Analysis of the effects of cetane improver addition to diesel on engine performance and emissions

Abstract

The high cetane number of the fuel used in diesel engines is extremely important as it provides some improvements in combustion in the cylinder. Therefore, the addition of cetane improver to diesel fuel has been highly preferred in recent years. In this study, the effects of 2-ethylhexyl nitrate (EHN) addition, a cetane improver, on compression ignition engine performance and emissions were analyzed at various engine loads. Four different fuels were used in the experiments as 100% diesel (D100), 99% diesel + 1% EHN (D99EHN1), 98% diesel + 2% EHN (D99EHN2) and 97% diesel + 3% EHN (D99EHN3). The results obtained from the experiments showed that the addition of 2-EHN positively affected the brake thermal efficiency (BTHE), hydrocarbon (HC) and carbon monoxide (CO) values, while the brake specific fuel consumption (BSFC), nitrogen oxide (NOx) and smoke emission levels were negatively affected. With high engine load, 2-EHN supplement marginally rises NOx emissions but significantly declines HC and CO emissions. EHN addition had small impacts on BSFC. Compared to D100 fuel, the highest BTHE value was obtained by D99EHN2 fuel, with an increase of 11.57% at 3000-Watt load value. With the D97EHN3 fuel, compared to diesel, HC emission decreased 60.61%, while CO emission decreased 31.25%. The results show that the 2-EHN cetane improver can be used successfully in a diesel engine.

Keywords

• 2-ethylhexyl nitrate
• cetane improver
• diesel engine
• performance
• emission

References

1. Fayyazbakhsh, A. and Pirouzfar, V., “Investigating the influence of additives-fuel on diesel engine performance and emissions: Analytical modeling and experimental validation,” Fuel, vol. 171, no. 167–177, 2016.
2. H. M. Goga, C., Chauhan, B. S., Mahla, S. K. and Cho, “Performance and emission characteristics of diesel engine fueled with rice bran biodiesel and n-butanol,” Energy Reports, vol. 5, pp. 78–83, 2019.
3. Aydın, M., Uslu, S., Çelik, M. B., “Performance and emission prediction of a compression ignition engine fueled with biodiesel-diesel blends: A combined application of ANN and RSM based optimization,” Fuel, vol. 269, 2020.
4. Mahlia, T.M.I., Syazmi, Z.A.H.S., Mofijur, M., Abas, A.E.P., Bilad, M.R., Ong, H.C., Silitonga, A.S., “Patent landscape review on biodiesel production: Technology updates,” Renew. Sustain. Energy Rev., vol. 118, p. 109526, 2020.
5. S. Simsek, “Effects of biodiesel obtained from Canola, sefflower oils and waste oils on the engine performance and exhaust emissions,” Fuel, vol. 265, p. 117026, 2020.
6. Abdollahi, M., Ghobadian, B., Najafi, G., Hoseini, S.S., Mofijur, M., Mazlan, M., “Impact of water – biodiesel – diesel nano-emulsion fuel on performance parameters and diesel engine emission,” Fuel, vol. 280, p. 118576, 2020.
7. Şimşek, S., Saygın, H., Özdalyan, B., “Improvement of Fusel Oil Features and Effect of Its Use in Different Compression Ratios for an SI Engine on Performance and Emission,” Energies, vol. 13, no. 7, p. 1824, 2020.
8. Uslu, S. and Celik, M. B., “Combustion and emission characteristics of isoamyl alcohol-gasoline blends in spark ignition engine,” Fuel, vol. 262, 2020.

9. L. Anantha Raman, B.Deepanraj, S.Rajakumar, and V.Sivasubramaniand, “Experimental investigation on performance, combustion and emission analysis of a direct injection diesel engine fuelled with rapeseed oil biodiesel,” Fuel, vol. 246, pp. 69–74, 2019.
10. F. Yang, H. Cho, H. Zhang, J. Zhang, and Y. Wu, “Artificial neural network (ANN) based prediction and optimization of an organic Rankine cycle (ORC) for diesel engine waste heat recovery,” Energy Convers. Manag., vol. 164, no. February, pp. 15–26, 2018.
11. S. Simsek, S. and Uslu, “Comparative evaluation of the influence of waste vegetable oil and waste animal oil-based biodiesel on diesel engine performance and emissions,” Fuel, vol. 280, p. 118613, 2020.
12. Sun, C.S., Liu, Y., Qiao, X., Ju, D., Tang, Q., Fang, X., Zhou, F., “Experimental study of effects of exhaust gas recirculation on combustion, performance, and emissions of DME-biodiesel fueled engine,” Energy, vol. 197, p. 1172333, 2020.
13. Simsek, S. and Uslu, S., “Determination of a diesel engine operating parameters powered with canola, safflower and waste vegetable oil based biodiesel combination using response surface methodology (RSM),” Fuel, vol. 270, 2020.
14. Noushabadi, A.S., Dashti, A., Raji, M., Zarei, A., Mohammadi, A.H., “Estimation of cetane numbers of biodiesel and diesel oils using regression and PSO-ANFIS models,” Renew. Energy, vol. 158, pp. 465–473, 2020.
15. S. Simsek and S. Uslu, “Investigation of the effects of biodiesel/2-ethylhexyl nitrate (EHN) fuel blends on diesel engine performance and emissions by response surface methodology (RSM),” Fuel, vol. 275, p. 118005, Sep. 2020.
16. Uslu, S. and Aydın, M., “Effect of operating parameters on performance and emissions of a diesel engine fueled with ternary blends of palm oil biodiesel/diethyl ether/diesel by Taguchi method,” Fuel, vol. 275, p. 117978, 2020.
17. Jeevanantham, A. K., Reddy, D. M., Goyal, N., Bansal, D., Kumar, G., Kumar, A., Nanthagopal, K., Ashok, B., “Experimental study on the effect of cetane improver with turpentine oil on CI engine characteristics,” FUEL, vol. 262, 2020.
18. Pan, M., Huang, R., Liao, J., Ouyang, T., Zheng, Z., Lv, D., Huang, H., “Effect of EGR dilution on combustion, performance and emission characteristics of a diesel engine fueled with n-pentanol and 2-ethylhexyl nitrate additive,” Energy Convers. Manag., vol. 176, pp. 246–255, 2018.
19. Imdadul, H. K., Masjuki, H. H., Kalam, M. A., Zulkifli, N. W. M., Alabdulkarem, A., Rashed, M. M., Ashraful, A. M., “Influences of ignition improver additive on ternary (diesel-biodiesel-higher alcohol) blends thermal stability and diesel engine performance,” Energy Convers. Manag., vol. 123, pp. 252–264, 2016.
20. Chen, G., Di, L., Zhang, Q., Zheng, Z., Zhang, W., “Effects of 2,5-dimethylfuran fuel properties coupling with EGR (exhaust gas recirculation) on combustion and emission characteristics in common-rail diesel engines,” Energy, vol. 93, no. 1, pp. 284–293, 2015.
21. Qian, W., Huang, H., Pan, M., Huang, R., Tong, C., Guo, X., Yin, J., “Effects of 2-ethylhexyl nitrate and post-injection strategy on combustion and emission characterizes in a dimethyl carbonate/diesel blending engine,” FUEL, vol. 263, 2020.
22. Ickes, A.M., Bohac, S.V., Assanis, D.N., “Effect of 2-Ethylhexyl Nitrate Cetane Improver on NOx Emissions from Premixed Low-Temperature Diesel Combustion,” Energy &Fuels, vol. 23, no. 10, pp. 4943–4948, 2009.
23. Serena, F.S., Nicolau, E., Favreau, G., Jouanneau, Y., Marchal, R., “Biodegradability of 2-ethylhexyl nitrate (2-EHN), a cetane improver of diesel oil,” Biodegradation, vol. 20, pp. 85–94, 2009.
24. Chen, X., Mark, E., Fuller, C., Goldsmith, F., “Decomposition kinetics for HONO and HNO2,” React. Chem. Eng., vol. 4, no. 2, pp. 323–333, 2019.
25. Li, X., Qin, S., Huang, X., Liu, H., “Multi-component effect and reaction mechanism for low-temperature ignition of kerosene with composite enhancer,” Combust. Flame 2019, pp. 401–410, 2019.
26. Pan, M., Qian, W., Huang, R., Tong, C., Huang, H., Xu, L., Hao, B., “Effects of dimethyl carbonate and 2-ethylhexyl nitrate on energy distribution, combustion and emissions in a diesel engine under different load conditions,” Energy Convers. Manag., vol. 199, 2019.
27. Kuszewski, H., “Effect of adding 2-ethylhexyl nitrate cetane improver on the autoignition properties of ethanol–diesel fuel blend – Investigation at various ambient gas temperatures,” Fuel, vol. 224, pp. 57–67, 2018.
28. Imdadul, H. K., Masjuki, H. H., Kalam, M. A., Zulkifli, N. W. M., Kamruzzaman, M., Shahin, M. M., Rashed, M. M., “Evaluation of oxygenated n-butanol-biodiesel blends along with ethyl hexyl nitrate as cetane improver on diesel engine attributes,” J. Clean. Prod., vol. 141, pp. 928–939, 2017.
29. Kumar, H., Sarma, A. K., Kumar, P., “A novel approach to study the effect of cetane improver on performance, combustion and emission characteristics of a CI engine fuelled with E20 (diesel – bioethanol) blend,” Sustain. Chem. Pharm., vol. 14, 2019.
30. Han, Z., Li, B., Tian, W., Xia, Q., Leng, S., “Influence of coupling action of oxygenated fuel and gas circuit oxygen on hydrocarbons formation in diesel engine,” Energy, vol. 173, pp. 196–206, 2019.
31. Gülder, Ö. L., Glavincevski, B., “Ignition quality determination of diesel fuels from hydrogen type distribution of hydrocarbons,” Combustion and Flame., vol. 63, no 1-2, pp. 231-238, 1986.
32. Cataluna, R. and da Silva, R., “Effect of Cetane Number on Specific Fuel Consumption and Particulate Matter and Unburned Hydrocarbon Emissions from Diesel Engines,” Journal of Combustion, 2012.
33. Obeid, F., Van, T.C., Horchler, E.J., Guo, Y., Verma, P., Milijevic, B., Brown, R.J., Ristovski, Z., Bodisco, T.A., Rainey, T., "Engine performance and emissions of high nitrogen-containing fuels", Fuel, vol. 264, 2020.
34. Simsek, S. and Uslu, S., " Experimental study of the performance and emissions characteristics of fusel oil/gasoline blends in spark ignited engine using response surface methodology", Fuel, vol. 277, pp. 118182, 2020.
35. Nautiyal, P., Subramanian, K.A., Dastidar, M.G., Kumar,A., "Experimental assessment of performance, combustion and emissions of a compression ignition engine fuelled with Spirulina platensis biodiesel", Energy, vol. 193, pp. 116861, 2020.
36. Şen, M., Emiroğlu, A. O., Keskin, A., "Production of Biodiesel from Broiler Chicken Rendering Fat and Investigation of Its Effects on Combustion, Performance, and Emissions of a Diesel Engine", Energy & Fuels, vol. 32, no 4, pp. 5209–5217, 2018.
37. Rizwanul Fattah, I. M., Masjuki, H. H., Kalam, M. A., Wakil, M. A., Rashedul, H. K., Abedin, M. J., "Performance and emission characteristics of a CI engine fueled with Cocos nucifera and Jatropha curcas B20 blends accompanying antioxidants", Industrial Crops & Products, vol. 57, pp. 132–140, 2014.