A DIRECT DETERMINATION OF ORGANIC AND INORGANIC SULFUR IN COAL BY CONTROLLED OXIDATION

DILUTED COAL SAMPLES SUBJECTED SIMULTANEOUSLY TO AN OXYGEN TREATMENT AND A LINEAR INCREASE IN TEMPERATURE EVOLVE SULFURDIOXIDE (SO2) INTERMITTENTLY AS A FUNCTION OF TEMPERATURE. DISTINCTIVE SO2 EVOLUTION PATTERNS ARE OBSERVED AMONG COALS OF DIFFERENT RANK AND BETWEEN RAW AND TREATED COALS. THE GOAL OF PHASE I IS TO OBTAIN RESOLVED SO2 EVOLUTION PATTERNSFROM COALS ANALYZED BY THIS THERMAL OXIDATIVE DEGRADATION ROUTE. SOME QUALITATIVE AND QUANTITATIVE STUDIES HAVE BEEN COMPLETED AND ASSIGNMENTS MADE RELATING EACH SPECIFIC SO2 EVOLUTION TO THE TYPE OF SULFUR PRESENT IN COAL. THE SO2 EVOLUTION PATTERNS RESULTING FORM PYRITIC SULFUR AND AROMATIC ORGANIC SULFUR IN COAL ARE NOT COMPLETELY RESOLVED. THESE EXPERIMENTS ARE DIRECTED AT RESOLVING THESESO2 EVOLUTION PATTERNS. A MORE SENSITIVE GAS DETECTION SYSTEM WILL BE USED WITH AN EXISTING THERMAL OXIDATIVE DEGRADATION SYSTEM. THIS ENHANCED SENSITIVITY WILL PERMIT SMALLER COAL SAMPLES TO BE ANALYZED, THUS MINIMIZING ANY EXOTHERMS. THE RESOLUTION OF SO2 EVOLUTION PATTERNS RESULTING FROM THERMAL OXIDATIVE DEGRADATION OF COAL WILL BEOPTIMIZED AS A FUNCTION OF SAMPLE SIZE, HEATING RATE, OXIDANT CONCENTRATION, AND FLOW RATE. THIS RESEARCH COULD PRODUCE TWO SIGNIFICANT RESULTS: A METHOD FOR PREDICTING THEBENEFICIATION POTENTIAL OF COALS; AND A ONE-STEP PROCEDURE FOR CHARACTERIZING THE INORGANIC, ORGANIC, AND TOTAL SULFUR PRESENT IN COALS AND CLEAN COALS.