CA2764291A1 - Low-cost integrated pond-photobioreactor - Google Patents
Low-cost integrated pond-photobioreactor Download PDFInfo
- Publication number
- CA2764291A1 CA2764291A1 CA 2764291 CA2764291A CA2764291A1 CA 2764291 A1 CA2764291 A1 CA 2764291A1 CA 2764291 CA2764291 CA 2764291 CA 2764291 A CA2764291 A CA 2764291A CA 2764291 A1 CA2764291 A1 CA 2764291A1
- Authority
- CA
- Canada
- Prior art keywords
- bioreactor
- water
- shape
- chamber
- integrated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M21/00—Bioreactors or fermenters specially adapted for specific uses
- C12M21/02—Photobioreactors
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M23/00—Constructional details, e.g. recesses, hinges
- C12M23/02—Form or structure of the vessel
- C12M23/04—Flat or tray type, drawers
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M23/00—Constructional details, e.g. recesses, hinges
- C12M23/02—Form or structure of the vessel
- C12M23/06—Tubular
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M23/00—Constructional details, e.g. recesses, hinges
- C12M23/22—Transparent or translucent parts
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M23/00—Constructional details, e.g. recesses, hinges
- C12M23/26—Constructional details, e.g. recesses, hinges flexible
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M23/00—Constructional details, e.g. recesses, hinges
- C12M23/48—Holding appliances; Racks; Supports
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Zoology (AREA)
- Organic Chemistry (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Chemical & Material Sciences (AREA)
- Wood Science & Technology (AREA)
- Genetics & Genomics (AREA)
- Biotechnology (AREA)
- Sustainable Development (AREA)
- Microbiology (AREA)
- Biochemistry (AREA)
- General Engineering & Computer Science (AREA)
- General Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Clinical Laboratory Science (AREA)
- Molecular Biology (AREA)
- Apparatus Associated With Microorganisms And Enzymes (AREA)
Abstract
A low-cost, durable, high surface-to-volume integrated translucent pond-photobioreactor (PBR) rapidly assembled by enclosing a particularly long semi-rigid, rollable fibreglass sheet into a repeating pattern of height-adjustable shape-sustaining supports. The elevated pond-PBR includes a low-cost temperature control, gas mixing and underside solar reflector. The entire system is fully collapsible.
Description
LOW-COST INTEGRATED POND¨PHOTOBIOREACTOR
FIELD OF THE INVENTION
The present invention relates to a bioreactor for production of biomass and more particularly to a low-cost, high surface-to-volume raceway-type pond that integrates features of photobioreactors such as transparency/translucency from all directions, closed environment, efficiency in the mixing of gases and temperature control.
BACKGROUND OF THE INVENTION
The current energy crisis has prompted interest in alternative energy, bringing a great deal of attention to the production of algae biofuels; beyond biofuels, commercial algae farming is also important to medicine, food, chemicals, aquaculture and production of feedstocks.
One major obstacle to the production of biofuels is the commercial scale-up for mass culture of algae and the high cost associated to such a culture.
The vast number of different bioreactor concepts is testimony that the best algal farming bioreactors are still to be found. Most bioreactor designs are not suitable for commercial use due to cost and scale-up problems. In contrast to bioreactors, pond technologies are commercially viable today, but have well-established problems of their own. Integrated technologies might provide the control offered through closed bioreactors and the scalability afforded by open ponds.
To appreciate the value of attempts made and of associated prior art, a short review of recent studies and related publications is presented:
According to Mario R. Tredici: "Outdoors, under full sunlight, the photosynthetic efficiency drops to one tenth-one fifth of the values observed at low irradiances. The major causes for this inefficiency are the light saturation effect (LSE) and photoinhibition, phenomena that strongly limit the growth of microalgae in outdoor culture, although these because of the high cell density, are light-limited.
The main problem is that photosynthetic apparatus of phototrophs saturates at low irradiances and that, at irradiances above saturation, the absorbed photons are used inefficiently and may cause cell injury. Several strategies to overcome the LSE and photoinhibition have been proposed, based on engineering (light dilution, ultra high cell density culture, high turbulence), physiologic (photoacclimation, nutrient deprivation) or genetic.. ."
(Tredici M. R. (2004) Mass production of microalgae: photobioreactors. In Richmond A
(ed.), Handbook of Microalgae Culture. Blackwell Publishing, Oxford (UK), pp 178-214.
Dimanshteyn taught in US Pat. 7,824,904 that photobioreactors generally consist of a container containing a liquid growth medium that is exposed to a light source.
However, the configuration of the photobioreactor often prevents the light from penetrating more than a few centimeters from the surface of the liquid. This problem reduces the efficiency of the photobioreactor, and was recognized in "Solar Lightning for Growth of Algae in a Photobioreactor" published by the Oak Ridge National Lab and Ohio University: Light delivery and distribution is the principle obstacle to using commercial-scale photobioreactors for algae production. In horizontal cultivator systems, light penetrates the suspension only to 5 cm leaving most of the algae in darkness.
As described in Healthy Algae, Fraunhofer Magazine, January 2002, "Algae are a very undemanding life form--they only need water, CO2, nutrients and sunlight.
However, providing sufficient sunlight can be a problem in large scale facilities. "As the algae at the surface absorb the light, it does not penetrate to a depth of more than a few millimeters. The organism inside the unit gets no light and cannot grow,"
explains Walter Troesch, who has been cultivating algae for years. "One of the problems with growing algae in any kind of pond is that only in the top 1-4" or so of the pond receives sufficient solar radiation for the algae to grow. In effect, this means that the ability of a pond to grow algae is limited by its surface area, not by its volume."
In summary, "the ability of a pond to grow algae is limited by its surface area, not by its volume."Therefore limitation in prior art are examined in consideration of the above findings.
FIELD OF THE INVENTION
The present invention relates to a bioreactor for production of biomass and more particularly to a low-cost, high surface-to-volume raceway-type pond that integrates features of photobioreactors such as transparency/translucency from all directions, closed environment, efficiency in the mixing of gases and temperature control.
BACKGROUND OF THE INVENTION
The current energy crisis has prompted interest in alternative energy, bringing a great deal of attention to the production of algae biofuels; beyond biofuels, commercial algae farming is also important to medicine, food, chemicals, aquaculture and production of feedstocks.
One major obstacle to the production of biofuels is the commercial scale-up for mass culture of algae and the high cost associated to such a culture.
The vast number of different bioreactor concepts is testimony that the best algal farming bioreactors are still to be found. Most bioreactor designs are not suitable for commercial use due to cost and scale-up problems. In contrast to bioreactors, pond technologies are commercially viable today, but have well-established problems of their own. Integrated technologies might provide the control offered through closed bioreactors and the scalability afforded by open ponds.
To appreciate the value of attempts made and of associated prior art, a short review of recent studies and related publications is presented:
According to Mario R. Tredici: "Outdoors, under full sunlight, the photosynthetic efficiency drops to one tenth-one fifth of the values observed at low irradiances. The major causes for this inefficiency are the light saturation effect (LSE) and photoinhibition, phenomena that strongly limit the growth of microalgae in outdoor culture, although these because of the high cell density, are light-limited.
The main problem is that photosynthetic apparatus of phototrophs saturates at low irradiances and that, at irradiances above saturation, the absorbed photons are used inefficiently and may cause cell injury. Several strategies to overcome the LSE and photoinhibition have been proposed, based on engineering (light dilution, ultra high cell density culture, high turbulence), physiologic (photoacclimation, nutrient deprivation) or genetic.. ."
(Tredici M. R. (2004) Mass production of microalgae: photobioreactors. In Richmond A
(ed.), Handbook of Microalgae Culture. Blackwell Publishing, Oxford (UK), pp 178-214.
Dimanshteyn taught in US Pat. 7,824,904 that photobioreactors generally consist of a container containing a liquid growth medium that is exposed to a light source.
However, the configuration of the photobioreactor often prevents the light from penetrating more than a few centimeters from the surface of the liquid. This problem reduces the efficiency of the photobioreactor, and was recognized in "Solar Lightning for Growth of Algae in a Photobioreactor" published by the Oak Ridge National Lab and Ohio University: Light delivery and distribution is the principle obstacle to using commercial-scale photobioreactors for algae production. In horizontal cultivator systems, light penetrates the suspension only to 5 cm leaving most of the algae in darkness.
As described in Healthy Algae, Fraunhofer Magazine, January 2002, "Algae are a very undemanding life form--they only need water, CO2, nutrients and sunlight.
However, providing sufficient sunlight can be a problem in large scale facilities. "As the algae at the surface absorb the light, it does not penetrate to a depth of more than a few millimeters. The organism inside the unit gets no light and cannot grow,"
explains Walter Troesch, who has been cultivating algae for years. "One of the problems with growing algae in any kind of pond is that only in the top 1-4" or so of the pond receives sufficient solar radiation for the algae to grow. In effect, this means that the ability of a pond to grow algae is limited by its surface area, not by its volume."
In summary, "the ability of a pond to grow algae is limited by its surface area, not by its volume."Therefore limitation in prior art are examined in consideration of the above findings.
Traditional procedures employed for culturing autotrophic organisms have involved the use of shallow open ponds or open channels exposed to sunlight. Not surprisingly this comparatively crude method has proved impracticable for production of pure high grade products because of such problems as invasion by hostile species (sometimes producing dangerous toxins), other pollution (such as dust), difficulty in the control of such variables as nutrient ratios, temperature and pH, intrinsically low yield because of escape of carbon dioxide to the atmosphere and inefficient use of light to illuminate only the top portion of the biomass.
Somewhat more sophisticated attempts have involved the use of horizontally disposed large diameter transparent plastics tubes for biomass production. The problems of such a system include the low density of biomass in the liquid within the tubes, coating of the pipes by algae due to low velocity flow passing through, thus reducing transparency, overheating in summer weather, high land usage and high energy input to displace large amount of over diluted water.
Now, looking closely at receptacles dislosed in prior art and more particularly for potential use as low-cost raceway-type pond or photo bioreactor, a number of inventions are examined.
U.S. Pat. No. 7,069,875 to Warecki ("Warecki") discloses a large and low cost portable raceway or vessel for holding flowable materials. The vessel has a body formed of an elongate rot table sheet of buoyant material that when assembled into an upwardly concave vessel has bulkheads at its ends to give it its half rounded shape.
The large vessel is self-supporting in both water and land. The Warecki vessel suffers from a number of limitations. Joining of parts such as bulkheads to the body of the vessel requires welding, chemical bonding, and-or mechanical fastening. Also, to maintain the shape of the pond, bulkhead bow frames must be positioned inside the vessel, dividing the space into closed compartments that are fastened mechanically or chemically to the body, although some unsecured movable compartments are used.
Somewhat more sophisticated attempts have involved the use of horizontally disposed large diameter transparent plastics tubes for biomass production. The problems of such a system include the low density of biomass in the liquid within the tubes, coating of the pipes by algae due to low velocity flow passing through, thus reducing transparency, overheating in summer weather, high land usage and high energy input to displace large amount of over diluted water.
Now, looking closely at receptacles dislosed in prior art and more particularly for potential use as low-cost raceway-type pond or photo bioreactor, a number of inventions are examined.
U.S. Pat. No. 7,069,875 to Warecki ("Warecki") discloses a large and low cost portable raceway or vessel for holding flowable materials. The vessel has a body formed of an elongate rot table sheet of buoyant material that when assembled into an upwardly concave vessel has bulkheads at its ends to give it its half rounded shape.
The large vessel is self-supporting in both water and land. The Warecki vessel suffers from a number of limitations. Joining of parts such as bulkheads to the body of the vessel requires welding, chemical bonding, and-or mechanical fastening. Also, to maintain the shape of the pond, bulkhead bow frames must be positioned inside the vessel, dividing the space into closed compartments that are fastened mechanically or chemically to the body, although some unsecured movable compartments are used.
World Patent No.W02011016735 to Dalrymple discloses an erectable trough for animal feed. The plastic sheet disclosed by Darlymple is bent into a U-shaped trough with opposite side walls being supported upright by tension wires through perforations in the side walls. As disclosed, the trough is not waterproof and not suitable for a closed raceway.
U.S. Pat. No. 5,846,816 to Forth ("Forth") discloses a biomass production apparatus includes a transparent chamber which has an inverted, triangular cross-section.
Although the Forth bioreactor promotes the growth of biological matter, it contradicts the principles extensively tested by Tredici, Fraunhofer and National Labs that assert the need to maximize exposed surface area relative to the volume displaced.
Furthermore, the disclosed chamber is expensive to manufacture. Finally, the constant circulation of the liquid required by Forth interfers with the growth of some types of biological matter.
For instance, fully differentiated aquatic plants from the lemnaceae or "duckweed"
family are fresh-water plants that grow best on the surface of the water. Such surface growing plants typically prefer relatively still water to support and promote optimal growth.
Often, the importance of the surface area directly exposed to sunlight and which can benefit from the photosynthesis process has been overlooked in prior art.
Consequently, many inventions have paid more attention to the volume of water and of the over diluted algal suspension being displaced than the actual available amount of photon per square meter available to that algal solution. This resulting low-efficiencies have lead to the necessity of oversizing algae farming facilities and consequently to high costs in investment, operations and energy.
To overcome limitations of prior art, the present invention provides an improved closed raceway-type pond that further integrates positive elements found in photobioreactors such as transparency/translucency from all directions including from underside, closed environment, high illuminated surface-to-volume ratio, efficient gas mixing and low-cost cooling system.
U.S. Pat. No. 5,846,816 to Forth ("Forth") discloses a biomass production apparatus includes a transparent chamber which has an inverted, triangular cross-section.
Although the Forth bioreactor promotes the growth of biological matter, it contradicts the principles extensively tested by Tredici, Fraunhofer and National Labs that assert the need to maximize exposed surface area relative to the volume displaced.
Furthermore, the disclosed chamber is expensive to manufacture. Finally, the constant circulation of the liquid required by Forth interfers with the growth of some types of biological matter.
For instance, fully differentiated aquatic plants from the lemnaceae or "duckweed"
family are fresh-water plants that grow best on the surface of the water. Such surface growing plants typically prefer relatively still water to support and promote optimal growth.
Often, the importance of the surface area directly exposed to sunlight and which can benefit from the photosynthesis process has been overlooked in prior art.
Consequently, many inventions have paid more attention to the volume of water and of the over diluted algal suspension being displaced than the actual available amount of photon per square meter available to that algal solution. This resulting low-efficiencies have lead to the necessity of oversizing algae farming facilities and consequently to high costs in investment, operations and energy.
To overcome limitations of prior art, the present invention provides an improved closed raceway-type pond that further integrates positive elements found in photobioreactors such as transparency/translucency from all directions including from underside, closed environment, high illuminated surface-to-volume ratio, efficient gas mixing and low-cost cooling system.
SUMMARY OF THE INVENTION
The present invention discloses a low-cost integrated pond-photobioreactor that combines the control of microalgae culture typical to photobioreactors and the scalability provided by ponds. More particularly, the invention teaches a low-cost, thin, extra long, transparent/translucent modular integrated pond-photobioreactor that maximizes exposure to sunlight with a high surface-to-volume ratio, eliminates water leakage problems, is easy to manufacture and rapid to assemble. Furthermore, the invention discloses a particularly long bioreactor chamber that may collapse into a roll;
such an advantage reduces substantially transport, storage and installation costs.
The terms "bioreactor chamber", "bioreactor", "chamber" or "AlgaReactor(TM) (a Trademark owned by S. Mottahedeh) are equivalent and are interchangeably used throughout this invention; they all refer to the "integrated pond¨photobioreactor" of this invention unless specified otherwise.
In one embodiment of the invention, the bioreactor includes a low-cost temperature control provided by a water jacket having a low demand of water and energy to operate.
In another embodiment of the invention, cooling is provided by a passive low-cost evaporative system that cools a heat pipe in fluid communication with the bioreactor chamber or with one or two water tanks attached to the bioreactor.
The bioreactor is elevated above ground capturing light from all directions, including extra light from a solar reflector or reflective material placed on the ground, exposing further the bioreactor underside to reflected light. The bioreactor may also include an artificial light source such as LED. Furthermore, in one embodiment of the invention, an efficient low-cost gas mixing sparger system is in fluid communication with the bioreactor chamber. In another embodiment, a horizontal pond-like L-shaped or T-shape bioreactor chamber is provided with a U-shape recess, like a water pocket that enhances gas mixing.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of a roll of plastic sheet being shaped into a pond-shaped bioreactor chamber.
FIG. 2 is a perspective view of an open bioreactor with an external removable cover.
FIG. 3 is a perspective view of a bioreactor incorporating an integral cover.
FIG. 4 is a perspective view of a bioreactor chamber shaped by a C-shaped bracket FIG. 5 is a perspective view of a closed raceway-type integrated pond-photobioreactor FIG. 6 is a cutaway view of a plastic bag with an integral sparger tube.
FIG. 7 is a perspective view of a bioreactor chamber incorporating an overlapping cover.
FIG. 8 is a perspective view of a bioreactor supported by buoys with a plastic sleeve inside.
FIG. 9 is a cutaway view of a double-wall bioreactor chamber having a water jacket.
FIG. 10 is a cutaway view of an L-shape bioreactor with a flat base and a side water pocket.
FIG. 11 is a perspective view of an L-shape bioreactor chamber with an alternate support means.
FIG. 12 is a perspective view of a T-shape support.
FIG. 13 is a perspective view of a U-shape water tank with an internal spiral-shape gas mixer.
FIG. 14is a perspective view of a U-shape tank with an external linear-shape gas mixer with a cooling system.
FIG. 15 is a close-up view of the cooling system of FIG. 14 with a ventilator.
DETAILED DESCRIPTION OF THE INVENTION
This invention combines the scalability and cost-effectiveness offered by open ponds with the biomass growth control provided by photobioreactors such as providing a closed growth environment, a high surface-to-volume light exposure ratio, light exposure from all directions, efficient gas mixing and a low-cost cooling system.
Therefore the resulting integrated pond-photobioreactor 10 of the present invention offers advantages from both systems while reducing substantially costs of both systems.
FIGS. 1 and 2 show a preferred embodiment of the invention wherein an open-top bioreactor chamber 10 is created by enclosing a thin, extra long, bendable, transparent/translucent plastic sheet 12 made of a semi-rigid material such as fibreglass into a repeating pattern of shape-sustaining supports 80, such as a height-adjustable delta-shape support 82.
Enclosing a plastic sheet 12 into a shape-sustaining support such as in a cavity 87 (FIG. 1) or a bracket 110 (FIG. 4) transforms readily a plastic sheet 12 into a semi-tubular thin-shell structure which results in the stiffening of the sheet borders making it more resistant to bending stresses. As a result of this tubular-shape configuration, the bending stresses on the plastic sheet 12 convert largely into compression and tensile stresses which are well resisted by semi-rigid plastics and particularly by fibreglass.
Consequently, an elevated C-shaped bioreactor chamber 10 may be spanned or suspended at a longer distance than a typical flat sheet 12. This translates into longer spans that may be projected between load-bearing or shape-sustaining supports than a typical non-stiffened sheet 12; such an advantage reduces costs and makes commercial scale-up of biomass production more affordable.
A bioreactor 10 may be preferably made of a material such as fiberglass also known as fiber reinforced plastic (FRP). Other transparent/translucent materials may also be used such as , but not limited to, low density polyethylene (LDPE), high-density polyethylene (HDPE), hard acrylic (PMMA), polyvinyl chloride (PVC), polycarbonate (PC), composite plastics, and a combination thereof.
The bioreactor chamber 10 of the invention may be compacted into a roll 26, thus making the bioreactor 10 reducible in length from a wide, extra long bioreactor chamber into a compacted roll 26 which reduces substantially transport, storage and installation costs. Furthermore, a plastic sheet 10 such as fiberglass offers other advantages such durability and ease of repair and maintenance. A fiberglass sheet 12 typically may last as long as 25 years and more, making return on investment substantially affordable.
As illustrated in FIGS. 1, 2 and 3, both shape and size of the inner perimeter of cavity 87 dictate the final shape that a plastic sheet 12 of a given width 82 will adopt, when enclosed in a shape-sustaining support 80. For example, when a standard width sheet 12 is enclosed in cavity 87, an open-top bioreactor chamber 10 may be created;
whereas when an extra-wide plastic sheet 12 (or multiple sheets adhered side-by-side to each other) is inserted in a same size cavity 87, the resulting bioreactor chamber 10 shape may now incorporate its own cover 50 such as shown in FIG. 3.
Furthermore, variation of the shape of cavity 87 positioned in the upper portion 82 of a shape-sustaining support 80 or 88 (FIGS. 11, 12) enables the creation of a wide range of shapes such as, but not limited to, an L-shape bioreactor chamber 10 provided with a water pocket 13 that increases residence time of mixing gases with water. In the same manner, placing a U-shaped water pocket 13 in the middle of the flat base portion of a chamber 10 results in a T-shape bioreactor chamber (FIG. 12). The same principle applies to other shapes and sizes of cavities 87 cooperating with different width of plastic sheets 12. For example, an M-shape bioreactor 10 (not shown) may have three U-shape recesses. An oblique bioreactor 10 resembles the shape of an inclined photobioreactor panel (not shown).
As disclosed earlier, adhering overlapping borders of multiple parallel plastic sheets 12 side-by-side, by tape means or by chemical means, enables to create extra wide plastic sheets 12. Equally, by adhering together multiple non-parallel plastic sheets 12 and enclosing such variable-size sheets 12 in cavities 87 where cavity sizes or shapes may also vary relative to previous cavities 87, enables to gradually increase or decrease width, depth and shape of a bioreactor 10 along its length. For example an L-shape bioreactor 10 may gradually take on a different shape such as a flat base bioreactor 10 and finish into a cylindrical-shape or an inclined-shape bioreactor chamber 10 (not shown). Often, microalgae innoculation is first done in closed photobioreactors before the resulting culture is transferred into open or closed ponds for mass culture. The present bioreactor 10 of the invention provides a variation of shapes that enhance both the control needed in photobioreactors and the scalability desired by ponds. Furthermore, this controlled variation of shapes is achieved at low-cost.
In another embodiment of the invention, shape-sustaining supports take on the shape of C-shaped brackets 110 as shown in FIGS. 4, 7, 8, 9 and 10. AC-shaped bracket 110 is configured with a flat base portion flanked between two curved sidewalls;
each sidewall front edge being provided with a reverse bend 112 and 114, also referred to as hooks 112 and 114.
FIGS. 8 and 9 illustrate two opposing edges of sheet 12 meeting overlappingly each other. To further provide a tight sealing between said opposing edges of sheet (cooperating with hooks 112 and 114), a long extruded plastic profile 70, such as an H-type extruded profile 70 may be provided to seal opposite borders of said plastic sheet 12.
In all embodiments of this invention, bioreactor chamber 10 is elevated above ground exposing chamber 10 to sunlight from all directions, including from underside.
To enhance further this beneficiary effect essential to the photosynthesis process, a solar reflective material 120 such as a reflective film 120, paint or a reflective mineral 120 my be placed under chamber 10; the general configuration of a reflective film 120, of a painted ground or of any reflective minerals 120 deposited over a ground surface may be oriented with an angle or a curve, or may be simply laid flat over the ground.
In the preferred embodiments of the invention, the C-shaped plastic sheet 12 is combined with an external removable cover 50 for creating a closed chamber 10.
A
removable cover 50 may readily be removed, making access, cleaning and maintenance of the bioreactor chamber 10 easy. As shown in FIG. 2, borders of cover 50 may be simply slided inside the upper portion of the repeating pattern of shape-sustaining supports 82. Cover 50 may also be made of a thin, rollable, transparent/translucent plastic sheet 12 such as a thinner or thicker fiberglass material that may incorporate its own portholes 52 (FIG.4) and devices that promote biomass growth. This arrangement provides a reliable sealing means of cover 50 over sheet 12 throughout the length of bioreactor chamber 10. Cover 50 may also be made of more common, low-cost, disposable, plastic films.
FIGS. 1, 2, 3 and further illustrate how a height-adjustable delta-shape angle-variable front panels 84 and back panel 86, or vertical boards 88 and 89 (FIG.
11) transfer weight of an elevated bioreactor 10 across the full width of the bioreactor 10 directly to the ground. This distribution of weight allows for panels 84, 86 and/or for boards 88, 89 to use low-cost construction materials such as wood, plastic-lumber, fiberglass, fiber-cement, clay, magnesium oxide, gypsum, or a combination thereof.
Boards and panels 82 may have a natural white color, or may be painted or covered with a white glossy coating or a reflective material.
Panels 84, 86 and boards 88, 89 perform multiple functions such as sustaining a desired configuration such as C-shape, L-shape, T-shape, U-shape, M-shape, or an oblique-shape configuration throughout the length of plastic sheet 12; they also act as light reflectors 120 and as height adjustors of shape-sustaining supports 80 to enable light exposure to underside of transparent/translucent plastic sheet 12.
To adjust the level of a bioreactor chamber 10 so as to maintain a substantially constant layer of water and biomass along the length of a bioreactor chamber 10, various height-adjustable means 80 are configured to cooperate with selected types of shape-sustaining supports. FIGS. 1, 2, 3, 5 and 11 illustrate a delta-shape support 80 wherein height adjustment is provided by varying the angle of a first panel 86 to change the angle of a second panel 84, which in turn results in height variation of chamber 10.
The fixation of panels 84 and 86 in a final position may be achieved via a system of tongues and grooves in panels 84 and 86, via screws or nylon ties or fastening means of the like.
FIG. 8 shows inflatable buoys 400 that may be pumped or deflated to adjust height of bioreactor chamber 10. FIGS. 9 and 10 illustrate a scaffold-type height-adjustable structure 80 that includes a horizontal bar 81 that may be affixed at a desirable height on two vertical pipes or poles 83 and 84. FIGS. 11 and 12 illustrate another type of height-adjustable structure 80 wherein by two vertical interlocking flat panels 88 and 89 cooperate together via multiple rails positioned at different heights. In another embodiment, panels 88 and 89 may slide into each other to vary height. In yet another embodiment, shape-sustaining supports may slide between two vertical rails (not shown) or are provided with cooperating movable wedges to vary height.
Traditionally, fiber reinforced plastic (FRP) sheets also referred to in this invention as "fiberglass" or plastic sheet 12, may be manufactured and supplied with different thicknesses. The semi-rigid transparent/translucent fibreglass (FRP) sheet 12 referred to in this invention relates to bendable rolls 26 of FRP sheets varying from 0.5mm to 1.2mm thick, 15 or 30 m long. Typically, thicker FRP sheets are too stiff to be reduced into rolls 26. Standard width of FRP sheets vary from 0.6m, lm to 1.2m and can also be custom-made to 1.6m wide. However, FRP sheets of various thicknesses can be readily adhered together establishing any desired width as necessary.
Plastic sheet 12 of bioreactor chamber 10 or of cover 50 (FIG. 4) may further include by attachment means or by embedding into the sheet 12 during the manufacturing process devices that promote, detect or monitor biomass growth such as, but not limited to, flexible wires, sensors (60), monitors, detectors, connectors, light emitting diode (LED) 40, computer chips, optical sensors, Bluetooth (RE) short-range connections (Bluetooth is a Trademark owned by Bluetooth(R) SIG), photovoltaic cells, batteries, microplate reader, and a combination thereof.
Also, various devices may be attached along borders of sheet 10. These may include hangers 30 (FIG. 4) for holding an air sparger system 28, LED tapes or ropes, instruments and other devices that promote, detect or monitor biomass growth as disclosed above. Said devices may also be attached or embedded into the elongate sealable extruded plastic profile 70 (FIG. 7) that joins opposing sheet edges 12 in closable bioreactor chambers 10.
FIG. 8 shows a bioreactor 10 positionable over a water surface. Bioreactor chamber 10 may float directly above a water surface, or may be supported by buoys 400 or by other floating systems 400. As an example, a closed bioreactor chamber 10 may be floated over a water channel, a dysfunctional raceway-type pond, a polluted water surface, a lake, a swampy land where isolating of a bioreactor content from an outside negative environment is required, and vice-versa.
Positioning a floating reflective film 120, such as foil bubble-back insulation-type reflective film on the underside of a floating bioreactor 10, provides additional sunlight to the bioreactor 10 in addition to the direct and sunlight sunlight that the system may receive. Buoyancy units 400 may also be inflatable; rising or lowering bioreactor 10 may help discharge some of the semi-liquid content 18 present in bioreactor chamber 10 or positioned in a plastic bag 20 or sleeve 20 inserted in bioreactor 10. Rising and lowering bioreactor 10 may also be used to generate waves or vibrations to create agitation in the liquid content 18 of bioreactor 10.
FIG. 6 also shows a plastic bag 20 being used as a liner inside bioreactor 10.
Plastic bag 20 may be sterilized by gamma ray or by other means to provide a sterile transparent/translucent environment for more sensitive strains of microalgae.
Water or other liquids may be also circulated around plastic bag 20 to control temperature of the bag content. Also, lining bioeractor 10 with a plastic bag 20 reduces cleaning and maintenance needs of bioreactor 10. Liner 20 may include an internal gas sparger 28 made of a thin plastic disposable material such as used for drip irrigation systems, while at the same time reducing cleaning and maintenance problems associated with bioreactors 10. Sparger tube 28 may also be made of a gas-permeable material such as, but not limited to, rubber particles for delivery of air and carbon dioxide inside plastic bag 20.
Bioreactor 10, may also be provided with a dewatering system. To dewater the biomass, plastic sleeve 20 is provided with an upper transparent/translucent film 310, and a bottom osmosis membrane 320. Plastic sleeve 20 is partially filled with water and a biomass suspension 18. Sleeve 20 is made to float in the bioreactor 10 over a fluid of higher solute concentration than it own fluid content such as, but not limited to, sea water. It is known that any liquid of lower solute concentration flows through an osmosis membrane to a liquid of higher solute concentration to seek equilibrium. This flow effect causes dehydration of biomass 18.
In another embodiment of the invention (FIG. 8), dewatering of the biomass may be achieved by providing a sleeve 20 made entirely of an osmosis membrane and partially filled with salt water inside said sleeve 20. Water content in diluted biomass 16 present in bioreactor 10 permeates through the osmosis membrane 320 of sleeve 20 and flows towards the higher solute concentration present inside sleeve 20 causing dehydration of biomass in bioreactor 10.
As an example of how multiple rows of bioreactor chambers 10 may cooperate together, FIG. 5 shows an integrated raceway-type pond-photobioreactor 10 wherein ends of two rows of bioreactor chambers 10 are connected via a U-shaped water tank 500. Other open or closed forms of layouts of bioreactor chambers 10 in fluid communication with each other are provided, in the same manner, using water tanks 500.
Extension of length of a bioreactor chamber 10 is simply achieved by adhering overlappingly ends of two adjacent sheets 12. Preferably, a shape-sustaining support 80 may be located at a position where the two chambers 10 are joined together.
FIG. 9 and 10 show a bioreactor 10 incorporating a first embodiment of a temperature control system through a water jacket created created by a hollow spacer 24 placed between two layers of thin plastic sheets 12 and 22. Both plastic sheet layers 12 and 22 are inserted in a repeating pattern of shape-sustaining support 80 or in a repeating pattern of C-shaped bracket 110.
FIGS. 9 and 10 also show an elevated scaffold-type U-shaped metal structure 80 that supports bioreactor 10; these elevated U-shaped structures 80 may comprise a horizontal bar 81 which ends are supported by two vertical poles or pipes 83 and 85.
The height and angle of horizontal bar 81 are adjustable for rapid adjustment of the bioreactor chamber 10 to keep a substantially constant water depth along the length of the extra long chamber 10. In this type of modular structure 80, multiple scaffolds 80 may also be stacked above each other or sideways to reduce land usage while still allowing sunlight to penetrate from underside of bioreactor 10.
FIG. 10 shows another embodiment of bioreactor 10 having an L-shape configuration. This L-shaped bioreactor 10 may also include an integral water jacket located around the water pocket 13; as disclosed earlier, the water jacket of the invention is made of a second layer of plastic sheet 22 laid over an original layer of plastic sheet 12 with a hollow spacer 24 placed in-between them.
In the preferred embodiments of the invention, the two ends of an elongate bioreactor 10 are in fluid communication with a water tank 500. The elongate chamber may also be closed by two bulkheads (not shown). A bulkhead is best made of a flat plate-shaped body configured with substantially a similar cross-sectional dimension than a chamber 10 surrounded by soft seal affixed to the bulkhead contour.
Bulkheads may be also placed anywhere and at any time inside a bioreactor chamber 10 to close or isolate a section of a chamber 10.
In an embodiment of the invention as shown in FIG. 13, the U-shaped water tank 500 may also include a mixing system 520 comprising a spiral-shaped tube 522, submerged in water tank 500 with a substantially smaller diameter gas-permeable tube 28 partially inserted in said spiral-shaped tube 522 to supply air and carbon dioxide;
mixing of gases in water tank 500 or via an attachment underneath bioreactor chamber 10 may also be achieved by a pump or injector means that circulates culture;
the pump may also include a thermocontrol system. Bubbles generated by gas-permeable tube 28, after mixing with water in the long spiral-shaped pipe 522 exit parallel to the water and biomass present in chamber 10, causing both agitation and a forward motion in chamber 10.
FIG. 14 shows a linear gas mixing device 520 comprising of two long straight pipes 532 and 534; at least one pipe 532 has a larger diameter. Pipes 532 and 534 are connected together outside water tank 500; optionally, a small portion (530) of larger pipe 532 may be placed inside tank 500 with its exit 530 positioned at a more elevated location than entry of pipe 530. However, this is not required when other methods of water and biomass circulation is provided to create agitation in bioreactor chamber 10.
In this linear mixing device 520 (wihout exit pipe 530 in tank 500), the two pipes 532 and 534 are both connected to the bottom of tank 500 and are always filled with water and biomass suspension. A smaller gas-permeable tube 28 partially inserted inside the bigger pipe 532, supplies air and carbon dioxide; gas bubbles generated by tube 28 inside pipe 532 create a natural forward flow in pipe 532 and consequently causes a suction effect in pipe 534, both actions causing water circulation at the bottom of tank 500 which further enhances mixing of gases with water and biomass.
FIGS. 14 and 15 also illustrate how an evaporative water cooling system 600 of the invention may cool a U-shaped water tank 500 attached to bioreactor 10 or may cool directly a bioreactor chamber 10 via a connection attached anywhere underneath a bioreactor chamber 10. The water cooling system 600 may be in fluid communication directly with or through a heat exchanger (not shown) with a U-shaped tank 500.
As illustrated in FIG. 15, the evaporative cooling system 600 comprises an elongate heat pipe 534 such as a metal pipe, containing a circulating water in fluid communication with the bottom of bioreactor chamber 10; heat pipe 534 is surrounded by a layer of a porous material 620 such as, but not limited to, charcoal, expanded clay pebbles, evaporative wick, and porous materials of the like; the porous material 620 is contained inside a wire meshing; a drip watering system 622 is positioned above the porous material 622 and is continuously or automatically wetting the porous material 620; an elongate larger enclosure 720 surrounds the wire meshing; an air duct 710 one end is partially inserted inside larger enclosure 720 and other end is attached to an elevated wind turbine ventilator 700; the ventilator 700 creates an air draft in the larger enclosure 720 sucking air through the enclosure 720 and causing evaporation of moisture present in the porous material 620 which in turn creates a cooling effect of heat pipe 534. When the cooling system 600 operates in tandem with the gas mixing system 520 as shown in FIGS. 14 and 15, a natural water circulation is created in heat pipe 534, increasing the efficiency of both the low-cost mixing system and the low-cost cooling system of the invention.
In FIGS. 14 and 15, arrows represent fluid flows. WD represents the flow direction of drip water in pipe 622, A+C represents Air and Carbon dioxide flow in tube 28, W+B
represents flow of Water and Biomass. Similarly, W+B+A+C represents the flow of Water, Biomass mixed with Air and Carbon dioxide.
Agitation of biomass such as microalgae in bioreactor 10 may be achieved by a pump (not shown), a water wheel (not shown) or a wave generator (not shown).
In embodiments of the invention that require a sterile cultivation, when using an agitation equipment such as a water wheel or a wave generator, the agitation equipment is configured to maintain a degree of air-tightness that prevents any form of air contamination from outside.
Certain features of this invention may sometimes be used to advantage without a corresponding use of the other features. While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
The present invention discloses a low-cost integrated pond-photobioreactor that combines the control of microalgae culture typical to photobioreactors and the scalability provided by ponds. More particularly, the invention teaches a low-cost, thin, extra long, transparent/translucent modular integrated pond-photobioreactor that maximizes exposure to sunlight with a high surface-to-volume ratio, eliminates water leakage problems, is easy to manufacture and rapid to assemble. Furthermore, the invention discloses a particularly long bioreactor chamber that may collapse into a roll;
such an advantage reduces substantially transport, storage and installation costs.
The terms "bioreactor chamber", "bioreactor", "chamber" or "AlgaReactor(TM) (a Trademark owned by S. Mottahedeh) are equivalent and are interchangeably used throughout this invention; they all refer to the "integrated pond¨photobioreactor" of this invention unless specified otherwise.
In one embodiment of the invention, the bioreactor includes a low-cost temperature control provided by a water jacket having a low demand of water and energy to operate.
In another embodiment of the invention, cooling is provided by a passive low-cost evaporative system that cools a heat pipe in fluid communication with the bioreactor chamber or with one or two water tanks attached to the bioreactor.
The bioreactor is elevated above ground capturing light from all directions, including extra light from a solar reflector or reflective material placed on the ground, exposing further the bioreactor underside to reflected light. The bioreactor may also include an artificial light source such as LED. Furthermore, in one embodiment of the invention, an efficient low-cost gas mixing sparger system is in fluid communication with the bioreactor chamber. In another embodiment, a horizontal pond-like L-shaped or T-shape bioreactor chamber is provided with a U-shape recess, like a water pocket that enhances gas mixing.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of a roll of plastic sheet being shaped into a pond-shaped bioreactor chamber.
FIG. 2 is a perspective view of an open bioreactor with an external removable cover.
FIG. 3 is a perspective view of a bioreactor incorporating an integral cover.
FIG. 4 is a perspective view of a bioreactor chamber shaped by a C-shaped bracket FIG. 5 is a perspective view of a closed raceway-type integrated pond-photobioreactor FIG. 6 is a cutaway view of a plastic bag with an integral sparger tube.
FIG. 7 is a perspective view of a bioreactor chamber incorporating an overlapping cover.
FIG. 8 is a perspective view of a bioreactor supported by buoys with a plastic sleeve inside.
FIG. 9 is a cutaway view of a double-wall bioreactor chamber having a water jacket.
FIG. 10 is a cutaway view of an L-shape bioreactor with a flat base and a side water pocket.
FIG. 11 is a perspective view of an L-shape bioreactor chamber with an alternate support means.
FIG. 12 is a perspective view of a T-shape support.
FIG. 13 is a perspective view of a U-shape water tank with an internal spiral-shape gas mixer.
FIG. 14is a perspective view of a U-shape tank with an external linear-shape gas mixer with a cooling system.
FIG. 15 is a close-up view of the cooling system of FIG. 14 with a ventilator.
DETAILED DESCRIPTION OF THE INVENTION
This invention combines the scalability and cost-effectiveness offered by open ponds with the biomass growth control provided by photobioreactors such as providing a closed growth environment, a high surface-to-volume light exposure ratio, light exposure from all directions, efficient gas mixing and a low-cost cooling system.
Therefore the resulting integrated pond-photobioreactor 10 of the present invention offers advantages from both systems while reducing substantially costs of both systems.
FIGS. 1 and 2 show a preferred embodiment of the invention wherein an open-top bioreactor chamber 10 is created by enclosing a thin, extra long, bendable, transparent/translucent plastic sheet 12 made of a semi-rigid material such as fibreglass into a repeating pattern of shape-sustaining supports 80, such as a height-adjustable delta-shape support 82.
Enclosing a plastic sheet 12 into a shape-sustaining support such as in a cavity 87 (FIG. 1) or a bracket 110 (FIG. 4) transforms readily a plastic sheet 12 into a semi-tubular thin-shell structure which results in the stiffening of the sheet borders making it more resistant to bending stresses. As a result of this tubular-shape configuration, the bending stresses on the plastic sheet 12 convert largely into compression and tensile stresses which are well resisted by semi-rigid plastics and particularly by fibreglass.
Consequently, an elevated C-shaped bioreactor chamber 10 may be spanned or suspended at a longer distance than a typical flat sheet 12. This translates into longer spans that may be projected between load-bearing or shape-sustaining supports than a typical non-stiffened sheet 12; such an advantage reduces costs and makes commercial scale-up of biomass production more affordable.
A bioreactor 10 may be preferably made of a material such as fiberglass also known as fiber reinforced plastic (FRP). Other transparent/translucent materials may also be used such as , but not limited to, low density polyethylene (LDPE), high-density polyethylene (HDPE), hard acrylic (PMMA), polyvinyl chloride (PVC), polycarbonate (PC), composite plastics, and a combination thereof.
The bioreactor chamber 10 of the invention may be compacted into a roll 26, thus making the bioreactor 10 reducible in length from a wide, extra long bioreactor chamber into a compacted roll 26 which reduces substantially transport, storage and installation costs. Furthermore, a plastic sheet 10 such as fiberglass offers other advantages such durability and ease of repair and maintenance. A fiberglass sheet 12 typically may last as long as 25 years and more, making return on investment substantially affordable.
As illustrated in FIGS. 1, 2 and 3, both shape and size of the inner perimeter of cavity 87 dictate the final shape that a plastic sheet 12 of a given width 82 will adopt, when enclosed in a shape-sustaining support 80. For example, when a standard width sheet 12 is enclosed in cavity 87, an open-top bioreactor chamber 10 may be created;
whereas when an extra-wide plastic sheet 12 (or multiple sheets adhered side-by-side to each other) is inserted in a same size cavity 87, the resulting bioreactor chamber 10 shape may now incorporate its own cover 50 such as shown in FIG. 3.
Furthermore, variation of the shape of cavity 87 positioned in the upper portion 82 of a shape-sustaining support 80 or 88 (FIGS. 11, 12) enables the creation of a wide range of shapes such as, but not limited to, an L-shape bioreactor chamber 10 provided with a water pocket 13 that increases residence time of mixing gases with water. In the same manner, placing a U-shaped water pocket 13 in the middle of the flat base portion of a chamber 10 results in a T-shape bioreactor chamber (FIG. 12). The same principle applies to other shapes and sizes of cavities 87 cooperating with different width of plastic sheets 12. For example, an M-shape bioreactor 10 (not shown) may have three U-shape recesses. An oblique bioreactor 10 resembles the shape of an inclined photobioreactor panel (not shown).
As disclosed earlier, adhering overlapping borders of multiple parallel plastic sheets 12 side-by-side, by tape means or by chemical means, enables to create extra wide plastic sheets 12. Equally, by adhering together multiple non-parallel plastic sheets 12 and enclosing such variable-size sheets 12 in cavities 87 where cavity sizes or shapes may also vary relative to previous cavities 87, enables to gradually increase or decrease width, depth and shape of a bioreactor 10 along its length. For example an L-shape bioreactor 10 may gradually take on a different shape such as a flat base bioreactor 10 and finish into a cylindrical-shape or an inclined-shape bioreactor chamber 10 (not shown). Often, microalgae innoculation is first done in closed photobioreactors before the resulting culture is transferred into open or closed ponds for mass culture. The present bioreactor 10 of the invention provides a variation of shapes that enhance both the control needed in photobioreactors and the scalability desired by ponds. Furthermore, this controlled variation of shapes is achieved at low-cost.
In another embodiment of the invention, shape-sustaining supports take on the shape of C-shaped brackets 110 as shown in FIGS. 4, 7, 8, 9 and 10. AC-shaped bracket 110 is configured with a flat base portion flanked between two curved sidewalls;
each sidewall front edge being provided with a reverse bend 112 and 114, also referred to as hooks 112 and 114.
FIGS. 8 and 9 illustrate two opposing edges of sheet 12 meeting overlappingly each other. To further provide a tight sealing between said opposing edges of sheet (cooperating with hooks 112 and 114), a long extruded plastic profile 70, such as an H-type extruded profile 70 may be provided to seal opposite borders of said plastic sheet 12.
In all embodiments of this invention, bioreactor chamber 10 is elevated above ground exposing chamber 10 to sunlight from all directions, including from underside.
To enhance further this beneficiary effect essential to the photosynthesis process, a solar reflective material 120 such as a reflective film 120, paint or a reflective mineral 120 my be placed under chamber 10; the general configuration of a reflective film 120, of a painted ground or of any reflective minerals 120 deposited over a ground surface may be oriented with an angle or a curve, or may be simply laid flat over the ground.
In the preferred embodiments of the invention, the C-shaped plastic sheet 12 is combined with an external removable cover 50 for creating a closed chamber 10.
A
removable cover 50 may readily be removed, making access, cleaning and maintenance of the bioreactor chamber 10 easy. As shown in FIG. 2, borders of cover 50 may be simply slided inside the upper portion of the repeating pattern of shape-sustaining supports 82. Cover 50 may also be made of a thin, rollable, transparent/translucent plastic sheet 12 such as a thinner or thicker fiberglass material that may incorporate its own portholes 52 (FIG.4) and devices that promote biomass growth. This arrangement provides a reliable sealing means of cover 50 over sheet 12 throughout the length of bioreactor chamber 10. Cover 50 may also be made of more common, low-cost, disposable, plastic films.
FIGS. 1, 2, 3 and further illustrate how a height-adjustable delta-shape angle-variable front panels 84 and back panel 86, or vertical boards 88 and 89 (FIG.
11) transfer weight of an elevated bioreactor 10 across the full width of the bioreactor 10 directly to the ground. This distribution of weight allows for panels 84, 86 and/or for boards 88, 89 to use low-cost construction materials such as wood, plastic-lumber, fiberglass, fiber-cement, clay, magnesium oxide, gypsum, or a combination thereof.
Boards and panels 82 may have a natural white color, or may be painted or covered with a white glossy coating or a reflective material.
Panels 84, 86 and boards 88, 89 perform multiple functions such as sustaining a desired configuration such as C-shape, L-shape, T-shape, U-shape, M-shape, or an oblique-shape configuration throughout the length of plastic sheet 12; they also act as light reflectors 120 and as height adjustors of shape-sustaining supports 80 to enable light exposure to underside of transparent/translucent plastic sheet 12.
To adjust the level of a bioreactor chamber 10 so as to maintain a substantially constant layer of water and biomass along the length of a bioreactor chamber 10, various height-adjustable means 80 are configured to cooperate with selected types of shape-sustaining supports. FIGS. 1, 2, 3, 5 and 11 illustrate a delta-shape support 80 wherein height adjustment is provided by varying the angle of a first panel 86 to change the angle of a second panel 84, which in turn results in height variation of chamber 10.
The fixation of panels 84 and 86 in a final position may be achieved via a system of tongues and grooves in panels 84 and 86, via screws or nylon ties or fastening means of the like.
FIG. 8 shows inflatable buoys 400 that may be pumped or deflated to adjust height of bioreactor chamber 10. FIGS. 9 and 10 illustrate a scaffold-type height-adjustable structure 80 that includes a horizontal bar 81 that may be affixed at a desirable height on two vertical pipes or poles 83 and 84. FIGS. 11 and 12 illustrate another type of height-adjustable structure 80 wherein by two vertical interlocking flat panels 88 and 89 cooperate together via multiple rails positioned at different heights. In another embodiment, panels 88 and 89 may slide into each other to vary height. In yet another embodiment, shape-sustaining supports may slide between two vertical rails (not shown) or are provided with cooperating movable wedges to vary height.
Traditionally, fiber reinforced plastic (FRP) sheets also referred to in this invention as "fiberglass" or plastic sheet 12, may be manufactured and supplied with different thicknesses. The semi-rigid transparent/translucent fibreglass (FRP) sheet 12 referred to in this invention relates to bendable rolls 26 of FRP sheets varying from 0.5mm to 1.2mm thick, 15 or 30 m long. Typically, thicker FRP sheets are too stiff to be reduced into rolls 26. Standard width of FRP sheets vary from 0.6m, lm to 1.2m and can also be custom-made to 1.6m wide. However, FRP sheets of various thicknesses can be readily adhered together establishing any desired width as necessary.
Plastic sheet 12 of bioreactor chamber 10 or of cover 50 (FIG. 4) may further include by attachment means or by embedding into the sheet 12 during the manufacturing process devices that promote, detect or monitor biomass growth such as, but not limited to, flexible wires, sensors (60), monitors, detectors, connectors, light emitting diode (LED) 40, computer chips, optical sensors, Bluetooth (RE) short-range connections (Bluetooth is a Trademark owned by Bluetooth(R) SIG), photovoltaic cells, batteries, microplate reader, and a combination thereof.
Also, various devices may be attached along borders of sheet 10. These may include hangers 30 (FIG. 4) for holding an air sparger system 28, LED tapes or ropes, instruments and other devices that promote, detect or monitor biomass growth as disclosed above. Said devices may also be attached or embedded into the elongate sealable extruded plastic profile 70 (FIG. 7) that joins opposing sheet edges 12 in closable bioreactor chambers 10.
FIG. 8 shows a bioreactor 10 positionable over a water surface. Bioreactor chamber 10 may float directly above a water surface, or may be supported by buoys 400 or by other floating systems 400. As an example, a closed bioreactor chamber 10 may be floated over a water channel, a dysfunctional raceway-type pond, a polluted water surface, a lake, a swampy land where isolating of a bioreactor content from an outside negative environment is required, and vice-versa.
Positioning a floating reflective film 120, such as foil bubble-back insulation-type reflective film on the underside of a floating bioreactor 10, provides additional sunlight to the bioreactor 10 in addition to the direct and sunlight sunlight that the system may receive. Buoyancy units 400 may also be inflatable; rising or lowering bioreactor 10 may help discharge some of the semi-liquid content 18 present in bioreactor chamber 10 or positioned in a plastic bag 20 or sleeve 20 inserted in bioreactor 10. Rising and lowering bioreactor 10 may also be used to generate waves or vibrations to create agitation in the liquid content 18 of bioreactor 10.
FIG. 6 also shows a plastic bag 20 being used as a liner inside bioreactor 10.
Plastic bag 20 may be sterilized by gamma ray or by other means to provide a sterile transparent/translucent environment for more sensitive strains of microalgae.
Water or other liquids may be also circulated around plastic bag 20 to control temperature of the bag content. Also, lining bioeractor 10 with a plastic bag 20 reduces cleaning and maintenance needs of bioreactor 10. Liner 20 may include an internal gas sparger 28 made of a thin plastic disposable material such as used for drip irrigation systems, while at the same time reducing cleaning and maintenance problems associated with bioreactors 10. Sparger tube 28 may also be made of a gas-permeable material such as, but not limited to, rubber particles for delivery of air and carbon dioxide inside plastic bag 20.
Bioreactor 10, may also be provided with a dewatering system. To dewater the biomass, plastic sleeve 20 is provided with an upper transparent/translucent film 310, and a bottom osmosis membrane 320. Plastic sleeve 20 is partially filled with water and a biomass suspension 18. Sleeve 20 is made to float in the bioreactor 10 over a fluid of higher solute concentration than it own fluid content such as, but not limited to, sea water. It is known that any liquid of lower solute concentration flows through an osmosis membrane to a liquid of higher solute concentration to seek equilibrium. This flow effect causes dehydration of biomass 18.
In another embodiment of the invention (FIG. 8), dewatering of the biomass may be achieved by providing a sleeve 20 made entirely of an osmosis membrane and partially filled with salt water inside said sleeve 20. Water content in diluted biomass 16 present in bioreactor 10 permeates through the osmosis membrane 320 of sleeve 20 and flows towards the higher solute concentration present inside sleeve 20 causing dehydration of biomass in bioreactor 10.
As an example of how multiple rows of bioreactor chambers 10 may cooperate together, FIG. 5 shows an integrated raceway-type pond-photobioreactor 10 wherein ends of two rows of bioreactor chambers 10 are connected via a U-shaped water tank 500. Other open or closed forms of layouts of bioreactor chambers 10 in fluid communication with each other are provided, in the same manner, using water tanks 500.
Extension of length of a bioreactor chamber 10 is simply achieved by adhering overlappingly ends of two adjacent sheets 12. Preferably, a shape-sustaining support 80 may be located at a position where the two chambers 10 are joined together.
FIG. 9 and 10 show a bioreactor 10 incorporating a first embodiment of a temperature control system through a water jacket created created by a hollow spacer 24 placed between two layers of thin plastic sheets 12 and 22. Both plastic sheet layers 12 and 22 are inserted in a repeating pattern of shape-sustaining support 80 or in a repeating pattern of C-shaped bracket 110.
FIGS. 9 and 10 also show an elevated scaffold-type U-shaped metal structure 80 that supports bioreactor 10; these elevated U-shaped structures 80 may comprise a horizontal bar 81 which ends are supported by two vertical poles or pipes 83 and 85.
The height and angle of horizontal bar 81 are adjustable for rapid adjustment of the bioreactor chamber 10 to keep a substantially constant water depth along the length of the extra long chamber 10. In this type of modular structure 80, multiple scaffolds 80 may also be stacked above each other or sideways to reduce land usage while still allowing sunlight to penetrate from underside of bioreactor 10.
FIG. 10 shows another embodiment of bioreactor 10 having an L-shape configuration. This L-shaped bioreactor 10 may also include an integral water jacket located around the water pocket 13; as disclosed earlier, the water jacket of the invention is made of a second layer of plastic sheet 22 laid over an original layer of plastic sheet 12 with a hollow spacer 24 placed in-between them.
In the preferred embodiments of the invention, the two ends of an elongate bioreactor 10 are in fluid communication with a water tank 500. The elongate chamber may also be closed by two bulkheads (not shown). A bulkhead is best made of a flat plate-shaped body configured with substantially a similar cross-sectional dimension than a chamber 10 surrounded by soft seal affixed to the bulkhead contour.
Bulkheads may be also placed anywhere and at any time inside a bioreactor chamber 10 to close or isolate a section of a chamber 10.
In an embodiment of the invention as shown in FIG. 13, the U-shaped water tank 500 may also include a mixing system 520 comprising a spiral-shaped tube 522, submerged in water tank 500 with a substantially smaller diameter gas-permeable tube 28 partially inserted in said spiral-shaped tube 522 to supply air and carbon dioxide;
mixing of gases in water tank 500 or via an attachment underneath bioreactor chamber 10 may also be achieved by a pump or injector means that circulates culture;
the pump may also include a thermocontrol system. Bubbles generated by gas-permeable tube 28, after mixing with water in the long spiral-shaped pipe 522 exit parallel to the water and biomass present in chamber 10, causing both agitation and a forward motion in chamber 10.
FIG. 14 shows a linear gas mixing device 520 comprising of two long straight pipes 532 and 534; at least one pipe 532 has a larger diameter. Pipes 532 and 534 are connected together outside water tank 500; optionally, a small portion (530) of larger pipe 532 may be placed inside tank 500 with its exit 530 positioned at a more elevated location than entry of pipe 530. However, this is not required when other methods of water and biomass circulation is provided to create agitation in bioreactor chamber 10.
In this linear mixing device 520 (wihout exit pipe 530 in tank 500), the two pipes 532 and 534 are both connected to the bottom of tank 500 and are always filled with water and biomass suspension. A smaller gas-permeable tube 28 partially inserted inside the bigger pipe 532, supplies air and carbon dioxide; gas bubbles generated by tube 28 inside pipe 532 create a natural forward flow in pipe 532 and consequently causes a suction effect in pipe 534, both actions causing water circulation at the bottom of tank 500 which further enhances mixing of gases with water and biomass.
FIGS. 14 and 15 also illustrate how an evaporative water cooling system 600 of the invention may cool a U-shaped water tank 500 attached to bioreactor 10 or may cool directly a bioreactor chamber 10 via a connection attached anywhere underneath a bioreactor chamber 10. The water cooling system 600 may be in fluid communication directly with or through a heat exchanger (not shown) with a U-shaped tank 500.
As illustrated in FIG. 15, the evaporative cooling system 600 comprises an elongate heat pipe 534 such as a metal pipe, containing a circulating water in fluid communication with the bottom of bioreactor chamber 10; heat pipe 534 is surrounded by a layer of a porous material 620 such as, but not limited to, charcoal, expanded clay pebbles, evaporative wick, and porous materials of the like; the porous material 620 is contained inside a wire meshing; a drip watering system 622 is positioned above the porous material 622 and is continuously or automatically wetting the porous material 620; an elongate larger enclosure 720 surrounds the wire meshing; an air duct 710 one end is partially inserted inside larger enclosure 720 and other end is attached to an elevated wind turbine ventilator 700; the ventilator 700 creates an air draft in the larger enclosure 720 sucking air through the enclosure 720 and causing evaporation of moisture present in the porous material 620 which in turn creates a cooling effect of heat pipe 534. When the cooling system 600 operates in tandem with the gas mixing system 520 as shown in FIGS. 14 and 15, a natural water circulation is created in heat pipe 534, increasing the efficiency of both the low-cost mixing system and the low-cost cooling system of the invention.
In FIGS. 14 and 15, arrows represent fluid flows. WD represents the flow direction of drip water in pipe 622, A+C represents Air and Carbon dioxide flow in tube 28, W+B
represents flow of Water and Biomass. Similarly, W+B+A+C represents the flow of Water, Biomass mixed with Air and Carbon dioxide.
Agitation of biomass such as microalgae in bioreactor 10 may be achieved by a pump (not shown), a water wheel (not shown) or a wave generator (not shown).
In embodiments of the invention that require a sterile cultivation, when using an agitation equipment such as a water wheel or a wave generator, the agitation equipment is configured to maintain a degree of air-tightness that prevents any form of air contamination from outside.
Certain features of this invention may sometimes be used to advantage without a corresponding use of the other features. While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
Claims (20)
1. A low-cost integrated pond-photobioreactor for biomass production comprising:
- an elongate thin, flat, bendable, rollable, transparent/translucent semi-rigid plastic sheet;
- a repeating pattern of shape-sustaining supports elevated above ground; each of said shape-sustaining supports including a cavity with at least two sidewalls; and - two water tanks;
an integrated pond-photobioreactor created by enclosing fittingly said plastic sheet in said cavity and by connecting sealingly ends of said enclosed plastic sheet to said water tanks.
- an elongate thin, flat, bendable, rollable, transparent/translucent semi-rigid plastic sheet;
- a repeating pattern of shape-sustaining supports elevated above ground; each of said shape-sustaining supports including a cavity with at least two sidewalls; and - two water tanks;
an integrated pond-photobioreactor created by enclosing fittingly said plastic sheet in said cavity and by connecting sealingly ends of said enclosed plastic sheet to said water tanks.
2. The integrated bioreactor of claim 1, wherein said enclosed plastic sheet substantial width corresponding to said cavity substantial perimeter defines an integrated bioreactor incorporating own integral cover; or said plastic sheet shorter width defines an open-top bioreactor that cooperates sealingly with an external removable cover.
3. The integrated bioreactor of claim 1, wherein the configuration of said cavity determines the shape of a bioreactor; said configuration selected from the group consisting of a pond-shape comprising a flat base portion flanked between two curved sidewalls; an L-shape or a T-shape comprising a flat base portion with a U-shaped recess located respectively in one side or in the middle portion of said flat base; an oblique-shape; a variable-shaped bioreactor wherein shape, depth and width vary along the length of said bioreactor; and a combination thereof.
4.
The integrated bioreactor of claim 1, wherein said shape-sustaining supports comprising, but not limited to, panels, boards, planks, bars, plates, poles, sticks, inflatable-deflatable devices, and a combination thereof.
The integrated bioreactor of claim 1, wherein said shape-sustaining supports comprising, but not limited to, panels, boards, planks, bars, plates, poles, sticks, inflatable-deflatable devices, and a combination thereof.
5. The integrated bioreactor as in claims 1 and 4, wherein said shape-sustaining supports are made of materials selected from the group consisting of, but not limited to, plastic composite, plastic-lumber, magnesium oxide, gypsum, metal, fiberglass, wood, laminated wood, cementitious material, ceramic material, clay, ceramic, glass, bamboo, fiber cement, fiber composites, and a combination thereof.
6. The integrated bioreactor of claim 1, wherein said shape-sustaining supports further cooperating with height-adjustable means, said height-adjustable means selected from the group consisting of angle-variable panels, vertical interlocking panels, vertical panels sliding between two vertical rails, cooperating wedges, and a combination thereof.
7. The integrated bioreactor of claim 1, wherein ends of two parallely-positioned of said plastic sheets enclosed in two of said repeating pattern of shape-sustaining supports communicate fluidingly with each other via said water tanks, defining a raceway-type integrated pond-photobioreactor.
8. The integrated bioreactor as in claims 1 and 2, wherein said plastic sheet and/or said cover further comprising devices embedded and/or attached to said plastic sheet and/or cover to promote, detect or monitor biomass growth, said devices selected from the group consisting of, but not limited to, portholes, flexible connectors, sensors, monitors, detectors, light emitting diode tapes (LED), computer chips, optical sensors, Bluetooth (RF) short-range connectors, photovoltaic cells, batteries, microplate readers, and a combination thereof.
9. The integrated bioreactor as in claims 1 or 2, wherein said transparent/translucent plastic sheet is selected from the group of materials consisting of, but not limited to, fiber reinforced plastic (FRP), low density polyethylene (LDPE), high-density polyethylene (HDPE), hard acrylic (PMMA), polyvinyl chloride (PVC), polycarbonate (PC), composite plastics, and a combination thereof.
10. The integrated bioreactor of claim 1, further including a temperature control system provided by circulating a heating or cooling fluid inside a water jacket; said water jacket comprising a hollow elongate transparent/translucent spacer enclosed between two layers of said thin plastic sheets inserted in said cavity; said hollow spacer walls including, but not limited to, wavy walls, double-walls, multi-wall PC sheet, bubble-shape blister sheet, air-bubble sheet and transparent distance providers of the like.
11. The integrated bioreactor of claim 1, wherein said chamber further including a solar reflective means to reflect sunlight underside said elevated transparent/translucent bioreactor chamber in addition to natural sunlight; said solar reflective means comprising, but not limited to, orientable solar reflective film, reflective paint, reflective minerals or a reflective film positioned on the ground.
12. The integrated bioreactor of claim 1, wherein said bioreactor chamber further including a water-gas mixing device; said mixing device comprising two long and substantially large diameter pipes; said first and second large pipes laid parallel to each other and in fluid communication with each other on one end, and in communication with bottom of said elongate bioreactor chamber or with bottom of a water tank attached to said chamber on the other end; a smaller gas-permeable tube inserted into said first pipe at a location where said two pipes are connected; said tube supplied with gases; gas bubbles generated from said gas-permeable tube travel and mix with water and create a positive forward flow in this first pipe and a negative flow in the second pipe; said gas flow creating a water circulation that further assists said water-gas mixing.
13. The integrated bioreactor of claim 1, wherein said bioreactor chamber further including an evaporative cooling system; said cooling system comprising:
- an elongate heat pipe, such as a metal pipe, in fluid communication with the bottom of said bioreactor chamber or of said water tanks, said heat pipe surrounded by - an outer layer of a porous material such as, but not limited to, charcoal, expanded clay pebbles or evaporative wick; said porous material contained inside and surrounded by - a larger wire meshing surrounding the heat pipe;
- a drip watering system positioned above the porous material;
- an elongate larger enclosure surrounding said wire meshing; and - an air duct, one end partially located inside said larger enclosure and other end attached to an elevated wind turbine ventilator;
said ventilator creating an air suction in said larger enclosure causing evaporation of water present in porous material which in turn creates a cooling effect around the heat pipe.
- an elongate heat pipe, such as a metal pipe, in fluid communication with the bottom of said bioreactor chamber or of said water tanks, said heat pipe surrounded by - an outer layer of a porous material such as, but not limited to, charcoal, expanded clay pebbles or evaporative wick; said porous material contained inside and surrounded by - a larger wire meshing surrounding the heat pipe;
- a drip watering system positioned above the porous material;
- an elongate larger enclosure surrounding said wire meshing; and - an air duct, one end partially located inside said larger enclosure and other end attached to an elevated wind turbine ventilator;
said ventilator creating an air suction in said larger enclosure causing evaporation of water present in porous material which in turn creates a cooling effect around the heat pipe.
14. The integrated bioreactor of claim 1, wherein said elongate bioreactor further including a transparent/translucent liner means, said liner means selected from the group consisting of a single layer of transparent/translucent plastic film, a disposable transparent/translucent plastic sleeve, a sterile disposable transparent/translucent plastic sleeve incorporating a disposable sparger tube, a sleeve having an upper layer comprising a transparent/translucent film and a lower layer comprising an osmosis membrane, a sleeve entirely made of an osmosis membrane, and a combination thereof.
15. The integrated bioreactor of claim 14, wherein said sleeve with an upper transparent/translucent film and a lower osmosis membrane dewaters a semi-liquid content contained in said same sleeve; said dewatering achieved when the water content of lower solute concentration in said sleeve floating over a surface of water of higher solute concentration, such as sea or salt water provided in said bioreactor chamber or outside of said bioreactor permeates through said osmosis membrane and dewaters the water content of biomass in the sleeve.
16. The integrated bioreactor of claim 14, wherein said sleeve made entirely of an osmosis membrane and partially filled with a liquid of higher solute concentration, such as sea water, dewaters a semi-liquid biomass content present in said bioreactor chamber.
17. The integrated bioreactor of claim 1, wherein said elongate chamber floats directly over a surface of water, or floats indirectly over a surface of water when said chamber is supported by buoys; said buoys may be inflatable enabling lifting of a portion of said elongate chamber so as to discharge a semi-liquid content contained in said bioreactor chamber.
18. A low-cost integrated pond-photobioreactor for biomass production comprising:
- an elongate thin, flat, bendable, rollable, transparent/translucent semi-rigid plastic sheet;
- a repeating pattern of shape-sustaining supports such as C-shaped brackets;
said brackets configured with a generally flat base portion flanked between two curved sidewalls; said brackets sidewalls front edges including an inwardly-oriented reverse bend on each side; said brackets enclosing said plastic sheet and sustaining a C-shape configuration along said plastic sheet length; the plastic sheet C-shape configuration defining a bioreactor chamber;
two water tanks;
- a repeating pattern of load-bearing structures for supporting in an elevated position said chamber and exposing said chamber to sunlight from all directions including from underside, said structures including, but not limited to, reverse U-shaped structures, arcuate structures, greenhouse structures, warehouse structures, and a combination thereof;
the combination enclosed plastic sheet, brackets, water tanks and support structures defining an integrated pond-photobioreactor.
- an elongate thin, flat, bendable, rollable, transparent/translucent semi-rigid plastic sheet;
- a repeating pattern of shape-sustaining supports such as C-shaped brackets;
said brackets configured with a generally flat base portion flanked between two curved sidewalls; said brackets sidewalls front edges including an inwardly-oriented reverse bend on each side; said brackets enclosing said plastic sheet and sustaining a C-shape configuration along said plastic sheet length; the plastic sheet C-shape configuration defining a bioreactor chamber;
two water tanks;
- a repeating pattern of load-bearing structures for supporting in an elevated position said chamber and exposing said chamber to sunlight from all directions including from underside, said structures including, but not limited to, reverse U-shaped structures, arcuate structures, greenhouse structures, warehouse structures, and a combination thereof;
the combination enclosed plastic sheet, brackets, water tanks and support structures defining an integrated pond-photobioreactor.
19. The integrated bioreactor of claim 18, wherein a closable-type bioreactor chamber further including an elongate sealable plastic extruded profile for sealing two opposing longitudinal edges of said plastic sheet ; said opposing edges meeting optionally at a middle portion or at a close proximity to a sidewall of said elongate chamber.
20. The integrated bioreactor as in claims 1 and 18, wherein said rollable bioreactor is collapsible into a roll and said supports are collapsible by disassembling or by folding.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2764291 CA2764291A1 (en) | 2012-01-16 | 2012-01-16 | Low-cost integrated pond-photobioreactor |
| US14/362,904 US20140315290A1 (en) | 2011-12-07 | 2012-10-22 | Low-cost photobioreactor |
| AU2012350117A AU2012350117A1 (en) | 2011-12-07 | 2012-10-22 | Low-cost photobioreactor |
| PCT/CA2012/050750 WO2013082713A1 (en) | 2011-12-07 | 2012-10-22 | Low-cost photobioreactor |
| CA2858204A CA2858204A1 (en) | 2011-12-07 | 2012-10-22 | Low-cost photobioreactor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2764291 CA2764291A1 (en) | 2012-01-16 | 2012-01-16 | Low-cost integrated pond-photobioreactor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2764291A1 true CA2764291A1 (en) | 2013-07-16 |
Family
ID=48794286
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2764291 Abandoned CA2764291A1 (en) | 2011-12-07 | 2012-01-16 | Low-cost integrated pond-photobioreactor |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2764291A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2942383A1 (en) * | 2014-03-18 | 2015-11-11 | AVA-Co2 Schweiz AG | Device for location-independent treatment of biomass |
| GB2539936A (en) * | 2015-07-01 | 2017-01-04 | Univ Nelson Mandela Metropolitan | Microalgae cultivation process and equipment |
| CN115024272A (en) * | 2022-07-15 | 2022-09-09 | 苑春亭 | Water floating air shed capable of increasing water temperature of pond |
-
2012
- 2012-01-16 CA CA 2764291 patent/CA2764291A1/en not_active Abandoned
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2942383A1 (en) * | 2014-03-18 | 2015-11-11 | AVA-Co2 Schweiz AG | Device for location-independent treatment of biomass |
| GB2539936A (en) * | 2015-07-01 | 2017-01-04 | Univ Nelson Mandela Metropolitan | Microalgae cultivation process and equipment |
| US11795421B2 (en) | 2015-07-01 | 2023-10-24 | Nelson Mandela University | Microalgae production process and equipment |
| CN115024272A (en) * | 2022-07-15 | 2022-09-09 | 苑春亭 | Water floating air shed capable of increasing water temperature of pond |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20140315290A1 (en) | Low-cost photobioreactor | |
| US9102923B2 (en) | Photobioreactor | |
| CN101870953B (en) | Method for culturing microalgae | |
| US8479441B2 (en) | Light distribution apparatus for cultivation of phytoplankton and other autotrophic aquatic species in an aquatic medium | |
| US9260685B2 (en) | System and plant for cultivation of aquatic organisms | |
| US20130109008A1 (en) | Method and apparatus for growing photosynthetic organisms | |
| US8658420B2 (en) | Photobioreactor for algae growth | |
| MX2008010770A (en) | Photobioreactor and uses therefor. | |
| US10287538B2 (en) | Device for producing a photosynthetic culture by means of a photo-bioreactor and at least one light distributor | |
| BR112015008979B1 (en) | PHOTOBIORREACTOR AND PROCESS FOR CROP AND MICRO ALGAE GROWTH | |
| ES2370546A1 (en) | Apparatus and method for growing biological organisms for fuel and other purposes | |
| CN102939370A (en) | Device and method for photosynthetic culture | |
| CA2836218A1 (en) | Multilevel photobioreactor | |
| CN105039138A (en) | Microalgae culture system with solar cell panels and culture method thereof | |
| MX2008010831A (en) | Cooling device for use in an electric arc furnace. | |
| CA2764291A1 (en) | Low-cost integrated pond-photobioreactor | |
| CN204918572U (en) | U type runway pond photobioreactor | |
| CA2761251A1 (en) | Fast erectable bioreactor | |
| US20210002595A1 (en) | Culture tank | |
| CN203462055U (en) | Photobioreactor for preventing microalgae attachment to wall in airlift mixing way | |
| US20160145552A1 (en) | Floating photobioreactor system comprising a floating photobioreactor and an integrated paddle wheel and an airlift and methods of use | |
| WO2010103154A2 (en) | Method for the culture of microorganisms and photobioreactor used in same | |
| WO2013017723A1 (en) | Photobioreactor for culturing photoautotrophic microorganisms | |
| Griffiths | 5 Microalgal Cultivation | |
| US20230030365A1 (en) | Buoyant photobioreactor arrangement |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |
Effective date: 20170118 |