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Semidry desulfurization technology has a simple process, less area, sewage discharge, etc., but its byproduct the desulfurization ash generated high composed of calcium sulfate, calcium sulfite and residual desulfurization agent-based, is a potential the resources currently used approach directly stacked and landfill, not only cause environmental pollution and waste of useful resources. Therefore, desulfurization ash Comprehensive Utilization of this urgent problem, has also become important factors restricting the development of flue gas desulfurization technology. Iodometric method and scanning electron microscopy, the X-ray diffractometer, particle size distribution, heat - differential thermal analyzer means of modern analytical testing, three desulfurization ash chemical composition, physical properties, particle morphology and thermal stability other physical and chemical characteristics of the analysis and research. The results show that: 1) desulfurization ash chemical composition of the steel mills and power plants no significant difference in phase composition CaSO3, CaSO4, CaCO3, Corundum and mullite stone, such as. The steel mills desulfurization ash CaSO3 and MgO content is relatively low, CaO and Fe2O3 content. 2) steel mills semidry ash particle size distribution between 7.24 ~ 8.06μm, the median diameter 5.83μm; plant desulfurization ash particle size distribution between 222.66 ~ 247.83μm,, where the median diameter were 206.68μm, 208.11μm, steel mills the desulfurization ash particles diameter smaller than the power plant desulfurization ash diameter. 3) the steel mills sintering flue gas desulfurization ash particles is irregular in shape, is porous particles, the surface is smooth, loose structure. Through to the desulfurization ash, fly ash as the main raw material, mixed with a certain amount of activator, aggregate, studies have shown that preparation of steam-cured brick: # 2 Gray to test block optimal ratio: 25% desulfurization ash, pulverized coal Ash 49%, the gravel than 2:3 aggregate 25%, 1% composite activator NH. 3 # optimal ratio: 40% desulfurization ash, fly ash and 34%, the gravel than 2:3 aggregate 25%, 1% composite activator NH. The main process parameters affect the desulfurization Huizhuan the optimal formula based on research to determine the # 2, the 3 # the desulfurization Huizhuan the watered amount to 25%. Digestion time were 36 h, 24 h. Curing system: the curing temperature of 90 ° C, 95 ° C; curing time of 7 h, 8 h conditions, 2 # desulfurization Huizhuan durability experiments, its frost resistance, shrinkage, brick mechanical properties meet JC239 2001 fly ash bricks \Industrialized expand in test preparation of standard brick and hollow brick compressive and flexural strength, 15 freeze-thaw cycle loss rate, dry shrinkage tests show, the indicators are in line with GB/T2542-2003 the wall bricks test methods \
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