METHOD AND APPARATUS FOR CO2 SEQUESTRATION

• US 20070289206A1
• Filed: 06/13/2007
• Published: 12/20/2007
• Est. Priority Date: 06/14/2006
• Status: Active Grant

• Current Assignee: Malcolm Glen Kertz
• Original Assignee: Malcolm Glen Kertz
• Inventors: Kertz, Malcolm Glen
• Granted Patent: US 8,372,632 B2
• Time in Patent Office: Days
• US Class Current: 47/1.400
• CPC Class Codes: A01G 15/00 Devices or methods for influencing weather conditions
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 53/84 Biological processes
• CPC Class Codes: C12M 21/02 Photobioreactors culturing algae A01G33/00, A01H4/001, C12N1/12
• CPC Class Codes: C12M 23/14 Bags
• CPC Class Codes: C12M 23/18 Open ponds; Greenhouse type or underground installations
• CPC Class Codes: C12M 23/50 Means for positioning or orientating the apparatus C12M41/08 takes precedence
• CPC Class Codes: C12M 23/58 Reaction vessels connected in series or in parallel combinations of bioreactors with other apparatus, C12M43/00
• CPC Class Codes: C12M 27/20 Baffles; Ribs; Ribbons; Auger vanes
• CPC Class Codes: C12M 33/18 Rollers
• CPC Class Codes: C12M 33/22 Settling tanks; Sedimentation by gravity settling tanks per se B01D21/02
• CPC Class Codes: C12M 39/00 Means for cleaning the apparatus or avoiding unwanted deposits of microorganisms apparatus for cleaning laboratory receptacles or instruments B01L13/02; cleaning in general B08B
• CPC Class Codes: C12M 43/04 Bioreactors or fermenters combined with combustion devices or plants, e.g. for carbon dioxide removal C12M43/06 takes precedence; recovery of carbon dioxide C12F3/02
• CPC Class Codes: C12N 1/12 Unicellular algae; Culture media therefor as new plants A01H13/00
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/59 Biological synthesis; Biological purification
• CPC Class Codes: Y02P 60/20 Reduction of greenhouse gas [GHG] emissions in agriculture, e.g. CO2

Abstract

A method and apparatus for sequestering CO₂ using algae comprises a plurality of vertically suspended bioreactors, each bioreactor being translucent and including a flow channel formed by a plurality of baffles. A culture tank contains a suspension of water and at least one algae and includes a plurality of gas jets for introducing a CO₂-containing gas into the suspension. The culture tank is in fluid communication with an inlet in each channel for flowing the suspension through the channel in the presence of light. A pump pumps the suspension into the channel inlet.

Claims

1. An apparatus for sequestering CO₂ comprising one or more translucent bioreactors having a channel therethrough for the continuous flow of a suspension containing algae in the presence of light.

2. The apparatus of claim 1 further including a culture tank containing a suspension of water and at least one algae, wherein said culture tank comprises a plurality of gas jets for introducing a CO₂-containing gas into said suspension.

3. The apparatus of claim 2 wherein the bioreactor has an inlet located at the top of the one or more bioreactors, each inlet being in fluid communication with the culture tank.

4. The apparatus of claim 3 further including a pump for pumping the suspension to the inlet of the one or more bioreactors.

5. The apparatus of claim 2 wherein the one or more bioreactors has a plurality of baffles forming the channel.

6. The apparatus of claim 5 wherein said plurality of baffles are arranged horizontally.

7. The apparatus of claim 5 wherein said plurality of baffles are arranged at an angle

8. The apparatus of claim 7 wherein said plurality of baffles are arranged at an upward angle.

9. The apparatus of claim 7 wherein said plurality of baffles are arranged at different angles.

10. The apparatus of claim 1 wherein the one or more bioreactors is suspended vertically.

11. The apparatus of claim 1, wherein the one or more bioreactors is translucent.

12. The apparatus of claim 1 wherein the one or more bioreactors are made of a flexible polymeric material.

13. The apparatus of claim 12, wherein the polymeric material is from the group comprising polyethylene, polypropylene, polystyrene, polyester, polyacrylic acid, or combinations thereof.

14. The apparatus of claim 1 wherein the one or more bioreactors includes a gas inlet.

15. The apparatus of claim 1 wherein the channel has a plurality of vertical baffles.

16. The apparatus of claim 1, wherein the algae comprise Chlorella.

17. The apparatus of claim 1, wherein the channel is no more than about 3 inches wide.

18. The apparatus of claim 1 wherein the one or more bioreactors are arranged in a matrix configuration.

19. The apparatus of claim 1, further comprising an artificial light source.

20. The apparatus of claim 1, where the bottom of the one or more bioreactors includes an outlet that returns said suspension to the culture tank.

21. The apparatus of claim 1, further including an algae harvester in fluid communication with the culture tank.

22. The apparatus of claim 2, further comprising a water recycler in fluid communication with the culture tank.

23. The apparatus of claim 1, wherein each bioreactor is disposed between at least two members, said at least two members are movably disposed horizontally on either face of each bioreactor.

24. A method for sequestering CO₂ comprising:

forming a suspension of water and algae;

flowing the suspension through a channel formed in one or more translucent bioreactors;

exposing the algae to light; and

converting the CO₂ into an organic compound by photosynthesis.

25. The method of claim 24 further comprising

introducing a CO₂-containing gas into a culture tank filled with the suspension such that the CO₂ is dissolved in the suspension;

and

passing the suspension from said culture tank through the channel by gravity flow.

26. The method of claim 24 wherein the channel includes a plurality of baffles that create a vortex in the flow of the suspension through the channel.

27. The method of claim 26 where the plurality of baffles are angled upward to create the vortex.

28. The method of claim 24 further comprising pumping the suspension to an inlet to the channel.

29. The method of claim 24 further comprising passing the suspension through the channel at a flow rate of about 10 gallons per hour.

30. The method of claim 25 wherein the gas is ambient air.

31. The method of claim 24 wherein the suspension is exposed to sunlight.

32. The method of claim 24 further comprising returning the suspension to the culture tank

33. The method of claim 24 further comprising monitoring the light level that penetrates each channel.

34. The method of claim 24 further comprising introducing a CO₂-containing gas into the one or more bioreactors.

35. The method of claim 26 further comprising continuing the flow of the suspension through the channel until the light level reaches less than about 250 footcandles.

36. The method of claim 35 further comprising removing the algae by filtration after the light level reaches about 250 footcandles.

37. The method of claim 24 further comprising measuring the cell density of the suspension.

38. The method of claim 24 wherein the flowing the suspension through a channel formed in one or more translucent bioreactors comprises flowing the suspension at a flow rate ranging from about 5 cm/s to about 15 cm/s.

39. The method of claim 24 wherein the flowing the suspension through a channel formed in one or more translucent bioreactors comprises flowing the suspension through the channel under sterile conditions.