300 MW等级燃煤机组煤粉炉与循环流化床锅炉汞排放特性比较  

Comparison of mercury emission from around 300 MW coal-fired power generation units between pulverized boiler and circulating fluidized-bed boiler

作　　者：魏绍青 滕阳[2,3] 李晓航[3] 苏银皎 杨玮 张锴[2,3] 

机构地区：[1]晋能电力集团有限公司,山西太原030002 [2]山西省煤炭清洁燃烧发电工程技术研究中心(筹),山西太原030006 [3]华北电力大学热电生产过程污染物监测与控制北京市重点实验室,北京102206 [4]晋能长治热电有限公司,山西长治046011

出　　处：《燃料化学学报》2017年第8期1009-1016,共8页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金联合基金项目(U1610254);2015年度山西省科技重大专项(MD2015-01);中央高校基本科研业务费(2017MS020)资助~~

摘　　要：选取某地330 MW煤粉炉(PC炉)和350 MW循环流化床锅炉(CFB)的燃煤电厂进行汞排放特性的研究。采用30B法和安大略法对两个燃煤电厂的除尘器入口、除尘器出口、脱硫塔出口和湿式电除尘器出口的烟气进行了取样和汞浓度分析,采集了入炉煤和副产物底渣、飞灰及脱硫石膏样品。通过样品中汞含量的分布,探讨了PC炉与CFB锅炉机组现有污染物控制设备对汞的协同脱除作用。结果表明,350 MW CFB电厂除尘器出口烟气平均汞浓度降低至0.43μg/m^3,布袋除尘器对汞的捕获效率达到98.9%,相应的燃烧副产物中飞灰是汞的主要富集对象。对于330 MW PC炉电厂,除尘器入口和除尘器出口烟气汞浓度均高于350 MW CFB电厂,烟气汞浓度从除尘器入口、除尘器出口到脱硫塔出口依次降低,在脱硫塔出口烟气汞浓度降低至0.42μg/m^3,静电除尘器和湿式脱硫塔对烟气汞的捕获效率分别为75.0%和22.4%,相应的产物中飞灰和脱硫石膏中汞都有一定程度的富集。The mercury emission characteristics are investigated and compared at a coal-fired power plant with330 MW pulverized coal（ PC） boiler and a coal-fired power plant with 350 MW circulating fluidized bed（ CFB）boiler. EPA 30 B method and Ontario method were used to test the mercury concentration in flue gas at the inlet of dust extraction unit,outlet of dust extraction unit,outlet of desulfurization unit,and outlet of wet dust extraction unit. The feed coal,bottom ash,fly ash and gypsum sample were collected at the same time together with gas sampling. The effect of the existing air pollution control device on mercury control was discussed toward PC and CFB units based on the mercury distribution data. The results show that the mercury concentration at fabric filter（ FF） outlet of CFB power plant is decreased to 0.43 μg/m3 and the mercury removal efficiency of FF reaches 98.9%. A predominating portion of mercury is enriched in fly ash. With respect to a PC power plant,the mercury concentrations at inlet and outlet of ESP are both higher than those in the CFB power plant,and the mercury concentration gradually drops from electrostatic precipitator（ ESP） inlet to wet flue gas desulfurization（ WFGD） outlet. The mercury concentration reaches a low value of 0.42 μg/m3 at the WFGD outlet,and the mercury removal efficiency of ESP and WFGD is 75.0% and 22.4%,respectively,which can meet the ultra low mercury emission controlling.

关 键 词：燃煤电厂 汞排放 污染物监测 煤粉炉 循环流化床 

分 类 号：X511[环境科学与工程—环境工程]