Trigg Minerals has reported positive initial results from testing of a new sulphate of potash (SOP) processing technology to produce potassium-rich feed salts from its flagship Lake Throssell project in Western Australia.
In its latest quarterly report, the company said bench-scale testwork using the innovative new method had shown promise in obtaining high-quality feed salts more quickly and efficiently than conventional evaporation techniques.
The testwork is designed to provide an alternative to secondary evaporation ponds where the concentrated brine is maintained in an equilibrium to precipitate complex potassium-rich salts (kainite-type mixed salts, or KTMS).
Maintaining this part of the process in a steady-state when open to the atmosphere – with all of the consequent changes in temperature, pressure and humidity – has been reported as problematic for the industry’s early movers.
The new technology could deliver a more simple and commercially-robust method of processing feed salts and recover some of the water from the brine which would ordinarily be evaporated into the atmosphere.
Which could significantly de-risk the Lake Throssell project and have positive implications for the state’s broader SOP industry.
Pilot-scale test
Testing with increasing volumes returned consistent results during the June quarter and paved the way for a proposed pilot-scale test before year end.
It will involve a 2.4 cubic metre (or three tonne) sample of concentrated brine from Lake Throssell’s surficial aquifer, simulating harvest results following halite (sodium chloride or table salt) precipitation using solar evaporation.
Testing will provide an estimation of the potential water recovery from the brine and assess the water quality.
Trigg expects the pilot-scale test will provide sufficient data to establish a concept-level engineering design (including additional energy requirements) and quantify savings from improved process reliability and efficiency, pond reduction and acceleration of the ramp-up phase.
Effort paying off
Trigg managing director Keren Paterson said the effort put into research and development of alternative technologies was starting to pay off.
“We are beginning to generate some hard data to support our evaluation of what could well turn out to be a game-changer for Trigg and the broader SOP industry,” she said.
“We are at a pivotal moment in the development of this new technology which has the potential to improve the processing reliability of a much-needed and essential mineral fertiliser required for sustainable food production.”
Ms Paterson said fieldwork at Lake Throssell was currently on hold, except for maintenance of the weather station where Trigg is collecting essential baseline data for project design and approval purposes.
