The company has moved quickly by approving the front-end engineering and design (FEED) process and is procuring long-lead equipment.
It aims to reduce the time frame through to commissioning and production, which is scheduled for early 2021.
The SiLeach® hydrometallurgical process is used to extract and recover lithium values from lithium bearing materials.
Lithium Australia expects to complete agreements this quarter resulting in supply of the plant site; infrastructure including power, water, gas, road and rail; major reagent supplies; and process feed material.
Adrian Griffin, managing director, said: “Our commitment to advancing the process to an industrial scale is a critical element in the research and development required to bring a superior process into the lithium industry.
“Success will allow us to utilise mine waste in the production of lithium chemicals, one of our great sustainability goals.”
Waste streams a source of lithium
Large quantities of lithium continue to be discharged to waste streams emanating from the production of a range of industrial minerals.
Such waste streams, which most commonly contain lithium micas, may prove the most cost-effective source of primary lithium.
The development of more efficient processing technologies to allow exploitation of such materials is a major corporate achievement of Lithium Australia.
In July 2017, Lithium Australia completed a preliminary feasibility study on the application of its SiLeach® technology to the recovery of lithium chemicals from micas.
Water balance a critical area
The study identified the water balance as a critical area for consideration.
Innovative process steps have subsequently been developed to improve the water balance, which have also reduced capital costs.
Processes have also been developed that capitalise on co-production of potassium sulphate, a critical step in achieving optimum financial performance.
This increased confidence led to the company’s decision to build a large-scale pilot plant.
Annual rate of 2,500 tonnes
The plant is designed to produce lithium carbonate equivalent at an annual rate of 2,500 tonnes from circa 27,500 tonnes of lepidolite mica feed.
Pilot plant output is around one-tenth the scale of output of a full-scale commercial production facility.
Target feed material during the first 12 months of the plant's operation will be primary ore mined close to the proposed location of the plant.
Crushing, grinding and concentration circuits will therefore be required at the feed end of the plant.
Lithium Australia has been involved in research and development of chemical processing technology for the economic recovery of lithium from spodumene and lepidolite minerals since 2014.
This led to the development of the SiLeach® process, a fluoride-accelerated sulphuric-acid leach at elevated temperature but atmospheric pressure.
Constructing and operating the pilot plant is considered a necessary step in the commercialisation of SiLeach®, in that it will integrate data collected on an industrial scale to evaluate the next step, which is full commercial production.