【摘要】 按汽油车国Ⅰ～Ⅳ催化器寿命5年或8万千米计算,国Ⅰ～Ⅲ车催化器寿命均到期,2014年以前国Ⅳ车的催化器也超过寿命,总计全国催化器寿命到期排放超标的汽油车约1. 2亿辆。研究表明:（1）催化器寿命到期后,汽油车的HC、CO和NO_x 的排放超过排放标准限值,是城市大气PM_{2. 5}和臭氧的主要来源之一。更换催化器后,HC、CO和NO_x 降低,汽车可节油8%～30%,城市PM_{2. 5}和臭氧能够降低。（2）国Ⅴ天然气公交车的NO_x 排放偏高主要是由于空燃比偏浓所致,采取加装SCR催化剂系统、NO_x 传感器和远程监控装置,将NO_x排放控制在国Ⅴ排放标准的限值内。国Ⅵ天然气车已达到准零排放,且动力性能和经济性均优,国Ⅵ排放标准的天然气公交车应作为城市新进公交车的首选。（3）国Ⅲ柴油车采用DOC+燃油喷射+CDPF技术路线最高可降低90%的PM_{2. 5}。（4）工程机械可采取和国Ⅲ柴油车相同的技术路线,降低排放。（5）国Ⅳ和国Ⅴ用柴油车装备SCR系统时NO_x排放本应达标,但存在净化系统作假或损坏,应安装远程监控系统进行监控。（6）需建立汽油车催化器按寿命更换、催化器市场准入、按国Ⅰ～Ⅴ排放标准限值检测制度;同时建立柴油车催化器、天然气车催化器的市场准入制度。更多还原

【Abstract】 The catalytic converters loaded in the gasoline vehicles of countries Ⅰ to Ⅲ and country Ⅳ before 2014 are all exceed the catalysts life,in accordance with the gasoline vehicles catalysts life of 5 years or 80 000 kilometers. In total,there are 120 million catalytic converters loaded in gasoline vehicles of countries Ⅰ to Ⅳ are exceed the catalysts life,resulting in excessive emission. The results show that:（1） The HC、CO and NO_x emissions of gasoline vehicles with catalytic converters at the end of their service life exceed the emission limits by several times,from dozens to hundreds times,it’s one of the main source of PM_{2. 5} and ozone in the urban atmosphere.After the replacement of catalytic converters,HC、CO and NO_x are reduced,the fuel saving effect of 8% to 30%,which can achieve the substantial reduction of PM_{2. 5} and ozone in Chinese cities.（2） The NO_x emissions of country Ⅴ natural gas bus on the high side is caused by the partial thick of air-fuel ratio,take with SCR catalyst system and NO_x sensor and remote monitoring devices,to control NO_x emission Ⅴ emissions standards within the limits. Country Ⅵ natural gas vehicles have reached zero emissions,and the dynamic performance and fuel economy are optimal,natural gas bus of country Ⅵ emissions standards should be taken as a city of choice for new buses.（3） The country Ⅲ diesel using DOC+fuel injection+CDPF technology can decrease 90% PM_{2. 5}.（4） Engineering machinery vehicles can take the same technical route as the country Ⅲ diesel vehicles to decrease the emissions.（5） Countries Ⅴ andⅥ diesel vehicles are equipped with SCR system,NO_x emissions should be standard. Actually,the purification system was falsified or damaged to bring the high amounts of emissions.It should be installed for monitoring remote monitoring system to real-time monitoring.（6） Catalytic converters should be replaced according to the life of a gasoline vehicle,and establish catalysts substitution system and market access system. Emission testing should be carried out according to the national emission standard limits. At the same time,establish the market access system of diesel and natural gas vehicle catalytic converters.更多还原