Processing Plant

The processing plant has a rated raw coal feed capacity of approximately 600 tonnes per hour. Heavy media cyclones are used for coarse raw coal cleaning and flotation is used for fine raw coal cleaning to produce clean coal products.

Run-of-mine (ROM) coal is delivered by truck to an existing ROM coal stockpile. ROM coal is reclaimed using vibratory feeders, located in a reclaim tunnel. The feeders load the ROM coal onto a reclaim conveyor that transfers the coal into the breaker station. Initial coal processing is conducted through the rotary breaker where the coal is sized to minus 38 millimeters. Oversize material, mainly rock, is conveyed to an open, on-ground storage pile and then trucked to the existing coarse reject disposal facility. After the removal of the oversize material in the breaker, the plant feed is conveyed to the 1,800-tonne raw coal silo. Raw coal is recovered from the silo by four vibratory feeders onto the coal processing plant feed conveyor, which is equipped with a tramp iron magnet and a belt scale, and conveyed to the desliming section of the processing plant.

The raw coal feed is divided and distributed over eight sieve bends that discharge directly to eight desliming screens. The deslimed coarse coal then passes to a mixing box where it is mixed with water and magnetite and fed to eight 600 millimeter diameter heavy media cyclones. The fine coal screen underflow is pumped to a distribution box and then pumped to the froth flotation circuit.

The raw coarse coal is separated into clean coal and rejects in the heavy media cyclones. The magnetite media is recovered from each product on drain and rinse screens. The drained coarse clean coal is dewatered in centrifuges and discharged to the clean coal conveyor. The drained coarse reject material is conveyed to the discard bin for removal by truck to the disposal facility.

The fine raw coal is separated into clean coal and fine refuse in a bank of five 8.5 cubic metre capacity flotation cells. Reagents are required for this flotation process. The clean coal froth is passed to vacuum disc filters for dewatering. The filter cake is then discharged from the disc filters and combined with the clean coarse coal on the clean coal conveyor for transport to the thermal dryer, where the coal is currently dried during winter months. The thermal dryer is located in a separate building adjoining the coal processing plant and fuelled with natural gas.

Dried clean coal from the dryer is then conveyed to the clean coal stockpile. The fine coal refuse from the flotation cells is thickened in a thickener circuit and pumped to the refuse ponds located on the south side of the Smoky River.

Clean coal is reclaimed using flat back feeders, and then transferred by conveyor to a load-out bin for loading into rail cars. After loading, the top surface of the coal is sprayed with a latex solution to inhibit dusting and coal losses during rail transport