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Show EXPERIMENTAL APPROACH The EPA rotary kiln incinerator simulator has been described in detail previously,1,2 and therefore, is not presented again here. It has been established that the simulator, although sized at only 73 kW (250,000 Btu/hr), exhibits the salient features of full-scale units with thermal ratings 20 to 40 times larger. The simulator matches the volumetric heat release, gas-phase . residence time, and temperature profile of many full-scale units, and yet is flexible enough to allow parametric testing. A schematic drawing of the simulator is presented in Figure 1. The water-cooled prototype burner is designed to produce stable flames utilizing oxidant streams ranging from 22 to 100 percent oxygen. The burner provides for separate introduction of natural gas, air, and oxygen with turn-j down ratios of at least 1 to 10. The burner is easily ignited and capable of rapid response to changes in the fuel, air, or oxygen flows. Liquid oxygen was provided in cryogenic Dewar tanks, with each tank containing approximately 127 m3 (4500 scf) of gaseous oxygen. Contained batch charges to the rotary kiln are introduced through a sliding gate/ram assembly located downstream of the continuous natural-gasfired oxygen-enriched main burner as shown in Figure 1. Quantification of the transient puff produced requires the real-time measurement of system response variables. These dependent variables include peak responses of 02, CO, C02, NOx, and total volatile hydrocarbon concentrations (THC) measured by continuous flame ionization detection (FlO) and reported in equivalent parts per million methane. Other dependent variables include the timeintegrated responses of the THe analyzer and particulate filter weight. At constant sampling conditions, these variables are proportional to the total 5 |