A pilot-scale treatment of coal preparation plant effluent by the selective agglomeration process

CIM Bulletin, Vol. 72, No. 811, 1979

LW. ARMSTRONG, A.R. SWANSON and S.K. NICOL, BMP Central Research Laboratories, Shortland, Australia

The construction, commissioning and operation of a continuous pilot-scale selective agglomeration (oil agglomeration) unit are described. This plant has been used to recover fine coal from an effluent stream that is produced by a jig plant which scalps the coal from a New South Wales (Australia) colliery. The reject slurry is extremely fine (66.5% minus 53 pm) and has an ash content of approximately 40%. The pilot plant can treat up to 0.3 tonne/h of this slurry, producing average product ashes as low as 9.1% and tailings ashes greater than 80%. The average yield observed was 62%, which corresponded to a recovery of coal material of 88%. The operation of this pilot plant yielded data that enabled an economic assessment of this type of processing to be carried out.This study showed that selective agglomeration is an economically viable process for eliminating the substantial losses of coal to tailings ponds and minimizing consequent disposal and environmental problems. A commercial plant has been constructed and commissioned on the basis of the data obtained from this pilot-scale operation.
Keywords: Coal treatment, Effluents, Agglomeration, Selective agglomeration, Environmental control, Tailings.