Patent ID: 8038768

Claim:
An exhaust gas treatment method of a cement burning facility, configured to extract, as extracted gas, a part of exhaust gas that contains dust and that is discharged from a cement kiln for burning a cement raw material and sent to a preheater for preheating the cement raw material, from a lowermost part of the preheater or a kiln inlet part of the cement kiln, configured, after the extracted gas is cooled to a melting point or less of a chlorine compound, to separate the dust having a predetermined particle size or more from the extracted gas by solid-gas separation means, and to return the separated dust to the burning process of the cement raw material, and configured to collect and remove, by dust trap means, fine powder dust having the predetermined particle size or less from the extracted gas containing the fine powder dust, and to thereby remove the chlorine compound contained in the extracted gas, wherein the chlorine concentration in the collected fine powder dust is set in a range of 5 to 20% in such a manner that the cement raw material is dispersed in the exhaust gas at a lowermost part of the preheater or a kiln inlet part of the cement kiln, that the temperature of the extracted gas is held in a range of 950° C. to 1150° C. by adjusting the dispersion amount of the cement raw material, and that the predetermined particle size in the solid-gas separation means is adjusted in a range of 12 μm to 30 μm.