How simulation is filling nickel and cobalt’s data gaps and giving miners a credible way to prove environmental performance to global markets

When reliable environmental performance data doesn’t exist, simulation can step in – and according to IGO Nova’s Zachary Hearne, it could give Australian producers a market advantage.

Zachary “Zac” Hearne, manager – mine closure at IGO Nova Pty Ltd, has held a string of operational and technical roles across IGO’s portfolio. From metallurgist positions at Jaguar and Nova to leading technical services support on mergers and acquisitions, Zac has built a career at the sharp end of processing and project development.

Now completing a postgraduate research degree in nickel and cobalt processing funded by the Future Battery Industries CRC, Zac is applying that operational experience to a problem that cuts across the industry: how to quantify environmental performance when robust life-cycle data isn’t available.

At the AusIMM Critical Minerals Conference in Perth, his presentation walked delegates through a first principles-based approach to life-cycle analysis (LCA) of nickel and cobalt materials production. It was a session that resonated with mining professionals and practitioners facing growing demands for transparent, credible environmental reporting.

The data problem

LCA has become the international standard for assessing environmental impact across industries. It allows companies to quantify carbon footprints, compare processes, and benchmark performance. But as Zac explained, for emerging sectors like battery materials, the foundation data needed to conduct LCAs – known as life-cycle inventory (LCI) data – is often incomplete, inconsistent, or outdated.

“Much of the data available is generic or aggregated,” he said. “It doesn’t reflect the specifics of Australian operations, and where reliable data exists, it’s often hidden behind paywalls or bundled into international averages.”

For companies looking to demonstrate the sustainability of their supply chains to markets like the European Union, this creates a credibility gap. “Transparent and verifiable LCA data is now a prerequisite for market access,” Zac said. “If producers can’t provide it, they risk being excluded.”

Turning to simulation

The solution, Zac argued, is to build the missing datasets from first principles. His team developed detailed process models using METSIM software, applying mass and energy balance calculations to replicate four different nickel and cobalt production pathways:

• Nickel sulphide concentrate production, based on the IGO Nova flow sheet, covering underground mining, crushing, milling, and flotation.
• Nickel sulphate refining, using oxidative leaching and crystallisation to convert concentrate into battery-grade nickel sulphate hexahydrate.
• High-pressure acid leaching (HPAL) of laterite ores, producing mixed hydroxide precipitate (MHP).
• Battery recycling, simulating recovery of nickel, cobalt, and other metals from end-of-life lithium-ion batteries.

By generating material and energy flows for each step – from diesel use in mining to reagent consumption in refining – the models provided the detailed inputs and outputs needed to conduct LCAs.

“This approach gives us process-specific data where none previously existed,” Zac explained. “It’s transparent, reproducible, and tailored to Australian conditions.”

Scope 1, 2, and 3

One of the most striking insights from Zac’s modelling was how emissions break down across the three scopes defined in greenhouse gas accounting:

• Scope 1 (direct emissions) dominated in upstream operations such as concentrate production and HPAL, driven by diesel combustion, heavy fuel oil, and chemical reactions.
• Scope 2 (indirect emissions from purchased energy) was a relatively minor contributor in most pathways – with one exception. In nickel refining, the energy requirements of electrolysis and crystallisation made electricity supply a significant factor.
• Scope 3 (other indirect emissions) was the most significant category overall, particularly in refining. Transport of feedstock, transmission losses, and the production of reagents such as sulphuric acid and ammonia accounted for the bulk of total carbon impact.

“Understanding where the biggest contributions lie is essential,” Zac said. “It shows us where the opportunities are to reduce emissions – whether that’s switching to renewable power, optimising reagent use, or shortening supply chains.”

Comparing pathways

The modelling also allowed Zac’s team to compare the relative environmental performance of different production routes.

For example, the HPAL pathway, while effective in producing MHP, was associated with high direct emissions from acid production and limestone calcination. By contrast, recycling of battery feedstock showed promise but also revealed the complexity of recovering multiple metals from mixed chemistries.

“What the results demonstrate is that every pathway has hotspots – stages where emissions are concentrated,” Zac explained. “By identifying these, we can focus effort where it will make the most difference.”

Benchmarking against literature

Zac stressed that simulation-based LCAs are not a replacement for empirical data but a way of bridging the gap until more robust datasets become available.

His team compared their results against published LCA studies of nickel and cobalt production worldwide. While methodologies varied, the simulated results aligned reasonably well once differences such as sulphur-burning assumptions were accounted for.

“This gives us confidence that our approach is valid,” Zac said. “It provides a credible foundation for Australian producers to benchmark themselves against international peers.”

Implications for producers

For mining professionals and practitioners, the implications are clear. Reliable LCA data is becoming a licence to operate in global supply chains, particularly in the EU where regulatory reforms demand proof of environmental performance.

By using process simulation, producers can get ahead of the curve. “Even if you don’t have access to site-specific datasets, you can model your processes and generate transparent, verifiable numbers,” Zac said. “That gives you a stronger position in discussions with customers, regulators, and investors.”

He added that simulation also helps companies identify efficiency gains within their operations. “When you model every input and output, you see clearly where energy is being consumed, where emissions are generated, and where improvements could be made.”

Lessons for practitioners

Several practical lessons emerged from Zac’s presentation:

• Don’t wait for perfect data. Simulation can provide credible, transparent results that strengthen reporting now.
• Focus on material impacts. Scope 3 emissions from reagents and transport can outweigh scope 1 and 2 – and often receive less attention.
• Benchmark globally. Comparing results to international studies helps validate methodology and position Australian producers in the global conversation.
• Think strategically. Data generated for environmental reporting can also inform operational improvements, cost savings, and future project design.

Looking ahead

Zac acknowledged that more work is needed. His study covered selected pathways and focused primarily on global warming potential, with limited exploration of other impact categories such as acidification or water use.

“There’s enormous scope to expand this work,” he said. “We need more sensitivity analysis, more pathways modelled, and a broader range of impacts assessed. But this is a step towards building the transparent, process-specific datasets that our industry needs.”

Industry significance

For an industry under increasing scrutiny, Zac’s message was timely. Battery metals are essential to the energy transition, but their production comes with environmental costs. Proving those costs are being measured, managed, and reduced is now a commercial imperative.

Simulation-based LCA offers one way forward – providing the transparent, credible data that markets, regulators, and communities demand.

As Zac concluded, “Life-cycle assessment is about more than compliance. It’s about proving the value of Australian production, identifying opportunities for improvement, and securing a place in the global battery supply chain.”