Talbot, a South African company specialising in water and wastewater treatment, is embarking on a new adventure. “A major coal producer in the Highveld recently asked us to provide a solution for the disposal of gypsum generated as a by-product of its coal mine water purification process,” says Claire Lipsett, Managing Director of Talbot Consulting Services.
Gypsum is a type of slurry generated from the treatment of wastewater from a coal mine. The mine is located in the Highveld, a high plateau in South Africa, where the greater Johannesburg metropolitan area is located. According to Claire Lipsett, the waste stream from the water treatment process flowing to a dam downstream of the mine contained a high content of gypsum, to the extent that the facility’s limited storage capacity was significantly reduced due to deposits at the bottom of its basin.
The gypsum treatment process
Prior to the validation of the mine operator’s offer in the Highveld, Talbot claims to have implemented a gypsum processing pilot project. The company, which employs 140 people, offers a solution for processing this mining waste in which a hydraulic filter press is used to dewater the gypsum, dry it and press it into briquettes to transport it “to end customers”.
“We have reduced solid waste from about 2,900 milligrams per litre (mg/l) to just 84 mg/l. We have also demonstrated that the technology can extract gypsum at a rate of 100 kilograms per hour at a large-scale mining site,” says Lipsett.
The two-week trial, explains the Managing Director of Talbot Consulting Services, demonstrated that effective solids removal could be achieved in a single step, without the use of flocculants (to facilitate decomposition, editor’s note) or coagulants, “and provided an appropriate and easy-to-use solution to achieve complete water management at the site”.
Jean Marie Takouleu