国内环保法规日趋严格，2019年1月1日起，全国范围内须供应符合国Ⅵ标准的车用汽、柴油，取消普通柴油标准。国Ⅵ标准车用柴油质量升级使炼厂的投资和运行成本大幅增加，国内少数炼厂按期全部升级为国Ⅵ柴油面临困难。船舶发动机与车用发动机的性能参数有明显差别，中速船舶使用国Ⅵ车用柴油质量过剩。因此，利用低十六烷值柴油馏分生产船用轻燃，既保障了内河船用油品的安全性、环保性，又降低了炼厂质量升级成本。

China's laws and regulations for environmental protection are becoming more and more stringent.China executes the national standard Ⅵ for vehicle gasoline and diesel from January 1st,2019,and old standards for gasoline and diesel under have been cancelled.The quality upgrading of diesel makes refineries face great cost increases in investment and operation.It is difficult for a few Chinese refineries to upgrade on schedule the production of diesel under the Ⅵ standard.The performance parameters of ship engines are significantly different from that of vehicle engines.Medium-speed ships need not to use diesel with a quality as high as that of standard Ⅵ.Therefore,low cetane number diesel fractions can be used to produce light fuel oil for ships,which can not only ensure the safety and cleanliness of fuels for inland river ships,but also help some refineries to save the cost in quality upgrading.