难选铁闪锌矿多金属矿石的浮选试验与机理探讨

【作者】 谢贤；

【导师】 童雄；

【作者基本信息】 昆明理工大学 ， 矿物加工工程， 2011， 博士

【摘要】 本研究课题得到了2008年度国家发改委重大产业技术开发专项“难选锌锡铜铟多金属硫化矿综合回收共伴生金属的选矿关键技术”项目的资助,目的是高效回收铜、锌以及共伴生的铟、银和镉等稀贵金属。我国含铁闪锌矿的复杂、难选多金属矿石资源十分丰富,仅云南文山都龙矿区就蕴藏金属：锌240万吨、铟3779吨、锡26万吨、铜7.8万吨,其中铟和锡储量分别居全国第一和第三位、锌储量居云南第三位,锌、铟、锡、铜金属的潜在经济价值超过1100亿元；矿石中的铜矿物、锌矿物、锡石和硫化铁等矿物嵌布粒度细,共生关系密切,而且锌矿物为高铁或者超高铁闪锌矿,铁含量达到20%左右,该多金属矿曾经一度被判为不能经济有效利用的“呆”矿。由于铜、锌、硫矿物嵌布紧密,导致铜-锌分离困难、铜精矿中金属互含严重；此外,锌矿物由于铁含量高,容易被氧化,导致其可浮性差,选别难度大。采用常规活化剂硫酸铜和高碱浮选工艺,锌精矿品位低、回收率不高,特别是共伴生在锌矿物中的稀贵金属铟、银和镉等回收率低,资源浪费严重。因此,对这类复杂难处理多金属矿石中有价金属的分离研究具有重要的理论研究意义和实际价值。目前,这类难处理多金属矿石的利用,主要存在以下技术问题：①铜锌矿物嵌布粒度细,铜-锌不能实现有效地分离,特别是铜精矿中锌含量高达10-18%,严重影响了铜精矿的质量,也造成了锌矿物的损失；②常规活化剂硫酸铜不能有效选择性活化高铁闪锌矿,导致锌精矿中硫化铁矿物含量高,锌品位低,仅有41%-45%；③高碱条件下锌-硫分离,不仅抑制硫化铁矿物,锌等主金属以及共伴生的稀贵金属也会受到一定的影响,导致回收率不高；此外,高碱条件也非常不利于后续酸性环境下的脱硫作业,影响硫-锡、铁-硫的高效分离,严重影响锡、铁的回收。本论文以文山都龙含铁闪锌矿多金属矿为研究对象,进行了原矿的工艺矿物学研究,进行了实际矿石的铜-锌和锌-硫分离的实验室试验和工业试验,考察了超高铁闪锌矿、高铁闪锌矿、低铁闪锌矿和磁黄铁矿纯矿物在不同药剂体系下的浮选行为,研究了X-41对铁闪锌矿纯矿物的选择性活化和对磁黄铁矿纯矿物的选择性抑制,验证了X-41对实际矿石中铁闪锌矿的活化,进行了高铁闪锌矿相关的吸附量和动电位测试,探讨了X-41选择性活化与抑制的机理,取得了以下主要成果：(1)铁闪锌矿纯矿物浮选结果表明,无论对于超高铁闪锌矿、高铁闪锌矿还是低铁闪锌矿,活化剂的活化效果顺序均为X-41>CuSO4>PbNO3>NH4Cl。(2)实际矿石试验结果表明,优化工艺-药剂制度的闭路试验指标明显优于原有的现场工艺-药剂制度的指标。铜精矿品位和回收率分别提高7.93和11.92个百分点,银品位和回收率分别提高118g/t和7.47个百分点；锌精矿品位和回收率分别提高4.56和3.26个百分点,铟的品位和回收率分别提高了74.9g/t和4.2个百分点。(3)工业试验结果表明,采用X-41的闭路试验指标明显优于硫酸铜的指标,低碱即pH=9左右的条件下,铜精矿品位和回收率分别提高2.12和10.29个百分点,银品位和回收率分别提高59.3g/t和8.32个百分点；锌精矿品位和回收率分别提高1.16和2.35个百分点,铟品位和回收率分别提高9.2g/t和2.6个百分点,银品位和回收率分别提高2.84g/t和4.69个百分点,镉品位和回收率分别提高50g/t和3.25个百分点,每年的综合经济效益为5205.25万元。更多还原

【Abstract】 This research work was supported by the project of Key Technique for Comprehensive Utilization of Associated metals (In, Ag, Ca, et al.) from Refractory Zn-Sn-Cu-In Multi-metal Sulfide Ore, from the Major Industry Technology Develops Special of 2008 of the National Development and Reform Commission.There is an abundant refractory iron-bearing marmatite reserve in China. Wenshan Dulong ore of Yunnan, take is as example.possesses 2,400,000 tons of Zn,37,790,000 tons of In,260,000 tons of Sn and 78,000 tons of Cu, in which the reserves of In and Sn rank the first and the third in China, respectively; however, the iron grades in zinc minerals reaches as high as 20% Fe. The economic value of these valuable minerals, including Copper, Zinc, Indium, Tin and iron sulfide, et al., reaches as high as 110 billion RMB. These copper, zinc, tin and iron sulfide minerals embedded in such an orebody have ever been believed worthless, due to their fine and complex associations with each other. Such a dilemma results in the difficulty that the separation between Copper and Zinc is ineffective, and the zinc minerals can not be easily floated, as a result of its high iron content. With the conventional copper sulphate as activator and the high-alkali flotation process, the grade of zinc concentrate is very low with poor recovery and the recoveries of other associated minerals such as indium, silver and cadmium in zinc minerals are even much lower than that of zinc mineral, resulting in the huge waste of such a resource. Therefore, the research on effective separation of the valuable minerals from this refractory multi-metal sulfide ore has significant theoretical and practical values.There nowadays exit the following problems for the effective processing of this refractory multi-metal sulfide ore, they are:(1) copper can not be effectively separated from zinc minerals, because of their fine association with each other, leading to the high zinc content (10-18%) in copper concentrate and the loss of zinc minerals; (2) high iron-bearing sphalerite can not be effectively floated with the conventional copper sulphate as activator, and the zinc concentrate has only a 41-45% Zn grade with high impurity of iron sulfide; (3) iron sulfide minerals can not be effectively depressed under a high-alkali condition during the zinc-sulfide separation process, resulting in the low recoveries of zinc and other associated minerals. In addition, the high-alkali condition is also not favorable for the desulphurization process followed, and the separations for S-Sn and for Fe-S can not be effectively achieved, significantly deteriorating the recovery of Sn and Fe.The multi-metal sphalerite with high irons was used for the present work; its process mineralogy was analyzed, and the practical Cu-Zinc and Zinc-S separations are carried out at a pilot- and full- scales, respectively. The behaviors of sphalerites with super-high, high and low irons and of the pyrrhotite during their flotations with different reagent combinations are also investigated; the selective activation of pure sphalerite with iron and the depression of pure pyrrhotite were both tested with X-41, and its activation effect was further confirmed on a practical sphalerite. Moreover, the adsorption and potentiodynamic tests closely related with a high iron sphalerite were made; and the selective activation and depression mechanisms of X-41 were also discussed, with the main conclusions as follows:(1) The results of flotation results for pure iron sphalerite indicate that the activation ability follows the order X-41>CuSO4>PbNO3>NH4Cl, whether for high or low iron sphalerites;(2) The results of flotation results for practical iron sphalerite indicate that, while the process and reagents combination were optimum, the flotation results of the pilot-scale in laboratory obviously precedes that of the full-scale one on spot. Compared to the full-scale, the pilot-scale achieved a 7.93% Cu grade higher and 11.92% Cu recovery higher copper concentrate, with its Ag grade and recovery 118 g/t and 7.47% higher, respectively; and achieved a 4.56% Zn grade higher and 3.26% Zn recovery higher zinc concentrate, with its In grade and recovery 74.9 g/t and 4.20% higher respectively.(3) The results of industrial test indicates that the experimental performance of X-41 is significantly superior to that of copper sulphate; under a low-alkali condition, i.e., at a pH of 9, the X-41 obtained a copper concentrate assaying 2.12% Cu higher with 10.29% recovery higher, with its Ag grade and recovery 59.30 g/t and 8.32% higher respectively, in comparison with those of copper sulphate; and obtained a 1.16% Zn grade higher and 2.35% Zn recovery higher zinc concentrate, with its In grade 9.20 g/t higher and recovery 2.60% higher and its Ag grade 2.84% higher and recovery 4.69% higher and its Ca grade 50.0 g/t higher and recovery 3.25% higher, respectively. The use of X-41 produces an overall economic value reaching as high as 52.0525 million RMB per year.更多还原