OCR Text |
Show 12 the left, at inlet temperature TiE, Q„ and Q, intersect each other tangentially at E, and this phenomenon is termed as extinguished temperature in that no reaction takes place. To fasten the combustion reaction rate or reduce the residence time in combustion chamber for small concentration treatment, inlet process exhaust must be preheated to exceed ignition temperature, however, ignition temperature of most aromatics as well as chlorinated compounds are in a range of 550 ~650°C (15), which is beyond the limitation of conventional heat exchanger can achieve and that results in both oxidation and combustion have to occur in combustion chamber. Moreover, for those unable to cross the ignition temperature may form carbon monoxide( C O ) , a partial oxidation product in the oxidation region before introduced to combustion chamber, which is difficult to oxidize and higher temperatures or longer residence time are required for complete destruction. Therefore, the capability of highly efficient heat recovery by honeycomb regenerators, described in Fig.8, is an advantage to overcome the difficulty to obtain high temperature preheating inlet exhausts. Inlet exhaust gas temperature-* Fig.9 The effect of preheating inlet temperature on destruction |