热废气循环条件下的烧结过程反应解析  

Analysis on reaction in sintering process under hot exhaust gas circulation

作　　者：章裕东 龙红明 伍英[2] 周江虹[3] 凌海涛 王毅璠 张晓萍[3] Zhang Yudong;Long Hongming;Wu Ying;Zhou Jianghong;Ling Haitao;Wang Yifan;Zhang Xiaoping(School of Metallurgical Engineering,Anhui University of Technology,Ma'anshan 243032,Anhui;Iron-making Plant,Baoshan Iron&Steel Co.,Ltd.,Shanghai 200941;Ma'anshan Iron&Steel Co.,Ltd.,Ma'anshan 243000,Anhui)

机构地区：[1]安徽工业大学冶金工程学院,安徽马鞍山243032 [2]宝山钢铁股份有限公司,上海200941 [3]马鞍山钢铁股份有限公司,安徽马鞍山243000

出　　处：《烧结球团》2020年第5期63-70,共8页Sintering and Pelletizing

基　　金：国家自然科学基金资助面上项目(51674002);国家自然科学基金重点资助项目(U1660206)。

摘　　要：基于铁矿烧结过程中的物理化学反应,研究其传热与传质过程。通过建立模型对料层内气流平均速度、压力分布、料层温度以及烟气成分和体积分数进行模拟计算,分析热废气循环条件下的各烧结反应行为,并结合烧结现场工艺状况,对模型进行验证。结果表明:烟气中的CO2受焦粉燃烧和熔剂热分解影响,体积分数由最初的9.93%上升至13.10%,烟气中CO体积分数随着燃烧反应的进行略有增加。在靠近点火端的料层高温区域,料层中的水分开始蒸发,循环烟气中H2O体积分数为5.2%;烟气经过湿料,水分发生冷凝,料层中含水量由初始时刻的6.0%升高到10.5%,产生过湿现象。同时,对现场工艺进行测试,气体流速的波动范围在0.10~1.00 m/s之间时,烧结过程中O2、CO和CO2体积分数变化的模拟结果与现场测试结果相吻合。Based on the physical and chemical reactions in iron ore sintering,the heat transfer and the mass transfer are studied.Through simulating and calculating the average airflow velocity,pressure distribution,layer temperature,flue gas composition and volume fraction in the material layer,the sintering reaction behavior under the condition of heat exhausted gas circulation is analyzed,and the model is verified by combining with the on-site sintering process.The results show that the volume fraction of CO2 in flue gas increases from 9.93% to 13.10% under the influence of coke combustion and flux thermal decomposition,and the volume fraction of CO in flue gas increases slightly with the progress of combustion reaction.The moisture in the material layer near the high-temperature area of the material layer at the ignition end begins to evaporate,and the volume fraction of H2O in the circulating flue gas is 5.2%.After the flue gas passes through the wet material,the moisture condenses,and the moisture content in the material layer increases from 6.0% at the initial moment to 10.5%,resulting in over-wetting phenomenon.The volume fraction of H2O in the material layer drops to about 12.0%,which is consistent with the moisture content in the actual sinter layer.At the same time,the on-site process is tested,and the fluctuation range of gas velocity is 0.10~1.00 m/s.The simulation results of the changes of O2,CO and CO2 volume fraction in the sintering process are consistent with the on-site test results.

关 键 词：烧结 数学模型 热废气循环 C-O燃烧 

分 类 号：X701[环境科学与工程—环境工程]