超临界CFB锅炉脱硝系统深度调峰改造研究  

Research on deep peak shaving transformation of denitration system of supercritical CFB boiler

作　　者：李鹏 LI Peng(Jiangsu Province Energy Investment Co.,Ltd.,Xuzhou 221018,China)

机构地区：[1]江苏省能源投资有限公司,江苏徐州221018

出　　处：《煤炭科技》2023年第6期35-39,44,共6页Coal Science & Technology Magazine

摘　　要：对超临界流化床锅炉低负荷时NO_(x)超标原因进行了分析,发现反应区温度下降是导致效率降低的主要原因。改用液氨或氨水作为脱硝还原剂,仅能将脱硝效率提高5%,效果并不理想;低负荷时炉膛内温度降低,仅比分离器入口处温度高10℃左右,在二次风口或点火油枪口加装尿素喷枪,未能获得较高的脱硝效率。经过分析比较,可行的改造方案是:在两级省煤器间加装SCR系统,或采用烟气再循环将低温烟气引入一次风系统。加装SCR系统需要做好催化剂的防堵塞、防磨损措施,烟气再循环投用要尽量避免锅炉效率降低太多。In this paper,the causes of NO_(x) exceeding the standard at low load of supercritical fluidized bed boiler were analyzed.It was found that the temperature drop in the reaction zone was the main reason for the reduction of efficiency.Using liquid ammonia or ammonia water as denitration reducing agent can only increase denitration efficiency by 5%,and the effect is not ideal.At low load,the temperature in the furnace decreases and is only about 10℃higher than the inlet of the separator.Adding a urea spray gun at the secondary air outlet or the ignition oil gun outlet can not obtain a high denitration efficiency.After analysis and comparison,the feasible transformation scheme is to install SCR system in the two-stage economizers,or use flue gas recirculation to introduce the low-temperature flue gas into the primary air system.The installation of SCR system needs to take anti blocking and anti-wear measures for catalyst,and the operation of flue gas recirculation should try to avoid too much reduction of boiler efficiency.

关 键 词：循环流化床 深度调峰 SCR 烟气再循环 

分 类 号：TM621[电气工程—电力系统及自动化]