Structure of a photobioreactor with conical ends, and method for manufacturing such a photobioreactor

Abstract

The invention relates to a photobioreactor structure comprising: - a transparent enclosure (E); - a lower end piece (I) and / or an upper end piece (S) configured to be connected to said enclosure (E); and - at least one connecting piece (RI, RS), characterized in that said lower end piece (I) and / or upper end piece (S) comprises: - a proximal portion (PP) having a connecting portion cooperating with said connecting piece (RI, RS) and the transparent enclosure (E); and - a distal portion (PD) comprising a distal end (AP), and in that the proximal portion (PP) comprises at least one bypass orifice (D1, D2, D3, D4) equipped with a bypass structure, and the distal end (AP) comprises at least one mouthpiece orifice (E1, S1) equipped with a mouthpiece structure. The invention also relates to a piece of furniture (M) and a method based on such a structure. Figure from the abstract: Fig. 2

Description

Title of the invention: Structure of a photobioreactor with conical ends, and method for manufacturing such a photobioreactor

[0001] The invention relates to the field of photobioreactor structures.

[0002] This type of bioreactor is used for the cultivation of photosynthetic microorganisms such as green algae or red algae. Therefore, it is necessary to provide either internal lighting for the bioreactor or external lighting with a generally transparent enclosure.

[0003] In the prior art, photobioreactor structures have been provided with a one-piece transparent cylindrical enclosure with a rounded bottom and a rounded top.

[0004] In use, it is required that the enclosure be easily opened, particularly for filling it with culture medium or for cleaning. Therefore, several bioreactor designs feature a removable lid that closes the upper end.

[0005] Furthermore, in use, it is advantageous in certain cases to provide for bypasses to implement recirculation of the medium, to carry out sampling within the bioreactor enclosure, or to inject fluids without completely opening the bioreactor.

[0006] This requires creating openings by drilling in the transparent enclosure, which implies a complex manufacturing process.

[0007] In addition, these derivations are generally fixed, and difficult to adapt to the different needs of several users.

[0008] Furthermore, the shape of bioreactor tanks requires improvement. Indeed, complex shapes and convolutions in a stirred medium can lead to decreased yields, as cells become trapped in the corners and convolutions.

[0009] A first objective of the present invention is to propose a photo-bioreactor structure that is easy and quick to manufacture and assemble.

[0010] A second objective is to propose a structure allowing several possible derivation configurations.

[0011] A third objective is to propose a tank shape that limits yield reductions and cell losses.

[0012] To achieve these objectives, the invention proposes a photobioreactor structure comprising: - a transparent enclosure of prismatic shape, in particular cylindrical, whose lower base and / or upper base are open; - a configured lower end piece and / or upper end piece to be connected to said lower and / or upper base; and - at least one connecting piece for connecting said lower and / or upper end piece to said lower and / or upper base, in a watertight manner, characterized in that said lower and / or upper end piece comprises: - a proximal portion of prismatic shape, in particular cylindrical, having a connecting part cooperating with said connecting piece and the transparent enclosure; and - a distal portion of pyramidal or preferably conical shape, the base of which is continuous with the proximal portion, and comprising a distal end, and in that the proximal portion comprises at least one bypass orifice equipped with a bypass structure, and the distal end comprises at least one mouthpiece orifice equipped with a mouthpiece structure.

[0013] Advantageously, the cylindrical enclosure connected at one or two ends facilitates assembly by means of a simple connection using the connecting piece. Furthermore, the majority of the tank is made in a cylindrical shape that is easy to manufacture. Moreover, a cylindrical shape facilitates observation of the cell culture in several directions in space, compared to a parallelepiped or cubic shape, for example.

[0014] In addition, the bypass and mouth structures can be selected or closed to have a bypass configuration specific to each user.

[0015] Furthermore, the prismatic or conical shape of the tip helps to limit cell loss in recesses or crevices. These cells can be drawn towards the apex and pushed towards the middle of the body, for example, in the case of the upper tip, or drawn in during the pull, for example, in the case of the lower tip.

[0016] According to one variant, the derivation structure is configured to receive at least one of the following: - gas injectors inserted into the end piece; - at least one probe inserted into the end piece; and - at least one liquid injector connected to the bypass structure

[0017] Gas injectors allow for agitation of the medium using a highly specific bubbling system. The probe allows for the detection of physicochemical characteristics or properties of the culture medium. The liquid injector provides a sterile circuit for injecting liquid into the medium without opening the reactor, thus limiting the risk of contamination.

[0018] According to one variant, the photobioreactor structure comprises: - the transparent enclosure which has a cylindrical shape, the lower and upper bases of which are open; - the lower end piece configured to be connected to said lower base; and - the upper end piece configured to be connected to said upper base; and - two connecting pieces to connect the end pieces to said bases in a watertight manner.

[0019] This allows for a reactor that is easy to produce in several series.

[0020] According to one variant, the lower end piece and / or the upper end piece is of a metallic type, in particular stainless steel.

[0021] This allows the orifices and bypass structures to be put in place by drilling and welding.

[0022] The invention further relates to a lower end piece for a photobioreactor structure according to the invention.

[0023] Another object of the invention relates to an upper end piece for a photobioreactor structure according to the invention.

[0024] The invention further relates to an assembly kit for a photobioreactor structure according to the invention, comprising: - the transparent enclosure; - the lower end piece and / or the upper end piece; and - said connecting piece.

[0025] This makes it easier to transport the photobioreactor.

[0026] The invention also relates to a piece of furniture for a photobioreactor structure according to the invention, comprising: - a speaker stand having a first circular receiving structure, which receives the speaker; and - an end support having a second circular receiving structure, receiving the lower end piece and / or the upper end piece.

[0027] This makes it possible to propose a simplified support system leaving most of the photobioreceptor visible for visual checks.

[0028] According to one variant, the furniture includes the photobioreactor structure according to the invention, and lighting means.

[0029] Another object of the invention relates to a method for assembling a photobioreactor structure according to the invention, comprising the following steps: - set up the transparent enclosure; - connect the lower end piece and / or the upper end piece to said lower and / or upper base of the enclosure, by means of said connecting piece.

[0030] The invention will be further detailed by describing non-limiting embodiments, and based on the accompanying figures illustrating preferred embodiments of the invention, in which: - [Fig.1] schematically illustrates a view in space of a photobioreactor structure according to a preferred embodiment of the invention; - [Fig.2] schematically illustrates a front view of a piece of furniture according to the invention comprising the photobioreactor structure of [Fig.1]; - [Fig.3] schematically illustrates a front view of a lower end piece of the photobioreactor structure of [Fig.1]; - [Fig.4] schematically illustrates a top view of the lower end piece of [Fig.3].

[0031] The invention relates firstly to the general structure of the photobioreactor. The structure comprises a cylindrical chamber E, the lower and / or upper base of which are open. The chamber E is used in a vertical position such that the main axis of the cylinder is vertical.

[0032] The structure further comprises a lower end piece I configured to be connected to said lower base by means of a lower connecting piece RL

[0033] The structure further includes also an upper end piece S configured to be connected to said upper base by means of an upper connecting piece RS.

[0034] The connection is made with an end piece I / S which can be slightly larger or smaller, or the same size (here diameter) as the corresponding part of the enclosure E. The connecting piece RI, RS is configured as appropriate for a leak-proof connection.

[0035] According to the invention, the lower end piece I comprises a proximal portion PP and a distal portion PD more clearly visible in [Fig.3].

[0036] The proximal portion PP is cylindrical in shape. It includes a connecting part cooperating with said connecting piece RI / RS and the transparent enclosure E to close the corresponding opening of the enclosure E in a hermetic manner.

[0037] The distal portion PD is conical in shape. The base of this cone is continuous with the cylindrical proximal portion PP. This cone has a distal end AP, shaped like an apex (best seen in [Fig.3]).

[0038] The lower end piece I can be metallic, for example stainless steel. Other materials can of course be considered within the scope of the invention, such as, in particular, plastic materials or structures produced by 3D printing.

[0039] Similarly, the upper end piece S comprises a proximal portion PP and a distal portion PD, preferably with the same characteristics as those detailed above.

[0040] Furthermore, according to the invention, said distal end AP comprises at least one mouth opening El, SI at the apex. The mouth opening can be equipped of a mouth structure. This refers in particular to the upper and lower distal AP ends.

[0041] Furthermore, the proximal portion PP includes at least one bypass port D1, D2, D3, D4 in a lateral position, or even several angularly spaced bypass ports. The bypass ports D1, D2, D3, D4 are equipped with bypass structures, more clearly visible in Figures 3 and 4. Pumps PI, P2 may also be provided.

[0042] In particular, the lower end piece I comprises a first set of several angularly spaced bypass orifices, configured to receive gas injectors G inserted into the end piece. In the illustrated embodiment, there are 4 gas injectors arranged around the photobioreactor structure.

[0043] Furthermore, the lower end piece I includes at least one bypass port configured to receive a probe, for example a pH probe, inserted into the end piece I.

[0044] Furthermore, a bypass D2, connected to a liquid injector via a sterile circuit, can be provided, allowing liquid to be injected into the medium without opening the reactor, thus limiting the risk of contamination. The liquid injector can be connected via a solenoid valve EV.

[0045] The invention also relates to a lower end piece I, and an upper end piece S as described above, as well as a corresponding mounting kit.

[0046] In use, the photobioreactor structure is housed in a specific cabinet M, for example a cupboard, equipped with lighting means L, such as light strips incorporating LEDs. The cabinet M may include panels and preferably a door. Thus, continuous illumination of the photobioreactor can be provided inside the cabinet M without obstructing the view outside the cabinet M.

[0047] The cabinet M includes a speaker support SE allowing the speaker E to be easily held in the cabinet M; and an end support SI allowing the end piece, here lower I, to be held in the cabinet M.

[0048] To this end, the speaker support SE comprises a first circular receiving structure, which receives the speaker E. The first receiving structure can be detached, for example into two semicircles, with the semicircular parts being secured by a hinge. Thus, this first receiving structure is opened to place the speaker E inside it before being closed.

[0049] Furthermore, the end support SI includes a second circular receiving structure, receiving the lower end piece I. The lower end piece I can be inserted there by the tip, and held there by the weight of the photobioreactor structure and the resistance of the second receiving structure.

[0050] This type of furniture M serves as a support for control devices, monitoring devices or others, to participate in the operation of the photobioreactor.

[0051] One can also consider a piece of furniture in the form of supports made of strands without panels or doors.

[0052] The assembly of the photobioreactor structure takes place in two main steps.

[0053] In a first step, the lower end piece I must be connected to said lower base of the enclosure E, by means of said lower connecting piece RI.

[0054] In a second step, the upper end piece S must be connected to the upper base of the enclosure E, by means of said upper connecting piece RS.

[0055] Once the photobioreactor structure is assembled, it only needs to be inserted into the cabinet M. For this purpose, the enclosure support SE can be opened to place the enclosure E inside. Then, the apex of the lower end piece I can be placed in the end support SI.

[0056] Regarding the arrangement, it can be adapted for a photobioreactor described previously, or for a bioreactor in the broadest sense.

[0057] Thus, the bioreactor comprises the enclosure E, a recirculation circuit RC, and a recirculation pump PI.

[0058] The enclosure E includes the lower end I having at least one outlet SI for liquids (namely here the mouth SI); and an upper end S having at least one inlet DI for liquids (namely here at the bypass orifice Dl).

[0059] In particular, said outlet Sla has a central position at the center of the apex of the lower end I, relative to the gas injectors G, which have a peripheral position. The gas injectors G are preferably gas diffusers, diffusing, for example, bubbles of less than 500 µm. This can be referred to as microbubbling in the context of this part of the invention.

[0060] In the illustrated variant, the mouthpiece orifice El serves to vent the gas injected into the chamber E, as well as the foam created by microbubbling. The mouthpiece orifice El also allows for overflow collection through the injection of medium via the bypass orifice D2 (continuous collection). The mouthpiece El overflows into a sterilizable container, and the gas is vented from this container through a filter.

[0061] Since the enclosure E is cylindrical, the gas injectors G are angularly spaced within the enclosure E around the central axis of the cylindrical shape. There are at least four gas injectors G. This allows for diffusion over the entire surface of a bioreactor, for example, with a diameter of 200 mm. Each injector diffuses over one-quarter of the enclosure's surface area of ​​revolution.

[0062] An individual injector device can be considered, which can be inserted into the container. The injector and / or the injector's gas inlet may or may not pass through a wall of the container. Such an injector device may have a shape of a ring or arc of a circle.

[0063] The RC recirculation circuit is connected to said input DI and said output SI. It allows for the recirculation of liquid in a pipe of small diameter relative to the enclosure E. This pipe measures, for example, 20mm in diameter.

[0064] The recirculation pump PI is connected to the outlet SI and to the lower part of the recirculation circuit RC.

[0065] The upper part of the RC recirculation circuit is connected to the DI inlet at the top of enclosure E.

[0066] According to the invention, the recirculation pump PI is configured to achieve a flow of liquid FL from said outlet SI to said inlet DI such that the flow of liquid FL in the enclosure E has an essentially vertical direction from top to bottom.

[0067] In addition, the gas injectors G are arranged at several points of the lower end I. Thus, they allow a vertical flow of gas FG from bottom to top.

[0068] The combination of the downward liquid flow FL and the upward gas flow FG allows for reverse circulation of gas and medium, homogenizing the culture and distribution of cells in the chamber E.

[0069] In the preferred embodiment, the recirculation circuit RC includes a transparent control window F. At this point, the wall is preferably completely transparent for a few centimeters. This window is preferably located at eye level so that it can be inspected without bending down. For example, it is in a range between 1.60 m and 1.75 m from the floor.

[0070] The invention also relates to the method of manufacturing a bioreactor as described above.

[0071] In this process, the recirculation pump PI is connected to the outlet SI of the enclosure E, as well as to the recirculation circuit RC.

[0072] Next, the RC recirculation circuit is connected to the DI input of enclosure E.

[0073] Pump P2 is a pump used to completely or partially drain the photobioreactor.

[0074] Regarding specifically the arrangement of the gas injectors G (diffusers), it can be adapted for a photobioreactor described above, or for a bioreactor in the broadest sense.

[0075] Thus, the bioreactor comprises the enclosure E which includes an enclosure wall, and a lower end I (here in the form of a separate end piece).

[0076] The lower end I comprises a lateral wall (here the proximal portion PP) and a bottom of a given shape (here the distal portion PD of conical shape).

[0077] The bioreactor further includes the gas injectors G arranged in the side wall PP of the lower end I.

[0078] According to the invention, the gas injectors are arranged therein so that their gas bubbles rise in the medium while being in contact with the enclosure wall of the enclosure E.

[0079] In order to cover the entire enclosure wall, the gas injectors G are arranged at several points on the side wall PP, here at points angularly spaced around the central axis of the cylindrical enclosure wall.

[0080] In the illustrated variant, the enclosure wall is arranged vertically. The gas bubbles are therefore preferably projected onto it.

[0081] The invention also relates to the method of manufacturing a bioreactor as described above.

[0082] In this method, the gas injectors G are placed in the side wall PP of the lower end I, so that their gas bubbles rise in the medium while being in contact with the enclosure wall of the enclosure E.

Claims

Claims

1. Photobioreactor structure comprising: - a transparent enclosure (E) of prismatic, in particular cylindrical, shape, the lower base and / or the upper base of which are open; - a lower end piece (I) and / or an upper end piece (S) configured to be connected to said lower and / or upper base; and - at least one connecting piece (RI, RS) for connecting said lower (I) and / or upper (S) end piece to said lower and / or upper base, in a sealed manner, characterized in that said lower (I) and / or upper (S) end piece comprises: - a proximal portion (PP) of prismatic, in particular cylindrical, shape, having a connecting part cooperating with said connecting piece (RI, RS) and the transparent enclosure (E);and - a distal portion (PD) of pyramidal or preferably conical shape, the base of which is continuous with the proximal portion (PP), and comprising a distal end (AP), and in that the proximal portion (PP) comprises at least one bypass orifice (Dl, D2, D3, D4) equipped with a bypass structure, and the distal end (AP) comprises at least one mouthpiece orifice (El, SI) equipped with a mouthpiece structure.;

2. Photobioreactor structure according to the preceding claim, characterized in that the bypass structure is configured to receive at least one of: - gas injectors (G) inserted into the end piece; - at least one probe (S) inserted into the end piece (I); and - at least one liquid injector (RI) connected to the bypass structure.

3. Photobioreactor structure according to one of the preceding claims, comprising: - the transparent enclosure (E) which has a cylindrical shape, the lower and upper bases of which are open; - the lower end piece (I) configured to be connected to said lower base; and - the upper end piece (S) configured to be connected to said upper base; and - two connecting pieces (RI, RS) for connecting the end pieces (I, S) to said bases in a watertight manner.

4. Photobioreactor structure according to one of the preceding claims, characterized in that the lower end piece (I) and / or the upper end piece (S) is of metallic type, in particular stainless steel.

5. Lower end piece (I) for a photobioreactor structure according to one of the preceding claims.

6. Upper end piece (S) for a photobioreactor structure according to one of claims 1 to 4.

7. Kit for mounting a photobioreactor structure according to one of claims 1 to 4, comprising: - the transparent enclosure (E); - the lower end piece (I) and / or the upper end piece (S); and - said connecting piece.

8. Furniture (M) for a photobioreactor structure according to one of claims 1 to 4, comprising: - an enclosure support (SE) having a first circular receiving structure, receiving the enclosure (E); and - an end support (SI) having a second circular receiving structure, receiving the lower end piece (I) and / or the upper end piece.

9. Furniture (M) according to the preceding claim, comprising the photobioreactor structure according to one of claims 1 to 4, and lighting means (L).

10. Method for assembling a photobioreactor structure according to one of claims 1 to 4, comprising the following steps: - placing the transparent enclosure (E); - connecting the lower end piece (I) and / or the upper end piece (S) to said lower and / or upper base of the enclosure (E), by means of said connecting piece (RI, RS).

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