摘要
燃煤锅炉生成的碳烟不仅会增强火焰辐射、影响燃烧外,还排放到大气环境中带来严重危害。为了进一步了解其生成机理从而更好地对其生成量及特性进行控制,对煤粉燃烧过程中颗粒周围碳烟的分布规律进行定量的研究十分必要。本文自行设计了注射式微量给粉装置,成功实现了0.1 g/h量级给粉率下的连续给粉,并通过改进多元扩散燃烧器和以及结合激光诱导白炽光(Laser Induced Incandescence)技术,首次实现了对单颗粒煤粉燃烧过程中碳烟分布的定量测量,发现对于70μm左右的煤粉颗粒,碳烟分布直径约为1 mm。此外还通过控制气氛,研究了含氧量对碳烟生成的影响,发现随着氧含量的上升,碳烟总浓度下降并且峰值出现更早的规律。
The soot,formed in pulverized coal boiler,not only affects the radiation and combustion status,but also emits to atmosphere causing noxious black carbons.However,the forming and distribution of soot cloud around a single coal particle is not well understood,which limits its further control during combustion.In this paper,a micro-scale injection feeder is successfully designed to achieve a feeding rate of 0.1 g/h,which is then connected to a Hencken-type multi-element diffusion flame burner for single particle combustion at centerline.The Laser Induced Incandescence is developed to measure soot distribution around coal particle.It is found that the radius of soot cloud is about 1 mm,which is about 14 times of the radius of coal particle itself.With increasing oxygen fraction,the averaged soot concentration decreases,which the peak of soot occurs much earlier.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2013年第1期185-188,共4页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.51176094)
关键词
煤粉
碳烟生成
激光诱导白炽光
注射式给粉器
pulverized coal
soot formation
laser induced incandescence
syringe feeder
