| 摘要 |
<p>PROBLEM TO BE SOLVED: To produce a cement clinker which is obtained by using, as a raw material, coal ash in a large amount and which is useful for producing a cement composition having stable quality and excellent in compatibility with a water reducer such as lignin or naphthalene sulfonic acid, or the like, and to provide a cement composition using the same. SOLUTION: The cement clinker is obtained by using coal ash as a raw material and has a hydraulic modulus(H.M.) of 1.8 to 2.0, a silica modulus(S.M.) of 1.8 to 2.0 and an iron modulus (I.M.) of 1.8 to 2.8 and contains water-soluble alkali in an amount of 0.2 to 0.5%. The cement composition is obtained by mixing gypsum and the cement clinker so that the total amount of SO3 becomes 2.0 to 10.0% and pulverizing, or independently pulverizing each raw material and mixing. Further, the cement composition is mixed with at least one inorganic powder selected from blast furnace slag powder, fly ash and limestone powder, and, if necessary, with gypsum.</p> |
