Search

The rapid depletion of conventional fuel reserves and the increase in environmental pollution prompted the search for a sustainable energy solution. Biodiesel is one of the most promising energy substitutes with similar properties as conventional diesel fuel. Surplus availability of palm oil makes it suitable for biodiesel production. Due to the lack of availability of review articles that cover the entire process of palm biodiesel production and its optimum use in diesel engines, the authors were motivated to write this article. Cultivation parameters of palm trees, extraction of oil, and physicochemical properties of palm oil–based biodiesel are explained in this review. The production of palm biodiesel from raw oil can be done through pyrolysis, micro-emulsification, blending, hydro-esterification, and transesterification processes. For high biodiesel yield and less cost of operation, the transesterification method is adopted. The performance and emission parameters of diesel engines that operated on palm biodiesel and its blends are also explained. There is a decrease in brake thermal efficiency and an increase in brake-specific fuel consumption observed with the use of palm biodiesel in diesel engines. A reduction in CO and HC emissions and an increase in NOx emissions are found due to the oxygenating nature of palm biodiesel. This article provides the scientific approach to find out the optimum parameters for palm biodiesel production and its efficient use in compression ignition engines. [ABSTRACT FROM AUTHOR]

This study investigates the characterization of the hydroxy-diesel fueled compression ignition engine under dual fuel (DF) mode on a stationary modified engine. Hydroxy gas (HHO) is supplied along with diesel at three different flow rates of 0.25, 0.50, and 0.75 lpm. A significant reduction in emission parameters was obtained in carbon monoxide, unburnt hydrocarbon and smoke emission as ~58%, ~60%, and ~49%, respectively under the DF mode (at 0.75 lpm HHO and 10 kg load). However, a slight increment in nitrogen oxides (NO X) emission is observed due to the O 2 contents in HHO gas. It increases the reaction temperature and results in increasing the NO X emission. The brake thermal efficiency and brake specific energy consumption also improved and found to be ~6.5% and ~6% at the optimized condition. Combustion analysis shows the rate of pressure rise increased due to quicker combustion and decreased combustion duration. A numerical simulation has been performed to optimize the engine load and HHO flow rate using the Hybrid Entropy-VIKOR technique. In addition, a good agreement has been found between simulation and experimental values for performance and emission parameters. The results can be further improved by optimizing the engine operating parameters, i.e., injection pressure, compression ratio, and injection timing in the near future. Overall it can be concluded the HHO can be considered as a prominent alternative fuel for the CI engine with increased efficiency and lower emissions. Image 1 • Engine performance parameters (BTE and BSEC) improved with the hydroxy energy share. • Significant reduction in HC, CO, and smoke emission was observed with the HHO addition. • ROPR, in-cylinder MGT, and NHRR improved for D+0.75HHO mixture. • The engine operating parameters were optimized using the hybrid Entropy-VIKOR approach. [ABSTRACT FROM AUTHOR]