IMPROVING THE PERFORMANCE OF CONVENTIONAL AND COLUMN FROTH FLOTATION CELLS

BECAUSE OF MORE STRINGENT SULFUR DIOXIDE EMISSION RESTRICTIONS IMPOSED UNDER THE 1990 CLEAN AIR ACT AMENDMENTS AND THE IMPORTANCE OF RAW COAL COST AND PROCESSING COST, MANY DOMESTIC MINING COMPANIES PRODUCING HIGHER SULFUR CONTENT COALS WILL BE FORCED OUT OF BUSINESS FOR QUALITY AND/OR ECONOMIC REASONS. THIS SITUATION MAY FORCE THE CLOSURE OF MARGINAL OPERATIONS THAT ARE VITAL TO MANY STATE ECONOMIES. HOWEVER, STUDIES INDICATE THAT MANY HIGHER SULFUR COALS MAY REMAIN ACCEPTABLE AS FEED STOCKS IF MORE EFFICIENT FINE COAL CLEANING TECHNOLOGIES CAN BE DEVELOPED OR CONVENTIONAL FINE COAL CLEANING TECHNOLOGIES CAN BE IMPROVED. BECAUSE OF THIS NEED AND SINCE MANY EXISTING COAL PROCESSING FACILITIES EMPLOY SOME TYPE OF CONVENTIONAL OR COLUMN FLOTATION CIRCUIT, IMPROVING THE EFFICIENCY OF THESE EXISTING TECHNOLOGIES WOULD PROVIDE THE GREATEST BENEFIT. THIS PROJECT WILL INVESTIGATE THE EFFECTS OF HIGH-SHEAR PRETREATMENT OF COAL FEED ON FROTH FLOTATION PERFORMANCE AND CHEMICAL REQUIREMENTS. THE PHASE I OBJECTIVE IS TO IMPROVE BTU RECOVERY AND INCREASE PYRITE REJECTION WHILE REDUCING CHEMICAL COSTS. THIS PRETREATMENT WILL ENHANCE COLLECTOR SELECTIVITY AND BETTER DISPERSE THE COLLECTOR TO MAKE THESE IMPROVEMENTS.