Abstract: A jacketed centrifuge for exchanging material between liquids, usually a heavier liquid containing suspended solids and a lighter liquid, including a housing in which there is a drum mounted for rotation, and a conveyor worm mounted for rotation coaxially therewith. Inlet and outlet means are provided for introducing a relatively light liquid into the drum, as well as introducing the heavier liquid containing the solids suspended therein. Many of the elements of novelty are centered around the discharge means which are used for discharging solids from the drum. Basically, the drum is enlarged radially in the vicinity of the discharge means and is provided with various types of devices for discharging the solids into the discharge zone in a controlled manner.