Patent ID: 8114190

Claim:
An exhaust gas treating method for a cement burning facility in a cement manufacturing facility in which a cement material is burned in a cement kiln, and in which organic sludge is introduced into a kiln inlet part or a calciner of a cement kiln for incineration, the method comprising: burning cement material; extracting, from a lowermost part of a preheater or the kiln inlet part of the cement kiln, exhaust gas containing dust discharged from the cement kiln and fed to the preheater that preheats the cement material, to obtain extracted gas; cooling the extracted gas to at most a melting point of a chlorine compound; separating, using solid-gas separation means, the dust of at least a predetermined particle size from the extracted gas; returning the separated dust to the kiln inlet part to be burned again; and collecting and removing fine powder dust, via dust trap means, of at most the predetermined particle size from the extracted gas containing the fine powder dust, to remove the chlorine compound contained in the extracted gas, wherein the cement material is dispersed in the exhaust gas in the lowermost part of the preheater or the kiln inlet part of the cement kiln, a dispersion amount of the cement material being adjusted to maintain a temperature of the extracted gas between 950° C. and 1,150° C., and the predetermined particle size in the solid-gas separation means being adjusted to between 15 μm and 30 μm so as to maintain an amount of the fine powder dust collected by the dust trap means between 50 g/m 3 N and 150 g/m 3 N, while maintaining a concentration of chlorine in the collected fine powder dust between 5% and 20%.