Document Type : Research Paper
Department of Industrial and Digital Innovation, University of Palermo, Viale delle Scienze, 90128, Palermo, Italy.
Istituto Nazionale di Geofisica e Vulcanologia - Osservatorio Nazionale Terremoti, Roma (RM), Italy.
An experimental study was carried out on a large stationary compression ignition engine to evaluate the long-term compatibility and durability issues associated with the use of crude palm oil as fuel. Two different preheating temperatures (60 and 80 °C) were adopted to assess the potential improvements related to lower fuel viscosity. The results obtained, in terms of in-cylinder carbon deposits and engine wear, were compared with the results obtained using ordinary diesel fuel. For each fuel and preheating temperature, the engine was operated for 300 consecutive h, during which several engine lubricant samples were collected and analysed to determine soot and fuel contaminations, viscosity alterations, and the presence of different wear-related metals (measured by atomic absorption spectroscopy). At the end of each 300 h endurance test, the carbon deposits were scraped from engine cylinders and examined through thermogravimetric analysis (TGA). It was found that the use of crude palm oil caused a remarkable increment of in-cylinder deposits formation compared with ordinary diesel. The lubricant analysis also revealed a faster viscosity degradation and consequent stronger engine wear, above all with the lower preheating temperature. The results obtained confirmed that continuous engine operation (i.e., without a complete lubricant change) should be carefully reduced when fuelling with crude palm oil. Moreover, the findings obtained herein confirmed the favourable impacts of fuel preheating at 80 °C compared to 60 °C, i.e., reduced carbon deposits by 27% and extended engine operation time by 30%.
- Effect of crude palm oil preheating temperature was investigated on a modern large CI engine.
- Engine wear and carbon deposits were evaluated during 300 h nominal power operation.
- Preheating at 60 °C produced higher carbon deposits and faster lubricant degradation.
- Compared with 60 °C, preheating at 80 °C reduced carbon deposits by 27% and extended engine operation time by 30%.