煤化工技术在钢铁行业的发展与应用

从钢铁行业的转炉煤气、焦炉煤气生产甲醇出发,总结了部分煤化工技术在钢铁领域的发展和应用。具体分析了固定床煤制气与气基法直接还原铁工艺、煤制气流化床与FINEX熔融还原铁技术、固定床与流化床结合的COREX熔融还原炼铁工艺、粗煤气余热冶炼直接还原铁工艺等,指出借助煤化工技术,可以提高能源利用效率,推动钢铁工业清洁生产。     

铜渣熔融还原炼铁过程研究

根据熔融还原原理,进行了铜渣熔融还原炼铁研究.考察了碱度、保温温度、保温时间、CaF2添加量对铜渣中铁收率和铁水脱S,P的影响.XRD分析结果表明,水淬铜渣中含铁物相主要为2FeO·SiO2和Fe3O4.确定的铜渣熔融还原炼铁的合理工艺条件为:惰性气氛下,碱度1.6,保温温度1 575℃,保温时间30min,CaF2/...     

熔融还原炼铁用耐火材料的研究现状

综述了国内外熔融还原炼铁用耐火材料的研究现状。讨论了熔融还原技术的工艺特，点及其耐火材料的使用条件。分析了目前已基本成熟的ＣＯＲＥＸ工艺的耐火材料的使用现状及存在问题，和铁浴式熔融还原炉用耐火材料的研究现状，存在问题及前景。     

熔融还原炼铁法用耐火材料的现状及其发展

熔融还原炼铁技术是当代世界冶金工业中引人注目的前沿开发技术之一，可以预料熔融不技术在本世纪末将有较大的突破，二十一世纪将有可能与高炉法并存而因地制宜地加以采用。由于熔融还原工艺的工作条件严酷，反应器的寿命很低，耐火材料的问题能否根本解决是决定熔融还原工艺能否投入使用的关键因素之一。本文讨论了两种较有发展前途的熔融还原工艺ＣＯＲＥＸ法和ＤＩＯＳ法及其所用耐火材料的现状，并预示了其发展前景。     

一步熔融还原炼铁流程的分析

本文对一步熔融还原炼铁流程进行了分析，考察了流程的能量分布情况，为一步熔融还原炼铁流程的节能和可行性研究提供了依据．     

超低碳炼铁技术路径分析

2060年碳中和目标既使我国钢铁工业未来发展面临巨大挑战，又为其提供了换道超车的发展机遇。本文对绿氢直接还原、氧化铁熔融还原、碱性溶液电沉积铁、酸性溶液电沉积铁的发展历史和技术现状进行了综述。在全绿电炼铁场景下，本文对各种技术路线的理论和实际耗电进行了估算，从技术成熟度、电耗、技术难度、应用前景等方面，对各技术路径进行了对比分析，发现碱性溶液电沉积铁电耗最低，酸性溶液电沉积铁和电供热氢气熔融还原次之。从技术难度上看，氢气直接还原、酸性溶液电沉积铁技术难度较小，且都已完成一定规模的中试，氢气熔融还原炼铁、碱性溶液电沉积铁和氧化铁熔融电解炼铁技术都还处于概念或技术发展早期阶段。综合来看，氢气直接还原、酸性溶液电沉积铁和氢气熔融还原炼铁路线可望发展成为有竞争力的超低碳炼铁技术，而碱性溶液电沉积铁和氧化铁熔融电解炼铁技术难度较大，短期内恐难以取得较大突破。     

石灰石对难选菱铁矿煤基熔融还原的影响

基于新型预还原-熔融还原一步炼铁工艺,以石灰石作为造渣剂,对新疆难选菱铁矿进行煤基熔融还原试验研究.探讨了石灰石在菱铁矿熔融还原过程中的作用机理及其掺量对铁收得率、渣铁分离效果、渣活性的影响规律.结果表明:石灰石对快速熔渣和熔融还原反应有促进作用,在一定范围内增加石灰石掺量有助于渣铁分离后铁收得率和渣活性的提高,随着石灰石掺量增大渣铁分离难度增大.     

基于节能减排思想分析炼铁工艺的发展

通过对中国炼铁产业现状进行分析,明确其在中国经济可持续发展中的重要性,指出由其所带来的严峻的能耗和环保问题. 基于钢铁企业的碳素流和能量流,分析了其节能减排的核心问题以及节能潜力点,认为炼铁系统的减排主要在于减少煤焦等含碳燃料的消耗,节能主要在于高效地利用炉顶煤气的显热和潜热,以及充分利用炉渣显热. 分析了当前较先进的炼铁系统节能减排技术,如喷吹焦炉煤气、喷吹塑料、全氧鼓风、高炉渣显热回收等,这些技术均是在高炉工艺基础上开发的,其普及程度对中国炼铁产业的节能减排至关重要. 展望了炼铁系统节能减排未来的研究方向,短期应深入研究燃料消耗机理,提高煤焦等燃料的利用效率,同时调整高炉系统能源结构,拓展更多清洁能源为炼铁系统所用,开源节流. 长期应深入思考炼铁系统碳脱氧还原的本质,着手新工艺的探索性研究,以从本质上改变炼铁工艺高能耗高排放的缺点.     

一步法熔融还原炼铁流程的模拟

本文对一步熔融还原炼铁流程进行了流程系统计算机模拟研究，建立了相应的通用程序软件．对不同煤种、铁矿石组成、铁浴炉渣碱度、铁浴出口温度及二次燃烧率等参数条件下的各项物料消耗、能量消耗及利用等指标作出了预报，并与二步熔融还原炼铁流程进行了物耗、能耗、成本等的比较，其结果可为该炼铁流程的概念设计提供依据和参考．     

流化床+铁浴熔融还原炼铁过程的分析

本文对流化床＋铁浴熔融还原炼铁流程进行了分析，从能量守恒以及能量贬质观点，综合评价和分析其用能过程，并绘出了全系统完整的流图，通过对薄弱环节分析，考察了流程的热力学完善性，并提出了一些相应的改善措施，为熔融还原炼铁流程的可行性研究及流程选择提供了依据.     

COMBINED TECHNOLOGY OF SMELTING REDUCTION IRON-MAKING AND CLEAN FUEL MANUFACTURE

Smelting reduction is a front iron making technology for the 21st century. It can produce liquid iron by direct using common coal but not charred coal. The process has many attractive advantages such as concise flow, low investment and production cost, low environmental pollution and high quality molten iron. Combined with a reciprocal chemical technology, energy efficiency can be further improved by transforming mass coal gas, by-produced in smelting reduction,into dimethyl ether, a clean fuel. Method and characteristics of the combined technology are discussed in this paper.     

Integration of coal pyrolysis process with iron ore reduction:Reduction behaviors of iron ore with benzene-containing coal pyrolysis gas as a reducing agent☆

An integrated coal pyrolysis process with iron ore reduction is proposed in this article. As the first step, iron oxide reduction is studied in a fixed bed reactor using simulated coal pyrolysis gas with benzene as a model tar compound. Variables such as reduction temperature, reduction time and benzene concentration are studied. The carbon deposition of benzene results in the retarded iron reduction at low temperatures. At high temperatures over800 °C, the presence of benzene in the gas can promote iron reduction. The metallization can reach up to 99% in20 min at 900 °C in the presence of benzene. Significant increases of hydrogen and CO/CO2 ratio are observed in the gas. It is indicated that iron reduction is accompanied by the reforming and decomposition of benzene. The degree of metallization and reduction increases with the increasing benzene concentration. Iron oxide can nearly completely be converted into cementite with benzene present in the gas under the experimental conditions. No sintering is found in the reduced sample with benzene in the gas.     

CLEAN PRODUCTION AND SMELTING REDUCTION TECHNOLOGY

Clean Production is the best method for iron-steel making industry to eliminate pollution thoroughly. In order to achieve this object, smelting reduction technology should play the key role. Furthermore, process integration method can be used to solve the problem of residual gas utilization by integrating smelting reduction process with direct reduced iron unit, gasoline, methanol or dimethyl ether synthesis unit, etc. A new smelting reduction process has been proposed which can be constructed on the present plant site. Since this process can directly treat the lump coal and iron ore fines, it reduces st6ps necessary in traditional blast furnace process and Corex smelting reduction process.     

神东烟煤中CaO在高炉喷吹中的作用及有价矸石排放减量化研究

根据神东烟煤CaO含量高的特点,通过试验研究煤粉中的CaO在高炉喷吹中的作用。研究结果表明,神东烟煤的高CaO含量特点可有效提高高炉风口区域煤粉的燃烧效率,同时减少高炉炼铁过程中助熔剂添加量,提高炼铁效率,降低生产成本。高炉每喷吹1 t神东高钙烟煤可为钢铁企业带来40~120元效益。同时,为实现煤炭利用价值的最大化,应根据钢铁企业用户需求,控制神东高钙烟煤的选煤深度,发展选择性选煤排矸脱灰技术,实现有价矸石排放减量化,减少排矸量,不仅有利于煤中有机组分的充分利用,而且有利于煤中灰分等无机组分的利用。     

Production of iron/carbon composite from low rank coal as a recycle material for steel industry

Utilization of low rank coal is indispensable to qualify the future demand of energy. Low rank coal, however, has several disadvantages such as small calorific value, so we should develop a new technology of using effectively it. On the other hand, as for the steel manufacturing process, we must think about an effective utilization of iron sludge and scrap from the standpoint of recycle. In this paper, we presented a new method to produce an iron/carbon material by utilizing a large amount of functional groups in low rank coal which can be used as an iron recycling media to revolving furnaces. The method is as follows: The low rank coal was oxidized for 2 h at 70 °C by nitric acid to introduce a large amount of carboxyl functional group and was impregnated by FeCl₃. Through pyrolyzing the Fe-impregnated coal pure iron crystal/carbon composite was successfully produced above 760 °C. As an option, Fe₂O₃ or Fe₃O₄/carbon composite was also successfully produced by the oxidation or gasification of it at low temperature. The irons in these composites were reduced by carbon with evolving CO and CO₂ at high temperature. Thus, it is clarified that the proposed method is attractive for producing a recycle material for the iron melting furnace prior to revolving furnaces from waste iron using low rank coal.     

钠修饰铁矿石载氧体的串行流化床煤化学链燃烧试验

利用1 kW_th串行流化床反应器对钠修饰铁矿石载氧体进行试验研究,考察燃料反应器温度对煤化学链催化燃烧特性的影响。结果表明,钠在820～920℃温度下显著促进了煤气化反应的进行,随着燃料反应器温度的提高,使用Na-铁矿石时燃料反应器出口CO₂浓度明显增大,CO浓度明显降低,在920℃时CO₂捕集效率和碳捕集效率分别达到78.60%和80.54%,而使用纯铁矿石时CO₂捕集效率和碳捕集效率仅为40.27%和45.65%。在高温950℃时Na-铁矿石活性下降,出现烧结和团聚现象,燃料反应器出现滞流态化现象,这可能是钠的化合物熔点较低和载氧体过度还原所导致的。XRD和SEM分析结果显示钠修饰铁矿石促使更多的Fe₂O₃被还原为Fe₃O₄。     

烧结铁矿的低温还原粉化

以连续性煤气升温模拟高炉生产过程,研究烧结矿的粉化行为,考察了煤气成分对烧结矿低温还原粉化的影响. 结果表明,可将烧结矿在高炉内的低温还原粉化过程分为3个阶段,粉化最剧烈的是第二阶段(400~600℃),此阶段烧结矿粉化指数达50.2%,占整个还原阶段粉化指数的48.5%,还原度却只有15.39%,占整个还原度的17.9%,中值粒径为3.91 mm. 增加还原煤气中的H2比例可增加烧结矿的粉化指数,但增加幅度逐渐降低;增加还原煤气中CO2比例可降低烧结矿的粉化指数,但降低幅度逐渐减小.     

煤矸石/粉煤灰对赤泥钠化还原焙烧反应的影响机制

煤矸石或粉煤灰与赤泥协同钠化还原焙烧均可实现其所含铁、铝、硅等元素的形态转化,使其易于分离回收;但对于它们分别与赤泥协同钠化还原焙烧反应差异性及机制的研究目前尚未见报道。采用X射线衍射分析方法,分别考察了煤矸石-赤泥、粉煤灰-赤泥体系钠化还原焙烧过程中,气氛类型、钠助剂添加量、焙烧温度、焙烧时间对还原焙烧产物物相组成的影响规律,并对两个反应体系中铁磁化效果及铝硅活化效果的差异性进行分析。结果表明：在钠化还原焙烧过程中,煤矸石-赤泥、粉煤灰-赤泥体系均可同步实现含铁物相的磁化和铝硅物相的活化,且随着钠助剂添加量、焙烧温度、焙烧时间的变化,含铁物相和铝硅物相呈现规律性变化;在相同铁磁化和铝硅活化效果前提下,煤矸石-赤泥体系所需钠助剂添加量、焙烧温度和焙烧时间均略低于粉煤灰-赤泥体系,这主要与煤矸石、粉煤灰中所含还原性物质和铝硅矿物的赋存形态、含量及微观结构有关。研究将为煤矸石、粉煤灰等煤基固废与赤泥协同钠化还原焙烧回收有价元素的原料筛选提供理论指导。     

洁净煤制取还原气技术生产海绵铁[上]

分析了BL法直接还原生产海绵铁工艺的特点,介绍了新型多喷嘴对置式水煤浆气化技术工业实践与技术的特点,提出了新型多喷嘴对置式水煤浆气化技术生产海绵铁并联产化工产品的设想。该技术对煤种适应性广,比其他煤基炼铁方法减少排放CO240%、NOX86%、SO281%。