Reactor plant and process for culturing phototropic microorganisms

• US 10,344,254 B2
• Filed: 03/06/2007
• Issued: 07/09/2019
• Est. Priority Date: 03/28/2006
• Status: Active Grant

• Current Assignee: Sartorius Stedim Biotech GmbH (Sartorius AG)
• Original Assignee: Sartorius AG
• Inventors: Kahlert, Wolfgang, Wilhelm, Bernd-Ulrich, Linke, Wolf-Dietrich
• Primary Examiner(s): Shen, Bin
• Application Number:
  US11/714,351
• Publication Number:
  US 20070231886A1
• Time in Patent Office: 4,508 Days
• Field of Search: 435243
• CPC Class Codes: C12M 21/02 Photobioreactors culturing algae A01G33/00, A01H4/001, C12N1/12
• CPC Class Codes: C12M 23/06 Tubular C12M23/08, C12M23/16 take precedence
• CPC Class Codes: C12M 23/44 Multiple separable units; Modules
• CPC Class Codes: C12M 27/02 Stirrer or mobile mixing elements
• CPC Class Codes: C12M 31/02 located outside the reactor
• CPC Class Codes: C12M 33/14 with filters, sieves or membranes
• CPC Class Codes: C12M 41/06 of illumination

Abstract

Reactor plant and process for culturing phototropic microorganisms with a reactor vessel and a photosynthetic module, which are connected with one another in a circulation circuit by a pump and can be controlled via a control unit, where in the circulation circuit or in the reactor vessel, a homogenizer is provided, where a light-intensity control of the photosynthetic module is provided, and where a bypass of the circulation circuit or of the reactor vessel with a filter device which is arranged externally of the reactor vessel for separating off extracellular products during the fermentation is provided.

Claims

1. A reactor plant (1) for culturing phototropic microorganisms in a culture medium, comprising:

a reactor vessel (2) through which the culture medium is circulated and a photosynthetic module (3) with a helically wound transparent tube (19) that communicates with the reactor vessel (2) via a circulation circuit (4) that includes a pump (5), the photosynthetic module (3) further including an illumination unit (20) aligned parallel to an axis of the helically wound transparent tube (19);

a control unit (6) controlling at least the reactor vessel (2) and light-intensity of the illumination unit (20) of the photosynthetic module (3), a comminuter (7) provided inside the reactor vessel (2) and an optical density sensor (9) having a portion provided inside the reactor vessel (2), the optical density sensor (9) being operative to measure optical density of the culture medium inside the reactor vessel (2) as a function of biomass concentration of the culture medium inside the reactor vessel (2), and a bypass (12, 12′

, 12″

) of the circulation circuit (4) or of the reactor vessel (2) being provided, the bypass (12, 12′

, 12″

) having a filter device (13, 13′

, 13″

) arranged externally of the reactor vessel for separating off extracellular products during the fermentation, the control unit (6) is connected to the photosynthetic module (3) and controls the light-intensity of the photosynthetic module (3) as a function of the biomass concentration of the culture medium as determined by the optical density of the culture medium in the reactor vessel (2) sensed by the optical density sensor (9).

2. The reactor plant of claim 1, wherein the illumination unit (20) includes a dimmer or switch for selectively controlling plural illumination sources (21) of the illumination unit (20).

3. The reactor plant of claim 1, wherein the illumination unit (20) has at least two illumination means that are independently operable for producing illumination with at least two different wavelengths.

4. The reactor plant of claim 1, wherein the illumination unit 20 is arranged within an internal space surrounded by the helical tube (19).

5. The reactor plant of claim 1, further comprising baffles arranged within the photosynthetic module (3) for generating a turbulent flow.

6. The reactor plant of claim 5, wherein the filter device (13, 13′

, 13″

) for separating off extracellular products is equipped with a cross-flow filter, a hollow-fiber filter or a membrane-adsorber filter.

7. The reactor plant of claim 1, further comprising a bypass (15, 15″

) of the circulation circuit (4) or of the reactor vessel (2) with a device (16, 16″

) for separating off biomass by means of cross-flow filter, hollow-fiber filter, centrifuge, membrane-adsorber filter or spin filter.

8. The reactor plant of claim 1, wherein the control unit (6) further is connected to the pump (5) and controls a speed of the pump (5) as a function of the optical density measured by the optical density sensor (9).

9. Process for culturing phototropic microorganisms in a culture medium using the reactor plant of claim 1, where the culture medium together with the microorganisms is pumped in a circulation circuit (4) from a reactor vessel (2) through a photosynthetic module (3) by means of a pump (5), the delivery rate of the pump (5) being regulatable as a function of at least one reference quantity, wherein the improvement comprises the steps wherein the culture medium is homogenized in a homogenizer (7) by comminution of its cell aggregates and in that extracellular products are separated off during the fermentation, for harvesting purposes, via cross-flow or hollow-fiber or membrane-adsorber filters arranged in a bypass (12, 12′

, 12″

) of the circulation circuit (4).

10. Process according to claim 9, characterized in that, to obtain intracellular products from a certain growth phase, a specific damaging to the cells'"'"' membrane is accomplished by the comminution in the homogenizer (7).

11. Process according to claim 10, characterized in that biomass is separated off via cross-flow, hollow-fiber, membrane-adsorber or spin filters arranged in a bypass (15, 15″

) of the circulation circuit (4).

12. Process according to claim 11, characterized in that the biomass which has been separated off is removed from the circulation circuit (4) and conveyed to further processing.

13. Process according to claim 11, characterized in that the biomass which has been separated off is recirculated with addition of fresh medium to the circulation circuit (4).

14. Process according to claim 10, characterized in that biomass is centrifuged, and separated off, in a centrifuge arranged in a bypass (15, 15″

) of the circulation circuit (4).

15. A reactor plant (1) for culturing phototropic microorganisms in a culture medium, comprising:

a reactor vessel (2) for containing the culture medium, the reactor vessel (2) including a comminuter (7) provided inside the reactor vessel (2) and an optical density sensor (9) having a portion provided inside the reactor vessel (2) for sensing an optical density of the culture medium in the reactor vessel (2) as a function of a biomass concentration of the culture medium inside the reactor vessel (2);

a photosynthetic module (3) having illumination unit (20) for producing intensity controlled illumination and a transparent tube (19) wound around the illumination unit (20);

a pump (5) in communication with the reactor vessel (2) and the photosynthetic module (3) for circulating the culture medium from the reactor vessel (2) to the photosynthetic module (3) and back to the reactor vessel (2); and

a control unit (6) communicating with the optical density sensor (9) and with the photosynthetic module (3), and the control unit (6) controlling a speed of the pump (5) and the intensity of the illumination produced by the illumination unit (20) as a function of the biomass concentration of the culture medium inside the reactor vessel (2) sensed by the optical density sensor (9).

16. The reactor plant of claim 15, wherein the control unit (6) controls the intensity of the illumination unit (20) by a dimmer or switch.

17. The reactor plant of claim 16, wherein the illumination unit (20) has at least two illumination means that are independently operable for producing light with at least two different wavelengths.