2005 年 47 巻 142 号 p. 308-316
The effects of the low air-ratio combustion on a waste incineration process have a reputation for reducing environmental pollutants such as dioxins or nitric oxides and improving the waste heat recovery. However, it was difficult to incinerate appropriately under a low excess air condition due to the combustion instability caused by heterogeneity of waste materials. Although the High-temperature air combustion technology opened the way for the realization of stable low air-ratio combustion at a stoichiometry of 1.3, it required amount of fuel for heating the high-temperature mixed gas -that is controlled oxygen concentration and preheated- up to 400°C which is injected above the fuel bed of the furnace specifically. From the point of view of the energy-saving issue, it is desirable to minimize the fuel consumption. A practical low air-ratio combustion test is conducted on an actual MSW incineration plant 105 tons per day capacity with the temperature of the high-temperature mixed gas up to 250°C that can be increased by using waste energy recovery system yields the same result as the 400°C condition. Therefore, the low air-ratio combustion can be achieved in a stoker-typed incinerator system without using an external energy. Also it deemed to have a relation between the toxic product emission and primary combustion process.