垃圾焚烧锅炉二次风风速对NO_(x)污染控制及热效率影响的研究  

Study on the Influence of Secondary Air Velocity on NO_(x)Pollution Control and Thermal Efficiency of Waste Incineration Boiler

作　　者：郑闽锋 孙加康 龚凌诸 卢翔涛 朱猛 石祥 陈佳伟 ZHENG Minfeng;SUN Jiakang;GONG Lingzhu;LU Xiangtao;ZHU Meng;SHI Xiang;CHEN Jiawei(College of Eco-Environment and Urban Construction,Fujian University of Technology,Fuzhou 350118,China;Fujian Key Laboratory of Energy Measurement,Fujian Metrology Institute,Fuzhou 350110,China)

机构地区：[1]福建工程学院生态环境与城市建设学院,福建福州350118 [2]福建省计量科学研究院福建省能源计量重点实验室,福建福州350110

出　　处：《锅炉技术》2023年第5期8-16,共9页Boiler Technology

基　　金：福建省科技计划项目(2020Y0055);福州市科技计划项目(2021-P-046);福建省能源计量重点实验室开放课题(NYJL-KFKT-2021-02)。

摘　　要：为研究不同二次风风速对锅炉炉膛内温度、NO_(x)浓度、烟气停留时间分布及热效率的影响,针对某600 t/d城市生活垃圾焚烧锅炉的燃烧过程进行了数值模拟。结果表明:当后墙二次风风速在42~66 m/s、前墙二次风风速不变时,随着后墙二次风风速增大,第一烟道出口处NO_(x)浓度先升高后降低;当第一烟道出口处O_(2)含量从6.47%增加到7.02%,NO_(x)质量浓度从106.98 mg/m^(3)降低到100.18 mg/m^(3),降低了6.36%;前墙二次风风速为42 m/s,后墙二次风风速为66 m/s时,焚烧炉内温度梯度相较其他工况更加均匀,烟气在焚烧炉内温度大于1123 K区域停留时间超过2 s,有利于抑制二口恶英的生成;前墙二次风风速为45 m/s,后墙二次风风速为70 m/s时,相较原始工况第一烟道出口处平均温度降低19.51 K,排烟热损失降低0.83%,固体未完全燃烧热损失降低0.16%,焚烧炉热效率提高0.99%。该研究对垃圾焚烧锅炉低污染、高效率运行具有重要的指导意义。In order to study the effects of different secondary air velocity on temperature,NO_(x)concentration,flue gas residence time distribution and thermal efficiency in boiler furnace,a numerical simulation was carried out for the combustion process of a 600 t/d municipal solid waste incineration boiler.The results show that when the secondary air velocity of the rear wall is between 42 and 66 m/s and the secondary air velocity of the front wall remains unchanged,as the secondary air velocity on the back wall increases,the NO_(x)concentration at the outlet of the first flue gas duct increases first and then decreases.When the O_(2) content at the outlet of the first flue gas duct increases from 6.47%to 7.02%,the NO_(x)concentration decreases from 106.98 mg/m^(3)to 100.18 mg/m^(3)by 6.36%.When the front wall secondary air velocity is 42 m/s,and the rear wall secondary air velocity is 66 m/s,the temperature gradient in the incinerator is more uniform than that in other conditions,and the residence time of flue gas in the incinerator is more than 2 s in the area where the temperature is greater than 1123 K,which is beneficial to inhibit the formation of dioxin.When the air velocity of the front wall secondary air is 45 m/s and the air velocity of the rear wall secondary air is 70 m/s,the average temperature at the outlet of the first flue gas duct is 19.51 K lower than the original condition,the smoke exhaust heat loss is 0.83%lower,the heat loss of incomplete combustion of solid is 0.16%lower,and the thermal efficiency of the incinerator is increased by 0.99%.This study has important guiding significance for the low pollution and high efficiency operation of the waste incineration boiler.

关 键 词：城市生活垃圾 数值模拟 二次风风速 NO_(x)浓度 热效率 

分 类 号：TK227.1[动力工程及工程热物理—动力机械及工程]