【作者】 马永贤；

【导师】 任爱玲；

【作者基本信息】 河北科技大学 ， 环境工程， 2010， 硕士

【摘要】 半干法脱硫技术具有流程简单、占地面积少、无污水排放等优点,但其副产脱硫灰生成量较高,组成上以硫酸钙、亚硫酸钙和残余脱硫剂为主,是一潜在的资源,目前常用的处理方法是直接堆放和填埋,不但造成环境污染,而且浪费有用资源。因此,对脱硫灰的综合利用研究成为当前急需解决的问题,也成为制约烟气脱硫技术发展的重要因素。本文采用碘量法及扫描电镜、X-射线衍射仪、粒度分布、热重-差热分析仪等现代分析测试手段,对三种脱硫灰的化学组成、物理性质、颗粒形貌和热稳定性等理化特性进行了分析和研究。结果表明:1)钢厂和电厂脱硫灰化学成分无明显差别,物相成分主要有CaSO3、CaSO4、CaCO3、刚玉及莫来石等。钢厂脱硫灰CaSO3和MgO的含量相对低,而CaO和Fe2O3的含量较高。2)钢厂半干法脱硫灰的粒径主要分布在7.24~8.06μm之间,其中位径为5.83μm;而电厂脱硫灰的粒径主要分布在222.66~247.83μm之间,其中位径分别为206.68μm、208.11μm,钢厂脱硫灰颗粒直径小于电厂脱硫灰直径。3)钢厂烧结烟气脱硫灰颗粒为不规则形,呈多孔状颗粒,表面光滑,结构疏松。通过以脱硫灰、粉煤灰为主要原料,掺加一定量的激发剂、骨料,制备蒸养砖的研究表明:2#灰转试块最优配比为:脱硫灰25%,粉煤灰49%,砂石比2:3的骨料25%,1%复合激发剂NH。3#最优配比为:脱硫灰40%,粉煤灰34%,砂石比2:3的骨料25%,1%复合激发剂NH。在最优配方基础上,对影响脱硫灰砖主要工艺参数进行了研究,确定2#、3#脱硫灰砖的掺水量为25%。消化时间分别为36 h、24 h。养护制度分别为:养护温度90℃、95℃;养护时间7 h、8 h的条件下,对2#脱硫灰砖进行耐久性实验,其抗冻性、收缩性良好,砖力学性能均符合JC239-2001《粉煤灰砖》MU15强度等级标准。在工业化扩大中试验中,通过对制备的标准砖和空心砖进行抗压、抗折强度,15次冻融循环损失率,干收缩值的测试表明,其各项指标均符合GB/T2542-2003《砌墙砖试验方法》和JC239-2001《粉煤灰砖》中的标准要求。更多还原

【Abstract】 Semi-dry FGD technology has some advantages, such as simple process, small space-occupy and no sewage discharge, but the output of byproduct—desulfurization ash is higher, which is composed of calcium sulfate, calcium sulfite and residual desulfurizer etc. Desulfurization ash is a potential resource, direct stacking and landfill is the mainly approach ,which is not only cause environmental pollution, but also a waste of useful resources. Therefore, the comprehensive utilization of ash on desulfurization research become the current pressing problems, and also a constraint to the development of flue gas desulphurization technology .In this paper, chemical composition, physical properties, particle orphology ,thermal stability of the three kinds of desulfurization ash were analysised and studied by odometric method and scanning electron microscopy, X-ray diffraction, particle size distribution, TG - DTA and other modern analytical methods.The results are as follows.1) There is no significant difference in chemical composition of the three desulfurization ash.Phase composition are mainly CaSO3, CaSO4, CaCO3, corundum and mullite, etc.Steel desulfurization ash has lower content of CaSO3 and MgO ,while the higher content of CaO and Fe2O3.2) Steel desulfurization ash particle size is 7.24 ~ 8.06μm, with median diameter is 5.83μm; while the power plant desulfurization ash particle size is222.66 ~ 247.83μm, with median diameter, respectively 206.68μm, 208.11μm, therefore steel desulfurization ash particle diameter is less than diameter of power plant desulfurization ash.3) The research on steam-cured brick preparated by desulfurization ash, fly ash as main raw material, admixing a certain amount of excitation agent, aggregate,Studies have shown that the optimal ratio of 2# ash turn are as follows: desulfurization ash25%, fly ash49%, sand and gravel aggregate than the 2:3 of 25%, 1% of the compound activator NH; 3# ash turn: desulfurization ash40%, fly ash34%, sand and gravel aggregate than the 2:3 of 25%, 1% of the compound activator NH. Based on the optimal formula , the main process parameters were studied, water 25% , digestion time 36h,24h, curing 7 h at 90℃,8h at 95℃.2# desulfurization gray bricks on the durability test carried out:frost resistance and shrinkage of the steam-cured bricks perform well and the technical performance can meet the requirements of MU15 in"fly ash brick"(JC239-2001). In industrialized expanding test, prepared standard brick and hollow bricks for compressive, flexural strength, 15 times the loss rate of freeze-thaw cycles, dry shrinkage value of the test that its indicators are in line with "puzzle wall test method"(GB/T2542-2003)and "fly ash bricks"(JC239-2001).更多还原