Study of importance of coal fines processing and applicability of different processing routes for improving process efficiency

Abstract

National Steel Policy 2017 envisages crude steel capacity to grow upto 300MTPA by 2030-31 and coal, being one of the major requirements, will play an important role in achieving the target. There are a few substitutes e.g. Biomass, Charcoal etc., which can be used in place of coal but none of them can replace coal entirely as of now. The reserves comprising of good quality coal are fast depleting. Hence, processing of low grade coal and effective usage of coal preparation plants (CPP) disposed tailings are of grave importance. Processing of coal fines are carried out by different beneficiation routes mainly froth flotation, autogenous cyclones etc. Liberation size is decreasing drastically and existing methods are inefficient to fully recover the fines. Applicability of two processes - selective flocculation and liquid-solid fluidization - on processing of coal fines of Eastern India have been attempted in this work. Different coal samples and size fractions have been taken to test the feasibility of the said beneficiation routes. While liquid-solid fluidization gave better results at relatively coarser sizes, results were good at finer sizes in selective flocculation of coal fines. Effect of operational parameters on the combustible recovery of coal fines and the process efficiency have been investigated.