Abstract: Rotary sealing apparatus for sealing off between a relatively rotating shaft having an axis of rotation and mounting an impeller, and a relatively non-rotating wall through which the shaft extends, there being an annular seat on the wall, comprises:(a) a non-metallic seal ring extending about the shaft and engaging the seat to seal off between the seat and ring,(b) means located between the impeller and the seal ring to rotate the ring with the shaft, and(c) a non-metallic annular seal member located between the seal ring and the shaft to seal off therebetween.