WA’s First Lithium Plant Boosts Green Credentials with New Off-Take Deals for By-Products
Western Australia’s first lithium processing plant is making major progress in establishing its global green credentials by securing off-take agreements for its non-lithium materials, produced in the refining of locally mined and beneficiated hard rock lithium spodumene.
Tianqi Lithium Energy Australia (TLEA) owns the Kwinana lithium hydroxide plant in a joint venture between global new energy materials company Tianqi lithium Corporation, China, dual listed on the Shenzhen and Hong Kong Stock Exchange, and ASX- listed mining and exploration company, IGO Ltd.
The plant achieved first battery grade product in May 2022 and began exporting to customers in Korea and Europe this year.
While this is a significant milestone for WA’s downstream processing industry, lithium and other critical minerals required for the energy transition must be produced with a carbon-neutral balance by 2050 to achieve global decarbonisation targets.
A key factor for lithium in achieving this goal is finding beneficial uses for the byproducts that result from the refining process.
TLEA Chief Executive Officer Raj Surendran said the refining process at its Kwinana plant resulted in more than 10 tonnes of byproducts, the most significant of which is aluminosilicate, at a ratio of seven tonnes to one tonne of lithium hydroxide. TLEA’s aluminosilicate is called TAS (Tianqi Aluminosilicate). Its technical term is Delithiated Beta Spodumene (DBS).
The plant also produces gyplime and sodium sulphate as additional by-products.
“Without beneficial uses, these products would end up in landfill at a cost of between $250 and $300 a tonne,” Surendran said. “This is neither financially nor environmentally sustainable.”
Lithium-bearing spodumene from the Talison Lithium Mine at Greenbushes, recognised as the largest, highest quality and lowest cost hard rock lithium mine in the world, is the sole feedstock for the Kwinana plant. Greenbushes is owned by TLEA (51 per cent) in a joint venture with US company Albemarle, one of the world’s largest lithium producers. Albemarle also uses Greenbushes feedstock at its Kemerton plant.
Greenbushes produces spodumene at a grade of six percent lithium oxide, the quality required to meet the very specific purity requirements of battery grade lithium hydroxide.
Since 2016 when Tianqi Lithium Corporation began construction of the processing facility, the company has invested more than $13 million in developing beneficial, and potential commercial uses for its byproducts.
“Sodium sulphate is a key ingredient in detergent and washing powder,” Surendran said. “Unfortunately, there is currently no local market for sodium sulphate, but we have secured an offtake agreement with a customer overseas, to receive all our sodium sulphate, at current levels and when we reach nameplate capacity.
“Aluminosilicate has pozzolanic properties which means it has potential as a binder in cement products. For several years now, we have been working with researchers and industry on various uses for aluminosilicate, and our TAS in particular, as a partial replacement for cement.
“Cement is one of the most used man-made materials in the world, but it can’t be produced without creating process emissions. According to CSIRO, if the global cement industry were a country, it would be the fourth-largest national carbon emitter in the world.
“Western Australian cement manufacturers currently import slag from Asia to add to cement to reduce the embodied CO2 and Scope 3 emissions in their product.
“As a domestically available pozzolan, using TAS as a partial replacement for cement would avoid carbon miles, and further reduce embodied CO2 and Scope 3 emissions.
“Each tonne of TAS used instead of cement will save almost one tonne of carbon emissions, and approximately 100kg when used to replace fly ash.”
Surendran said TLEA’s refining process for lithium hydroxide optimised the use of its aluminosilicate as a partial cement replacement because it did not contain gyplime, which reduced its sulphate content.
“This process is unique in Australia with the Kwinana plant specifically designed to separate the aluminosilicate and gyplime,” he said.
“One train at our Kwinana plant will produce 170,000 tonnes of TAS – so there is a potential to remove 170,000 tonnes of emissions each year, from each production train if used to directly replace cement.”
For TAS and other manufactured pozzolans to be accepted in Australia for use in cement, changes are required to the Australian standard, AS3972:2010 General purpose and blended cements.
TLEA, in collaboration with cement manufacturers and other industry representatives, has formed the Australasian Pozzolan Association (APozA) and developed a new Australian Standard AS3582.4:2022 Supplementary cementitious materials, Part 4: Pozzolans — Manufactured. This standard recognises the use of TAS as a supplementary cementitious material in concrete, mortar and other related applications.
APozA is now leading the initiative to update ordinate and subordinate standards to directly specify the use of TAS/DBS as an ingredient for use in blended cement and concrete, which is typically used in a broad range of construction applications. AS3972 would allow it to be included as part of the mixture formulation and a recognised replacement for cement powder and/or fly ash.
Surendran said negotiations were also underway with customers in the agricultural industry to use its gyplime as a soil ameliorant.
“Our R&D team has been undertaking trials in WA’s Great Southern region to test our gyplime as a soil conditioner for agricultural crops, including canola and wheat,” he said.
“If these trials prove successful, it could open the door for gyplime to be widely adopted in commercial agriculture.”
