Algae cultivation systems and methods

• US 8,033,047 B2
• Filed: 10/23/2008
• Issued: 10/11/2011
• Est. Priority Date: 10/23/2007
• Status: Active Grant

• Current Assignee: Sartec
• Original Assignee: Sartec
• Inventors: Rasmussen, Mark Axel, McNeff, Larry C., McNeff, Clayton V.
• Primary Examiner(s): Swiatek; Rob
• Assistant Examiner(s): Hayes; Kristen
• Application Number:
  US12/257,008
• Publication Number:
  US 20090126265A1
• Time in Patent Office: 1,083 Days
• Field of Search: 47/14, 435/292.1
• US Class Current: 47/1.4
• CPC Class Codes: A01G 33/00 Cultivation of seaweed or algae
• CPC Class Codes: C12M 21/02 Photobioreactors culturing algae A01G33/00, A01H4/001, C12N1/12
• CPC Class Codes: C12M 23/18 Open ponds; Greenhouse type or underground installations
• CPC Class Codes: C12M 23/38 Caps; Covers; Plugs; Pouring means
• CPC Class Codes: C12M 31/08 by conducting or reflecting elements located inside the reactor or in its structure
• CPC Class Codes: C12M 41/34 of gas
• CPC Class Codes: Y02A 40/80 in fisheries management

Abstract

An algae cultivation system and method. In an embodiment, an algae cultivation system is included. The algae cultivation system can include a cultivation tank, a plurality of light transmitting elements configured to be at least partially submerged in a liquid medium disposed within the cultivation tank, wherein the light transmitting elements increase the effective surface area of the liquid medium exposed to light, and a plurality of gas injectors configured to emit gas into the liquid medium. In an embodiment a method of culturing algae is included. The method can include measuring the amount of carbon dioxide in a cultivation system and modulating the amount of light being supplied to the cultivation system based on the measured amount of carbon dioxide. In an embodiment, a method of culturing algae can include measuring the amount of light being input into a cultivation system and modulating the amount of carbon dioxide being supplied to the cultivation system based on the measured amount of light. Other embodiments are also described herein.

Claims

1. An algae cultivation system comprising:

a cultivation tank;

a plurality of light transmitting elements configured to be at least partially submerged in a liquid medium disposed within the cultivation tank, wherein the light transmitting elements increase the effective surface area of the liquid medium exposed to light;

a plurality of gas injectors configured to emit gas into the liquid medium; and

cap members disposed on top of the light transmitting elements, the cap members configured to concentrate light into the body of the light transmitting elements.

2. The algae cultivation system of claim 1, the light transmitting elements comprising a conical shape.

3. The algae cultivation system of claim 1, the light transmitting elements comprising a cylindrical shape.

4. The algae cultivation system of claim 1, the gas injectors positioned so that at least a portion of gas bubbles released from the gas injectors contact an exterior surface of the light transmitting elements after being released from the gas injectors.

5. The algae cultivation system of claim 1, the cultivation tank having a depth of greater than about one foot and less than about twenty feet.

6. The algae cultivation system of claim 1, further comprising a heat control system configured to maintain the liquid medium at a temperature of between about 50 and about 80 degrees Fahrenheit.

7. The algae cultivation system of claim 1, further comprising a translucent cover disposed over the cultivation tank.

8. The algae cultivation system of claim 1, further comprising an ingress conduit in fluid communication with the cultivation tank and an egress conduit in fluid communication with the cultivation tank.

9. The algae cultivation system of claim 8, further comprising a first pump in fluid communication with the ingress conduit and a second pump in fluid communication with the egress conduit.

10. The algae cultivation system of claim 9, further comprising a controller configured to operate the first pump and the second pump.

11. An algae cultivation system comprising:

a cultivation tank;

a plurality of light transmitting elements configured to be at least partially submerged in a liquid medium disposed within the cultivation tank, wherein the light transmitting elements increase the effective surface area of the liquid medium exposed to light;

a plurality of gas injectors configured to emit gas into the liquid medium;

a frame interconnecting a plurality of the light transmitting elements and suspending them within the liquid medium, wherein the frame is configured to move with respect to the cultivation tank in order to lift the light transmitting elements out of the liquid medium; and

a carbon dioxide sensor, the system configured to modulate the amount of light input into the cultivation tank based on data from the carbon dioxide sensor.

12. An algae cultivation system comprising:

a cultivation tank;

a plurality of light transmitting elements configured to be at least partially submerged in a liquid medium disposed within the cultivation tank, wherein the light transmitting elements increase the effective surface area of the liquid medium exposed to light;

a plurality of gas injectors configured to emit gas into the liquid medium; and

an iris mechanism disposed on the light transmitting elements.

13. An algae cultivation system comprising:

a cultivation tank;

a plurality of light transmitting elements configured to be at least partially submerged in a liquid medium disposed within the cultivation tank, wherein the light transmitting elements increase the effective surface area of the liquid medium exposed to light;

a plurality of gas injectors configured to emit gas into the liquid medium; and

a light sensor, the system configured to modulate the amount of carbon dioxide input into the cultivation tank based on data from the light sensor.

14. An algae cultivation system comprising:

a cultivation tank;

a plurality of light transmitting elements configured to be at least partially submerged in a liquid medium disposed within the cultivation tank, wherein the light transmitting elements increase the effective surface area of the liquid medium exposed to light;

a plurality of gas injectors configured to emit gas into the liquid medium; and

the light transmitting elements having an exterior surface comprising surface features configured to increase turbulence in the liquid medium as gas bubbles released from the gas injectors pass by, the surface features comprising a plurality of grooves.