An Investigation of Aromatic Derivatives Removal by Regenerative Combustion

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13 An investigation was carried out to identify of the ignition temperature of process exhaust with a variation of inlet concentration. After the combustion chamber is heated to 850°C for two hours when regenerator bed has been soaked completely, the burner is then turned off and the process exhaust begins introduced. The results shown in Fig. 10 indicate that destruction efficiency gradually decreases as the chamber temperature decreases at the first 150°C and then drops dramatically as the temperature further decreases. The breakthrough region is defined as ignition temperature, and that is also found to increase as the inlet concentration decreases. Therefore, as combustion chamber is operated above 750°C, ceramic honeycomb regenerator bed able to preheat inlet exhaust to 650°C, that cross the ignition temperature and accelerate the destruction in upper steady-state region. In other words, crossing ignition temperature occurs at an earlier conversion of hydrocarbon is the most probable way to prevent the formation of C O and enhance the combustion reaction. On the other hand, the advantage of this highly efficient heat recovery can reduce the residence time or combustion temperature in combustion chamber in that a cost-effective and compact design of rotary combustion system is achieved. E Q. Si P OS a> o c o (J 900 800 700 600 500 400 300 200 100 Ignition Point -Qea^e^ -s-llOOppm -•-950ppm 750ppm •e- 375ppm o o o -&-e 550 600 650 700 750 8C Furnace Temperature (C) 850 900 Fig. 10 The relationship of ignition temperature with inlet concentration