Chemical aspects of coal washing

The present work is concerned with the examination of some chemical aspects encountered in coal preparation plants on the Illawarra escarpment of N.S.W» These chemical pariuneters can be cleuasified into three broad groups: firstly, relationship between natural water quality associated with coal washing and efficiency of the washing process. This essentially Icc2 was a continuation of a survey began in 1972 and a monthly monitoring programme looking at total hardness, chloride, calciiim, pH, bicarbonate €Lnd carbonate concentrations as well as temperature was carried out. It was found that mine drainage water in one mine in particular contained large amounts of calcium and was in fact supersaturated with respect to calcium carbonate. Secondly, an observation of meteorological factors affecting water quality was commenced but had to be curtailed due to unusual weather conditions prevailing. Thus the second aspect was a chemical and mineralogical analysis versus particle size of coal tailings. The major constituents were found to be coal, clay, qxiartz and carbonates together with smaller amounts of other minerals.