MIXING DEVICE HAVING A FLOW BREAKER

Abstract

A mixing device (10) comprises a flexible container (14), at least one stirring element (22) and at least one baffle (24). The baffle (24) is formed on the inside on a circumferential side wall (16) of the flexible container (14) and has a free end protruding into the interior of the container (14). A main application of the mixing device (10) is considered to be the use as disposable bioreactor.

Claims

1. A mixing device comprising a flexible container, at least one stirring element and at least one baffle, characterized in that the baffle is formed on the inside on a circumferential side wall of the flexible container and has a free end protruding into the interior of the container.

2. The mixing device according to claim 1, characterized in that the baffle has a shell which is formed of a flexible film material.

3. The mixing device according to claim 2, characterized in that the flexible container and the shell are formed of the same material.

4. The mixing device according to claim 2, characterized in that the shell comprises a double-layered portion.

5. The mixing device according to claim 4, characterized in that the double-layered portion of the shell is divided into two receiving portions by means of a vertical partition, wherein the vertical partition protrudes into the interior of the container as a free end of the baffle.

6. The mixing device according to claim 2, characterized in that at least one dimensionally stabilizing plate is arranged in the shell.

7. The mixing device according to claim 2, characterized in that the shell comprises several partitioned compartments, in each of which a plate is accommodated.

8. The mixing device according to claim 2, characterized in that the shell or the entire baffle is sealed in a gas-tight way and includes at least one fluid port.

9. The mixing device according to claim 8, characterized in that the shell or the entire baffle is filled with a tempered fluid.

10. The mixing device according to claim 1, characterized in that the baffle comprises two tabs for fixing the baffle at the circumferential side wall of the flexible container.

11. The mixing device according to claim 10, characterized in that the tabs are fixed at the circumferential side wall by welding, gluing or a comparable fixing method.

12. The mixing device according to claim 10, characterized in that the tabs extend on opposite sides of a base portion facing the shell.

13. The mixing device according to claim 10, characterized in that the flexible container and the tabs are formed of the same material.

14. The mixing device according to claim 1, characterized in that between the inside of the flexible container and the baffle several spacers are arranged.

15. The mixing device according to claim 14, characterized in that the spacers are spaced from each other vertically and/or horizontally.

16. The mixing device according to claim 1, characterized in that the baffle has no through openings.

17. The mixing device according to claim 4, characterized in that at least one dimensionally stabilizing plate is arranged in the shell.

18. The mixing device according to claim 17, characterized in that the shell includes several partitioned compartments, in each of which a plate is accommodated.

19. The mixing device according to claim 5, characterized in that at least one dimensionally stabilizing plate is arranged in the shell.

20. The mixing device according to claim 19, characterized in that the shell includes several partitioned compartments, in each of which a plate is accommodated.

Description

[0035] Further features and advantages of the invention can be taken from the following description and from the attached drawings, to which reference is made. In the drawings:

[0036] FIG. 1 shows a lateral sectional view of a mixing device with baffles according to the invention;

[0037] FIG. 2 shows a top view of a segment of a mixing device according to the invention;

[0038] FIG. 3 shows a perspective view of a segment of a mixing device according to the invention; and

[0039] FIG. 4 shows a lateral sectional view of a mixing device with a baffle according to the invention in a design variant with spacers.

[0040] FIG. 1 shows a mixing device 10 which is provided for use as bioreactor. The mixing device comprises a substantially cylindrical support container 12 open at the top, into which a container 14 with flexible walls 16, 18, 20 is inserted. The flexible container 14 is arranged such that its walls, in particular the circumferential side wall 16 and the bottom wall 18, rest against the opposed inner walls of the support container 12 as far as possible with regard to an optimum support and an optimum heat transfer.

[0041] The flexible container 14 here is a culture vessel in the form of a pre-sterilized disposable bag which is formed of a film. Into the flexible container 14 two stirring elements 22 are integrated, which are parts of a stirrer of the mixing device 10. There can of course also be provided another number of stirring elements 22.

[0042] On the inside of the circumferential side wall 16 of the flexible container 14 several baffles 24 are mounted, which extend into the interior of the container. The construction and installation of the baffles 24 will be explained in detail below with reference to the exemplary representation of a baffle 24 in FIGS. 2 and 3.

[0043] The baffle 24 for the most part is formed of a film which preferably consists of the same material as the flexible container 14. From a base portion 26 two tabs 28 extend on opposite sides, by means of which the baffle 24 is fixed at the side wall 16 of the flexible container 14, in particular by welding.

[0044] Between the tabs a shell 30 furthermore extends in the form of a double-layered film portion which is welded to the tabs 28 or connected with the same in some other way or integrally formed with the same. The double-layered portion in turn is divided into two receiving portions 34, 36 by a middle vertical partition 32, for example a welding seam. In the position of use of the mixing device 10 as seen from above (see FIG. 2) the two receiving portions 34, 36 and the base portion 26 together form a triangle whose tip, represented by the vertical partition 32, protrudes into the interior of the container as free end of the baffle 24.

[0045] Into the receiving portions 34, 36 rigid plates 38 are inserted. The receiving portions 34, 36 are divided by a plurality of substantially horizontal partitions 40, for example welding seams, such that several compartments are formed. In each of these compartments a plate 38 is accommodated.

[0046] The baffles 24 alone can be spread out flat or be folded together for transport in a space-saving way, even if the plates 38 already are inserted. The assembly of the baffles 24 at the flexible container 14 then can be effected at the site of use, in that the prefabricated baffles 24 are mounted on the flexible container 14 at the desired points.

[0047] In pre-sterilized disposable containers on the other hand it is provided to install the baffles 24 already before shipment of the mixing device 10, in particular when a particular configuration frequently is desired, for example with four identical baffles uniformly distributed around the inner circumference of the flexible container 14. In this case, the flexible container 14 still can be folded together to form a relatively compact package.

[0048] In the following some design variants of the mixing device 10 will be described with reference to the baffles 24. It generally applies that not all features of a particular design variant necessarily must be realized. On the other hand, features of different design variants also can be combined with each other.

[0049] To bring a baffle 24 into its final shape, the same can be filled with a liquid or a gas (hereinafter: fluid) alternatively or in addition to the plates 38. For this purpose, as indicated in FIG. 1, the baffle 24 is equipped with at least one fluid port 42 which via a hose line 44 can be connected with a fluid port 46 arranged in the ceiling wall 20 of the flexible container 14. Otherwise, the baffle 24 is sealed in a gas-tight way.

[0050] As far as necessary, the distribution of the supplied fluid within the baffles 24 is effected via further hose lines or other flow connections between the compartments in which the plates 38 are accommodated. Just as well, however, separate portions in the baffles 24 or the entire baffles 24 also can be provided to take up the fluid. As mentioned already, the reinforcing plates 38 also can be omitted partly or entirely in the case of a fluid stabilization, as is indicated in the right-hand half of FIG. 1.

[0051] In general, the pressure which is introduced by the fluid must not endanger the stability of the baffles 24, in particular of the partitions 32, 40 (welding seams) —as far as present—and the fixing points. In practice, the maximum admissible pressure largely depends on the used film material.

[0052] Alternatively or in addition, the supplied fluid can be utilized for tempering the flexible container 14 or the liquid present therein. In this case, an additional fluid port is provided at the shell 30 or at another wall delimiting the interior space of the baffle 24, through which the fluid can again be guided out of the baffle 24 at another point, so that a continuous flow of tempered fluid through the baffle 24 is possible. Of course, separate hose lines or the like also can be provided for this purpose.

[0053] Since the fluid flowing into or through the baffle 24 does not get in contact with the sensitive content of the flexible container 14, a non-sterile fluid (e.g. ambient air or normal water) can be used for the above-mentioned purposes. Alternatively, a filter also can be connected before the supplied fluid, in order to guide the same into or through the baffles in a sterile condition.

[0054] A further design variant is shown in FIG. 4. Here, several spacers 48 are arranged between the side wall 16 of the flexible container 14 and a baffle 24. In this arrangement, the liquid in the flexible container 14—as seen vertically—can flow through between the spacers 48. In conjunction with the impenetrable baffles 24 further fluidizations can be enforced and intermixing thereby can be promoted. The radial distance of the baffles 24 from the side wall 16 of the flexible container 14, which is achieved by means of the spacers 48, lies in a range between 0 and about 200 mm in dependence on the container size.

[0055] Apart from the baffles 24 on the side wall 16 of the flexible container 14, baffles in principle can also be arranged on the bottom wall 18 and/or on the ceiling wall 20.

[0056] As already mentioned above, the invention is not limited to disposable bioreactors, but can also be used in other bag-based mixing devices.

LIST OF REFERENCE NUMERALS

[0057] 10 mixing device [0058] 12 support container [0059] 14 flexible container [0060] 16 side wall [0061] 18 bottom wall [0062] 20 ceiling wall [0063] 22 stirring element [0064] 24 baffle [0065] 26 base portion [0066] 28 tab [0067] 30 shell [0068] 32 vertical partition [0069] 34 receiving portion [0070] 36 receiving portion [0071] 38 plate [0072] 40 horizontal partition [0073] 42 fluid port [0074] 44 hose line [0075] 46 fluid port [0076] 48 spacer