【作者】 胡显智；

【导师】 张文彬；

【作者基本信息】 昆明理工大学 ， 矿物加工工程， 2002， 博士

【摘要】 对于以严重蚀变的蛇纹石为主要脉石的镍、铜硫化矿或贵金属硫化矿，仅通过浮选等物理选矿难以获得易于冶炼的低镁优质精矿。这类矿石的选矿降镁难题至今仍未获得突破。本研究提出了酸浸降镁以解决上述高镁矿石选矿降镁难题的新方案。即用稀酸浸出的方法将蛇纹石中的MgO溶解以大幅降低最终精矿中MgO含量从而获得低镁优质精矿；同时，对进入浸出液的Mg、Fe等综合回收产出铁红、轻质氧化镁等产品。该方案不但能攻克高镁矿石选矿降镁难题，而且能提高矿石的资源综合利用率，产生明显的经济效益。 本文对上述方案的可行性进行了理论分析与探讨，用热力学原理计算、分析研究了低酸浸出蛇纹石、各种含铁矿物及铜镍硫化矿物与稀酸的反应活性。结果表明，蛇纹石易与酸反应，其MgO可被稀酸完全浸出；含铁矿物中，铁的碳酸盐、硅酸盐、FeO等也将与MgO同时被浸出，磁黄铁矿（FeS）将部分被浸出，而Fe₂O₃、黄铁矿（FeS₂）则不会被浸出。黄铜矿、镍黄铁矿不易与稀酸反应。 金宝山低品位铂钯矿是我国已探明的最大的独立铂族金属资源。但由于矿石所具有的“贫、细、杂、难”的特点，给选矿和铂族元素提取带来了巨大的困难，铂钯回收率偏低，尤其是浮选精矿含镁过高，于后续冶炼十分不利，一直阻碍着该资源的开发利用。 在理论研究基础上，进行了低浓度硫酸浸出金宝山铂钯矿的试验研究，系统研究了酸浓度、浸出温度、浸出液固比、原矿细度等单因素条件与原矿中Mg、Fe浸出率间的关系，同时进行了浸出时间、酸浓度与Mg、Fe浸出率关系的正交实验。结果表明，上述因素均与Mg、Fe浸出率成正比关系；而酸浓度比浸出时间对Hg、FQ浸出率的影响显著得多。用25％左右浓度的硫酸，在常压下即可将金宝山铂钯矿中绝大部分MgO浸出。由于矿石经酸浸后其有用矿物的浮选活性大大提高，浸渣用简单流程少量药剂就可浮选出低镁优质铂钯精矿（MgO含量＜3％），且Pt、Pd、Cu、Ni回收率较原矿浮选明显提高。这表明， 酸浸一浸渣浮选是解决金宝山铂钮矿选矿降镁难题的一条有效途径， 解决了该主贵资源的开发利用中的一个关键性难题。 酸浸过程进入浸出液中的ag、ne可综合回收产出铁红、轻质氧 化镁等产品。本研究中，用 F e’”水解法分离浸出液中的 M g、F e，滤饼 经烘干、暇烧制备铁红：滤液再次净化后用纯碱将屿’”沉淀为碱式碳 酸镁，碱式碳酸镁经烘干、懒烧制备轻质氧化镁，经权威机构检测， 所制轻质氧化镁达国标优等品级。 采用酸浸一浸渣浮选并对进入浸出液中的Mg、Fe综合回收产出 铁红、轻质氧化镁等产品的新工艺开发利用金宝山铂铅矿，不但能很 好解决其选矿降镁难题；同时还能大大提高其资源利用率及其开发利 用的经济效益：浸渣中有用矿物的品位较原矿明显提高，因此采用该 工艺可处理更低品位的原矿，可扩大金宝山铂铅矿的可采储量；浸渣 浮选尾矿中 h。含量高达70％以上，且粒度细微，可进一步开发制备 多孔硅如白碳黑等产品，因此有望实现整个工艺无尾矿产出，最终实 现该矿资源的完全综合利用。 硫酸法钛白生产中要产生大量废酸，每生产1吨钛白粉要产生浓 度为 20％左右的废硫酸 8～10吨。如何治理、综合利用如此大量的废 酸己成为硫酸法钛白生产企业迫切需要解决的重大难题。 利用攀钢（集团）钛业公司钛白生产中产生的高浓度废酸（20％ 左右）作为浸出金宝山铂铅矿的浸取剂的试验研究结果表明，用钛白 废酸作为金宝山铂铂矿的浸出用酸是完全可行的，这不但可以解决该 I 矿选矿降镁难题，进一步降低酸浸成本：而且也为硫酸法钛白生产中 产牛的大量高浓度废酸找到了一条综合利用的有效途径。由于废酸中 含有大量的Fe’”，酸浸液中Fe””浓度高，用水解法分离Mg、Fe，过滤 困难。研究中采用黄铰铁矾法分离浸出液中的Mg、Fe，结果表明， 该法很有效，沉淀易于过滤。所得黄镣铁矾沉淀可用于制备铁红：除 铁余液经再次净化后可用较纯碱更廉价的混沉镁剂（NH．HO 与 NHHCO的混合溶液）沉淀其中的Mg，所得碱式碳酸镁经洗涤、烘干、 嫩烧制备轻质氧化镁，原矿中Mg（）总收率达7O％以上，所得轻质氧化 11 3 镁经检测达一等品级。回收Mg的余液还可产出硫酸镀。整?更多还原

【Abstract】 If the main gangue in nickel-copper sulfide ores or precious metals sulfide ores is serpentine transformed from primary silicate minerals, it is difficult to get a high quality concentrate with lower MgO content that is suitable for smelting by physical mineral processing only such as floatation. This thesis put forward a new method to process this kind of ores. The MgO of serpentine is dissolved by diluted sulfuric acid so as to reduce MgO content of the final concentrate greatly. The ions of magnesium and iron dissolved in leaching solution can be utilized to produce iron oxide red and light magnesium oxide comprehensively. The new method not only can overcome the difficult problem about MgO’s reducing of the ores with high MgO content by flotation, but also can raise the utilization ratio of the ores greatly. Therefore, treating the ores with the new method can lead obvious economic benefit.This thesis has studied the feasibility about the new method .The thermodynamic calculation and analysis for the reactions of serpentine and all of minerals containing Fe in sulfide ores as well as copper-nickel sulfide minerals with diluted sulfuric acid have been studied. The results showed that serpentine can react with diluted sulfuric acid easily and the MgO can be dissolved completely. Carbonate and silicate of iron as well as FeO in the minerals containing Fe also would be dissolved with leaching of MgO. Pyrrhotite (FeS) would be dissolved partly, but pyrite (FeS2) and iron oxide (FezOs) could not be dissolved with leaching of MgO. Chalcopyrite and pentlandite can also not react with diluted sulfuric acid.Jinbaoshan Platinum-Palladium Mine is so far the China’s largest independent platinum group metals ore deposit. However, the platinum-palladium grade in the ore is rather low, not only the dissemination particle size of valuable minerals in the ore is extremely fine, but also the composition of the ore is very complex, and the serpentine content is high to 75%, so mineral processing of the ore is very difficult. The MgO content of floatation concentrate of the ore is difficult to reduce to below 20%. It is also difficult to smelt for such a concentrate with so high MgO content. For this reason, there is still no effective method to utilize the mineral resources at the present. Based on the theoretical studies, it has been investigated systematically that Jinbaoshan platinum-palladium ore was leached by diluted sulfuric acid. The relationships between leaching rate of Mg or Fe and consistency of sulfuric acid and temperature and liquid/solid ratio as well as particle size of the sample have been tested simultaneously. The full factorial experiment of the relationship between the consistency of sulfuric acid, leaching time and leaching rate of Mg has also beentested. The test results showed that: all of the single factors mentioned above are in direct proportion to leaching rate of Mg or Fe; for leaching rate of Mg or Fe, the influence of consistency of sulfuric acid is more remarkable than that of leaching time. The most MgO in Jinbaoshan platinum-palladium ore could be dissolved by diluted sulfuric acid solution with the consistency of 25%. Because the process characteristics of the residue are improved obviously, the high quality platinum-palladium concentrate with very low MgO content ( <3%)can be obtained from the residue by floatation using simple processing and small amount floating reagent, the recovery of Pt or Pd or Cu or Ni raised obviously. Therefore, the new method processing Jinbaoshan platinum-palladium ore by leaching and residue’s flotation is very effective.The ions of magnesium and iron dissolved in leaching solution can be utilized to produce iron oxide red and light magnesium oxide comprehensively. Magnesium and iron in the leaching solution can be separated by hydrolysis method of Fe +, the iron oxide red can be produced from the hydrolyte by drying and calcining, the filter solution (MgSO4 solution) can be precipitated into magnesium carbonate (basic) with sodium carbonate and then更多还原