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Show output, decrease the excess air utilized by the main process bumer(s), which will increase the flame temperature and reduce thermal losses, reduce property (e.g., temperature and oxygen distribution) nonuniformities within the process, which may improve product and process quality, and reduce emissions. To date, most of these benefits have been demonstrated2^.4 in tests involving water evaporation, limestone calcining, metal heating, and incineration of a variety of wastes. In addition, a recent investigation5 of the incineration of chlorinated hydrocarbons (i.e., carbon tetrachloride and chlorobenzene) in a Cello burner that was attached to EPA's Rainbow tunnel furnace (in Research Triangle Park , North Carolina) have demonstrated destruction efficiencies of these compounds higher than 99.9999% under all operating conditions, which included pulsing and nonpulsing tests. Cello burner installations currently exist in a cement calciner, an asphalt sand dryer, a steel ladle preheater and an E P A incinerator in R T P , North Carolina. Another is currently being developed for testing in an E P A incinerator in Jefferson, Arkansas as part of EPA's SITE (Superfund Innovative Technology Evaluation) program. This paper will be limited to the discussion of results in obtained in the RTP installation in a program supported by an E P A SBIR grant. This study was joint Sonotech - E P A program and its objective was the evaluation the effects of resonant pulsations excited within the incinerator by a Cello burner upon puffs emissions. The latter is a c o m m o n problem, which generally occurs when fuel rich conditions temporarily occur within an incinerator due, for example, the instantaneous release or nonuniform supply of waste within the incinerator without a corresponding increase in the supply of combustion air. Experimental Apparatus This investigation was conducted in an EPA rotary kiln incinerator simulator (RKIS) that was retrofitted with a Sonotech Cello burner, which was used as the incinerator's main burner. The benefits of the Cello burner were evaluated by measuring incinerator emissions when the same waste was incinerated with and without the excitation of pulsations within the incinerator. The retrofitted RKIS has been described in detail previously**.7, and it has been established that the 73 k W (250,000 Btu/hr) pilot-scale simulator 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. Containerized batch charges were introduced through a sliding gate/ram assembly located downstream of the continuous natural-gas-fired 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 0 2 , C O , C 0 2 , N O x , and total volatile hydrocarbon (THC) concentrations measured by continuous flame ionization detection (FID) and reported in equivalent parts per million methane. Other dependent variables include the time-integrated responses of the C O and T H C analyzers and particulate filter weight. At constant sampling conditions, these variables are proportional to the total mass emitted in the transient puff. Tarred quartz filters and the heated particulate filter system upstream of the T H C analyzer were used to collect particulate samples. Volatile hydrocarbons are defined as those in the gas-phase at 420 K (300 °F), the temperature of the heated sample line. All experiments were performed at the same RKIS operating conditions of 1060 K (1450 °F) and 12.5% flue gas oxygen. All sampling was performed at Sample Port 1 as shown in Figure 1. 3 V-28 |