AN INNOVATIVE DEVICE TO ENHANCE JET PULSE CLEANING OF CERAMIC CANDLE FILTERS

THE NEW SOURCE PERFORMANCE STANDARDS (NSPS) AND RECENT CLEAN AIR ACT AMENDMENTS HAVE PRODUCED AN URGENT NEED FOR HIGHLY EFFICIENT PARTICULATE AND AIR TOXICS REMOVAL DEVICES, ESPECIALLY FOR COAL COMBUSTION AND COAL GASIFICATION. PARTICULATE LEVELS MUST BE REDUCED TO NEARLY UNDETECTABLE LEVELS IN HIGHLY CORROSIVE, HOT GAS STREAMS. VERY FEW TECHNOLOGIES SEEM TO MEET THESE REQUIREMENTS, EXCEPT FOR CERAMIC CANDLE FILTERS. FOR YEARS, CERAMIC CANDLE OR "BARRIER" TYPE FILTERS HAVE KNOWN TO YIELD EXCELLENT PARTICULATE REMOVAL LEVELS, AT TEMPERATURES OF 2,000 DEGREES FAHRENHEIT AND ABOVE. RECENTLY, ADVANCES IN CERAMICS AND CERAMIC BINDER TECHNOLOGY HAVE GREATLY ENHANCED THE OVER-ALL DURABILITY OF THE CERAMIC FILTER ELEMENTS. A RECENT CONCEPT, INVOLVING CERAMIC FILTER ELEMENTS COMPOSED OF CHOPPED CERAMIC FIBERS, APPEARS TO EXCEED THE DURABILITY EXPECTATIONS OF BOTH POWER-GENERATING AND TURBINE COMPANIES. ALTHOUGH CERAMIC CANDLE MATERIAL ADVANCES HAVE BEEN SIGNIFICANT, FEW ADVANCES HAVE BEEN MADE IN OPTIMIZING THE CERAMIC CANDLE JET PULSE CLEANING METHODS. THE PHASE I PROJECT IS STUDYING THE DESIGN AND OPTIMIZATION OF AN INNOVATIVE DEVICE TO ENHANCE THE JET PULSE CLEANING OF CERAMIC CANDLES. SEVERAL OF THESE DEVICES ARE BEING BUILT AND TESTED, UNDER VARIOUS FLOW CONDITIONS AT AMBIENT TEMPERATURES. PHASE II WILL APPLY PHASE I RESULTS TO A HIGH TEMPERATURE SCENARIO AND THEN DEVELOP DESIGN CRITERIA FOR THE DEVICE.