COREX竖炉炉顶安装机械探尺的分析

文章对COREX-3000竖炉顶改装为机械探尺测料线进行分析.介绍了机械探尺的尺寸,机械探尺的工作环境,机械探尺在竖炉顶的安装位置.通过与八钢2500m3高炉机械探尺的对比分析,认为在COREX炉顶安装机械探尺是可行的.     

COREX预还原竖炉煤气停留时间分布的数值模拟

为研究COREX预还原竖炉内煤气流动特性,利用数值模拟方法研究了炉内煤气停留时间分布（RTD）,考察了AGD（Areal Gas Distribution）梁对COREX预还原竖炉炉内RTD的影响以及不同熔炼率下COREX预还原竖炉的RTD变化规律.模拟结果表明,随着2#COREX预还原竖炉AGD梁的安装,其整体时间密度分布函数变宽,平均停留时间变短,无量纲方差变大.AGD梁的安装增大了炉内的死区体积分数,2#COREX预还原竖炉炉内死区体积分数达到了26.81%.随着竖炉熔炼率的增加,炉内平均停留时间逐渐减小,无量纲方差逐渐增大.当熔炼率从150 t/h增长到180 t/h时,1#COREX竖炉死区体积分数降幅为68.1%,2#COREX竖炉降幅仅为15.52%.     

COREX煤气中H2含量的对比分析

宝钢2#COREX投产后各技术经济指标持续改善,竖炉金属化率稳定在85%以上,冷煤气中H2含量比1#COREX高出2个百分点,但竖炉炉顶煤气中H2含量相差很小。基于COREX工艺过程中H2含量变化的理论解析,分析了氢元素的守恒、海绵铁金属化率、拱顶温度和竖炉还原对H2含量的影响。研究结果表明,冷煤气中H2含量的增加主要由竖炉海绵铁金属化率的提高所致,且随着竖炉金属化率的提高,气化炉运行更稳定,料柱温度升高,气化炉用氧分配趋向合理等冶炼特征发生改变。     

COREX炼铁煤气生产热压块流程的模拟分析

COREX熔融还原炼铁工艺采用非炼焦煤直接炼铁,缩短了工艺流程,减轻了炼铁工业对环境的污染,生产过程产生的大量优质煤气可以用于生产热压块 .1套COREX C2000装置输出的煤气量和1座年产0.8 Mt的直接还原设备所需要的还原煤气量大致相当.对利用COREX炼铁煤气生产热压块的工艺能量利用进行了分析,指出了竖炉还原过程中的适宜条件和影响因素.     

Minimization of Exergy Losses in the COREX Process

The COREX process is being projected as an alternative for blast furnace iron making. The coal consumption of the COREX process is large with a net fuel rate of ~1000 kg/tone of hot metal (THM). The reason for a higher net fuel rate of the COREX process compared with the net coal rate for the blast furnace process has been investigated. Exergy analysis has been performed for identifying the causes, locations, and magnitudes of process inefficiencies for the COREX process. Whereas blast furnace process data are available in the literature, no systematic data for stream information of the COREX process are available for different input coal rates required for exergy computation. A composite model of the COREX process (i.e., models for the smelter gasifier and the reduction shaft) using FactSage 6.2 (Thermfact/CRCT, Montreal, Canada, and GTT Technologies, Aachen, Germany) is used to generate stream data. A new methodology for the calculation of exergy of the COREX process streams using the database in FactSage is proposed in this work. Exergy data for blast furnace process streams have been obtained from the literature. The exergy loss and exergy efficiencies of the COREX process are evaluated at various coal rates and compared with those of the blast furnace. Operating the COREX process is theoretically feasible at lower coal rates with higher exergy efficiencies when lesser export gas is generated.     

含碳球团-铁浴熔融还原炼铁法与COREX法的能耗比较

通过计算机模拟计算,研究了含碳球团高温快速预还原＋铁浴终还原炼铁法、含碳球团竖炉预还原＋铁浴终还原炼铁法和含碳球团铁浴一步炼铁法这３种工艺流程的能耗,并与ＣＯＲＥＸ法进行比较。结果表明：含碳球团＋铁浴终还原炼铁法比ＣＯＲＥＸ法的耗煤量和耗氧量低。另外,还介绍了高含碳球团的优点,认为高含碳球团有一定的应用前景     

八钢1#COREX炉顶煤气喷雾降温系统特点

文章介绍了八钢1#COREX工程顶煤气干法除尘改造项目.为配合干法除尘工艺顺利实施,在竖炉顶部及重力除尘器中部加装两套雾化打水装置,以满足COREX竖炉顶煤气降温需求.主要介绍顶煤气喷雾降温系统主要技术性能及应用.     

COREX竖炉炉料黏结的机理研究和影响因素分析

竖炉内炉料黏结是COREX炼铁工艺中的一个重大难题,国内外COREX生产操作都表明预还原竖炉内部的炉料容易黏结成块或黏结在竖炉的炉墙上,累积到一定程度后,会引起竖炉悬料,影响COREX还原煤气的利用和预还原竖炉的顺行,严重时甚至堵塞竖炉,使还原煤气难以接受或无法排料而被迫清空竖炉。在竖炉清空期间,对竖炉内黏结物进行了取样和分布情况调查,借助于化学成分检测、SEM和XRD等手段,分析了竖炉内黏结物形成的机理。在上述分析的基础上,通过实验室的试验研究考察了竖炉内炉料黏结的影响因素,结果表明,温度、金属化率、挤压时间、煤气成分等是黏结的主要影响因素。     

现代炼铁技术进展

评述了国际上发展较快的几种主要非高炉炼铁工艺流程.COREX、FINEX和HISMELT等熔融还原流程可以避免炼焦工艺引发的环境污染.成熟的竖炉气基还原工艺是COREX流程工业化的重要保障,粉体流化床由于粘结等问题尚未完全解决和铁浴炉二次燃烧与炉衬侵蚀之间的固有矛盾注定了FINEX和HISMELT实现的难度远高于COREX流程.气基还原流程(MIDREX、HYL-Ⅲ、FINMET)目前都要使用天然气资源,很难在我国得到发展.转底炉可使用低强度的含碳球团,给煤基直接还原流程注入新的活力,但其能耗高、生产效率低、产品质量差将会制约它的发展.我国自主研发的炼铁新工艺,即低温快速还原工艺,目前仍处于研究开发阶段,它能够实现低温快速还原反应,是一种能耗低、污染少、资源利用率高的新型绿色冶金工艺流程,具有良好的发展前景.     

Estimation of Energy Consumption in COREX Process Using a Modified Rist Operating Diagram

Fuel consumption in the COREX-3000 process run in Baosteel is currently higher than the design index.Therefore,mass and heat balance equations for the COREX process were established using the basic principles included in the Rist operating diagram for blast furnace(BF)as a reference.Thermodynamic calculations were then used to modify the Rist operating diagram so that it was suitable for the COREX process.The modified Rist operating diagram was then applied for the evaluation of metallization rate(MR)and fuel structure to reduce the energy consumption in the COREX process.The modified Rist operating diagram for the shaft furnace(SF)provided a nearly ideal value for the restriction point W when the metallization rate was increased,while the point Pon the operating line for the melter gasifier(MG)moved upward due to reduction in the heat required in hearth.The feasibility of reducing the energy consumption during the COREX process by changing the fuel structure was also demonstrated.