Tóm tắt:

The contaminated waste is a by-product generated during coal mining process. This type of waste may contain about 20% of clean coal and its ash content may vary in a wide range of 60% to 75%. The waste is normally stockpiled separately at “temporary disposal dumps”. This waste is not regarded as a waste but it is very costly to process. A large quantity of representative samples from Coc Sau waste disposal dump have been collected and a number of experiments for clean coal recovery have been carried out using a combination of low cost and highly efficient semi-industrial movable screen jig, fluidized bed separator and flotation machine. From this waste, the obtained clean coals of the separation processes have met the Vietnam quality standards requirements (suitable for trading) and the tailings have ash content of over 80%. The study results showed that the application of these new machines could allow significant recovery of clean coal from contaminated wastes. This may significantly contribute to the reduction of environmental pollution while ensuring the production viability and economic efficiency for the miners.