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Show 1 Combustion Method to Reduce NOx and Save Fuel for burners for Forge Furnace Shun Yamaqami Osaka Gas Co., Ltd. Abstract To save fuel in a forge furnace, it is effective to recover heat by pre-heating combustion air. This requires a choice out of recuperators, recuperative burners and regenerative burners in proportion to the size or type of the furnace. Then w e have worked out the methods to reduce NOx for each system realistically with due regard to the cost and put them into practice. For the regenerative burner, assuming that most of the NOx is formed at the flame retaining area, w e designed a very simple one whose combustion ratio of the flame retaining area is very small so that the retention flame is made up of very little ambient temperature auxiliary air. The simplicity of the burner has reduced not only N O x but also the cost of the overall regenerative system. In a forge furnace with the developed regenerative burner, w e achieved N O x emission less than 200 ppm (O2=0%,1300°C furnace temperature) and a fuel saving rate of about 5 0 % . 1. Introduction It is well known that the regenerative burner system is effective in high temperature furnaces from the point of energy savings and further attention from the industry is being seen with the recent increased interest in reducing C 0 2 emission. On the other hand, a slowdown of the Japanese economy is being seen since the beginning of the 90's and a conspicuous reduction in facility operating rates has resulted, especially with the small to medium scale factories. Although there are many heating furnaces for forging in these factories, the energy consumption per furnace is relatively small. The large scale regenerative burners developed for large heating furnaces for hot rolling are facing problems in regard to recovery of facility investments and the introduction of this system for such a small furnace has not seen progress in Japan. We have therefore developed recuperators, low NOx recuperative burners and regenerative burners with importance attached to the economy of forge furnaces. In realizing of low N Ox which is an issue in pre-heated air waste heat recovery technology, w e have developed methods which are simple as possible to hold down costs while obtaining the maximum effect. As shown |