Performance Testing Of Liquid Fuel Produced From Waste Plastics In Diesel Engine

Abstract

Conventional fossil fuels are widely used as a source of energy for prime movers like IC Engines. The efficient prime movers like diesel engines are usually find applications in a wide array of areas, including industrial, agricultural and transport sectors. However, the demand for diesel and other petroleum-based fuels across the globe, especially in developing nations such as Ethiopia, has been rising steadily leading to concerns for long-term energy security. In addition, the increased use of hydrocarbon fuels leads to air pollution, both at local and regional levels, ultimately leading to climate change. Due to a combination of these factors, various research initiatives aimed at developing suitable alternative sources of energy continue to be accepted and this is one of such initiatives. This study investigated the appropriateness of the use of waste plastic oil as an alternative fuel for diesel engine and effect of blending waste plastic oil with diesel (B0, B20, B30 and B50) on fuel properties, engine performance and engine emissions characteristics. The liquid fuel was produced using pyrolysis process from waste plastic collected from Adama and the test was conducted on a single-cylinder direct injection diesel engine in Addis Ababa Science and Technology University. Fuel Properties like density and kinematic viscosity were evaluated and compared to those of baseline data obtained with pure diesel (B0). Engine performance like brake power (Pb), brake torque (Tb) and brake specific fuel consumption (bsfc) and emissions such as CO, CO2, HC and NOx are also evaluated. Both density and kinematic viscosity observed to be decreasing as the waste plastic fuel proportion increases in the blend and the values are less than that of pure diesel but higher than the minimum standard value up to B50. The maximum gap between the pure diesel and its blend at peak points for brake power and brake torque is 11.9% (B30 at 3600 rpm) and 16.3% (B50 at 1150 rpm) respectively in which diesel fuel is on the top. However, in terms of bsfc, B50 gives the lowest consumption which can reduce up to 7.4% of fuel. In case of emission, the waste plastic blend improves NOx emission (except B50), carbon dioxide, and unburned hydrocarbons by 2.8% (B20 at 3600 rpm), 9.8% (B50 at 1300 rpm), and 18.7% (B300 at 1000 rpm) respectively but the emissions of CO are slightly higher at low speeds and almost close to each other at higher engine speeds.