烧结烟气脱硫石膏CO/H_(2)还原脱硫试验研究  

Experimental studies on reduction desulfurization of FGD gypsum from iron ore sintering process using CO/H_(2)

作　　者：左大文 巩磊[2] 韦杰 邓波 邵兴 杨世山[1] Zuo Dawen;Gong Lei;Wei Jie;Deng Bo;Shao Xing;Yang Shishan(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;Department of Energy and Environmental Protection,Ningbo Iron and Steel Co.,Ltd.,Ningbo 315807,Zhejiang,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]宁波钢铁有限公司能源环保部,浙江宁波315807

出　　处：《钢铁钒钛》2021年第1期83-92,共10页Iron Steel Vanadium Titanium

摘　　要：通过热力学软件Factsage7.3对CO/H_(2)还原CaSO_(4)进行热力学平衡计算。计算得到CO/H_(2)还原CaSO_(4)生成CaO和SO_(2)的最佳理论条件为:反应温度1 100℃以上、摩尔比n(CO)∶n(CaSO_(4))=n(H_(2))∶n(CaSO_(4))=1,过高或过低的还原剂摩尔比均不利于CaSO_(4)的还原脱硫,同时温度越高越有利于CaSO_(4)的CO/H_(2)还原脱硫。根据Factsage7.3计算结果,以N_(2)作为混合气体,在高温炉中进行了15 g烧结烟气脱硫石膏的CO/H_(2)还原脱硫试验,考察CO/H_(2)浓度、反应温度、反应时间、还原气体流量对脱硫石膏CO/H_(2)还原脱硫的影响。结果表明:有利于脱硫石膏CO还原脱硫的最佳条件为CO浓度5%、反应温度1 050℃、反应时间30 min、气体流量5 L/min;有利于脱硫石膏H_(2)还原脱硫的最佳条件为H_(2)浓度8%、反应温度1 050℃、反应时间30 min、气体流量为5 L/min,且CO分解还原脱硫效果较H_(2)还原脱硫的效果要好。试验发现在900℃以上时脱硫石膏有烧结现象发生,且随温度升高烧结程度更重,影响了CO/H_(2)的还原脱硫效率。The thermodynamic equilibrium of CO/H_(2) reduction of CaSO_(4) was calculated through software FactSage 7.3. The optimum theoretical conditions for generation of CaO and SO2 by CO/H_(2) reduction of CaSO_(4) were obtained at more than 1 100 ℃ of reaction temperature and mole ratio of n(CO)∶n(CaSO_(4))=1 or n(H_(2))∶n(CaSO_(4))=1. The reduction agent with a too high or too low mole ratio(n(CO)∶n(CaSO_(4)) or n(H_(2))∶n(CaSO_(4))) is not beneficial to the reduction desulfurization of CaSO_(4). A higher temperature is favorable for the CO/H_(2) reduction desulfurization of CaSO_(4). According to the thermodynamic calculation results, experimental studies on reduction desulfurization of FGD gypsum from iron ore sintering process were carried out using CO/H_(2)+N_(2) mixture gas in a furnace, and the influences of CO/H_(2) concentration, reaction temperature, reaction time and gas flow rate on the reduction desulfurization of FGD gypsum by CO/H_(2) were studied. The results show that the beneficial conditions for CO reduction desulfurization of FGD gypsum are CO concentration of 5%, temperature of 1 050 ℃ for 30 min and gas flow rate of 5 L/min. The beneficial conditions for H_(2) reduction desulfurization are H_(2) concentration of 8%, temperature of 1 050 ℃ for 30 min and gas flow rate of 5 L/min. The efficiency of reduction desulfurization by CO is better than that by H_(2). During the reduction process, FGD gypsum sinters above 900 ℃ and it makes a notable impact on the reduction desulfurization of the FGD gypsum.

关 键 词：烧结 烟气 脱硫石膏 还原脱硫 CO H_(2) 脱硫率 

分 类 号：X757[环境科学与工程—环境工程]