FREMGANGSMAADE OG ANLAEG TIL FREMSTILLING AF EN TOER CEMENTBLANDING

摘要

The invention relates to a dry cement composition comprising a certain amount of ferrous sulphate (FS) in order to eliminate or greatly reduce the amount of water- soluble chromate. The said cement composition is prepared by grinding the starting material (C,G) in a cement mill and transferring the ground cement material from the mill to a storage container 33. The ferrous sulphate is added in an amount of 0.01-10 wt-% and preferably 0.4 wt-% and is mixed with the starting material in the dry or undissolved state at one point or at two points lying upstream of the storage container 33 when considered relative to the direction of flow of the material. The ferrous sulphate is preferably added to the starting material upstream of the cement mill. <IMAGE>