TEST results last month have confirmed early Sulphate of Potash (SoP) targets for prospective Western Australian fertiliser manufacturer and exporter Salt Lake Potash.
Salt Lake Potash (SO4 on Australian Securities Exchange listings) is the front runner out of about six WA companies looking to produce and export SoP fertiliser from hypersaline brine collected or pumped from remote salt lakes.
It is planning to produce its first commercial premium grade powder SoP fertiliser in the first quarter next year, followed by a fertigation grade soluble SoP product, at its Lake Way project, 25 kilometres south of Wiluna.
In March, SO4 harvested a 277 kilogram bulk sample of harvest salts from a single cell in its 125 hectare stage one evaporation pond network at Lake Way to confirm process plant feed grades and to produce samples of SoP fertiliser for potential customers.
The brine feed into the ponds came from both a network of channels on the salt lake surface and pumped from the Williamson pit of a former gold mine on the lake, SO4 advised the securities exchange last Friday in a report on the test results.
As previously reported in Farm Weekly, SO4 fast tracked its SoP fertiliser project by transferring it from Lake Wells, north east of Laverton, to Lake Way and using hypersaline brine pumped from the flooded Williamson pit as initial feedstock for its evaporation ponds.
The kainite and schoenite harvest salts were dried and homogenised and a representative 0.25kg sample was sent to the Bureau Veritas laboratory in Perth for chemical analysis.
The same laboratory produced SoP samples in early 2019 from harvest salts produced by Australian Potash at its Lake Wells project and used in on-going field and greenhouse fertiliser trials in WA.
SO4 said the sample analysis confirmed a potassium content of 7.5 per cent which was within the range of "expected outcomes" and was above the average feed grade of 6.8pc used in the bankable feasibility study for the project.
Sulphate concentration of 20.9pc also matched expectations and sodium (24.4pc) and magnesium (3.3pc) levels aligned with the anticipated plant feed grade, it said.
The remainder of the bulk sample of harvest salts is being shipped to Saskatchewan Research Council (SRC) in Saskatoon, Canada, for further confirmation testing and to produce more SoP samples to provide to companies with off-take agreements for SO4's fertiliser.
An acknowledged world authority on SoP, the SRC did the initial sample test work in 2018 and 2019 for SO4 to enable it to model likely results.
Commissioning of stage one of SO4's evaporation ponds began in May last year so they have been operating for 12 months with a continuous inflow of brine.
At the end of April, 2.7 gigalitres of brine has been pumped into the pond network, SO4 said.
SO4 chief executive officer Tony Swiericzuk said the "positive" test results confirmed the ponds were operating within design parameters and producing high grade potassium feed salts which can be converted to premium quality SoP fertiliser.
"Following the strong results from pumping our first brine abstraction bore reported last week, today's results further highlights the extent to which the Lake Way project and our on-lake production process has been de-risked over the past 12 months," Mr Swiericzuk said on Friday.
Shares in former SoP fertiliser front runner Kalium Lakes Ltd (KLL) were due to return to trading this week, having been voluntarily suspended from February 21 while the company reorganised to raise $61 million to cover a shortfall in funds estimated to complete the construction phase of its Beyondie SoP fertiliser project, 160 kilometres south east of Newman.
KLL this week advised the securities exchange it had successfully completed the new share issue and five-for-seven pro-rata entitlement issue of new shares to institutional investors as the first part of its fund raising.
Similar new share and entitlement share issues to ordinary shareholders are expected to be completed this month to raise the remainder of the funds.
KLL proposes to start commercial production and export of a premium SoP fertiliser in the third quarter next year.