醇类起泡剂对细粒级尾矿浮选回收铜的影响及机理分析

选用非极性基结构不同的醇类起泡剂MIBC和松醇油作为起泡剂回收江西某铜矿矿石中的有价金属铜。通过浮选试验和泡沫时间-体积试验,测定铜的品位、回收率及泡沫体积随时间的变化情况,研究醇类起泡剂对细粒级尾矿浮选回收铜的影响及作用机理。结果表明,MIBC起泡能力强,增大了气泡与目标矿物的碰撞黏附概率;当MIBC用量为30 g/t时,一次粗选铜回收率可达30.19%;在相同浓度条件下,MIBC产生的泡沫体积大,增大了与脉石矿物的碰撞概率,因此精矿品位低。     

应用组合起泡剂优化黑、白钨混合浮选

针对湖南某钨选厂使用杂醇类起泡剂BK205所产生的泡沫小、性脆、泡沫层薄等不利于二次浮选的特点,采用BK205与新型醚类起泡剂CU组合使用以便实现矿石中钨矿物的高效回收。结果表明,在采用BK205与新型醚类起泡剂CU组合质量比为3∶1、先BK205后CU的加药方式下,小型闭路试验得到精矿WO3品位为30.13%,回收率为78.98%。工业试验表明,组合起泡剂不仅改善浮选泡沫,减少药剂用量,降低药剂成本,而且能获得比原起泡剂更好的工业指标,使钨矿物得到更高效的回收。     

纤维素醚调整剂对MIBC起泡剂泡沫性能影响研究

浮选泡沫的性质对矿物的浮选效果具有重要影响。本文以甲基异丁基甲醇(MIBC)为起泡剂,研究羟丙甲基纤维素(HPMC)、羧甲基纤维素(CMC)和3-氯-2-羟丙基三甲基氯化铵纤维素醚三种泡沫调整剂对起泡剂MIBC泡沫的稳定性、表面张力、气泡尺寸和数量等特性的影响。结果表明,随着泡沫调整剂浓度的增加,表面张力降低,泡沫稳定性增强,HPMC对泡沫稳定性的增强效果最好。通过自建图像法测量系统、采用Image-Pro-Plus软件测定、分析气泡数量和尺寸,试验结果显示,泡沫调整剂的加入减少了气泡的数量、减小了泡沫尺寸、增大颗粒与气泡的碰撞概率。透射电镜表明,在纤维状纤维素醚分子链上吸附了MIBC颗粒。黄铁矿纯矿物的浮选实验结果表明,泡沫调整剂的加入提高了黄铁矿纯矿物的回收率。     

福建丁家山铅锌硫化矿组合起泡剂优化浮选

福建丁家山铅锌硫化矿铅品位为1.07%,锌品位为4.02%,具有一定回收价值。用组合起泡剂代替松醇油作为浮选起泡剂以在原有工艺基础上提高精矿品位。结果表明,使用MIBC∶松醇油=3∶2的组合起泡剂,可以使浮选泡沫具有更为适宜的尺寸、黏度和泡沫层厚度,在保证回收率的基础上,提高精矿品位。经过工业试验,得到铅品位46.61%、回收率为84.07%的铅精矿,锌品位51.45%、回收率为88.57%的锌精矿,与单独以松醇油作为起泡剂相比,原矿资源得到更好地回收。     

组合起泡剂优化铅锌硫化矿浮选试验研究

福建某铅锌硫化矿中铅品位为1.07％,锌品位为4.02％,具有一定回收价值。为了在原有工艺基础上提高精矿品位,尝试使用组合起泡剂代替松醇油作为浮选起泡剂,结果表明,使用MIBC：松醇油=3:2的组合起泡剂,可以使浮选泡沫具有更为适宜的尺寸、粘度和泡沫层厚度,在保证回收率的基础上,提高了精矿品位。经过工业试验,得到铅品位为46.61%、回收率为84.07%的铅精矿,锌品位为51.45%、回收率为88.57%的锌精矿。相较于单独以松醇油作为起泡剂,原矿得到了更好地回收。     

带有弱捕收性能的起泡剂的应用

如果保证浮选过程的选择性不是首要任务，那么可以在浮选中应用选择性较差的起泡剂。以提高矿物的回收率。通过改变烃链长度和引入电子供体原子来增大起泡剂疏水一亲脂平衡值。可以降低其表面活性。增强其捕收力。在铜钼矿石浮选中应用ΦPHM型亲脂性高的起泡剂既可代替选择性高的MIBC起泡剂，也可与主捕收剂和主起泡剂混合应用，提高精矿回收率和品位。减少捕收剂和起泡剂的用量。     

浮选过程中高岭石夹带行为研究

为了探索浮选过程中高岭石的夹带规律,通过设计高岭石单矿物浮选试验,研究了高岭石粒度、矿浆质量浓度、起泡剂用量和捕收剂用量对浮选过程中高岭石回收率、水回收率和高岭石夹带率的影响。研究发现:高岭石的粒度与起泡剂仲辛醇的用量是影响高岭石夹带行为的主要因素,高岭石粒度越小,起泡剂用量越大,高岭石的夹带率就越大;矿浆中高岭石的质量浓度对高岭石的夹带率影响不大,随着高岭石质量浓度的增大,其夹带率基本保持不变,只会增大水回收率;随着捕收剂煤油用量的增大,高岭石回收率的增加并不明显。     

某含碳铅锌硫化矿选矿试验研究

某铅锌矿含铅1.68%、锌11.50%、碳3.68%，属含碳铅锌硫化矿石。矿石中金属矿物主要是闪锌矿、方铅矿、黄铁矿和磁黄铁矿，脉石矿物以石英、正长石和白云母为主。矿石中的碳主要以游离碳和有机碳的形式存在，如何消除碳对铅锌浮选过程的影响已成为该资源开发利用的关键。根据该矿石性质，采用高效脱碳剂BK208实现了预先脱碳的目的，减少了碳对后续铅锌浮选的影响。通过“预先脱碳-铅锌顺序优先浮选-铅锌粗精矿再磨精选”的工艺流程，成功实现了铅锌的高效回收，闭路试验获得了铅品位59.65%、锌品位6.85%、铅回收率78.59%的铅精矿，以及锌品位48.69%、铅品位0.81%、锌回收率89.28%的锌精矿，取得了良好的浮选指标。在含碳铅锌硫化矿选矿过程中，消除碳质脉石对铅锌回收的不利影响，对提高选矿指标具有重要的意义。     

起泡剂浓度对不同粒度瘦煤浮选效果的影响

为定量分析起泡剂用量对不同粒度分布瘦煤的浮选效果影响规律,选择MIBC为起泡剂,利用XDF-1L实验室浮选机,揭示了不同粒度分布瘦煤在不同起泡剂浓度条件下浮选效果的变化规律。结果得出不同粒度煤样的浮选效果随起泡剂浓度增加的变化规律,研究结果为煤炭浮选控制脉石矿物的泡沫夹带和提高煤浮选效果提供理论参考。     

广西某低品位钨钼矿石选矿试验研究

广西某低品位钨钼矿石中主要有用矿物为辉钼矿和白钨矿,还有少量黄铁矿、磁黄铁矿,脉石矿物主要为辉石、石榴石、石英等。矿石经钼硫优先混合浮选—混合精矿再磨钼硫分离—混浮尾矿再选钨闭路试验,获得了钼品位为50.386%、回收率为91.17%的钼精矿,硫品位为36.782%、回收率为56.43%的硫精矿,WO3品位为60.366%、回收率为68.94%的钨精矿。     

Flotation frother mixtures: Decoupling the sub-processes of froth stability,froth recovery and entrainment

The flotation process consists of two distinct phases: the pulp and froth phase. One of the main roles of the froth phase is to create a suitable environment for the separation of floatable, valuable minerals from non-selectively recovered, entrained gangue minerals. As a result the froth phase plays a significant role in the metallurgical performance of industrial flotation cells. Froth stability is important for the recovery of valuable minerals. However, a stable froth may contribute to increased entrainment and, consequently, a lower grade.This study compares the effect of frother mixtures with that of their single component frothers on the froth stability, froth recovery and entrainment of a platinum-bearing UG2 ore using polyglycol and alcohol frothers. The study showed that frother mixtures resulted in a greater froth stability than either of their component frothers. The increased froth stability was reflected in increased froth recoveries and greater overall recoveries. However, the important aspect in the use of frother blends was that they altered the froth structure and resulted in a lower degree of entrainment. This, together with the increased recovery, resulted in higher grades of valuable mineral recovered to the concentrate when using the frother mixtures.     

The effect of frother blends on the flotation performance of selected PGM bearing ores

Concentrators processing PGM bearing ores make use of polysaccharide depressants to reduce the recovery of the undesired naturally floatable gangue minerals, mainly silicates, present in the ore. Recent work has shown that high depressant dosages can completely depress naturally floatable gangue and thus prevent it from reporting to the concentrate. These high depressant dosages can, however, have a negative effect on the recovery of valuable minerals present in the ore by reducing the stability of the froth. In order to counterbalance the effects of depressant addition, frothers are added. It is, however, preferable to maintain independent control over bubble size and froth stability which is difficult to achieve with only one frother. An alternative strategy is to use a blend of frothers, e.g. a weaker frother in combination with a stronger frother. Such a system allows an additional degree of freedom: changing the ratio of the two frothers provides more independent control of bubble size and froth stability. This study demonstrates through the use of batch flotation tests how blending low molecular weight alcohols with commercially available frothers impacts the solids and water recovery, as well as the valuable mineral recovery and concentrate grade in different PGM ores. Higher water and solids recoveries together with higher valuable mineral recoveries (>90% copper and >70% nickel) were obtained from tests using frother blends.     

新型起泡剂FG25在硫化铜矿和铅锌矿浮选中的应用研究

对自主研发的新型起泡剂FG25进行了起泡性能研究, 结果表明, 当FG25浓度大于0.02 g/L时, 其起泡能力明显优于松醇油和MIBC, 而泡沫的稳定性介于松醇油和MIBC之间, 是一种性能优良的浮选起泡剂。FG25和松醇油作起泡剂的浮选对比实验结果表明, 对于某硫化铜矿, FG25与松醇油相比可使铜回收率提高1.60个百分点, 品位提高5.71个百分点;对于某铅锌矿, FG25与松醇油相比可使铅回收率提高0.65个百分点, 锌回收率提高0.40个百分点。     

Rougher flotation of copper sulphide ore using biosolids and humic acids

In the quest of new, less hazardous, and more ambient-friendly froth flotation reagents, the use of biosolids or humic acids as both collector and frother for the concentration of copper sulphide ores was investigated. Rougher flotation tests were conducted in Denver cells on a laboratory scale, and metallurgical indicators such as copper recovery, copper concentrate grade, and concentration and enrichment ratios were compared with those obtained under similar conditions but using conventional collectors and frothers for the industrial flotation of copper sulphide ores. With a dosage of 10% (w/w) biosolids, copper recovery and grade were 26% and 0.81%, respectively. The copper recovery and grade obtained with 1.5% (w/w) salt of humic acids were 29.7% and 3.5%, respectively. A significantly higher copper recovery (65.1%) was obtained with conventional industrial collectors and frothers, but the grade was also low (3.1% Cu). With the same dosage of humic substances, humic acid show that the flotation rate constant was significantly higher (0.2 min⁻¹) than that obtained with the same dosage of biosolids (0.09 min⁻¹). These results indicate that humic acids have more affinity than biosolids for copper-containing mineral species, and also show that biosolids and humic acids could be used as both collector and frother in the sulphide mineral concentration process by froth flotation. Because the distribution of iron in the concentrate obtained with biosolids is highest, these materials seem to have more affinity for pyrite.     

起泡剂对凝灰岩型氧化铜矿中微细矿泥可浮性的影响

通过凝灰岩型氧化铜矿中微细矿泥(-20μm)上浮率试验、润湿接触角和泡沫水回收率测定,考察矿泥天然可浮性、泡沫水回收率、起泡剂种类及用量对矿泥可浮性的影响。结果表明,矿泥天然疏水性低,起泡剂不能增加矿泥的疏水性,但起泡剂增加了泡沫水回收率,泡沫水夹带是导致矿泥上浮的主要原因。不同种类起泡剂对微细矿泥的上浮率有不同的影响,影响程度按二乙二醇丁醚,MIBC、松醇油依次降低。为减少凝灰岩型氧化铜矿浮选中矿泥的影响,选择合适的起泡剂和降低起泡剂用量是必要的。     

Non-ionic polyethylene oxide frothers in graphite flotation

The Kringel Mine (Woxna Graphite AB) in Hälsingland, Sweden, is one of the largest graphite flake deposits in the world with over 10 million tonnes of ore suitable for open cast mining. Concentration of crystalline graphite is carried out through a combination of flotation, gravimetric and magnetic separation. In the present study, several polyethylene oxide type frothers were evaluated as flotation frothers for the graphic ore. From (a) laboratory dynamic and equilibrium surface tension experiments, (b) froth equilibrium height measurements, (c) bench scale flotation tests and (d) plant trials, it was shown that a polyoxypropylene glycol butyl ether (MW 300 and HLB 6.5) was the most effective frother for the graphic particles. The frother was found to produce closed packed, molecular cohesive films at the air/solution interface showing high elasticity at low concentrations, which appeared to prevent bubble coalescence. The plant has been successfully using this frother as a replacement for MIBC since July 1997.     

Towards a new process for the flotation of quartz

Results obtained from flotation experiments performed on three different quartz concentrates demonstrate that quartz can be floated in diluted solutions of hydrofluoric acid (HF) simply by the aid of frothers alone. The recovery was found to be highly dependent on the choice of frother and strongly positively correlated with the concentration of both frother and HF, as well as with the HF conditioning time. Experiments using HNO₃ instead of HF showed no flotation of quartz. Of the five different frothers tested, Brij 58 was found to produce the highest recovery. Good recoveries were also obtained for Dowfroth 400 and Flotanol C07, whereas Dowfroth 200 and MIBC failed to float any quartz. From experiments in which a given feed material were tested at two different particle size distributions it was found that highest recoveries were obtained for the finer feed. Chemical analysis of the floated products showed that these were significantly purer than their corresponding feed materials, and that most of the contaminating elements were concentrated in the sink fraction that remained in the cell. Contact angle measurements corresponded well with flotation recoveries.     

Case studies on the performance and characterisation of the froth phase in industrial flotation circuits

This paper deals with two separate case studies investigating the froth phase performance and characterisation of two industrial rougher/scavenger flotation circuits. Froth phase performance was quantified using a mass balance approach to estimate froth zone recovery. Measured characteristics of the froth phase included frother solution concentration determined by gas chromatography, and the time taken for an equilibrium froth sample to decay to one-half of its original froth height. The latter measurement is referred to as the ‘froth half-life’ and is strongly linked to froth stability. Special methods and techniques developed to preserve frother in solution and to measure froth half-life are briefly described. The frother type in the first case study was a mixture of straight and branched alcohols, whilst the frother type in the second case study was a mixture of alcohols, aldehydes and triethoxybutane. The first case study focussed on a flotation circuit treating a low grade ore containing only a small fraction of floatable copper sulphide minerals, while the second case study focussed on a flotation circuit treating a higher grade complex sulphide ore containing significant quantities of chalcopyrite, galena, sphalerite and pyrite.It was found that froth zone recovery of valuable mineral generally decreased down-the-bank of the two industrial rougher/scavenger circuits. Moreover, decreases in froth zone recovery significantly limit the overall cell recovery of valuable mineral achievable from the plant scavenger cells. However, the decrease in froth zone recovery could not be linked to the removal of frother from the pulp solution to the concentrate product in the preceding rougher flotation stages. Measurements of residual frother in solution suggested that, approximately, only 5–10% of the added frother was removed into the rougher/scavenger concentrate, with the remainder appearing in the scavenger tailings. This finding suggested there was apparently adequate frother in solution in the scavenger stages.There was, however, a correlation to the froth half-life, with the froth half-life also generally decreasing down-the-bank. A simple, empirical model, based on the froth half-life and froth residence time of gas, is proposed here to predict froth zone recovery. Further, it is proposed that the froth stability, as measured by the froth half-life, is strongly linked to the presence of particles in the froth, with poorly mineralised scavenger froth characterised by a short half-life and, potentially, a low froth zone recovery. The importance of particles on froth stability was confirmed in separately conducted laboratory experiments. These experiments also demonstrated the wide variation in froth stability behaviour between different frother types.     

The effect of increased frother dosage on froth stability at high depressant dosages

High energy costs required to smelt low grade concentrates could be alleviated by the production of high grade concentrates. Obtaining maximum PGM recovery by the use of high dosages of polysaccharide depressants may be problematic in that a significant decrease in the stability of the froth, particularly with CMC, results. These highly unstable froths may result in restricted mass pulls and decreased valuable mineral recovery. There are a number of ways of counteracting unstable froths, such as increasing airflow rate, reducing froth height or increasing frother dosage. Although necessary to maximise PGM recovery, all of these are likely to lead to increased water recovery and dilution of the concentrate by entrained material. This work examines the effect of increasing frother dosage on the recovery of sulphide minerals and floatable gangue from a Merensky ore at varying dosages of guar gum and CMC, as well as on the recovery of entrained gangue and its dependence on the physical nature of the flotation pulp.     

Assessment of the floatability of chalcopyrite,molybdenite and pyrite using biosolids and their main components as collectors for greening the froth flotation of copper sulphide ores

Biosolids and representative compounds of their main components – humic acids, sugars, and proteins – have been tested as possible environment-friendly collectors and frothers for the flotation of copper sulphide ores. The floatability of chalcopyrite and molybdenite – both valuable sulphide minerals present in these ores – as well as non-valuable pyrite was assessed through Hallimond tube flotation tests. Humic acids exhibit similar collector ability for chalcopyrite and molybdenite as that of a commercial collector (Aero 6697 promoter). Biosolids show more affinity for pyrite. The copper recovery (85.9%) and copper grade (6.7%) of a rougher concentrate obtained using humic acids as main collector for the flotation of a copper sulphide ore from Chile, were very similar to those of a copper concentrate produced by froth flotation under the same conditions with a xanthate type commercial collector. This new and feasible end-use of biosolids and humic acids should be new environment-friendly organic froth flotation agents for greening the concentration of copper sulphide ore. Now, further research is needed in order to scale current laboratory assays to operational mining scales to determine efficiencies to industrial scale.