Experimental studies on biodiesel production from leather industry waste fat and its effect on diesel engine characteristics

In this study, biodiesel was produced from the leather industry waste fat (LWFB), which is harmful to the environment and paid for its disposal. The methyl ester yield of the produced biodiesel was found to be 86.8%. LWFB was mixed with petroleum diesel fuel at 10% and 30% ratios and was named LWFB10 and LWFB30, respectively. The impacts of LWFB blends on a single cylinder four stroke cycle direct injection diesel engine operating characteristics were analyzed under different engine loads and speeds. The results showed that the LWFB blends began to be injected earlier than petroleum-based diesel fuel. The ignition delay was almost the same for all test fuels since the cetane number of LWFB is the same as the reference diesel fuel. The combustion duration of LWFB blends were shorter at all engine loads and speeds than diesel fuel. The peak values of cylinder pressure and heat release rate of LWFB blends were almost the same as the diesel fuel. It was noticed that the brake specific fuel consumption values of LWFB blends were higher than the reference diesel fuel at all engine loads and speeds and brake thermal efficiency was inversely proportional to brake specific fuel consumption as expected. It was also found that LWFB blends reduced smoke emissions but did not cause a significant change in NOx emissions.