Investigation of Diesel Blends with Edible Vegetable Oils for Combustion in Swirl Burners

Experimentation of combustion characteristics in terms of maximum temperature of diesel-palm kernel oil (AGOPKO) blends and diesel-groundnut oil (AGOGO) blends using a locally fabricated liquid fuel swirl burner (LFSB) was attempted. The densities, viscosities and flashpoints of the pure liquids ad blends were obtained by measurement using Pensky-Marten's closed cup methods. Six swirl blades (curved-edge and straight-edge) were introduced into the combustion chamber and fired with 1:1, 1:2, 1:3 and 1:4 mix ratios of the blends at different swirl angles of 20°C, 30°C, 40°C, 50°C, and 60°C. The results showed that maximum temperatures were recorded at 50°C for straight-edge blades and 60°C for curved-edge blades. The study also revealed that the maximum temperatures of AGOGO blends were generally higher than those of AGOPKO blends due to the higher flash point and density of AGOPKO. It was also observed that curved-blade swirlers had better combustion characteristics than straight-blade swirlers, as the curved edges of the swirler increased the turbulence of the combustion process leading to higher temperatures. The optimum temperature was achieved using 60°C curved-edge blade swirler at a mix ratio of 1:1 AGOGO blend. ANOVA statistics revealed that blade type and fuel type have significant effect on maximum temperature of a swirl burner. The study further suggested the possibility of using straight vegetable oils as a partial replacement for fossil fuel in combustion chambers in lieu of prevailing rising prices of crude oil and adverse effect of its usage on the environment.