TY - JOUR
T1 - Nox emission from diesel vehicle with SCR system failure characterized using portable emissions measurement systems
AU - Su, Sheng
AU - Ge, Yunshan
AU - Zhang, Yingzhi
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/7/1
Y1 - 2021/7/1
N2 - Nitrogen oxides (NOx) emissions from diesel vehicles are major contributors to increasing fine particulate matter and ozone levels in China. The selective catalytic reduction (SCR) system can effectively reduce NOx emissions from diesel vehicles and is widely used in China IV and V heavy-duty diesel vehicles (HDDVs). In this study, two China IV HDDVs, one with SCR system failure and the other with a normal SCR system, were tested by using a portable emissions measurement system (PEMS). Results showed that the NOx emission factors of the test vehicle with SCR system failure were 8.42 g/kW·h, 6.15 g/kW·h, and 6.26 g/kW·h at loads of 0%, 50%, and 75%, respectively, which were 2.14, 2.10, and 2.47 times higher than those of normal SCR vehicles. Emission factors, in terms of g/km and g/kW·h, from two tested vehicles were higher on urban roads than those on suburban and motorways. The NOx emission factor of the vehicle with failed SCR system did not meet the China IV emission standard. The time-weighted results for normal SCR vehicle over the three road types show that, except for NOx emission factor 12.17% higher than the China IV limit at 0% load, the emission values are 16.21% and 27.54% below the China IV standard limit at 50% load and 75% load, respectively. In general, with higher load, NOx emissions (in terms of g/kW·h) from the tested vehicle decreased. Furthermore, NO/NOx concentrations of both vehicles with normal and failed SCR systems showed a decreasing trend with the increase in load.
AB - Nitrogen oxides (NOx) emissions from diesel vehicles are major contributors to increasing fine particulate matter and ozone levels in China. The selective catalytic reduction (SCR) system can effectively reduce NOx emissions from diesel vehicles and is widely used in China IV and V heavy-duty diesel vehicles (HDDVs). In this study, two China IV HDDVs, one with SCR system failure and the other with a normal SCR system, were tested by using a portable emissions measurement system (PEMS). Results showed that the NOx emission factors of the test vehicle with SCR system failure were 8.42 g/kW·h, 6.15 g/kW·h, and 6.26 g/kW·h at loads of 0%, 50%, and 75%, respectively, which were 2.14, 2.10, and 2.47 times higher than those of normal SCR vehicles. Emission factors, in terms of g/km and g/kW·h, from two tested vehicles were higher on urban roads than those on suburban and motorways. The NOx emission factor of the vehicle with failed SCR system did not meet the China IV emission standard. The time-weighted results for normal SCR vehicle over the three road types show that, except for NOx emission factor 12.17% higher than the China IV limit at 0% load, the emission values are 16.21% and 27.54% below the China IV standard limit at 50% load and 75% load, respectively. In general, with higher load, NOx emissions (in terms of g/kW·h) from the tested vehicle decreased. Furthermore, NO/NOx concentrations of both vehicles with normal and failed SCR systems showed a decreasing trend with the increase in load.
KW - After-treatment failure
KW - NOx
KW - Portable emissions measurement system (PEMS)
KW - Urea-selective catalytic reduction (SCR)
UR - http://www.scopus.com/inward/record.url?scp=85109559534&partnerID=8YFLogxK
U2 - 10.3390/en14133989
DO - 10.3390/en14133989
M3 - Article
AN - SCOPUS:85109559534
SN - 1996-1073
VL - 14
JO - Energies
JF - Energies
IS - 13
M1 - 3989
ER -
