对冲燃烧锅炉掺烧污泥炉内燃烧及碱金属分布模拟研究  

Numerical simulation on co-combustion and alkali metal distribution in an opposed firing boiler mixed with sludge

作　　者：童家麟 张岩 刘文胜 茅建波 叶学民[2] TONG Jialin;ZHANG Yan;LIU Wensheng;MAO Jianbo;YE Xuemin(Hangzhou E-Energy Technology Company Limited,Hangzhou,310014,China;School of Energy Power and Mechanical Engineering,North China Electric Power University,Baoding 071003,China)

机构地区：[1]杭州意能电力技术有限公司,杭州310014 [2]华北电力大学动力工程系,河北保定071003

出　　处：《综合智慧能源》2024年第8期50-58,共9页Integrated Intelligent Energy

基　　金：河北省自然科学基金项目(A2015502058);杭州意能电力技术有限公司科技项目(EERD2021-03)。

摘　　要：以某660 MW对冲燃煤锅炉为对象,采用数值模拟方法研究了掺烧干化污泥时炉内燃烧及碱金属分布情况,分析了掺烧位置、过量空气系数和污泥Cl含量对炉内燃烧及碱金属组分分布的影响。结果表明:掺烧污泥后,侧墙壁面区域碱金属质量浓度较高,采用中上层燃烧器层掺烧污泥可降低碱金属的排放速率和燃尽风燃烧器附近区域金属壁温;提高过量空气系数不仅可提高煤粉燃尽率,还可以降低侧墙贴壁区域碱金属质量浓度;降低污泥中Cl含量可有效降低烟气中的碱金属质量浓度和其他碱金属向NaCl的转化率。实际锅炉掺烧干化污泥时,建议采用中上层燃烧器掺烧,并适当降低过量空气系数以降低掺烧对炉内受热面的沾污、结渣和碱金属型高温腐蚀风险。Taking a 660 MW opposed firing boiler as the study object,the combustion features and distribution of alkali metals in the furnace during co-combustion with dehydrated sludge are studied by numerical simulation,and the influence factors including the blending layer,excess air coefficient and different Cl content in sludge are analyzed.The cocombustion with dehydrated sludge will increase the alkali metal mass concentration on the furnace side wall.The study indicates that blending sludge on the middle and upper layer of the burner can reduce the emission rate of alkali metals and lower the wall temperature near OFA nozzles.Increasing excess air coefficient can improve the burnout rate of pulverized coal and reduce the alkali metal mass concentration on the side wall.And decline of the Cl content in sludge can effectively reduce the concentration of alkali metals in flue gas and conversion rate of alkali metal compounds to NaCl.Blending sludges on the middle and upper layers of a co-combustion burner can reduce the excess air coefficient and alleviate the fouling,slagging and alkali metal high temperature corrosion in the furnace.

关 键 词：电站锅炉 污泥掺烧 炉内燃烧 碱金属 数值模拟 

分 类 号：TK227.1[动力工程及工程热物理—动力机械及工程]