燃煤电站锅炉脱硝精准喷氨技术研究及应用  

Technology Study and Application of Precise Ammonia Injection for Denitrification Systems of Coal-Fired Power Generation Plants

作　　者：周国民[1] 付鹏 王富强 周星龙 乔加飞 郝卫 韩斌桥 ZHOU Guomin;FU Peng;WANG Fuqiang;ZHOU Xinglong;QIAO Jiafei;HAO Wei;HAN Binqiao(China Shenhua Energy Co., Ltd., Guohua Power Branch, Beijing 100025, China;Shenhua Guohua(Beijing)Electric Power Research Institute Co.,Ltd.,Beijing 100024,China)

机构地区：[1]中国神华能源股份有限公司国华电力分公司,北京100025 [2]神华国华(北京)电力研究院有限公司,北京100024

出　　处：《锅炉技术》2020年第6期73-79,共7页Boiler Technology

摘　　要：针对燃煤电站锅炉脱硝系统出现的喷氨量不均、氨逃逸增加、易造成空气预热器堵塞等问题,通过数值模拟提出流场优化改造方案,在SCR系统烟道内加装圆形混合器,对喷氨管路进行分区改造,实施喷氨总量控制和格栅均衡控制。脱硝精准喷氨改造后,机组NOx排放稳定控制在20 mg/Nm3,首层催化剂前截面氨氮摩尔比偏差从改造前的11%降低到5%以下,氨逃逸从7.8×10^-6降低到2×10^-6,尿素单耗从0.61 g/(kW·h)降低为0.56 g/(kW·h),稳态偏差值等各项指标皆优于验收标准,空气预热器差压得到有效控制。To solve the uneven spray amount of ammonia,excess amount of escaped ammonia and air preheater clogging,several technologies are studied in this paper.The optimize retrofit scheme is presented through the numerical simulation of flow field,and several circle mixers are added into the SCR flue system.Then ammonia injection pipes are modified into several parts,to control the total amount of ammonia and grille balance control.After denitration precision spraying ammonia reform,NOx emission is controlled around 20 mg/Nm3,NH3/NOx CV of first layer catalyst remarkably reduced from a high range(11%)to a rather low level(below 5%)and ammonia escape amount decreased from 7.8 ppm to 2 ppm,and urea consumption decreased from 0.61 g/(kW·h)to 0.56 g/(kW·h).The indicators are better than the acceptance criteria,and differential pressure of air preheater is effectively controlled.

关 键 词：燃煤锅炉 脱硝优化 精准喷氨 数值模拟 自动化 

分 类 号：X773[环境科学与工程—环境工程]