Mileage of taxi fleets is significantly higher than regular passenger vehicles in China, which might trigger greater tailpipe emissions of air pollutants. To investigate their real-world gaseous emissions, we applied portable emissions measurement systems (PEMSs) to test 44 gasoline and 24 bi-fuel taxis in seven cities. Our real-world measurement results indicated that a major part of the tested China 3 and China 4 gasoline taxis, especially the samples with high mileage (>300,000 km), far exceeded the corresponding emission limits of NO, THC and CO.
View Article and Find Full Text PDFThe challenge to mitigate real-world emissions from vehicles calls for powerful in-use compliance supervision. The remote on-board diagnostic (OBD) approach, with wireless data communications, is one of the promising next-generation monitoring methods. We collected second-by-second profiles of carbon dioxide (CO) and nitrogen oxides (NO) emissions, driving conditions and engine performance for three conventional diesel and three hybrid diesel buses participating in a remote OBD pilot program in Nanjing, China.
View Article and Find Full Text PDFEnviron Sci Technol
December 2015
Controlling nitrogen oxides (NOx) emissions from diesel passenger cars during real-world driving is one of the major technical challenges facing diesel auto manufacturers. Three main technologies are available for this purpose: exhaust gas recirculation (EGR), lean-burn NOx traps (LNT), and selective catalytic reduction (SCR). Seventy-three Euro 6 diesel passenger cars (8 EGR only, 40 LNT, and 25 SCR) were tested on a chassis dynamometer over both the European type-approval cycle (NEDC, cold engine start) and the more realistic Worldwide harmonized light-duty test cycle (WLTC version 2.
View Article and Find Full Text PDFAccelerated carbonation of alkaline wastes including municipal solid waste incinerator bottom ash (MSWI-BA) and the cold-rolling wastewater (CRW) was investigated for carbon dioxide (CO2) fixation under different operating conditions, i.e., reaction time, CO2 concentration, liquid-to-solid ratio, particle size, and CO2 flow rate.
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