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Implementation of Portable Emissions Measurement Systems (PEMS) for the Real-driving Emissions (RDE) Regulation in Europe
Published on: December 4, 2016
Unregulated emissions from a diesel engine equipped with vanadium-based urea-SCR catalyst
Lei Jiang1, Yunshan Ge, Asad Naeem Shah
1School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China. jldna@bit.edu.cn
Journal of Environmental Sciences (China)
|July 13, 2010
Summary
This study shows that a vanadium-based urea selective catalytic reduction (SCR) system effectively reduces diesel engine emissions. The catalyst decreased particle numbers and volatile organic compounds (VOCs), and carbonyl compounds (CC).
Area of Science:
- Environmental Science
- Chemical Engineering
- Automotive Engineering
Background:
- Diesel engines are significant sources of air pollutants, including particulate matter, volatile organic compounds (VOCs), and carbonyl compounds (CC).
- Selective Catalytic Reduction (SCR) systems, particularly those using vanadium-based catalysts with urea, are employed to mitigate these emissions.
Purpose of the Study:
- To investigate the impact of a vanadium-based urea SCR catalyst on the number-size distribution of particles, VOCs, and CC emissions from a turbocharged diesel engine.
- To analyze the effectiveness of the SCR system under European steady-state cycle conditions.
Main Methods:
- A 4-cylinder turbocharged diesel engine was operated on an electric dynamometer using the European steady-state cycle.
- Emissions were analyzed using an electric low-pressure impactor for particle number-size distribution.
- Gas chromatograph/mass spectrometer and high-performance liquid chromatography were used for VOCs and CC analysis, respectively.
Main Results:
- The vanadium-based urea SCR catalyst significantly reduced the total number of particles, shifting their size distribution towards larger particles.
- A substantial decrease in VOCs was observed downstream of the catalyst, with a notable correlation between styrene and ethyl benzene conversion.
- Carbonyl compounds, including formaldehyde, acetaldehyde, acrolein, and acetone, were significantly abated by the SCR system, with benzene conversion increasing with catalyst temperature.
Conclusions:
- The vanadium-based urea SCR system demonstrates high efficiency in reducing particulate matter, VOCs, and CC emissions from diesel engines.
- The catalyst effectively alters particle size distribution and achieves significant reductions in key gaseous pollutants.
- The findings highlight the effectiveness of urea-SCR technology in improving air quality associated with diesel engine operation.
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