A comparison of anionic and cationic flotation of a siliceous phosphate rock in a column flotation cell

Flotation performance of a de-slimed (-150 + 53 μm)Jordanian siliceous phosphate was evaluated in a batch laboratory flotation column 100 cm high and 5 cm inside diameter. The collector used during anionic flotation was sodium oleate while an amine acetate (AEROMINE 3100C) was used for cationic flotation. Flotation comparison at different collector dosage, superficial gas velocity, and frother concentration showed that the maximum difference in performance between cationic and anionic flotation was obtained with these flotation parameters: 30 × 10 6 (mg/L) frother concentration, 250 g/tcollector concentration, and 3.4 cm/s superficial gas velocity. At these operating conditions amine (cationic) flotation gave 7% higher flotation recovery, a 6% cleaner concentrate grade, and was 6% more efficient at removing silica.     

Nanobubble generation and its applications in froth flotation(part Ⅳ): mechanical cells and specially designed column flotation of coal

Coal is the world's most abundant fossil fuel.Coal froth flotation is a widely used cleaning process to separate coal from mineral impurities.Flotation of coarse coal particles,ultrafine coal particles and oxidized coal particles is well known to be difficult and complex.In this paper,the nanobubbles' effects on the flotation of the varying particle size,particle density and floatability coal samples were evaluated using a bank of pilot scale flotation cells,a laboratory scale and a pilot scale specially designed flotation column.The parameters evaluated during this study include the flow rate ratio between the nanobubble generator and the conventional size bubble generator,the superficial air velocity,collector dosage,frother concentration,flotation feed rate,feed solids concentration,feed particle size,and the superficial wash water flow rate,etc.The results show that the use of nanobubbles in a bank of mechanical cells flotation and column flotation increased the flotation recovery by 8%～27% at a given product grade.Nanobubbles increased the flotation rate constants of 600～355,355～180,180～75,and 75～0 microns size coal particles by 98.0%,98.4%,50.0% and 41.6%,respectively.The separation selectivity index was increased by up to 34%,depending on the flotation feed characteristics and the flotation conditions.     

纳米泡提高细粒煤浮选效果的研究

泡沫浮选槽中微细粒级低效浮选的原因是颗粒与气泡的碰撞概率低,而粗颗粒浮选回收差的原因是大量颗粒从气泡上脱落,采用文丘里管产生纳米泡,研究了利用纳米泡提高细粒煤浮选效果的机理,结果表明:纳米泡浮选过程中,纳米泡会优先聚集在疏水性颗粒表面,通过调整给料速度、捕收剂添加量等浮选条件,可燃体回收率提高10%～30%,纳米泡起到了辅助捕收的作用,并可以减少药剂用量1/3～1/2.     

Distribution behavior of collector in the desilication system of bauxite flotation

Ｓｔｕｄｙｉｎｇｔｈｅｄｉｓｔｒｉｂｕｔｉｏｎｌａｗｏｆｃｏｌｌｅｃｔｏｒｓｉｎｔｈｅｆｌｏｔａｔｉｏｎｓｙｓｔｅｍｉｓｈｅｌｐｆｕｌｔｏｕｓｉｎｇｆｌｏｔａｔｉｏｎａ ｇｅｎｔｓｒｅａｓｏｎａｂｌｙ ,ｓａｖｉｎｇｔｈｅｃｏｓｔｏｆｆｌｏｔａｔｉｏｎｐｒｏ ｃｅｓｓａｎｄｄｅｃｒｅａｓｉｎｇｔｈｅｐｏｌｌｕｔｉｏｎｏｆｐｏｉｓｏｎｏｕｓａ ｇｅｎｔｓ.Ｔｈｅｒｅｗｅｒｅａｆｅｗｒｅｐｏｒｔｓ[1 3] ａｂｏｕｔｔｈｅｄｉｓ ｔｒｉｂｕｔｉｏｎｂｅｈａｖｉｏｒｏｆｘａｎｔｈａｔｅａｎｄｄｉｔｈｉｏｐｈｏｓ…     

新型捕收剂常温反浮选铁矿石的试验

以司家营铁矿磁选精矿为研究对象,采用新型改性脂肪酸类捕收剂,在浮选温度为25℃下,通过条件试验确定最佳药剂用量(粗选氢氧化钠1 500 g/t,淀粉650 g/t,石灰550 g/t,捕收剂450 g/t;精选石灰200 g/t,捕收剂450 g/t),进行一粗一精开路浮选得到精矿品位66.56%,回收率为70.64%,并经过闭路流程获得精矿品位65.79%,回收率为83.01%,尾矿品位13.58%的选矿指标.试验表明,该新型捕收剂选择性强,常温下水溶性好,解决了常规加温浮选能耗大、成本高的问题.     

胶磷矿柱式双反浮选工艺研究

针对我国西南地区难选硅-钙质胶磷矿,采用旋流-静态微泡浮选柱对其进行了柱式双反浮选工艺的研究.以硫酸和磷酸作为磷矿物抑制剂,脂肪酸类药剂PA-64作为碳酸盐矿物捕收剂,胺类药剂GE-601作为硅酸盐矿物捕收剂,考察了磨矿细度、药剂用量、循环泵工作压力等因素对浮选指标的影响.研究结果表明,采用旋流-静态微泡浮选柱双反浮选工艺,可以得到精矿P_2O_5品位30.49%,MgO含量0.73%,磷回收率81.03%的浮选指标,简化了胶磷矿浮选工艺流程.     

不同表面活性剂对改性脂肪酸捕收剂的增效作用

为了考查几种表面活性剂对磷矿捕收剂的增效作用,以贵州瓮福白岩磷矿为试验样品,通过浮选试验研究了表面活性剂吐温-80、吐温-80和十二烷基硫酸钠1∶1混合物、烷基酚聚氧乙烯醚、脂肪酸甲酯α-磺酸钠盐-2、脂肪酸甲酯α-磺酸钠盐-3对改性脂肪酸类捕收剂H-2增效作用.结果表明,对于贵州瓮福白岩磷矿,通过在捕收剂中添加表面活性剂,可以提高捕收剂对磷酸盐矿物的选择性.添加表面活性剂烷基酚聚氧乙烯醚为捕收剂H-2的13%时,选矿回收率从75.02%提高到93.14%,选矿效率从2.15%提高到7.87%.表面活性剂中烷基酚聚氧乙烯醚的增效作用优于吐温-80、吐温-80和十二烷基硫酸钠1∶1混合物、脂肪酸甲酯α-磺酸钠盐-2、脂肪酸甲酯α-磺酸钠盐-3,以表面活性剂烷基酚聚氧乙烯醚复配H-2所得到的新型药剂,浮选性能要优于分析纯的油酸钠和工业应用的捕收剂FMS-01.     

辽宁凤城含铀硼铁复合矿分选研究

针对辽宁凤城硼铁复合矿资源,在综合测定矿石成分及其目的矿物嵌布特性的基础上开展矿物分选试验研究,采用弱磁场磁选机回收磁铁矿,应用水力旋流器、螺旋溜槽以及摇床等重选设备回收晶质铀矿物,以氧化石蜡皂作为捕收剂、Na2CO3作为矿浆pH值调整剂浮选分离硼矿物．结果表明,当磨矿细度小于0．047mm占99．26％时,铁精矿中TFe品位达到60．27％,回收率为79．21％;重选回收铀矿物效果较好,但是浮选分离指标有待大幅度提高．进一步提高目的矿物单体解离度是改善分选指标的关键．     

Effectiveness of sodium silicate as gangue depressants in iron ore slimes flotation

The recovery of iron from the screw classifier overflow slimes by direct flotation was studied.The relative effectiveness of sodium silicates with different silica-to-soda mole ratios as depressants for silica and silicate bearing minerals was investigated.Silica-to-soda mole ratio and silicate dosage were found to have significant effect on the separation efficiency.The results show that an increase of Fe content in the concentrate is observed with concomitant reduction in SiO2 and Al2O3 levels when a particular type of sodium silicate at a proper dosage is used.The concentrate of 58.89wt％ Fe,4.68wt％ SiO2,and 5.28wt％ Al2O3 with the weight recovery of 38.74％ and the metal recovery of 41.13％ can be obtained from the iron ore slimes with 54.44wt％ Fe,6.72wt％ SiO2,and 6.80wt％ Al2O3,when Na2SiO3 with a silica-to-soda mole ratio of 2.19 is used as a depressant at a feed rate of 0.2 kg/t.     

On the optimization of froth flotation by the use of an artificial neural network

A multi layered, feed forward Artificial Neural Network (ANN) was used to study the effect of feed mean size, collector dosage and impeller speed on flotation recovery and grade. The results of 30 flotation experiments conducted on Jordanian siliceous phosphate were used for training the network while another 10 experiments were used for validation. Simulation results showed that a four layer network with a [9 11 5 9 2] architecture was the one that gave the least mean squared error (MSE). Using this ANN to optimize the flotation process showed that the optimum flotation parameters were 321.28 μm for the feed mean size,0.7354 kg/TOF for the collector dosage and 1225.25 RPM for the impeller speed. Studying the effect of these parameters on flotation recovery and grade was done by analysis of variance, ANOVA. The results showed that grade was more sensitive to changes in flotation parameters than was recovery. They also showed that changes in collector dosage had a more significant effect on flotation grade and recovery than did changes in feed mean size or impeller speed.     

云南会泽高镁中低品位胶磷矿单一反浮选

为了降低云南会泽高镁中低品位磷矿的氧化镁的含量,提高五氧化二磷的品位,采用全硫酸一粗一扫的单一反浮选工艺对云南会泽高镁中低品位磷矿进行了试验.在原矿五氧化二磷的品位为23.71％,最佳磨矿细度为-0.074 mm 88.2％的条件下,以硫酸作为pH调整剂和抑制剂（不需要添加磷酸等其他的抑制剂）,以改性的棉籽油脂肪酸皂为捕收剂,进行浮选试验.结果表明：在粗选硫酸用量为10 kg/t,扫选硫酸用量为6 kg/t,捕收剂TSM-2用量分段加药,第一段粗选添加1.2 kg/t,第二段为0.3 kg/t时,获得精矿五氧化二磷品位为30.09％,回收率达到86.53％,氧化锰由原矿的4.55％降至精矿的0.78％,脱镁率为88.13％的较好指标.为云南会泽磷矿的利用开辟了新途径.     

烷基丙二胺与醚胺组合反浮选石英性能研究

通过N-烷基1,3丙二胺与醚胺组合,得到成本相对较低,浮选泡沫量少的药剂组合。单矿物可浮性试验表明:E1、M1、M3有很好的选择性但药剂用量较大,E2、M2有很好的捕收性,选择性稍差,E3具有较好的选择性和捕收性。通过组合药剂研究,寻找到了组合药剂GE-651C(M1∶E3=7∶3),降低了药剂成本而性能不受影响。实际铁精矿开路浮选表明:GE-651C用量为180 g/t,精矿品位为60.27%,回收率为66.78%。消泡试验表明,GE-651C的泡沫少,性脆易消,有利于泡沫产品的后续处理。     

气固循环流化床碳化室局部CO_2摩尔分数的研究

在内径0.1 m,高1.0 m的碳化室(浓相区)和高3.0 m上升段的气固循环流化床反应器内,分别以混合气(空气85%(体积分数)和CO215%(体积分数))和CaO颗粒(平均粒径0.85 mm)为气相和固相,采用不同温度、表观气速和CaO颗粒循环速度,对碳化室不同高度及出口局部CO2摩尔分数进行了系统研究。应用计算流体力学(CFD)软件Fluent 6.2对碳化室不同高度及出口局部CO2摩尔分数进行了模拟计算。在模拟计算过程中,通过自编C语言程序,将CaO与CO2反应的动力学模型与Fluent 6.2中的传统模型结合。模拟结果显示:最佳反应温度为925K;表观气速为0.10 m.s-1;CaO的循环速度为0.12 m.s-1。在较低温度下,碳化室内不同高度局部CO2摩尔分数的模拟结果与实验数据吻合良好。随温度增加,计算值与实验值误差增大。     

中低品位胶磷矿新型捕收剂的浮选性能

以碘值135的棉油脂肪酸作为原料通过合成与复配方法获得一种新型磷矿选矿捕收剂;首先将脂肪酸与酰胺药剂进行酰胺化,然后在合成的药剂中复配一定量的烷基酚聚氧乙烯醚表面活性剂.通过气相色谱分析了该脂肪酸的组成,以贵州磷矿为对象,利用常温浮选试验研究了该捕收剂的选矿特性.试验结果表明,碘值135脂肪酸中油酸、亚油酸含量较高,在碳链结构中双键、三键数目多.经过酰胺化和复配15%的表面活性剂烷基酚聚氧乙烯醚,提高了脂肪酸对磷酸盐矿物的浮选效果,在常温浮选过程中,降低了捕收剂的用量.在磨矿细度为-0.074 mm 79.83%,采用常温正反浮选工艺,获得了五氧化二磷为30.12%精矿,产率为71.20%,回收率为92.90%的选矿指标.     

Parametric study of electrostatic separation of South African fine coal

The fact that water requirements are a major problem for present and future developments in material beneficiation, and the construction of a new power plant in South Africa, forms the basis for the utilization of a Rotary Triboelectrostatic Separator (RTS) for beneficiation of South African pulverized coal. The cleaning potential of Majuba and Koorfontein coal was first evaluated using kinetic froth flotation tests on the -177μm coal fraction. The RTS tests were conducted under varied process parameters. Parameters such as applied separating voltage, air injection velocity, particle feed rate and splitter position were investigated. Two stage separation results show that the RTS reduced Majuba coal initially containing about 30% ash to a clean product of 14.30%, or 19.46%, ash at a combustible recovery of 15.10%, or 53.02%, respectively. Similar separation performance was also achieved with the Koorfontein coal. The mineral and organic compositions in the feed, after single stage and after the second stage separations were characterized using X-ray diffraction analysis. The results show a better separation for the second stage coal products.     

巴西磷矿泥浆中磷灰石的回收

针对我国严重匮乏可溶性钾盐资源,而非可溶性钾资源却非常丰富,如磷钾伴生矿,因而探索从磷钾伴生矿中提取可溶性钾具有重要意义. 本文强化了磷钾伴生矿的酸浸过程,研究了在HCl-CaF₂体系下,表面活性剂对磷钾伴生矿中钾浸出的影响. 结果表明:阴离子表面活性剂可以强化钾的浸出,阳离子表面活性剂对钾的浸出未产生明显影响,非离子表面活性剂会抑制钾的浸出. 通过筛选得到较佳的表面活性剂为十二烷基硫酸钠（SDS）,其添加量为1.25 g/L,与未添加SDS的相比,钾浸出率提高了约8.5%,达到了98.01%     

Prediction of operational parameters effect on coal flotation using artificial neural network

Artificial neural network procedures were used to predict the combustible value (i.e. 100-Ash) and combustible recovery of coal flotation concentrate in different operational conditions. The pulp density, pH, rotation rate, coal particle size, dosage of collector, frother and conditioner were used as inputs to the network. Feed-forward artificial neural networks with 5-30-2-1 and 7-10-3-1 arrangements were capable to estimate the combustible value and combustible recovery of coal flotation concentrate respectively as the outputs. Quite satisfactory correlations of 1 and 0.91 in training and testing stages for combustible value and of 1 and 0.95 in training and testing stages for combustible recovery prediction were achieved. The proposed neural network models can be used to determine the most advantageous operational conditions for the expected concentrate assay and recovery in the coal flotation process.     

铝硅酸盐矿物新型浮选捕收剂的研究

考察了自行合成的新型阳离子表面活性剂QAS222对高岭石、叶蜡石和伊利石等铝硅酸盐矿物的浮选行为,试验研究结果表明：广泛矿浆pH范围内,新型阳离子表面活性剂QAS222对铝硅酸盐矿物既表现出较强的捕收力,又显示良好的选择性,是铝硅酸盐矿物的有效捕收剂,可应用于铝硅酸盐矿物的浮选富集,同样也可用于铝土矿、铁矿、萤石矿等选别过程的反浮选脱硅;在矿浆pH=11时,以QAS222为捕收剂,不添加其它任何抑制剂,成功地实现不同铝硅比的人工混合矿的反浮选脱硅,并获得较好的选别指标——当给矿A/S仅有2．7时,仍能获得精矿A／S为12．82,其中Al2O3品位77．79％、回收率69．91％的较好指标,且当给矿A／S不断增大时,精矿中的A/S,Al2O3的品位和回收率都有所提高．     

Effect of agitation on the characteristics of air dense medium fluidization

In order to study the effect of agitation on the characteristics of air dense medium fluidization, we designed and constructed an agitation device. Analyses were then conducted on the fluidization characteristics curves, the bed density stability and the average bubble rise velocity Uaunder different agitation conditions. The results indicated that a lower bed pressure drop(without considering lower gas velocity in a fixed bed stage) and higher minimum fluidized velocity are achieved with increasing agitation speed.The height d(distance between the lower blades and air distribution plate) at which the agitation paddle was located had a considerable effect on the stability of the bed density at 9.36 cm/s U 10.70 cm/s. The higher the value of d, the better the stability, and the standard deviation of the bed density fluctuation r dropped to 0.0364 g/cm~3 at the ideal condition of d = 40 mm. The agitation speed also had a significant influence on the fluidization performance, and r was only 0.0286 g/cm~3 at an agitation speed of N = 75 r/min. The average bubble rise velocity decreased significantly with increasing agitation speed under the operating condition of 1.50 cm/s U–U_(mf) 3.50 cm/s. This shows that appropriate agitation contributes to a significant improvement in the fluidization quality in a fluidized bed, and enhances the separation performance of a fluidized bed.     

高效反浮选捕收剂的合成与应用

针对传统脂肪酸捕收剂选择性差、常温下分散性和溶解性差的问题,以工业棉籽油酸为原料,经高温高压使脂肪酸的双键水解而引入羟基活性基团,进一步与助剂按比例复配得到一种高效反浮选捕收剂HY.将其用于宜昌某高镁磷矿的浮选试验,经一反一扫简单浮选工艺流程获得了精矿五氧化二磷品位34.59%,五氧化二磷回收率96.46%,氧化镁品位0.28%的良好浮选选指标,氧化镁脱除率高达95%,各指标优于公开招标各项指标要求,且浮选在常温下进行,药剂用量仅0.84kg/t.表明反选捕收剂HY具有良好的浮选性能,其化学修饰改性改善了捕收剂的常温溶解性同时增强了其对钙离子、镁离子的选择性.