Study On FGD Gypsum-Fly Ash Wall Materials

The basic research and exploration work for making the new wall block was carried out here,in which two solid wastes of FGD gypsum and fly ash made from coal fired power plant was usedas raw materials and the cementing material was modified by adding other admixtures.Firstly, effect of single factor on desulfurization gypsum-fly ash cementing materialexperiments was experimentally studied, and the optimum mix proportion of the desulfurizationgypsum-fly ash cementing material was obtained based on the orthogonal experiment. On the basis,effect of the modified materials on improving the cementing material strength, apparent densityand water resistance function was studied, and the more proper modified materials and theirvolumes were obtained, and the goal of determining more appropriate mix proportion for makingwall block was achieved. Finally, the producing process of wall block of desulfurization gypsum-fly ash cementing material was further studied, and the production process of the proposed buildingblock was suggested through a group of block production experiment.It is concluded that（1）The optimal mix proportion of FGD Complex Binder is determinedas: Desulfurization gypsum: fly ash=1:1，CaO accounts for3%，CaCl2for1.0%，Cement for10%，Glass beads for15%，Water-proof agent for1.5%，Polypropylene fiber with length9mmfor1.5g/Kg, and water solid proportion is0.4;（2）Lower density of the FGD Complex Bindercan be realized by adding glass beads and sawdust，but the glass beads has less effect on strengthof the cementing material than the sawdust.（3）The test results according to the technicalstandard (JC/T698-1998) show that the main performance of gypsum block was qualified.The main innovations of this thesis are as:（1）The main effect of polypropylene fiber on performance of desulfurization gypsum-flyash cementation material was obtained.（2）Effect of glass beads and sawdust on density and strength of the cementing materialwas analyzed.（3）Production of the wall block and its production process were further researched basedon the test results presented here.