高碳含砷难选金矿的选矿工艺研究

发布时间：2018-04-26 12:53

本文选题：难处理金矿 + 含碳含砷　；参考：《广西大学》2015年硕士论文

【摘要】：我国金矿资源储量巨大,但主要以低品位难处理金矿为主。难处理金矿主要包括高碳金矿、微细浸染型金矿、复杂多金属硫化矿型金矿,其中,高碳含砷金矿是极为常见却也极为难处理的金矿之一,目前国内外还没有有效的方法进行处理。本文针对贵州泥堡高碳含砷难选金矿进行试验研究,考察了多种选矿方法对高碳含砷金矿回收的影响,有效解决了高碳和高砷对金回收的影响。贵州泥堡高碳含砷难选金矿原矿石中金品位为3.46g/t,含硫5.55%,含砷0.37%。金的粒度微细并少量嵌布于脉石中,矿石含碳量、含粘土量较高,在浮选过程中易与硫化物一起被浮上来,对金的回收不利。论文通过浮选试验,研究了浮选工艺、磨矿细度、调整剂用量、捕收剂用量等试验条件对精矿指标的影响,得到的结论如下：预先使用摇床重选抛废,尾矿中金品位金金属分布率均偏高。因此对该矿石不宜采用重选预抛废方案。浮选闭路实验结果显示,阶段磨浮流程与一段磨浮流程尾矿金品位指标接近,宜采用一段磨浮流程,且磨矿细度为-200目占95%时效果最佳。且由于原矿中含碳量高、磨矿粒度细,预先脱碳时部分易浮金容易随碳物质上浮,长时间刮泡后仍难以消除碳物质的影响,因此预先脱碳对后续作业的浮选时间及药剂用量降低不明显。浮选药剂上,采用水玻璃1500g/t、硫酸铜400 g/t作为调整剂,丁铵黑药125 g/t、乙黄药240 g/t作为捕收剂,采用一段磨浮/一粗四精三扫的流程,试验指标最佳,为金精矿品位13.71g/t,金回收率78.24%。尾矿再磨再选对提高原矿金回收率意义不大,原因是矿浆粒度变细粘度增加,不利于氰化物溶液对矿石内部渗透和扩散,影响矿石中金与氰化物的接触,使金的浸出率降低。同时,加与不加絮凝剂沉降效果差异不大。因此尾矿进入尾矿库后可进行自然沉降达到沉积目的。硫砷分离试验结果表明,不论是采用浮硫抑砷的方案,还是浮砷抑硫的方案,采用氧化剂法、石灰铵盐法、腐植酸钠法或亚硫酸钠法等不同的方法,不同pH、不同抑制剂、不同磨矿细度等条件均无法实现原矿或是浮选金精矿硫砷的有效分离。
[Abstract]:Gold reserves are huge in China, but mainly low grade refractory gold deposits. Refractory gold deposits mainly include high-carbon gold deposits, micro-disseminated gold deposits and complex polymetallic sulphide gold deposits. Among them, high-carbon arsenic-bearing gold deposits are one of the most common but also extremely difficult to deal with. At present, there is no effective method to deal with it at home and abroad. In this paper, the effects of various processing methods on the recovery of high carbon arsenic gold deposits are investigated, and the effects of high carbon and high arsenic on gold recovery are effectively solved. The gold grade is 3.46 g / t, sulfur 5.55 and arsenic 0.37 in the raw ore of high-carbon and arsenic-refractory gold deposit in Nipu, Guizhou Province. The gold particle size is fine and a little is embedded in the gangue. The ore has high carbon content and clay content. It is easy to be floated together with sulfide in the flotation process, which is disadvantageous to the recovery of gold. In this paper, the effects of flotation process, grinding fineness, dosage of adjuster and collector on the index of concentrate are studied. The distribution rate of gold grade in tailings is higher. Therefore, it is not suitable for the ore to adopt the scheme of gravity separation and pre-dumping. The results of closed circuit flotation experiment show that the gold grade index of tailings in the stage grinding process is close to that in the first stage grinding process, and the best effect is when the grinding fineness is -200 mesh and 95%. Because of the high carbon content and fine grinding granularity in the raw ore, some gold floats easily with the carbon matter in advance decarbonization, and it is difficult to eliminate the influence of carbon matter after long time scouring. Therefore, the advance decarbonization has little effect on the flotation time and dosage of reagents. In flotation reagents, water glass 1500 g / t, copper sulfate 400 g / t as adjuvant, ammonium butyrate 125 g / t, ethyl xanthate 240 g / t as collector, and one stage grinding floatation / one coarse four fine three sweep process were adopted. The test index was the best, the gold concentrate grade was 13.71 g / t, and the gold recovery rate was 78.244.The flotation reagents were as follows: water glass 1500 g / t, copper sulfate 400 g / t, ammonium butyrate 125 g / t, ethyl xanthate 240 g / t as collector. Regrinding and redressing of tailings is of little significance to increase the recovery of gold from raw ore, because the granularity of slurry increases and the viscosity increases, which is not conducive to the penetration and diffusion of cyanide solution into the ore, affects the contact between gold and cyanide in the ore, and reduces the leaching rate of gold. At the same time, the effect of adding flocculant is not different from that without flocculant. Therefore, the tailings can be deposited naturally after entering the tailings reservoir. The results of sulfur and arsenic separation test show that different methods, such as oxidizing agent, lime ammonium salt, sodium humate or sodium sulfite, have different pH and different inhibitors, regardless of the scheme of floating sulfur and arsenic, or the scheme of floating arsenic and sulfur suppression, and the methods of oxidant, lime ammonium salt, sodium humate or sodium sulfite, etc. Different grinding fineness and other conditions can not achieve the effective separation of sulfur and arsenic from ore or flotation gold concentrate.
【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD953

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