内河船舶柴油机的实际排放特征

Emissions Characteristics of Diesel Engines for Inland Waterway Vessels in China

利用由SEMTECH-DS和ELPI组成的PEMS(车载排放测试系统),对京杭运河江苏段具有代表性的12艘内河船舶进行实际排放测试,分析不同工况下CO、HC、NOx和PM的排放.结果表明:巡航工况下CO、HC和PM排放速率分别为0.093、0.019、0.018 gs,低于进、出港工况;而NOx排放速率为0.347 gs,分别为出港和进港工况的1.66和2.90倍;不同工况外排NO占NOx比例不同,其中巡航工况中外排NO所占比例最大(达到96.7%),而出港和进港工况则分别为93.6%和93.1%.随着负荷增加,船舶CO、HC、NO和PM的排放浓度增大,高负荷下CO、HC、NOx、PM的排放浓度比低负荷分别增高89.23%、29.51%、44.72%和229.49%.由颗粒物的粒径分布可知,3种工况下颗粒物数浓度的粒径分布呈双峰分布,分别对应核模态和积聚模态,粒径<120 nm的颗粒物数浓度占总浓度的99.84%以上,PM2.5数浓度占PM10比例均超过99.9%.

Transient mode emissions from twelve inland ships were measured using a portable emissions measurement system （PEMS）. The results show that the emissions of CO, H C, and PM during cruise mode were 0. 093,0. 019, and 0. 018 g/s, respectively, lower than the emissions in maneuvering and departure modes. In contrast, the NOx emission factor in cruise mode was 0. 347 g/s, which was 1.66 and 2.90 times of the emissions in maneuvering and departure modes, respectively. The ratios of NO to NO varied under different conditions. The proportion of NO was maximum in cruise mode （ reaching 96. 7% ）, while the proportions in maneuvering and departure modes were 93.6% and 93.1% , respectively. CO, HC, NO, and PM emissions from the vessel increased with load; the emissions concentrations in high load mode were 89. 23%, 29.51%,44.72%, and 229.49% higher, respectively than those in low load mode. Particle number （ PN ） distribution analysis indicated that the number distribution showed a double peak logarithm distribution consisting of accumulation mode/coarse mode and nucleation mode/accumulation mode. Particles smaller than 120 nm consisted of 99.84% of all particles by number. Among PM10 particles, 99.9% were PM2.5.