Mineralogical characterization of silver flotation concentrates made from zinc neutral leach residues

Silver flotation concentrates prepared from high-silver (1480 ppm Ag) and low-silver (300 ppm Ag) neutral leach residues have been examined mineralogically to determine the phases present and to elucidate the behavior of silver during zinc processing. The flotation concentrates consist principally of sphalerite although lesser amounts of zinc ferrite and PbSO₄, as well as traces of other phases, also are present. In the high-silver flotation concentrate, silver occurs mostly as Ag₂S or (Ag, Cu)₂S rims on sphalerite although (Ag, Cu)₂S inclusions within sphalerite also are present. Trace amounts of a Cu-Ag-S-Cl phase are present on rare copper oxide grains, and this silver-bearing phase may be a fine mixture of Ag₂S, AgCl, and Cu₂S. In the low-silver flotation concentrate, silver occurs mostly as Ag₂S although traces of silver-bearing CuS and Cu₂S also are present. The Ag₂S occurs as <1 μm particles disseminated in elemental sulfur-silica gel patches, as discontinuous rims or isolated patches on sphalerite grains, and as tiny free particles. Silver chloride was not detected. These studies suggest that silver dissolves during neutral leaching and subsequently reacts with sphalerite or other sulfides to form silver sulfide.     

Extraction of nickel from ferromolybdenum leach residues

Abstract

The extraction of nickel from ferromolybdenum leach residues by sulphation roasting, water leaching and iron removal from subsequent nickel leach solutions was studied. Sulphation roasting and water leaching promote the reaction between sulphuric acid and the residue and decrease the silicon dissolution. Over 90% of Ni was leached. Ferric ions in the solution could be effectively removed as jarosite and ferric hydroxide. The recovery of nickel reached 88·3% under sulphation roasting with the sulphuric acid quality of 1472 kg t^?1 leach residue at 280°C for 4 h followed by iron removal with addition of 0·5 g NaClO₃, 6 g Na₂SO₄ and 10 g CaO/100 mL solution at 95°C for 2·5 h, while the concentration of iron in solution reduced to 0·38 from 56·6 g/L^?1.

On a étudié l’extraction du nickel à partir de résidu de lessivage de ferromolybdène par grillage sulfateur, lessivage à l’eau et enlèvement du fer des solutions obtenues de lessivage de nickel. Le grillage sulfateur et le lessivage à l’eau favorisent la réaction entre l’acide s ulfurique et le résidu et diminuent la dissolution de la silice. On a lessivé plus de 90% du Ni. On pouvait enlever efficacement de la solution les ions ferriques sous forme de jarosite et d’hydroxyde ferrique. La récupération du nickel atteignait 88·3% au moyen du grillage sulfateur, avec 1472 kg d’acide sulfurique par tonne de résidu de lessivage à 280°C pendant 4 h, suivi par l’enlèvement du fer avec l’addition de 0·5 g de NaClO₃, 6 g de Na₂SO₄ et 10 g de CaO par 100 mL de solution à 95°C pendant 2·5 h, la concentration du fer dans la solution étant réduite de 56·6 à 0·38 g L^?1.     

Precipitate flotation of nickel from acidic laterite leach solutions

Precipitate flotation has been used to preferentially concentrate nickel over iron dissolved in solutions obtained by sulfuric acid leaching of a selectively reduced laterite. Leach solutions, containing about 3 g/L nickel, 0.5 g/L ferrous, 0.5 g/L magnesium, were neutralized using sodium carbonate to give mixed precipitates of a basic nickel carbonate and mainly non-carbonate iron compounds. At the optimum pH of 8.2, stage additions of sodium oleate and Dowfroth 250 (Dow Chemical Company product) totalling 0.07 g/g total nickel and 0.08 g/L solution, respectively, gave flotation recoveries of 93% nickel and 36% iron into concentrates analyzing 41% nickel and 2.8% iron. By neutralizing with sodium hydroxide instead of sodium carbonate, non-selective flotation of nickel and iron is obtained with increased consumption of collector and frother.     

用溶剂萃取法从氧化锌矿浸出渣中回收锌

低品位氧化锌矿酸浸后,浸出渣中夹带3%以上的锌,采用水洗-P204萃取可回收酸浸渣中的水溶性锌,得到的反萃液经过净化后可电积沉锌。该工艺可与湿法炼锌工艺相结合处理低品位氧化锌矿。     

用溶剂萃取法从氧化锌矿浸出渣中回收锌

低品位氧化锌矿酸浸后，浸出渣中夹带3％以上的锌，采用水洗-P204萃取可回收酸浸渣中的水溶性锌，得到的反萃液经过净化后可电积沉锌。该工艺可与湿法炼锌工艺相结合处理低品位氧化锌矿。     

黑龙江伊春某含银铅锌矿石工艺矿物学研究

对黑龙江伊春某含银多金属半氧化矿石进行工艺矿物学详细测定与研究,目的是查清矿石性质、目的矿物种类、嵌存关系、粒度分布、单体解离等特征,为其多金属选别工艺的确定提供可靠依据。依据该矿石目的矿物的工艺特征,确定了原矿优先选银（铅）—银尾矿浮锌—锌尾矿磁选铁的工艺流程。通过对尾矿产品中目的矿物流失状态的分析表明：浮选、磁选铅、锌、银、铁的选别效果达到了预定指标;这也证明了该工艺流程选择的合理性、正确性,达到了理想的回收效果。     

XRF法测定铅锌混合矿中银

本文用X -射线荧光光谱法快速定量分析铅锌混合矿中银 ,通过对共存元素间基体吸收 -增强效应的校正 ,有效地解决了铅锌混合矿中铅基体变化时 ,对银的干扰问题 ,所得结果满足铅锌选矿冶炼工艺生产控制要求。     

湿法炼锌高酸浸出渣浮选银选矿废水回收锌及循环利用工艺分析

对湿法炼锌高酸浸出渣浮选银后的选矿废水回收锌及循环再利用工艺进行了探讨.从经济、环保、投资等几方面对工艺进行对比优选,分析了选矿废水中选矿药剂、杂质元素、固体悬浮物的影响,探讨了工艺的可行性、影响因素及应对措施.     

锌浸出渣火法处理银挥发初探

简要叙述了湿法炼锌过程中银的行为,介绍了锌浸出渣火法处理的方式及效果,分析表明,锌浸出渣火法烟化处理时,铅、锌、银及稀散金属挥发较理想,并且烟化炉渣为一般固体废物,较彻底地解决了环保问题。     

从高酸浸出锌渣中回收银研究

针对某锌冶炼厂高酸浸出渣含银高的特点,采用硫酸化焙烧—水浸脱锌铁—氯化浸银—冷却结晶PbCl2—铅片置换沉银工艺,对高酸浸出锌渣进行了回收银研究。结果表明,锌和铁的浸出率分别达到92.66%和94.67%,浸出液返回炼锌主流程生产电锌;银和铅的浸出率分别达到94.17%和97.89%;用铅片置换得到粗银粉,银置换率达到99%以上。     

从某尾矿中浮选回收银试验研究

由于是库存老尾矿,银矿物在一定程度上被氧化和钝化。在浮选试验中对活化剂、捕收荆、精选条件等进行了研究。结果表明,在捕收剂黄药70g／t、活化剂硫酸铜500g/t、精选加入1kg／t水玻璃条件下,可取得精矿银品位2053．90g／t、回收率92．85％的试验指标。     

Mathematical modeling of the zinc pressure leach process

A comprehensive mathematical model is described for the zinc pressure leaching process. Generic kinetic expressions were derived from experimental data found in the literature for the following reaction events: (1) dissolution of marmatite, (Zn,Fe)S, (2) oxidation of ferrous to ferric, and (3) precipitation of lead jarosite. Aqueous solution properties, oxygen solubility, density, enthalpy, and vapor pressure, were correlated with solution composition and temperature. Subsequently, a kineticsbased model for simultaneous sulfide dissolution and iron precipitation in a multistage, three-phase reactor was developed. The population balance method was used for sulfide mineral material balances, and apparent equilibrium was assumed for iron precipitation. A gas-phase material balance was included, which allows for prediction of oxygen utilization. The model was solve for a particular operation of the Cominco Ltd. (Trail, BC) autoclave, and prediction results were shown to be in very good comparison with actual plant performance.     

冀东磁铁精矿球团焙烧机理的研究

研究了焙烧温度、时间等因素对冀东磁铁精矿粉球团焙烧质量的影响.当预热温度超过1 000 ℃时,颗粒表面生成液相,造成球团氧化不完全;当焙烧温度超过1 275 ℃时,球团中的脉石大量同化,产生大量硅酸盐液相,降低成品球强度.冀东磁铁精矿球团最佳焙烧工艺为:氧化温度为900～950 ℃,氧化时间不低于20 min,焙烧温度为1 250～1 275 ℃,焙烧时间不低于20 min.     

浮选金精矿微生物氧化渣提金工艺试验研究

针对某含砷、含硫微细包裹类型难处理金矿石提金工艺进行了研究。该矿石常规氰化金浸出率仅为12.54%。通过对其浮选金精矿进行生物氧化预处理,并对生物氧化渣提金工艺的氰化法、氯化法、硫脲法进行了浸金对比试验。其结果表明,氯化法浸金效果最好,金浸出率可达94.73%,指标优于其他两种工艺。     

竖炉球团配用不同进口精矿的试验研究

介绍了马钢配用7种不同进口精矿进行造球和工业投笼试验的情况.综合经济效益分析结果,得出以下结论:巴A与MBR 2种精矿为较适宜的进口高品位造球原料,其经济效益可观,其次为巴C精矿,随后是弗布卡、弗乔,巴B、沙马可精矿.     

铜钼混合精矿分离浮选工业试验研究

介绍了国外从斑岩铜矿中回收钼的主要矿山和进行铜、钼浮选分离的主要方法。乌努格吐山大型斑岩铜钼矿选矿通过小型试验和前期工业试验,找出了工业生产中存在铜钼混合精矿脱水脱药不理想、陶瓷过滤机无法过滤-325目含量占88%铜精矿的问题。最后经过尝试,用原有陶瓷过滤机过滤混合精矿,脱水脱药效果明显,并使用加压过滤机过滤铜精矿,解决了陶瓷过滤机无法过滤细粒级铜精矿的难题。选矿工艺流程经改造后,试生产连续产出了合格的钼精矿,钼精矿品位为48%、含铜1.2%。同时,对铜、钼分离工艺中的一些主要问题进行了分析讨论。