Performance and smoke opacity of compression-ignition engine using used-waste oil

The processing of waste oil into diesel-like fuel (DLF) is a challenging issue related to waste management and energy supply. This paper describes an experimental study of compression ignition (CI) engine using blended fuel between diesel and distillation product of used-waste oil. The objective is to evaluate the engine performance and smoke opacity caused by waste-derived fuel (WDF). Using an unmodified CI engine, pure distillation product and blends with diesel were applied to evaluate the engine performance ranging to engine speeds between 1000-5000 rpm. The results indicated that the physicochemical properties of WDF resemble diesel which could realistically be applied to CI engines. The lower viscosity of WDF provides the advantage of fuel movement and spray consistency inside the combustion chamber, which improved the combustion process. The average engine torque and power increase up to 3.22 and 2.89%, respectively. At the same time, the average fuel consumption reduces up to 8.31%. The WDF performs nearly as well as pure diesel when it comes to combustion. The increase in power and thermal efficiency is not particularly significant. However, it remains a viable alternative fuel for CI engines in terms of waste recycling.