鄂西某高磷鲕状赤铁矿提铁降磷试验研究

发布时间：2018-08-09 12:26

【摘要】：高磷鲕状赤铁矿是我国主要的复杂难选铁矿石之一,矿石储量较大,占铁矿资源储量的11%左右。我国现已探明的高磷鲕状赤铁矿石储量约37.2亿吨,可勘探新资源量预计达上百亿吨。高磷鲕状赤铁矿具有复杂的化学成分以及独特的结构构造,富集难度极大,其选别是选矿界公认的难题。本论文首先通过XRF、XRD、物相分析、岩矿鉴定等手段对原矿进行工艺矿物学研究,得知该矿石中铁品位为43.13%,有害元素磷的含量高达0.86%,主要脉石矿物Si O2含量为17.20%。该矿石是典型的高磷鲕状赤铁矿,本试验针对该矿石嵌布关系复杂、嵌布粒度极细且有害杂质磷含量高等特征,围绕“提铁降磷”,进行了工艺流程探索性试验研究。首先采用高梯度磁选处理原矿。在粗磨条件下,采用一粗一精一扫高梯度磁选流程进行选别,确定最佳磨矿细度为-0.074mm含量占65%,最佳磁场强度为粗选0.8T、精选0.5T、扫选0.9T。粗磨选别后,将中矿(精选尾矿和扫选精矿)再磨后进行一粗一精磁选,确定最佳再磨细度为-0.074mm含量占90%,最佳磁场强度为粗选0.8T、精选0.4T。进行高梯度磁选闭路试验,将中矿再磨精选尾矿返回再磨球磨机,获得磁选精矿铁品位为53.06%,相对于原矿提高9.94个百分点,回收率为78.53%,磁选尾矿产率为36.18%、铁品位为25.59%。可见高梯度磁选精矿指标较好,且抛尾能力较强。以磁选精矿为处理对象,采用反浮选进行提铁降杂。试验研究表明,磁选精矿细磨—直接反浮选效果不好,引入脱泥流程后反浮选效果明显增强。确定最佳磨矿细度为-0.038mm含量占95%,选择性絮凝脱泥最佳条件为分散剂用量12kg/t、矿浆p H值11、苛性淀粉用量0.3kg/t,反浮粗选最佳条件为矿浆p H值11、苛性淀粉用量1.0kg/t、氯化钙用量0.12kg/t、捕收剂PL用量0.8kg/t、浮选时间4min。通过细磨—选择性絮凝脱泥—阴离子反浮选闭路试验,反浮选采用一粗二精一扫流程,中矿合并返回粗选,获得反浮选精矿铁品位为56.75%,相对于磁选精矿提高了3.63个百分点,整体回收率为72.26%,取得了良好的提铁降杂效果。以反浮选精矿为处理对象的酸浸脱磷试验表明,最佳条件为硫酸用量100kg/t、保铁剂LX用量2kg/t、反应时间2h、浸出浓度40%、搅拌速度200r/min。通过酸浸试验,浸出精矿磷含量降至0.10%,同时铁品位为59.12%、整体回收率为69.32%,可见保铁降磷效果较好。对各阶段试验的最佳工艺流程及条件进行组合,采用高梯度磁选—选择性絮凝脱泥—阴离子反浮选—酸浸联合工艺流程处理原矿,获得最终精矿铁品位为59.20%,相对原矿提高16.07个百分点,铁回收率为69.96%,磷含量降至0.10%,脱磷率为94.07%,取得了良好的提铁降磷效果,该联合工艺流程为该类矿石的选别利用提供了一定的借鉴意义。Zeta电位研究分析表明,石英被Ca2+活化后,与捕收剂PL发生化学吸附,导致矿物表明疏水性被上浮;表面吸附试验表明,Ca2+活化后,当p H达到11时石英表面捕收剂吸附量最大。
[Abstract]:High phosphorus oolitic hematite is one of the main complex refractory iron ores in China. The ore reserves are larger and account for about 11% of the reserves of iron ore. The reserves of high phosphorus oolitic hematite are about 37.2 million tons, and the amount of new exploration resources is estimated to be up to 100 million tons. High phosphorus oolitic hematite has complex chemical composition and unique structure. Structure is very difficult to enrich, and its selection is a difficult problem in mineral processing industry. In this paper, the process mineralogy of raw ore was studied by means of XRF, XRD, phase analysis and rock mineral identification. It was found that the iron grade of the ore is 43.13%, the phosphorus content of the harmful elements is as high as 0.86%, and the Si O2 content of the main gangue mineral is 17.20%. the typical high Phosphorus oolitic hematite, in this experiment, is characterized by complex arrangement of the ore, very fine granularity and high phosphorus content and high content of harmful impurities. The experimental study on the process flow is carried out around "iron lifting and reducing phosphorus". First, high gradient magnetic separation is used to deal with the raw ore. Under coarse grinding conditions, a coarse and one precision sweep high gradient magnetic separation process is used. No, it is determined that the best grinding fineness is -0.074mm content 65%, the best magnetic field strength is coarse selection 0.8T, the selection of 0.5T and the selection of 0.9T. coarse grinding, then the medium ore (selected tailings and scavenging concentrates) is regrinded for a coarse and one fine magnetic separation, and the optimum re grinding fineness is -0.074mm content, the optimum magnetic field strength is coarse 0.8T, and the selected 0.4T. is carried out high ladder. The secondary ore regrinding tailings are returned to the regrinding ball mill by the closed circuit magnetic separation test. The iron grade of the magnetic concentrate is 53.06%. Compared with the original ore, the recovery rate is 9.94 percentage points, the recovery rate is 78.53%, the magnetic separation tail mineral rate is 36.18%, the iron grade is 25.59%. and the high gradient magnetic separation concentrate is better, and the finishing capacity is stronger. The magnetic concentrate is treated as the treatment. The experimental study shows that the effect of fine grinding direct reverse flotation of magnetic separation concentrate is not good, and the effect of reverse flotation is obviously enhanced after the introduction of degash process. The optimum grinding fineness is -0.038mm 95%, the optimum condition for selective flocculation and degash is 12kg/t, P H value of pulp and 0. of caustic starch. 3kg/t, the optimum conditions for the reverse flotation are p H value 11, the dosage of caustic starch 1.0kg/t, the dosage of calcium chloride 0.12kg/t, the PL amount 0.8kg/t of the collector, the flotation time 4min. through the fine grinding selective flocculation deliming and anionic reverse flotation closed circuit test, the reverse flotation uses a coarse two fine sweep process, the middling mine is merged back to coarse selection, and the reverse flotation concentrate iron is obtained. The grade is 56.75%, which is 3.63 percentage points higher than the magnetic concentrate, and the overall recovery rate is 72.26%. The effect of iron reduction is good. The acid leaching dephosphorization test of the reverse flotation concentrate shows that the optimum condition is 100kg/t, 2kg/t, 2h, 40% and 200r/min.. In the acid leaching test, the phosphorus content of the leaching concentrate is reduced to 0.10%, the iron grade is 59.12% and the overall recovery rate is 69.32%. It can be seen that the effect of iron and phosphorus reduction is better. The optimum process and conditions of the experiment are combined, and the high gradient magnetic separation selective flocculation desliming, the reverse flotation and acid leaching process is used to treat the raw ore. The iron grade of final concentrate is 59.20%, 16.07 percentage points higher than that of raw ore, 69.96% of iron recovery, 0.10% of phosphorus and 94.07% for dephosphorization. The effect of iron and phosphorus reduction is obtained. The combined process provides a certain reference for the selection of the ore by the.Zeta potential study and analysis shows that the quartz is live by Ca2+. After chemical adsorption, the chemical adsorption of the collector PL leads to the flotation of the hydrophobicity, and the surface adsorption test shows that when the Ca2+ is activated, the adsorption capacity of the quartz collector is the largest when the P H reaches 11.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD951

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