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Show Paper #4 APPLICATION OF THE THERMAL DeNOx PROCESS TO GLASS MELTING FURNACES w. D. Fellows Exxon Research and Engineering Co. The THERMAL DeNOx process is briefly described, followed by a discussion of applications to four different glass melting furnaces which represent a wide range of type and construction. Results for these applications are included, along with an estimate of the cost effectiveness of the process when applied to glass melting furnaces. The THERMAL DeNOx Process The THERMAL DeNOx process is a selective non-catalytic process for the reduction of NOx emissions from stationary combustion sources. The process is covered by u.S. and foreign patents granted to Exxon Research and Engineering Co. The THERMAL DeNOx process is based on the gas phase homogeneous reaction between NOx and ammonia (NH3) which produces nitrogen and water. For the process, NH3 is injected into the flue gas by means of a carrier, either air or steam, at a location selected to provide optimum reaction temperature and residence time. The injection of ammonia into the flue gas results in numerous intermediate chain branching reactions which can be summarized by the two simplified reactions shown in Figure 1. The THERMAL DeN Ox process can be applied to flue gas in the temperature range of 1600 degrees F to 2200 degrees Fusing ammonia alone. The effective temperature range can be extended down to 1300 degrees F by the injection of hydrogen along with the ammonia. The first reaction shown in Figure 1 is the desired NOx reduction reaction and is favored at the lower end of this temperature range. As the temperature is increased, the second reaction becomes more significant, finally dominating the process at the higher end of the temperature range. If the temperature is too low, there will be very little NOx reduction and the ammonia will pass through unreacted. If the temperature is too high, the ammonia will be oxidized according to the second reaction, causing an increase in NOx emissions. In addition to temperature and residence time, flue gas composition may also affect the performance of the THERMAL DeNOx process. Oxygen, water vapor and carbon monoxide concentrations are particularly important. Other flue gas components also need to be evaluated. For example, sulfur and chlorine compounds, |