Air Distribution Method for the Rotary Kiln

With the burnout effect of the circulating fluidized bed in the incineration system with pyrolysis gas and solid product, the overall temperature of the circulating fluidized bed is between 850℃ to 1100 ℃. The classification of the air supply and the oxygen-enriched combustion make the reaction become strong. After the solid materials enter the circulating fluidized bed, the materials run in the fluidization shape. The is residence time is more than 40 minutes to 60 minutes, which can ensure that the solid material can burn out in the rotary kiln. The hot burning lapse rate of the ash discharged from the rotary kiln is less than 2%, which is far below the incineration standard. The combustible gas after pyrolysis in the rotary kiln can burn rapidly after it enter the circulating fluidized bed with the high turbulence fed by the classifier and high-oxygen conditions. The residence time of the flue gas in the circulating fluidized bed is more than 3 seconds to 4 seconds, which can make the available natural gas fully burn and effectively inhibit the generation of the harmful substances.
In the circulating fluidized bed of the rotary kiln, the limestone is added as the bed material. The calcium oxide produced by the limestone with the pyrolysis under the high temperature can react with the hydrogen chloride and other acid gas produced in the incineration of the medical wastes. In this way, the emission concentration of the hydrogen chloride can be reduced, which can avoid the corrosion problems of the tail equipment. The high temperature flue gas produced by the circulating fluidized bed is cooled to 500℃ through the air preheater and the pyrolysis wind and stream wind are heated to more than 500℃. The high temperature combustion air can improve the combustion temperature level in the incineration chamber so that the medical wastes can keep burning without the auxiliary of the fuel. The fuel gas from the high-temperature air preheater is cooled to less than 200℃ through the fuel cold device.