Comparative assessment of n-butanol addition in CTL on performance and exhaust emissions of a CI engine

Sun, Wanchen; Sun, Yi; Guo, Liang; Zhang, Hao; Yan, Yuying; Zeng, Wenpeng; Lin, Shaodian

Abstract

Coal to liquid (CTL) is a diesel alternative fuel based on Fischer-Tropsch (FT) process, which has shown promising application value. Besides, as an oxygenated biofuel with high oxygen content and volatility, n-butanol can be blended with hydrocarbon fuels to improve engine performance. This study aims to investigate the effects of CTL/n-butanol blends on the performance of the compression-ignition (CI) engine, and to reveal the influence of combustion boundary conditions such as n-butanol blending ratio, the start of injection (SOI), and exhaust gas recirculation (EGR) on the combustion and emissions characteristics. The results show that blending n-butanol with CTL is beneficial to improve the fuel-gas mixture distribution in the cylinder, and the premixed combustion ratio (PCR) increases by 13.66% as the energy ratio of n-butanol increases to 30% (B30) compared with the pure CTL. CTL/n-butanol blends make particulate emission tend to be shifted towards nucleation mode and the particulate mass emission significantly reduced, especially the particulate mass of B30 reduce by 68.6%; meanwhile, the NOx emission shows an upward trend. Compared with n-butanol blended, adjusting the SOI impacts NOx emissions significantly, while its influence on the indicated thermal efficiency (ITE) and particulate emissions is relatively slight. Moreover, through the synergistic control of n-butanol addition and EGR, the trade-off relationship between NOx and particles is mitigated.

Citation

Sun, W., Sun, Y., Guo, L., Zhang, H., Yan, Y., Zeng, W., & Lin, S. (2021). Comparative assessment of n-butanol addition in CTL on performance and exhaust emissions of a CI engine. Fuel, 303, Article 121223. https://doi.org/10.1016/j.fuel.2021.121223

• Journal Article Type: Article
• Acceptance Date: Jun 6, 2021
• Online Publication Date: Jun 15, 2021
• Publication Date: 2021-11
• Deposit Date: Oct 23, 2023
• Publicly Available Date: Oct 23, 2023
• Journal: Fuel
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 303
• Article Number: 121223
• DOI: https://doi.org/10.1016/j.fuel.2021.121223
• Public URL: https://nottingham-repository.worktribe.com/output/25646835
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0016236121011029