Photobioreactor systems and methods for treating CO2-enriched gas and producing biomass

• US 8,877,488 B2
• Filed: 08/12/2013
• Issued: 11/04/2014
• Est. Priority Date: 07/10/2006
• Status: Expired due to Fees

• Current Assignee: Algae Systems, LLC
• Original Assignee: Algae Systems, LLC
• Inventors: Lewnard, John L., Wu, Xiaoxi
• Primary Examiner(s): Beisner, William H
• Application Number:
  US13/965,173
• Publication Number:
  US 20130330810A1
• Time in Patent Office: 449 Days
• Field of Search: 435/292.1, 47/14
• US Class Current: 435/292.1
• CPC Class Codes: B01D 2251/95 Specific microorganisms
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 53/84 Biological processes
• CPC Class Codes: C02F 2103/18 from the purification of gaseous effluents
• CPC Class Codes: C02F 3/32 characterised by the animals or plants used, e.g. algae
• CPC Class Codes: C12M 21/02 Photobioreactors culturing algae A01G33/00, A01H4/001, C12N1/12
• CPC Class Codes: C12M 23/56 Floating elements
• 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
• CPC Class Codes: Y02W 10/37 using solar energy

Abstract

Certain embodiments and aspects of the invention relate to a photobioreactor including covered photobioreactor units through which a liquid medium stream and a gas stream flow. The liquid medium comprises at least one species of phototrophic organism therein. Certain methods of using the photobioreactor system as part of fuel generation system and/or a gas-treatment process or system at least partially remove certain undesirable pollutants from a gas stream. In certain embodiments, a portion of the liquid medium is diverted from a photobioreactor unit and reintroduced upstream of the diversion position. In certain embodiments, the disclosed photobioreactor system, methods of using such systems, and/or gas treatment apparatus and methods provided herein can be used as part of an integrated combustion method and system, wherein photosynthetic organisms used within the photobioreactor are harvested from the photobioreactor, processed, and used as a fuel source for a combustion system like an electric power plant.

Claims

1. A photobioreactor system comprising:

at least one longitudinally extending photobioreactor unit comprising at least one photobioreactor section, the photobioreactor unit being constructed and arranged to carry a flow of a liquid medium comprising phototrophic organisms therein, the photobioreactor unit comprising;

at least one cover constructed and arranged to cover at least a substantial portion of the liquid medium within the photobioreactor unit and constructed and arranged to provide a gas headspace under the cover and above the liquid medium, the cover being capable of providing the gas headspace even when a gas pressure within the gas headspace of the photobioreactor unit is less than the atmospheric pressure surrounding the photobioreactor unit;

a first liquid inlet constructed and arranged to provide the liquid medium to the photobioreactor unit;

a first liquid outlet from which the liquid medium is removable from the photobioreactor unit;

a second liquid outlet positioned between the first liquid inlet and the first liquid outlet, from which the liquid medium is removable from the photobioreactor unit; and

a channel fluidically interconnecting the second liquid outlet to the photobioreactor unit at a position which is upstream of the second liquid outlet to enable return and recycle of the liquid medium within the photobioreactor unit.

2. The photobioreactor unit of claim 1, further comprising a second liquid inlet, different from the first liquid inlet, wherein the channel fluidically interconnects the second liquid outlet to the second liquid inlet.

3. The photobioreactor unit of claim 1, wherein the photobioreactor unit comprises a single, elongated photobioreactor section.

4. The photobioreactor unit of claim 1, wherein the photobioreactor unit comprises a plurality of interconnected photobioreactor sections.

5. The photobioreactor unit of claim 1, wherein the second liquid outlet fluidically interconnects the photobioreactor section to which it is associated to a different photobioreactor section.

6. The photobioreactor unit of claim 5, wherein the two fluidically interconnected photobioreactor sections have different functions.