Abstract:
A system and method for creating a useful carbon-enriched media in a reactor which will assimilate carbon into an algae biomass, requires measuring a respective carbon concentration of the media, C (measured) , as it enters, and as it leaves the reactor. Operationally, desired carbon concentration values are preset, C (set) , and are provided along with values obtained for C (measured)  as input to a system controller. Respective differentials between C (measured)  and C (set)  at the reactor&#39;s input and output ports are determined by the controller and are used to control a volumetric fluid flow rate of the media through the reactor. Specifically, the controller establishes a volumetric fluid flow rate of the media as it is passed through an absorber where the media is carbon-enriched by interaction with combustion gases from an external source (e.g. a power plant).

Description:
[0001]    This application is a continuation-in-part of application Ser. No. 12/817,043, filed Jun. 16, 2010, which is currently pending. The contents of application Ser. No. 12/817,043 are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention pertains generally to methods for growing algae. More particularly, the present invention pertains to the use of a medium for growing algae that is comprised of a solution containing carbon. The present invention is particularly, but not exclusively, useful as a system for supporting growth of algae with bicarbonate solution, and with charging used solution with adsorbed carbon dioxide at a liquid-gas contact medium for further support of algae growth. 
       BACKGROUND OF THE INVENTION 
       [0003]    As worldwide petroleum deposits decrease, there is rising concern over petroleum shortages and the costs that are associated with the production of hydrocarbon products. As a result, alternatives to products that are currently processed from petroleum are being investigated. In this effort, biofuel, such as biodiesel, has been identified as a possible alternative to petroleum-based transportation fuels. In general, a biodiesel is a fuel comprised of mono-alkyl esters of long chain fatty acids derived from plant oils or animal fats. In industrial practice, biodiesel is created when plant oils or animal fats react with an alcohol, such as methanol. 
         [0004]    For plant-derived biofuel, solar energy is first transformed into chemical energy through photosynthesis. The chemical energy is then refined into a usable fuel. Currently, the process involved in creating biofuel from plant oils is expensive relative to the process of extracting and refining petroleum. It is possible, however, that the cost of processing a plant-derived biofuel could be reduced by maximizing the rate of growth of the plant source. Because algae is known to be one of the most efficient plants for converting solar energy into cell growth, it is of particular interest as a biofuel source. Importantly, the use of algae as a biofuel source presents no exceptional problems, i.e., biofuel can be processed from oil in algae as easily as from oils in land-based plants. 
         [0005]    While algae can efficiently transform solar energy into chemical energy via a high rate of cell growth, it has been difficult to create environments in which algae cell growth rates are optimized. Specifically, the conditions necessary to facilitate a fast growth rate for algae cells in large-scale operations have been found to be expensive to create. While sunlight can be cheaply and easily fed to algae, the other sources of growth may require expensive distribution systems. For instance, it may be difficult to provide carbon dioxide at the appropriate levels throughout a system. For commercial purposes, reliance on normal absorption of CO 2  from the atmosphere, such as at a pond-air interface, is too slow. On the other hand, conventional pumping techniques with extensive piping networks are too costly. Thus, an alternate source of CO 2  is required. One possible source of carbon dioxide is found in flue gases from power plants or other combustion sources. Further, the carbon dioxide in flue gases is generally treated as pollution. Therefore, using carbon dioxide from flue gases will help abate pollution. 
         [0006]    A commercially viable source of CO 2  for algae photosynthesis is a bicarbonate solution. During this photosynthesis, it happens that a carbonate solution is generated. Further, it is known that such a carbonate solution will adsorb CO 2  from air (albeit somewhat inefficiently) for conversion back to a bicarbonate solution. Within this cycle, in a microalgae bioreactor system, the conversion from a bicarbonate solution to a carbonate solution is a consequence of algae growth. On the other hand, as mentioned above, the conversion from a carbonate solution (medium) to a bicarbonate solution can be accomplished merely by exposure to air. Also, in a situation where algae are being grown in a bioreactor system for the purpose of manufacturing a biodiesel fuel, CO 2  can be recovered from the power plant effluent to create a bicarbonate solution. 
         [0007]    In light of the above, it is an object of the present invention to provide a controlled system for supporting the growth of algae which also reduces fossil fuel pollution. Another object of the present invention is to provide a system for growing algae which reduces input costs. Another object of the present invention is to control the adsorption of carbon dioxide at a liquid-gas contact medium into a solution for feeding algae. Another object of the present invention is to provide a system for growing algae that utilizes a bicarbonate solution to deliver carbon to the algae. Another object of the present invention is to replenish spent medium with carbon dioxide in order to support further growth of algae in the medium. Still another object of the present invention is to introduce a bicarbonate solution into an algae growth medium to establish elevated CO 2  levels in a bioreactor system for algae growth. Another object of the present invention is to recycle a carbonate solution from a bioreactor system for conversion to a bicarbonate solution for subsequent use in growing algae in the bioreactor system. Yet another object of the present invention is to provide a system and method for growing algae that is simple to implement, easy to use, and comparatively cost effective. 
       SUMMARY OF THE INVENTION 
       [0008]    In accordance with the present invention, a system and method are provided for growing algae. Importantly, the system and method provide for the adsorption of carbon dioxide into the medium for supporting algae growth. Further, the system is able to use the carbon dioxide from flue gases or other pollution. 
         [0009]    In the system, a channel holds bicarbonate solution to support algae growth. During growth, the algae uses carbon dioxide and converts the bicarbonate solution into carbonate solution. In order to reuse the solution, the system provides a high surface area gas-liquid contact medium. Specifically, the carbonate solution is delivered to and moves through the gas-liquid contact medium. At the same time, air including the carbon dioxide is moved across the contact medium. During contact between the gas and liquid, the carbonate solution adsorbs carbon dioxide from the air and is converted into bicarbonate solution. After this process is completed, the bicarbonate solution is returned to the channel to support further algae growth. 
         [0010]    When used with a power plant, the system can be optimized by using steam power from the power plant for operation. Specifically, a fan using the steam power can direct the air across the contact medium. Further, the steam power can be used to move the solution to, from, and within the channel. 
         [0011]    An important aspect of the present invention is its incorporation of a controller (i.e. a computer) that monitors and controls the carbon enrichment of an algae growth media in a reactor. For purposes of the present invention this reactor may be either a pond, a plug flow reactor, an expanding plug flow reactor, or any other type reactor that is useful for growing an algae biomass. Regardless of type, however, the controller provides control over carbon concentration levels for the growth media in the reactor. To do this, the reactor in which an algae biomass is to be grown is configured with sensors that detect the carbon concentration in the growth media as it enters the reactor, and as it exits the reactor. Optimally, the carbon concentration of growth media entering the reactor will be sufficiently carbon-enriched to maximize growth of an algae biomass as it is being processed in the reactor. A necessary consequence of this, however, is that the carbon concentration of growth media exiting the reactor should not already be completely depleted of carbon. Nevertheless, it should be relatively carbon-poor. In either event, it needs to be enriched before it is used as the growth media in a subsequent cycle. 
         [0012]    As envisioned for the present invention, exhaust gases from a carbon-rich source, such as a power plant, are used to provide the carbon that is needed for enriching the post-cycle, carbon-poor algae growth media from the reactor before it is returned to the reactor as a carbon-enriched media. In this cycle, carbon concentration levels, both upstream and downstream from the reactor, are measured and respectively compared by the controller with preset carbon concentration levels that are identified for optimal system performance. Based on these comparisons, the volumetric flow rate of the media through an absorber, which provides carbon enrichment for the growth media, is controlled to achieve the optimal carbon concentrations. 
         [0013]    Structurally, the reactor that is used for growing algae biomass in the media has an input port and an output port. Also included in the system is an absorber which includes a plurality of panels. Further, the absorber has a first input port, a second input port, a first output port and a second output port. Another important component of the system is a source of combustion gases having a conduit for directing the combustion gases into the absorber through its first input port. 
         [0014]    Interconnecting components within the system include a pump for establishing a volumetric flow rate of carbon-poor media from the output port of the reactor and into the second input port of the absorber. As envisioned for the present invention, carbon-poor growth media from the reactor is presented on panel surface areas in the absorber for a counter current flow interaction with the combustion gases. It is this interaction that creates the carbon-enriched growth media for discharge from the first output port of the absorber. The carbon-enriched growth media is then introduced into the reactor through the input port of the reactor. Another structural component is a recycling pump for transferring media from the second output port of the absorber and back into the absorber via its second input port. 
         [0015]    Control for the system is accomplished by the controller which requires a first sensor for measuring a first carbon concentration level, C 1(measured) , in the reactor. Specifically, C 1(measured)  is taken downstream from the reactor at or near the output port of the reactor. Also included is a second sensor for measuring a second carbon concentration level, C 2(measured) , of media entering the reactor. This is the same media that is discharged from the first output port of the absorber. The controller then operates the pump with input from the first and second sensors to establish an optimized assimilation of captured carbon from the carbon-enriched growth media into the algae biomass in the reactor. 
         [0016]    In addition to taking carbon concentration measurements as disclosed above, a methodology for controlling the system of the present invention involves inputting the controller with a first preset carbon concentration C 1(set)  and a second preset carbon concentration C 2(set) . In detail the first preset carbon concentration C 1(set)  is based on an apparent carbon dioxide CO 2  concentration gradient which is determined by an interaction between aqueous media in the reactor and the atmosphere of the local environment of the reactor (e.g. bicarbonate, carbonic acid or carbon dioxide). Similarly, the second preset carbon concentration C 2(set)  is based on an apparent carbon dioxide CO 2  concentration gradient which is determined by an interaction between combustion gases and the relatively carbon-poor growth media that is introduced into the absorber. 
         [0017]    For an operation of the present invention, the pump is activated by the controller to operate with a predetermined high fluid flow rate when C 1(measured)  is below C 1(set) . Alternatively, the high fluid flow rate can be employed when C 2(measured)  is below C 2(set) . On the other hand, the pump can be activated to operate with a predetermined low fluid flow rate when C 1(measured)  is above C 1(set) . 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which: 
           [0019]      FIG. 1  is a schematic view of an algae growing system in accordance with the present invention; 
           [0020]      FIG. 2  is a schematic view of the conversion between carbonate and bicarbonate for the present invention; 
           [0021]      FIG. 3  is a schematic presentation of operative components for controlling the carbon enrichment of a media for growing an algae biomass in a reactor; 
           [0022]      FIG. 4  is a perspective schematic view of components for an exemplary absorber as envisioned for the present invention; and 
           [0023]      FIG. 5  is a decision flow chart for the operation of a system in accordance with the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    Referring to  FIG. 1 , a system for producing biofuel from pollutant-fed algae is shown and generally designated  10 . As shown, the system  10  includes a scrubber  12  for scrubbing a pollutant-contaminated fluid stream. Specifically, the scrubber  12  includes a chamber  14  and an input port  16   a  for receiving flue gas from a combustion source such as a power plant  18  and a scrubber solution  20 . Typically, the flue gas includes pollutants such as carbon dioxide, sulfur oxides, and/or nitrogen oxides. Also, the scrubber solution  20  typically comprises sodium bicarbonate. As further shown, the scrubber  12  includes a solution outlet  22  and a gas outlet  24 . Also, the system  10  includes an oxidation stage  26  for oxidizing pollutants in the flue gas to facilitate their removal from the flue gas. As shown, the oxidation stage  26  is interconnected between the power plant  18  and the scrubber  12 . 
         [0025]    As further shown, the system  10  includes a bioreactor  28  comprised of at least one chemostat  30  for growing algae cells (exemplary cells depicted at  32 ) and a plug flow reactor  34  for treating the algae cells  32  to trigger cell production of triglycerides. Preferably, and as shown, both the chemostat  30  and the plug flow reactor  34  are open raceways, though closed systems are also contemplated. Further, such open systems  10  can cover several acres of land to optimize economies of scale. For purposes of the present invention, the system  10  includes an algae separator  36  for removing the algae cells  32  from the plug flow reactor  34 . As shown in  FIG. 1 , the chemostat  30  includes a channel  38 . As further shown, the channel  38  is provided with an input port  40  that is in fluid communication with the solution outlet  22  of the scrubber chamber  14 . For purposes of the present invention, the input port  40  is also in communication with a reservoir (not illustrated) holding a nutrient mix (indicated by arrow  42 ). Preferably, the nutrient mix  42  includes phosphorous, nitrogen, sulfur and numerous trace elements necessary to support algae growth that are not provided to the bioreactor  28  by the scrubber solution  20 . Further, the chemostat  30  is provided with a paddlewheel  44  for causing the medium  46  formed by the scrubber solution  20  and the nutrient mix  42  to continuously circulate around the channel  38  at a predetermined fluid flow velocity. Also, each channel  38  is provided with an output port  48  in communication with the plug flow reactor  34 . 
         [0026]    As shown, the plug flow reactor  34  includes an input port  50   a  for receiving overflow medium (indicated by arrow  46 ′) with algae cells  32  from the output port  48  of the chemostat  30 . As further shown, the plug flow reactor  34  includes a channel  52  for passing the medium  46 ″ with algae cells  32  downstream. The flow rate of the medium  46 ″ is due solely to gravity and the force of the incoming overflow medium  46 ′ from the chemostat  30 . Preferably, the plug flow reactor  34  has a substantially fixed residence time of about one to four days. For purposes of the present invention, the system  10  is provided with a reservoir (not shown) that holds a modified nutrient mix (indicated by arrow  54 ). Further, the channel  52  is provided with an input port  50   b  for receiving the modified nutrient mix  54 . In order to manipulate the cellular behavior of algae cells  32  within the plug flow reactor  34 , the modified nutrient mix  54  may contain a limited amount of a selected constituent, such as nitrogen or phosphorous. For instance, the nutrient mix  54  may contain no nitrogen. Alternatively, the algae cells  32  may exhaust nutrients such as nitrogen or phosphorous in the nutrient mix  42  at a predetermined point in the plug flow reactor  34 . By allowing such nutrients to be exhausted, desired behavior in the algae cells  32  can be caused without adding a specific modified nutrient mix  54 . Further, simply water can be added through the modified nutrient mix  54  to compensate for evaporation. In addition to input ports  50   a  and  50   b , the channel  52  is further provided with an input port  50   c  to receive other matter. 
         [0027]    In  FIG. 1 , the algae separator  36  is shown in fluid communication with the channel  52  of the plug flow reactor  34 . For purposes of the present invention, the algae separator  36  separates the algae cells  32  from the medium  46 ″ and the remaining nutrients therein through flocculation and/or filtration. As further shown, the algae separator  36  includes an effluence outlet  56  and an algae cell outlet  60 . For purposes of the present invention, the system  10  includes a channel  58  providing fluid communication between the effluence outlet  56  and the scrubber  12  through a solution input port  16   b  in the scrubber chamber  14 . 
         [0028]    Also, the system  10  includes a cell lysis apparatus  62  that receives algae cells  32  from the algae outlet  60  of the algae separator  36 . As shown, the cell lysis apparatus  62  is in fluid communication with an oil separator  64 . For purposes of the present invention, the oil separator  64  is provided with two outlets  66 ,  68 . As shown, the outlet  66  is connected to a hydrolysis apparatus  70 . Further, the hydrolysis apparatus  70  is connected to the input port  40  in the channel  38  of the chemostat  30 . 
         [0029]    Referring back to the oil separator  64 , it can be seen that the outlet  68  is connected to a biofuel reactor  72 . It is further shown that the biofuel reactor  72  includes two exits  74 ,  76 . For purposes of the present invention, the exit  74  is connected to the input port  50   c  in the channel  52  of the plug flow reactor  34 . Additionally or alternatively, the exit  74  may be connected to the input port  40  in the chemostat  30 . Further, the exit  76  may be connected to a tank or reservoir (not shown) for purposes of the present invention. 
         [0030]    In operation of the present invention, pollutant-contaminated flue gas (indicated by arrow  78 ) is directed from the power plant  18  to the oxidation stage  26 . At the oxidation stage  26 , nitrogen monoxide in the flue gas  78  is oxidized by nitric acid or by other catalytic or non-catalytic technologies to improve the efficiency of its subsequent removal. Specifically, nitrogen monoxide is oxidized to nitrogen dioxide. Thereafter, the oxidized flue gas (indicated by arrow  80 ) is delivered from the oxidation stage  26  to the scrubber  12 . Specifically, the oxidized flue gas  80  enters the chamber  14  of the scrubber  12  through the input port  16   a . Upon the entrance of the flue gas  80  into the chamber  14 , the scrubber solution  20  is sprayed within the chamber  14  to absorb, adsorb or otherwise trap the pollutants in the flue gas  80  as is known in the field of scrubbing. With its pollutants removed, the clean flue gas (indicated by arrow  82 ) exits the scrubber  12  through the gas outlet  24 . At the same time, the scrubber solution  20  and the pollutants exit the scrubber  12  through the solution outlet  22 . 
         [0031]    After exiting the scrubber  12 , the scrubber solution  20  and pollutants (indicated by arrow  84 ) enter the chemostat  30  through the input port  40 . Further, the nutrient mix  42  is fed to the chemostat  30  through the input port  40 . In the channel  38  of the chemostat  30 , the nutrient mix  42 , scrubber solution  20  and pollutants (arrow  84 ) form the medium  46  for growing the algae cells  32 . This medium  46  is circulated around the channel  38  by the paddlewheel  44 . Further, the conditions in the channel  38  are maintained for maximum algal growth. For instance, in order to maintain the desired conditions, the medium  46  and the algae cells  32  are moved around the channel  38  at a preferred fluid flow velocity of approximately fifty centimeters per second. Further, the amount of algae cells  32  in the channel  38  is kept substantially constant. Specifically, the nutrient mix  42  and the scrubber solution  20  with pollutants (arrow  84 ) are continuously fed at selected rates into the channel  38  through the input port  40 , and an overflow medium  46 ′ containing algae cells  32  is continuously removed through the output port  48  of the channel  38 . 
         [0032]    After entering the input port  50   a  of the plug flow reactor  34 , the medium  46 ″ containing algae cells  32  moves downstream through the channel  52  in a plug flow regime. Further, as the medium  46 ″ moves downstream, the modified nutrient mix  54  may be added to the channel  52  through the input port  50   b . This modified nutrient mix  54  may contain a limited amount of a selected constituent, such as nitrogen or phosphorous. The absence or small amount of the selected constituent causes the algae cells  32  to focus on energy storage rather than growth. As a result, the algae cells  32  form triglycerides. 
         [0033]    At the end of the channel  52 , the algae separator  36  removes the algae cells  32  from the remaining effluence (indicated by arrow  86 ). Thereafter, the effluence  86  is discharged from the algae separator  36  through the effluence outlet  56 . In order to recycle the effluence  86 , it is delivered through channel  58  to the input port  16   b  of the scrubber  12  for reuse as the scrubber solution  20 . Further, the removed algae cells (indicated by arrow  88 ) are delivered to the cell lysis apparatus  62 . Specifically, the removed algae cells  88  pass out of the algae cell outlet  60  to the cell lysis apparatus  62 . For purposes of the present invention, the cell lysis apparatus  62  lyses the removed algae cells  88  to unbind the oil therein from the remaining cell matter. After the lysing process occurs, the unbound oil and remaining cell matter, collectively identified by arrow  90 , are transmitted to the oil separator  64 . Thereafter, the oil separator  64  withdraws the oil from the remaining cell matter as is known in the art. After this separation is performed, the oil separator  64  discharges the remaining cell matter (identified by arrow  92 ) out of the outlet  66  of the oil separator  64  to the input port  40  of the chemostat  30 . 
         [0034]    In the chemostat  30 , the remaining cell matter  92  is utilized as a source of nutrients and energy for the growth of algae cells  32 . Because small units of the remaining cell matter  92  are more easily absorbed or otherwise processed by the growing algae cells  32 , the remaining cell matter  92  may first be broken down before being fed into the input port  40  of the chemostat  30 . To this end, the hydrolysis apparatus  70  is interconnected between the oil separator  64  and the chemostat  30 . Accordingly, the hydrolysis apparatus  70  receives the remaining cell matter  92  from the oil separator  64 , hydrolyzes the received cell matter  92 , and then passes hydrolyzed cell matter (identified by arrow  94 ) to the chemostat  30 . 
         [0035]    Referring back to the oil separator  64 , it is recalled that the remaining cell matter  92  was discharged through the outlet  66 . At the same time, the oil withdrawn by the oil separator  64  is discharged through the outlet  68 . Specifically, the oil (identified by arrow  96 ) is delivered to the biofuel reactor  72 . In the biofuel reactor  72 , the oil  96  is reacted with alcohol, such as methanol, to create mono-alkyl esters, i.e., biofuel fuel. This biofuel fuel (identified by arrow  98 ) is released from the exit  76  of the biofuel reactor  72  to a tank, reservoir, or pipeline (not shown) for use as fuel. In addition to the biofuel fuel  98 , the reaction between the oil  96  and the alcohol produces glycerin as a byproduct. For purposes of the present invention, the glycerin (identified by arrow  100 ) is pumped out of the exit  74  of the biofuel reactor  72  to the input port  50   c  of the plug flow reactor  34 . 
         [0036]    In the plug flow reactor  34 , the glycerin  100  is utilized as a source of carbon by the algae cells  32 . Importantly, the glycerin  100  does not provide any nutrients that may be limited to induce oil production by the algae cells  32  or to trigger flocculation. The glycerin  100  may be added to the plug flow reactor  34  at night to aid in night-time oil production. Further, because glycerin  100  would otherwise provide bacteria and/or other non-photosynthetic organisms with an energy source, limiting the addition of glycerin  100  to the plug flow reactor  34  only at night allows the algae cells  32  to utilize the glycerin  100  without facilitating the growth of foreign organisms. As shown in  FIG. 1 , the exit  74  of the biofuel reactor  72  may also be in fluid communication with the input port  40  of the chemostat  30  (connection shown in phantom). This arrangement allows the glycerin  100  to be provided to the chemostat  30  as a carbon source. While  FIG. 1  illustrates that a paddlewheel  44  or gravity for moving the medium  46  through the channels  38  and  52 , steam power  102  from the power plant  18  may be used to power such movement. 
         [0037]    In  FIG. 2 , a system for supporting algae growth with adsorbed carbon dioxide is illustrated and generally designated  103 . In  FIG. 2 , the channels  38  and  52  are represented collectively by reference number  104 . These channels  104  hold the medium  46  that includes bicarbonate solution. As algae  32  grows in the channels  104  it depletes the medium  46  of carbon and the medium  46  becomes principally carbonate solution. In order to replenish the carbonate solution, the system  103  provides for removal of the carbonate solution  106  from the channels  104 . As shown, the carbonate solution  106  is delivered to a high surface area liquid-gas contact medium  108 . As shown, a fan  110 , powered by steam power  102 , moves air  112  including carbon dioxide across the contact medium  108 . As a result, when the carbonate solution  106  moves slowly across or drips through the contact medium  108 , it adsorbs carbon dioxide and is converted back into bicarbonate solution. Thereafter, the bicarbonate solution  114  is returned from the contact medium  108  to the channels  104  to support further growth of the algae  32  therein. 
         [0038]    Referring now to  FIG. 3 , a system for controlling the carbon enrichment of a media for growing an algae biomass in accordance with the present invention is shown and is generally designated  120 . As shown, the system  120  includes a reactor  122  that may be of any type well known in the pertinent art, such as a standard plug flow reactor, an expanding plug flow reactor, or a pond. The system  120  also includes an absorber  124  and a power plant  126 . In this combination, the reactor  122  and the absorber  124  are connected in fluid communication with each other. The power plant  126  is also connected in fluid communication with the absorber  124 . As envisioned for the present invention, the power plant  126  is incorporated as a source of the combustion gases that are to be directed into the absorber  124 . Further, the system  120  requires a controller  128  which will effectively control the flow of the media through the reactor  122  and through the absorber  124  for carbon enrichment of the media. 
         [0039]    Still referring to  FIG. 3 , it will be seen that the reactor  122  has an input port  130  and an output port  132 . Also, seen in  FIG. 3  is that the absorber  124  has a media input port  134 , a gas input port  136 , a media output port  138  and a recycle output port  140 . Interconnecting components in the system  120  include a sensor  142  that is positioned between the output port  132  of the reactor  122  and a pump  144 . Specifically, the pump  144  is incorporated into the system  120  for the purpose of pumping media from the reactor  122  to the media input port  134  of the absorber  124  via a media flow line  146 . In detail, the sensor  142  is positioned on the media flow line  146  for the purpose of measuring the carbon concentration level of media passing from the reactor  122  through the media flow line  146 . For clarity the media flow line  146  is shown in  FIG. 3  as a double line. Like sensor  142 , a sensor  148  is shown positioned between the media output port  138  of the absorber  124  and the input port  130  of the reactor  122 . Further, a recycle pump  150  can be included in the system  120  to establish a recycle flow line  152  between the recycle output port  140  of the absorber  124  and the media flow line  146  for fluid transfer back into the absorber  124  via the media input port  134  of the absorber  124 . 
         [0040]    As intended for the present invention, the carbon enrichment of the growth media is accomplished in the absorber  124 . Referring now to  FIG. 4 , it will be seen that the absorber  124  includes a plurality of panels  154 , with each panel  154  having an exposed surface  156 . As shown, the media flow line  146  directs media into the absorber  124  through the media input port  134 . Also, combustion gases  158  are directed from the power plant  126  into the absorber  124  through the gas input port  136 . Thus, as media passes through the absorber  124  it is presented on the respective surfaces  156  of the plurality of panels  154 . The resultant dispersion of media on the surfaces  156  then facilitates the capture of carbon by the media from the combustion gases  158  during a counter flow of the combustion gases  158  over the media on the surfaces  156  of respective panels  154 . The result here is that when a carbon-poor media is introduced into the absorber  124  through the media input port  134 , a carbon-enriched media will be returned to the reactor  122  via the media output port  138 . 
         [0041]      FIG. 5  presents a decision flow chart  160  in which action blocks  162  and  164  indicate that certain parameters and measurements are required by the controller  128  for an operation of the system  120 . Specifically,  FIG. 3  indicates that the sensor  142  monitors and measures the media flow line  146  to obtain a first carbon concentration level, C 1(measured) , of the media as it exits from the reactor  122  through output port  132 .  FIG. 3  also indicates that the sensor  148  monitors and measures a second carbon concentration level, C 2(measured) , of the media as it is discharged from the media output port  138  of the absorber  124  for introduction into the reactor  122  through the input port  130 . Additionally, action block  162  of the decision flow chart  160  requires input for the controller  128  in the form of a first preset carbon concentration C 1(set) , and a second preset carbon concentration C 2(set) . In detail, the first preset carbon concentration C 1(set)  is based on an apparent carbon dioxide CO 2  concentration gradient that is determined by an interaction between aqueous media in the reactor  122  and the atmosphere of the local environment of the reactor  122 . As envisioned for the present invention this local environment may include bicarbonate, carbonic acid or carbon dioxide. On the other hand, the second preset carbon concentration C 2(set)  is based on an apparent carbon dioxide CO 2  concentration gradient determined by an interaction between the combustion gases  158  from the power plant  126  and relatively carbon-poor growth media in the absorber  124 . As stated above, both C 1(set)  and C 2(set)  are predetermined inputs to the controller  128 . 
         [0042]    Inquiry block  166  in  FIG. 5  indicates that the pump  144  is to be activated to operate with a predetermined low fluid flow rate (see action block  168 ), when C 1(measured)  from sensor  142  is above (i.e. not below) C 1(set) . On the other hand, inquiry block  166  indicates that the pump  144  is to be activated to operate with a predetermined high fluid flow rate (see action block  170 ) when C 1(measured)  is below C 1(set) . In either case, inquiry block  172  indicates that the recycle pump  150  may be activated to recycle media (see block  174 ) whenever C 2(measured)  is below C 2(set) . The intended consequence of all this is that the system  120  is operated with an optimal transfer of carbon from the media for the production of a biomass  176  (see  FIG. 3 ). 
         [0043]    While the particular Controlled System for Supporting Algae Growth with Adsorbed Carbon Dioxide as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.