Impact Minerals (ASX:IPT) has finished the June quarter with a healthy bank balance as it checks the boxes towards completion of a Pre-Feasibility Study for the Lake Hope High-Purity Alumina (HPA) Project in Western Australia.
The junior explorer, which has a market capitalisation of $45.9 million, has $3.4 million cash on hand following a placement, the exercise of listed options and a research and development rebate.
Impact is advancing a PFS for Lake Hope, which is on track for completion in the final quarter of this year.
As part of that, Impact is investigating the potential carbon dioxide (CO2) emissions from the project with the aim of making Lake Hope completely carbon neutral over time.
Impact says a preliminary study completed in the June quarter showed that scope one and scope two CO2 emissions would likely be “significantly lower” than incumbent processes that produce HPA, and on par with or even much lower than emerging processes.
Scope one emissions generally relate to CO2 produced directly from operations and include the proposed mine, haulage of ore, and the processing plant.
Scope 2 emissions relate mostly to CO2 produced from the energy used to power the company’s operations.
For Impact to achieve its net zero carbon goal, it needs to eliminate or offset the emissions from power generation as well as from mining, transport, and calcining.
Calcining, heating in a furnace, is the final stage of the HPA process.
The majority of emissions can be slashed by using 100% renewable energy.
The South West Interconnected System, which is Western Australia’s main power source, currently generates coal-fired power, though the state government is planning to transition the network to entirely renewables by 2030.
Using the current Western Australian electricity supply, likely emissions are 4.38 tonnes of CO2 per tonne of HPA produced via the sulphate process, and 3.44 tonnes of CO2 per tonne of HPA for the low-temperature leach (LTL) process.
Impact can eliminate most of the emissions linked to power generation by either build-out or contract-to-purchase a renewable energy supply.
Advances in renewables technology also offer the potential to power the Lake Hope process plant entirely by renewable energy.
This has allowed the company to model the CO2 emissions based on a 100% renewable energy scenario, which shows a reduction of 1.35 tonnes of CO2 per tonne of HPA.
The lowest known CO2 emissions of HPA production is achieved through hydroelectric power, and Impact says its HPA production would be on par with or better than that if it uses entirely renewable energy.
Mining and transport emissions, which are relatively small, will require the deployment of low-carbon fuels, or hydrogen-powered or electric vehicles for mining equipment and long-distance haulage.
Calcination, meanwhile, is very energy intensive and a significant contributor to scope one emissions.
The technology is a key focus of global decarbonisation research and development, with several technologies in the testing phase, including microwave heating, electric arc calcination and other opportunities.
Impact says it will seek to understand the capacity and limitations of nascent calcine technologies for Lake Hope, and monitor the maturing technologies in the medium term.
“Impact will strive to reach full decarbonisation of the project over time,” the company says.
“Impact will continue to develop its understanding of the prospective emissions of the Lake Hope Project and the technical barriers to achieving net-zero carbon HPA at Lake Hope.”
The company is continuing metallurgical testwork for both the sulphate and LTL processes, while also progressing talks with Ngadju Aboriginal group to support a mining lease application, and assessing drill results from neighbouring lakes.
HPA is on the Australian Government’s critical mineral list and is used in the manufacture of lithium-ion batteries, LED lighting, semiconductors and sapphire glass.
Lake Hope has an existing resource of 3.5 million tonnes @ 25.1% for 880,000 tonnes of contained alumina, which would be processed into HPA.
Earlier this year, Impact demonstrated it could produce HPA of over 99.99% (4N) using the patented Playa One Sulphate Process.
Preliminary talks with potential customers indicate very strong demand for 4N HPA, according to Impact. The product, which is used to coat the separator between the anode and the cathode in a lithium ion battery, can fetch between US$15,000 ($22,744) and US$25,000 ($37,907) per tonne.
During the June quarter, the company ticked off three key milestones towards the completion of the PFS, which were making key appointments to the PFS team, and receiving the results of baseline flora and fauna surveys and the CO2 emissions study.
The baseline flora and fauna surveys indicate there is no threatened or priority species in and around the salt lakes that host the alumina-bearing mud at Lake Hope.
Write to Angela East at Mining.com.au
Images: Impact Minerals
