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Show • Performance and operability of commercial-size, integrated bag/catalyst arrangements • Effect of economizer injection on SOx removal performance • SOx and NOx removal performance • Compatibility of the SOx and NOx removal processes • Particulate and NH3 emissions downstream of the baghouse. The results of these tests also provided information needed to conduct a preliminary economic evaluation of the SNRB process. A schematic of the SNRB laboratory pilot-scale test facility is illustrated in Figure 3. The facility is comprised of a pulverized coal-rued test furnace (5-million Btu/hr thermal input), insulated ductwork, sorbent and ammonia injection systems, a heat exchanger to simulate a utility boiler economizer, a high-temperature SNRB baghouse, and an ID fan. The baghouse contained 12 commercialsize fabric filter bags - 6-1/4 inches in diameter and 20 feet long - yielding an overall collection area of approximately 375 ft2. The 1500 ft3 (actual)/minute baghouse was equipped with an on-line pulse-jet cleaning system. The cleaning cycle was initiated by a set-point limiting the differential pressure across the baghouse. High-temperature, woven, 3M NextePll4 bags were used along with an unpromoted zeolite SCR catalyst from the Norton Company. The catalyst was incorporated into each bag filter assembly. . The heat exchanger used to simulate a utility boiler economizer was a water-cooled, natural convection unit equipped with three independent banks of water-cooled tubes. By varying the number of banks in service. various time-temperature profiles and bag house inlet temperatures STACK 10 FAN WASTE PULSE-JET BAGHOUSE WI CATALYST were investigated. The sorbent injection system consisted of a solids feeder, air eductor, and injection nozzle. Sorbent injection was performed at various locations to investigate the effect of residence time at the injection temperature, etc. Two sorbent injection points were located upstream of the simulated economizer. The third was downstream of the economizer, but upstream of the baghouse. Ammonia vapor from a cylinder was diluted with air before being injected into the flue gas upstremn of the baghouse. An Ohio #8 coal containing 2 - 2.5% sulfur was rued to produce a flue gas containing 1500 - 2500 ppm S02, 600 - 800 ppm NOx' and 3 - 4% 02' The coal was selected to be representative of the coal burned at Ohio Edison's R. E. Burger Plant, thereby simulating expected flue gas conditions in the 5 MW e facility. The desired flue gas temperature operating temperature was obtained by mixing flue gases extracted from two different locations in the water-cooled convection pass of the test furnace. S02' NOx' and 02 concentrations in the flue gas were continuously monitored at the furnace outlet (before sorbent and NH3 injection). baghouse inlet. and baghouse outlet. Tests were typically conducted over a 3 to 4-hour period to ensure steady-state test conditions. Testing was conducted over a range of operating conditions. Major operating parameters varied during the test program included sorbent injection and baghouse operating temperatures. Ca/SOx and NH3fN0x stoichiometries, and sorbent residence times. The laboratory pilot results are briefly summarized in the following three sections. Particulate Emissions Woven. seamless bags fabricated of 3M Nextel™ ceramic fibers were used for particulate collection. One of COAL NH] INJECTION o -GAS SAMPUNG LOCA nONS Figure 3. SNRB Laboratory Pilot Facility 4 |