... It has not the big grain ,main use silicon material (for example: coal ash , sand , stone dust and others ) ,through ... then produce Hydrogen to make the concrete slop to expanding or swell,foam . Next , put them into the curing ... 9-0.22W/(mk),the same as 1/4 or 1/5 of clay brick ,so it is best ... coal ash ,and save coal ash using area 0.5 mu,save burning clay brick 5 mu . Good tilting table machine for ...