A seal for a rotary shaft extending from a container containing agitated abrasive particulates through a wall of the container. The seal includes a first polymeric member around the shaft and in engagement with the wall of the container with the shaft rotating inside the first member. The first member is in engagement with a second polymeric member positioned around the shaft for rotation with the shaft and relative to the first member. A third compressible member is positioned around the shaft for rotation with the shaft and the second member. A retaining ring maintains the first, second and third members in compression between the retaining ring and the wall.