利用北京地区细颗粒铁尾矿制备多孔陶瓷工艺及性能研究

发布时间：2018-04-17 03:00

  本文选题：铁尾矿 + 多孔陶瓷　； 参考：《北京交通大学》2017年硕士论文

【摘要】：随着工业和社会的发展,资源节约与环境保护是当今人类社会所面临的两大难题。据统计,截止到2014年底,我国堆存的各类矿山尾矿为146亿吨。目前,多孔陶瓷作为一种新型的过滤材料,已经在很多方面得到了广泛的应用。以尾矿为原料制备多孔陶瓷,能够将污染环境的工业固体废弃物转变为节能环保的工业新产品,对于我国的环境保护事业具有十分重要的意义。本文以北京密云地区首云矿业集团公司2015年铁矿石开采产生的泥状细颗粒铁尾矿为主要原料,采用搅拌发泡-凝胶注模成形、常压烧结工艺制备铁尾矿多孔陶瓷。结合XRD分析、SEM微观分析以及多孔陶瓷物理性能与力学性能测试,研究了料浆固相含量、烧结温度和保温时间等因素对材料结构和性能的影响。并对铁尾矿多孔陶瓷的粉尘过滤效果进行了测试,取得了良好的实验结果。论文取得以下主要研究成果:(1)在1100°C保温3h的烧结条件下,随着成形工艺中铁尾矿料浆固相含量的增加,多孔陶瓷的线收缩率降低、显气孔率下降、孔径变小,体积密度和抗压强度增大、孔壁变厚。综合考虑铁尾矿多孔陶瓷的孔隙率和强度,成形时铁尾矿料浆的最佳固相含量为45wt.%,所制备多孔陶瓷的体积密度、显气孔率和抗压强度分别为 0.42g/cm3、83%、1.45MPa。(2)在料浆固相含量为45wt.%,烧结保温3h的条件下,研究了 1070～1120°C温度区间内烧结温度对多孔陶瓷结构和性能的影响。综合分析表明,在1100℃保温3h制备出的铁尾矿多孔陶瓷性能最佳。(3)在料浆固相含量为45wt.%,烧结温度为1090°C的条件下,研究了 3～11h区间内保温时间对多孔陶瓷结构和性能的影响。结果表明,随着保温时间的延长,烧结制品的线收缩率、体积密度和抗压强度均呈上升趋势,而吸水率和显气孔率则呈下降趋势。微观分析发现,随保温时间延长,多孔陶瓷内部的玻璃相含量逐渐增多。综合分析表明,1090°C保温7h制备的多孔陶瓷样品性能最优,其体积密度、显气孔率和抗压强度分别为0.43g/cm3、84%、1.42MPa。(4)采用气孔率为81.8%的多孔陶瓷进行了抗热震及耐酸碱腐蚀性测试,结果表明在900°C～室温的热震试验中,多孔陶瓷的平均抗热震次数为50次,热震30次后强度损失率约为50%。经酸、碱溶液微沸状态下浸泡腐蚀1h之后,多孔陶瓷的重量损失率分别为3.45%和2.11%。(5)采用气孔率分别为80.8%和84.9%的两种多孔陶瓷进行了粉尘过滤测试,结果表明在1m/min的风速下,两种多孔陶瓷的过滤阻力分别为174.39Pa和169.49Pa,粉尘过滤效率均高达99%。本文研究结果表明,采用细颗粒铁尾矿制备多孔陶瓷材料工艺简单,成本低廉,可规模化生产,所制备多孔陶瓷满足工业废气除尘的要求,在该领域具有广阔的应用前景。
[Abstract]:With the development of industry and society, resource conservation and environmental protection are two major problems facing human society.Statistics show that by the end of 2014, 14.6 billion tons of mine tailings have been deposited in China.At present, porous ceramics, as a new filter material, have been widely used in many fields.The preparation of porous ceramics using tailings as raw material can transform the industrial solid waste which pollutes the environment into a new industrial product of energy saving and environmental protection which is of great significance to the environmental protection of our country.In this paper, iron tailings porous ceramics were prepared by agitation foaming and gel injection molding and sintering under atmospheric pressure using the mud-shaped fine grained iron tailings produced by iron ore mining in Beijing Miyun Mining Group Company in 2015.The effects of solid content of slurry, sintering temperature and holding time on the structure and properties of porous ceramics were studied by means of XRD microanalysis and physical and mechanical properties test.The dust filtration effect of iron tailings porous ceramics was tested and good experimental results were obtained.The main research results are as follows: (1) under the condition of sintering at 1100 掳C for 3 h, with the increase of solid content of iron tailings slurry, the linear shrinkage, apparent porosity and pore size of porous ceramics decrease.The volume density and compressive strength increase and the hole wall becomes thicker.Considering the porosity and strength of iron tailings porous ceramics, the optimum solid content of iron tailings slurry is 45wt. and the bulk density of the porous ceramics is obtained.The effect of sintering temperature on the structure and properties of porous ceramics in the temperature range of 10701120 掳C was studied under the condition that the apparent porosity and compressive strength were 0.42g / cm ~ 3 / 83and 1.45MPa. / m ~ (2) respectively. Under the condition that the solid content of slurry was 45wt. and the sintering time was 3h, the effect of sintering temperature on the structure and properties of porous ceramics was studied.The comprehensive analysis shows that the optimum properties of iron tailings porous ceramics prepared at 1100 鈩，

本文编号：1761743