硫化铅精矿无SO_2排放反射炉一步炼铅半工业试验

以西部矿业公司自产硫化铅精矿和进口高锌硫化铅精矿为原料 ,在 1m2 的小反射炉上进行了硫化铅精矿还原造锍熔炼的半工业试验。结果表明 :烟气中SO2 含量达标 ,固硫率≥ 96 % ,铅直收率≥ 87% ,总回收率≥ 96 % ,粗铅质量高 ,符合电解精炼要求。说明硫化铅精矿无SO2 排放一步炼铅新工艺实现大规模的工业应用是完全可能的。     

硫化铅精矿无SO2排放反射炉一步炼铅半工业试验

以西部矿业公司自产硫化铅精矿和进口高锌硫化铅精矿为原料,在1m^2的小反射炉上进行了硫化铅精矿还原造锍熔炼的半工业试验,结果表明,烟气中SO2含量达标,固硫率≥96％,铅直收率≥87％,总回收率≥96％,粗铅质量高,符合电解精炼要求,说明硫化铅精矿无SO2排放一步炼铅新工艺实现大规模的工业应用是完全可能的。     

再生铜熔炼过程节能与提质关键技术研究

通过对再生铜熔炼系统进行热工测试及其设备运行状况的分析,发现再生铜直接熔炼制造光亮铜杆的生产过程中存在燃气品质低、燃烧器结构不合理、金属回收率低、产品杂质含量偏高的问题。为解决这些问题,开发出一种净化与水封一体化的重力水除尘器以提高燃气品质;采用螺旋式高速配风燃烧器提高燃料燃烧效率及反射炉内温度分布均匀度;在反射炉熔炼过程中采用低温扒渣技术解决铁类杂质污染液态铜的问题;采用氧化还原期温度调控技术,以提高铜回收率及产品品质、缩短熔炼周期。通过以上多项技术措施的应用,降低了再生铜熔炼过程的能耗及铜损耗,提高了光亮铜杆产品的质量,使产品的伸长率及扭转等性能优于行业标准,同时降低了废气对环境的污染。     

喷枪顶吹熔炼技术的应用

喷枪顶吹熔炼技术的进展传统熔炼有鼓风炉熔炼、反射炉熔炼、电炉熔炼等。传统熔炼流程技术成熟、可靠,简易灵活,设备结构简单。但传统熔炼流程的生产效率低;脱硫率低,硫的回收率低,烟气含SO2浓度很低,低浓度二氧化硫烟气处理费用高,环境污染严重,劳动强度大,生产条件差;燃料率高,对燃料要求苛刻,如鼓风炉熔炼要求用价格较贵的焦炭,电炉熔炼要求有充足的电力。由于传统熔炼流程存在上述问题,因此世界各国都在淘汰传统的鼓风炉熔炼、反射炉熔炼和电炉熔炼等流程,而采用先进的闪速熔炼、熔池熔炼取而代之。喷枪顶吹熔炼技术是上世纪90年代由…     

银精矿碱法熔炼工艺的扩大试验

用正交试验法研究了熔炼温度、配煤量、配碱量及银精矿与铅精矿的质量比等因素对银精矿碱法熔炼中银、铅直收率的影响,建立了相应的回归模型;确定了苏打钾碱熔炼工艺的最佳工艺条件为：熔炼温度１０００～１０５０℃,停留时间１～２ｈ,配煤率４％～６％,钾碱率５％～７．５％及混矿比１∶１。此时,可获得含铅≥９８％,含银约１％的粗铅,铅、银的直收率分别大于９６％和９２％。     

高铅渣液态还原过程中有价金属分布

以铅精矿氧化熔炼产生的高铅渣为原料,通过静态实验研究其熔池熔炼还原过程。使用X射线衍射(XRD)和等离子体发射光谱(ICP)对反应原料及产物进行分析,探讨铁硅比、钙硅比、还原煤用量、还原温度、还原时间等对有价金属元素(Pb、Cu、Zn)在高铅渣还原产物中分布的影响。结果表明:静态实验中的Pb、Cu主要进入金属相,而Zn则基本进入还原渣中。最有利于有价金属综合回收的工艺条件如下:铁硅比1.25,钙硅比0.8,还原时间为60 min,还原温度为1200℃,还原剂的用量为理论量的1.3倍。     

大尺寸铅青铜铜板的铸造

在充分了解铅青铜(ASTMB584-938)的特性及铸件结构特点后,设计了合理的浇注系统,有针对性地制定了造型、熔炼及浇注工艺,克服了铅青铜厚壁件铸造容易产生重力偏析及气孔等问题,成功地生产出符合质量标准的铜板件.     

煤气熔炼反射炉爆炸实例

用煤气熔炼反射炉熔炼铝及铝合金时,过热铝液与含硫酸根过多的烟道灰发生作用会产生恶性爆炸。文中着重分析了煤气熔炼反射炉发生爆炸的原因,叙述了爆炸的简单过程及经验教训,并提出了预防措施。     

冲天炉熔炼节能减排的途径

对冲天炉熔炼过程中的熔炼环境、炉况状态、动力消耗等对能量损失的影响以及烟尘、噪声等污染物排放对环境的影响进行了分析;介绍了冲天炉附属设备、原材料及燃料选用、熔炼工艺及操作过程等方面的节能减排途径;指出适当配置装备、优化操作及合理选料和组织生产是实现冲天炉熔炼节能减排的基本措施。     

硫化铅矿闪速熔炼过程的热力学分析

基于最小吉布斯自由能原理,建立硫化铅矿闪速熔炼过程多相平衡热力学模型,考察熔炼温度(T)、吨矿氧量(VOVPTO)对粗铅含硫量、炉渣含铅量、烟气含铅量及铅在各平衡相中分配比的影响。结果表明:对一定用量和一定成分的硫化铅矿,随着T和VOVPTO的增大,粗铅含硫量可降至0.1%(质量分数)以下,但过高的VOVPTO会使渣含铅量升至60%(质量分数)以上,铅在粗铅中的分配比低于30%(质量分数);烟气中的铅主要以PbS形式存在,其含量随着T的升高及VOVPTO降低而增高。综合考虑铅的直收率及产物处理的难易程度,闪速炉直接炼铅应采取分区分步熔炼方式,先在氧化区制低硫铅,然后在还原区造低铅渣,且氧化区熔炼温度宜较低。     

胫骨生物陶瓷复合材料的微结构增韧机理

扫描电镜观察显示胫骨是一种由羟基磷灰石和胶原蛋白组成的自然生物陶瓷复合材料.羟基磷灰石具有层状的微结构并且平行于骨的表面排列.观察也显示这些羟基磷灰石层又是由许多羟基磷灰石片所组成,这些羟基磷灰石片具有长而薄的形状,也以平行的方式整齐排列.基于在胫骨中观察到的羟基磷灰石片的微结构特征,通过微结构模型分析及实验,研究了羟基磷灰石片平行排列微结构的最大拔出能.结果表明,羟基磷灰石片长而薄的形状以及平行排列方式增加了其最大拔出能,进而提高了骨的断裂韧性.     

Prospects of the Use of Synergetic Approach to Solution of Problems of the Science of Nanomaterials

A synergetic approach to solution of problems of self-controlled synthesis of nanostructures and creation of self-organizing nanotechnologies is considered in connection with the superproblem of creation of materials with functional properties resembling those of biosystems. __________ Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 55 – 61, July, 2005.     

Kinetics of the oxidation of metals — Influence of self-diffusion of metal

The importance of the self-diffusion of a metal during its oxidation by a gas is treated for the cases of nonstoichiometric oxides having either interstitial cation or cation vacancies. We have established a general relationship for the reaction rate when a mixed diffusion process occurs. From this relationship, we have shown that the pressure dependence can be different, according to whether the rate-determining process is the self-diffusion through the metal or through the product.     

Features of formation of the structure in production of blanks of disks of heat-resistant nickel alloys

Conclusions To provide a high level of mechanical properties in wrought blanks of cast ÉP741NP and ÉP962 alloys it is necessary to form controlled structures. A necklace-type structure formed in homogenizing isostatic treatment, subsequent thermomechanical working including alternation of the operations of deformation in the (+)-area and recrystallization anneals, and final heat treatment is preferable. The temperature conditions of all stages of thermomechanical working are strictly controlled, especially the final operation of deformation and heating for hardening. To eliminate hardening cracks and distortions it is necessary to use molten salts at t=600°C as quenchants. The use of multiple production operations makes it possible to significantly reduce the structural inhomogeneity related to inhertance of the original dendritic structure. However, the structure of the final semifinished product is nevertheless characterized by a difference in occurrence of the processes of polygonization and recrystallization between the former dendritic cells and the interdendritic spaces in deformation and heat treatment.To obtain structurally homogeneous blanks for gas turbine engine parts it is necessary to use basically new methods of remelting such as vacuum double electrode remelting and electron beam remelting with an intermediate vessel.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 12, pp. 25–29, December, 1991.     

Ab-initio calculation of enthalpies of formation of intermetallic compounds and enthalpies of mixing of solid solutions

A large number of ab-initio calculations of energies of formation of intermetallic compounds have been performed in the last 15 years. The currently used methods are listed. The paper presents a review of the aluminium based compounds which have been studied. Comparisons of calculated and experimental enthalpies of formation are provided for aluminim-3d and-4d transition metal alloys at equiatomic composition. The modelling of the enthalpies of mixing of solid solutions based on a given lattice is described.     

试论洋务派教师聘任的思想

洋务派在洋务学堂的办学活动中,为了解决西学专业学科的教学困难,采用了聘请外籍教师的应急措施.他们以真才实学,合同制管理作为主导思想,并认为这种解决师资的途径只是权宜之计,并非久远.从客观上看,洋务派的教师聘任思想有深刻的历史影响.