烧结SDA脱硫灰还原煅烧解析SO2过程分析  

Process analysis of SO2 released by reduction calcination experiment of sintering semi-dry desulfurization ash

作　　者：茅沈栋 苏航 王飞 毛瑞 MAO Shen-dong;SU Hang;WANG Fei;MAO Rui(Institute of Research of Iron and Steel,Shasteel,Suzhou 215000,Jiangsu,China)

机构地区：[1]江苏省(沙钢)钢铁研究院,江苏苏州215000

出　　处：《钢铁研究学报》2020年第7期610-617,共8页Journal of Iron and Steel Research

摘　　要：烧结半干法(SDA)脱硫灰是钢铁企业烧结烟气脱硫副产物,因其成分复杂,组分含量波动大且含有未反应完全的氢氧化钙,一直没有较好的利用方式,目前的研究多以氧化改性为主。提出了一种处理半干法脱硫灰的新途径,将脱硫灰中的S以SO2形式解析出用于制酸,反应后固体产物也可二次利用。开展了脱硫灰还原煅烧模拟试验。结果表明,脱硫灰是一种高钙高硫产物,主要物相为CaSO3·0.5H2O、Ca(OH)2、CaCO3和KCl,90%颗粒的粒径小于77μm。在N2氛围下,煅烧温度从950℃升高至1100℃,亚硫酸钙和脱硫灰的失重与脱硫率也随之升高。在CO与CO2混合气体氛围下,随着煅烧温度从900升高至950℃以及CO体积分数从10%增至50%,亚硫酸钙的失重从26.2%上升至57.5%,脱硫率从41.9%下降至37.9%;脱硫灰的失重从23.0%上升至40.5%,脱硫率从33.9%下降至8.3%。随着CO体积分数增加,CaS的生成量增加,以SO2形态离开反应体系的S相应降低,从而使得脱硫率下降。The sintering semi-dry desulfurization ash is a byproduct of sintering flue gas desulfurization in iron and steel industries,it has not been well utilized due to its complex composition,large fluctuation of components and unreacted calcium hydroxide.At present,most of the studies focused on oxidation modification.A new way of disposing semi-dry desulfurization ash was proposed,the sulfur in the desulfurization ash could be released in the form of SO2 which could be used for producing sulfuric acid,the solid product after reaction could also be reused.Then reduction calcination simulative experiment was carried out.The results show that semi-dry desulfurization ash is a kind of product with high content of Ca and S,the main phases are CaSO3·0.5H2O,Ca(OH)2,CaCO3 and KCl,the size of 90% particle is less than 77μm.In N2 atmosphere,when calcination temperature rises up,the weight loss and desulfurization rate of calcium sulfite and semi-dry desulfurization ash also rise up.In atmosphere of CO and CO2 mixture,when calcination temperature rises from 900to 950℃ and volume fraction of CO rises from 10% to 50%,the weight loss of calcium sulfite rises from 26.2% to 57.5% and the desulfurization rate falls from 41.9% to 37.9%;the weight loss of semi-dry desulfurization ash rises from 23.0% to 40.5% and the desulfurization rate falls from 33.9% to 8.3%.As the volume fraction of CO increases,the production of CaS increases,the sulfur leaving the reaction system in the form of SO2 decreases accordingly,so that the desulfurization rate reduces.

关 键 词：半干法脱硫灰 还原煅烧 亚硫酸钙 脱硫率 

分 类 号：X757[环境科学与工程—环境工程]