新喀里多尼亚铬铁砂矿磁化焙烧—磁选工艺的研究
发布时间：2019-06-18 19:20
【摘要】：随着炼铁成本以及对外矿的依赖程度的不断增加,在炼铁过程中使用廉价低品位铁矿石资源显得尤为必要,尤其是对于一些远离港口的钢铁企业。新喀里多尼亚铬铁矿,TFe含量为32.58%,Cr2O3含量为29.46%,不适宜直接应用高炉炼铁和铬铁合金冶炼,以及磁化率比较低,难以通过正常选矿工艺提高铁矿石品位,一直没有得到有效利用。本论文以新喀铬铁砂矿为研究对象,在考查其基础性能的基础上,系统研究了其造球过程、焙烧过程及提高磁化率的工艺方法,为合理利用新喀铬铁砂矿提供理论支持。采用XRD和光学显微镜对新喀铬铁砂矿矿进行了详细研究,发现新喀铬铁砂矿以铬铁矿为主,铬铁矿颗粒多呈粒状分布,结晶程度较好,结构致密,晶粒粗大,气孔较少;铬铁矿中的Cr3+常被Fe3+和Al3+置换呈类质同象结构,Fe2+常被Mg2+所置换,形成镁铬铁矿和铁绿铬矿,导致铬铁选矿分离十分困难。新喀铬铁砂矿原矿粉球团试验研究结果表明:膨润土配比达到2.0%时,生球质量才能满足球团运输和焙烧工艺的要求;适宜的成球条件为:膨润土配2.0%,矿粉粒度-200目80%,生球水分9.8%,煤粉配比2.0%、煤粉粒度-200目80%;适宜的干燥制度为:球团粒度8~15mm,球团矿层厚度200mm,干燥气流速度1.0m/s,干燥温度300℃和干燥时间10min。吊篮磁化焙烧不适用于新喀铬铁砂矿原矿粉球团磁化焙烧工艺;用高温反应管在800℃隔绝空气条件下对新喀铬铁砂矿原矿粉球团进行磁化焙烧40min,磁化焙烧后新喀铬铁砂矿原矿粉球团矿采用一段磨矿、一次粗磁选和一次精选流程可以得到含TFe为58.67%的铁精矿和含Cr2O3为46.96%的铬精矿,TFe和Cr2O3的回收率分别达到77.06%和84.75%,铁精矿和含铬精矿的产率分别为46.23%和53.77%。
[Abstract]:With the increasing cost of ironmaking and the dependence of foreign mines, it is particularly necessary to use cheap and low-grade iron ore resources in the ironmaking process, especially for some steel enterprises far from the port. The content of TFe and Cr2O3 in New Caledonian chromite is 32.58% and 29.46% respectively. It is not suitable for blast furnace ironmaking and ferrochromium alloy smelting directly, and the magnetic susceptibility is relatively low. It is difficult to improve the grade of iron ore by normal mineral processing process, and has not been effectively utilized. In this paper, Xinka Chrome Iron Sand is taken as the research object, and on the basis of investigating its basic properties, the process of pelletizing, roasting and the process of improving magnetic susceptibility are systematically studied, which provides theoretical support for the rational utilization of Xinka Chrome Iron Sand. XRD and optical microscope were used to study the Xinka chromium iron placer in detail. It was found that the Xinka chromium iron placer was mainly chromium iron ore, the chromite particles were mostly distributed in grain shape, the crystallization degree was good, the structure was dense, the grain size was thick, and the porosity was less. The Cr3 in chromite was often replaced by Fe3 and Al3 with homogeneous structure, and Fe2 was often replaced by Mg2, resulting in the formation of magnesia-chromium iron ore and iron green chromium ore, which made it very difficult to separate ferrochromium ore dressing. The experimental results show that the raw pelletizing quality can meet the requirements of pelletizing transportation and roasting process when the ratio of bentonite reaches 2.0%, and the suitable pelletizing conditions are as follows: bentonite 2.0%, ore powder particle size 80%, raw ball moisture 8.8%, pulverized coal ratio 2.0%, pulverized coal particle size 80%, raw ball moisture 9.8%, pulverized coal ratio 2.0%, pulverized coal particle size 80%, bentonite 2.0%, pulverized coal particle size 80%, raw ball moisture 9.8%, pulverized coal particle size 2.0%, pulverized coal particle size 80%. The suitable drying system is as follows: pelletizing particle size 8 鈮，
本文编号：2501725
[Abstract]:With the increasing cost of ironmaking and the dependence of foreign mines, it is particularly necessary to use cheap and low-grade iron ore resources in the ironmaking process, especially for some steel enterprises far from the port. The content of TFe and Cr2O3 in New Caledonian chromite is 32.58% and 29.46% respectively. It is not suitable for blast furnace ironmaking and ferrochromium alloy smelting directly, and the magnetic susceptibility is relatively low. It is difficult to improve the grade of iron ore by normal mineral processing process, and has not been effectively utilized. In this paper, Xinka Chrome Iron Sand is taken as the research object, and on the basis of investigating its basic properties, the process of pelletizing, roasting and the process of improving magnetic susceptibility are systematically studied, which provides theoretical support for the rational utilization of Xinka Chrome Iron Sand. XRD and optical microscope were used to study the Xinka chromium iron placer in detail. It was found that the Xinka chromium iron placer was mainly chromium iron ore, the chromite particles were mostly distributed in grain shape, the crystallization degree was good, the structure was dense, the grain size was thick, and the porosity was less. The Cr3 in chromite was often replaced by Fe3 and Al3 with homogeneous structure, and Fe2 was often replaced by Mg2, resulting in the formation of magnesia-chromium iron ore and iron green chromium ore, which made it very difficult to separate ferrochromium ore dressing. The experimental results show that the raw pelletizing quality can meet the requirements of pelletizing transportation and roasting process when the ratio of bentonite reaches 2.0%, and the suitable pelletizing conditions are as follows: bentonite 2.0%, ore powder particle size 80%, raw ball moisture 8.8%, pulverized coal ratio 2.0%, pulverized coal particle size 80%, raw ball moisture 9.8%, pulverized coal ratio 2.0%, pulverized coal particle size 80%, bentonite 2.0%, pulverized coal particle size 80%, raw ball moisture 9.8%, pulverized coal particle size 2.0%, pulverized coal particle size 80%. The suitable drying system is as follows: pelletizing particle size 8 鈮，
本文编号：2501725
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