Characteristics of typical non-road machinery emissions in China by using portable emission measurement system

• Published in: The Science of the total environment 2012-10, Vol.437, p.255-261
• Main Authors: Fu, Mingliang, Ge, Yunshan, Tan, Jianwei, Zeng, Tao, Liang, Bin
• Format: Article
• Language: English
• Subjects: Air Pollutants - analysis; Applied sciences; Atmospheric pollution; China; Cities; Construction equipment; Construction Industry; Dispersed sources and other; Emission factor; Environmental Monitoring - instrumentation; Environmental Monitoring - methods; Exact sciences and technology; Hydrocarbons - analysis; Nitrogen Oxides - analysis; Non-road machinery; PEMS; Pollution; Pollution sources. Measurement results; Vehicle Emissions - analysis
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2012.07.095

Non-road machinery, especially construction equipment could be an important pollutant source of the deterioration in air quality in Chinese urban areas due to its large quantity and to the absence of stringent emission requirements. In this study, emission tests were performed on 12 excavators and 8 wheel loaders by using portable emission measurement system (PEMS) to determine their emission characteristics. The typical operating modes were categorized as idling mode, moving mode and working mode. Compared with those during idling and moving modes, the average time-based emission factors during working mode of HC were 2.61 and 1.27 times higher, NOx were 3.66 and 1.36 times higher, and PM were 4.05 and 1.95 times higher, respectively. Under all conditions, categories of the measured emissions increased with the rise in engine power. Compared with those of Stage I emission standard equipment, gaseous emissions and PM emitted from Stage II emission standard equipment were lower. The results indicated that, from Stage I to Stage II, the average reductions of HC, NOx and PM were 56%, 37% and 29% for the working mode, respectively. Those results also demonstrated the effectiveness of emission control regulation and the improvement of emission control technology. The data and tests show that the longer the accumulated working hours, the higher HC and NOx average fuel-based emission factors are. The emissions measured from the construction vehicles employed in this study were higher than the data collected in previous studies, which shows that it is critical for the government to put into effect more stringent emission regulations to further improve the air quality in Chinese urban areas. ► Gaseous and PM emissions of 12 excavators and 8 wheel loaders were measured using PEMS. ► Time-based and fuel-based emission factors for idling, moving and working operating modes were acquired. ► Results showed that equipment with longer accumulated engine hours typically emitted higher levels of both HC and NOx. ► Fuel-based emission factors of the wheel loaders were higher than those of the excavators for the working mode. ► Compared with previous study, construction equipment in China had higher emissions on mostly pollutants for the working mode.