WO2010011320A1

WO2010011320A1 - Bioreactor system for mass production of biomass

Info

Publication number: WO2010011320A1
Application number: PCT/US2009/004269
Authority: WO
Inventors: James Charles Juranitch
Original assignee: GLOBAL ENERGIES LLC
Current assignee: GLOBAL ENERGIES LLC
Priority date: 2008-07-23
Filing date: 2009-07-23
Publication date: 2010-01-28
Anticipated expiration: 2011-01-23

Abstract

A bioreactor arrangement for growing a biomass has a source of feedstock, a biomass growth surface, and a feedstock transfer arrangement that delivers the feedstock to the biomass growth surface. A biomass harvester removes the biomass from the biomass growth surface. The source of feedstock is in the form of a pool, and includes a pan for the feedstock. The biomass growth surface is configured as an absorbent belt or as a ribbed belt. A semi-permeable membrane has a porosity of approximately 30 microns, and prevents viral and sewage contamination of the biomass. The biomass growth surface is either open or closed to the atmosphere. When closed, a CO2 enhanced and temperature controlled environment is provided. Growth illumination is enhanced by a light enhancing lens or a mirror. A tracking arrangement reorients the mirror to maintain enhanced illumination on the biomass growth surface.

Description

Bioreactor System for Mass Production of Biomass Relationship to Other Application

This application claims the benefit of the filing date of United States Provisional Patent Application Serial Number Serial No. 61/135,848 filed July 23, 2008, Conf. No. 7173 (Foreign Filing License Granted) in the name of the same inventor as herein. The disclosure in the identified United States Provisional Patent Application is incorporated herein by reference. Background of the Invention

FIELD OF THE INVENTION This invention relates generally to energy production systems, and more particularly, to a biomass production system (i.e., a bioreactor).

DESCRIPTION OF THE RELATED ART

In the current energy environment there is continuing pressure to produce more products and energy in a cost effective and clean way. Fuel prices continue to climb, and emission standards continue to tighten. Most of the modern world has attempted to limit the amount of carbon dioxide that is emitted into the atmosphere. It is considered by some persons of skill in the art that carbon dioxide has some responsibility in the climatic changes commonly referred to as "global warming."

There is a need, therefore, for a biomass production system that sequesters carbon dioxide in large quantities from the environment before conversion of its components into a feedstock for fuel that ultimately can be burned.

There is additionally a need for a biomass production system that minimizes the amount of carbon dioxide that is allowed to re-enter the atmosphere from the fuel that is produced. All combustion processes emit carbon dioxide, including modern cars, boats, planes, and other means of transportation. The world requires continually more high density transportable energy, while at the same time conventional oil reserves are dwindling. Until the present invention, no carbon efficient (neutral, or minimally positive carbon foot print) biomass high production system has been devised. The work of many people is focused on the production of biomass. Existing prior art such as the work of Malcolm Kertz (Pub number US 2007/0289206 Al) have significant limitations and compromises that may have been designed-in to facilitate convenient collection or harvesting of the produced biomass. Additional significant compromises exist in the prior art in the areas of available photosynthesis energy (light exposure) and in the type and families of biomass that can effectively be produced. Many strains of biomass require a still environment for maximum production, and are not amenable to being pumped. This is evident in nature when one considers that only a small amount of biomass will grow in a running river, as opposed to the greater growth rate in a stagnant pond. Stringy or common salt water style biomass are also not conducive to being pumped. Many other prior art arrangements do not permit intensified photosynthesis or optimized use of bioreactor growth per unit area of footprint used (i.e. , density). Summary of the Invention The foregoing and other deficiencies and problems in the prior art are addressed and corrected by this invention which provides a bioreactor arrangement for growing a biomass. In accordance with the invention, the bioreactor arrangement is provided with a source of feedstock. A biomass growth surface supports the biomass as it is grown, and a feedstock transfer arrangement delivers the feedstock to the biomass growth surface. Additionally, a biomass harvesting arrangement for removing the biomass from the biomass growth surface.

In one embodiment of the invention, the source of feedstock is in the form of a pool of feedstock. The source of feedstock includes, in some embodiments, a pan of feedstock. In an advantageous embodiment of the invention, the biomass growth surface is configured as an absorbent belt. In other embodiments, the biomass growth surface is a ribbed belt.

In embodiments of the invention where the feedstock contains viral material, bacteria, or sewage, there is provided a filter having the characteristic of a semi-permeable membrane. In a practicable embodiment of the invention, the filter has a porosity of less than approximately 30 microns. In such an embodiment, the feedstock transfer arrangement can be in the form of a pool of feedstock disposed on one side of the filter.

In some embodiments of the invention, the biomass growth surface is open to the atmosphere. However, in embodiments where the biomass growth surface is closed to the atmosphere, the biomass growth surface is advantageously subjected to a CO₂ enhanced environment. Additionally, the biomass growth surface is, in some embodiments, subjected to a temperature controlled environment, and enhanced illumination by operation of a light enhancing arrangement. The light enhancing arrangement will, in respective embodiments, include any of a light-focusing lens, a lenticular lens, or a reflective surface. The reflective surface can be simply a light- colored surface, or a mirror. In a further advantageous embodiment, there is provided a tracking arrangement that reorients the reflective surface so as to maintain a predetermined relation to a moving source of growth light. Thus, in embodiments where the sun is the source of growth light, the tracking arrangement will continuously adjust the orientation of the reflective surface to maintain enhanced illumination on the biomass growth surface.

In some embodiments of the invention, the biomass growth surface is tilted at an angle responsive to the location of the sun relative thereto. Li other embodiments, however, the biomass growth surface is oriented substantially vertically.

Harvesting of the biomass is, in some embodiments of the invention, performed by a wiper system that automatically harvests the biomass. Harvesting is performed, in accordance with respective embodiments of the invention, in continuous or batch modes. An escapement arrangement facilitates removal of the harvested biomass. In embodiments of the invention where the biomass is intended as food for animals or humans, the structure associated with the bioreactor for supporting same is formed of a material that can be sterilized. In some embodiments, the material is stainless steel. The feedstock transfer arrangement delivers the feedstock to the biomass. In one embodiment of the invention, the feedstock transfer arrangement is a drip system. In other embodiments, the feedstock transfer arrangement is a spray system.

This system of the present invention overcomes the deficiencies of the prior art, and achieves higher biomass production and greater harvested mass, in a cost effective, and energy efficient system. Some illustrative advantages of the present invention include:

• successful growth of any family of biomass in the inventive system, including the stringy salt water types of biomass, by direct exposure to sunlight, intensification of the available natural light, concentration of sunlight through the use of lenticular surfaces, and concentration and focusing of the sun by using continuously sun-tracking mirrors;

• optimization of photosynthesis by extending the duration of the period of sunlight per day by the automatic repositioning of the bioreactor relative to the position of the sun with the use of a turntable system.

• minimization of water use by virtue of the closed, or sealed, reactor of some embodiments of the present invention, enabling a sterile production environment in some embodiments;

• controlling the temperature and chemical composition of the growth atmosphere, which can, in respective embodiments of the invention, be carbon dioxide enriched or modified with other gaseous growth enhancing additives;

• monitoring and modifying continuously the nutrient content of the feedstock; • automating production and harvesting in continuous or batch modes of harvesting;

• greatly increasing bioreactor density.

In the present invention, bioreactor density is very high. In one embodiment, the effective growth area over conventional pond style environments or footprints is increased by over 700% depending on the style of bioreactor chosen, and its location or orientation on the earth, versus the light requirements of the strain of biomass being produced.

Many strains of biomass respond with dramatic increases in production when the exposure to sunlight is enhanced or extended. Availability of sunlight has heretofore been a limiting factor in the maximization of biomass production. The combination of the control over temperature and composition of the growth atmosphere, when used in combination with intensified sun light, and high levels of nutrient feeding systems as described herein, further increases biomass production.

Although much of the development herein described has been directed toward transportable bio-fuel mass production, the present system is also useful for human food production, as well as pharmaceutical production, when configured in stainless steel or other materials capable of being adequately sterilized. Brief Description of the Drawing

Comprehension of the invention is facilitated by reading the following detailed description, in conjunction with the annexed drawing, in which:

Fig. 1 is a simplified schematic front view representation of a pan style bioreactor with mirrored light collector system (Style "A");

Fig. 2 is simplified schematic top view representation of a pan style bioreactor with mirrored light collector system (Style "A"); Fig. 3 is a simplified schematic representation of a ribbed belt, and large scale permeable media belt, bioreactor side view showing an inclined angle of incidence to the light source (Style "B");

Fig.4 is a simplified schematic side view representation of a ribbed belt, and large scale permeable media belt, bioreactor in a vertical design (Style "B"); Fig. 5 is a simplified schematic front view representation of a ribbed belt, or large scale permeable media belt, bioreactor spray or drip bar system (Style "B");

Fig. 6 is a simplified schematic representation of a small scale (Micron level) semi-permeable membrane bioreactor with a conveyor belt (Style "C");

Fig. 7 is a simplified schematic representation of a small scale (Micron level) semi-permeable bioreactor without a conveyor belt (Style "C"); Fig. 8 is a simplified schematic representation of a turntable system that is useful for all bioreactors herein described; and

Fig. 9 is a simplified schematic representation of a collection system for all biomass product. Detailed Description

Three families, or styles, of biomass production systems are described herein. Each such system or style has respective features that render it desirable for different families of biomass production, and for the nutrient feedstock being used. The light concentration and/or turntable system, and the harvest or collection systems for the end product is the same for each of the biomass reactors styles. The most typical light source is the sun, but artificial light can be used to supplement biomass production.

Fig. 1 is a simplified schematic front view representation of a pan style bioreactor 9. In this specific illustrative embodiment of the invention, pan style bioreactor 9 is approximately 14 feet tall and 5.5 feet wide, exclusive of curved mirrors 1 and 2. The production biomass pans are designated as biomass pans 3 in the figure.

Biomass strain and feed stock are introduced into biomass pans 3 through pipe system 25 which is controlled by valve 26. The system can, in certain embodiments of the invention, be configured as a constant pressure metered orifice central system. Alternatively, the system can, in other embodiments, be formed using individual control valves, as persons skilled in the art will recognize.

A simple cylinder and seal system 5 seals the end of biomass pans 3, the production pan. The figure illustrates an air, or electric, cylinder (not specifically designated) actuating the seal (not specifically designated). However, any actuation system can be used in the practice of the invention. Individual actuators are used, as shown in the drawing. Alternatively, a central actuator (not shown) can be used.

An actuator 4 powers a wiper that facilitates the harvesting of the biomass (not shown). The actuator can be a rodless cylinder, electric ball screw, or any other type of actuator known to persons skilled in the art. In this specific illustrative embodiment of the invention, the pans have individually associated actuators. In other embodiments, however, a central actuator (not shown) powers all wipers synchronously. When in a harvest operation, actuator 5 will open seal 27 at the end of production biomass pan 3. A wiper 26 is drawn across the production pan to allow the biomass and its feed stock to drop into a chute and an escapement 19. The escapement is powered by an actuator 20. The biomass is harvested and collected between a transfer line 24 and a liquid outlet port 23. Outlet port 23 will deliver the harvested material (not shown) through a typical filtration/harvesting system (not shown).

A pair of curved mirrors 1 and 2 are actuated by an actuator 22 (not shown in this figure, see, Fig. 3) on at least one axis, and preferably on two axes. The mirrors are mounted so as to direct the sunlight (not specifically designated) onto the growth surface. In this specific illustrative embodiment of the invention, the angle of incidence will typically be 45 degrees. However, any other appropriate angle can be used in the practice of the invention. In this embodiment, mirror 1 operates in synchrony with mirror 2. The bioreactor of the present invention typically will be oriented to face a generally southern direction, as can be seen in Fig. 9. Mirror 1 is programmed to focus the sun on the growth surface before noon. Mirror 2 is programmed to focus the mirror on the growth surface in the afternoon. In the practice of certain embodiments of the invention, sun tracking mirrors (not shown) can be employed.

In embodiments where the reactor is configured without mirrors it would typically be mounted on a turntable 33, as seen in Fig. 8. The turntable can be driven by gear motor 34 or any rotational drive familiar to persons skilled in the art. In this embodiment, the drive is programmed to follow the path of the sun and thereby maximize the exposure of the biomass so as to maximize photosynthesis. In a preferred embodiment, the turntable will have the harvesting escapement chute 19 installed coaxially with the rotational axis of the turntable. This present design facilitates continuous harvesting operations. In other embodiments, however, the escapement chute is placed off of the rotational axis to minimize the rotational footprint. In such a configuration, rotational drive 34 is programmed to a "home" position where chute 19 is oriented to effect a batch harvesting mode.

Figs. 1 and 3 show an atmospheric inlet 16. As seen in these figures, there is additionally provided in this specific illustrative embodiment of the invention a forced or natural convection outlet 17. Atmospheric inlet 16 and convection outlet 17 serve at least two purposes. First, they facilitate temperature control in response to a temperature sensor 10 and a controller 11, and they also accelerate the natural flow of carbon dioxide over the growth surface. In growth modes of artificially high carbon dioxide environments, or other growth enhancing atmospheres, atmospheric inlet 16 and convection outlet 17 are, in some embodiments, removed and a heat exchanger 6 is then controlled by temperature sensor 10 and controller 11. This configuration also allows for a sealed or sterile environment, hi artificially enhanced growth environments the carbon dioxide volume is injected into the gaseous environment through a jet 8 (see, Fig. 3), or directly into the biomass growth formula through an orifice 7, as seen in Figs. 1, 6 and 7. Excessive pressure is ejected through a port 18. Closed loop control of the carbon dioxide or other growth enhancing gasses is, in some embodiments, scheduled through a sensor 12, a controller 13, and a control valve 14. For some embodiments of bioreactor 9 described herein, a sealing translucent front panel 21 is used to protect the growth surface from contamination, minimize evaporation, and enable control the environment. Front panel 21 maybe a glass panel, or the design can be enhanced for augmented light collection by lenticular panels 35 (see, for example, Fig. 6). In the embodiments of Figs. 3, 4, and 5, bioreactor 9 is a ribbed belt, or large scale permeable media belt, bioreactor. In this embodiment, belt 36 is a "wicking" style of media such as cloth that allows nondiscriminatory growth of biomass as enhanced by the nutrients continuously pumped through inlet control valve 31 and control valve 32, or a semi-nonporous ribbed belt formed of nylon, rubber, or another flexible media. Depending upon the type of nutrients used, sump 53 or 40 can be batch processed. The nutrients or feed stock are pumped by a pump 28 and distributed through a manifold 29 to a spray bar, or drip bars 30 (see, Fig. 5). The ribbed belt, and large scale permeable media 36 is, in this embodiment, oriented at an advantageous angle as seen in Fig. 3, or it maybe vertical as seen in Fig. 4. The feedstock sump is, in this embodiment of the invention, constructed illustratively as sump arrangement 40 (Fig. 4) to allow the belt to be submerged in the nutrients. A scraper 37 removes, or harvests, the biomass and deposits it by gravity into chute 19. Figs. 6 and 7 show small scale (Micron level) semi-permeable membrane bioreactors. In this embodiment of the invention the semi-permeable membrane discriminates between nutrients and bacteria. In this specific illustrative embodiment of the invention, the membrane filters out all particles larger than 250 angstroms. This sequesters the bacteria and the viruses from being passed to the biomass growth area 51 versus the nutrient rich feedstock area 52. In this specific illustrative embodiment of the invention, a belted arrangement 48 is used to promote growth and harvest of biomass, or area 51 can be left open for biomass growth and agitated by an agitator 47.

In enhanced carbon dioxide or other growth educing atmospheres the gas is introduced through inlet 7 (not shown in this figure, see Fig. 1) and expelled through check or port 18 (not shown in this figure, see Fig. 3) similar to all other embodiments of bioreactor 9 described herein. Nutrient feeding is accomplished through a port 42 and returned through a port 43. It can be continuously fed or batch processed. Clean biomass production fluid is brought into area 51 by inlet 45 and the biomass is harvested through outlet 43. In the embodiment of Fig. 7, clean H₂O enters area 51 at inlet 45, and H₂O is harvested, or drained, at outlet 44. CO₂ enters area 51 at inlet 7. All other features previously described such as temperature control, and light augmentation also apply to this family of bioreactors that have herein been described are not shown in some of the figures, such as Fig. 7, for sake of improved legibility. Growth collector 41 is similar to scraper 37, described above, but is shown schematically in this figure with an external transfer line (not specifically designated) integrated into its design.

A bioreactor style "C" with a small scale (Micron level) semi-permeable membrane constitutes an embodiment of the invention that also is temperature controlled by a large scale sump system (not shown) and introduced through the nutrient flow of ports 42 and 43 in the continuous flow implementation. Area 51 is, in this specific illustrative embodiment of the invention, temperature controlled through conduction of the fluid in area 52 through a membrane 46.

Fig. 9 shows a transfer line collection system that can be used with any of the embodiments of bioreactor 9. In this specific illustrative embodiment of the invention, smaller transfer lines 49 feed into a collection transfer line 50 to collect automatically all produced biomass. Fig. 9 further shows a quantity of 20 bioreactors of style or family

"A" connected to a transfer line system.

Although the invention has been described in terms of specific embodiments and applications, persons skilled in the art may, in light of this teaching, generate additional embodiments without exceeding the scope or departing from the spirit of the invention described herein. Accordingly, it is to be understood that the drawing and description in this disclosure are proffered to facilitate comprehension of the invention, and should not be construed to limit the scope thereof.

Claims

What is claimed is:

1. A bioreactor arrangement for growing a biomass, the bioreactor arrangement comprising: a source of feedstock; a biomass growth surface; a feedstock transfer arrangement for delivering the feedstock to said biomass growth surface; and a biomass harvesting arrangement for removing the biomass.

2. The bioreactor arrangement of claim 1 , wherein said source of feedstock comprises a pool of feedstock.

3. The bioreactor arrangement of claim 1 , wherein said source of feedstock comprises a pan of feedstock.

4. The bioreactor arrangement of claim 1, wherein said biomass growth surface comprises an absorbent belt.

5. The bioreactor arrangement of claim 1, wherein said biomass growth surface comprises a ribbed belt.

6. The bioreactor arrangement of claim 1 , wherein there is further provided a filter having the characteristic of a semi -permeable membrane having a porosity of less than approximately 30 microns.

7. The bioreactor arrangement of claim 6, wherein said feedstock transfer arrangement comprises a pool of feedstock disposed on one side of said filter.

8. The bioreactor arrangement of claim 7, wherein said pool of feedstock contains sewage.

9. The bioreactor arrangement of claim 1, wherein said biomass growth surface is open to the atmosphere.

10. The bioreactor arrangement of claim 1, wherein said biomass growth surface is closed to the atmosphere.

11. The bioreactor arrangement of claim 10, wherein said biomass growth surface is subjected to a CO₂ enhanced environment.

12. The bioreactor arrangement of claim 10, wherein said biomass growth surface is subjected to a temperature controlled environment.

13. The bioreactor arrangement of claim 1 , wherein there is further provided a light enhancing arrangement.

14. The bioreactor arrangement of claim 13, wherein said light enhancing arrangement comprises a light-focusing lens.

15. The bioreactor arrangement of claim 13, wherein said light enhancing arrangement comprises a lenticular lens.

16. The bioreactor arrangement of claim 13, wherein said light enhancing arrangement comprises a reflective surface.

17. The bioreactor arrangement of claim 16, wherein said reflective surface is a mirror.

18. The bioreactor arrangement of claim 16, wherein there is further provided a tracking arrangement for reorienting said reflective surface in predetermined relation to a moving source of growth light.

19. The bioreactor arrangement of claim 18, wherein said biomass growth surface is oriented substantially vertically.

20. The bioreactor arrangement of claim 1 , wherein said biomass harvesting arrangement comprises a wiper system for automatically harvesting the biomass.

21. The bioreactor arrangement of claim 20, wherein there is further provided an escapement arrangement for the biomass.

22. The bioreactor arrangement of claim 1 , wherein there is further provided a bioreactor support formed of a material that can be sterilized.

23. The bioreactor arrangement of claim 22, wherein said material is stainless steel.

24. The bioreactor arrangement of claim 1, wherein said feedstock transfer arrangement delivers the feedstock to the biomass.

25. The bioreactor arrangement of claim 24, wherein said feedstock transfer arrangement comprises a drip system.

26. The bioreactor arrangement of claim 24, wherein said feedstock transfer arrangement comprises a spray system.

27. The bioreactor arrangement of claim 1, wherein said biomass growth surface is oriented at an angle that is responsive substantially to the elevation of the sun.