Patent ID: 9598312
Date: 2017-03-21
CPC Classifications: C04B

Claim:
1. A method for controlling a free lime content of a cement clinker, comprising: adding fluorite or fluorine-containing waste that is a fluorine source in the cement clinker and used as a mineralizer to raw materials of the cement clinker, intermixing a waste gypsum board powder with fuel or putting the waste gypsum board powder into a kiln from the kiln outlet part as an SO burning the raw materials of the cement clinker added the fluorite or the fluorine-containing waste in the kiln to produce the cement clinker, calculating the free lime content (f.CaO) of the cement clinker according to Formulas (1) to (3), adjusting an additive amount of fluorite or fluorine-containing waste and an used amount of fuel or an additive amount of waste gypsum according to the calculated free lime content to control the free lime content (f.CaO) so as to fall within a range of 0.5<f.CaO<1.0, in Formula (1), f.CaO is a free lime content (wt %), SO a is a coefficient satisfying Formula (2), b is a coefficient satisfying Formula (3), F is an amount (mg/kg) of fluorine in the cement clinker, t is a coefficient determined based on a temperature of 1450° C. (when a burning temperature is X° C., t=X/1450), and HM is a hydraulic modulus.