METHOD OF FABRICATING BROWN COAL BRIQUETTES Russian patent published in 2001 - IPC

FIELD: solid fuels. SUBSTANCE: brown coal is subjected to electrochemical treatment in sodium chloride aqueous solution to form coal-humate mixture, which is then partially dried and briquetted at 85-95 C. Humates are converted into humic acids when treating coal-humate mixture with hydrochloric acid to pH 4.0-4.5. Compressive strength of briquettes is thus increased by 10.6-21.8%. Method is applicable in mining and coal-processing industries. EFFECT: increased mechanical strength of briquettes. 1 tbl