生物机油添加剂对柴油机气态污染物和颗粒物排放的影响

通过柴油机台架试验对某种生物机油添加剂进行排放性试验，确定其对柴油机尾气中各类污染物排放的影响。试验过程依据GB/T 18297—2001《汽车发动机性能试验方法》和GB 17691—2005《车用压燃式、气体燃料点燃式发动机与汽车排气污染物排放限值及测量方法(中国Ⅲ、Ⅳ、Ⅴ阶段)》，选定转速为2 000 r/min，进行发动机负荷特性试验，对尾气中的CO、THC、NO_x及颗粒物进行采集分析。结果表明：使用该生物机油添加剂后，CO和THC比排放量变化不大，只在低负荷时略有降低，最高可降低15%左右；NO_x比排放量有一定程度地升高，最多可升高15%；颗粒物比排放量降低较为明显，最大可削减53%；使用添加剂后，低负荷下可削减20~100 nm颗粒物的数浓度，中负荷下颗粒物数浓度排放变化不明显，高负荷下对20 nm以下和50 nm以上的颗粒物数浓度有削减作用，而20~50 nm的颗粒物数浓度会略有增加；随着发动机负荷增加，粒径分布图会逐渐升高变窄向左移动，使用添加剂会减缓这种变化趋势。

Preliminary Study on the Effect of the Bio-lubricating-oil-additive on the Gaseous Pollutants and Particulate Matter Emissions of Diesel Engine

The influence of the bio-lubricating-oil additive was determined by the emission experiment of the diesel engine bench test. The test procedure followed Road vehicles - Engine test code – Performance (GB/T 18297—2001) and Limits and measurement methods for exhaust pollutants from compression ignition and gas fuelled positive ignition engines of vehicles (Ⅲ, Ⅳ, Ⅴ) (GB 17691—2005). The engine speed of 2000 r/min was chosen to conduct the load characteristic test, with CO, THC, NOx and particulate matter in the exhaust gas collected and analyzed. The results show that the specific THC and CO emissions generally change little, and decreased only at low load, with the maximum reduction of about 15%. The specific NOx emission increased to a certain extent, with a maximum of rate 15%. The specific particulate concentration could be reduced significantly, with maximum rate of 53%. After using the additive, the particle number concentration of 20~100nm can be reduced at low load, the particle number concentration does not change obviously at medium load, the particle number concentrations below 20 nm and above 50 nm will be reduced at high load, while the particle number concentration of 20~50 nm will be slightly increased. With the increase of the engine load, the particle size distribution map will gradually increase and become narrow and shift to the left, and the use of additives will mitigate the trend.