Production of a concrete additive used in the building industry comprises using calcium oxide-deficient brown coal fly ash containing a maximum total lime content which is sieved and separated

摘要

Production of a concrete additive comprises using calcium oxide-deficient brown coal fly ash containing maximum 15 wt.% total lime content which is sieved in the region of 200 microns to 4 mm and separated. The remaining brown coal fly ash is divided into a coarse amount of 50-200 microns and a fine amount of less than 50 microns by classifying. The coarse amount is ground to a Blaine value of 2000-6000 square cm/g and recycled to the fine amount.