电解还原法强化高硫煤浮选脱硫机理研究

采用电解还原法对高硫煤预处理后，使煤表面的含氧官能团减少，疏水性增强；同时，黄铁矿表面初始氧化产物如单质硫和多硫化物被还原，亲水性增强．煤粒和黄铁矿颗粒两者的表面性质向相反的方向改性，从而实现强化浮选分离的目的，理论上分析了煤和黄铁矿表面的改性机理，并通过试验验证了电解还原法强化浮选能够明显地降低浮选精煤中的硫分．对不同煤样的浮选结果表明：北宿煤样的黄铁矿脱除率可达89％以上。     

新型煤炭脱硫降灰浮选药剂BET的试验研究

以BET为新型煤炭浮选药剂,用单矿物实验方法,分别对煤,煤系黄铁矿和煤矸石进行脱硫降灰的试验研究,并以煤炭常用浮选药剂GF,FS202作试验对比,结果表明：尽管BET的用量分别是GF,FS202用量的1／10和1／100,但对黄铁矿,煤矸石等捕收性和选择性明显优于GF,FS202,且不受pH条件的影响,与其它3种同系物（AET,DET,HET）在脱硫降灰方面综合比较表明,BET的效果最好,具有用量少,选择性强等优点,是一种应用前景良好的煤炭浮选药剂。     

低碱度下组合抑制剂对铅铁硫化矿的抑制性能及作用机理

纯矿物试验表明，在碱性条件下DS YD对黄铁矿有抑制作用，而对方铅矿则没有抑制作用；人工混合矿物和实际矿石试验结果证实，用石灰调浆到pH=9，组合抑制剂DS YD能有效实现方铅矿和黄铁矿的浮选分离，精矿含Pb57．89％，铅回收率达到84．78％，并且不影响锌的浮选效果．矿物表面黄药吸附量测定结果表明，组合抑制剂对不同矿物表面竞争吸附能力的差异是低碱度矿浆条件下实现有效分选的主要原因．     

白钨矿捕收剂的温度响应机制研究

为探究不同白钨矿捕收剂对环境温度的响应差异和机制.采用单矿物浮选试验,系统研究了油酸钠和3种羟肟酸浮选白钨矿的温度响应规律,并通过接触角试验、表面张力测量、流变学研究、浊度试验、Zeta电位测试以及吸附量试验,揭示了温度对捕收剂性能影响的内在机制.结果表明：随着浮选温度的降低,所有捕收剂的捕收能力均有所减弱,其中油酸钠受温度影响更为显著.温度降低导致捕收剂表面张力增加、矿浆黏度增大、药剂溶解性变差.这些因素共同作用,使得捕收剂分子与矿粒的碰撞概率下降,药剂在矿粒表面的吸附量减少,最终导致作用于白钨矿颗粒表面的药剂分子数量减少,降低了矿粒表面的疏水性,严重恶化了浮选效果.     

利用磷灰石实现硫化矿浮选废水回用的试验评价

出于环境的考虑，越来越多的选矿厂均利用回水以减轻废水对环境的冲击和对水资源的依赖．工业生产经验表明，回水使用量的增加会对浮选带来不利的影响，尤其是对复杂矿化矿的优先浮选．浮选选择性降低的主要原因是溶液中重金属离子对闪锌矿或黄铁矿的意外活化．本文应用微型浮选试验，吸附试验和表面测试研究了利用磷灰石来实现硫化矿浮选废水回用的可行性．试验表明，磷灰石可增强对闪锌矿的抑制而提高浮选的选择性．微型浮选和表面测试表明，磷灰石与闪锌矿竞争吸附溶液中的重金属，从而降低闪锌矿表面的重金属浓度．     

磁化浮选工艺脱硫降灰的研究

针对细粒煤脱硫难的问题,采用磁化浮选工艺对高硫煤进行脱硫降灰的研究,利用煤与黄铁矿的磁性及可浮性的差异进行分离。实验证明,该方法具有一定的优越性,与常规浮选法相比脱硫率提高７％。     

红假单胞菌在煤系黄铁矿表面吸附量的测定

微生物在黄铁矿表面吸附量的大小，直接影响微生物对黄铁矿的表面改性，决定浮选脱硫效果的优劣．利用红假单胞菌，通过测定吸附前后菌液浓度的变化，对煤系黄铁矿进行吸附量测定试验，重点考察了菌种的浓度、矿浆浓度、pH值等因素对吸附量的影响．研究结果表明，红假单胞菌在黄铁矿表面的吸附量遵守Langmuir等温方程式，吸附量与矿浆浓度成反比，pH值对红假单胞菌吸附量有影响，在中性环境下吸附量最高，在碱性环境下吸附量较小，在酸性环境下吸附量最低．红假单胞菌与黄铁矿的吸附作用中，存在静电引力．     

脂类捕收剂DLZ对黄铜矿和黄铁矿浮选的选择性作用

通过浮选实验、吸附量和红外光谱测定,考察了捕收剂DLZ对黄铜矿和黄铁矿浮选性能的影响及作用机理.结果表明:DLZ在pH=2.7～12.05时对黄铜矿的捕收能力强,最大回收率95.7%,而对黄铁矿的捕收能力弱,且PH=6.9～12.05时其回收率小于10%.用CaO作pH调整剂时,在pH=7～11时黄铜矿的回收率与用NaOH调PH相差不大,但黄铁矿可浮性被抑制,回收率低于5%.DLZ在黄铜矿上的吸附量比在黄铁矿上的大,特别是强碱条件下;其吸附量随用量的增加而增大.DLZ与矿物作用的红外光谱分析表明:黄铜矿与DLZ作用后出现了DLZ的相关特征吸收峰,而黄铁矿与DLZ以及Cu~(2+)作用前后的红外光谱曲线基本没有变化,可见DLZ在黄铜矿表面的吸附属于化学吸附,在黄铁矿表面的吸附属于物理吸附.     

捕收剂CSU-A与黄铜矿作用机理

通过矿物浮选实验、吸附量测试以及红外光谱分析，研究CSU—A与黄铜矿和黄铁矿相互作用的规律．浮选实验结果表明，当CSU—A的质量浓度为6mg／L，溶液pH值为9．0～9．5时，CSU—A对黄铜矿捕收能力强，对黄铁矿捕收能力弱；红外光谱分析结果表明，捕收剂CSU—A与黄铜矿和黄铁矿作用前、后的红外光谱图明显不同，在黄铜矿与药剂作用后出现了6cm^-1的波数位移，而黄铁矿与捕收剂作用前、后的红外光谱图基本上没有变化．由此可以确定，捕收剂CSU—A在黄铜矿表面发生了化学吸附，而在黄铁矿表面仅是简单的物理吸附．捕收剂CSU—A具有选择性的主要原因是在黄铜矿和黄铁矿表面发生吸附的形式不同．     

超声波处理对煤泥特性的影响研究

为了提高煤泥浮选的效率和选择性，提出了在浮选前对煤泥进行超声波预处理的方法．利用扫描电镜、激光粒度仪和图像识别软件等研究了超声处理对煤泥特性的影响．比较了超声波处理前后相同粒级煤泥的产率、硫分、灰分和圆形系数，分析了超声波处理前后煤泥颗粒的表面状态，并用真空浮选试验进行了验证．浮选速度试验结果表明，超声处理后精煤的硫分、灰分较超声波处理前分别降低了33．84％和32．09％，前2min的精煤产率平均提高了约10％．试验证明超声处理改变了煤泥颗粒的大小、形状以及煤粒表面的状态，促使煤粒与黄铁矿、矸石解离，因此超声波预处理是煤泥浮选脱硫降灰的一种有效方法．     

Research on Effect of Magnetized Pulp on Coal Slime Flotation

Effect of magnetization on oxygen concentration, pH, surface zeta potential, and wet heat of flotation pulp were researched. The result shows that magnetization treatment can improve the floatablility of coal and increase the difference in wet heat among coal, refuse, and pyrite, which is favorable for slime flotation and for removing sulfur and ash from coal.     

Study of Enhanced Fine Coal De-sulphurization and De-ashing by Ultrasonic Flotation

The feasibility of using ultrasound to enhance the performance of de-sulphurization and de-ashing during slime flotation was investigated. The Setararn C80 calorimeter, the contact angle gauge DCAT21 and an electrophoresis apparatus were used to study the surface nature of coal, pyrite and refuse before and after ultrasonic conditioning. The yield, ash and sulfur contents of equally sized coal slimes were also measured before and after ultrasonic conditioning. The results show that ultrasonic conditioning can drive the separation of pyrite and refuse from coal. After ultrasonic conditioning the hydrophobicity of coal and hydrophilicity of pyrite and refuse increase. The perfect index of flotation, the perfect index of de-sulphurization and the percentage of de-sulphurization increase by 22.51%, 25.36% and 2.49%, respectively. This study shows that ultrasonic conditioning can enhance the performance of de-sulphurization and de-ashing of coal flotation methods.     

Effect of pyrite content of feed and configuration of locked particles on rougher flotation of copper in low and high pyritic ore types

Misreported pyrite into copper concentrates dramatically declines copper grade and recovery. Copper flotation can be also more complicated if flotation feed comes from an elevated-pyritic copper ore. In this investigation, the effect of two different ore types(high pyritic and low pyritic feeds) was studied on rougher stage of industrial copper flotation circuit. Samples were taken from different streams and the structure of chalcopyrite within the pyrite and non-sulfide gangue minerals was examined in various size fractions for mentioned ore types. Results indicated that 72% and 56% of the total floated pyrite was transferred to concentrate in first four cells in the low and high pyritic feeds, respectively. Whereas, this proportion for floated SiO_2 in last ten cells was detected as 72% and 71%, respectively. A detailed interpretation of the effect of locked particles in different size fractions on rougher flotation cells is studied from industrial point of view.     

Effect of organic depressant lignosulfonate calcium on separation of chalcopyrite from pyrite

In order to selectively separate chalcopyrite from pyrite, the effect of organic depressant lignosulfonate calcium (LSC) on the flotation separation of chalcopyrite from pyrite was investigated by flotation tests. The depression mechanism was studied by Fourier-transform-infrared (FTIR) analysis. The flotation tests of single mineral show that LSC can depress the flotation of pyrite in a certain pH range, but it has little effect on chalcopyrite flotation. Flotation separation of a mixture of chalcopyrite and pyrite can be completed to obtain a copper concentrate grade up to 24.73% with a recovery of 80.36%. IR analysis shows that LSC and butyl xanthate compete in absorption on pyrite surface, and there exists an LSC characteristic peak on pyrite surface. There is little adsorption of LSC on chalcopyrite.     

利用自燃模拟试验装置分析影响矸石自燃的因素

通过大试样量自燃倾向性实验(模拟试验)装置,对煤矸石中硫铁矿、含水量、孔隙率对煤矸石氧化升温的影响进行的实验研究,得到了其对矸石氧化升温的影响规律,为了解矸石自燃规律和寻找控制措施提供依据。     

Fast recognition using convolutional neural network for the coal particle density range based on images captured under multiple light sources

A method based on multiple images captured under different light sources at different incident angles was developed to recognize the coal density range in this study. The innovation is that two new images were constructed based on images captured under four single light sources. Reconstruction image 1 was constructed by fusing greyscale versions of the original images into one image, and Reconstruction image 2 was constructed based on the differences between the images captured under the different light sources. Subsequently, the four original images and two reconstructed images were input into the convolutional neural network AlexNet to recognize the density range in three cases: −1.5 (clean coal) and + 1.5 g/cm³ (non-clean coal); −1.8 (non-gangue) and + 1.8 g/cm³ (gangue); −1.5 (clean coal), 1.5–1.8 (middlings), and + 1.8 g/cm³ (gangue). The results show the following: (1) The reconstructed images, especially Reconstruction image 2, can effectively improve the recognition accuracy for the coal density range compared with images captured under single light source. (2) The recognition accuracies for gangue and non-gangue, clean coal and non-clean coal, and clean coal, middlings, and gangue reached 88.44%, 86.72% and 77.08%, respectively. (3) The recognition accuracy increases as the density moves further away from the boundary density.