Experimental Study Of The Calcium Silicate Board Preparation By Using Calcium Silicate Slag, Gypsum, Fly Ash And Other Solid Wastes

In this paper, the calcium silicate sheet as a new kind of building materials was be preparedby calcium silicate slag, flue gas desulfurization gypsum and high-alumina fly ash. All thismaterials are industrial residues that come from Inner Mongolia tuo county power plant.In this paper, the physical and chemical properties of calcium silicate slag, flue gasdesulfurization gypsum and fly ash ware researched, and pretreatment of calcium silicate slagwas studied. The autoclaved curing process of silicate slag sheet ware explored. The industrialtrial productions meet the requirements in national standard of JC/T564.2-2008. Themicrostructure, structure characteristics and generation mechanism of production was tested byXRD, TG-DSC, SEM-EDS and Raman spectrum.The alkalinity of calcium silicate slags were3.33%. It was approved that mild re-alkali testspecimen can be produced under the condition of the calcium silicate slag content of40%. Andfly ash can inhibit the alkali to a certain extent. The alkalinity can be reduced to1.02%by threetimes after rinsing.It was approved that the calcium silicate sheet can be produced by desulfurization gypsum,calcium silicon slag, fly ash and cement based on the properties research of those raw materialsand related experiments. And the best ratio of components was follows:50%of calcium silicateslag,10%of cement,20%of fly ash, and20%of desulfurization gypsum.The best conditions of autoclaved curing was180and8h according to the conditionexperiment study.The composition of calcium silicon slag and fly ash were complex through the analysis ofthe microstructure of calcium silicon plate. The XRD analysis shows that the test of calciumsilicon plate main ingredients for tobermorite and xonotlite, as well as part of the ettringite,calcium hydroxide, quartz, etc. The SEM test shows that the specimen to generate a largenumber of xonotlite fibers, ensure the strength of calcium silicon plate, but part of ettringite andcalcium hydroxide, can reduce the intensity of the calcium silicon panels, part of the fly ashparticles incomplete response. The Raman spectroscopy analysis of fly ash and calcium silicon slag into Al is part of the C-A-S-H in the gelation.Through the industrial trials show that calcium silicon slag, desulfurization gypsum and flyash in the production of calcium silicon plate is practical, can industrialized production meet thenational standards of silicon calcium board, and fully use the existing equipment technology,and do not need to upgrade the equipment modification.