Air sparged hydrocyclone for fine coal flotation

The cleaning of fine coal to achieve compliance specifications generally is a challenging problem for coal preparation engineers. Gravity separation techniques are limited with regard to capacity/ efficiency considerations, and the most promising process alternative seems to be flotation, the use of which in the U.S. has grown significantly from an installed plant capacity of 47,000 tpd in 1965 to a plant capacity of 64,000 tpd in 1975 and a capacity of 145,100 tpd in 1985.