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Show Experimental System Description Experiments were conducted in the 6-inch diameter laboratory-scale fluidized-bed combustor located on-site at the Morgantown Energy Technology Center. The laboratory-scale fluidized-bed combustor is a refractory lined cylindrical vessel (see Figure 2). The reactor's inside diameter varies along the vertical axis from 6 to 8 inches. From top to bottom the combustor consists of 74 inches of an 8-inch diameter expanded freeboard section above a 6-inch diameter bed region, 16 inches in height. A heat exchanger with approximately 3.6 square feet of surface area runs along the periphery of the bed region and is used to control bed temperature. Air is fed through a conical-shaped distributor plate which has an open area of 0.59 percent of the total distributor plate area. Solids are extracted from the bed via an overflow port located approximately 4^ inches from the bed bottom and/or from a drain located in the center of the distributor. Fines elutriated from the bed are recovered by a set of cyclones. A fines recycle port is located at about 10 inches above the bed, although it was not used in the testing. Fuel and limestone are fed to the combustor by screw feeders at a height of \\ inches and 12 inches above the bed, respectively. Temperature is measured continuously at various distances along the combustor' s vertical axis and recorded by a strip chart. Pressure is measured at the combustor's exit and across the distributor plate. The products of combustions (POC) are analyzed continuously for concentrations of C02, CO, 02, NO , S02, and total hydrocarbons (THC). The results from the analyzers are also recorded by a strip chart. Table 2 lists the make and types of analyzers utilized. The char was metered into the fluidized bed by a screw feeder. The ash was collected and the carbon content of the ash was determined. These data then allowed for the calculation of the carbon conversion efficiency. The analysis of the gaseous products of combustion provided a second method for calculating the carbon conversion efficiency. Although the two carbon conversion efficiencies agreed to within ±3 percent, there was a higher degree of confidence in using the carbon-ash data. 22-6 |