Application Of The Desulfuration Residue In Aerated Concrete

The main power is coal in our country. When the coal is burning, it releases SO2 gases, which would bring acid rain and do harm to the living environment. For the sustainable development of strategic objectives, desulfurization industry expands rapidly, and lots of desulfurization products-desulfurization residues are forming. The comprehensive utilization of desulfurization residue is becoming a new research direction.Handan HuaYe new building materials factory is a company whose main products are aerated concrete blocks in level for the A3.5, B06. Along with the fly ash market demands, the production cost of aerated concrete is higher and higher, it is imperative to reduce the cost and increase economic benefits. The 6#, 7# and 8# product-lines in Matou power plant use LIFAC desulfurization technology, the by-product is desulfurization residue, except a small amount for backfill, most of desulfurization residue is abandoned and stacked in the desulfurization yard.This paper is an application-oriented research based on the comprehensive utilization of desulphurization residue, it is the first time for the desulphurization residue to be used to produce aerated concrete, then it will generate a new wall materials: Desulfurization Residue Aerocrete (Desulfurization Residue Aerocrete, abbreviated DRA), which is a new development direction for the comprehensive utilization of desulphurization residue.By chemical analysis, XRD and SEM experiment, the main mineral compositions of desulphurization residue in Matou power plant are CaO, CaSO₄ 0.5 H₂O, CaSO₃ CaCO₃. According to the similarity of fly ash and desulfurization residue in composition, the desulfurization residue will be used to produce aerated concrete in a part replacement of fly ash. By preliminary test, the dosage limits of desulfurization residue are definited. According to orthogonal design arrangement, four factors are selected, namely: the desulfurization residue dosage, cement dosage, lime dosages, and water-cement ratio, each take three levels, and nine group experiments are done. With the theoretical analysis, the optimum proportion of desulfurization residue is found out, namely 10 percent of desulfurization residue instead, cement content 40kg/m³, lime 150kg/m³, water-powder ratio with 0.60. Trial production is carried out according to the optimal proportion, and then a series of tests are done on the products, such as size and appearance of the products, compressive strength, dry bulk density, drying shrinkage and antifreezing etc. It shows that DRA products accord with quality requirements of aerated concrete. This paper shows that the desulfurization residue partly instead of fly ash for aerated concrete is feasible.