铁尾矿泡沫玻璃制备及添加量研究

发布时间：2018-04-05 01:15

本文选题：铁尾矿泡沫玻璃　切入点：添加量　出处：《陕西科技大学》2017年硕士论文

【摘要】：近年来,中国工业化和城镇化发展导致了大量尾矿的产生,给环境保护带来了巨大压力,因而对尾矿的综合利用是一个迫切需要解决的课题。采用尾矿作为原料制备泡沫玻璃无疑是一个值得关注的方向,本课题主要以铁尾矿和废平板玻璃粉为主要原料,碳化硅作为造孔剂制备铁尾矿泡沫玻璃。一方面泡沫玻璃是一类具有优异保温隔热性能的节能材料,另一方面可以实现尾矿的再利用,保护环境,具有良好的社会和经济效益。采用荧光分析结合X射线衍射技术对铁尾矿化学组成和矿物相组成进行分析,结果表明铁尾矿的主要矿物成分是钾钠长石相、粘土、石英相、赤铁矿,其中钾钠长石相和粘土含量较多。铁尾矿高温行为研究结果表明,尾矿1100°C内部出现了大量熔体相,粘度急剧下降,TG-DSC结果表明熔体相形成温度在800°C以上。在此基础上以24.5wt%铁尾矿和74.5wt%废玻璃平板为主要原料,添加1wt%Si C粉体制备了铁尾矿泡沫玻璃,并对其结构和性能进行了研究,结果发现制备得到的泡沫玻璃气孔尺寸分布均匀,体积密度、抗压强度和吸水率随着发泡温度升高呈先降低后升高趋势,而气孔率则呈相反趋势;发泡过程研究表明,高温SiC颗粒与玻璃相的反应也是产生气体的一种主要方式,铁尾矿中钾钠长石相与玻璃高温熔体存在反应是发泡温度较低的主要原因,而尾矿中未反应的颗粒也起到了一定稳泡效果。将铁尾矿添加量分别设置为20 wt%、30 wt%、40 wt%和50 wt%,通过样品升温过程中形状变化和TG-DSC技术分别探测不同尾矿添加量样品发泡温度范围。结果发现,铁尾矿量的增加导致了发泡温度增加,不同尾矿含量泡沫玻璃体积密度和抗压强度随着发泡温度的增加基本上呈先降低后增加趋势,同时尾矿含量的增加导致了气孔尺寸范围进一步变宽,出现大量连通孔和大尺寸气孔,物相分析也进一步表明温度升高有助于尾矿和高温熔体之间反应进行。在此实验基础上,引入7.5 wt%硼砂得到高掺量铁尾矿泡沫玻璃,结果发现硼砂引入使得不同含量铁尾矿泡沫玻璃发泡温度大幅度下降,体积密度和抗压强度随着发泡温度升高变化趋势基本上保持不变,气孔尺寸范围分布更为宽泛,大量形状各异的气孔出现,连通孔和大尺寸气孔数量更多。在此基础上,制备了较高含量铁尾矿泡沫陶瓷,制品气孔尺寸分布较为均匀,同幕墙复合制品具有较好应用前景。
[Abstract]:In recent years, the development of industrialization and urbanization in China has led to the production of a large number of tailings, which has brought great pressure to environmental protection, so the comprehensive utilization of tailings is an urgent problem to be solved.The preparation of foamed glass with tailings as raw material is undoubtedly a focus. In this paper, iron tailings and waste flat glass powder are used as main raw materials, and silicon carbide as pore-making agent to prepare iron tailing foamed glass.On the one hand, foamed glass is a kind of energy-saving material with excellent thermal insulation, on the other hand, it can realize the reuse of tailings, protect the environment, and have good social and economic benefits.The chemical composition and mineral phase composition of iron tailings are analyzed by fluorescence analysis and X-ray diffraction. The results show that the main mineral components of iron tailings are potassium albite, clay, quartz and hematite.The content of potassium albite and clay is more.The results of high temperature behavior of iron tailings show that a large number of melt phases appear in the tailings at 1100 掳C, and the viscosity decreases sharply. The results of TG-DSC show that the formation temperature of the melt phase is above 800 掳C.On this basis, the iron tailings foamed glass was prepared by adding 1wt%Si C powder with 24.5 wt% iron tailings and 74.5 wt% waste glass plate as the main raw materials. The structure and properties of the iron tailings foamed glass were studied. It was found that the pore size distribution of the prepared foamed glass was uniform.The volume density, compressive strength and water absorption increased with the increase of foaming temperature, but the porosity showed the opposite trend. The study of foaming process showed that the reaction of high temperature SiC particles with glass phase was also one of the main ways to produce gas.The reaction between potassium albite phase and glass melt in iron tailings is the main reason for the low foaming temperature, and the unreacted particles in the tailings also play a role in stabilizing foaming.The content of iron tailings was set to 20 wt2 and 30 wt% and 50 WT, respectively. The foaming temperature range of different tailing samples was detected by means of shape change and TG-DSC technique during the heating process of the samples.The results show that the increase of iron tailings content leads to the increase of foaming temperature, and the volume density and compressive strength of foamed glass with different tailings content decrease at first and then increase with the increase of foaming temperature.At the same time, the increase of tailings content leads to a further widening of the pore size range, a large number of connected pores and large pore size, and the phase analysis further indicates that the temperature rise is helpful to the reaction between tailings and high temperature melts.On the basis of this experiment, the high content iron tailings foamed glass was obtained by introducing 7.5 wt% borax. The results showed that the foaming temperature of iron tailings foamed glass with different content was greatly decreased by the introduction of borax.With the increase of foaming temperature, the volume density and compressive strength remained unchanged, the pore size distribution was wider, a large number of pores of different shapes appeared, and the number of connected pores and large pores was more.On the basis of this, high content iron tailings foam ceramics were prepared, the pore size distribution of the products was more uniform, and the composite products of the same curtain wall had a good application prospect.
【学位授予单位】：陕西科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ171.722

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