Abstract: In view of the many shortcomings of the vacuum filtering technology for transformer oil, the feasibility of applying the fixed bed adsorption process at room temperature and normal pressure to the dehydration of transformer oil was explored, the performance of different materials such as modified resin, 5A zeolite, activated carbon, and silica gel was investigated. The results showed that the performance of modified resin dehydrating agent was the best, followed by the anhydrous calcium chloride, the silica gel and 5A zeolite. When the water content of the feed oil was 33 μg/g, the initial water content at the outlet was less than 10 μg/g after fixed bed adsorption dehydration at WHSV of 30 h^-1. If taking the water content higher than 20 μg/g as the deactivation standard, the adsorption capacity of fresh modified resin was 96.03 mg/g. The modified resin could be used for many times, but the adsorption capacity would be lightly decreased after regeneration.

Key words: transformer oil, water adsorption, fixed bed, dehydrating agent, modified resin