燃煤电厂烟尘排放是造成环境污染最主要的因素之一,实现电厂排放烟尘浓度的在线监测显得尤为重要。以光全散射法为理论基础,运用MATLAB编程,得到消光系数与粒径、复折射率的关系以及颗粒浓度与消光曲线的关系;在实验室搭建粉尘浓度监测台架,用0.81和2.1μm这2种聚苯乙烯标准颗粒在液相介质中对台架测试结果进行标定;而后选取3种粒径分布不同的二氧化硅球形颗粒进行测量,测量结果表明,样品中无量纲尺寸因子α〉30的颗粒所占的比例越高,浓度测量的误差越大。
Particulate matter(PM) emission of coal-fired power plant is one of the main factors that cause environmental pollution, So on-line monitoring of the PM concentration is of great importance.A MATLAB program was developed based on light scattering theory to study the relationship between the extinction coefficient and the size and complex refractive index of the particle. Moreover, the relationship between the particle concentration and the extinction curve was also studied. Then a self-designed particle concentration measuring device was built in the laboratory and calibrated with two standard particle samples. Three spherical silicon dioxide with different size distributions were used to investigate the impact of particle size distribution on the concentration measurement. The results show that the measurement deviation is increases with the fraction of particle with the dimensionless size factor α30 in the sample.