METHOD OF MANUFACTURING BUILDING MATERIAL Russian patent published in 2000 - IPC

FIELD: building industry. SUBSTANCE: described is method of manufacturing building material using fly ash containing free MgO and CaO and large amounts of industrial waste such as fly sh, magnesium based-bisulfite lye, alkaline flow resulting from chemical fiber production and belite-aluminate cement. Method comprises treating fly ash with aqueous solution of sulfuric acid salts to form suspension which is mixed with other components and using fly ash containing free MgO and CaO. Treatment is carried out with solution of magnesium based-bisulfite lye in amount of 0.6-1.0% calculated for dry matter to form homogeneous ash slurry with bulk density of greater than 1300 kg/cubic m. Manufacture of gas-ash concrete involves using mixture comprising, wt %: said ash (in terms of dry matter), 22.6-36.2; belite-aluminate cement, 36.2-39.8; alkaline flow resulting from chemical fiber production (in terms of dry NaOH), 0.11-0.174; aluminum powder, 0.038-0.064: sulfonal, 0.00054-0.0006; and the water balance. EFFECT: cheap ecologically pure and radiation-safe gas-ash concrete. 2 cl, 3 ex, 3 tbl