승용 디젤기관에서 Urea-SCR 시스템의 NOX 저감 및 NH₃ slip 특성에 관한 실험적 연구

다국어 초록 (Multilingual Abstract)

The regulation of harmful emission including CO₂ is getting more strict recently according to greenhouse gases problem caused by increasing of CO₂ emission.
The Diesel engine provides many positive aspect such as higher thermal efficiency and less CO₂ emission. However, there are some problem on PM(Particulate Matters) and NOX emissions. PM has decreased by around 90% according to development of DPF technology. NOX reducing technique such as LNT, LNC, SCR has been developed and applied especially on heavy duty vehicle. But it is expected the NOX reducing technique is applied on passenger diesel vehicle, as well.
The Urea-SCR system is getting attention as the most effective NOX reducing technology without fuel efficiency incline, so that many advanced countries are developing this technology. Urea-SCR system sprays Urea- aqueous solution to take apart into N₂ and H₂O and emit into the atmosphere as reducing agent which is harmless. Injected Urea in front of SCR catalyst should be changed to NH₃ 100% required for NOX reduction in SCR system to maximize reducing efficiency.
In this study, it is purpose to look for the α ratio before the NH₃ slip at the load of engines by performance of the catalyst to find the maximum reduction rate of NOX. The α-ratio in the Urea-SCR system will be at one to one ratio by recognizing the NOX value in general. However, it is possible to inject NH₃ more by occlusion performance of the catalyst at the temperature condition so that there will be much reaction. As a result, there will be effect to improve the reduction rate of NOX. Therefore, it is able to exert much improved maximum performance the reaction of Urea-SCR by injecting NH₃ more as the α ratio before slipping to match the performance of the catalyst. Thus it becomes the injection strategy to reduce the nitrogen oxide. In conclusion, it is possible to create not only the exhaust regulations Euro-6 but also the Urea-SCR which satisfies Post Euro-6.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 실험장치 및 방법
• 3. 실험결과 및 고찰
• 4. 결론
• References