CHEMICAL COAL CLEANING AT LOW CAUSTIC/COAL RATIOS

COAL WILL BE CHEMICALLY CLEANED USING SODIUM HYDROXIDE AS CAUSTIC AT TEMPERATURES OF 350 TO 390 DEGREES CENTIGRADE, USING CAUSTIC/COAL RATIOS OF 2:1 AND LOWER. RECENT EXPERIENCE IN 10 LB/HR KILN RUNS HAS SHOWN THAT RATIOS IN THE RANGE OF 2:1 TO 1:1 MAY CAUSE A PASTY MASS TO FORM THAT STICKS TO THE REACTOR WALL PREVENTING GOOD HEAT TRANSFER FOR REACTANTS SUBSEQUENTLY PASSING THROUGH THE KILN. EXPERIMENTS WILL BE RUN TESTING THE VISCOSITY OF LOW CAUSTIC/COAL RATIOS AT SEVERAL TEMPERATURES TO DETERMINE IF A REGIME EXISTS THAT IS CHEMICALLY AND MECHANICALLY OPERABLEFOR CLEANING COAL. A LABORATORY-SCALE, STIRRED BATCH REACTOR WILL BE CONSTRUCTED FOR CONDUCTING TESTS TO DETERMINE THE LIMITS OF CAUSTIC/COAL THAT GIVE GOOD OPERABILITY, AS A GUIDE FOR KILN RUNS. PRODUCT COAL QUALITYATTAINED, SULFUR, ASH, VOLATILES CONTENT, BTU/LB, AND SURFACE AREA, WILL BE DETERMINED. CORRELATIONS WILL BE DEVELOPED RELATING REACTOR CONDITIONS, TEMPERATURE AND CAUSTIC/COAL RATIO, WITH PRODUCT QUALITY FOR CLEANED COAL PRODUCT.