民用散煤燃烧排放颗粒物微观特征

为深入了解民用散煤燃烧排放颗粒物对大气环境的影响，利用自行设计的采样装置采集民用散煤燃烧颗粒物并采用扫描电镜-能谱（SEM-EDX）分析颗粒物的形貌和元素组成。结果表明，民用散煤燃烧排放的颗粒物主要有焦油球，飞灰，片状或块状碳质颗粒，矿质颗粒，烟尘集合体，其他颗粒。从形貌上看，民用散煤燃烧排放颗粒物以球形和类球形颗粒为主，占颗粒总数的49.2％，烟尘集合体很少，占颗粒总数的3.6％。从元素组成来看，民用散煤燃烧排放颗粒物主要是炭质颗粒，占排放颗粒总数的77.2％，S元素在颗粒中较为常见，但大多数含量较低。从粒径分布来看，民用散煤燃烧排放颗粒物主要是微小颗粒物，绝大多数（81.0％）颗粒分布在<1 μm粒径范围内。民用散煤燃烧是大气污染物的重要来源之一，应制定相应的管控措施。

Microscopic characteristics of individual particles from residential raw coal combustion

In order to better understand the effect of particulate matter from residential combustion of raw coal, particulate samples were collected using a self-designed sampling collection system. The morphology and composition of individual particles were examined using a scanning electron microscope equipped for energy dispersive X-ray analysis (SEM-EDX). The results showed a variety of particles from the residential combustion of raw coal, including tar balls, fly ash, platy or blocky shaped carbonaceous particles, mineral particles, soot aggregates, and other particles. Spherical, or nearly spherical, particles were the predominant morphology, accounting for 49.2%. The amount of soot aggregates was low and only accounted for 3.6%. In their elementary composition, the particles were mainly carbonaceous (77.2%). Although the S concentration was low in particulate matter, elemental S appeared in most particles. The size distribution of the particulate matter from residential combustion of raw coal indicated that 81% of the particulate matter was<1 μm. The residential combustion of raw coal is one of the most important sources of atmospheric pollutants in China. Control measures should be developed to mitigate particulate matter emission from residential combustion of raw coal.