本文選題：鐵尾礦　切入點(diǎn)：粉煤灰　出處：《南京理工大學(xué)》2015年碩士論文

【摘要】：鐵尾礦是鐵礦石選取鐵精礦后排放的一種工業(yè)固體廢棄物。隨著鋼鐵工業(yè)的快速發(fā)展,鐵尾礦的排出量越來(lái)越多。對(duì)鐵尾礦的處理已經(jīng)成為礦山企業(yè)的發(fā)展的包袱。利用鐵尾礦制備建筑制品已成為尾礦再利用的研究熱點(diǎn)。本文在系統(tǒng)的分析鐵尾礦的基本特性的基礎(chǔ)上,以鐵尾礦作為主要原料,研究制備燒結(jié)磚和燒脹陶粒的工藝,并對(duì)得到的燒結(jié)磚和陶粒的性能進(jìn)行分析。研究?jī)?nèi)容和結(jié)果如下：1)系統(tǒng)的研究鐵尾礦的基本特性。鐵尾礦的主要礦物組成為斜綠泥石((Mg, Fe)6(Si, Al)4O10(OH) 8)、方解石(CaCO3)、石英(Si02)、赤鐵礦(Fe203)和黃鐵礦(FeS2)等。該尾礦中硅含量偏低,鐵和鈣的含量偏高。鐵尾礦中鐵的含量偏高是由于鐵尾礦含有斜綠泥石、赤鐵礦和黃鐵礦造成的；鈣的含量偏高是由于鐵尾礦含有方解石造成的。鐵尾礦中斜綠泥石的存在使得鐵尾礦具有較好的可塑性。2)以鐵尾礦為主要原料制備燒結(jié)磚,對(duì)得到的尾礦磚相關(guān)性能進(jìn)行測(cè)定。結(jié)果顯示,添加少量的粘土或粉煤灰能有效減小燒結(jié)尾礦磚的體積密度,添加粉煤灰對(duì)體積密度的降低效果更明顯。在燒結(jié)溫度為900℃～1000℃的范圍內(nèi),添加少量粉煤灰的尾礦磚的吸水率在13-18%之間,抗壓強(qiáng)度均大于15MPa,體積密度在1.8 g/cm3-2.0 g/cm3之間,體積收縮在0.5～2.0%之間,質(zhì)量損失在6.0～10.5%之間。燒結(jié)磚的主要的礦物成分為透輝石(Ca(Mg,Al)(Si,Al)2O6)、鈣長(zhǎng)石((Ca,Na)(Si,Al)4O8)、硬石膏(CaSO4)、赤鐵礦(Fe203)和石英(Si02)。這些新生成的礦物相是燒結(jié)強(qiáng)度的主要來(lái)源。通過(guò)對(duì)燒結(jié)尾礦磚微觀(guān)形貌分析可知,添加粉煤灰的燒結(jié)磚的斷面上具有更多的孔隙。3)鐵尾礦中的Si02含量偏低,助熔劑氧化物(尤其是Fe203和CaO)的含量偏高,不能滿(mǎn)足制備燒脹陶粒的化學(xué)組成。通過(guò)添加石英粉和粉煤灰來(lái)調(diào)整配方中Si02、A1203和助熔劑組分三者的配比使混合料滿(mǎn)足制備燒脹陶粒的化學(xué)組成。研究結(jié)果表明,燒結(jié)溫度在1210℃-1230℃范圍內(nèi),保溫時(shí)間在10-20min范圍內(nèi),制備的配比為鐵尾礦占30%,石英粉占10～30%,粉煤灰占40～60%的陶粒均為膨脹陶粒,其膨脹系數(shù)均大于1。所得到的膨脹陶粒的堆積密度均小于0.8g/m3,表觀(guān)密度均小于1.2g/cm3,所得到的陶粒均可稱(chēng)為輕集料。所得到的陶粒的吸水率都很低,這是由于陶粒表面產(chǎn)生一層致密的釉質(zhì)層造成的。對(duì)陶粒進(jìn)行物相分析得到陶粒的主要物相為鈣長(zhǎng)石((Ca,Na)(Si,Al)4O8)、赤鐵礦(Fe203)和石英(Si02)。通過(guò)對(duì)陶粒的SEM形貌分析可知,陶粒內(nèi)部玻璃化現(xiàn)象明顯且內(nèi)部存在獨(dú)立的封閉氣孔。
[Abstract]:Iron tailings are a kind of industrial solid waste discharged from iron ore concentrate. With the rapid development of iron and steel industry, The treatment of iron tailings has become a burden to the development of mining enterprises. The preparation of building products from iron tailings has become a research hotspot of tailings reuse. In this paper, the systematic analysis of iron tailings has been carried out. Based on the basic characteristics of. Using iron tailings as the main raw material, the process of preparing sintered brick and fired expanded ceramsite was studied. The properties of the sintered brick and ceramsite obtained are analyzed. The contents and results of the study are as follows: 1) the basic characteristics of iron tailings are studied systematically. The main mineral composition of iron tailings are clinopyrite, Fe _ (6Si), Al _ (4) O _ (10) OH) _ (8), calcite CaCO _ (3), quartz Si _ (02) ~ (2). Iron ore (Fe203) and pyrite (FeS2). The content of silicon in the tailings is relatively low. The content of iron and calcium in iron tailings is higher than that in iron tailings because iron tailings contain clinachlor hematite and pyrite. The high content of calcium is caused by the iron tailings containing calcite. The existence of clinochlore in the iron tailings makes the iron tailings have good plasticity. 2) using iron tailings as the main raw material to prepare sintered bricks, The results show that adding a small amount of clay or fly ash can effectively reduce the bulk density of sintered tailing bricks. The effect of adding fly ash on the reduction of bulk density is more obvious. In the range of sintering temperature of 900 鈩，

本文編號(hào)：1663771