Performance of activated bentonite and carbon in reclaiming the properties of used mineral oil

In transformer, petroleum based mineral oil is used as insulation and coolant over many years. The environmental issue related with the present liquid insulation system is the disposal of used oil samples after prolonged service. The disposal problem arises due to the non biodegradable nature of mineral oil which may harmful and pollute the surrounding places. To avoid the disposal problems, this work focuses on study the influence of activated bentonite and carbon absorbents in reclaiming the properties of used mineral oil to analyze the re-usage characteristics of used mineral oil samples after reclaiming treatment. Reclaiming treatment is conducted with 500ml of used mineral oil and with individual combinations of 1g, 2g, 5g and 10g and blended combinations of two absorbents. The properties of oil samples such as breakdown voltage, flash point, fire point, viscosity, interfacial tension, water content and acidity are measured before and after reclamation treatment based on the international standards. From the investigation, it is understandable that the individual and blended combinations of activated absorbents have improved the properties of used mineral oil after treatment. The reclaimed oil sample has the potential to be reused as liquid insulation.