| 摘要 |
PURPOSE:To prevent an oversupply of combustible substance to the rear stage of the kiln and to decrease combustion volume by a method wherein a part of the exhaust gas in the rotary kiln which contains unburnt substance is extracted so as to be utilized as a fuel for a burner and also as a heat source for preheating combustion air. CONSTITUTION:A part of the exhaust gas G in the rotary kiln 1 which contains unburnt substance is extracted by an exhaust gs duct 4, and thus extracted gas G1 is led to an air preheater 6 through a lagging pipe 5 for use in preheating the combustion air for the burner 3. Further the gas G1 is sent via a circulation fan 7 to the burner 3 as fuel for it. In the burner 3, the gas G1 having a low heating value is added with fuel F to increase the heat value and burning characteristics, and thus obtained mixture is burnt with the combustion air A which is preheated by the preheater 6. |
