Kinetics of the reactions in the smelting furnace of the Mitsubishi process

In this paper, the authors present the results of theoretical calculations on the rates at which copper concentrate particles and silica particles dissolve in the matte in the smelting furnace of Mitsubishiprocess. Those calculations indicate that the concentrate particles dissolve rapidly in matte, in less than 1 ms, whereas silica particles dissolve at a much slower rate, and they dissolve mainly in the bulk matte in the smelting furnace. Some advantages of bath smelting over flash smelting are given. For more information, contact Zenjiro Asaki, Mitsubishi Materials Corporation, Central Research Institute, 1-297 Kitabukuro-cho, Omiya, Saimtama, 330-8508, Japan.     

颗粒增强铸造铝基复合材料的研究

本文探讨了用搅拌铸造法,采用常规的熔炼加工设备和工艺,制造ＳｉＣ颗粒增强铝基复合材料的可行性;研究了不同ＳｉＣ含量的复合材料的显微组织;试验表明：复合材料中ＳｉＣ颗粒分布较为均匀,其力学性能均优越于基体合金,弥散分布的ＳｉＣ颗粒是复合材料力学性能优异的主要原因。     

The electromechanical principle of electrorheological fluid-assisted polishing

An up-to-date abrasive polishing process using electrorheological (ER) fluid, known as ER fluid assisted polishing, is potentially useful in the surface finish of three dimensional micro or meso-scale devices. For a more detailed understanding of this process, the electrostatic principle of how an ER fluid functions on the polishing is described. Dielectric particles suspended in a dielectric fluid are polarized with the application of an electric field, and they experience the dipolar interaction force each other and the translational force along the field, defined as dielectrophoresis due to the non-uniform electric field. As a result of the calculations of the exerted forces on the ER and abrasive particle suspended in silicone oil, ER particles strongly attract the abrasive particles as well as each other when they are aligned with the electric field. Because this attraction force is much higher than the dielectrophoretic force, abrasive particles adhere to ER particles which concentrate on a tool along the field lines. The behavior of particles is observed by the CCD camera, and borosilicate glass is polished to evaluate machining performance.     

生物浸出体系中中等嗜热菌对锌冶炼窑渣中金属的提取及其电化学特性的影响(英文)

研究中等嗜热菌对锌冶炼窑渣中金属提取的影响以及生物浸出过程中锌冶炼窑渣碳糊电极的电化学特性。结果表明,在矿浆浓度2%、pH1.0、温度65°C、转速为120r/min的浸出条件下,去除生物浸出体系中吸附菌后,废渣中Fe、Cu和Zn的浸出率分别为86.7%、90.3%和66.7%,而在没有去除吸附菌体系中3种金属的浸出率分别为91.9%、96.0%和84.5%。对生物浸出渣和酸浸渣表面细菌分泌物进行FT-IR测试分析可知,生物浸出渣颗粒表面出现了新的官能团振动峰,如1007cm1和1193cm1处的峰,间接说明残渣颗粒表面吸附细菌的存在。生物浸出体系和空白体系的循环伏安曲线和塔菲尔曲线特性进一步表明生物浸出体系中细菌促进了锌冶炼窑渣中有价金属的溶出。     

Mathematical modelling and numerical optimization of particle heating process in copper flash furnace

A mathematical model of the particle heating process in the reaction shaft of flash smelting furnace was established and the calculation was performed. The results indicate that radiation plays a significant role in the heat transfer process within the first 0.6 m in the upper part of the reaction shaft, whilst the convection is dominant in the area below 0.6 m for the particle heating. In order to accelerate the particle ignition, it is necessary to enhance the convection, thus to speed up the particle heating. A high-speed preheated oxygen jet technology was then suggested to replace the nature gas combustion in the flash furnace, aiming to create a lateral disturbance in the gaseous phase around the particles, so as to achieve a slip velocity between the two phases and a high convective heat transfer coefficient. Numerical simulation was carried out for the cases with the high-speed oxygen jet and the normal nature gas burners. The results show that with the high-speed jet technology, particles are heated up more rapidly and ignited much earlier, especially within the area of the radial range of R=0.3–0.6 m. As a result, a more efficient smelting process can be achieved under the same operational condition.     

Lubricated Sliding Wear Behavior of a Cast Iron: Effect of Graphite and/or Talc Fraction in Oil

The effects of suspended solid lubricant (graphite and/or talc) particles in oil on the sliding wear response of a cast iron have been studied in this investigation. The role played by the changing concentration of the talc and graphite particles added to the oil separately as well as in combination toward controlling the wear behavior of the cast iron has also been analyzed. The investigation strongly suggests beneficial effects of the solid lubricant particles suspended in lubricating oil in terms of decreasing wear rate, frictional heating, and friction coefficient. Interestingly, increasing concentration of the suspended lubricant particles in oil led to reduction in the mentioned properties initially followed by the attainment of the minimum at a specific concentration of the solid lubricants. At still higher concentrations, the trend reversed in the case of wear rate and friction coefficient while it remained unaffected as far as the influence on frictional heating is concerned. Formation of stable lubricating film/layer was noted to be responsible for the improved wear performance of the samples while rupture of the lubricant film led to deterioration in wear behavior.     

某电厂汽轮机20Cr1Mo1VNbTiB钢汽门螺栓开裂失效分析

针对某电厂汽轮机用20Cr1Mo1VNbTiB钢高压调速汽门螺栓和中压联合汽门螺栓开裂原因进行了失效分析。分析结果表明:两螺栓样品的化学成分及硬度均符合相关标准要求。两螺栓样品的显微组织局部存在混晶现象,且组织中存在大量大块硬脆的第二相—MC相。组织中大块的硬脆MC相可以作为裂纹形核点,会增加裂纹萌生几率,加速材料裂纹扩展,增加材料开裂失效倾向。该析出相具有较高硬度和高稳定性,热处理难以将其消除,通常在冶炼过程中形成,应加强冶炼工艺管控,避免出现大量大块硬脆的MC相。     

Numerical simulation analysis of Guixi copper flash smelting furnace

A numerical simulation analysis for reactions of chalcopyrite and pyrite particles coupled with momentum,heat and mass transfer between the particle and gas in a flash smelting furnace is presented.In the simulation.the equations governing the gas flow are solved numerically by Eular method.The particle phase is introduced into the gas flow by the particle-source-in-cell technique(PSIC),Predictions including the fluid flow field,temperature field,concentration field of gas phase and the tracks of particles have been obtained by the numerical simulation.The visualized results show that the reaction of sulfide particles is almost completed in the upper zone of the shaft within 1.5m far from the central jet distributor (CJD)type concentrate burner,The simulation results are in good agreement with data obtained from a series of experiments and tests in the plant and the error is less than 2%.     

Formation of arsenic−copper-containing particles and their sulfation decomposition mechanism in copper smelting flue gas

The heat recovery steam generator (HRSG) of copper smelting generates a large number of arsenic−copper- containing particles, and the in-situ separation of arsenic and copper is of importance for cutting off environmental risk and realizing resource recovery. The formation of arsenic−copper-containing particles was simulated, the method of in-situ decomposition of arsenic−copper-containing particles by pyrite was proposed, and the decomposition mechanism was confirmed. It was found that particles with high arsenic content were formed in the simulated HRSG, and copper arsenate was liable for the high arsenic content. Pyrite promoted the sulfation of copper, leading to the in-situ decomposition of copper arsenate. In this process, gaseous arsenic was released, and thus the separation of arsenic and copper was realized.     

Effect of suspended solids on the flow-induced corrosion of a modified Al-2.5Mg alloy in arabian gulf water

Suspended solids increase the rate of corrosion and decrease the resistance of a modified Al-2.5Mg alloy to pitting in Arabian Gulf water. It has been shown by electrochemical studies that the pitting potential of the alloy shifts to more negative values in the presence of suspended solids. The rate of mass transfer and the limiting current is significantly increased by suspended particles.     

A Numerical Study of Suspension Injection in Plasma-Spraying Process

Suspension feedstock in plasma spraying opened a new chapter in coating process with enhanced characteristics. The suspension carrying sub-micron up to few micron-sized particles is radially injected into an atmospheric plasma plume. Understanding the trajectory, velocity, and temperature of these small particles upon impacting on the substrate is a key factor to produce repeatable and controllable coatings. A three dimensional two-way coupled Eulerian-Lagrangian scheme is utilized to simulate the flow field of the plasma plume as well as the interactions between the evaporative suspension droplets with the gas phase. To model the breakup of droplets, Kelvin-Helmholtz Rayleigh-Taylor breakup model is used. After the breakup and evaporation of suspension is complete, the solid suspended particles are tracked through the domain to determine the characteristics of the coating particles. The numerical results are validated against experiments using high-speed imaging.     

Ni-Cu-P合金显微组织和硬度的研究

熔制的Ｎｉ－Ｃｕ－Ｐ合金显微组织由Ｎｉ－Ｃｕ,Ｃｕ－Ｎｉ两种固溶体枝晶和弥散其中的Ｎｉ３Ｐ组成。随着磷含量的增加,Ｎｉ－Ｃｕ－Ｐ合金的硬度显著提高。热处理对Ｎｉ－Ｃｕ－Ｐ合金的显微组织和硬度无显著影响。     

BEHAVIOUR OF FLUORINE IN BLAST-FURNACE SMELTING Ⅴ. AN INVESTIGATION OF THE SLAG-FORMING PROCESSES IN A 11M~3 BLASTFURNACE SMELTING PAO-TOU IRON ORE

在本文中,我们报告了11M~3高炉冶炼包头铁矿时炉料样品包括矿石、初渣、终渣的岩相分析及初渣的化学分析结果,并结合温度测定数据,画出了高炉中等温线及各区域的分市情况,以及各区域炉料中的矿物组成。根据以上实验结果,讨论了冶炼包头铁矿时的初渣形成机理,并指出初渣的性质与一般酸性铁矿不同,此点对高炉的顺行有利。     

熔炼工艺对Mg-Al-Ce-Sb合金铸态显微组织和显微硬度的影响

采用光学显微镜、XRD、扫描电镜、能谱分析等手段相结合的方法,研究了不同浇注温度及Ce、Sb加入顺序对Mg-3%Al-1%Ce-1%Sb合金显微组织及显微硬度的影响.结果表明:熔炼工艺对铸态Mg-3%Al-1%Ce-1%Sb合金中的第二相形态有明显影响.采用同时加入Ce、Sb,在较高温度浇注,可显著减少棒状相的数量,得到以球状颗粒为主的第二相,并使Mg-3%Al-1%Ce-1%Sb合金的显微硬度有所降低.球状颗粒主要为含Ce、Sb、Mg和O或含Mg和Al的相;棒状相主要含有Al、Sb和O.     

CAUSE OF FORMATION OF NODULAR COPPER PARTICLES ON ELECTROREFINED COPPER SUBSTRATE

ＣＡＵＳＥＯＦＦＯＲＭＡＴＩＯＮＯＦＮＯＤＵＬＡＲＣＯＰＰＥＲＰＡＲＴＩＣＬＥＳＯＮＥＬＥＣＴＲＯＲＥＦＩＮＥＤＣＯＰＰＥＲＳＵＢＳＴＲＡＴＥ￥Ｌｉｎ，Ｊｉａｎｘｉｎ；Ｌｉ，Ｘｕｅｌｉａｎｇ；Ｃｈｅｎ，Ｈａｎｈｅ；Ｈｅ，Ｊｉａｎｂｏ（ＨｅｆｅｉＰｏｌ...     

纯镍铸锭锻造开裂及轧制脆断工艺研究

介绍了纯镍在盘圆生产过程中产生的锻造开裂和轧制脆断现象,研究了熔炼工艺、加工过程和热工制度对其的影响.通过研究认为,熔炼工艺和质量是影响的关键,提出取消重熔和减少加热次数可有效消除纯镍加工性能差的结论.     

Mathematical model of pyritic smelting process for copper-nickel mineral in oxygen top-blown furnace

1　INTRODUCTIONTheideaofrefiningcopperandnickelwithpyriticsmeltingprocessinoxygentop blownfurnacehascomeintobeingforitsachievementinoxygen converterofsteelmaking processfrom 196 0s.Thefirstpyriticsmeltingfurnacewithoxygentop blownsmeltingnickelhadbeenputintoproductionatNorthNickelCo .ofRussianin 1986 .Nowadays ,thistech nologyhasbeenimportedandemployedinJinchuanNonferrousMetalCo .ofChina .Inthepastdecades ,theutilizationofflashsmeltingfurnaceinnonferrous makinghasgotextensivedevelopmen…     

An investigation of effective area in electrorheological fluid-assisted polishing of tungsten carbide

Electrorheological (ER) fluid-assisted polishing is a novel polishing method for the finishing of micro-aspheric lens, dies and mirror. This paper investigates the effective area in the ER fluid-assisted polishing of tungsten carbide, which is used as the die material for the mass production of micro-aspheric glass lens. The effective area is defined as the area in which the abrasive particles concentrated in the vicinity of the tool tip makes the effective material removal from the workpiece. The electric field strength applied between the tool and the workpiece is analysed. The interacting forces between particles suspended in the electrorheological fluid are calculated. An approach is proposed to predict the effective area and the experiments are conducted to confirm the validity of the proposed method.     

有色金属冶炼自动控制研究现状与展望

有色金属冶炼需要大量消耗能源,且生产过程废料存在环境污染等问题,以节能减排为目标有必要提升其自动控制水平.从控制角度出发,将有色金属冶炼相关研究成果按控制要素即冶炼模型、控制系统进行划分.针对常规建模方法难以全面反映有色冶炼流程特性的问题,提出未来模型应同时包含化学机理、流场分布等因素;为实现有色金属冶炼控制品质的提升...     

Operation optimization of concentrate burner in copper flash smelting furnace

The software that simulates the flow, temperature, concentration and the heat generation field in the Outkumpu flash smelting furnace, was developed by a numerical method of the particle-gas flow together with some chemical reaction models. Many typical operating conditions were chosen for simulation in order to obtain the effect of the distribution air, process air, central oxygen and the oil-burner position etc. The concepts about optimum op-eration, 3C(concentration of high temperature, high oxygen and laden concentrate particles), are concluded from these simulated results, which have been checked primarily by operational experiments.