| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent occurrence of excessive temperature rise of catalyst caused by catalyst combustion and thermal damage of an exhaust heat recovery part, by using a lean combustion type gas engine so as to reduce NOx, in the case of removal of unburnt gas which is likely to form the lean combustion type engine with the use of an oxidation catalyst. SOLUTION: In a cogeneration system in which an oxidation catalyst device 4 is provided in an exhaust gas passage 3 extending from a gas engine 1 to an exhaust heat recovery part 2, a cooling air supply pipe 7 is merged into the passage 3 upstream of the oxidation catalyst device 4, through the intermediary of a regulating valve 5, and is incorporated therein with temperature sensors 8a, 8b for detecting a temperature of the catalyst device 4. With this arrangement, cooling air is fed into the exhaust gas passage 3 while the volume thereof is changed in accordance with outputs form the sensors 8a, 8b.</p> |
