污泥与煤在循环流化床混烧过程中的汞排放特性  

Characteristics of mercury emission during co-combustion of sludge and coal in a circulating fluidized bed

作　　者：吴成军[1] 段钰锋[1] 赵长遂[1] 王运军[1] 王乾[1] 杨立国[1] 江贻满[1] 

机构地区：[1]东南大学热能工程研究所,南京210096

出　　处：《环境科学学报》2008年第7期1347-1353,共7页Acta Scientiae Circumstantiae

基　　金：国家重点基础研究发展计划"973计划"(No.2006CB200300)~~

摘　　要：在密相床截面积为0.23m×0.23m、高度为7.00m的循环流化床燃烧试验装置上进行了含汞污泥与煤的混烧试验.测试并分析讨论了污泥与煤混烧过程中汞的分布,探讨了Ca/S摩尔比、脱硫剂种类、过量空气系数等运行参数以及烟气成分对汞在烟气、飞灰和炉渣中形态分布的影响规律.结果表明,大部分汞进入烟气,且元素汞是混烧烟气中的主要存在形态.钙基脱硫剂对烟气中氧化态汞有较强的吸附脱除作用,CaO对汞的脱除效果要好于CaCO3.随着烟气中SO2、NOx浓度的增大,烟气中二价汞所占份额呈上升趋势.过量空气系数对烟气和灰渣中汞的浓度和形态分布有较大的影响.An experimental study on co-combustion of sludge and coal was conducted in a circulating fluidized bed furnace having a dense bed cross section of 0.23 m×0.23 m and height of 7 m. The speciation distribution of emitted mercury was measured and is discussed. The effects of major operational parameters such as Ca/S molar ratio, desulfurization sorbents and excess air coefficient and flue gas components on the speciation distribution of mercury in flue gas, fly ash and slag during the co-combustion process were investigated. The results indicate that the majority of mercury goes into flue gas in which elemental mercury is the major species. Calcium-based sorbents can adsorb Hg^2＋ in flue gas effectively, and CaO can adsorb more mercury than CaCO3. The content of Hg^2＋ in flue gas increases with the concentrations of SO2 and NOx in flue gas. The excess air coefficient was found to greatly influence mercury concentration and its speciation both in flue gas and in fly ash and slag.

关 键 词：循环流化床 污泥 煤 混烧 汞 排放 

分 类 号：X703[环境科学与工程—环境工程] TK16[动力工程及工程热物理—热能工程]