Experimental investigation of the effects of turkey rendering fat biodiesel on combustion, performance and exhaust emissions of a diesel engine

Abstract

In this study, turkey rendering fat biodiesel (TRFB) was produced by two-step reactions (esterification and transesterification). Fatty acid ester content and yield in methyl ester were found 96.7% and 88.5% respectively. TRFB was blended with diesel fuel (DF) at 10%, 20%, and 50% (v/v) proportion to obtain fuel blends named TRFB10, TRFB20 and TRFB50, respectively. The effects of TRFB blends on the combustion, performance and exhaust emissions of a direct injection single cylinder diesel engine were systematically investigated under different engine loads, at the constant engine speed of 2000 rpm. The results show that the maximum cylinder pressure (CPmax) and maximum heat release rate (HRRmax) values of the TRFB blends were higher than those of DF for all engine loads because of the low cetane number of the TRFB and the rapid burning of the fuel accumulated in the combustion chamber during the long ignition delay. It was observed that the DF has a higher exhaust gas temperature than the biodiesel blends at high loads because of the longer combustion duration of the DF. The brake thermal efficiency (BTE) values of the TRFB blends were found to be lower than those of DF at all loads. Since the heating value of the biodiesel is lower than that of DF, it was observed that the brake specific fuel consumption (BSFC) values of TRFB blends are higher compared to those of DF. In addition, TRFB10, TRFB20 and TRFB50 blends reduce smoke opacity approximately 20%, 25% and, 40%, respectively, and cause a slight increase in nitrogen oxide (NOx) emissions.