Algae bioreactor, system and process

• US 9,005,918 B2
• Filed: 12/15/2011
• Issued: 04/14/2015
• Est. Priority Date: 12/20/2010
• Status: Active Grant

• Current Assignee: DVO, Inc.
• Original Assignee: DVO, Inc.
• Inventors: Dvorak, Stephen W., Van Ornum, Douglas
• Primary Examiner(s): Carlson, Karen Cochrane
• Assistant Examiner(s): MOSS, NATALIE M
• Application Number:
  US13/995,240
• Publication Number:
  US 20130280757A1
• Time in Patent Office: 1,216 Days
• Field of Search: 435/41, 435/257.1, 435/283.1
• US Class Current: 435/41
• CPC Class Codes: C12M 21/02 Photobioreactors culturing algae A01G33/00, A01H4/001, C12N1/12
• CPC Class Codes: C12M 27/20 Baffles; Ribs; Ribbons; Auger vanes
• CPC Class Codes: C12M 29/06 Nozzles; Sprayers; Spargers; Diffusers per se B01F23/231, B01J19/26
• CPC Class Codes: C12M 31/08 by conducting or reflecting elements located inside the reactor or in its structure

Abstract

The present disclosure provides an algae bioreactor and process. The algae bioreactor includes a container with an inlet and an outlet. An algae suspension present in the container interior moves from an inlet to an outlet along a flowpath. A light assembly, a liftwall, and a gas conduit are located in the container interior. The gas conduit extends along a length of the container and emits gas bubbles into the algae suspension. A diffuser is located on a bottom wall of the container, The flowpath, the liftwall, the gas conduit, and the diffuser produce an active flow of the algae from the container inlet to the container outlet. The container may be a deep-vessel container.

Claims

1. An algae bioreactor comprising:

a container comprising a bottom wall, an inlet, an outlet, and an algae suspension in the container;

a flowpath moving from the inlet to the outlet;

a light assembly;

a liftwall forming a first flowpoint between the top of the liftwall and the suspension surface and a second flowpoint between the bottom of the liftwall and the bottom wall;

a gas conduit extending along a length of the container interior, the gas conduit emitting gas bubbles into the algae suspension; and

the flowpath and the emitted gas bubbles moving the algae in a helical motion around the liftwall.

2. The bioreactor of claim 1 wherein the liftwall is substantially parallel to the flowpath.

3. The bioreactor of claim 1 wherein the liftwall defines a first portion and a second portion in the container, the conduit located in the first portion and producing an upward fluid lift in the first portion.

4. The bioreactor of claim 3 comprising a diffuser located below the light assembly;

and

the flowpath, the emitted gas bubbles and the diffuser produce an active flow of the algae from the inlet to the outlet.

5. The bioreactor of claim 1 wherein the container holds the algae suspension under photosynthesis conditions.

6. The bioreactor of claim 1 wherein the liftwall comprises a light source.

7. The bioreactor of claim 1 wherein the container is a deep-vessel container.

8. The bioreactor of claim 1 comprising a light zone and a dark zone.

9. An algae bioreactor comprising:

a container comprising a bottom wall, an inlet, an outlet and an algae suspension;

a flowpath moving from the inlet to the outlet;

a light assembly;

a liftwall forming a first flowpoint between the top of the liftwall and the suspension surface and a second flowpoint between the bottom of the liftwall and the bottom wall;

a gas conduit extending along a length of the container interior, the gas conduit emitting gas bubbles into the algae suspension;

a diffuser located on a bottom wall of the container; and

the flowpath, the liftwall, the gas conduit, and the diffuser producing an active flow of the algae from the container inlet to the container outlet.

10. The bioreactor of claim 9 wherein the liftwall comprises a light source.

11. The bioreactor of claim 9 comprising a thermal element for heating at least a portion of the algae suspension;

and

the liftwall defines a thermal gradient in the algae suspension.

12. The bioreactor of claim 9 wherein the outlet is in fluid communication with a harvest tank.

13. The bioreactor of claim 9 wherein the bioreactor produces from about 1 kg algae/day to about 10,000 kg algae/day.

14. A process for producing algae comprising:

introducing an algae suspension into a container comprising a bottom wall, an inlet, an outlet, a light assembly, a liftwall, a gas conduit, and a diffuser wherein the liftwall forms a first flowpoint between the top of the liftwall and the suspension surface and a second flowpoint between the bottom of the liftwall and the bottom wall; and

actively flowing the algae suspension from the container inlet to the container outlet under photosynthesis conditions.

15. The process of claim 14 wherein the actively flowing comprises helically moving the algae around the liftwall.

16. The process of claim 14 comprising growing the algae to a harvest density.

17. The process of claim 16 comprising harvesting the algae at the harvest density from the outlet.

18. The process of claim 17 comprising producing a biofuel from the harvested algae.

19. The process of claim 14 comprising growing the algae in an exponential growth phase;

and

continuously harvesting the algae during the exponential growth phase.

20. The process of claim 14 comprising actively flowing the algae suspension through a deep-vessel container.