用于挥发性颗粒物连续测量的冲击式采样器设计

摘要

In order to realize the continuous compensation measurement of volatile particulate in the PM2�5 measuring instruments with filter,we designed a double-channel continuous sampling and measuring device for volatile particulate with the condensing device and cascade impactor,which was based on the volatile particles’ physical characteristics of evaporating by heating and condensing by cooling. According to the particle size of 10μm, 5μm and 2�5μm,we designed three levels sampler,include the diameter and number of the apertures and other relevant parameters of the sampler. The sample in the sampler is directly measured by Quartz Crystal Microbalance( QCM) ,and cleaned by heating. Combine with the double-channel,it can sample and measure the volatile particles continuously. This sampler not only can be used in the compensation measuring continuously of volatile particulate in the PM2�5 measuring instruments with filter,so that its measurements will be more accurate;but also can be used directly in measuring and analysing of volatile particles.%为了实现滤膜式PM2�5测量仪中挥发性颗粒物的连续补偿测量，根据挥发性颗粒物加热挥发、冷却凝结的物理特性，利用冷凝装置和串级冲击采样器原理，设计了双通道的挥发性颗粒物连续采样测量装置。按照采样粒径为10、5、2�5μm的颗粒物设计了3级冲击采样器，通过理论计算得到了采样器的孔径、孔数等相关参数；对采样器中采集的样品使用石英晶体微天平（ QCM）直接测量，并采用加热清洗的方式结合双通道的设计实现挥发性颗粒物的连续采样测量。该装置不但可以应用于目前滤膜式颗粒物监测仪中的挥发性颗粒物补偿测量，使测量结果更加准确可靠；也可直接应用于挥发性颗粒物的测量分析。