摘要
近年来,国家对于环境保护的要求愈发严苛,煤电行业节能减排任务愈加艰巨,燃煤电厂的超低排放改造工作迫在眉睫。笔者针对3台220t/h煤粉锅炉NOx进行臭氧脱硝改造和脱硝试验研究,采用烟气分析仪及电厂在线检测系统,探究了O3/NO摩尔比及NOx初始浓度等对脱硝效果的影响。试验结果表明,活性分子臭氧脱硝技术对该煤粉炉锅炉具有较好的脱硝效果,NOx脱除效率可达90%以上。锅炉出口NOx浓度随锅炉负荷波动较大,呈正相关关系,锅炉负荷升高,出口NOx浓度升高;锅炉负荷降低,出口NOx浓度随之降低。臭氧脱硝效率随O3/NO摩尔比和臭氧投加量的增加而增大,但当O3/NO摩尔比超过一定值后,其增大速率随臭氧量的增加而逐渐变缓。臭氧脱硝技术中脱硝效率受NOx初始浓度的影响较小,O3/NO摩尔比达到一定量时,可保证不同NOx初始浓度波动下的脱硝效率。本试验获得的特性曲线为臭氧脱硝技术最佳臭氧喷射量的确定提供了依据,即在保证脱硝效率的前提下,如何选择最佳的O3/NO摩尔比。应用臭氧脱硝技术后,该电厂顺利通过了168h测试,烟气排放中NOx浓度稳定在50mg/Nm3以下,满足国家超低排放要求,可见采用活性分子臭氧对烟气中的NOx具有良好的脱除效果。
In recent years,the requirement of environmental protection has become more and more stringent,and the task of energy saving and emission reduction in coal-fired power industry has become more and more arduous.The transformation of ultra-low emission of coal-fired power plants is imminent.In this paper,three 220 t/h pulverized coal fired boilers were revamped with ozone denitration technology,and a series of debugging tests were carried out.With the help of flue gas analyzer and on-line detection system of power plant,the effects of O3/NO molar ratio and initial concentration of NOx on denitration effect were mainly explored.The experimental results show that the application of ozone denitration technology in the pulverized coal boiler has a very good denitration effect,and the removal efficiency of NOx reaches more than 90%.The NOx concentration at the outlet of the boiler fluctuates greatly with the boiler load.The boiler load increases and the NOx concentration at the outlet increases.If the boiler load decreases,the NOx concentration at the outlet also decreases,showing a positive correlation.The efficiency of ozone denitration increases with the increase of the molar ratio of O3/NO and ozone dosage,but when the molar ratio of O3/NO exceeds a certain value,the rate of ozone denitration increases slowly with the increase of ozone dosage.In ozone denitration technology,the denitration efficiency is less affected by the initial concentration of NOx .When the molar ratio of O3/NO reaches a certain value,the denitration efficiency can be guaranteed under different conditions of the initial concentration fluctuation of NOx .The characteristic curve obtained in this experiment provides a basis for determining the optimum ozone injection quantity in the application of ozone denitration technology,that is,how to select the optimum O3/NO ratio on the premise of ensuring the denitration efficiency.After the application of ozone denitration technology,the power plant passed 168 hours of test successfully.The concentratio
作者
张利波
刘佩希
张椰
徐超群
邵嘉铭
何勇
王智化
ZHANG Libo;LIU Peixi;ZHANG Ye;XU Chaoqun;SHAO Jiaming;HE Yong;WANG Zhihua(China Huadian Power Group Harbin Power Generation Co.,Ltd.,Harbin 150040,China;State Key Laboratory of Clean Energy Utilization,Zhejiang University,Hangzhou 310027,China;Jilin Zheda Energy Clean Utilization Technology Co.,Ltd.,Jilin 130213,China)
出处
《洁净煤技术》
CAS
2019年第3期105-109,共5页
Clean Coal Technology
基金
浙江省自然科学基金杰出青年基金资助项目(LR16E060001)
关键词
煤粉炉
臭氧
脱硝
NOx
超低排放
coal fired boiler
ozone
denitration
NOx concentration
ultra-low emission
