非道路用柴油机半挥发性有机物排放特性

在一台国Ⅱ标准的非道路用柴油机上对半挥发性有机物（SVOCs）进行采样研究发现，非道路用柴油机排放气相SVOCs高于颗粒固相SVOCs，且在两相中的排放量均呈现随负荷增加而增加的趋势在气相和颗粒固相SVOCs中检出以烷烃为主，其次为多环芳烃类物质，包括2，3-二氢茚、四氢化萘、联苯、萘、芴、蒽、菲、芘等及其同系物．同时在对SVOCs中PAHs的研究中发现，柴油机排放的PAHs以气相为主，含量明显高于颗粒固相中PAHs；对比气固两相的浓度分布发现，气相PAHs中萘、苊烯、二氢苊、芴、菲、蒽为主，占气相PAHs质量比高达95％，而颗粒固相中PAHs则以菲、芘、荧蒽、屈、苯并（a）蒽等为主，其中苯并（a）蒽与屈在不同工况下质量比达80％以上；气相中PAHs环数以3环和2环为主，而大部分工况下颗粒固相中PAHs环数以4环为主，其次为3环．

Emission Characteristics of Semi-Volatile Organic Compounds from Non-Road Diesel Engine

Semi-volatile organic compounds （SVOCs） from the China II non-load diesel engine were sampled and analyzed. The results indicate that the SVOCs emissions in gas phase are higher than those in particulate mat- ters （PMs）. Meanwhile, the SVOCs emissions increase with the growing of load in both phases. Alkanes are the main compounds detected in SVOCs, followed by PAHs such as 2, 3-dihydro indene, tetrahydro naphthalene, biphenyl, naphthalene, fluorine and homologous series. The results also indicate that the PAHs emission proportion in gas phase is much higher than that in PMs. In gas phase, Nap, Acpy, Acp, Flu, PA and Ant are the main com- pounds, which account for more than 95% of all the PAHs emissions, while in PMs, Pyr, FL, CHR, BaA and Bap are the main compounds. BaA and CHR account for more than 80% of total PAHs in PMs. Most PAHs in gas phase have 2 or 3 benzene rings. However, in particulate matter 4 benzene ring compounds are the main ingredient, followed by 3 rings.