柴油机是一种空气污染源。柴油机运转时排出的废气有害物包括一氧化碳(CO),碳氢化合物(HC),氮氧化物(NO_x),碳烟、颗粒物、二氧化硫(SO_2)和硫酸盐,醛类以及苯(α)芘等。 现今各国标准中已对CO、HC,NO_x三种有害组分以及排气烟度加以限制,美国已提出颗粒物排放的建议标准,正准备对颗粒物排放加以控制。CO、HC和NO_x三种组分通常称为有法规控制的有害组分,其它有害组分则称为无法控制的组分。 本文综合分析了现代柴油机,特别是车用柴油机排出的各种有害物含量的变化范围。 Diesel is a source of air pollution. Exhaust emissions from diesel engines include carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO x), soot, particulates, sulfur dioxide (SO 2) and sulfates, aldehydes and benzene (α) . Nowadays national standards have limited the three harmful components of CO, HC and NO_x as well as the exhaust smoke. The United States has proposed a standard for the emission of particulate matter and is preparing to control the emission of particulate matter. The three components, CO, HC and NO_x, are commonly referred to as hazardous components under regulatory control and other hazardous components are called uncontrollable components. This article comprehensively analyzes the range of variation of the content of various harmful substances discharged by modern diesel engines, especially diesel engines for vehicles.