Simultaneous Energy Recovery from Waste Polymers in Biodiesel and Improving Fuel Properties

Abstract

Although biodiesel has been known as an alternative fuel with specific advantages, it has also been investigated as a bio-solvent. In this study, biodiesel was applied as a bio-solvent for expanded polystyrene (EPS) and the kinetics of polymers’ dissolution in biodiesel was also investigated. Physicochemical parameters such as solubility parameters of EPS and biodiesel as well as polymer–solvent interaction were calculated at 21.13, 18.19 (MPa)1/2 and 0.343, respectively. From the energy recovery point of view, different parameters i.e. flash point, density, kinematic viscosity and dynamic viscosity were evaluated for the waste polymer-biodiesel blended diesel fuel. The results obtained revealed that the addition of EPS improved the biodiesel blended diesel fuel by increasing the flash point value while reducing the density and viscosity values. Moreover, the addition EPS alone generally increased the cloud point values, but co-addition of EPS and co-solvent (acetone) partially restored them to the original values. The overall engine test results were also in favor of the fuel blend as fuel consumption and emissions i.e. CO, CO2, NOx and smoke reduced considerably while the power generated remained approximately constant.