Beyondie sulphate of potash (SOP) project is a high-grade brine deposit being developed by Kalium Lakes (KLL) in Western Australia.
Pre-feasibility study (PFS) of the two-phased Beyondie SOP project was completed in 2017, followed by the bankable feasibility study (BFS) in September 2018. Early construction works of the underground project are expected to commence in the third quarter of 2018, with production scheduled to commence in 2020.
The project is expected to produce at a rate of 164,000 tonne per annum (tpa) of SOP over a mine life of more than 30 years. It is expected to produce premium granular and soluble suite of products containing more than 51% K2O and less than 0.5% Chloride.
Beyondie sulphate of potash project location, geology and mineralisation
The Beyondie project is located to the east of the Great Northern Highway in Western Australia and extends into the Little Sandy Desert.
Spread over approximately 2,400km² (240,000ha) of granted mining tenure, the site is located 160km south, southeast of the iron ore producing town of Newman and 200km north of the base metals and gold mining areas of Wiluna.
The deposit has brine-containing potassium and sulphate ions, which can form a potassium sulphate salt. Most of the brine is located within the saturated sediments below a lake surface and in sediments adjacent to the lake.
Brine grade of the project is one of the best in Australia, while the sodium to potassium (Na:K) ratio of 9.4:1 is far superior to its competitors.
The deposit is hosted in the Collier, Salvation, Scorpion, and North-West Officer basins, and the Marymia Dome located on the northeast fringe of the Yilgarn Craton. It comprises Archaean greenstone belts intruded by granites, prominently monzogranitic rocks, which outcrop to the south of the project.
Beyondie sulphate of potash project reserves
The Beyondie sulphate of potash project is estimated to contain proven reserves of 1.65 million tonnes (Mt) grading 13,830mg/l SOP, and probable reserves of 3.49Mt grading 11,820mg/l SOP.
Mining at Beyondie
KLL proposes to use submersible bore pumps to recover brine from the deeper aquifer, while shallow trenches will be used at the surficial aquifer. The production bores will also capture any leakage from brine-bearing segments within the palaeovalley clay and fractured/weathered bedrock.
Solid raw materials will undergo brine concentration and crystallisation process at the processing plant, wherein water will be removed through solar evaporation in the evaporation ponds. It results in the sequential crystallisation of gypsum, halite, and astrakainite in the first two sets of ponds.
Calcium and sodium salts will be left within the ponds, while the remaining brine crystallises in the next set of ponds to produce Kainite type mixed salt (KTMS) consisting of leonitic, schoenitic and carnallitic mixed salts. The resultant salts will be harvested and stored separately prior to mixing, pre-crushing and transferring to the SOP plant.
The product will be forwarded to the purification plant, which will store and crush the potash salts and convert them to raw schoenite by applying cooled SOP mother liquor.
After conversion, the schoenite will crystallise separately from halite, allowing for the separation of the salts from each other, followed by flotation of schoenite. The flotation process will reduce the concentration of halite in potassium-bearing salts to approximately 10% of its original concentration. Separation of flotation liquor and primary schoenite is performed by centrifuges.
The secondary schoenite will undergo cooling crystallisation by mixing with warm aqueous SOP solution in a loop reactor at approximately 48°C. SOP will be subject to centrifuge before purifying further by washing with aqueous SOP liquor. The resulting liquid will be recycled to the schoenite decomposition step.
The wet, purified SOP will be dried by using a fluidised bed dryer, compacted in a hammer mill and packed into bags/stored as a bulk product.
Off-take of products from the Beyondie SOP project
KLL has entered terms sheet with K+S, a fertiliser producer and distributor based in Germany, for the sale of 100% of phase one production from the project.
KLL entered a non-binding off-take Memorandum of Understanding (MoU) with WITTRACO Düngmittel in June 2017, for the sale of 20% annual SOP from the Beyondie project during the first five years of production.
Infrastructure at Beyondie project
Access to the project site is through the Great Northern Highway (GNH), located north of the existing Kumarina roadhouse. The final product is also proposed to be hauled by road via the public road network.
A centralised gas-fuelled power station located near the processing plant will provide electricity required for the operations.
Raw water will be collected from water supply bores located 16.09km south of Kumarina, through pipes.
K-UTEC AG Salt Technologies (K-UTEC), a company based in Germany, compiled the technical report and bankable feasibility study (BFS) of the Beyondie project.
DRA Global, Advisian, Shawmac, Wyntak, and Preston Consulting served as principal technical consultants for the study. RSM, DLA Piper Australia, HopgoodGanim Lawyers and BurnVoir Corporate Finance were engaged as accounting, legal, commercial and financial advisors.
K-UTEC also conducted test work and engineering studies for verifying the evaporation pond and purification process design. It also produced approximately 250kg of SOP, by using materials harvested from the solar ponds from evaporation programme, as part of the pilot plant works.
The Saskatchewan Research Council (SRC) was engaged for confirming and verifying the potassium sulphate recovery process, while Sahut-Conreur and Köppern were engaged to conduct test work for drying and compaction/agglomeration.