Physical Properties and Composition Detection of Biodiesel-diesel Fuel Blends

Abstract

Biodiesel is an oxygenated, sulfur-free, biodegradable, non-toxic, and environmentally friendly alternative diesel fuel. Biodiesel can be derived from renewable resources, such as vegetable oils, animal fats, and waste restaurant greases. One of the attractive characteristics of biodiesel is that its use does not require any significant modifications to the diesel engine, so the engine does not have to be dedicated for biodiesel. However, due to its different properties, biodiesel will cause some changes in the engine performance and emissions including lower power and higher oxides of nitrogen. Biodiesel can be blended in any proportion with petroleum-based diesel fuel and the impact of the changes is usually proportional to the fraction of biodiesel being used. If the biodiesel-diesel fuel blend level were known, these changes could be eliminated by the engine's electronic control system. The objective of this study was the investigation of the effect of biodiesel blend level on density, speed of sound, and isentropic bulk modulus at higher pressures, and at 20 °C and 40 °C. Also, blend detection with a commercial fuel composition sensor, and the effect of temperature, water, and alcohol on this detection was investigated.