Composition for building materials comprises of fly ash from flue gas desulfurization. The fly ash (βCaSO4 anhydrite), obtained from circulating fluidized bed flue gas desulfurization, is mixed with binder reactants at a ratio of 9:1. It's mainly used for non-structural cement mortar, bricks for paving walkways, brick wall decors, fire-resistant walls for interior partitions, plasterboards and so on. The binder reactants compose of 70% CaSO4.½H2O, 10% Na2SO4, 10% CaO, 5% NaOH, 0˜5% cement and 0˜5% starch. When the binder reactants are mixed with fly ash and water (30% to 40% of the above total weight), the hydration process of CaSO4 anhydrite is accelerated.
