1. Field of the Invention
The invention relates to a solid-bowl screw centrifuge having a centrifuge drum that is rotatable about a longitudinal axis, at least one outlet for discharging clarified material from the centrifuge drum, and an energy recovery device, arranged at the outlet for recovering energy from the clarified material flowing out.
2. Description of the Related Art
As is known, in order to rotate the centrifuge drum of a solid-bowl screw centrifuge, drive energy is necessary because, in order to introduce the material to be clarified or centrifuged, said material has to be given kinetic energy. Conversely, during emptying, the kinetic energy of the clarified material flowing out is converted into friction energy.
Attempts have been known to be made to use the kinetic energy of the material flowing out as far as possible in such a way that this energy contributes again to driving the rotational movement of the centrifuge drum. Known to this end are, inter alia, outlet ducts at outlet openings on the end side of the centrifuge drum, said outlet ducts diverting the stream of material in the tangential direction. The material that is then emerging not in the axial direction but in a tangential direction, supplies the centrifuge drum, on account of its centrifugal energy, with a pulse in the direction of rotation, said pulse driving the centrifuge drum in the direction of rotation. Such outlet ducts are known for example from WO 2012 013624 A1.
The invention is based on the object of creating a solid-bowl screw centrifuge in which the energy recovery is provided in a particularly cost-effective and at the same time particularly efficient manner on account of pulse feedback of the material flowing out.