Environmental Engineering Research

  • 제20권4호
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  • Pages.397-402
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  • 2015
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  • 1226-1025(pISSN)
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  • 2005-968X(eISSN)
대한환경공학회 (Korean Society of Environmental Engineers)
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Experimental studies on the diesel engine urea-SCR system using a double NOx sensor system

  • Tang, Wei (School of Automotive and Traffic Engineering, Jiangsu University) ;
  • Cai, Yixi (School of Automotive and Traffic Engineering, Jiangsu University) ;
  • Wang, Jun (School of Automotive and Traffic Engineering, Jiangsu University)
  • 투고 : 2015.08.19
  • 심사 : 2015.11.06
  • 발행 : 2015.12.31
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초록

SCR has been popularly approved as one of the most effective means for NOx emission control in heavy-duty and medium-duty vehicles currently. However, high urea dosing would lead to ammonia slip. And $NH_3$ sensor for vehicle emission applications has not been popularly used in real applications. This paper presents experimental studies on the diesel engine urea-SCR system by using a double NOx sensor system that is arranged in the downstream of the SCR catalyst based on ammonia cross-sensitivity. It was shown that the NOx conversion efficiency rised as $NH_3/NOx$ increases and the ammonia slip started from the $NH_3/NOx$ equal to 1.4. The increase of temperature caused high improvement of the SCR reaction rate while the space velocity had no obvious change. The ammonia slip was in advance as catalyst temperature or space velocity increase and the ammonia storage reduced as catalyst temperature or space velocity increase. The NOx real-time conversion efficiency rised as the ammonia accumulative storage increase and reached the maximum value gradually.

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참고문헌

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피인용 문헌

  1. Modeling, Analysis, and Experimental Testing of a Selective Catalytic Reduction Dosing System vol.5, pp.2169-3536, 2017, https://doi.org/10.1109/ACCESS.2017.2654487
  2. Comment on “Damages and Expected Deaths Due to Excess NOx Emissions from 2009 to 2015 Volkswagen Diesel Vehicles” vol.50, pp.7, 2015, https://doi.org/10.1021/acs.est.6b00856
  3. Characterization of Emission Factors Concerning Gasoline, LPG, and Diesel Vehicles via Transient Chassis-Dynamometer Tests vol.9, pp.8, 2015, https://doi.org/10.3390/app9081573
  4. Simulation Study of Ammonia Storage Characteristics of Selective Catalytic Reduction for Diesel Engines vol.38, pp.7, 2021, https://doi.org/10.1089/ees.2020.0197
  5. NOx sensor cross sensitivity model and simultaneous prediction of NOx and NH3 slip from automotive catalytic converters under real driving conditions vol.22, pp.10, 2015, https://doi.org/10.1177/1468087420966406