School of Transportation, Southeast University, Nanjing, China.
School of Medicine, Southeast University, Nanjing, China.
Sci Total Environ. 2021 Jun 1;771:145365. doi: 10.1016/j.scitotenv.2021.145365. Epub 2021 Jan 24.
This study implemented real-world tests in Nanjing, China for measuring emission factors (EFs) of air pollutants, including Carbon Monoxide (CO), Hydrocarbon (HC), Nitrogen Oxides (NO), and Particulate Matter (PM) from ten construction machines in three operational modes (idling, moving, and working) with a Portable Emission Measurement System. The idling mode shows the least variation of EFs, and its average CO EFs can be higher than the moving and working modes by 43% and 34%, respectively. The working mode generates the highest emission for all other pollutants with the highest variation. The EFs suggested by the Guide (an official guidebook for developing emission inventory in China) are in general lower than the measured EFs, and the gap becomes larger for older machines. The EFs of CO, NO, and PM of China Stage II machines are 24%, 120%, and 66% higher than those of the Guide, respectively. The differences go up as high as 126%, 1066%, and 559% for China Stage I machines, indicating the upgrade of engine technology from Stage I to Stage II, as well as the effect of machine deterioration. The result of this study reveals the effectiveness of stringent emission standards in controlling emissions from construction machines. High emissions from older machines emphasize the importance of a more rigorous machine replacement policy and a regulated maintenance strategy. The result also stresses the need to update the Guide with differentiated activity modes, region variations, and machine deterioration effects.
本研究在中国南京进行了实际测试，使用便携式排放测量系统测量了 10 种施工机械在 3 种运行模式（怠速、行驶和作业）下的空气污染物排放因子（EF），包括一氧化碳（CO）、碳氢化合物（HC）、氮氧化物（NO）和颗粒物（PM）。怠速模式的 EF 变化最小，其 CO EF 平均比行驶和作业模式分别高出 43%和 34%。作业模式下所有其他污染物的排放最高，变异最大。《指南》（中国制定排放清单的官方指南）建议的 EF 通常低于实测 EF，对于较旧的机器，差距更大。中国 II 阶段机器的 CO、NO 和 PM 的 EF 分别比《指南》高出 24%、120%和 66%。中国 I 阶段机器的 EF 差距高达 126%、1066%和 559%，这表明发动机技术从 I 阶段升级到 II 阶段，以及机器恶化的影响。本研究的结果表明，严格的排放标准在控制施工机械排放方面的有效性。较旧机器的高排放强调了更严格的机器更换政策和受监管的维护策略的重要性。研究结果还强调需要根据不同的活动模式、地区差异和机器恶化效应更新《指南》。
