AN ADVANCED COAL METERING AND INJECTION DEVICE FOR PRESSURIZED FLUIDIZED-BED COMBUSTION SYSTEM

THE HIGH COST AND LIMITED ACCURACY AND RELIABILITY OF EQUIPMENT FOR THE METERED INJECTION OF SOLID MATERIALS INTO POSITIVE PRESSURE LIMITS THE UTILITY OF A WIDE RANGE OF INDUSTRIAL OPERATIONS AS DIVERSE AS THE INJECTION OF SOLIDS INTO TRANSPORT MEDIA AND THE METERING OF PULVERIZED SOLID FUELS TO FURNACES. A UNIQUE, PATENTED ROTARY MACHINE, THE FIRTH SOLIDS PUMP (FSP), HAS BEEN DEVELOPED WHICH CONTINUOUSLY, ACCURATELY, AND EFFICIENTLY METERS AND FEEDS VIRTUALLY ALL PARTICULATE SOLIDS INTO ATMOSPHERIC AND LOW PRESSURE SYSTEMS. FSP HAS ONLY ONE MOVING PART; HAS NO VANES, FLITES, OR OTHER WEAR-PRONE PROJECTIONS; AND PROVIDESAN EFFECTIVE SEAL AGAINST BACKFLOW. THE SYSTEM HAS BEEN DEMONSTRATED ON A WIDE RANGE OF MATERIALS AND APPLIED COMMERCIALLY AS A FINAL FEEDER IN A PULVERIZED FUEL COAL ELECTRIC GENERATING PLANT. THERE IS A CRITICAL NEED FOR SUCH A DEVICE WITH THE CAPACITY TO OPERATE AT HIGHER PRESSURES. THE WIDESPREAD UTILIZATION OF SUCH IMPORTANT NEWPROCESSES AS THE PRESSURIZED FLUIDIZED-BED COMBUSTOR (PFBC) TOPPING CYCLE, WHICH OFFERS HIGH EFFICIENCY AND ENVIRONMENTAL PERFORMANCE IN COAL-POWERED ELECTRIC GENERATION, IS IMPERILED BY THE INADEQUACY OF EXISTING EQUIPMENT TO METER AND FEED COAL AND REINJECT CHAR INTO HIGHPROCESS PRESSURES. THIS PROJECT IS DEVELOPING THE FSP FURTHER TO PROVIDE RELIABLE, CONTINUOUS, ACCURATELY METERED INJECTION OF SOLIDS INTO HIGHER PRESSURES FOR PFBC AND MANY OTHER PROCESS USES. IN PHASE I, BENCH-SCALE EXAMINATION IS BEING CONDUCTED OF THE SEVERAL FACTORS THAT AFFECT DELIVERY OF POWERPLANT COAL INTO PRESSURES UP TO THE RANGE OF 100 PSI. THE RESULT WILL BE THE DESIGN OF A FULLSCALE COMMERCIAL UNIT TO BE CONSTRUCTED AND INSTALLED FOR EXTENDEDOPERATION IN PHASE II. THE UNIT IS BEING DESIGNED TO PROVE CATEGORICALLY THAT THE PUMP SOLVES THE PROBLEMS FOUND WITH EXISTING PFBC FEEDING EQUIPMENT.