Rationale of Timed-Release Analysis and the Improvement of Flotation Experiment

The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward a proposal to improve this test method by adding a new test step of scavenging flotation and using optimum test conditions varied with different fine coals instead of the given ones settled by the TRA norm. Comparison between test results of the two methods of TRA shows that the improved method is very good.

Elucidating the enhancement of kaolinite flotation by iron content through density functional theory: A study on sodium oleate adsorption efficiency

This study delves into the intricate relationship between iron(Fe)content in kaolinite and its impact on the adsorption behavior of sodium oleate.The effects of different iron concentrations on adsorption energy,hydrogen bond kinetics and adsorption efficiency were studied through simulation and experimental verification.The results show that the presence of iron in the kaolinite structure significantly improves the adsorption capacity of sodium oleate.Kaolinite samples with high iron content have better adsorption properties,lower adsorption energy levels and shorter and stronger hydrogen bonds than pure kaolinite.The optimal concentration of oleic acid ions for achieving maximum adsorption efficiency was identified as 1.2 mmol/L across different kaolinite samples.At this concentration,the adsorption rates and capacities reach their peak,with Fe-enriched kaolinite samples exhibiting notably higher flotation recovery rates.This optimal concentration represents a balance between sufficient oleic acid ion availability for surface interactions and the prevention of self-aggregation phenomena that could hinder adsorption.This study offers promising avenues for optimizing the flotation process in mineral processing applications.

Flotation tree analysis for recovery of sillimanite from red sediments

In this paper an attempt is made to recover sillimanite by flotation tree analysis process and conventional flotation process from non magnetic fraction of red sediments.The experimental results of both the processes are presented.The data reveal that the deslimed sample contains 33.2%(by weight) total heavy minerals and out of which the sillimanite mineral content is 3.6%(by weight).It is observed that flotation tree analysis needs 10 cells to get five output products and where as conventional flotation process needs 15 cells to recover similar grade of five output products.Thus,flotation tree analysis is not only economic process but also efficient process(to say efficient process,the tree analysis product should be higher grade).

Correlation Analysis of Control Parameters of Flotation Process

The dosage of gold-antimony flotation process of 5 main drugs,including Copper Sulfate,Lead Nitrate,Yellow Medicine,No.2 Oil,Black Medicine,with corresponding visual features of foam images,including Stability,Gray Scale,Mean R,Mean G,Mean B,Mean Average,Dimension and Degree Variance,were recorded.Parameter correlation analysis showed that the correlation among Copper Sulfate,Yellow Medicine,Black Medicine,as well as the correlation among Gray Scale,Mean R,Mean G,Mean B,is strong,and the correlation among Dimension,Gray Scale,Mean R,Mean G,Mean B,as well as the correlation between Stability and each dosing parameter,is week.It also indicated a feasible way to decrease the complexity of flotation control system by reducing some parameters.

Selective flotation separation of andalusite and quartz and its mechanism

The separation of andalusite and quartz was investigated in the sodium oleate flotation system, and its mechanism was studied by solution chemical calculation, zeta-potential tests, Fourier transform infrared spectroscopic(FTIR), and X-ray photoelectron spectroscopic(XPS). The flotation tests results show that FeCl3·6H2O has a strong activation effect on andalusite and quartz and citric acid has a strong inhibitory effect on activated quartz, thus increasing the floatability difference between quartz and andalusite when the pulp p H is approximately 8. The FTIR, Zeta potential, and XPS analyses combined with the chemical calculation of flotation reagent solutions demonstrate that Fe forms hydroxide precipitates on the surface of andalusite and quartz and that oleate anions and metal ions adsorb onto the surface of the minerals. The elements Al and Fe can be chemically reacted. The anions in citric acid have different degrees of dissolution of Fe on the andalusite and quartz surfaces, thereby selectively eliminating the activation of the elemental Fe on andalusite and quartz and increasing the floatability of andalusite, leading to a better separation effect between andalusite and quartz.

Process mineralogy as a key factor affecting the flotation kinetics of copper sulfide minerals

The aim of this study is to apply process mineralogy as a practical tool for further understanding and predicting the flotation kinetics of the copper sulfide minerals. The minerals' composition and association, grain distribution, and liberation within the ore samples were analyzed in the feed, concentrate, and the tailings of the flotation processes with two pulp densities of 25 wt% and 30 wt%. The major copper-bearing minerals identified by microscopic analysis of the concentrate samples included chalcopyrite(56.2 wt%), chalcocite(29.1 wt%),covellite(6.4 wt%), and bornite(4.7 wt%). Pyrite was the main sulfide gangue mineral(3.6 wt%) in the concentrates. A 95% degree of liberation with d_(80) > 80 μm was obtained for chalcopyrite as the main copper mineral in the ore sample. The recovery rate and the grade in the concentrates were enhanced with increasing chalcopyrite particle size. Chalcopyrite particles with a d_(80) of approximately 100 μm were recovered at the early stages of the flotation process. The kinetic studies showed that the kinetic second-order rectangular distribution model perfectly fit the flotation test data. Characterization of the kinetic parameters indicated that the optimum granulation distribution range for achieving a maximum flotation rate for chalcopyrite particles was between the sizes 50 and 55 μm.

Correspondence of bubble size and frother partitioning in flotation

The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst.This causes the increased concentration in the froth compared to the bulk concentration,named as frother partitioning.Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known.There currently exists no such a topic aiming to link these two key parameters.To fill this vacancy,the correspondence between bubble size and frother partitioning was examined.Bubble size was measured by sampling-for-imaging(SFI)technique.Using total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was determined.Measurements have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the froth.The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and D32.The CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction.

Effect of deep oxidation of chalcopyrite on surface properties and flotation performance

In this study, chalcopyrite was oxidized in hydrogen peroxide(H_(2)O_(2)) solutions of different concentrations to simulate different degrees of oxidation in real ores, and the effects of H_(2)O_(2) treatment on chalcopyrite surface properties and flotation performance were investigated by surface analysis techniques and floatation experiments, which implied the reason for the poor grade and recovery of oxidized chalcopyrite concentrate in the production process of the ore. Flotation results showed that when the concentration of H_(2)O_(2) increased from 0%(by weight) to 5%, the flotation recovery of chalcopyrite decreased sharply.However, with increasing H_(2)O_(2) concentration from 5% to 30%, chalcopyrite recovery improved relatively to different degrees with different collector concentrations. Analyses of X-ray photoelectron spectroscopy(XPS) and inductively coupled plasma-atomic optical emission spectrophotometry(ICP-OES) results indicated that the pretreatment with H_(2)O_(2) caused that hydrophilic substance formed on chalcopyrite surface with the dissolution of copper ions, and the dissolution amount of copper increased with the increase of H_(2)O_(2) concentration. UV–visible spectrophotometer and Fourier transform infrared spectrum(FTIR) studies indicated that the pretreatment of chalcopyrite with H_(2)O_(2) had little effect on the adsorption amount of potassium butyl xanthate(PBX) on chalcopyrite surface. However, due to the dissolution of copper ions, PBX interacted with chalcopyrite mainly as buthyl dixanthogen(BX)_(2).

Pico–nano bubble column flotation using static mixer-venturi tube for Pittsburgh No.8 coal seam

The flotation process is a particle-hydrophobic surface-based separation technique. To improve the essential flotation steps of collision and attachment probabilities, and reduce the step of detachment probabilities between air bubbles and hydrophobic particles, a selectively designed cavitation venturi tube combined with a static mixer can be used to generate very high numbers of pico and nano bubbles in a flotation column. Fully embraced by those high numbers of tiny bubbles, hydrophobic particles readily attract the tiny bubbles to their surfaces. The results of column flotation of Pittsburgh No. 8 seam coal are obtained in a 5.08 cm ID and 162 cm height flotation column equipped with a static mixer and cavitation venturi tube, using kerosene as collector and MIBC as frother. Design of the experimental procedure is combined with a statistical two-stepwise analysis to determine the optimal operating conditions for maximum recovery at a specified grade. The effect of independent variables on the responses has been explained. Combustible material recovery of 85–90% at clean coal product of 10–11% ash is obtained from feed of 29.6% ash, with a much-reduced amount of frother and collector than that used in conventional column flotation. The column flotation process utilizing pico and nano bubbles can also be extended to the lower limit and upper limit of particle size ranges, minus 75 lm and 300–600 lm, respectively, for better recovery.

Kinetic approach to the study of froth flotation applied to a lepidolite ore

The number of published studies related to the optimization of lithium extraction from low-grade ores has increased as the demand for lithium has grown. However, no study related to the kinetics of the concentration stage of lithium-containing minerals by froth flotation has yet been reported. To establish a factorial design of batch flotation experiments, we conducted a set of kinetic tests to determine the most selective alternative collector, define a range of pulp p H values, and estimate a near-optimum flotation time. Both collectors（Aeromine 3000 C and Armeen 12D） provided the required flotation selectivity, although this selectivity was lost in the case of pulp p H values outside the range between 2 and 4. Cumulative mineral recovery curves were used to adjust a classical kinetic model that was modified with a non-negative parameter representing a delay time. The computation of the near-optimum flotation time as the maximizer of a separation efficiency（SE） function must be performed with caution. We instead propose to define the near-optimum flotation time as the time interval required to achieve 95%–99% of the maximum value of the SE function.

Study on the Axial Dispersion of Liquid in Column Flotation

An experimental study on the axial dispersion of liquid was carried out in a 0.382-m-ID flotation column packed with different structured packings or free of packings. The correlations of axial Peclet numbers with the liquid and gas superficial Reynolds numbers were developed for various packings. Among the packings tested, it is found that in the column packed with 250Y or 350Y packings the axial dispersion is the lowest. The addition of frother can decrease the axial dispersion. By the simulation analysis of the one-dimension dispersion model of packed flotation column, it is found that small axial dispersion, high collection rate constant and low axial liquid velocity can increase the collection zone recovery.

The Effects of Water Recycling on Flotation at a North American Concentrator—Part 1

Water chemistry and its impact on mineral processing operations are not well understood and often not adequately monitored. CanmetMINING, as part of its water management research program, has been involved in a project initiated to identify opportunities for improving water recovery, water treatment, and recycling in the mining and mineral processing operations. One of the main objectives of this work is to evaluate and assess water chemistry and identify factors that impact mineral recovery, concentrate grade, and metal extraction efficiencies in order to understand and mitigate negative impacts of water recycling and improve process efficiency. In collaboration with a North American concentrator, CanmetMINING has been involved in assessing the water chemistry in the mill and evaluating water recycling options for select process streams to reduce fresh water intake and maximize recycling. The overall goal of the project is to investigate options for water recycling (increase the thickener overflow recirculation from thickener overflow tank) without affecting nickel and copper metallurgy. The results of the sampling campaigns showed that the water chemistry of the streams was fairly consistent throughout the year with no significant seasonal variations. The laboratory tests illustrated that when higher quantities of thickener overflow from thickener overflow were used, the nickel + copper grade versus nickel recovery curves shifted towards lower values. These observations were observed for the plant water samples obtained in April, June and August 2019.

低品位胶磷矿重选中矿浮选试验研究及重浮联合分选工艺

低品位胶磷矿经强化离心重选抛尾后得到了部分合格精矿,但其重选中矿的量仍然较大、品位仍然较高。为更充分地回收磷矿,基于对重选中矿的元素组成、矿物组成和嵌布情况分析,进行了浮选试验,并通过FTIR分析了反浮选的机理,最后将强化离心重选与浮选研究结果加以整合,确定采用重浮联合工艺。研究结果表明:重选中矿的P_(2)O_(5)品位为17.12%,主要矿物为磷灰石、白云石和石英,其细粒级解离相对较充分,但粗粒级(>0.074mm)仍有部分未解离。对重选中矿进行磨矿后浮选,正浮选中随着碳酸钠用量的增加,精矿品位逐渐上升、产率逐渐下降,随着捕收剂ZF-1用量的增加,精矿产率不断上升、品位不断下降,两者最佳用量分别为3.0,1.5kg/t,此时精矿产率和品位分别为67.81%和21.41%;反浮选中随着硫酸用量的增加,精矿产率不断下降,品位则先升高而后趋于稳定,随着捕收剂ZF-2用量的增加,精矿产率不断下降,但下降速度逐渐减小,精矿品位则先升高而后趋于平稳,两者最佳用量分别为5,0.9kg/t,此时精矿产率和品位分别为60.49%和26.97%。FTIR测试发现,最佳试验条件下ZF-2与胶磷矿未发生CO_(3)^(2-)明显吸附,而在白云石表面则发生了化学吸附,并对白云石本身的起到了良好的遮蔽效果,因而起到了反浮选脱除碳酸盐类矿物的目的。将重选与浮选整合,得到重浮联合的最终精矿和最终尾矿,产率和品位分别为39.06%和25.12%,60.94%和8.51%,整体效果良好。

鳞片石墨粗磨粗选阶段杂质分布规律研究

为探究石墨在粗磨粗选过程中杂质分布规律,降低石墨粗精矿中杂质含量,以黑龙江萝北某石墨矿为研究对象,通过磨浮单因素条件试验和显微镜下矿物解离度分析,考察磨矿细度、捕收剂用量及起泡剂用量对石墨粗磨粗选阶段杂质迁移规律的影响。结果表明,磨矿细度增加,石墨单体与脉石有效分离,能减少杂质脉石进入粗精矿,杂质回收率从21.14%降至12.70%;捕收剂用量增加,脉石杂质回收率由4.51%升至10.73%,石墨粗精矿品位降低;起泡剂用量增加能够提高气泡的机械强度,防止气泡兼并,提高石墨的回收率,但起泡剂用量增加,夹带作用增强,细粒杂质脉石的回收率由3.8%升至6%。本研究结果为降低粗磨粗选阶段石墨粗精矿中的杂质含量提供了依据。

难浮煤泥浮选流程的试验研究

针对入浮煤泥难浮的问题,以山西矿区1/3焦煤煤泥为研究对象,基于可浮性分析结果对该煤泥进行了单元浮选试验、精选降灰试验,以及精选联合尾煤扫选试验。可浮性试验结果表明:煤泥中的主要密度级为1.4~1.8g/cm3中间密度级,产率为62.87%、灰分为18.24%,中煤含量大,浮选选择性差;<0.045mm粒级产率为32.67%,细泥物导致精煤受到污染,致使煤泥整体可浮性较差。在药剂用量为1.0kg/t,药剂用量比(煤油∶仲辛醇)为4的条件下进行单元浮选试验,结果表明,一次粗选不能达到要求的产品灰分。精选降灰分步释放浮选试验得到产率为25.01%、灰分为11.57%的精煤,产率为52.70%的中煤,精煤灰分满足指标要求,但一次精选尾煤产率过高,中煤未进行有效分选。采用一粗一精二扫流程试验得到产率为47.64%、灰分为11.75%的精煤,产率为35.65%、灰分为23.64%的中煤和灰分为80.21%的尾煤,精煤、中煤、尾煤指标均达到要求,较一粗二精二扫流程精煤产率提高了16.80个百分点,中煤分选充分,产率降低了17.17个百分点。因此,在难浮煤泥的浮选过程中,适当增加扫选工艺可提高各产品的分选效率,且一粗一精二扫试验可将粗选尾煤中的中煤成分分离,在保证获得高灰尾煤的前提下,降低了精煤受到细泥污染而影响分选效率的可能性。

跨航道海底油品管道覆盖层设计与施工

某新建油码头为离岸式,采用跨航道埋入式海管接岸,海管需回填覆盖层加以防护。基于DNV系列标准,对管线进行屈曲、沉降、抗浮和撞击吸能分析,确定覆盖层厚度、构成和回填料参数,确保管线施工不被损坏,在位运行稳定。阐述海底管道覆盖层施工工艺比选、具体施工方法和实施效果。实践证明,该海底管道覆盖层设计合理,所选施工方法适用,可供类似工程参考。

充气式微泡浮选机的浮选槽流场研究

为进一步探究充气式微泡浮选机在运行过程中的更多细节特征,以某型工业充气式微泡浮选机为研究对象,在建立仿真分析模型的基础上,应用Fluent流场数值模拟计算软件,分析浮选机运行过程中的液相速度、气相速度和湍流三方面的典型特征,并探究引起上述特征的主要原因,以此总结充气式微泡浮选机的浮选槽流场特征,并提出后续的可能优化路径,以供参考。

新型捕收剂MC在微细粒难选金矿浮选中的应用

河南省某微细粒难选金矿存在金回收率低的问题,急需对原工艺进行优化。烷基胺可在催化剂作用下与反应剂进行主反应,再进行分离、交连、螯合及乳化反应,从而制成新型捕收剂MC。引进MC进行浮选试验及工业试验,通过原矿性质分析,详细掌握金的赋存状态、嵌布特征和粒度特性等,通过实验室浮选试验确定最佳的磨矿细度、MC用量、矿浆pH值和活化剂用量等工艺参数,并与现场捕收剂体系浮选指标进行对比。试验结果表明,使用MC作为捕收剂,金精矿品位由原来的28.09 g/t提高到34.46 g/t,金回收率由84.85%提高到88.31%,回收率提高3.46%,取得良好的技术指标,实现金精矿品位与回收率的同步提升,预计年增加经济效益1300余万元。

异戊基黄药与水杨羟肟酸对硅孔雀石硫化浮选行为的影响

为提高硅孔雀石浮选回收率,通过单矿物浮选试验,研究了异戊基黄药与水杨羟肟酸对硅孔雀石硫化浮选行为的影响,通过接触角测试、Zeta电位测试、红外光谱分析等手段对药剂与硅孔雀石表面的作用机理进行了分析。结果表明,组合捕收剂的作用效果好于单一捕收剂,可以将硅孔雀石的浮选回收率提高了18.82个百分点;组合捕收剂会使矿物表面接触角增大,负电性增强,使得药剂在矿物表面产生更强的化学吸附,从而提高了硅孔雀石的浮选回收率。

超声波预处理氧化钙对改善黄铜矿浮选效果的机理分析

为揭示超声波预处理氧化钙对改善黄铜矿浮选效果的机理,以超声预处理的氧化钙为调整剂进行了黄铜矿的浮选试验。采用FTIR等手段对超声预处理的氧化钙溶液进行了表征。结果表明,适宜超声功率处理的氧化钙溶液对黄铜矿浮选效率的影响较为明显。500 g/t的氧化钙经输出功率为216 W的超声波处理后,精矿中铜的回收率达到了83.23%,与未处理相比提高了9.48百分点。适宜的超声波处理氧化钙溶液可使Ca^(2+)、Ca(OH)+和OH-等离子的含量增多,其中的Ca^(2+)、Ca(OH)+等离子可减弱矿泥对浮选药剂的消耗。此外,适宜的超声功率预处理还可使氧化钙溶液中有利于黄铜矿浮选的游离水羟基含量提高3.13百分点,进而改善黄铜矿的浮选效果。研究对超声波技术在浮选领域的应用具有一定的借鉴意义。