基于数值模拟的不同氢碳比气基直接还原竖炉操作策略  

Operation strategies of gas-based direct reduction shaft furnace with different hydrogen-to-carbon ratios based on numerical simulation

作　　者：刘征建[1,2] 卢绍锋 王耀祖 张建良 承强[1] LIU Zhengjian;LU Shaofeng;WANG Yaozu;ZHANG Jianliang;CHENG Qiang(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Advanced Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Intelligence Science and Technology,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]北京科技大学高等工程师学院,北京100083 [3]北京科技大学智能科学与技术学院,北京100083

出　　处：《钢铁》2023年第10期42-50,共9页Iron and Steel

基　　金：国家自然科学基金资助项目(52174291)。

摘　　要：为降低CO_(2)排放,缓解温室效应,中国提出了“碳中和”、“碳达峰”的双碳战略,钢铁工业虽然是全球工业化进程中的重要支柱,但也是CO_(2)排放的主要来源之一,传统冶炼过程主要依赖于高炉炼铁,使用焦炭、煤粉等还原铁氧化物,导致大量CO_(2)被释放到大气中。因此,为实现双碳战略,钢铁工业亟需开发低碳氢冶金技术。气基竖炉工艺因其自身特点,采用天然气或焦炉煤气等富氢气体作为原料气,通过重整反应生成的还原气来还原铁氧化物,不仅取代了传统的化石燃料,同时还产生无污染的水蒸气。因此,气基竖炉工艺作为一种低碳氢冶金技术,能够显著降低钢铁生产过程中的CO_(2)排放,在未来钢铁行业的绿色、低碳发展中具有巨大的潜力。建立了涉及还原反应和渗碳反应的气基竖炉二维CFD数值模拟模型,研究了还原气氢碳比、还原气温度以及炉顶压力等对气基竖炉的影响。结果表明,提高还原气氢碳比(体积分数比)和炉顶压力有利于降低炉内温度,抑制炉料黏结;氢碳比由1.75提高至100%H_(2)(体积分数),DRI金属化率由0.93降低至0.84,提高还原气温度、流量和炉顶压力均可以提高DRI金属化率;同时,提高还原气温度和炉顶压力还可以提高H_(2)利用率,但提高还原气流量会导致H_(2)利用率降低。In order to reduce carbon dioxide emissions and alleviate the greenhouse effect,China puts forward the strategic goals of"carbon neutrality"and"carbon peaking".The iron and steel industry,while being a crucial pillar of the global industrialization process,is also one of the major sources of CO_(2)emissions.The traditional process relies heavily on blast furnaces for iron production,which involves the use of coke,coal,and other reducing agents to convert iron oxides,resulting in the release of significant amounts of CO_(2)into the atmosphere.Therefore,in order to achieve a"double carbon"target,the steel industry urgently needs to develop low-carbon hydrogen metallurgy technologies.The gas-based shaft furnace process,due to its unique characteristics,utilizes hydrogen-rich gases such as natural gas or coke oven gas as feed gas.These gases undergo reforming reactions to generate a reducing gas,which is then used to reduce iron oxides.This process not only replaces traditional fossil fuels but also produces non-polluting water vapor.Thus,as a low-carbon hydrogen metallurgy technology,the gas-based shaft furnace process has enormous potential to significantly reduce CO_(2)emissions in the steel production process and play a crucial role in the future green and low-carbon development of the steel industry.A two-dimensional CFD model of the gas-based shaft furnace was established,and the effects of reducing gas hydrogen-to-carbon ratios,reducing gas temperature and top gas pressure on the gas-based shaft furnace were studied.The results show that increasing the hydrogen-to-carbon ratios(volume percent ratio)of reducing gas and top gas pressure is beneficial to reduce the furnace temperature and restrain the bonding of burden,the hydrogen-to-carbon ratios increases from 1.75 to 100%H_(2)(volume percent),the DRI metallization degree decreases from 0.93 to 0.84.Increasing the gas temperature,gas flow rate and top gas pressure can increase the metallization degree of DRI.At the same time,increasing the reducing gas tempera

关 键 词：炼铁 气基竖炉 数值模拟 氢碳比 氢冶金 

分 类 号：TF554[冶金工程—钢铁冶金]