Abstract: A technique for providing in-place cleaning of a sealing structure for a rotating shaft in a materials processing apparatus wherein, during a cleaning operation, cleaning liquid is supplied in the form of a plurality of jets thereof from a source thereof to a rotating member having a sealing element, such as an O-ring, positioned about the rotating shaft. The cleaning fluid produced a scrubbing action on critical surfaces of the sealing structure to clean them. A plurality of jets of a drying fluid, such as pressurized air, is then supplied from a source thereof to the critical surfaces to remove excess cleaning liquid and to thoroughly dry such surfaces. The cleaning and drying operation can be activated to take place automatically and in-place using a pre-programmed processor without having to disassemble the sealing structure.