Comparison between PEE10 and PEE10-Bioethanol Blends on Performance and Emission Characteristics of a HSDI Diesel Engine

Abstract

Biofuels are an alternative fuel currently being developed to reduce the diesel-engine environmental impact. The release of carbon dioxide (CO2), nitric oxide (NO) and black smoke (BS) becomes an issue derived from diesel engines even in lean-mixture combustion causing an adverse effect to human health. The main aim of the research study is to present the use of biofuels, a mixture of diesel and 10 % palm oil ethyl ester (PEE10) and PEE10 blended with bioethanol from 5 to 20 %, compared with conventional diesel fuel. The biofuels were run on a high-speed direct injection diesel engine at a constant speed of 3,000 rpm under various loads. The use of PEE10 resulted in brake thermal efficiency (BTE) reduction by 2 % and brake specific fuel consumption (BSFC) incrementation by 8 %, but the exhaust emissions were lower than diesel, except for CO2 and NO. However, PEE10 engine performance was better and exhaust gas emissions were lower for both pollutants than diesel mixed with 10 % bioethanol. The investigation of PEE10 with increasing bioethanol revealed that the use of PEE10 blended with 5 % bioethanol (PEE10E5) can improve engine performance, while the BTE and BSFC were close to that of diesel, and exhaust emissions, especially CO2, NO and BS reduced. Moreover, BTE from PEE10E5 fueling increased by 2 % but BSFC was subtle increased, compared to PEE10. On the other hand, the increasing bioethanol from 10 to 20 % in PEE10 led to the more reduction in engine performance, but the engine pollutants were also continuously decreased. Specifically, the blend of PEE10 and 20 % bioethanol indicates that CO2, NO and BS were reduced by 10, 15 and 33 %, respectively, compared to diesel fuel.
 HIGHLIGHTS
 
 A mixture of diesel and 10 % palm oil ethyl ester (PEE10) has less exhaust emissions than diesel blended with 10 % palm oil methyl ester (PME10)
 PEE10 blended with 5 % bioethanol can improve engine performance, while the brake thermal efficiency and brake specific fuel consumption are close to that of diesel and PME10
 The increasing bioethanol from 10 to 20 % in PEE10 leads to the more reduction in engine performance, but the engine pollutants, especially carbon dioxide, nitric oxide and black smoke, are also continuously decreased
 
 GRAPHICAL ABSTRACT

Performance and Emission Characteristics of a High-Speed Diesel Engine Using a 20% Palm Oil Ester and Ethyl Alcohol Blend

“…However, the decrease in BTE was proportional to the increase in ethanol. POEE10 combined with ethanol additives indicated the continuous decline of various pollutants, such as CO2, NO, CO, and BS [2]. Similarly, POME10 properties were alleviated by blending 5% POEE and 5% butanol, combined with ethanol by up to 10%, which led to better fuel properties (FD and KV) and BTE than POME10.…”

“…Besides, adding ethanol resulted in a decrease in density and viscosity, as well as a change in cetane number, which led to improved engine characteristics [10,23]. The stability time was mainly for the diesel mixed with 5% ethanol and <20% FAMEs, whereas the blended stability was more than two months [2,26]. The diesel engine results using diesel mixed with <20% FAMEs and ethanol lowered the BTE compared to diesel.…”

“…In comparison, the BSFC increased when fueling the mixture of FAMEs and <20% ethanol. The NO, CO, and BS were continuously reduced with increasing ethanol [2,10,23,26]. Additionally, there were examinations of the operating behavior of the diesel engine at speeds and fixed loads running with the diesel and cottonseed methyl ester (CME) mixture in the proportion of 80:20 (namely CME20) combined with 10% ethanol.…”

“…[5][6]12]. The diesel blended with 10% POME (POME10) is used in this country to replace conventional diesel, namely regular diesel (B10) [2]. POME20 is mainly used as renewable energy for heavy diesel engines, as allowed by the Energy Ministry in Thailand [26].…”

“…Most combustion processes of petroleum-derived diesel, in terms of incomplete combustion of hydrocarbons, have released these products, which lead to the release of innumerable PM [1]. Nitrogen oxides (NOx), which consist mostly of nitric oxide (NO), are also a serious environmental concern because of their burden in smog formation [2]. Therefore, the various uses of oxygenated additives, especially fatty acid esters (FAEs) and alcohols, are getting attention due to renewable bio-based resources and high oxygen molecules providing the potential to reduce these emissions [3].…”