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Show feet in the direction opposite of the lime bed. In addition, the waste gas gun is tilted at a 5° angle toward the kiln burner. Based on the CO concentrations shown in the 50-foot length of model in Figure 10, the kiln burner flame is about 35 to 40 feet in length (measured from the tip of the kiln burner). The flame bends upward at its end due to buoyancy effects. The waste gas bums above the main kiln burner flame as a cooler, separate flame and is about 15 feet in length. At no point is the refractory exposed to excessively high temperatures, and the lime bed at the bottom of the kiln is exposed to fairly consistent temperatures over the length of the main flame. FIELD RESULTS Unfortunately, at this time there is only a limited amount of anecdotal information available from the installation site. Shortly after the new burners were installed in late 1996, the kiln started to experience various problems at the feed end (unrelated to the burner operation), such as broken feed screws and problems in the lime m u d filtering system. Reports from the kiln area manager indicate that prior to the feed system problems, the burner was working properly with all the desired reliability and flexibility. The mill batch-bums its turpentine every other day, a procedure that saves a lot of fossil fuel energy while incinerating the unwanted turpentine at the same time. Figure 11. Installation of the kiln burner and waste gas gun. Photographs of the installation are shown in Figure 11. Before the installation of the new kiln burner, the kiln was producing 80 to 82 percent heat availability with good material quality. After the new burner was installed, the heat availability was found to have increased to about the 92 percent level, while the quality of the lime (color and texture) was also improved. The waste gas burner also appears to function well, although the waste gases to not have as high an energy content as was originally believed. Still, the lime kiln is a excellent facility for incinerating these unwanted gases. SUMMARY In this case study, a lime recovery kiln was retrofitted with equipment for firing multiple fuels. Specifically, a custom-designed kiln burner was installed with the capability of firing the liquid 8 |