两种脱硫灰的理化性质及其在湿法脱硫中的应用试验  

Physicochemical properties of two types of desulfurization ash and their application test in wet desulfurization

作　　者：张煜尧 黄亚继[1] 李志远 高嘉炜 刘俊 祁帅杰 赵佳琪 ZHANG Yuyao;HUANG Yaji;LI Zhiyuan;GAO Jiawei;LIU Jun;QI Shuaijie;ZHAO Jiaqi(School of Energy and Environment,Southeast University,Nanjing 211189,Jiangsu,China)

机构地区：[1]东南大学能源与环境学院,江苏南京211189

出　　处：《烧结球团》2024年第6期144-154,共11页Sintering and Pelletizing

基　　金：江苏省科技项目(BE2021701)。

摘　　要：为解决大型钢铁企业焦炉脱硫灰与半干法脱硫灰的处置难题,本文将两者掺混作为脱硫剂替代部分石灰石用于“石灰石-石膏”湿法脱硫工艺,通过粒度检测以及SEM、XRF、XRD、TG-DTG等表征方法分析脱硫灰的理化特性,并进行不同脱硫灰掺混比例下烟气温度、入口SO_(2)浓度、烟气流量、液气比和浆液pH值对脱硫效率的影响试验,探究最优脱硫石膏品质下脱硫灰的最佳掺混比例。结果表明:焦炉脱硫灰的粒度分布均匀,孔隙结构疏松,主要成分碳钠矾中Na_(2)SO_(4)和Na_(2)CO_(3)都对湿法脱硫起促进作用;两种脱硫灰掺混使用可以提高脱硫浆液的均匀性和流动性,解决半干法脱硫灰直接用于湿法脱硫存在的脱硫效率较低的问题;此外,脱硫效率随烟气温度、入口SO_(2)浓度、烟气流量的升高而降低,随液气比、pH的升高而升高。掺混适当比例的焦炉脱硫灰可以提升脱硫性能,尤其在低温、高SO_(2)浓度和烟气流速较快时脱硫性能提升效果突出。综合而言,当焦炉脱硫灰掺混比为5%时,脱硫剂的脱硫效果和产生的石膏品质最好,平均脱硫效率可达96%以上,脱硫石膏品质仍可满足国家三级石膏标准和国家土壤污染风险管控标准。In order to solve the disposal problem of coke oven desulfurization ash and semi-dry desulfurization ash in large iron and steel enterprises,the two are blended as desulfurizers to replace part of the limestone in the“limestone-gypsum”wet desulfurization process,and the physical and chemical properties of desulfurization ash are analyzed by particle size detection and SEM,XRF,XRD,TG-DTG and other characterization methods,and the effects of gas temperature,inlet SO_(2)concentration,gas flow,liquid-gas ratio and slurry pH value on desulfurization efficiency under different desulfurization ash blending ratios are tested in order to explore the optimal blending ratio of desulfurization ash under the optimal quality of desulfurization gypsum.The results show that the particle size distribution of coke oven desulfurization ash is uniform,the pore structure is loose,and the main components of sodium carbonate alum,Na_(2)SO_(4)and Na_(2)CO_(3),both play a promoting role in wet desulfurization.The blending of the two desulfurization ashes can improve the uniformity and fluidity of the desulfurization slurry,and solve the problem of low desulfurization efficiency of semi-dry desulfurization ash directly used in wet desulfurization.In addition,the desulfurization efficiency decreases with the increase of gas temperature,inlet SO_(2)concentration and gas flow,and increases with the increase of liquid-gas ratio and pH value.Blending an appropriate proportion of coke oven desulfurization ash can improve the desulfurization performance,especially at low temperature,high SO_(2)concentration and fast gas velocity.In general,when the blending ratio of desulfurization ash in coke oven is 5%,the desulfurization effect of the desulfurizer and the quality of the gypsum produced are the best,and the average desulfurization efficiency can reach more than 96%,and the quality of desulfurization gypsum can still meet the national third-level gypsum standard and the national soil pollution risk control standard.

关 键 词：脱硫灰 石灰石-石膏 湿法脱硫工艺 脱硫效率 

分 类 号：X757[环境科学与工程—环境工程] X701.3