氢气预还原冷却氧化球团新工艺有效能利用分析  

Exergy analysis of a novel process for oxidized pellets pre-reduction and cooling using hydrogen

作　　者：李峰 胡志敏[1,2,3] 储满生[1,2,3] 唐珏 田宏宇 LI Feng;HU Zhimin;CHU Mansheng;TANG Jue;TIAN Hongyu(School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China;Institute for Frontier Technologies of Low-Carbon Steelmaking,Northeastern University,Shenyang 110819,Liaoning,China;Engineering Research Center of Advanced Technology of Low Carbon Steel,Ministry of Education,Shenyang 110819,Liaoning,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110819 [2]东北大学低碳钢铁前沿技术研究院,辽宁沈阳110819 [3]低碳钢铁前沿技术教育部工程研究中心,辽宁沈阳110819

出　　处：《钢铁》2025年第2期33-42,共10页Iron and Steel

基　　金：国家自然科学基金资助项目(U23A20608,ZX20230376);国家资助博士后研究人员计划资助项目(GZC20230392);中央高校基本科研业务费资助项目(N2025023,N2225046);辽宁省科技计划联合计划资助项目(2023-BSBA-109);中国五矿集团有限公司科技专项计划资助项目(2021ZXA04)。

摘　　要：在“双碳”背景下,高温氧化球团的余热回收成为钢铁生产的一个节能潜力点。采用氢气将氧化球团进行预还原和冷却,可提高球团的质量,同时降低后续冶炼工序的能量需求。采用基于热力学第二定律的有效能分析方法,对氢气预还原冷却氧化球团新工艺能量利用进行定量评价,考察了冷却气中氢气含量、氧化球团温度对新工艺有效能利用效率的影响。在此基础上,采用氢气冷却预还原氧化球团开展了热态试验。研究结果表明,在氢气体积分数为100%、氧化球团温度为1000℃条件下,预还原球团金属化率最高可达到32%,入炉氢气需求量为866.53 m^(3)/t,氢气利用率、热量利用效率、普遍有效能利用率和目的有效能利用率分别为25.55%、25.46%、92.03%和22.11%;当冷却气中氢气体积分数由100%降至60%时,冷却气需求量减少315.77 m^(3),但普遍有效能利用率降低6.54%,炉顶煤气温度升高,氢气体积分数不宜低于70%;当氧化球团温度由950℃升至1150℃,氢气需求量增加140.95 m^(3);预还原球团金属化率由30.50%提高至38.51%,但氢气利用率降低,普遍有效能和目的有效能利用率降低;采用100%氢气(体积分数)对温度为1000℃、品位为67.79%的氧化球团进行预还原冷却,预还原球团的金属化率达到34.77%,抗压强度和转鼓指数分别为1902 N/个和98.21%,满足后续工艺的生产要求。Under the background of "double carbon", the recovery of waste heat from high temperature oxidized pellets becomes an energy saving potential point in steel production. Pre-reduction and cooling of oxidized pellets using H_(2) can not only improve the quality of pellets, but also reduce the energy demands of subsequent processes. The exergy analysis method is adopted to quantitatively evaluate the energy utilization of the new process. The effects of H_(2) content in the cooling gas and oxidized pellet temperature on the effective energy utilization efficiency of the new process were investigated. Based on this, experiments were conducted, and the following conclusions were obtained.Under the condition of 100% H_(2)(volume fraction)and 1 000 ℃ of oxidized pellets, the maximum metallization rate of pre-reduction pellets can reach 32%. The demand for H_(2) is 866. 53 m^(3)/t(oxidized pellets). The hydrogen utilization rate, energy efficiency, and general and objective exergy efficiency are 25. 55%, 25. 46%, 92. 03% and 22. 11%, respectively. When the volume fraction of H_(2) in the cooling gas decreases from 100% to 60%, the demand for cooling gas decreases 315. 77 m^(3), but the general exergy efficiency decreases by 6. 54%. As the temperature of the top gas increases, the proportion of hydrogen should not be lower than 70%. When the temperature of the oxidized pellets increases from 950 ℃ to 1 150 ℃, the demand for hydrogen increases by 140. 95 m^(3), and the metallization rate of the pre-reduced pellets increases from 30. 50% to 38. 51%. However, the utilization rate of hydrogen decreases, and the general and objective exergy efficiency decreases. Under the condition of 100% H_(2)(volume fraction)and 1 000 ℃ of oxidized pellets, the metallization rate of the pre-reduced pellets reaches 34. 77%, and the compressive strength and drum index are 1 902 N/pellet and 98. 21%, respectively, meeting the production requirements of subsequent processes.

关 键 词：氢气 氧化球团 冷却 预还原 有效能 双碳 余热 抗压强度 转鼓指数 

分 类 号：TF046.6[冶金工程—冶金物理化学]