CHARACTERIZATION OF A NOVEL SUPPORTED-SORBENT FLUID-PARTICLE SYSTEM

DURING THE PAST SIX YEARS, MAJOR RESEARCH EFFORTS HAVE GONE INTO SO2-CONTROL TECHNOLOGIES BASED ON THE INJECTION OF LIME DIRECTLY INTO THE FLUE GAS DUCT. SUCH TECHNOLOGIES SHOW PROMISE AS BEING SIMPLER AND LESS COSTLY THAN CURRENT ACID-RAIN CONTROL APPROACHES. TO BE ATTRACTIVE ECONOMICALLY, HOWEVER, THE TECHNOLOGIES MUST PROVIDE HIGH SO2 REMOVALS AND HIGH SORBENT UTILIZATIONS. UNFORTUNATELY UP TO NOW, TYPICAL SO2 REMOVALS WITH LIME ALONE HAVE BEEN LOW (40 TO 60 PERCENT), AND SORBENT UTILIZATIONS HAVE BEEN DISAPPOINTING. RESEARCHERS HAVE CONCEIVED A CONCEPT TO SIGNIFICANTLY IMPROVE SO2 REMOVAL EFFICIENCY AND SORBENT UTILIZATION. THEY FOUND THAT BY COATING THE LIME ONTO AN INEXPENSIVE SUPPORT PHASE, EXPANDED VERMICULITE OR PERLITE, AND MOISTENING THE COMBINATION SLIGHTLY BEFORE INTRODUCING IT INTO THE DUCT, EXTREMELY HIGH SO2 REMOVALS WERE POSSIBLE. ALSO, BY RECYCLING THE SORBENTS, VERY HIGH UTILIZATIONS COULD BE ACHIEVED. THE CONCEPT WAS BRIEFLY EXAMINED RECENTLY AT U.S. EPA'S NORTH CAROLINA LABORATORIES WITH OUTSTANDING RESULTS. THE PROOF-OF-CONCEPT TESTING IS SPECIFICALLY AIMED AT DEVELOPING A PERFORMANCE MODEL AND TESTING THE MODEL BY CHARACTERIZING HOW CHANGES IN PROCESS AND SORBENT VARIABLES AFFECT SORBENT PERFORMANCE.