RH浸渍管粘渣形成原因及解决办法

通过成分和物相分析,探讨了硅钢冶炼过程RH浸渍管表面粘渣的形成原因,提出优化RH精炼渣成分的改进措施并开展了生产试验进行验证。结果表明:粘渣成分与RH终点渣成分相似,主要由Al_2O_3,CaO,Fe_xO_y,SiO_2和MgO等组成,形成的主要物相为铁铝尖晶石和钙铝黄长石;粘渣由高黏度、高熔点的RH精炼渣粘附在浸渍管上不断累积长大形成;增加RH炉渣中CaO含量,提高炉渣中CaO/Al_2O_3的含量比值,可降低炉渣的黏度和熔点,避免浸渍管表面粘渣的形成和长大。     

活性石灰在钢水精炼中的应用

介绍了在钢水精炼过程中，添加一定量的活性石灰和萤石，提高精炼钢水顶渣的碱度，降低熔渣的熔点，改善熔渣的流动性。消除钢包内衬结渣挂渣、顶渣结壳的现象，以及AHF浸渍罩、RH上升管和下降管结渣上涨的现象。同时钢水精炼添加活性石灰后，有一定的脱硫和吸附一定量钢中夹杂物的作用。     

调质剂对 LATS 精炼渣熔点与脱硫能力的影响

为减少LATS-OB精炼浸渍罩粘渣及提高浸渍罩寿命,分别用CaO-CaF₂、CaO-B₂O₃及Li₂O作为钢包渣的调质剂进行调质实验。熔渣半球点法的熔点测试结果表明,采用CaO／CaF₂=1或2,CaO／B₂O₃=1或2和Li₂O作调质剂能显著降低钢包渣的熔点;渣-金平衡试验表明,调质后的钢包渣可使钢中的硫含量进一步降低。     

RH真空室加渣对熔池内渣钢间传质影响的水力学模拟

在RH真空精炼中,覆盖渣处于大包熔池内的弱搅拌区,渣钢反应很弱,对依靠渣钢反应去除硫等有害元素或吸附钢水中夹杂物有很大的影响,降低了精炼效率。为了提高除硫等精炼效率,利用水模拟钢水,机油模拟渣,苯甲酸模拟渣-钢间传输物质来研究RH装置真空室内加渣时的加渣量、吹气量和浸渍管插入深度对渣钢传质的影响。试验结果表明,采用真空室内加渣方法渣钢之间的容量传质系数提高了60～130倍,大大提高了渣钢传质速度,为实际生产中通过真空室内加渣加强渣钢传质以提高除硫等精炼操作提供了理论依据。     

RH精炼过程非金属夹杂物

 以200t钢包RH精炼装置为原型建立了1∶5水模型,分析了实际工艺条件下RH上升管吹气量对卷渣的影响。结果表明,当上升管吹起量为120m3/h时,发生平稳、均匀的卷渣,有利于钢渣反应,根据水模型结果在RH上进行了试验,并通过系统取样,采用金相显微镜、图像分析仪和扫描电镜对比研究了用和不用预熔渣处理的无取向硅钢在精炼过程的夹杂物的数量、尺寸分布以及夹杂物的类型演变情况。经过定量比较发现,在有预熔渣的情况下,RH真空处理后,钢中Al2O3夹杂物变性为CaO-MgO-A12O3的复合夹杂物,并且夹杂物数量和尺寸明显变小。     

涟钢RH-MFB精炼渣系研究

对涟钢HMPT-BOF-RH-MFB-CSP单联工艺生产SPHE钢时RH精炼过程中精炼渣进行取样分析,研究表明:随精炼过程的进行,RH精炼渣系的熔点呈下降趋势；但氧化性增强,致使不少炉次在RH精炼阶段存在“回硫”现象；并且,在RH精炼脱碳过程炉渣Al2O3含量在逐步增加,RH精炼结束时,炉渣中Al2O3含量在27％～37％,不利于吸收钢液中上浮的Al2O3夹杂物.为此提出了RH较为合理的终渣系目标控制范围.     

CaO-SiO2-Al2O3-CaF2系精炼渣对钢绞线用 SWRH82B钢中D类夹杂物的控制研究

通过钢渣平衡实验研究,分析了精炼渣成分对82B钢液T.O和点状不变形夹杂物成分的影响;通过Fact-Sage热力学计算,得出硅锰脱氧82B钢中MgO·Al₂O₃尖晶石夹杂的生成条件.结果表明:降低精炼渣碱度、提高Al₂O₃含量均利于钢水全氧含量的降低;随着Al₂O₃含量的提高,复合氧化物夹杂的熔点升高.当熔渣碱度为0.93、Al₂O₃含量为5.1%时,夹杂物熔点最低;熔渣碱度为1.14、Al₂O₃含量为25.6%时,高Al₂O₃活度的熔渣导致MgO·Al₂O₃尖晶石夹杂生成;熔渣碱度为1.97、Al₂O₃含量为25.9%时,由于碱度升高,钢中无MgO·Al₂O₃尖晶石类夹杂物生成;熔渣碱度为0.93、Al₂O₃含量为5.1%时,由于Al₂O₃含量降低,钢中无MgO·Al₂O₃尖晶石类夹杂物生成,且夹杂物熔点较低.      

GCr15轴承钢RH和VD真空精炼过程钢洁净度对比

摘要：对比了RH和VD真空精炼工艺生产的GCr15轴承钢精炼过程的洁净度水平,研究了钢液中总氧（TO）、总氮（TN）、总硫（TS）以及夹杂物变化规律。轴承钢对洁净度要求较高,RH精炼工艺在降低钢中TO、TN含量,固相夹杂物去除,循环效率上均具有优势。经过RH精炼后,钢液中TO含量下降了61%,TN含量下降了15%,夹杂物数密度降低了75%;VD精炼过程中,钢渣反应剧烈,脱硫效果优异,VD精炼后钢液中TS含量下降了50%,但钢液循环速率远落后于RH精炼,且更容易发生卷渣。不同液相分数的夹杂物与钢液的接触角不同,液相分数小于27%的夹杂物与钢液不润湿,容易碰撞长大和上浮去除,而液态夹杂物黏附功更大,难以从钢液中去除。     

LF深脱硫钢种钢包结壳分析及控制方法

为了解决LF深脱硫钢种钢包顶渣结壳的问题,对结壳炉次精炼渣成分及熔点进行分析,利用扫描电镜对结壳物进行微观形貌及物相研究.结果表明,由于炉渣熔点过高,冷却过程中析出物呈网状联结导致顶渣结壳.根据相图确定了降低熔点的精炼渣改质目标区域,基于渣量核算提出了两种优化后渣改质工艺方案,通过工业试验验证,优化后精炼渣可同时满足L...     

1000MW级汽轮机转子锻用钢精炼渣系的设计

针对1 000 MW级汽轮机转子锻用钢的低硅低铝和钢种夹杂物要求高的特性,对LF精炼和VD真空精炼熔渣进行了研究。结合相图,并通过渣样分析,发现采用CaO、CaF2作造渣材料,精炼渣位于高熔点区域。真空处理前在新设计的精炼渣系中添加5.0~6.0 kg/t的硅石,通过降低碱度来改善精炼渣的性能。真空处理后精炼渣处于低熔点区域,吸附夹杂物的能力强。新设计的精炼渣冶炼的百万千瓦级汽轮机转子锻用钢非金属夹杂物≤1.0级。     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.