废槽衬无害化处理工业示范厂运转结果

本文介绍了我国首家废槽衬无害化处理工业示范厂的运转情况,重点探讨了反应温度、生料停留时间对废槽衬无害化处理工艺的影响。反应温度足够高,生料停留时间足够长,废槽衬无害化反应越彻底,熟料中F-含量越低,固体渣质量越好。工业示范线运转结果表明,采用合理的工艺制度、配入有效的反应药剂,可实现废槽衬的无害化处理,得到无害的、分散性好的固体渣。     

电解铝废槽衬处理技术的最新研究

废槽衬是电解铝工业定期排出的危险废物,是国家明令禁止随意丢弃的Ⅰ类废物.跟踪监测了某铝厂的废槽衬堆场,监测结果表明:废槽衬的有害物质将随雨水逐步向土壤和地下水中转移,两年时间内有54％的可溶氟化物转移进入了土壤和地下水.分析了目前四种较为成熟的废槽衬处理技术,对比了其可行性和实用性,为我国全面开展电解铝废槽衬的处理提供了借鉴.     

铝电解废槽衬中毒害物质足迹（英文）

铝电解废槽衬(SPL)因其含有大量可溶性氟化物和少量剧毒氰化物而被列为危险固体废弃物。对运行了2396天的350kA铝电解槽中氟化物和氰化物的分布状况进行检测分析,研究废槽衬中毒害物质的足迹和腐蚀机理。研究结果表明,氟化物主要集中在阴极炭块和阴极下方的干式防渗料层中,这与氟化物在此区域的渗透状态密切相关。氰化物浓度在电解槽中部位置较低,而侧壁高浓度的氰化物与进入电解槽内该区域的空气量呈正相关。     

电解槽废槽衬现状处理及技术分析

电解废槽衬属危险固体废渣,对环境影响很大,随着国家对环境保护和节能减排力度的不断加强,对电解铝废渣进行无害化处理将是电解铝企业履行社会责任所必须,也是企业可持续发展所必行.简要分析了我国电解铝生产中所产生的废槽衬的危害及污染现状,并对国内外电解槽废槽衬现状处理及技术分析进行了探讨.     

中国首条铝电解废槽衬无害化处理线投运

正中国铝业公司首条铝电解废槽衬于2017年4月10包头铝业有限公司顺利投产,标志着中铝公司对铝电解槽大修产生的危险废弃物无害化处理技术达到先进水平。该项目的废槽衬处理能力为10kt/a,可全部处理完包头铝业公司目前有量及未来产生的电解槽废衬料。实验证明,处理后的废槽初氟化物浸出浓度≤6ng/L,远远低于GB中的100mg/L值,属于Ⅰ类一般固     

铝电解槽废内衬的高温水解

多年来,凯撒公司、鲁奇公司和联合铝业公司一直在共同研究使用膨胀循环沸腾层处理电解槽废内衬的高温水解方法(实验规模)。利用废内衬中含有的碳回收电解槽废内衬中所     

提高铝厂经济效益的几项措施

本文从理论和实际上说明降低铝用阳极净消耗(Nc)会提高电流效率(CE)、增加铝产量(P)、降底电耗(W)和提高阳极使用周期；延长槽平均寿命可降低槽大修费用、焙烧和启动费用、增加铝产量、提高铝质量、减少停槽期间电流空耗和减少废内衬对环境的污染；采用刨炉机刨炉以缩短槽大修周期。采用上述措施会提高铝厂经济效益。     

280kA大型预焙槽内衬优化及槽寿命的研究

内衬优化和槽寿命研究是铝电解技术的一个重要课题，本文就基地280kA电解槽生产现状进行剖析和研究，提出母线和内衬优化是改善280kA电解槽炉帮形成和提高槽寿命的根本途径，完好的焙烧启动过程和合理的启后管理及完善的技术条件是电解槽高效运行延长槽寿命的根本保障。     

努力寻找处理废旧电解槽内衬的方法

铝电解厂的电解槽内衬有5～8年的预期使用期限，但是在它的使用期限完毕之后，由于它含有诸如氟化物和氰化物之类的有毒物质，如何对这些废旧槽衬进行安全处理成了问题。     

处理盐渣的ENGITEC系统

再生铝行业是指从外形和成分上对各种废铝进行回收。废料经过分选、调配、混杂、熔解，然后精炼成各类规格的合金。在欧洲，转炉通常用做废铝的熔解。在熔解过程中，将主要成分为氯化钠或氯化钾的溶剂放在溶解槽中，以此减少金属氧化，并清除所排放的杂质。所形成的盐渣含盐剂、少量铝金属、铝氧化细渣和水铝反应混合物。     

An Overview of Useful Methods to Treat, Recover, or Recycle Spent Potlining

A summary of the state of the art of the processes used to reduce the toxicity and/or recycle spent potlining (SPL) is presented including some industries (cement, rockwool, and steel) that accept quantities of SPL. The authors have concentrated on processes that either are still active or have been developed to a pilot or preindustrial stage and have provided references to allow the reader to access other useful processes.     

WC/W_2C_P在NiCrBSi合金中的分解机理及其表面渗碳改性

为了抑制铸造碳化钨颗粒(WC/W2C P)在复合材料制备过程中的过度分解,利用SEM、EDS和XRD等测试手段对WC/W2C P在Ni Cr BSi合金中的分解机理及其表面改性渗碳处理进行了研究。结果表明,铸造碳化钨由WC和W2C两相组成,在Ni Cr BSi合金中WC相比W2C相具有更好的化学稳定性。在熔烧法制备WC/W2C P增强Ni Cr BSi基复合材料涂层的过程中,基体熔液和WC/W2C P发生元素互扩散;WC/W2C P中的化学稳定性差的W2C相与从基体熔液中扩散过来的Ni、Cr等元素反应生成了富W、Ni的碳化物,而化学稳定性好的WC相几乎完整的保留下来;基体中的Ni、Cr元素与从WC/W2C P中扩散过来的W、C元素形成了富W、Ni、Cr的碳化物在凝固过程中析出。经渗碳表面改性后,WC/W2C P表面形成了化学稳定性好的WC壳层,该壳层能有效抑制WC/W2C P在基体中的扩散分解,减少基体中碳化物的析出。     

INFLUENCE OF RARE EARTH ON INTERGRANULAR CRACKING OF 9% Ni CAST STEEL

The intergranular cracking of 9% Ni cast steel seems mainly to relate to the segregation ofcontaminates H,S and P along boundaries.An addition of rare earth may eliminate the seg-regation of these contaminates along grain boundaries and improve the binding force amongboundaries,so as to reduce remarkably the intergranular cracking.     

Carbothermic reduction of chromite fluxed with aluminum spent potlining

Aluminum spent potlining (SPL) was employed as both the fluxing agent and a source of carbonaceous reductant for the carbothermic reduction of chromite, aiming to allow effective separation of alloy from the slag component. The experimental results show that the carbonaceous component of the SPL is more reactive towards chromite reduction compared to graphite. The formation of refractory spinel (MgAl₂O₄) on chromite particles hinders further reduction and alloy growth. The slag-making components of the SPL (e.g. nepheline and NaF) form molten slags at low temperatures (～1300 °C) and partly dissolve the refractory spinel as well as the chromite. Destruction of the spinel layer with enhanced mass transfer greatly improves the alloy growth, which can be further promoted by reduction at a higher temperature (e.g. 1500 °C). Ferrochrome alloy particles grow large enough at 1500 °C in the presence of SPL, allowing effective separation from the slag component using elutriation separation.     

Environment protecting hydrometallurgical processes associated with the manufacture of some tungsten based products. II. Dissolution of the molybdenum mandrel wire from tungsten coils

The basic hydrometallurgical operation of the tungsten filament manufacturing, the molybdenum mandrel wire dissolving has been reviewed from environmental and hygienic aspects presenting the published efforts for streamlining of the traditional H₂SO₄---HNO₃ mixture based process.

The fundamentals of a new environment-preserving and hygienic process based on H₂O₂-catalyst mixture are outlined as well as its development and industrial implementation to a zero effluent discharging process and equipment consisting of selective molybdenum dissolving from tungsten coils and the recovery of the dissolved molybdenum and process water.

Some desirable development potentials of the new process are sketched considering scientific, technical, economical and environmental aspects.     

热水器内胆焊缝热影响区缺陷分析

对热水器内胆进行水压测试时,水管环焊缝周边开裂是导致产品不合格的主要因素,给企业带来较大损失。以某品牌热水器内胆为研究对象,借助扫描电镜、金相显微镜和宏观观察等检测手段探讨并分析出现水压开裂的原因。研究表明,热影响区在焊接前受到塑性变形,易形成应力集中,存在摩尔形变储存能Es,在受到焊接热输入时,该处晶粒易发生再结晶并逐渐长大,形成粗大晶粒,导致水压测试时焊缝出现裂缝甚至断裂。     

A method of etching and powder blasting for microholes on brittle materials

Brittle materials such as semiconductors, ceramics, glasses, piezoelectric etc., are difficult to machine by traditional machining methods. This paper provides an approach to create holes or grooves more efficiently via powder blasting process. Instead of one protective layer for mask that is conventionally used, two layers are coated on the surface of the substrate material. The inner layer is water-soluble resin with excellent adhesion to the substrate but having weak resistance to powder erosion, and the second layer is a photosensitive oligomer that is adhered well to the first layer and has very high resistance to powder erosion. Such a protective coating possesses two contrary characteristics: high resistance to powder blasting and easy removal from substrate after powder erosion. Once the openings of the second layer are formed at the desired positions via a photo-etching method, a printing method, or other methods, the holes or grooves can be obtained by etching through the openings of the second layer to the first layer and the substrate by a powder blasting process. Then the whole protective coating is easily and smoothly stripped off without any damage to the substrate by dissolving the first layer with water. Due to easy removal of the mask plus the good resistance to powder blasting and a much higher erosion rate than the one obtainable by wet and dry etching processes, the proposed process can be applied to create holes or grooves on brittle material, instead of chemical etching process, so as to achieve a good quality and superior rate of production.     

蘸水笔刻蚀技术(DPN)影响因素分析

蘸水笔技术(Dip-Pen)是近年来发展起来的一种新的扫描探针刻蚀加工技术,有着广泛的应用前景.该技术是直接把弯曲形水层作为媒介来转移"墨汁"分子,在样品表面形成纳米结构.尖端曲率半径、针尖在基底表面滞留时间、针尖扫描速度、空气湿度、表面粗糙度等均会影响纳米结构的线宽.针尖在基底表面滞留时间与圆半径的平方成一次函数关系,线宽随着尖端半径的增大而变宽,扫描速度与线宽成反比关系.通过控制湿度可以控制"墨水"分子的转移速度,从而影响纳米结构的线宽.线宽随着样品表面粗糙度增加而变宽.