APPARATUS AND METHODS FOR PRODUCTION OF BIODIESEL

• US 20080220515A1
• Filed: 01/17/2008
• Published: 09/11/2008
• Est. Priority Date: 01/17/2007
• Status: Active Grant

• Current Assignee: MIP Incorporated
• Original Assignee: MIP Incorporated
• Inventors: McCall, Joe
• Granted Patent: US 7,950,181 B2
• Time in Patent Office: Days
• US Class Current: 435/292.1
• CPC Class Codes: C12M 21/02 Photobioreactors culturing algae A01G33/00, A01H4/001, C12N1/12
• CPC Class Codes: C12M 21/12 for producing fuels or solvents C12M21/04 takes precedence; liquid carbonaceous fuels C10L1/00, solid fuels C10L5/00
• CPC Class Codes: C12M 31/06 Lenses
• CPC Class Codes: C12M 33/22 Settling tanks; Sedimentation by gravity settling tanks per se B01D21/02

Abstract

A photobioreactor includes a cultivation zone configured to contain a liquid culture medium and facilitate growth of a microalgae biomass, a plurality of parallel edge-lit light transmitting devices mounted within the cultivation zone, and a collection zone oriented in relation to the cultivation zone such that at least a portion of the liquid culture medium and microalgae from the cultivation zone may be periodically harvested. Methods for illuminating algae, for dissolving materials into an algae medium, for extracting oil from algae, and for producing biodiesel from algal oil are also provided.

Claims

1. A method for illuminating an algae, comprising:

concentrating a stream of light;

transmitting the stream of light to an illuminator having a first surface and a second surface opposite the first surface;

transmitting the stream of light within the illuminator between the first and second surface to a reflector disposed between the first surface and the second surface;

radiating the stream of light through either the first surface or the second surface of the illuminator; and

illuminating the algae with the stream of light.

2. The method of claim 1, wherein the stream of light is concentrated with a light concentrator having an aperture, and the stream of light is transmitted through the aperture of the light concentrator to the illuminator.

3. The method of claim 1, wherein the stream of light is concentrated with a parabolic concentrator.

4. The method of claim 1, wherein the stream of light is concentrated with a compound parabolic concentrator.

5. A method of extracting an algal oil from an algae cultivated in a photobioreactor, comprising:

placing the algae in a space between a rotor and a housing;

generating relative rotational movement between the rotor and the housing so as to agitate the algae;

breaking a cell wall of the algae to allow algal oil to release from the algae into a suspension;

flocculating the suspension with a standing wave to isolate the algal oil from a pulp comprising the cell wall; and

removing the algal oil and the pulp from the suspension.

6. The method of claim 5, wherein the rotor is disposed at least partially within the housing in a concentric arrangement, and the step of generating relative rotational movement between the rotor and the housing comprises creating cavitation in the space between the rotor and the housing to agitate the algae.

7. A method of extracting an algal oil from an algae cultivated in a photobioreactor, comprising:

placing the algae in an agitator;

breaking a cell wall of the algae with the agitator to allow algal oil to release from the algae into a suspension;

transferring the suspension from the agitator to an aggregation tank;

creating a standing sonic wave in the suspension contained within the aggregation tank with a standing sonic wave generator;

aggregating a pulp comprising the cell wall at a pressure node formed by the standing sonic wave; and

allowing the pulp to settle toward the bottom of the aggregation tank, separate from the algal oil.

8. The method of claim 7, further comprising:

removing the algal oil through a first passage disposed toward a top portion of the aggregation tank; and

removing the pulp through a second passage disposed toward a bottom portion of the aggregation tank.

9. A method of extracting an algal oil from an algae, comprising:

placing the algae in a space between a rotor and a housing, wherein the rotor is disposed at least partially within the housing in a concentric arrangement;

generating relative rotational movement between the rotor and the housing so as to create cavitation in the space between the rotor and the housing and agitate the algae;

breaking a cell wall of the algae to allow algal oil to release from the algae into a suspension;

transferring the suspension to an aggregation tank, the suspension comprising the algal oil and the cell wall;

creating a standing sonic wave in the suspension with a standing sonic wave generator;

aggregating a pulp comprising the cell wall at a pressure node;

allowing the pulp to settle toward the bottom of the aggregation tank, separate from the algal oil;

removing the algal oil through a first passage disposed toward a top portion of the aggregation tank;

removing the pulp through a second passage disposed toward a bottom portion of the aggregation tank;

transferring a volume comprising at least a portion of the suspension remaining in the aggregation tank to the space between the rotor and the housing; and

infusing the volume with carbon dioxide and nutrients via cavitation.

10. A photobioreactor for growing a microalgae biomass, comprising:

a cultivation zone configured to contain a liquid culture medium and facilitate growth of the microalgae biomass; and

a light concentrator mounted above the cultivation zone, the light concentrator having a light concentration surface that concentrates a stream of light and directs the stream of light toward an illuminator,

wherein the illuminator comprises a first surface and a second surface opposite the first surface, and a reflector disposed between the first surface and the second surface that reflects the stream of light through the first surface or the second surface of the illuminator so as to illuminate the microalgae biomass.

11. The photobioreactor of claim 10, wherein the light concentrator comprises an aperture, and the light concentration surface comprises a parabolic shape.

12. The photobioreactor of claim 10, further comprising a cleaning element that runs along the first surface or the second surface of the illuminator.

13. The photobioreactor of claim 12, wherein the cleaning element comprises a brushing apparatus or a scraping apparatus.

14. The photobioreactor of claim 10, wherein the light concentrator comprises a compound parabolic concentrator.

15. The photobioreactor of claim 10, further comprising a collection zone having a rectangular configuration with a first and second pair of opposite sidewalls, and has a total volume sufficient to harvest at least half of the volume of the cultivation zone at periodic intervals.

16. The photobioreactor of claim 10, further comprising a zone for recovering heat from the cultivation zone, and cooling the same.

17. A culture unit for cultivating microalgae, comprising:

a cultivation zone configured to contain a liquid culture medium and facilitate growth of the microalgae;

a light concentrator mounted above the cultivation zone, the light concentrator having a light concentration surface that concentrates a stream of light and directs the stream of light toward an illuminator;

a collection zone in fluid communication with the cultivation zone;

a hydrodynamic separation zone in fluid communication with the cultivation zone; and

a flocculation tank in fluid communication with the hydrodynamic separation zone;

wherein the hydrodynamic separation zone comprises a cavitation mixer having a rotor and a housing, wherein the rotor is disposed at least partially within the housing in a concentric arrangement.

18. The culture unit of claim 17, wherein the cavitation mixer is configured to separate at least a portion of the microalgae and liquid culture medium into a solid phase containing a solid component of the microalgae and at least one liquid phase.

19. The culture unit of claim 17, further comprising a standing sonic wave generator configured to create a standing sonic wave within the flocculation tank.

20. The culture unit of claim 17, wherein the illuminator comprises a first surface and a second surface opposite the first surface, and a reflector disposed between the first surface and the second surface that reflects the stream of light through the first surface or the second surface of the illuminator so as to illuminate the microalgae.

21. The culture unit of claim 17, further comprising an oxygen container in fluid communication with the cultivation zone via a conduit.