Abstract: Liquid leakage often occurs at both ends of the rotating shaft of the screen drum in the moisture exhaust system of the drum-type moisture regainer. Meanwhile, its bearings suffer from issues such as abnormal temperature rise, easy rusting leading to short service life, and difficulty in replacement and disassembly. Focusing on these problems, this paper analyzes the working principles of the moisture exhaust system and the screen drum of the drum-type moisture regainer, identifies the causes, and proposes an improvement scheme. By installing an air seal device, the liquid leakage at both ends of the rotating shaft of the screen drum in the moisture exhaust system can be effectively solved, the temperature rise of the rotating shaft bearings can be alleviated, the service life of the bearings can be prolonged, and the equipment failure rate and maintenance labor intensity can be reduced.