One-way separator for retaining and recirculating cells

1. A solids separator for retaining and recirculating solids from a reactor mixture, comprising a flow-bearing sterilizable plastic bag or plastic bottle and, within the plastic bag or plastic bottle:

in the upper region, one or more passages/internals for withdrawing from a harvest stream collection region a harvest stream that is separated from the solids,

in the upper segment of a central region, a separation region having a separation area, which, during operation, is inclined at an angle of 0° to 80° to the horizontal,

in the lower segment of the central region, one or more passages or internals for a uniform horizontal flow distribution of the reactor mixture over an introduction surface, wherein the separation area is situated above the introduction surface,

in the lower region a solids collection region that is tapered at the bottom for collecting the solids using gravity.

2. The solids separator of claim 1 , wherein solids collection region has one or more passage or internals for withdrawing the solids.

3. The solids separator of claim 2 , wherein the plastic bag or plastic bottle has a rectangular cross section, wherein the downwardly tapered solids collection region ends in a neck which is closed with a cover or stopper, wherein the cover or stopper has all passages.

4. The solids separator of claim 1 , wherein the solids collection region is tapered downwards conically or pyramidally.

5. The solids separator of claim 1 , which comprises at least one single-use sensor in the interior.

6. The solids separator of claim 1 , wherein the separation region consists of a multiplicity of adjacently arranged channels in a lamellae pack and the separation area during operation is inclined at an angle to the horizontal of 30° to 80°.

7. The solids separator of claim 6 , wherein the lamellae pack consists of a plurality of ridgeplates stacked one above the other which form the channels of the lamellae pack.

8. The solids separator of claim 7 , wherein the ratio of ridge height to channel width hs/d is 0.01≦hs/d ≦5 with the restriction.

9. The solids separator of claim 6 , wherein the channels have a channel length L of 30% to 95% of a length LK of the plastic bag or plastic bottle.

10. The solids separator of claim 1 , wherein the plastic bag is polyhedral or conical and wherein the plastic bag, during operation, is placed such that the solids collection region which is tapered at the bottom is formed by the walls of the plastic bag and the apex or corner of the polyhedron or of the cone.

11. The solids separator of claim 10 , wherein the plastic bag is a disphenoid, a regular pyramid, an octahedron or a cube.

12. The solids separator of claim 1 , comprising a container for receiving the plastic bag, wherein the container comprises at least:

(a) an interior for receiving the plastic bag, wherein the interior is adapted to the shape of the plastic bag by means of walls which are adapted to the shape of the plastic bag and enclose the interior and delimit it from the exterior, and (b) an opening for introducing the plastic bag from the top into the container.

13. The solids separator of claim 1 , wherein the separation area does not comprise plates.

14. A bioreactor system comprising a bioreactor connected to a solids separator as claimed in claim 1 .

15. A method for retaining and recirculating solids in a flow-bearing vessel of the solids separator of claim 1 , comprising

supplying solids-containing medium continuously or batchwise to the vessel, and

removing solids-free medium from the vessel,

wherein the vessel is the flow-bearing sterilizable plastic bag or plastic bottle which, in the lower region, comprises faces set at an incline, favorably the solids collection region, which is tapered conically at the bottom for collecting the solids with the aid of gravity,

wherein the solids comprise cells.