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Show CYCLONIC INCINERATION PERFORMANCE TESTS - SECOND SET IGT conducted a second set of incineration performance tests to attempt a reduction in auxiliary fuel (natural gas) consumption per unit of liquid waste. These tests were performed in August and September 1983 and encompassed 1) slagging attempt, 2) optimization tests in which the position of atomizers was varied and minimization of ash deposits was examined, and 3) a 48-hour continuous test. Each of these is described below: Slagging Attempt A combustion test using the incinerator configuration of the 24-hour test was conducted in an attempt to produce liquid ash and/or slag within the incinerator chamber. Goals were to 1) determine what conditions were necessary to produce liquid ash/slag, 2) quantify the amount of liquid ash/slag produced, and 3) determine the adhesion characteristics of the liquid ash/slag to the refractory surface lining of the combustion chamber interior. The waste used for this test was approximately the same composition as that used previously. The data taken during this test are shown in Table 12. An abnormally high amount of natural gas was used to purposely raise the combustion temperature within the incinerator chamber to a level as high as, or higher than the fluid temperature of the ash. The gas firing rate of 0.67 x 106 Btu/h was used in conjunction with a relatively low liquid waste-flow rate of roughly 6 gph through one atomizer. The measured temperature of 2675°F was taken using a suction pyrometer placed in the third incinerator chamber section (from the top), thereby measuring the temperature of the products of combustion. An air preheat level of about 680°F was used during the test. During firing, it was difficult to observe the formation and presence of liquid ash and/or slag on the interior surfaces of the incinerator chamber. The incinerator lid was removed, however, after the incinerator had cooled, and the following was observed: • Frozen slag deposits were present on the roof, walls, and floor (orifice) of the incinerator chamber. • The slag was dark gray in color and had a smooth, glassy surface appearance. • The slag was not a continuous layer; rather, it was deposited uniformly in spots and patches roughly 1/4 inch in diameter and 1/8 inch thick • The majority of the slag was deposited atop a layer of powdery, golden-colored ash (which is normally present) and, therefore, was easily removable. The slag on the roof (bottom of lid) was attached directly to the refractory in some spots but it, too, was removed without difficulty. 33 |