A PROCESS FOR PRODUCTION OF LOW ASH CLEAN COAL WITH IMPROVED COKING PROPERTIES FROM LIGNITE COAL

摘要

The invention relates to a process for production of low-ash clean coal with improved coking properties from lignite coal, comprising; subjecting lignite coal lumps to pulverizing, washing and sieving to small particles of size from 0.5 mm or less to liberate dust particles; oven drying the coal particles for 5-6 hours at 105 o C; characterized by comprising the steps of ; adding aqueous alkali to the dried lignite coal to form a slurry with about 1-10 plup density; heating the slurry at a temperature of about 60 o C to extract humic substances; cooling the reactants and separating the extracted humic substances from coal by filtration; repeatedly washing the coal residue with distilled water; and separating the low ash coal by density separation at 1.4 specific gravity.