烧结(球团)烟气典型环保工艺的SO3排放及NaHSO3喷射脱SO3技术的工程应用  

SO3 emission status from sintering(pellet) flue gas treated by typical environmentally friendly process and engineering application of NaHSO3 jet SO3 removal technology

作　　者：连风宝 LIAN Fengbao(Taiyuan Ecological Environment Monitoring Center of Shanxi Province,Taiyuan 030000,China)

机构地区：[1]山西省太原生态环境监测中心,太原030000

出　　处：《环境工程学报》2020年第6期1619-1628,共10页Chinese Journal of Environmental Engineering

基　　金：山西省科技重大专项(20181101016);山西省低碳联合基金资助项目(U1610101)。

摘　　要：SO3对人体及环境的危害均远大于SO2,为了较全面地表征烧结(球团)烟气SO3排放特征并研究其SO3控制技术,以实验研究为基础,对不同SO3测试方法进行了对比分析;采用PENTOL SO3分析仪,首次对5个典型的烧结(球团)工程实施SO3测试,研究其SO3排放特征及现有设备的SO3脱除规律。测试结果表明:烧结(球团)烟气SO3排放浓度为9.1~145.2 mg·m-3,高于燃煤电厂的SO3排放量,这主要与烧结(球团)工程原料、燃料含硫量有关;烟气治理工艺全流程的总SO3脱除效率为79.93%~93.75%,且循环流化床干法脱硫+袋式除尘器的工艺组合对SO3的脱除性能明显优于石灰石-石膏湿法脱硫。针对高SO3的烧结(球团)项目(723.6 mg·m-3)首次实施碱喷射脱SO3改造,工程实验表明,不同摩尔比(Na2:SO3)亚硫酸氢钠干粉喷射后,SO3排放浓度降幅显著,烟气治理工艺全流程的SO3总脱除效率从79.70%提高至96.31%~99.25%,电除尘器前后喷射(摩尔比(0.5+0.5)∶1)时SO3排放浓度最低,为5.3 mg·m-3;NOx、SO2和颗粒物排放均满足超低排放限值要求。研究结果可为后续烧结(球团)烟气的SO3排放控制提供参考。SO3 has much higher hazards to human body and environment than SO2. In order to comprehensively study the emission characteristics and control technology of SO3 from sintered(pellet) flue gas in China,different SO3 test methods were compared and analyzed based on experimental research. PENTOL SO3 analyzer was used to test SO3 concentration in 5 typical sintering(pellet) projects, and the SO3 emission characteristics and the SO3 removal rules by existing equipment were studied. The results showed that, SO3 emission concentration in sintered(pellet) flue gas was 9.1~145.2 mg·m-3 and higher than that of coal-fired power plants,which was mainly related to the sulfur contents in sintering(pellet) engineering materials and fuels. The total SO3 removal efficiency of the whole flue gas control process was 79.93%~93.75%, and the SO3 removal characteristic of the combination of circulating fluidized bed dry desulfurization-bag dust collector was obviously better than that of limeston-gypsum wet desulfurization. For high SO3 project(723.6 mg·m-3), alkali injection reformation for SO3 removal was made. The engineering experiments showed that, SO3 emission concentration declined significantly after NaHSO3 powder jet with different mole ratio(Na2: SO3), SO3 total removal efficiency of the whole flue gas control process increased from 79.70% to 96.31%~99.25%, of which the SO3 emission concentration was the lowest, 5.3 mg·m-3 when jet(mole ratio of(0.5 + 0.5):1) occurred before and after electric dust collector. NOx, SO2 and particulate matter emissions met the requirements of ultra-low emission limits. This study can provide reference for the SO3 emission control in the sintering(pellet) flue gas.

关 键 词：烧结(球团)烟气 SO3排放特征 SO3脱除效率 碱喷射脱SO3技术 SO3测试方法 

分 类 号：X505[环境科学与工程—环境工程]