Abstract: An apparatus for mixing a substance, the apparatus including a container, a tubular conduit axially disposed in a cavity of the container defining an inner tubular channel and an outer annular channel within the container, a conduit for admitting a substance into the cavity, a rotary device for circulating the substance in the cavity, an extraction conduit, a carrier shaft of the rotary device being guided in rotation by a bearing or other rotary guiding device proximate an end of the container at which the substance to be mixed is passed from the tubular channels into the annular channel.