光散射法与β射线衰减-光散射联用法颗粒物在线测量方法对比

为考察光散射法和β射线衰减-光散射联用法的适用性，以β射线衰减法颗粒物自动监测仪（BAM）为标准，于2016年2月4日-4月18日，在中国环境科学研究院利用β射线衰减-光散射联用法颗粒物自动监测仪（MP-CPM）与光散射法传感器对ρ（PM₁₀）和ρ（PM_2.5）测量结果进行了对比.结果表明:① MP-CPM与BAM测量ρ（PM₁₀）的结果具有较好的一致性，相关系数为0.92，平均相对偏差为0.04%；ρ（PM_2.5）结果一致性较差，相关系数为0.69，MP-CPM测量ρ（PM_2.5）整体较高于BAM，平均相对偏差为45.8%.② 光散射法传感器与BAM测量ρ（PM_2.5）结果一致性较好，相关系数为0.85，平均相对偏差为11.24%，但ρ（PM₁₀）远低于BAM，平均相对偏差为-44.64%.在特殊污染情景下，光散射法将因受到较大影响而严重错估颗粒物浓度.烟花燃放期间，MP-CPM和光散射法传感器严重低估颗粒物浓度，与BAM测量颗粒物浓度的平均相对偏差均低于-50%；沙尘污染过程中，MP-CPM严重高估ρ（PM_2.5），与BAM测量ρ（PM_2.5）结果平均相对偏差为79.27%，光散射法传感器严重低估ρ（PM₁₀），与BAM测量ρ（PM₁₀）结果平均相对偏差为-59.35%.研究显示，不同原理的仪器，在不同的使用场景下应该区别对待. 

Inter-Comparison between Light Scattering and Beta-Attenuation-Light Scattering Particulate Matter On-Line Monitoring

In order to investigate the performance methods of light scattering and beta-attenuation-light scattering, inter-comparison between light scattering and beta-attenuation-light scattering combined method of particulate matter on-line monitoring equipment for PM₁₀ and PM_2.5 based on beta-attenuation method(BAM) was conducted from February 2016 to April 2016 at the Chinese Research Academy of Environmental Sciences.The results showed that PM₁₀ concentrations measured by MP-CPM were greatly correlated with BAM, with the correlation coefficient of 0.92 and average deviation 0.04%, much better than the results of PM_2.5, for which the correlation coefficient was 0.69 and the average deviation was 45.8%.PM_2.5 measured by light scattering sensor was closely correlated with BAM, with correlation coefficient 0.85 and average deviation 11.24%, but PM₁₀ was far lower than the BAM results, with average deviation-44.64%.In some special pollution episodes, the result of light scattering misestimated the real value of ambient PM.During fireworks, MP-CPM and light scattering sensor underestimated the particulate mass concentration, the relative deviation of both to BAM was less than 50%.During dust pollution, PM_2.5 measured by MP-CPM was overestimated, with average deviation between MP-CPM and BAM 79.27%, while PM₁₀ measured by light scattering sensor was underestimated, with average deviation between light scattering sensor and BAM -59.35%.The research shows that different principles of instrument should be treated differently under the different usage scenarios.The study provides scientific reference for the methods of light scattering and beta-attenuation-light scattering.