Performance and Energy Assessment of an Integrated Vacuum Refining System for Crude Palm Oil toward Electrical Insulating Applications

Abstract

The global transition toward environmentally sustainable technologies necessitates the development of biodegradable electrical insulating fluids. This study investigates the performance of a vacuum–fractional distillation reactor designed to convert high free fatty acid (FFA) crude palm oil (CPO) into a biodegradable electrical insulator. The reactor simultaneously performs degumming, deodorization, and vacuum spray drying, thereby enabling efficient purification and moisture removal. Experimental results demonstrated that even at a minimal processing time of 20 min, the breakdown voltage (BDV) exceeded 50 kV with the IEC 60156 (2018) test, with a peak performance of 59 kV at 50 min. The reactor achieved Specific Energy Consumption of 2.1 kWh/L. Thermal analysis indicated that 0.136 kWh was converted into useful heat, resulting in a thermal efficiency of approximately only 4.3%, primarily due to heat losses and irreversibility associated with the uninsulated laboratory-scale configuration, thereby indicating potential for improved heat utilization and energy recovery. The novelty of this work lies in the process integration, enabling treatment of high-FFA CPO in a single system, reducing operational complexity, and enables energy analysis. However, while the breakdown voltage requirement was satisfied, full compliance with IEC 62770 specifications necessitates further physicochemical characterization, which will be explored in future work.