| Iron ore tailing is a kind of castoff from iron ore mill run plant. As a long time accumulation and with a loss of efficient utilization, the huge piles of iron ore tailings occupy a great quantity of mountain land and cultivated land, even cause ruinous damage to eco-environment. Iron ore tailings dam break disasters often reported in the public media remind us it has a great threat to our life and property. As a result, in order to achieve the efficient utilization of iron ore tailing, the study of making iron ore tailing into high value added products is more and more recognized by researchers. The main purpose is to study the technology of making architectural surface decorating materials from iron ore tailings powder, so as to make theoretical preparation for resource utilization of iron ore tailings.We researched into Anshan style iron ore tailing and maked it into architectural surface decorating materials with sintering additives added in the raw material. First of all, we determined the mineral constitutions and chemical composition of the iron ore tailing. The analysis of the additives added in iron ore tailing to form the raw material is carried out. We disscussed the burnability and sintering mechanism of the raw material. Based on the above work, we studied hot-press sintering method and non-press sintering method in making iron ore tailing powder into architectural surface decorating materials. Lastly, we contrasted the properties of the sintered material with that of the marble and granite. The main research work shows below:(1) The main mineral composition contained in Anshan style iron ore tailing are quartz, calcite, chlorite, hornblende et.al. While the chemical compositions which compose those minerals are SiO2, Al2O3, Fe2O3, MgO, FeO. We discussed chemical reaction, sintering driving force, sintering mechanism of the sintering progress. The components in the iron ore tailing powder meet the need of sintering architectural surface decorating material.(2) Hot-press sintering method in the preparation of decorating material using iron ore tailing is studied. The raw materials used in experiment are the mixture of iron ore tailing powder and some additives in determinate proportions. The experimental conditions and the content of additives are studied by orthogonal experimental method. Hot press experiments are carried out accoding to the designed orthogonal experimental table. Furthermore, the properties of the as-sintered samples are tested.(3) On the basis of analysis of the sintering mechanism and experiment of hot-press sintering, the non-press sintering architectural decorating material made from the mixture of iron ore tailing powder and glass powder is explored. Differential thermal analysis and thermal gravity analysis are introduced to analyze the thermal performance of the raw material. This reveals the principle of exothermic and endothermic behavior and gravity change. Depending on this principle, we can determine the needed sintering temperature and heating rate during the experiment progress. The micro-structure and crystalline phase are observed by scanning electron microscope and X-ray diffraction techniques.We can make good raw material by adding appropriate additives in the iron ore tailing powder. We analyzed the characteristics of two sintering methods, non-press sintering and hot press sintering, and disscussed the feasibility of making sintered iron ore tailing material by these two methods; The properties of one of the best samples are:compression strength-106MPa, tensile strength-6MPa, Bending strength-23MPa, water absorption capability-0, acid resistance-0, alkali resistance-0. The best condition of making hot-press material using iron ore tailing are: compositions and proportions (iron ore tailing powder-50%, Al2O3-5%, MgO-11%, CaO-15%, Na2CO3-7%, K2CO3-2%, B2O3-4%, S-1%), sintering temperature-950℃, press-15MPa,sintering time-45mins; We tested the properties of the samples and found that the material whose raw material contents 22%wt glass powder in it possessing the best performance, besides the sintering temperature is about 1130℃.
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