Enhancement of critical parameters of used transformer oil with naturally Activated Bentonite and investigation of vegetable oil performance with antioxidants

Transformers are the most vital components in power system. The common dielectrics used in transformers are solid, liquid and gaseous type. The major role of all the dielectrics is to provide sufficient insulation to the system to which it is used. Among them the function of liquid dielectric is to provide insulation and cooling. Traditionally mineral oil is used in transformer for decades and aged oils after life will be either recycled or sent to waste dump. Ageing reduces the critical properties of oil and either disposal causes environmental hazard. In this work, an attempt has been made to find an economic solution to enhance the aged transformer oil by treatment with acid Activated Bentonite. This paper reviews the properties of natural and synthetic antioxidants in vegetable oil which are the most significant active components that play an important role in reducing oxidation. Critical characteristics of oil such as Breakdown Voltage (BDV), viscosity, flashpoint and firepoint will be examined on aged transformer oil before and after treatment with Activated Bentonite. Based on the test results obtained, an economic solution is obtained and a recommendation is imparted to replace mineral oil with vegetable oil. This effort surely paves the way to green environment and postpones oil scarcity.