Abstract:
A growth module for growing biomass comprising a plurality of growth columns connected together. Each growth column comprises a vertically oriented, hollow, translucent tubular body having input lines for introducing air, gas and nutrients into each column through the top thereof. The growth columns are frictionally mounted upon a bottom manifold that is configured for receiving gravity induced flow of biomass from said plurality of growth columns.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    Benefit is claimed of U.S. Provisional Patent Application Ser. No. 61/233,547, filed Aug. 13, 2009, and as a division of U.S. patent application Ser. No. 12/855,525, filed on Aug. 12, 2010, granted as U.S. Pat. No. 9,534,197, on Jan. 3, 2017. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable 
       BACKGROUND OF THE INVENTION 
     Technical Field 
       [0003]    The present invention generally relates to the field of alternative energy and the efficient creation of alternative energy resources. More specifically, the present invention relates to a biomass production system and apparatus for producing increased yields of biomass. 
       Description of the Related Art 
       [0004]    Society&#39;s practically insatiable appetite for fossil fuel energy is a problem of global proportions and alternative energy sources need to be developed for a variety of reasons. One source of alternative energy can be found in the lipids produced by organisms such as plants, algae, and other photoautotrophic organisms. Photoautotrophic organisms are those that use light to produce energy, most commonly through the photosynthetic process. The lipids are extracted from these organisms through a variety of known processes. Once extracted the lipids are processed for their end use, be it food, pharmaceuticals, or energy products such as biodiesel. In addition, once the lipids are extracted from the organisms, any remaining organic clatter can be burned to produce heat energy. 
         [0005]    Obtaining alternative energy from living organisms presents a challenge. The amount of lipids produced on a per unit basis is relatively small and attaining large yields of lipids requires a significant number of organisms Growing a sufficient amount of organisms requires large amounts of space. The challenge is further increased with organisms that require light to produce energy and grow. For example, algae grown on the surface of a pond will only grow to a total depth of about nine inches because light cannot penetrate any deeper. Algae cannot grow in the darkness below this top layer and the liquid beneath is essentially wasted from a production standpoint. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    The present invention is directed to an efficient system for growing and harvesting a mass of photoautotrophic organisms, or “biomass,” in a liquid medium such as water. The present system not only increases the yield of biomass attainable, it also reduces the energy needs to harvest the biomass. Instead of expending energy to collect biomass from a surface pond, for example, the present invention uses gravitational flow to harvest the biomass. 
         [0007]    The present invention utilizes one or more vertical growth columns to hold a volume of biomass grown in a liquid growth medium. The vertical columns are made from a material that allows light to pass through it so the biomass at all depths of the column can receive light for photosynthesis. As such, the biomass can be grown throughout the column and biomass growth is attained throughout depths that would not be possible in a horizontal system such as a pond. By extension, more biomass can be produced on the same area of land as compared to horizontal systems. 
         [0008]    The verticality of the growth columns also allows the power of gravity to be harnessed for harvesting of the biomass. The biomass is harvested by draining the liquid growth medium—with the biomass contained in it—out of the growth columns. One or more valves located downstream from the gravitational flow of the biomass are opened to initiate a harvest and closed to stop the harvest. A number of vertical growth columns are preferably arranged as a growth module. Each growth module has a bottom manifold for aggregating the output of the columns into a collective output of the growth module. The collective output discharges from the growth module to a harvest tank, a pipeline, or elsewhere for processing. 
         [0009]    The present invention also has certain features to stimulate growth of the biomass so that harvest can be achieved more often. For example, the invention has elements to deliver critical gases such as carbon dioxide to the biomass as well as nutrients for growth. In addition, the overall system contains a shading element that creates diffused light for the biomass to absorb because diffused light provides a better growing environment and further increases production 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  illustrates a perspective view of a site with several systems for growing biomass, with a portion of the shading element of one of the systems cutaway. 
           [0011]      FIG. 2  shows a perspective view of the preferred embodiment of the growth column of the present invention. 
           [0012]      FIG. 3  is an enlarged view of the preferred growth column of the present invention with a portion of the growth column removed. 
           [0013]      FIG. 4  is a cross-section of  FIG. 3  taken along section line  4 - 4 . 
           [0014]      FIG. 5  is a perspective view of the preferred embodiment of a growth module of the present invention and depicts the growth module connected to a harvest tank 
           [0015]      FIG. 6  is an enlarged view of the bottom portion of the growth module depicted in  FIG. 5  and shows the preferred embodiment of a bottom manifold 
           [0016]      FIG. 7  is an enlarged view of the top portion of the growth module depicted in  FIG. 5  and shows the preferred embodiment of a nutrient delivery manifold and a gas delivery manifold. 
           [0017]      FIG. 8  is an enlarge cutaway view of the nutrient delivery manifold and the gas delivery manifold show in  FIG. 7   
           [0018]      FIG. 9  is an enlarged cutaway view of the system in  FIG. 1  showing the shading element rolled up on one side of the structure supporting it. 
           [0019]      FIG. 10  is a perspective view of the system with the shading element and a portion of the structure supporting said shading element removed. material that allows light to pass through it so the biomass at all depths of the column can receive light for photosynthesis. As such, the biomass can be grown throughout the column and biomass growth is attained throughout depths that would not be possible in a horizontal system such as a pond. By extension, more biomass can be produced on the same area of land as compared to horizontal systems. 
           [0020]    The verticality of the growth columns also allows the power of gravity to be harnessed for harvesting of the biomass. The biomass is harvested by draining the liquid growth medium—with the biomass contained in it—out of the growth columns. One or more valves located downstream from the gravitational flow of the biomass are opened to initiate a harvest and closed to stop the harvest. A number of vertical growth columns are preferably arranged as a growth module. Each growth module has a bottom manifold for aggregating the output of the columns into a collective output of the growth module. The collective output discharges from the growth module to a harvest tank, a pipeline, or elsewhere for processing. 
           [0021]    The present invention also has certain features to stimulate growth of the biomass so that harvest can be achieved more often. For example, the invention has elements to deliver critical gases such as carbon dioxide to the biomass as well as nutrients for growth. In addition, the overall system contains a shading element that creates diffused light for the biomass to absorb because diffused light provides a better growing environment and further increases production 
         BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1  illustrates a perspective view of a site with several systems for growing biomass, with a portion of the shading element of one of the systems cutaway. 
           [0023]      FIG. 2  shows a perspective view of the preferred embodiment of the growth column of the present invention. 
           [0024]      FIG. 3  is an enlarged view of the preferred growth column of the present invention with a portion of the growth column removed. 
           [0025]      FIG. 4  is a cross-section of  FIG. 3  taken along section line  4 - 4 . 
           [0026]      FIG. 5  is a perspective view of the preferred embodiment of a growth module of the present invention and depicts the growth module connected to a harvest tank. 
           [0027]      FIG. 6  is an enlarged view of the bottom portion of the growth module depicted in  FIG. 5  and shows the preferred embodiment of a bottom manifold. 
           [0028]      FIG. 7  is an enlarged view of the top portion of the growth module depicted in  FIG. 5  and shows the preferred embodiment of a nutrient delivery manifold and a gas delivery manifold. 
           [0029]      FIG. 8  is an enlarge cutaway view of the nutrient delivery manifold and the gas delivery manifold show in  FIG. 7   
           [0030]      FIG. 9  is an enlarged cutaway view of the system in  FIG. 1  showing the shading element rolled up on one side of the structure supporting it. 
           [0031]      FIG. 10  is a perspective view of the system with the shading element and a portion of the structure supporting said shading element removed. 
           [0032]      FIG. 11  is an enlarged cutaway view of the system with a portion of the shading element removed. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0033]      FIG. 1  illustrates a site containing the preferred embodiment of a system  10  for growing biomass in a liquid growth medium (not shown). As shown, the site contains several systems. The system  10  comprises a structure  12  that supports a shading element  14  with the shading element  14  at least partially surrounding a growth column  16  (see  FIG. 2 ). As will be seen, the growth column  16  holds a liquid growth medium in which the biomass grows. The liquid growth medium is anything that allows growth of the biomass such as water, water combined with nutrients, or other types of liquid media. During growth, the biomass is suspended, mixed, or otherwise combined with the growth medium and, together, the biomass and the liquid growth medium are collectively referred to herein as the “biomass/growth medium mixture.” The preferred biomass is an algae strain known as  chlorella minutissima,  specifically, the UTEX No. 2219 strain from the University of Texas Culture Collection of Algae, but the biomass can be any mass of photoautotrophic organisms. 
         [0034]    As discussed in more detail infra, the system  10  preferably contains a number of growth columns arranged in one or more growth modules. A growth module  18  contains a predetermined number of growth columns arranged in a substantially vertical orientation within the growth module  18  (see  FIGS. 1 &amp; 5 ). 
         [0035]    Referring to  FIG. 2 , the preferred embodiment for the growth column  16  is shown. The growth column  16  has a body  20  that is elongated and hollow. Preferably, the body  20  is a circular cylinder (i.e., a tube); however, other elongated hollow bodies (e.g., a tube with a square side profile, an elliptical cylinder, etc.) could be used. The elongated dimension of the body  20  terminates in a top end  22  and a bottom end  24 , and the force of gravity is directed from the top end  22  to the bottom end  24 . 
         [0036]    The body  20  of the growth column  16  is at least translucent and preferably transparent because light must be able to pass through the body  20  of the growth column  16  to the biomass. Preferably, the body  20  is made from transparent polyvinyl chloride (PVC) but could be made from a number of other materials (e.g., glass). The material from which the body  20  is made may be “doped” with an ultraviolet (UV) stabilizer to reduce the amount of UV light which reaches the biomass and to protect the body  20  against degradation from the UV light. Concerning the biomass, research has shown that excessive ultraviolet radiation contained in ultraviolet light can damage photoautotrophic organisms; therefore, a reduction in ultraviolet light may be desirable depending on the particular biomass inside the growth column  16 . 
         [0037]    Another variant for the body  20  of the growth column  16  is coloration. While the body  20  material may be clear in some embodiments, it could also have a colored tint to it. Adding a colored tint to the body  20  causes filtration of light wavelengths (i.e., colors) because only wavelengths of visible light which match the colored tint will pass through For example, a red-tinted body  20  allows only red wavelengths of light to&#39;pass through the body  20  to the biomass. 
         [0038]    Whether the body  20  has a colored tint to it and the coloration of the tint again depends on the needs of the particular biomass. Research shows that unicellular microorganisms similar to the preferred biomass absorb red light and blue light better than other colors in the visible light spectrum. In addition, tests performed on the preferred biomass suggest that this type of biomass prefers red light because an increased yield was shown when red light is used. 
         [0039]    The size of the body  20  is another factor of the growth column  16  that can be varied to promote optimal light absorption and therefore increase yield. The size of the side profile affects the amount of light which penetrates to the center of the body  20  and thus, the overall photosynthetic efficiency of the biomass in the growth column  16 . If the side profile is too large, not enough light will reach the center of the biomass, thus decreasing optimal photosynthesis. 
         [0040]    The preferred size of the side profile varies again according to the needs of the particular biomass, as well as the shape of the side profile. In the preferred embodiment of the growth column  16  with the preferred biomass, the side profile of the body  20  has a six inch diameter. Research concerning algae photosynthesis combined with tests directed to the present system  10  lead to the conclusion that optimal light penetration is achieved from the circumference of the body  20  up to three inches deep. As a result, the circular side profile of the preferred body  20  has a three inch radius, thus making the preferred body six inches in diameter. 
         [0041]    The top end  22  of the body  20  is open and connected to the top end  22  of the body  20  is a top piece  26  which covers the opening. As shown in  FIGS. 3 &amp; 4 , the top piece  26  is preferably a separately manufactured piece that the top end  22  of the body  20  fits within. Alternatively, the top piece  26  could be separately manufactured and fit within the opening at the top end  22  of the body  20 , or, the top piece  26  may even be manufactured as part of the body  20 . 
         [0042]    The top piece  26  preferably connects to the top end  22  of the body  20  with a friction fit and not an interference fit. Although an interference fit may be used in some embodiments, the preferred embodiment does not utilize such a fit because of their tendency to become stuck or frozen together, which creates difficulty when trying to disconnect the connection. Unless otherwise noted, all connections in the growth column  16  and/or the growth module  18  are preferably a friction fit. 
         [0043]    A friction fit is achieved when the inner perimeter of the top piece  26 , or an element within the top piece  26 , contacts the top end  22  of the body  20  but neither the top end  22  nor the body  20  are deformed. During installation of the top piece  26  on the top end  22 , the top piece  26  slides adjacent to the outer perimeter of top end  22  but neither perimeter is deformed. In order to achieve a friction fit, at least a portion of the inner perimeter of the top piece  26 —or elements therein—is shaped substantially similar to and slightly larger than the outer perimeter of the top end  22  of the body  20 . For example, the inner circumference of the top piece  26  is slightly larger that the outer circumference of the top end  22  in the preferred growth column  16 . 
         [0044]    Preferably, the friction fit connection is sealed from the outside environment with a sealing apparatus. As shown in  FIG. 4 , an elastomeric O-ring  28  sitting within a groove  30  is the preferred sealing apparatus for the various connections in the invention. The elastomeric O-ring  28  is deformed and presses against a connecting surface to seal the connection and creates friction. For example, the O-ring  28  is deformed by the outer perimeter of the top end  22  of the body  20  when the top piece  26  is installed on the top end  22 , thereby causing the O-ring  28  to press against the outer perimeter of the top end  22  and the groove  30  in the inner perimeter of the top piece  26 . It should be noted, however, that other sealing apparatuses (e.g., an elastomeric sealing boot) may be used to seal a friction fit connection. 
         [0045]    The preferred embodiment of the top piece  26  has three main parts: atop reducer  32 , a top cap  34 , and a spacer  36 . The top reducer  32  decreases the size of the inner perimeter of the top piece  26  as it extends away from the body  20  so that, for example, the inner circumference of the top piece  26  is reduced from approximately six inches in diameter to four inches in diameter as the top piece  26  extends away from the preferred body  20 . The spacer  36  connects to the reduced dimension of the top reducer  32  at one end and connects to the top cap  34  at its other end. The top cap  34  terminates the top piece  26 . 
         [0046]    The top piece  26  helps prevent entry of unwanted items such as harmful bacterial strains or parasitic matter such as fungi into the biomass/growth medium mixture and also it helps prevent evaporation of the liquid growth medium from the growth column  16 . It is not required, however, that the top piece  26  create an absolute airtight or even watertight seal. In fact, the top piece  26  has different passageways through it for introducing items to the biomass/growth medium mixture in the growth column  16 , as discussed infra. 
         [0047]    The bottom end  24  of the body  20  also has a bottom piece  38  connected to it. The bottom piece  38  may be a separately manufactured piece that is installed on the bottom end  24  or may be manufactured as part of the body  20 . Preferably, the bottom piece  38  is a separately manufactured piece that is connected to the bottom end  24  of the body  20  with the friction fit and O-ring  28  like the top piece  26 , but, unlike the top piece  26 , the connection of the bottom piece  38  to the body  20  needs to be sufficiently sealed to prevent liquid growth medium from leaking out of the growth column  16 . In its preferred form, the bottom piece  38  is a reducer and its inner perimeter decreases as it extends away from the body  20 . So, for example, in the preferred embodiment of the growth column  16 , the inner perimeter of the bottom piece  38  decreases from approximately six inches down to four inches. Alternatively, the bottom piece  38  may provide a greater or smaller size reduction ratio or no size reduction at all. 
         [0048]    The biomass is harvested through gravity and travels through the bottom piece  38  toward its ultimate destination. When the growth column  16  is used as a standalone, the bottom piece  38  connects to a valve (not shown) that can be opened and closed to activate flow of the biomass/growth mixture out of the bottom piece  38 . When the valve is opened, gravity causes the biomass/growth medium mixture to travel from the body  20  of the growth column  16  through the bottom piece  38  and out of the valve, thereby emptying at least a portion of the biomass/growth mixture from the growth column  16 . The valve is thus located downstream of the biomass/growth medium mixture flow out of the bottom piece  38 . When the growth column  16  is one of many growth columns within the growth module  18 , the bottom piece  38  connects through a spacer  40  to a bottom manifold  42  (see  FIGS. 5 &amp; 6 ) and the downstream valve is within the bottom  42  manifold and/or elsewhere, as is discussed in more detail infra. 
         [0049]    Extending from the top end  22  of the body  20  toward the bottom end  24  of the body  22  are a gas delivery line  44  and a nutrient delivery line  46 . Preferably, the gas delivery line  44  and the nutrient delivery line  46  extend through and protrude from the top piece  26  of the growth column  16 ; however, they could enter into the cavity of the body  20  in another location other than at the top end  22  (e.g., through the side of the body  20 ). Within the cavity of the body  20 , the gas delivery line  44  preferably terminates near the bottom end  24  of the body  20  while the nutrient delivery line  46  preferably terminates closer to the top end  22  of the body  20 . In the preferred embodiment, the gas delivery line terminates approximately two inches from the bottom end  24  of the body  20  and the nutrient delivery line  46  terminate approximately four to six inches from the top end  22  of the body  20 . 
         [0050]    The gas delivery line  44  delivers predetermined types of gas to the interior of the growth column  16 . The gas is forced into the gas delivery line  44  and delivered to the interior of the growth column  16  with pressure. Often, the gas will come from a pressurized storage vessel such as a gas cylinder; however, other means of delivery (e.g., a compressor) could be used. Which gas and the amount of gas delivered typically depends on the particular needs of the biomass growing inside the growth column  16  and, usually, increasing the yield of biomass is the main factor driving gas selection and amount. However, other factors may come into play. For example, a gas may be selected to kill the biomass if a harmful bacterium has been introduced and eradication is desired. 
         [0051]    One type of gas that is needed by all types of photoautotrophic organisms is carbon dioxide or CO 2 . Carbon dioxide is an integral component of photosynthesis. It combines with water (H 2 O) in the presence of light to form glucose (C 6 H 12 O 6 ) according to the following equation: 
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         [0000]    The resulting glucose is ultimately absorbed by the organism and converted into cellular constituents, thus allowing growth of the organism. 
         [0052]    Delivery of CO 2  through the gas delivery line  44  promotes photosynthesis and thus increases the yield of biomass. The amount of CO 2  delivered to obtain optimal yield can be correlated to the particular needs of the biomass using growth factors such as the pH level of the growth medium inside the growth column  16 . The pH level is measured with a pH meter and adding CO 2  makes the growth medium more acidic. With the preferred biomass, for example, it has been found that 7.4 pH is the desired, average pH level of the growth medium in the growth column  16 . To attain this level, pure CO 2  is delivered to the biomass/growth medium mixture via the gas delivery line  44  at a rate of 20 Liters per minute for 2-5 minutes, until it reaches 6.7 pH. Once the desired pH is reached, the gas delivery is shut off. As the biomass consumes CO 2  during photosynthesis, the growth medium becomes more basic and requires additional CO 2 . It has been found that delivering the CO 2  at the above described rates twice a day obtains the desired average. 
         [0053]    The gas delivery process can be automated or manually controlled, depending on the complexity of the system  10 . For example, valves (not shown) placed between the gas source and the gas delivery line  44  could be manually controlled or automated. Manual control requires periodic testing of the environment within the growth column  16  and manually activating (e.g., physically turning a valve, pressing a button, etc.) the gas delivery based on these values. In an automated system, the delivery rates would be preset into a computer or tied to sensors, such as the pH meter discussed above, that provide real-time feedback of the growing conditions. 
         [0054]    Uniform distribution of the gas delivered to the biomass/growth medium mixture is desirable. To help achieve this goal, the gas delivery line  44  preferably has a weight  48  attached to it just above its termination point within the body  20 . The weight  48  helps hold the termination point of the gas delivery line  44  near the bottom end  24  of the body  20 . Having the termination point near the bottom end  24  allows the gas to bubble upward through the biomass/growth medium mixture in the body  20  of the growth column  16 . In the preferred embodiment the weight  48  is a circular cylinder weight which weighs 42.6 grams, has a 1⅛″ diameter, and 1¾″ height. 
         [0055]    To further increase uniform distribution of gas throughout the biomass/growth medium mixture, the gas delivery line  44  also preferably has a dispersion element  50  connected at its termination point in the body  20 . The dispersion element  50  is a porous structure which receives gas from the gas delivery line  44 , disperses the gas throughout its pores, and releases the gas from its pores into the biomass/growth medium mixture. The size of the pores in the dispersion element  50  affects the size of gas bubbles released from it, with gas bubbles tending to be smaller in a dispersion element  50  with smaller pores. The preferred dispersion element  50  is a sintered brass product with a ten micron filtration pore size; however, it could be a variety of other products such as a ceramic frit or even a sponge. 
         [0056]    The nutrient delivery line  46  delivers liquid-based nutrients and other liquid-based items to the interior of the growth column  16 . Liquid-based nutrients fertilize growth of the biomass. The nutrients are suspended, mixed, or otherwise combined in a liquid such as the growth medium or some other type of liquid and flow through the nutrient delivery line  46 . In the preferred embodiment, the liquid/nutrient combination discharges from the nutrient delivery line  46  near the top end  22  of the body  20  and gravity helps the liquid/nutrient combination flow from the top end  22  of the body  20  toward the bottom end  24 . 
         [0057]    Nutrients can be a variety of substances such as, for example, nitrates, ammonia, phosphorous, and potassium. The exact nutrient composition depends on the needs of the particular biomass taking into account factors such as the type of biomass, the growth phase of the biomass, and the desired production of lipids from the biomass. For example, the nutrient needs of the biomass may vary depending on whether the biomass is being initially inoculated into the growth column  16 , whether the biomass is being maintained between harvests, or whether the biomass is being replenished after harvest. 
         [0058]    In addition to nutrients, the nutrient delivery line  46  may be used to fill the growth column  16  with the biomass/growth medium mixture or the growth medium alone. For example, at initial inoculation, the growth column  16  may be filled with a predetermined ratio of liquid growth medium and biomass by pumping the liquid growth medium and biomass through the nutrient delivery line  46 . The nutrient delivery line  46  can also be used to replenish the growth column  16  with liquid growth medium or with additional biomass/growth medium mixture after harvest. 
         [0059]    Also shown in  FIG. 4 , the top piece  26  also has an air delivery passage  52  extending through it. The air delivery passage  52  is a passageway that allows air to travel from the environment outside the growth column  16  to the interior of the growth column  16  and vice versa. Air enters the growth column  16  through the air delivery passage  52  when the biomass/growth medium mixture is harvested and without it, a vacuum would be formed within the growth column  16 . In this regard, air travels through the air delivery passage  52  to replace the volume of space formerly occupied by the biomass/growth medium mixture during harvest. Similarly, air passes from the interior of the growth column  16  back to the environment outside the growth column  16  as matter (e.g., nutrients, growth medium, etc.) is introduced to the interior of the growth column  16 . 
         [0060]    Preferably, a filtering element  54  is located on the top piece  26  where the outside air enters into the air delivery passage  52  so that the outside air must travel through the filtering element  54  prior to entering the air delivery passage  52 . Alternatively, the filtering element  54  could be located elsewhere, such as inside the growth column  16  between the air delivery passage  52  and the biomass/growth medium mixture. The filtering element  54  prevents unwanted objects from being introduced to the biomass/growth medium mixture and is chosen according to desired filtration requirements. The preferred filtering element  54  is the same as the preferred dispersion element  50  discussed above and provides a ten micron filtration. 
         [0061]    Turning now to  FIG. 5 , the preferred embodiment of the growth module  18  containing numerous growth columns is shown. Each growth column  16  in the growth module  18  is oriented in a substantially vertical direction and connects to the bottom manifold  42 . The bottom manifold  42  is structurally configured to receive the biomass/growth medium mixture from of each growth column  16  in the growth module  18  and to aggregate the collected biomass/growth medium mixture into a collective output (not shown) of the growth module  18 . The collective output of the growth module is discharged from the bottom manifold  42  at one or more outlet ports, as discussed below. 
         [0062]    The design of the bottom manifold  42 , which can be varied from that shown, dictates the arrangement and number of growth columns in the growth module  18 . In  FIG. 6 , the preferred embodiment of the bottom manifold  42  is shown for when collective output of an individual growth module  18  is desired. As shown, each growth column  16  is aligned in a manifold row  56  with nine individual growth columns per each manifold row  56 . There are five manifold rows per each growth module  18 , thereby making a total of forty-five individual growth columns in the preferred growth module  18 . The body  20  of each growth column  16  is a minimum distance of 2¾″ away from the body  20  of the closest growth columns in the growth module  18 , however, this distance could be reduced further depending on the availability of custom manufactured parts. 
         [0063]    The bottom piece  38  of each growth column  16  in the preferred growth module  18  connects to the manifold row  56  through either an upper T-joint  58  or an end T-joint  60 , depending on the location of the growth column  16  in the growth module  18 . Each manifold row  56  is the same length as the other manifold rows in the growth module  18 , is aligned substantially parallel to the other manifolds rows in the growth module  18 , and is in the same general horizontal plane as the other manifold rows in the growth module  18 . The endpoints of each manifold row  56  are also commonly aligned with the endpoints of the other manifold rows in the growth module  18 , and, if a plane were laid across the outer edge of the end T-joints at one side of the growth module  18  the plane would touch the outer edge of each end T-joint  60  on that side. 
         [0064]    Each upper T-joint  58  in each manifold row  56  is connected in a series with the other upper T-joints in that manifold row  56  with a spacer  62  such that the two aligned openings of each upper T-joint  58  in that manifold row  56  are horizontal. The two aligned openings of the upper T-joint  58  are the two openings of the joint that form a straight passageway through the joint. The other opening of the upper T-joint  58 , which is the non-aligned opening, faces vertically upward, toward the individual growth column  16  above the upper T-joint  58 . The bottom piece  38  of each growth column  16  that is above an upper T-joint  58  connects to the non-aligned opening of its respective upper T-joint  58  through the spacer  40  (see  FIG. 4 ). 
         [0065]    Each manifold row  56  terminates at the end T-joint  60 . The non-aligned opening of the end T-joint  60  faces inward, toward the interior of the growth module  18  and both ends of each manifold row  56  are connected to the non-aligned end of their respective end T-joint  60 . The two aligned openings of each end T-joint  60  are vertically aligned with the individual growth column  16  above that end T-joint  60 . Each end T-joint  60  has an upwardly facing aligned opening  64  and a downwardly facing aligned opening  66  that together form a straight passageway through the end T-joint  60 . The upwardly facing aligned opening  64  faces toward the bottom piece  38  of the individual growth column  16  above that end T-joint  60 , while the downwardly facing aligned opening  66  faces away from the growth column  16  above that end T-joint  60 . The bottom piece  38  of each growth column  16  that is above an end T-joint  60  connects to the upwardly facing aligned opening  64  of its respective end T-joint  60  through the spacer  40  (see  FIG. 4 ). 
         [0066]    The downwardly facing aligned opening  66  of each the end T-joint  60  in the preferred bottom manifold  36  faces toward a corresponding lower T-joint  68  located below that individual end T-joint  60 . Each end T-joint  60  connects to the non-aligned opening of its respective corresponding lower T-joint  68  through a spacer  68 . Because each manifold row  56  terminates with the end T-joint  60  at its two endpoints, two different series of corresponding lower T-joints are formed: a first series  72  of lower T-joints along the endpoints of the manifold rows at one side and a second series  74  of lower T-joints along the endpoints of the manifold rows at the other side. 
         [0067]    The two aligned openings of each lower T-joint  68  in a series are aligned with the other aligned openings of the other lower T-joints in that series so that a straight passageway through the lower T-joints is formed. The aligned openings between the lower T-joints in the first series  72  are connected via spacers and the outer lower T-joints in the first series  72  are extended to form a first bottom conduit  76 . Similarly, the aligned openings between the lower T-joints in the second series  74  are connected via spacers and the outer lower T-joints in the second series  74  are extended to form a second bottom conduit  78 . 
         [0068]    The first and second bottom conduits  76  and  78 , respectively, in the preferred bottom manifold  42  are substantially parallel to each other. Both also extend horizontally in a direction transverse to the direction of each manifold row  56  extend past the vertical plane formed by the outer edge of the body  20  of the growth columns. 
         [0069]    The endpoints of the first and second bottom conduits  76  and  78  connect to each other, as shown in  FIGS. 5 &amp; 6  when the preferred bottom manifold  42  is designed to provide output of each growth module  18  on an individual basis. Alternatively, the endpoints of the first and second bottom conduits  76  and  78  in the growth module  18  may be the outlet ports of the bottom manifold and may connect to the endpoints of other first and second bottom conduits from other growth modules in the system  10 . In  FIGS. 5 &amp; 6 , the endpoint of the first bottom conduit  76  that is on the same side of the growth module  18  connects to the corresponding endpoint of the second bottom conduit  78  on that side through a connecting piece  80 . The end of the first bottom conduit  76  that is on the other side of the growth module  18  connects to the corresponding end of the second bottom conduit  78  on that side with a connecting piece  82  that is only partially shown in  FIG. 6 . Although only partially shown, the connecting piece  82  has the same structure as connecting piece  80 . Preferably connecting pieces  80  and  82  extend between elbow joints  84  so that a rectangle is formed between the first bottom conduit  76 , the second bottom conduit  78 , and the connecting pieces  80  and  82 . 
         [0070]    Each of the connecting pieces  80  and  82  preferably has an outlet port configured as an outlet T-joint  86  disposed on it. The outlet T-joint  86  is centered between the connection of the first bottom conduit  76  and the second bottom conduit  78 . The aligned openings of the outlet T-joint  86  face either the first or second bottom conduits  76  and  78  and the non-aligned opening of the outlet T-joint  86  faces away from the growth module  18 . Preferably, there are two shutoff valves  88  in each of the connecting pieces  80  and  82  with one being located between the outlet T-joint  86  and the first bottom conduit  76  and the other being located between the outlet T-joint  86  and the second bottom conduit  78 . Although the outlet T-joint  86  in each of the connecting pieces  80  and  82  could be located elsewhere, centering the outlet T-joint  86  promotes equal draining of the biomass/growth medium mixture during harvest. In addition, although a single outlet T-joint  86  could be used as the outlet port in the bottom manifold  42  two outlet T-joints are preferred for the same reason. 
         [0071]    The non-aligned opening of each outlet T-joint  86  connects to a discharge manifold  90 . As shown in  FIG. 6 , the discharge manifold  90  is configured to aggregate the collective output of the growth module  18  from each outlet T-joint  86  in the bottom manifold  42  when the collective harvest of each individual growth module  18  is desired; however, when the growth module  18  is connected to the bottom manifold  42  of other growth modules, the discharge manifold  90  may be configured to aggregate the collective output of the connected growth modules, as discussed infra. 
         [0072]    Referring to the bottom manifold  42  in  FIG. 6 , the discharge manifold  90  extends from the non-aligned opening of each outlet T-joint  86  around half the perimeter of the rectangle formed by the first and second bottom conduits  76  and  78  and connecting pieces  80  and  82 . The two sides of the discharge manifold  90  come together at a discharge T-joint  92  preferably at the center of the discharge manifold  90 . The non-aligned opening of the discharge T-joint  92  connects to a discharge line  94 . Referring back to  FIG. 5 , the discharge line  94  contains a discharge valve  96  and leads to a harvest tank  98  in the embodiment shown, however, the discharge line  94  could alternatively lead to a pipeline  100  (see  FIG. 10 ) or elsewhere. 
         [0073]    Similar to the individual growth column  16  discussed above, harvesting the biomass from the growth module  18  is preferably achieved through the effect of gravitational force on the biomass/growth medium mixture. Gravitational force on the biomass/growth medium mixture in the body  20  of each growth column  16  pulls the biomass/growth medium mixture downward toward the open bottom piece  38  of the growth column  16  into the bottom manifold  42 . The bottom manifold  42  collects the biomass/growth medium mixture output from each growth column  16  in the growth module  18  and aggregates the growth columns&#39; the collective output for transfer to the discharge manifold  90 . The discharge manifold  90  collects the biomass/growth medium mixture output from the bottom manifold  42  and aggregates the bottom manifold&#39;s collective output for transfer to the discharge line  94 . 
         [0074]    How the bottom manifold  42  collects and aggregates the collective output of the biomass/growth medium mixture from the growth columns depends on the particular design of the bottom manifold  42 . In the preferred bottom manifold  42 , where the biomass/growth medium enters into the manifold depends on the location of the growth column  16  in the growth module  18 . Gravity forces the biomass/growth medium mixture into either an upper T-joint  58  or an end T-joint  60 . Gravitational force on the biomass/growth medium mixture in each growth column  16  above an upper T-joint  58  also forces biomass/growth medium mixture out of the manifold row  56  into the non-aligned opening of one of the end T-joints for that manifold row  56 . Each end T-joint  60  receives biomass/growth medium mixture from both its respective manifold row  56  and the growth column  16  above that end T-joint  60 . The biomass/growth medium mixture travels through the end T-joint  60 , out of its downwardly facing aligned opening  66 , and into the non-aligned opening of its corresponding lower T-joint  68 . In the lower T-joint  68 , the biomass/growth medium mixture is forced along the first and second bottom conduits  76  and  78  and into one of the connecting pieces  80  and  82 . In the connecting pieces  80  and  82 , the biomass/growth medium mixture is forced into and out of the outlet T. Joint  86  to the discharge manifold  90  for transfer to the discharge line  94 . 
         [0075]    Initiating flow of the biomass/growth medium mixture from the growth module  18  to its ultimate destination is controlled by one or more valves located downstream from the flow of the biomass/growth medium mixture (e.g., the discharge valve  96 , the shut-off valves  88 , etc.). When the downstream valve is opened the biomass/growth medium mixture flows out of the growth module  18 . Preferably, gravitational force alone drives the flow of the biomass/growth fluid mixture from the growth module  18  to its ultimate destination; however, this flow may be aided by other forces (e.g., pumps) if necessary. 
         [0076]    When harvesting, it has been found that approximately ten to thirty percent of the biomass/liquid growth medium mixture is preferably removed from each growth column  16 . Although the configuration of the growth module  18  would allow all of the biomass/growth medium mixture to be removed from the growth columns, such a result is not desired. Instead, the portion of the biomass/growth medium mixture removed from each tube is replenished with additional liquid growth medium and/or biomass/liquid growth medium mixture and the remaining biomass/growth medium mixture in the growth columns after harvest regenerates quicker and there is less of a lag time between harvests. 
         [0077]    Turning now to  FIG. 7 , the top of the preferred growth module  18  is shown. As previously discussed, the top piece  26  of each growth column  16  has the gas delivery line  44  and the nutrient delivery line  46  protruding from it. With forty-five growth columns in the preferred growth module  18  there are forty-five gas delivery lines and forty-five nutrient delivery lines per growth module  18 . Each gas delivery line  44  in the growth module  18  connects to a gas delivery manifold  102  that preferably extends through the growth module  18  near the top piece  26  of each growth column  16 . The gas delivery manifold  102  is connected to a gas input line  104  from a gas source (not shown) and connects to the gas delivery line  44  of each growth column  16  in the growth module  18 . 
         [0078]    A portion of the preferred gas delivery manifold  102  from  FIG. 7  is cut away and shown in  FIG. 8 . As shown in  FIGS. 7 &amp; 8 , the preferred gas delivery manifold  102  has a gas baseline  106  extending along one side of the growth module  18 , at or near the top of the growth module  18 . The gas input line  104  connects to the gas baseline  106  at the midpoint of the gas baseline  106 . Gas delivery branches  108  connect to the gas baseline  106  at various points and extend in a straight line from the gas baseline  106  toward the opposite side of the growth module  18 , between the top pieces of the growth columns. As such, the gas delivery branches  108  are parallel to each other. 
         [0079]    In the preferred gas delivery manifold  102 , the gas input line  104  brings gas from a gas source (not shown) to the gas baseline  106 . The gas travels from the gas baseline  106 , through the gas delivery branches  108 , to the gas delivery line  44  of each growth column  16  and ultimately to the biomass/growth medium mixture therein. It should be noted that the gas source can be a permanent or temporary storage medium (e.g., a tank) or gas could be piped in directly from a gas producing source (e.g., CO 2  segregated from coal-fired power plant emissions introduced directly to the gas input line  104 ). In addition, multiple gas input lines could be connected to the gas delivery manifold  102 . 
         [0080]    Similar to the gas delivery lines, the nutrient delivery line  46  of each growth column  16  connects to a nutrient delivery manifold  110  that preferably extends through the growth module  18  near the top piece  26  of each growth column  16 . The nutrient delivery manifold  110  is connected to a nutrient input line  112  from a source (not shown) and connected to the nutrient delivery line  46  of each growth column  14  in the growth module  18 . 
         [0081]    The preferred nutrient delivery manifold  110  is similar in form to the preferred gas delivery manifold  102  and a cutaway portion from  FIG. 7  is shown in  FIG. 8 . The preferred nutrient delivery manifold  110  has a nutrient baseline  114  extending along one side of the growth module  18 , at or near the top of the growth module  18 . Preferably, the nutrient baseline  114  extends along the side of the growth module  18  opposite the side of the growth module  18  where the gas baseline  106  extends. The nutrient input line  112  connects to the nutrient baseline  114  at the midpoint of the nutrient baseline  114 . Nutrient delivery branches  116  connect to the nutrient baseline  114  at various points and extend in a straight line from the nutrient baseline  114  toward the opposite side of the growth module  18 , between the top pieces of the growth columns. As such, the nutrient delivery branches  116  are parallel to each other in the preferred growth module  18 . 
         [0082]    In the preferred nutrient delivery manifold  110 , the nutrient input line  112  brings liquid-based materials from the source (not shown) to the nutrient baseline  114 . The liquid-based materials travel from the nutrient baseline  114 , through the nutrient delivery branches  116 , to the nutrient delivery line  46  of each individual growth column  16  and ultimately to the biomass/growth medium mixture therein. The source for the nutrient input line  112  can be a permanent or temporary storage medium or the liquid-based materials could be piped in directly from a source that produces the desired liquid-based materials. In addition, multiple nutrient input lines could be connected to nutrient delivery manifold  110 . 
         [0083]    Now that preferred growth module  18  has been explained the importance of the friction fit discussed supra should become apparent when one considers the necessity of repair. If, for example, the body  20  of one growth column  16  in the growth module  18  is damaged and has to be replaced, the disconnectability of the friction fit facilitates repair. If the connection between the damaged body  20  and the bottom piece  38  (see  FIG. 4 ) were glued or otherwise permanently affixed, the damaged body  20  of the growth column  16  could not be disconnected and alternative measures for repair would be required. On the other hand, the damaged body  20  in the preferred growth column  16  with the friction fit could be easily removed from the bottom piece  38 . The same rationale applies to repair of other damaged components in the growth module  18  which connect with the friction fit. 
         [0084]    As mentioned, the growth module  18  may be one of many in the system  10 . It is envisioned that large-scale biomass growing systems will have one or more growth modules partially surrounded by the shading element  14 , as shown for example in  FIG. 1 . 
         [0085]    In the system  10 , the shading element  14  at least partially surrounds, but does not necessarily touch, one or more growth columns and in large-scale biomass growing operations one or more growth modules. Preferably, the shading element  14  partially surrounds the growth column  16  or the growth module  18  such that sunlight must pass through the shading element  14  prior to contacting the growth column  14  or growth module  18  for the majority of daylight hours. 
         [0086]    The shading element  14  is the material covering the tops and sides of the preferred structure  12  shown in  FIG. 1 , not the structure  12  itself. The structure  12  supports the shading element  14 . Any number of structures, other than that shown in  FIG. 1 , could support the shading element  14  and hold it in relation to the growth columns and/or growth modules. For example, the shading element  14  could be supported and held by posts so that the overall structure resembles more of a tent-like structure. 
         [0087]    The shading element  14  is made from any material that diffuses direct sunlight. In the preferred embodiment, the shading element  14  is formed from a weave of white polypropylene material that has been treated with an ultraviolet stabilizer to resist UV degradation. The weave is constructed with a flat warp and a round pick, with the flat warp being woven over and under the round pick. Weaving the flat warp over and under the round pick causes peaks and valleys in the flat warp. Direct sunlight hits peaks and valleys of the warp and is partially reflected, partially absorbed, and partially transmitted through the shading element  14 . The sunlight that passes through (i.e., transmitted) is scattered in all different directions, thereby eliminating all shadows on the side of the shading element  14  opposite the sun. 
         [0088]    The elimination of shadows by the shading element  14  promotes uniform light delivery to the biomass in the growth column  16 . In this regard, the back side of the growth column  16  is not shaded off by the side of the growth column  16  facing toward the sun. In addition, as it applies to the growth module  18 , the growth columns at the interior of the growth module  18  are not shaded off by the outer growth columns closer toward the sun. 
         [0089]    The diffuse light from the shading element  14  also promotes photosynthesis of the biomass at all depths of the growth column  16 , thereby increasing the yield attained by the system  10 . In this regard, the biomass receives similar amounts of diffused light regardless of location of the biomass in the growth column  16 . Moreover, light diffusion by the shading element  14  increases the photosynthetic efficiency of the biomass by reducing photoinhibition. Photoinhibition occurs when certain proteins involved in the photosynthetic process are damaged, for example by direct sunlight, and normal photosynthetic processes are reduced. 
         [0090]      FIG. 9  shows a portion of the preferred structure  12  and illustrates a component that is preferably present in the system  10 . As shown, a portion of the shading element  14  extending from one side of the structure  12  has been rolled up around a crankshaft  118 . The crankshaft  118  extends along the bottom edge of the shading element  14  when the shading element  14  is unrolled. The crankshaft  118  has a handle  120  at both of its ends and the applicable portion of the shading element  14  is rolled from the ground up by turning the handle  120  at each end. Once this portion of the shading element  14  is rolled up, the handle  120  is secured to the building with a rope  122  or some other fastening device. The shading element can be rolled up in this manner to provide ventilation. In addition,  FIG. 9  shows a door  124  and a vent  126  that are also present on the preferred structure  12 . 
         [0091]    Within the diffused light of the shading element  14 , the arrangement and number of growth columns and/or growth modules in the system  10  is a design choice.  FIGS. 1 &amp; 10 , which have a portion of the shading element  14  and a portion of the preferred structure  12  removed for illustration purposes, show two possible arrangements of growth modules in the system  10 . In  FIG. 1 , the numerous growth modules individually connect to a common discharge line  128  through their bottom manifold  90  and the common discharge line  128  feeds into the single harvest tank  98  in the system  10 . Alternatively, the numerous growth modules in  FIG. 1  could each have its own harvest tank  98  as in  FIG. 5 . As shown in  FIG. 10 , the numerous growth modules individually connect to the common discharge line  128  through their bottom manifold  90  and the common discharge line  128  connects to the pipeline  100  outside the structure  12 . 
         [0092]    Another possible arrangement of growth modules in the system  10  is to connect them as a chain (not shown) with one or more growth modules linked via their bottom conduits. In this regard, an endpoint of the first and second bottom conduits  76  and  78  of one growth module  18  (see  FIG. 6 ) are connected to a corresponding endpoint of the first and second bottom conduit  76  and  78  of an adjacent growth module  18 . Any number of growth modules could be linked in this way and the discharge manifold  90  would collect and aggregate the collective output of all the growth modules in the chain, for delivery of the collective output of the chain to the discharge line  94 . In this regard, the outermost endpoints of the first and second bottom conduits  76  and  78  of the first growth module  18  in the chain could be connected with the connecting piece  80  (see  FIG. 6 ) and the outermost endpoints of the first and second bottom conduits  76  and  78  of the last growth module  18  in the chain could be connected with the connecting piece  82  (see  FIG. 6 ). The discharge manifold  90  would connect to the outlet port (i.e., outlet T-joint  86 ) of the connecting pieces  80  and  82  to aggregate the collective output of the chain of growth modules. Again, the discharge line  94  would then deliver the collective output of the chain to a desired location such as the harvest tank  98 , the pipeline  100 , or elsewhere. 
         [0093]    Alternatively, each growth module  18  in the chain of growth modules could be connected such that a single outlet port (e.g., outlet T-joint  86  in  FIG. 6 ) connects to the a corresponding single outlet port of the adjacent growth module  18 . 
         [0094]      FIG. 11  shows the same portion of the preferred structure  12  in  FIG. 9 ; however, a portion of the shading element  14  has been removed to reveal additional components of the system  10  which may be present. As shown, a temperature control system  130  is in place under the removed portion of the shading element  14 . The temperature control system  130  regulates the temperature surrounding the growth columns by misting groundwater or some other type of non-toxic liquid into the environment around and on the growth columns. The temperature surrounding the growth columns either rises or fall based upon the temperature of the liquid coming from the temperature control system  130 . 
         [0095]    The temperature of the environment surrounding the growth columns affects the interior temperature of the growth column  16  and the production rate of the biomass therein. The biomass and/or the growth column  16  can be negatively affected if the temperature gets too hot or too cold within the system  10 . For example, freezing temperatures can kill some types of biomass or even worse yet, may cause failure of the growth column  16  if the liquid growth medium freezes and expands to a point that fractures the growth column  16 . Conversely, if the temperature of the growth column gets too hot the biomass may denature and not be able to perform vital metabolic processes. 
         [0096]    If has been found that the preferred biomass can be grown in temperatures ranging from approximately 14° Celsius to 32° Celsius; however, the temperature optimally should be kept between 20° Celsius and 30° Celsius. To maintain optimal growing temperatures, a temperature feedback mechanism (not shown) is preferably in place within the system  10 . The temperature feedback mechanism is coupled to a thermometer (not shown) that provides real-time measurement of the temperature. The thermometer may be positioned to measure (1) the temperature of the biomass/growth medium mixture within the growth column  16 ; (2) the temperature of the environment around the growth column  16 ; or, (3) the temperature of both. The temperature control system  130  is preferably automated so that it activates based on the data from the temperature feedback system however it could be manually activated. 
         [0097]    Concerning automation, it should be noted that other processes within the preferred system  10  are automated through multiple feedback systems (not shown) controlled by a processor (not shown). The processor receives and processes real-time data from sensors within the system  10  and controls the operation of various functions within the system based on that information. For example, the delivery of CO 2  can be controlled by real-time feedback of information about the pH level within the growth column  16  as discussed supra. Other examples of automation are activation of the temperature control system  130  based on input from thermometers as well as the delivery of nutrients based on real-time testing of nutrient composition within the growth column  16 . 
         [0098]    As for automated harvesting of the biomass/growth medium mixture, this can be initiated by electronically-operated valves which open at preset times, according to known growth rates of the biomass. The amount of biomass/growth medium mixture extracted from the growth column  16  is also preferably controlled via a feedback system, with feedback coming from sensors within the growth column  16  that measure the fluid level of biomass/growth medium mixture in the growth column  16 . Once the biomass/growth medium mixture gets to a certain point in the growth column  16 , the sensors notify the processor and the processor tells the electronically-operated downstream valves to close. The processor then instructs one or more valves (not shown) to be opened and the nutrient delivery line  46  re-inoculates the growth column  16  with the proper amount and percentage biomass/growth medium mixture. 
         [0099]    Finally, although not shown in  FIG. 11 , artificial lights could also be present in the system  10  to provide increased light for growth of the biomass. Artificial lighting can be used to increase the exposure of the biomass to light that is otherwise not available naturally as, for example, during winter months when daylight is shortened. Increased exposure to light promotes photosynthesis and ultimately increases yield. As with the other systems above, light delivery of artificial light may be on a preset schedule controlled by the processor or could also be part of an automated system that relies on feedback from light sensors. 
         [0100]    On a global scale, it is anticipated that numerous biomass growing systems would be arranged on a piece of land so that the entire site is dedicated to the production of biomass (see  FIG. 1 ). Preferably, the biomass growing systems would be arranged on the site so that the greatest number of systems fit on the site, thereby optimizing the production of biomass. For example, the biomass growing systems on the site could be arranged into a grid pattern which allows the site operator to efficiently move between the systems. 
         [0101]    The pipeline  100  would extend through the site and each of the biomass growing systems would feed into the pipeline  100  with a check valve (not shown) present between the pipeline  100  and the system  10 . Preferably, the pipeline  100  would be pressurized and once biomass/growth medium is output to it, the pressure gradient forces the biomass/growth medium mixture to a desired location. Alternatively, the pipeline  100  may be flushed with additional liquid growth medium or another liquid to transport the biomass/growth medium mixture to a desired location. 
         [0102]    Although the present invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention will become apparent to persons skilled in the art upon the reference to the above description of the invention. It is, therefore, contemplated that the appended claims will cover such modifications that fall within the scope of the invention.