Transformer Oil – e-lesson #6 – Reconditioning and reclaiming of mineral oils
Hosted by: CS Narasimhan / Intermediate level
This lesson covers the reconditioning and reclaiming of used mineral transformer oils. It explains the importance of treating used oil to maintain transformer performance, as oil issues can account for up to 70% of transformer defects. The lesson outlines the general process for oil reconditioning, including filtration, heating, and dehydration. It discusses the use of adsorbents like silica gel and alumina to remove polar impurities through contact or percolation processes. Examples are provided showing the benefits of reclamation in improving oil properties like acidity and oxidation resistance. The lesson also covers new developments in reclamation techniques using specialized adsorbent materials. Finally, it presents methods to prevent or slow down oil aging, such as using thermosiphons and adsorption cartridges.
The content of this lesson is fully vendor agnostic but it is sponsored by Ergon.
The lesson will define the two processes – reconditioning and reclaiming of mineral oil. The criteria for deciding whether to carry out reconditioning or reclaiming will be discussed in detail, taking into consideration the IEC60422 standard.
This will be followed by a detailed discussion on how to carry out the two processes. The options available for reclaiming and the expected improved properties of reclaimed oils will be discussed too.
Keywords: reconditioning, reclaiming, IEC60422, ageing
The content of this lesson is fully vendor agnostic but it is sponsored by Ergon.
About the author
CS Narasimhan
Dr. Narasimhan is a Ph.D. in Chemistry with over 30 years of experience in Industrial R&D. While working as a technical director in a major oil company manufacturing transformer oils, he led project teams for developing and commercializing mineral oils for EHV applications and ester fluids. He is a member of several IEC and CIGRE committees dealing with transformer oils. He has several publications and patents to his credit.