Improvements to the clinkers of portland cement, the portland cements, and for their production.

摘要

A Portland cement clinker having a silica ratio of not more than 2.80 and comprising, as an integral set-regulating component, (a) sulphate, in the presence of alkali metal in the combined state, and/or (b) halogen in the combined state, the said set-regulating component being present in an amount sufficient to prevent premature setting of cement produced from said clinker. The preferred halogen is fluorine, which can be introduced into the clinker-producing kiln in the form of calcium fluoride. It is possible to grind the clinker to form a cement, in the absence of the customary additions such as gypsum or anhydrite.