School of Environment, Tsinghua University, Beijing 100084, China.
Sichuan Academy of Environmental Sciences, Chengdu 620041, China.
Int J Environ Res Public Health. 2022 Aug 3;19(15):9546. doi: 10.3390/ijerph19159546.
With the acceleration of urban construction, the pollutant emission of non-road mobile machinery such as construction machinery is becoming more and more prominent. In this paper, a portable emissions measurement system (PEMS) tested the emissions of eight different types of construction machinery under actual operating conditions and was used for idling, walking, and working under the different emission reduction techniques. The results showed that the pollutant emission of construction machinery is affected by the pollutant contribution of working conditions. According to different emission reduction techniques, the diesel oxidation catalyst (DOC) can reduce carbon monoxide (CO) by 41.6-94.8% and hydrocarbon (HC) by 92.7-95.1%, catalytic diesel particulate filter (CDPF) can reduce particulate matter (PM) by 87.1-99.5%, and selective catalytic reduction (SCR) using urea as a reducing agent can reduce nitrogen oxides (NO) by 60.3% to 80.5%. Copper-based SCR is better than vanadium-based SCR in NO reduction. In addition, the study found that when the enhanced 3DOC + CDPF emission reduction technique is used on forklifts, DOC has a "low-temperature saturation effect", which will reduce the emission reduction effect of CO and THC. The use of Burner + DOC + CDPF emission reduction techniques and fuel injection heating process will increase CO's emission factors by 3.2-3.5 and 4.4-6.7 times compared with the actual operating conditions.
随着城市建设的加速，建筑机械等非道路移动机械的污染物排放越来越突出。本文采用便携式排放测量系统（PEMS）在实际运行条件下测试了 8 种不同类型的建筑机械的排放情况，并对怠速、行走和不同减排技术下的工作状态进行了测试。结果表明，建筑机械的污染物排放受工况污染物贡献的影响。根据不同的减排技术，柴油氧化催化剂（DOC）可将一氧化碳（CO）降低 41.6-94.8%，将碳氢化合物（HC）降低 92.7-95.1%，催化式柴油颗粒过滤器（CDPF）可将颗粒物（PM）降低 87.1-99.5%，而以尿素为还原剂的选择性催化还原（SCR）可将氮氧化物（NO）降低 60.3%-80.5%。铜基 SCR 在降低 NO 方面优于钒基 SCR。此外，研究发现，当增强型 3DOC+CDPF 减排技术应用于叉车时，DOC 存在“低温饱和效应”，这将降低 CO 和 THC 的减排效果。使用燃烧器+DOC+CDPF 减排技术和燃油喷射加热过程将使 CO 的排放因子比实际运行条件下增加 3.2-3.5 倍和 4.4-6.7 倍。
