含磷钢渣碳热还原脱磷及资源化利用的研究现状

摘要：针对脱磷转炉渣中磷资源高效回收及其资源化利用过程中存在的问题,系统总结了含磷钢渣除磷方式及其应用优缺点,并着重总结了不同条件（炉渣温度、炉渣碱度、钢渣中FeO质量分数、碳当量、底吹气体流量、冶炼时间等）对碳热还原气化脱磷的影响规律。同时,以应用前景较好的碳热还原气化脱磷方法为基础,提出了脱磷转炉渣在碳热还原气化脱磷过程磷的流向规律,展望了渣中磷资源回收制备磷铁及其循环利用模式。这为实现渣中磷资源高效回收及处理后残渣资源化利用提供重要研究基础和方向。     

真空碳热还原-酸浸含钛高炉渣制备TiC

中国超过50％钛资源在高炉冶炼过程中进入炉渣,渣中TiO2的质量分数高达20％～30％,是一种高附加值二次资源,但在对该资源综合利用过程中,始终未能解决经济提取、硅钛难分,二次污染严重等问题.在热力学理论指导下进行真空碳热还原-酸浸联合工艺处理含钛高炉渣制备TiC研究.研究表明,碳热还原温度越高或相同温度下真空度越高越有利于炉渣中各成分还原;随着真空度增加碳热还原温度要求降低;当温度达到1 573K,真空度为1 Pa,可将SiO2还原得到具有高蒸气压的SiO、MgO被还原为Mg蒸气而离开体系,可实现渣中硅镁与钛彻底分离;真空碳热还原含钛高炉渣制备TiC的最佳条件:还原温度1673 K,炉渣粒度75μm占80％,渣碳质量比100∶38.     

转炉熔渣气化脱磷时磷迁移规律研究

气化脱磷能够有效地去除熔渣中部分P2O5,扩大其磷容量.在实验室进行了焦炭还原转炉渣气化脱磷热态试验,热力学计算研究结果表明,在1540℃下焦炭会优先还原P2 O5,还原产物为可能的P2,而P2 O5的实际还原率与理论计算值基本一致.通过SEM-EDS对还原前后炉渣形貌进行分析,转炉终渣主要由C2 S相、RO相、钙铁橄...     

熔融改质含磷钢渣碳热还原回收有价元素试验

 针对含磷转炉渣中磷、铁及锰等有价资源回收及有价元素回收后钢渣资源化利用的问题,通过理论计算、电阻炉试验、感应炉试验等研究手段,系统分析了熔融改质后的含磷钢渣碳热还原回收有价元素的热力学条件和影响规律。研究结果表明,还原温度为1 723 K、碱度为1.0~2.0时,低碱度有利于渣中铁、磷资源的回收;当炉渣碱度为1.0时,Fe₂O₃、P₂O₅、MnO还原率分别可达到99.50%、84.47%和3.26%,渣中铁元素和磷元素收得率分别为99.50%和68.69%;当碱度为1.5时,渣中Fe₂O₃、P₂O₅还原率分别为90.45%和63.73%,与碱度为1.0时相比还原率降低;当碱度为2.0时,渣铁未实现完全分离,渣中Fe₂O₃还原率为71.43%。在感应炉内对熔融改质工业渣碳热还原试验中,在碱度为1.0时,温度为1 723 K条件下,渣中铁元素收得率可以达到99%以上,磷收得率为47.18%;通过热力学分析可以发现,FeO、P₂O₅与MnO相比更容易被碳还原,在试验过程发现,FeO及P₂O₅先还原,反应20 min后渣中MnO开始被还原,整个还原过程中渣中MnO含量略有降低;碳热还原后渣中FeO质量分数仅为0.07%,渣中P₂O₅质量分数为0.93%,MnO质量分数为2.83%;利用FactSage对比改质渣还原前后物相组成可知,还原后渣中含铁物相(Ca₃Fe₂Si₃O₁₂)物相能得到有效控制,磷酸钙质量分数明显减少,渣中橄榄石相大幅度增加,提高了钢渣的应用范围,这为含磷钢渣有价元素回收及资源化利用提供了研究基础。     

转炉渣中氧化磷对铁水脱磷影响的研究

以转炉渣为基础渣,在实验室测定了CaF2、P2O5质量分数变化对转炉渣熔点的影响。依据测定结果,利用转炉渣配制适合铁水脱磷要求的脱磷剂进行了铁水预脱磷实验,结合相关的转炉脱磷研究结果,分析了脱磷剂中P2O5对脱磷的影响,提出了对最终外排炉渣中的质量分数要求。在1350 ℃温度条件下,w（P2O5）＝166％转炉渣为基础的脱磷剂,对预脱硅处理后的铁水,脱磷剂加入10％时可取得约77％的脱磷率。脱磷剂中w（P2O5）＜75％时可取得60％以上的脱磷率。     

用碳热还原法从含钒钢渣回收含钒生铁

实验研究表明对于含钒2．65％钢渣,钒元素主要分布在RO相和Ca3SiO5相中;调节渣中（CaO／SiO2）=2,含V2O53．4％的合成渣,熔化缓冷后,钒主要固溶于Ca3SiO5相中;对于V2O5含量在4．7％-7．0％之间的钢渣,钒是以CaV2O6还是Fe—Mn—V—O固溶体形式存在主要取决于渣中铁氧化物的含量。在钒含量较低的钢渣中,由于含钒相的晶粒较小,很难将钒从其它组分中分离出来,但在1550～1600℃条件下,用碳热还原法可以有效地回收钢渣中的钒,得到被碳饱和的钒铁合金,利用渣在冷却过程中自动粉化现象,很容易实现渣和合金的分离。     

气化脱磷机理及对下炉次冶炼过程的影响研究

为了解决转炉渣由于磷含量过高而不能返回到转炉内循环利用的问题,采用FactSage7.2并结合SEM+EDS对气化脱磷理论和影响因素、留渣操作和枪位控制对脱磷的影响以及气化脱磷渣形貌进行了分析。结果表明,在温度高于941 K时用C还原出炉渣中P_2O_5的P是可行的,同时降低反应分压有利于气化脱磷反应的进行;采用焦粉作为还原剂时,碳当量和底吹流量分别控制为2倍碳当量和300 m~3/h时气化脱磷效果最好;当底吹流量为300 m~3/h、2倍碳当量和w(FeO)≥18%时气化脱磷率最高,为42%。采用留渣操作溅渣护炉气化脱磷模式时终点钢液磷含量较低,前期采用稍高的吹炼枪位,后期逐渐降低枪位,气化脱磷渣形貌结构表明P元素主要富集在Ca、Si所在的深灰色区域。     

硅还原转炉熔渣气化脱磷实验研究

在1773～1973 K温度范围内,满足溅渣护炉的炉渣条件下,在真空碳管电阻炉中对转炉渣进行了硅热还原实验研究.结果表明,在影响还原脱磷的因素中温度的影响最大,FeO含量次之,再次是氮气流量,炉渣碱度影响最小.研究确定了适宜溅渣护炉气化脱磷的最佳条件,还原炉渣气化脱磷率最高可以达到81.23%.     

转炉热态熔渣脱磷及循环利用生产实践

为去除转炉渣中的磷,实现转炉渣在转炉内的循环利用,从而达到降低冶炼成本的目的,针对顶底复吹转炉炼钢生产,结合气化脱磷热力学理论分析,研究了不同因素对脱磷率的影响。结果表明,在炼钢温度下用碳质脱磷剂还原炉渣中P2O5是可行的,选择碳质还原剂更合理。转炉熔渣脱磷率与熔渣温度、还原剂加入量、渣中FeO质量分数存在明显关系,3个参数的取值分别为1 660～1 670 ℃、150～200 kg和20%时,熔渣的脱磷率可以达到30%以上。生产实践表明,转炉熔渣的炉内循环利用可以降低石灰消耗3.29 kg/t、钢铁料消耗2.94 kg/t、炼钢成本5.48元/t。     

含钛高炉渣碳化及超重力分离碳化钛的研究

以热力学计算为依据,研究在焦炭还原攀钢含钛高炉渣的过程中,反应温度和保温时间对碳化钛的生成量的影响,同时利用超重力技术来分离还原产生的碳化钛.研究结果表明:含钛高炉渣经高温碳热还原后得到有价组元碳化钛,当实验温度设定在1 600 ℃保温5 h时,还原渣中碳化钛的含量最高,熔渣中钛氧化物转化为碳化钛的转化率达到最佳.另外,还原渣经超重力分离后碳化钛被截留在碳毡上部的精矿中,脉石相则被分离到下部坩埚中,还原渣在重力系数G=300于1 320 ℃等温分离20 min后,精矿中碳化钛的含量由还原渣中的12.1 %提高到26 %,通过超重力技术可以使碳化钛含量提高一倍多.      

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.     

Seven Rare Earth Projects Involving Close to 3 Billion Yuan Investment Landed In the HighTech Zone

正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.