不同温度生物质气与煤粉混燃过程及污染物排放特性  

Study on co-combustion process and pollutant emission characteristics of biomass gas and pulverized coal at different temperatures

作　　者：张小桃[1] 赵伟[1] 闻猛 

机构地区：[1]华北水利水电大学电力学院,河南郑州450011

出　　处：《热力发电》2017年第9期47-52,共6页Thermal Power Generation

基　　金：河南省教育厅自然科学研究计划项目(2011A140014);河南省科技发展计划项目(112102210281)~~

摘　　要：为了研究不同温度生物质气与煤粉混燃对锅炉燃烧过程的影响,基于Fluent软件,搭建生物质气和煤粉混燃模型,对某电厂亚临界300 MW机组锅炉分别进行了纯煤粉燃烧和掺烧10%的300℃、450℃和600℃生物质气4种工况的炉内燃烧数值模拟,分析不同工况下炉内速度场、温度场、组分场以及污染物NO_x分布特征。结果表明:与纯煤粉燃烧相比,生物质气掺烧后,底层燃烧器生物质气出口烟气速度增加,炉膛中心燃烧温度降低,炉膛出口O_2和CO体积分数升高,而CO_2和NO体积分数降低;随着生物质气温度的升高,相对于纯煤粉工况,其他3种掺烧工况NO_x质量浓度分别降低了15%、24%、32%。In order to investigate the influence of temperature on combustion process of biomass gas mixed with pulverized coal, the co-firing models were built using the Fluent software. By taking a subcritical 300 MW unit boiler as the object, the combustion processes under different conditions were simulated, the velocity field, temperature field, flue gas components and the NOx distribution features in the furnace were numerically analyzed. The four conditions were pure pulverized coal combustion case and three co-firing cases with 10% biomass gas at 300 ~C, 450 ~C and 600 ~C. The results show that, compared with pure coal combustion condition, during the co- combustion process, the outlet biomass gas velocity at lower burner increases, the temperature at the furnace center decreases, the 02 and CO volume fraction at furnace outlet increases while the CO2 and NO decreases. The mass concentration of NOx decreases by 15%, 24% and 32% with the increasing biomass gas temperature.

关 键 词：生物质气 煤粉 混合燃烧 速度场 温度场 组分场 NOX排放 数值模拟 

分 类 号：TK16[动力工程及工程热物理—热能工程]