【作者】 曹阳；

【导师】 印万忠；

【作者基本信息】 东北大学 ， 矿物加工工程， 2015， 博士

【摘要】 在我国,95%的能源和85%的原材料来自矿产资源,矿产资源在开发利用的同时,会产生一系列的环境问题。其中,尾矿作为一种重要的矿业固体废弃物,同时也是一种重要的原材料资源。在矿产资源开发的过程当中丢弃了大量尾矿,在造成环境污染的同时也使尾矿中可以被利用的组分被丢弃,造成了资源的浪费。因此,针对尾矿综合利用开展试验研究工作对于解决环境问题和资源浪费问题有着重大的意义。无机矿物聚合物材料是近些年来无机材料领域的研究热点,因为这种矿物聚合材料具有优异的物理化学性能,制备过程中能耗低,原料广泛,易于加工,因此受到学者们的广泛关注。本试验以取自内蒙古白云鄂博的铁矿尾矿和来自福建金东矿业公司的铅锌尾矿作为原料,进行新型无机矿物聚合材料的制备及机理研究。首先,对尾矿进行了化学组成、物相分析以及微观形貌的分析,虽然尾矿中含有一定的硅铝质,但是活性并不高,因此要采取一定的活化措施进行处理,以使有用的组分在碱激发反应的过程中可以被有效利用。通过大量试验,选取加碱煅烧的活化方式对尾矿进行处理,通过X射线衍射、红外光谱以及扫描电镜对活化处理前后的尾矿进行分析。然后,通过正交试验和单因素试验分析尾矿制备无机矿物聚合材料的试验因素及水平,并对其性质进行研究,对比分析了由两种尾矿制备的材料的各项差异。最后,重点研究了发泡无机矿物聚合材料的制备及性能。通过以上的试验得出以下主要结论：(1)加碱煅烧活化确实能提高尾矿的活性,活化后的尾矿制备的无机矿物聚合材料试块的抗压强度更大,提高了材料的各项性能指标。(2)以抗压强度为考察标准,各影响因素对无机矿物聚合物材料影响由强到弱的顺序是：尾矿占固体粉料的比例>液固比>碱激发剂模数>水玻璃掺量(以Na2O计)。(3)各单因素的最佳值分别为：尾矿掺量均为20%,水玻璃模数为1.2,水玻璃掺量(以Na20计)为5%,液固比为0.55。 (4)将由尾矿制备的无机矿物聚合材料和由普通硅酸盐水泥制备的试块性质进行了对比试验分析。结果表明：在力学性能、抗冻融循环性能、耐酸性、碱集料反应以及耐高温性方面,尾矿制备的无机矿物聚合物材料表现优于普通硅酸盐水泥。(5)通过大量的基础试验,选取双氧水和硬脂酸作为制备发泡材料的发泡剂和稳泡剂,结果表明：双氧水最佳掺量为0.5%,硬脂酸的最佳掺量为1%。(6)制备的发泡制品的导热系数分别达到了0.0511w/(m·k)和0.0524 w/(m·k)。本论文的创新点是：(1)将铁矿尾矿与铅锌尾矿作为原材料制备无机矿物聚合物,有效实现了矿产资源的综合利用。(2)无机矿物聚合物的聚合机理更加深入的解析。(3)将发泡材料与无机矿物聚合物材料的制备结合起来。通过以上的研究结果表明,这两种选矿尾矿是可以被用来制备无机矿物聚合材料的,并且通过控制试验的因素可以取得性能相对优良的产品。尾矿的再利用与无机矿物聚合材料优异性能的结合不仅解决了环境污染和资源浪费的问题,也拓宽了无机矿物聚合材料原料的使用途径,实现了废料的利用。Utilization of iron tailings and lead-zinc tailings for the preparation of geopolymer更多还原

【Abstract】 In China,95% of energy and 85% of raw materials come from mineral resources, the exploitation and utilization of which will bring a series of environmental problems. As a primary type of solid mining wastes, tailings are also a major source of pollution. In the exploitation of mineral resources, considerate amount of tailings are thrown away, which would not only cause pollution but waste the exploitable resources in the tailings. Therefore, for the protection of environment resources, an experimental investigation on the comprehensive utilization of tailings is of great significance.Thanks to their superior physicochemical properties, low energy consumption in preparation, abundance and ease of processing,geopolymer has attracted great attention from researchers and been under intensive study in the field of inorganic materials.We used the tailings of rare earth element-containing iron ore from Bayan Obo, Inner Mongolia and Lead-zinc tailings from Fujian Jindong Mining Co., Ltd in the preparation of and mechanism study on this geopolymer.First, analyses were conducted on the chemical composition, phase and microstructure of the tailings. Though the tailings had some salic content, its activity was low. So some activation measures were taken in order to ensure the effective utilization of useful components during the process of alkali excitation. After a lot of experiments, we decided to activate the tailings by calcination with alkali and made an all-round analysis on the tailings before and after activation with X-ray diffraction, infrared spectroscopy and scanning electron microscope. Then, experimental factors and performance of preparation of inorganic mineral polymers with tailings were studied in orthogonal test and single factor test. The properties of geopolymer and the differences between the two were investigated. Finally, great attention was devoted to the investigation of preparation and properties of foamed geopolymer..Based on the above experiments, we draw the conclusions:(1) activation by calcination with alkali can improve the activity of tailings; the compressive strength of thegeopolymer made of activated tailings is stronger and the performance of this material is improved in every aspect. (2) based on mechanical properties, the order of influences (in declining trend) of the factors on geopolymer is:proportion of tailings in solid powder> liquid-solid ratio> modulus of alkali-activator> added quantity of water glass (in Na2O). (3) the optimum value of each factor is:addition of tailings 20%, modulus of water glass 1.2, proportion of water glass (in Na2O) 5%, liquid-solid ratio 0.55. (4) a contrastive experimental analysis on the properties of geopolymer made of tailings and that of ordinary Portland cement was conducted. The results indicate that in terms of mechanical property, freezing and thawing resistance, acid resistance, alkali-aggregate reaction and high temperature resistance, geopolymer made of tailings surpass ordinary Portland cement. (5) based on a lot of preliminary experiments, hydrogen peroxide and stearic acid were chosen as foaming agent and foaming stabilizer of foaming materials. The results show: optimum proportion of hydrogen peroxide is 0.5%, optimum proportion of stearic acid is 1%. (6) heat conductivity coefficients of foamed materials reached 0.0511w/(m·k) and 0.0524 w/(m·k) respectively.This paper is innovative in the following aspects:(1)The use of iron ore tailings and lead-zinc tailings as raw materials to produce geopolymer for realization of effective and comprehensive utilization of mineral resources.(2)Mechanism of polymerization of geopolymer.(3)the combination of preparation of foaming materials and production of geopolymer.Results of the aforesaid research suggest that those two types of tailings can be used to produce geopolymer and that through the control of experimental factors, products with improved performance could be produced. The combination of the reutilization of tailings and the great properties of geopolymer not only addresses environmental pollution and waste of resources, but diversifies the usage of geopolymer materials and turns tailings into a resource.更多还原