PHOTOBIOREACTOR, IN PARTICULAR FOR THE PRODUCTION OF MICRO-ORGANISMS SUCH AS MICROALGAE

Abstract

A photobioreactor is particularly suited for producing micro-organisms such as microalgae. The photobioreactor is a closed reactor with reactor vessels which have an open top that is closed by a top wall of the photobioreactor and in which a nutrient medium can be held. At least some of the reactor vessels are individual vessels. Adjacent reactor vessels form a gap between a front wall and a rear wall, the gap being closed at the top side by an overflow wall region and having a vessel overflow opening between the adjacent reactor vessels. A lighting element is held in the gap. Each of the reactor vessels has a partition which divides the reactor vessel into a front reactor chamber and a rear reactor chamber. At least one partition through-flow opening between the front and rear reactor chambers is formed in the partition close to the bottom wall.

Claims

1-33. (canceled)

34. A photobioreactor being a closed reactor, the photobioreactor comprising: a plurality of upwardly open reactor vessels configured for accommodating a nutrient medium; a top wall of the photobioreactor being a one-piece or a multi-piece top wall for closing the reactor vessels; at least some of said reactor vessels being formed as individual vessels which, in cross section, have a U-shape with a front wall extending in vertical axis direction, a back wall, spaced apart from said front wall in a longitudinal direction and also extending in the vertical axis direction, and a bottom wall connecting said front and back walls to one another at a bottom of the vessel; said reactor vessels that are formed as individual vessels being arranged one after another in the longitudinal direction in such a way that a front reactor vessel has an at least regionally light-transmissive back wall adjacent to an at least regionally light-transmissive front wall of a rear reactor vessel, with a formation of a gap therebetween, wherein free end regions of said front and back walls adjacent one another have a common flow-over wall region which closes said gap from above, and which is formed with at least one vessel flow-over opening between said adjacent reactor vessels; said flow-over wall region extending up to said top wall or to at least one piece of said multi-piece top wall and being adjacent thereto; at least one lighting element disposed in said gap between mutually adjacent reactor vessels, said at least one lighting element being formed to emit light through a respectively assigned, at least regionally light-transmissive front wall and/or back wall into one of said mutually adjacent reactor vessels or into both said mutually adjacent reactor vessels; a partition wall in each of said reactor vessels that are formed as individual vessels, said partition wall, proceeding from said bottom wall, extending upward in the vertical axis direction to said top wall and being adjacent thereto, with said partition wall dividing said reactor vessel into a front reactor chamber and a rear reactor chamber; and said partition wall, in a near-bottom-wall region of said partition wall that is adjacent and/or connected to said bottom wall, being formed with at least one partition-wall flow-through opening between said front and rear reactor chambers.

35. The photobioreactor according to claim 34, wherein: said bottom wall, said partition wall, said front wall, said back wall, and said flow-over wall region of said reactor vessel extend between two side walls opposite in a transverse direction and are adjacent thereto; and each of said side walls extends up to said top wall and are adjacent thereto.

36. The photobioreactor according to claim 35, wherein: said bottom wall of said reactor vessel is arched, with a vertex of a curvature being situated at a lowest point of said reactor vessel in the vertical axis direction; and opposite side walls extend downward, as seen in the vertical axis direction, at least as far as the vertex of said bottom wall and form a ground contact area.

37. The photobioreactor according to claim 35, wherein each of said individual reactor vessels has two separate opposite side walls.

38. The photobioreactor according to claim 34, wherein at least one of said reactor vessel or said top wall is altogether light-transmissive and composed of a light-transmissive glass material or plastics material.

39. The photobioreactor according to claim 34, wherein at least one of said front wall, said back wall, said partition wall, said flow-over wall region, or said side walls is rectangular and/or plate-shaped.

40. The photobioreactor according to claim 34, wherein said one-piece or multi-piece flow-over wall region is integrally formed with at least one of the free end region of said front wall or the free end region of said back wall of said reactor vessel.

41. The photobioreactor according to claim 40, wherein: said flow-over wall region is integrally formed with the free end region of said front wall or with the free end region of said back wall of the reactor vessel and a free end region of said back wall or said front wall of a directly adjacent reactor vessel is also connected to said flow-over wall region to form a common flow-over wall region; or said flow-over wall region is a multi-piece wall region and a first front-wall-side flow-over wall region element is integrally formed with the free end region of said front wall of said reactor vessel and a second back-wall-side flow-over wall region element is integrally formed with the free end region of said back wall of said reactor vessel, wherein a front-wall-side flow-over wall region element and a back-wall-side flow-over wall region element are connectable to one another to form the common flow-over wall region.

42. The photobioreactor according to claim 34, wherein said flow-over wall region is a one-piece or multi-piece flow-over wall region formed by a separate component which is connectable to at least one of said front wall or said back wall of two mutually adjacent said reactor vessels.

43. The photobioreactor according to claim 34, wherein said flow-over wall region has a peripherally encircling frame and said vessel flow-over opening surrounded by said frame, with a lower frame subregion in the vertical axis direction forming a connection region for the free end region of said front wall and/or said back wall of the respectively assigned said reactor vessels and/or with an upper frame subregion in the vertical axis direction being adjacent said top wall.

44. The photobioreactor according to claim 34, wherein said flow-over wall region has at least one flow guide element protruding into said at least one vessel flow-over opening, and/or wherein a plurality of vessel flow-over openings are formed next to one another in the transverse direction.

45. The photobioreactor according to claim 44, further comprising at least one connecting web running between frame parts in the vertical axis direction and between frame parts opposite in the vertical axis direction, forming a flow guide element, to form a plurality of vessel flow-over openings.

46. The photobioreactor according to claim 34, wherein said at least one lighting element comprises one or more lighting bodies, and said lighting bodies have beam angles and light cones which, in a fitted state of said at least one lighting element are fixed or adjustable.

47. The photobioreactor according to claim 34, wherein said at least one lighting element is arranged in said gap between said mutually adjacent reactor vessels in such a way that, in said at least one reactor chamber of said mutually adjacent reactor vessels that is illuminated by said at least one lighting element, regions are illuminated with differing brightness when said at least one lighting element is energized.

48. The photobioreactor according to claim 34, wherein said at least one lighting element is one of a plurality of lighting elements accommodated in said gap between said mutually adjacent reactor vessels and spaced apart from one another in the vertical axis direction and/or in the transverse direction, and wherein a plurality of rows of lighting elements extending in the transverse direction are disposed with a spacing distance from one another.

49. The photobioreactor according to claim 48, wherein said lighting elements are evenly spaced apart from one another in the vertical axis direction and said rows of lighting elements extend in the transverse direction and are formed by a plurality of lighting elements spaced apart from one another and/or by light strips.

50. The photobioreactor according to claim 34, further comprising a stiffening element disposed in said gap between said mutually adjacent reactor vessels in a transition region from said front wall and/or said back wall to said bottom wall, said stiffening element extending over a specified length in the transverse direction between opposite side walls.

51. The photobioreactor according to claim 34, wherein said partition wall, in a wall region near said bottom wall, has a peripherally encircling frame region with a partition-wall flow-through opening surrounded by said frame region, and wherein a lower frame subregion in the vertical axis direction is adjacent to said bottom wall.

52. The photobioreactor according to claim 51, wherein said partition wall has at least one flow guide element protruding into said partition-wall flow-through opening and/or a plurality of partition-wall flow-through openings lying next to one another in the transverse direction.

53. The photobioreactor according to claim 51, further comprising at least one connecting web running between frame parts or at least one connecting web running in the vertical axis direction and between frame parts opposite in the vertical axis direction and forming a flow guide element defining a plurality of partition-wall flow-through openings.

54. The photobioreactor according to claim 34, wherein at least one of said reactor vessels is formed with at least one feed nozzle for introducing a medium into said reactor vessel from outside said reactor vessel.

55. The photobioreactor according to claim 54, wherein said at least one feed nozzle is arranged in a near-bottom-wall region of said reactor vessel, in a region of said rear reactor chamber on said bottom wall and/or on said back wall.

56. The photobioreactor according to claim 54, wherein a mouth opening of said at least one feed nozzle is oriented in a flow direction of the medium.

57. The photobioreactor according to claim 34, further comprising an inlet for a nutrient medium formed in a forwardmost reactor vessel in the longitudinal direction or flow-through direction, in at least one of a top wall, a front wall, or a side wall of the forwardmost reactor vessel.

58. The photobioreactor according to claim 57, wherein said inlet is coupled to a conveying device that functions as a conveying device and as a circulation device for the nutrient medium in the photobioreactor, by way of which a portion of the nutrient medium that is extracted from a rear region of the photobioreactor in the longitudinal direction or flow-through direction, is feedable to the forwardmost reactor vessel.

59. The photobioreactor according to claim 58, wherein said conveying device is formed by an air-lift arrangement in which a working medium, being air, CO.sub.2-enriched air, or filtered air, is introduced into a nutrient medium line guided toward said inlet, wherein the working medium conveys the nutrient medium in the direction of said inlet.

60. The photobioreactor according to claim 34, wherein an outlet for the nutrient medium is formed in a rearmost reactor vessel in the longitudinal direction or flow-through direction, in at least one of a top wall, a back wall, or a side wall of the rearmost reactor vessel, the outlet enabling a discharge of a nutrient medium from a rear reactor chamber of the rearmost reactor vessel.

61. The photobioreactor according to claim 60, wherein said outlet is a drain, an overflow drain, or is coupled to an extraction device, for extracting the nutrient medium from the rearmost reactor vessel in dependence on a density of the microorganisms produced in the photobioreactor.

62. The photobioreactor according to claim 61, further comprising a continuous belt filter disposed downstream of said outlet, wherein a continuous filter cloth is circulated in said continuous belt filter between a filtering section and a section in which filtered product is removed from the filter cloth.

63. The photobioreactor according to claim 34, further comprising at least one ventilation device in said top wall for extracting a gas that accumulates between said top wall and the nutrient medium from an interior of the photobioreactor, with a respective top-wall-side ventilation device being assigned to each reactor vessel.

64. The photobioreactor according to claim 34, wherein: all of said reactor vessels have an identical U-shaped basic structure with a front wall and a back wall of substantially identical height, with said front wall and said back wall being disposed with a gap space relative to said top wall and being overtopped by said partition wall which extends up to said top wall and adjoins said top wall; said gap space, in a region between two mutually adjacent reactor vessels, is bridged by said flow-over wall region, which extends up to said top wall and adjoins said top wall; said front wall of a forwardmost reactor vessel in the longitudinal direction or flow-through direction has a first wall-shaped and/or plate-shaped bridging element which extends up to said top wall and adjoins said top wall; said back wall of a rearmost reactor vessel in the longitudinal direction or flow-through direction has a second wall-shaped and/or plate-shaped bridging element which extends up to the top wall and adjoins said top wall; and said first and second wall-shaped and/or plate-shaped bridging elements, all of said front walls, partition walls, and back walls, and said at least one flow-over wall region extend in the transverse direction between said side walls, and said side walls likewise extend up to said top wall, to thereby form a closed reactor when said top wall is mounted.

65. A reactor vessel for a photobioreactor, the reactor vessel comprising: an upwardly open vessel which, viewed in cross section, has a U-shape with a rectangular and/or plate-shaped front wall extending in a vertical axis direction, a rectangular and/or plate-shaped back wall spaced apart therefrom in the longitudinal direction and likewise extending in the vertical axis direction, and a bottom wall connecting said front wall and said back wall to one another; a partition wall in said vessel which extends upward in the vertical axis direction proceeding from said bottom wall and which divides the reactor vessel into a front reactor chamber and a rear reactor chamber, relative to the longitudinal direction; and said partition wall, in a near-bottom-wall region of said partition wall that is adjacent and/or connected to said bottom wall, is formed with at least one partition-wall flow-through opening between said front and rear reactor chambers.

66. A method for producing microorganisms in a photobioreactor, the method comprising: providing a closed reactor formed with a plurality of upwardly open reactor vessels which are closed by a one-piece or multi-piece top wall and in which a nutrient medium is to be accommodated; wherein at least some of the reactor vessels are formed as individual vessels which, in cross section, have a U-shape with a front wall extending in a vertical axis direction, a back wall spaced apart therefrom in a longitudinal direction and likewise extending in the vertical axis direction, and a bottom wall connecting the front and back walls to one another; wherein the reactor vessels of the photobioreactor that are designed as individual vessels are arranged one after another in the longitudinal direction in such a way that a front reactor vessel, as seen in the longitudinal direction, having an at least regionally translucent back wall is adjacent an at least regionally translucent front wall of a rear reactor vessel, as seen in the longitudinal direction, with formation of gap, wherein free end regions of the front and back walls adjacent to one another with formation of the gap have a common flow-over wall region which closes the gap from above and which has at least one vessel flow-over opening between the adjacent reactor vessels; wherein the flow-over wall region extends up to and adjoins the top wall in a gas-tight and liquid-tight manner and/or is connected thereto; accommodating at least one lighting element in the gap between mutually adjacent reactor vessels, and radiating light through the respectively assigned, at least regionally translucent front wall and/or back wall into one of the two adjacent reactor vessels or into the two adjacent reactor vessels; wherein each of the reactor vessels of the photobioreactor that are designed as individual vessels contain a partition wall which proceeds from the bottom wall, extends upward in the vertical axis direction to the top wall to adjoin the top wall in a gas-tight and liquid-tight manner, wherein the partition wall divides the reactor vessel into a front reactor chamber and a rear reactor chamber along the longitudinal direction; and providing in the partition wall, in a near-bottom-wall region of the partition wall that is adjacent and/or connected to the bottom wall, at least one partition-wall flow-through opening between the front reactor chamber and the rear reactor chamber, and enabling a nutrient medium accommodated in the front reactor chamber of a front reactor vessel to flow through the at least one partition-wall flow-through opening into the rear reactor chamber of the front reactor vessel and to further flow through the at least one vessel flow-over opening from the rear reactor chamber of the front reactor vessel into a front reactor chamber of a rear reactor vessel.

67. The method according to claim 66, which comprises providing the photobioreactor according to claim 34 and producing microalgae in the reactor vessels of the photobioreactor.

Description

[0082] In the figures:

[0083] FIG. 1 shows a schematic front view of an exemplary photobioreactor according to the invention with a view of the forwardmost reactor vessel in the direction of the arrow Z in FIG. 2a,

[0084] FIG. 2a shows a schematic longitudinal cross section along the line A-A of FIG. 1,

[0085] FIG. 2b shows a schematic perspective sectional view of the photobioreactor from FIG. 2a with features partially omitted,

[0086] FIG. 3a shows a schematic exemplary embodiment of a flow-over wall region formed by a separate component,

[0087] FIG. 3b shows a schematic sectional view along the line C-C of FIG. 3a,

[0088] FIG. 3c shows a schematic view of a further alternative embodiment of the flow-over wall region,

[0089] FIG. 4a shows a schematic detailed view of a bridging element forming an outlet,

[0090] FIG. 4b shows a section along the line D—D of FIG. 4a,

[0091] FIG. 5 schematically shows a front view of an individual reactor vessel,

[0092] FIG. 6 shows a sectional view along the line B-B of FIG. 5,

[0093] FIG. 7 shows a perspective view of the individual reactor vessel of FIGS. 5 and 6 with side walls,

[0094] FIG. 8a shows an enlarged detailed view of a partition wall in a top view,

[0095] FIG. 8b shows an alternative embodiment of the partition-wall frame region of FIG. 8a,

[0096] FIG. 9a shows a schematic view of an alternative embodiment of a flow-over wall region which is integral with the free end region of the back wall of a reactor vessel,

[0097] FIG. 9b shows a schematic view of an alternative embodiment of a flow-over wall region which is integral with the free end region of a front wall of a reactor vessel, and

[0098] FIG. 10 shows a schematic view of a further alternative embodiment of a two-piece flow-over wall region, the flow-over wall region elements of which are integral with the free end region of the back wall and with the free end region of the front wall of a reactor vessel.

[0099] Looked at together, FIGS. 1, 2a and 2b show an exemplary embodiment of a photobioreactor 1 according to the invention for production of microorganisms, especially production of microalgae. As is evident especially from FIGS. 2a and 2b, said photobioreactor 1 comprises a plurality of reactor vessels 2 which are designed as an individual vessel and in which a nutrient medium is accommodated.

[0100] As is evident especially from FIGS. 5, 6, 7 and 8 when looked at together, the individual reactor vessels 2 all preferably have an essentially identical U-shaped basic structure in which the reactor vessels 2 are each designed as an upwardly open vessel and have a front wall 3 extending in the vertical axis direction z and a back wall 4 spaced apart therefrom in the longitudinal direction x and likewise extending in the vertical axis direction z. The front wall 3 and the back wall 4 are both connected to one another at the bottom by a bottom wall 5.

[0101] Here, both the front wall 3 and the back wall 4 are plate-shaped and rectangular by way of example, whereas the bottom wall 5 is arched here by way of example.

[0102] As is evident especially from FIG. 6, the front wall 3 and the back wall 4 have a substantially identical height and are overtopped in the vertical axis direction z by a partition wall 6 arranged centrally in the reactor vessel 2 here by way of example. Said partition wall 6 is also plate-shaped and rectangular here by way of example, which is evident especially also from FIG. 8a, which shows an individual depiction of the partition wall 6.

[0103] In the fitted state (see, for example, FIG. 2a), the partition wall 6 extends upward in the vertical axis direction z, proceeding from the bottom wall 5, to a top wall 7, which is merely drawn in here with dashed lines for reasons of clarity and is, for example, likewise plate-shaped and rectangular. By means of its upper free end region in the vertical axis direction, the partition wall 6 is adjacent to the top wall 7, specifically preferably in a gas- and/or liquid-tight manner. Optionally, the partition wall 6 can also be connected to the top wall 7, specifically especially detachably connected thereto. The top wall 7 is depicted here as one piece, but may also be of multi-piece design.

[0104] As is evident especially from FIGS. 2a, 2b and 6, the partition wall 6 divides the reactor vessel into a front reactor chamber 8 and a rear reactor chamber 9, based on the longitudinal direction x.

[0105] As is evident especially from FIG. 8a, what are formed in the partition wall 6, in the near-bottom-wall region of the partition wall that is adjacent and/or connected to the bottom wall 5, are a plurality of partition-wall flow-through openings 10 which enable the nutrient medium to flow over from the front reactor chamber 8 into the rear reactor chamber 9.

[0106] The partition wall 6 as well as the front wall 3 and the back wall 4 extend, as seen in the transverse direction y, between two side walls 11 which are opposite in the transverse direction y and are likewise rectangular and plate-shaped here merely by way of example and which, as is evident especially from FIGS. 2a, 2b and 7, each extend up to the top wall 7 and are adjacent thereto, especially adjacent thereto in a gas- and/or liquid-tight manner and/or optionally even connected thereto. What was last mentioned also applies of course to the adjacency of the front wall 3, the partition wall 6 and the back wall 4 to the side walls 11.

[0107] At this point, it should be noted that the top wall 7 is preferably designed as a removable top wall, and so in this case either no connection may be provided or a detachable connection must be provided between the top wall 7 and the walls or wall regions adjacent thereto.

[0108] As is further evident from FIGS. 2a and 7 in particular, the vertex of the curvature of the bottom wall 5 of the reactor vessel is situated at the lowest point of the reactor vessel 2 as seen in the vertical axis direction z, and so the opposite side walls 11 extend downward, as seen in the vertical axis direction z, at least as far as the vertex of said bottom wall 5 and hence form a ground contact area.

[0109] In the exemplary embodiment of FIGS. 2a and 7 that is shown, each individual reactor vessel 2 has two separate opposite side walls 11. However, FIG. 2b depicts an alternative variant in which two opposite large-area side walls 11 both form the side walls for a plurality of reactor vessels 2 or, in the case of FIG. 2b, for all the reactor vessels 2.

[0110] Both the individual reactor vessels 2 and the top wall 7 are preferably altogether light-transmissive, for example composed of a light-transmissive glass material or plastics material.

[0111] As is further evident from FIG. 6 when looked at together with FIGS. 2a and 2b, all the reactor vessels 2 have an identical U-shaped basic structure with a front wall 3 and back wall 4 of identical height, both of which have a gap space in relation to the top wall 7 and both of which are overtopped by the partition wall 6 which extends up to the top wall 7.

[0112] In order to bridge the gap space in relation to the top wall 7, the photobioreactor 1 has, in the region of adjacency between two reactor vessels 2, a flow-over wall region 12 which will be described below and which extends up to the ceiling wall 7 as seen in the vertical axis direction z and between the opposite side walls 11 in the transverse direction y and is adjacent thereto in each case, especially adjacent thereto in a gas- and/or liquid-tight manner and/or optionally even connected thereto.

[0113] In the present case, said flow-over wall region 12 is, merely by way of example, formed by a separate component (see FIG. 3a) which is fixedly connected to the front wall 3 and the back wall 4 of two mutually adjacent reactor vessels 2 (see FIGS. 2a and 2b). As is further evident from FIGS. 2a and 2b, the individual reactor vessels 2 are arranged one after another in the longitudinal direction x in such a way that a front reactor vessel 2, as seen in the longitudinal direction x, having a light-transmissive back wall is adjacent to a light-transmissive front wall 3 of a rear reactor vessel 2, as seen in the longitudinal direction x, with formation ii of a gap 13 as assembly space. In the example shown here, the free end regions of the front and back walls 3, 4 assigned to the flow-over wall region 12 are each connected, especially connected in a gas- and/or liquid-tight manner, to a lower frame subregion 14 of a peripherally encircling frame 15 of the flow-over wall region 12. As a result, the mutually assigned front and back walls 3, 4 of the mutually adjacent reactor vessels 2 both have a common flow-over wall region 12 which closes the gap 13 from above, based on the vertical axis direction z, and has here, merely by way of example, a plurality of vessel flow-over openings 16.

[0114] As is evident especially from FIG. 3a, the lower frame subregion 14 in the vertical axis direction z forms the connection region for the free end regions of the front walls 3 and back walls 4 of the assigned reactor vessels 2, whereas an upper frame subregion 17 in the vertical axis direction z is adjacent to the top wall 7, especially adjacent thereto in a gas- and/or liquid-tight manner and/or optionally even connected, preferably detachably connected, thereto.

[0115] The plurality of vessel flow-over openings 16 lying next to one another in the transverse direction are formed here by a plurality of connecting webs 18 which run in the vertical axis direction z between the upper frame subregion 17 and the lower frame subregion 14 and which preferably simultaneously form flow guide elements.

[0116] Alternatively, what could also be provided, however, is only a single vessel flow-over opening 16 without flow guide elements or connecting webs 18 (not depicted) or else a vessel flow-over opening 16 into which one or more flow guide elements 18a protrude, as is depicted in FIG. 3c merely by way of example.

[0117] As is evident especially from FIGS. 2a and 2b when looked at together, this arrangement of the flow-over wall region 12 between the mutually assigned front and back walls 3, 4 of mutually adjacent reactor vessels 2 gives rise to, in each case, an upper flow-over region, based on the vertical axis direction z, through which a nutrient medium can flow or flow over from a rear reactor chamber 9 of a front reactor vessel 2 into a front reactor chamber 8 of a rear reactor vessel 2.

[0118] According to an alternative embodiment, the flow-over wall region 12 can, however, also be integral with the free end region of the back wall 4 of the reactor vessel 2. This is shown schematically in FIG. 9a. Here, a free end region of a front wall 3 of a directly adjacent reactor vessel 2 is then likewise connected to the flow-over wall region 12 to form the common flow-over wall region 12 (see arrow 42).

[0119] According to a further alternative embodiment, the flow-over wall region 12 can, however, also be integral with the free end region of the front wall 3 of the reactor vessel 2. This is shown schematically in FIG. 9b. Here, a free end region of a back wall 4 of a directly adjacent reactor vessel 2 is then likewise connected to the flow-over wall region 12 to form the common flow-over wall region 12 (see arrow 42).

[0120] In an embodiment according to FIGS. 9a and 9b, it is evident that identical parts also arise in turn, since the reactor vessels 2 only have to be rotated 180° in order to form a flow-over wall region 12 arranged on a front wall 3 or a flow-over wall region 12 arranged on a back wall 4.

[0121] What was last mentioned also applies to the further alternative embodiment shown in FIG. 10, in which the flow-over wall region 12 is multi-piece and a first front-wall-side flow-over wall region element 12a is integral with the free end region of the front wall 3 of the reactor vessel 2 and a second back-wall-side flow-over wall region element 12b is integral with the free end region of the back wall 4 of the reactor vessel 2. The front-wall-side flow-over wall region element 12a and the back-wall-side flow-over wall region element 12b of two mutually adjacent reactor vessels 2 are then connected to one another to form the common flow-over wall region 12, which is indicated by the arrow 44 in what is depicted by FIG. 10. In principle, such a solution would also be possible with flow-over wall region elements 12a, 12b which are designed as separate components and only have to be connected to the free end regions of the assigned walls as part of preassembly.

[0122] A similar structure to the flow-over wall region 12 is also shown by the partition wall 6 in connection with its partition-wall flow-through openings 10, which have already been briefly addressed above.

[0123] As is evident especially from FIG. 8a, the partition wall 6 has, in the wall region near the bottom wall, a peripherally encircling frame region 19, whose lower frame subregion 20 in the vertical axis direction x is adjacent to the bottom wall 6, especially adjacent thereto in a gas- and/or liquid-tight manner and/or optionally even connected, preferably detachably connected, thereto.

[0124] Here, the partition wall 6 also has, by of example, a plurality of partition-wall flow-through openings 10 lying next to one another in the transverse direction y, which partition-wall flow-through openings are formed by a multiplicity of connecting webs 21 which run between opposite frame parts and which preferably simultaneously form flow guide elements.

[0125] As a result, the nutrient medium can also flow from the front reactor chamber 8 into the rear reactor chamber 9, and so an altogether vertically meandering flow path of the nutrient medium in the photobioreactor 1 arises.

[0126] Alternatively, what could also be provided, however, is only a single partition-wall flow-through opening 10 without flow guide elements or connecting webs 21 (not depicted) or else a partition-wall flow-through opening 10 into which one or more flow guide elements 21a protrude, as is depicted in FIG. 8b merely by way of example.

[0127] As is further evident especially from FIGS. 2a and 2b, the front wall 3 of the forwardmost reactor vessel 2 in the longitudinal direction x or flow-through direction has a first wall-type and/or plate-type bridging element 22 which, proceeding from the free end region of the front wall 3, extends up to the top wall and is adjacent thereto, especially adjacent thereto in a gas- and/or liquid-tight manner and/or optionally even connected thereto.

[0128] The same applies in an analogous manner to the back wall 4 of the rearmost reactor vessel 2 in the longitudinal direction x or flow-through direction, which reactor vessel has a second wall-type and/or plate-type bridging element 23 which likewise extends up to the top wall 7 and is adjacent thereto, especially adjacent thereto in a gas- and/or liquid-tight manner and/or optionally even connected thereto.

[0129] Such a structure of a photobioreactor 1, in which bridging elements 22, 23 are used on the opposite free end sides of the photobioreactor 1 in addition to flow-over wall regions 12 in the region of adjacency between two reactor vessels 2, ensures that reactor vessels of an identical basic structure can be used in each case, specifically irrespective of the respective position of the reactor vessels in the photobioreactor.

[0130] The first and second bridging elements 22 and 23 are preferably separate components which have to be connected to the respective wall region of the reactor vessel 2. However, this is not a mandatory measure. In principle, it would namely also be possible for the front wall of the forwardmost reactor vessel 2 as well as the back wall of the rearmost reactor vessel 2 to be already formed from the outset with such a height that the front wall 3 of the forwardmost reactor vessel 2 as well as the back wall 4 of the rearmost reactor vessel 2 extend upward, in the vertical axis direction z, up to the top wall 7, where they are adjacent.

[0131] As is further evident especially from FIGS. 4a and 4b when looked at together, the second bridging element 23 can be designed essentially analogously to the flow-over wall region 12 of FIGS. 3a and 3b in order, for example, to form an outlet 24 having at least one outlet opening 25, preferably a plurality of outlet openings 25. Here too, the plurality of outlet openings 25 are again formed by providing connecting webs 26 between opposite frame subregions. Moreover, a nozzle-type overflow connection 27 extends outwardly from the mouth region of the outlet 24, so that a defined overflow is created, for example to a further photobioreactor connected thereto of essentially identical or same design or else as an outlet to a continuous belt filter 28 depicted here by way of example. Said continuous belt filter 28 will be described in more detail below.

[0132] Because the partition wall 6 and the flow-over wall region 12 and optionally also the bridging elements 22, 23 each extend up to the top wall 7 and are adjacent thereto, specifically preferably adjacent in a contact and abutment connection without a gap space, preferably adjacent in a gas- and/or liquid-tight manner, the result is an altogether stable structure, since the individual walls or wall regions then extend up to the top wall 7 and can be supported there, for example can also be accommodated in a groove-shaped recess, for example can also be detachably latched. What was last mentioned allows not only a particularly advantageous seal, but also a functionally reliable arrangement of the top wall 7 and of the individual walls and wall regions in the respectively desired position. For the partition wall 6, this additionally also applies in an analogous manner to the connection thereof to the bottom wall 5.

[0133] As is evident especially from FIG. 2a in conjunction with FIG. 2b, a plurality of lighting elements 29 are arranged in each case in the gap 13 between the mutually adjacent reactor vessels 2, specifically in such a way, by way of example here, that a plurality of rows of lighting elements 29a, 29b, 29c and 29d extending in the transverse direction y are provided which are spaced apart from one another in the vertical axis direction z, specifically preferably evenly spaced apart from one another in the vertical axis direction z as depicted here by way of example.

[0134] The individual rows of lighting elements 29a, 29b, 29c and 29d can, for example, be lighting elements 29 in the form of LED light strips, to name just one example, the LEDs of which as lighting bodies can emit light both through the front wall 3 and through the back wall 4 of two mutually adjacent reactor vessels into the respective reactor chambers of the reactor vessels 2. This is depicted merely by way of example in connection with the two reactor vessels 2 on the left in the image plane of FIG. 2a.

[0135] Alternatively, the lighting elements 29, for example in the form of LED light strips, can, however, also be arranged or formed in the gap 13 in such a way that light is alternately merely emitted into one of the two assigned reactor vessels 2, as depicted in connection with the two reactor containers 2 on the right in the image plane of FIG. 2a. In the example of the right-hand side of the image of FIG. 2a that is shown and not to be understood as definitive, the lighting elements 29 arranged above one another in the vertical axis direction z moreover, merely by way of example, alternately radiate here (as seen from top to bottom) through the back wall 4 of the front reactor vessel 2, then through the front wall 3 of the rearmost reactor vessel 2, then again through the back wall 4 of the front reactor vessel 2 and lastly again through the front wall 3 of the rearmost reactor vessel 2. It is evident that other arrangements and transilluminations are of course also always possible.

[0136] These two lighting situations, depicted merely by way of example in FIG. 2a, based on the lighting elements 29 or based on the rows of lighting elements 29a to 29d are intended to show that it is particularly advantageous to form regions illuminated with differing brightness 30, 31 in the respective reactor chambers 8, 9, said regions illuminated with differing brightness 30, 31 preferably being regions lying one after another in the flow direction of the vertical meandering flow. In the present example, the regions 30 are thus illuminated more brightly than the regions 31, thereby yielding a certain bright/dark effect which has an advantageous effect on the growth of microorganisms, in particular on the growth of phytoplankton such as microalgae.

[0137] In the solution according to the invention, flow-over through the partition wall 6 between the individual reactor chambers 8, 9 or flow-over through the flow-over wall region 12 between the individual reactor vessels 2 is then advantageously effected by flow-over openings 10, 16 which are tailored to the particular use and which can be geometrically designed in such a way that specific influencing of the flow conditions of the vertically meandering flow can be achieved in the particular flow-over region, for example in such a way that specific gentle turbulences or eddies can be brought about there, which, for example, counteract sedimentation movement of microorganisms produced, without impairing the flow path as such.

[0138] As is evident from FIGS. 2a and 2b, a stiffening element 32 can be provided in the gap 13 between the respectively mutually adjacent reactor vessels, preferably in the region above the transition region from the front and/or back wall 3, 4 to the bottom wall 5, for example a stiffening element 32 which downwardly closes the gap 13. Said stiffening element 32 can extend over a specified length in the transverse direction y, for example even completely extend between the opposite side walls 11.

[0139] As is moreover further evident from FIGS. 1, 2a and 2b when looked at together, a plurality of feed nozzles 33 spaced apart in the transverse direction are provided in each case in the near-bottom-wall region of the reactor vessels 2, here in each case in the region of the rear reactor chamber 9 on the bottom wall 5, by means of which feed nozzles a medium, especially CO2 or a CO2-containing medium, is introducible into the reactor vessel from outside the reactor vessel 2.

[0140] The mouth opening of the feed nozzles is preferably oriented in the flow direction (cf. especially FIG. 2a), so that, when the medium is injected, the flow of the nutrient medium is supported in the flow direction. Moreover, by means of such an injection, deposits in the rear reactor chamber, especially in the bottom wall region, may also be reliably avoided.

[0141] As is evident especially from FIGS. 1 and 2a when looked at together, the first bridging element 22 can be designed differently, for example as a closed wall element 22a (to the left of the dividing line T) or, analogously to the flow-over wall region 12, be provided with flow-over openings 22b (to the right of the dividing line T). This depends, for example, on how the photobioreactor 1 will be specifically used or employed. If the photobioreactor 1 will be used as an individual reactor or as the first reactor of a reactor cascade, then the first bridging element 22 can be designed as a closed wall element 22a and the nutrient medium is then run or fed in via the inlet 34, which is only drawn in schematically in FIG. 2a.

[0142] By contrast, if the photobioreactor 1 is part of a reactor cascade and does not form the first photobioreactor here, what can be provided is that the first bridging element 22 is provided with the flow-over openings 22b, which are then flow-coupled to the outlet 24 of a preceding photobioreactor 1, specifically preferably via the overflow connection 27 to which the first bridging element 22 is coupled (not depicted in detail here).

[0143] In connection with FIGS. 2a and 2b, the first bridging element 22 is designed here, by way of example, as a closed wall element 22a.

[0144] As is further evident from FIG. 2a, the inlet 34 is further coupleable to a feed line 34a, by means of which fresh nutrient medium 34a can be fed to the photobioreactor 1 at given times.

[0145] Furthermore, the inlet 34 is connected to a nutrient medium line designed here as a return line 34b, which, here by way of example, exits from the last reactor vessel 2 and by means of which the nutrient medium is circulated via the inlet 34. For this purpose, a pump as conveying device can in principle be switched into the return line 34b. However, the conveying device in the solution according to the invention is particularly preferably formed by an air-lift arrangement 35 in which a certain working medium, preferably air, most preferably CO2-enriched and/or filtered air, is introduced into the return line 34b guided toward the inlet 34, which working medium conveys the nutrient medium in the direction of the inlet 34.

[0146] As further depicted, in this circulation of the nutrient medium, a portion of the nutrient medium is preferably extracted from the rearmost reactor vessel 2 in the longitudinal direction x or flow-through direction and then fed back to the forwardmost reactor vessel 2 in the longitudinal direction x or flow-through direction. However, a deviation from this may also be made, for example in such a way that a plurality of return lines are provided which branch off from a plurality of reactor vessels and are guided toward the inlet. Alternatively or additionally, an inlet can equally also be provided in connection with other or further reactor vessels.

[0147] Here, the air-lift arrangement 35 thus simultaneously serves as a circulating device for the liquid nutrient medium in the photobioreactor 1, i.e., as a circulating device for guiding the nutrient medium in the desired manner through the photobioreactor 1 in a vertically meandering manner. As already frequently stated above, such an air-lift arrangement 35 is particularly gentle on the product. However, the invention can in principle can be carried out with any type of circulating device.

[0148] In the schematic embodiment in principle according to FIG. 2a, what is downstream of the photobioreactor 1 is the continuous belt filter 28, in which a continuous filter cloth 36 is circulated between a filtering section 37 and a section 38 in which the filtered product 39 is removed from the filter cloth 36. This is only depicted extremely schematically in FIG. 2a.

[0149] As can moreover be further gathered from FIG. 2a, the filtered nutrient medium 40 can optionally be returned to the nutrient medium circulation via a further return line 34c.

[0150] From FIG. 2a, it is moreover further evident that the feed nozzles 33 can likewise be coupled to a feed line 33a, via which, for example, CO2-enriched medium, for example CO2-enriched air, can be fed.

[0151] It is evident that valves, check valves and other blocking elements or control elements, by means of which media flow is controlled or regulated, can of course be arranged in the respective media-guiding lines in a customary manner.

[0152] Furthermore, a heating and/or cooling element 41 can be arranged on the bottom wall 5 of each of the reactor vessels, by means of which heating and/or cooling element the nutrient medium accommodated in the particular reactor container 2 can be appropriately temperature-controlled. This is only depicted by way of example and schematically in FIG. 6.

[0153] ii And lastly, the top wall 7 can be provided with one or more ventilation devices 45, which, for example, are formed by ventilation fans. This is only depicted extremely schematically and by way of example in FIG. 2a. By means of these ventilation devices 45, a gas, especially oxygen-containing gas, accumulating between the top wall 7 and the nutrient medium can be extracted from the interior of the photobioreactor 1, especially from the reactor vessels 2. In principle, a top-wall-side ventilation device 45 can be assigned to each reactor vessel 2.

LIST OF REFERENCE SIGNS

[0154] 1 Photobioreactor

[0155] 2 Reactor vessel

[0156] 3 Front wall

[0157] 4 Back wall

[0158] 5 Bottom wall

[0159] 6 Partition wall

[0160] 7 Top wall

[0161] 8 Front reactor chamber

[0162] 9 Rear reactor chamber

[0163] 10 Partition-wall flow-through openings

[0164] 11 Side walls

[0165] 12 Flow-over wall region

[0166] 12a First flow-over wall region element

[0167] 12b Second flow-over wall region element

[0168] 13 Gap

[0169] 14 Lower frame subregion

[0170] 15 Frame

[0171] 16 Vessel flow-over openings

[0172] 17 Upper frame subregion

[0173] 18 Connecting webs

[0174] 18a Flow guide element

[0175] 19 Frame region

[0176] 20 Lower frame subregion

[0177] 21 Connecting webs

[0178] 21a Flow guide element

[0179] 22 First bridging element

[0180] 22a Closed wall element

[0181] 22b Flow-over openings

[0182] 23 Second bridging element

[0183] 24 Outlet

[0184] 25 Outlet openings

[0185] 26 Connecting web

[0186] ¢Overflow connection

[0187] 28 Continuous belt filter

[0188] 29 Lighting elements

[0189] 29a Row of lighting elements

[0190] 29b Row of lighting elements

[0191] 29c Row of lighting elements

[0192] 29d Row of lighting elements

[0193] 30 More brightly illuminated region

[0194] 31 More darkly illuminated region

[0195] 32 Stiffening element

[0196] 33 Feed nozzles

[0197] 33a Feed line

[0198] 34 Inlet

[0199] 34a Feed line

[0200] 34b Return line

[0201] 34c Return line

[0202] 35 Air-lift arrangement

[0203] 36 Filter cloth

[0204] 37 Filtering section

[0205] 38 Section

[0206] 39 Filtered product

[0207] 40 Filtered nutrient medium

[0208] 41 Heating and/or cooling element

[0209] 42 Arrow

[0210] 43 Arrow

[0211] 44 Arrow

[0212] 45 Ventilation device