect downstream recovery rates, and learn the rhythm of an acidless cycle fundamentally different from the smelter routines taught in older Australian metallurgical courses.

This matters because the technology sits inside a sustainability story, not just a refining story. The ALS2 process avoids aqua regia and concentrated hydrochloric acid, so operators handle far less corrosive chemistry than their counterparts in traditional refineries. That shifts the risk profile considerably, but does not eliminate the need for skilled eyes on the dashboard. A clean, closed-loop recovery plant still depends on people who recognise the early warning signs of contamination, foaming or flow imbalance, and a simulator is the safest place to practise that pattern recognition before feed material is tipped into the hopper.

Why simulation became part of the ALS2 operator pathway

When the engineering consortium first mapped out the operator competency requirements, three pressures converged. Throughput came first: a compact precious-metals recovery plant destined for export markets including Australia must ramp up quickly once installed. Safety came second: although the chemistry is acidless, the plant still handles fine particulate dust, hot effluents and high-current rectification, and a procedural slip on day one can cost metal and morale. Cost came third: every litre of process liquor wasted during a learning curve is money out of the door, and nobody wants a trainee to discover what a mis-tuned dosing pump looks like on a live batch.

The simulator resolves all three pressures in a single package. Trainees can practise a full shift in the time it takes to drink a coffee in Brisbane's CBD, then debrief on the same screen with their instructor. They can be handed a scenario in which the resin elution column starts to channel, or in which the silver precipitation reagent runs low, and work through the recovery procedure without anyone being exposed to a real upset. For Australian sites that will eventually host ALS2 modules, this kind of repeatable practice is worth more than any classroom lecture on process control.

There is also a cultural shift at play. Australian vocational education has moved steadily towards competency-based assessment over the past two decades, and simulator sessions map neatly onto the evidence requirements for units of competency in process plant operations. An operator who has logged fifty hours of fault response on the ALS2 simulator arrives on site with a verifiable track record, not just a certificate. That changes the conversation between training providers, employers and regulators, and brings operator readiness into line with standards already expected in sectors such as petrochemicals and water treatment.

Inside the simulator environment

The simulator is built around a high-fidelity dynamic model of the ALS2 flow sheet, calibrated against pilot data gathered during the project's earlier phases. Control room graphics mirror the human-machine interface operators will eventually use, from the trend screens on the leach train to the alarm summary panel on the electrowinning section. Behind the graphics, a process model calculates mass balances, residence times and recovery yields in real time, so every keystroke has a believable consequence further downstream.

Instructors have a separate console that lets them introduce a fault, hold the simulation at a chosen moment, or replay a critical segment for discussion. Common training scenarios include a slow drift in the oxidation-reduction potential probe, a sudden drop in feed solids concentration when an upstream shredder surges, and a thermal excursion in the precipitation tank during a shift change. Each scenario is accompanied by a checklist of expected operator responses, drawn directly from the standard operating procedures used on the real plant.

The visual environment is deliberately understated. Rather than gamifying the experience with flashy graphics, the design team chose a clean, instrument-panel aesthetic that resembles the actual control desks installed at ALS2 reference sites. That decision was influenced by feedback from operators in Adelaide and Perth who took part in early usability trials and pointed out that anything too game-like would feel out of place in a process environment. The result is a tool that trainees respect because it looks and behaves like the real thing.

Building operator competency beyond the screen

A simulator only delivers value when woven into a broader training plan. The ALS2 project partners designed it to be paired with classroom sessions on hydrometallurgy, e-waste characterisation and environmental compliance, so operators understand what to do at the console and why each action matters. In Australia, that pairing has natural allies in the Certificate III and IV qualifications offered through TAFE and registered training organisations, which already cover many of the underlying process skills.

Assessment on the simulator is structured around observable competencies. An instructor watches how a trainee prioritises alarms, communicates with the shift supervisor during a disturbance, and documents each intervention in the batch log. Trainees are then marked against a rubric mirroring the European Qualifications Framework levels used elsewhere in the Horizon 2020 consortium, making it easier for Australian employers to translate simulator evidence into local recognition.

There is also a soft skill dimension that the simulator reveals during debrief sessions. Trainees who freeze during a fault, or click through alarms without reading the context, show patterns hard to spot in a normal classroom. Senior instructors can use that data to coach individuals on situational awareness, decision-making under pressure and structured handover routines, all of which are highly transferable to other process plants, including the lithium and rare earth operations expanding across Western Australia.

From simulator to site commissioning

The transition from simulated to real operations is where many training programmes lose momentum, and the ALS2 team has worked hard to avoid that gap. Simulator scenarios follow the same sequence of commissioning milestones operators will encounter on site, from the first water-only run-through to the introduction of feed material and the eventual ramp to design throughput. Trainees can step through each milestone on screen before they see it in steel and concrete.

This sequencing has practical benefits for Australian sites that may install ALS2 units alongside existing infrastructure. Where an operator is moving from a traditional smelter or a pyrometallurgical line to the acidless separation process, the simulator lets them rehearse the change of mental model without putting either the new or the legacy equipment at risk. The same operator can practise the startup sequence in the morning and return to their usual smelter duties in the afternoon, with training logged against a separate record.

For sites planning a brownfield installation, the logistics of integrating ALS2 into an existing smelting facility resource offers a complementary view of how the physical hand-off between simulation and commissioning actually plays out.

Comparing operator training approaches

Different approaches to training control room operators produce different results, and a side-by-side view below shows how the ALS2 simulator compares with the more familiar alternatives used across the Australian process sector.

Training approach	Realism of process response	Risk to plant and personnel	Repeatability of fault scenarios	Cost per trainee hour	Suitability for competency evidence
ALS2 training simulator	High, based on calibrated dynamic model	None, fully virtual	Unlimited, instructor-driven	Low	Strong, mapped to competency units
On-the-job mentoring on live plant	Very high	Elevated, especially during faults	Limited by production schedule	High	Variable, depends on assessor
Classroom and paper-based study	Low for fault response	None	None, static materials	Low	Moderate, theory only
Generic process simulator from third party	Moderate, generic chemistry	None	Moderate, limited library of faults	Moderate	Weak, not plant-specific
Augmented reality overlay on equipment	Moderate, depends on hardware	Low	Good, but hardware-bound	Moderate to high	Emerging, limited assessment frameworks

The simulator does not replace these approaches outright, but offers a bridge between classroom theory and live plant experience. For organisations that already invest in mentoring, it adds a safe environment for the messy first attempts at fault response. For those that lean heavily on classroom delivery, it gives a sharper edge to the practical component of any qualification.

The ALS2 consortium is inviting training providers, plant owners and vocational education bodies across Australia and the wider Indo-Pacific to explore how the simulator can be deployed alongside new plant installations or retrofit projects. Early adopters will shape scenario libraries, contribute local e-waste characterisation data, and take part in instructor certification workshops over the coming months. Reach out through the ALS2 project channels to discuss pilot programmes, licensing terms and integration with existing competency pathways, and bring the next generation of precious-metals recovery operators into the workforce.