GE says the ZLD system can treat up to 1600 gallons of water per minute “utilizing a combination of ultrafiltration, reverse osmosis, brine evaporation and salt crystallization technologies”

The process leaves behind only dissolved minerals – mostly salt – in the mine water, which are left behind in a crystalline form.

“The result is a unique solution that hits the mark operationally, environmentally and economically,” GE’s water and process technologies president Steve Watzeck said.

The Buchanan set-up makes use of GE’s ZeeWeed ultrafiltration technology, using hollow-fiber membranes to separate particles from the water, while reverse osmosis removes dissolved impurities through a semipermeable membrane.

“The concentrated brine from these elements of the system is then treated by GE’s proprietary thermal evaporation, crystallization and drying ZLD technologies, which make up the heart of this integrated process,” GE said.

The new set-up is expected to reduce the volume of mine water to be managed and also reduce freshwater demand as the processed water can be reused at the preparation plant.

The water treatment system is part of an overall infrastructure upgrade at the mine to be completed by the December quarter, a positive sign after Buchanan was idled from March to mid-July last year due to tougher coal markets.

With commissioning started, Buchanan will be the first American coal mine to use GE’s ZLD water treatment system.