Environmentally friendly way to produce potash developed

A Canadian company claims to have developed an environmentally friendlier mechanism to produce potash, without generating salt tailings and requiring no surface brine ponds.

Gensource Potash, a Saskatoon-based firm, explains that the absence of tailings eliminates decommissioning risks, while not having ponds removes the single largest negative environmental impact of conventional potash mining.

The extraction method created by Gensource injects a hot salt (NaCl) brine into caverns to selectively dissolve potash (KCl). The subsequent NaCl/KCl brine collects in the caverns, to be collected and processed. KCl drops out through cooling crystallisation and the NaCl brine is reheated and re-circulated back to the cavern to repeat the process.

Meanwhile, the collected KCl solids are de-brined and dried out, before being compacted, sized and then loaded out.

Gensource says that its process has been carried out by a series of independent production facilities that are one-tenth the size of a traditional potash project, and that they can produce between 250,000-300,000 tonnes per year of the fertiliser.

Planned to be installed at the company’s Tugaske project, which is within the Vanguard Area in south-central Saskatchewan, the modules are said to use 75 percent less water per tonne of potash than conventional solution mining methods. They can also use brackish water sources, further reducing their freshwater usage.

Furthermore, the power at Tugaske is self-generated using natural gas rather than coal, which allows it to avoid up to 24,500 tonnes per year of CO2e of emissions.

The Rural Municipality of Huron, where the Tugaske project is located, recently granted it a development approval permit. However the Saskatchewan Ministry of Environment ruled in 2018 that the project should be considered ‘not a development’ because it doesn’t trigger environmental impact assessments due to its ‘green attributes’.

Once operations begin, Gensource Potash says it is committed to selling, for at least the next 10 years, 100 percent of the annual production from the Tugaske project to Helm Fertilisers, a US-based subsidiary of Helm AG, who will market it directly to customers using its own infrastructure.

However, at present, the fertiliser company is waiting on its senior lenders, KfW and Société Général to approve financing. The firm says that it is also wating to have project financing coverage approved through Euler Hermes, it concludes.