燃煤电厂湿法脱硫对细颗粒物的脱除特性  

Removal Characteristics of Fine Particles from Coal-Fired Power Plants by Wet Flue Gas Desulphurization

作　　者：续鹏[1,2] 薛志钢[2] 杨巨生[1] 杜谨宏[2] 马京华[2] 刘妍[2] 吴华成 

机构地区：[1]太原理工大学电气与动力工程学院,山西太原030024 [2]中国环境科学研究院,北京100012 [3]国网冀北电力科学研究院,北京100045

出　　处：《环境科学研究》2017年第5期784-791,共8页Research of Environmental Sciences

基　　金：国家电网公司科技项目(52010115002P);国家环境保护公益性行业科研专项(201509010)

摘　　要：应用DGI承重撞击器对四台燃煤机组湿法脱硫前、后细颗粒物进行采集,分析细颗粒物的粒径分布、元素组成以及脱硫系统的脱除效率.结果表明:脱硫前细颗粒物粒径峰值出现在0.20~0.40μm处,脱硫后峰值出现在0.20~0.30μm处.经过湿法脱硫系统后ρ(PM_(2.5))、ρ(PM_1)、ρ(PM_(0.5))、ρ(PM_(0.2))出现不同程度的增长,平均增长率分别为13.28%、19.57%、28.79%、33.51%.分粒径颗粒物中ρ(Si)、ρ(Al)在脱硫前、后均随着颗粒物粒径的减小呈递减趋势,并且脱硫后ρ(Si)、ρ(Al)均有不同程度的降低,ρ(Fe)随颗粒物粒径的减小呈增加趋势,表现出一定的富集特性;湿法脱硫后Ca在PM_1中的质量浓度出现明显的增长,ρ(Ca)由18.86~51.47μg/m^3增至41.87~84.83μg/m^3.Si、Al是PM_(2.5)中的主要元素,经过湿法脱硫后ρ(Si)、ρ(Al)由59%~72%降至43%~59%;而Ca在PM_(2.5)中表现出相反的变化趋势,ρ(Ca)由8%~13%升至17%~26%.Size-segregated fine particulate matters were sampled by Dekati Gravimetric Impacter （DGI） before and after wet flue gas desulfurization （WFGD） in four coal-fired units. The variations of mass concentration, size distribution and elemental composition of the fine particulate matters were analyzed. The results showed that peak values of fine particulate matters concentration was in the range of 0.20-0.40 μm before WFGD among the four units, while they decreased slightly to 0.20-0.30 μm after WFGD. After the process of wet desulfurization, the mass concentrations of PM2.5, PM1, PM0.5 and PM0.2 increased by 13.28%, 19.57%, 28.79% and 33.51%, respectively. The mass concentration of Si and Al reduced with the decrease of the particle size both before and after desulfurization, while Fe showed the opposite tendency, indicating its enriching property. After WFGD, the mass concentration of Si and Al decreased to varying degrees, while the mass concentration of Ca increased significantly from 18.86-51.47 μg/m3 to 41.87-84.83 μg/m3. After WFGD, the fraction of Si and Al, as the main elements in PM2.5, decreased from 59%-72% to 43%-59%, while Ca in PM2.5 showed the opposite trend, increasing from 8%-13% to 17%-26%.

关 键 词：燃煤锅炉 PM2.5 粒径分布 元素 

分 类 号：X513[环境科学与工程—环境工程]