摘要
针对现今农村家用生物质锅炉氮氧化物排放较高的问题,设计了沙漏型炉膛结构以及尿素喷淋脱氮系统,并通过搭建锅炉实验台进行燃烧实验。选用三种生物质成型燃料颗粒进行试验研究,通过测量其氮氧化物的排放浓度、烟气氧含量和炉膛燃烧温度,结合氮氧化物生成的机理,详细分析了喷淋尿素溶液的位置、所喷淋尿素溶液的质量分数和生物质燃料的种类对氮氧化物排放浓度的影响。结果表明:生物质燃料的氮氧化物主要由锅炉的二次燃烧区域产生,因此在二次燃烧区喷淋尿素溶液可以更好地脱除燃烧生成的氮氧化物;随着喷淋尿素溶液质量分数的升高,氮氧化物排放浓度呈现先降低后增高的趋势,当尿素溶液质量分数为9.96%时,锅炉氮氧化物排放浓度最低;不同生物质燃料燃烧时氮氧化物的生成量会随着燃料本身的氮元素含量变化而变化,但是计算其基准氧含量折算浓度时也要综合考虑烟气氧含量。
In order to make full use of the biomass resources such as straw and wood in rural areas,the hourglass furnace structure and urea spray denitrification system were designed to solve the problem of high nitrogen oxide emission in rural household biomass boilers,and the combustion experiments were carried out by building a boiler test bench.In this paper,three kinds of biomass briquette fuel were selected for experimental research.By measuring the emission concentration of nitrogen oxides,the oxygen content of flue gas,and burning temperature in the furnace,combined with the formation mechanism of nitrogen oxides,the influence of the position of spraying urea solution,the mass concentration of spraying urea solution,and the influence of biomass fuel types on the emission concentration of nitrogen oxides was analyzed in details.The results show that the nitrogen oxides of biomass fuel are mainly produced in the secondary combustion area of the boiler,so spraying urea solution in the secondary combustion area can remove more nitrogen oxides generated by combustion.With the increase of the mass fraction of urea solution,the nitrogen oxide emission concentration showed a trend of decrease at first and then increase.When the mass fraction of urea solution was 9.96%,the nitrogen oxide emission concentration of boiler was the lowest.When different biomass fuels burned,the yield of nitrogen oxides changed with the change of the content of N element in the fuel itself,but the value of flue gas oxygen content should also be taken into account when calculating the reference oxygen content conversion concentration.
作者
翟雨轩
张兴惠
张聪
李曌
张宏
ZHAI Yuxuan;ZHANG Xinghui;ZHANG Cong;LI Zhao;ZHANG Hong(College of Civil Engineering, Taiyuan University of Technology, Taiyuan 030024, China)
出处
《太原理工大学学报》
CAS
北大核心
2021年第6期887-893,共7页
Journal of Taiyuan University of Technology
基金
山西省重点研发计划项目(社会发展领域)(201803D31035)
山西省重点研发计划项目(201903D321043)。
关键词
生物质能
氮氧化物
锅炉脱氮
尿素
烟气氧含量
biomass energy
nitrogen oxides
boiler denitrification
urea
oxygen content of flue gas
