A Study on the Size Analysis and Size Degradation of Jharia Coals (Part II)

The washeries proposed to be installed in the coking coal sector are being designed to treat crushed run-of-mine coals including the slack. The proportion of slack, as contained in coals, raised from individual mines and/or seams shows wide variations being chiefly influenced by their geological formations, method of mining and nature of explosives used in mining operations, which have been indicated and discussed here. But, in addition to these common causes, which lead to the production of natural slackm there are other factors which can add to the amount of slack considerably before these coals reach the washery end and more so when they are crushed, stored and subsequently handled before feeding to the washery proper. As a correct estimate of the proportion of slack, which is to actually enter the washing units, is of paramount importance from the point of view of supplying balanced feed to the washery and ensuring its smoother operation, an attempt has been made in this paper to analyse the effects of each of these factors with respect to different coals of Jharia coalfield