Sustainable photobioreactor

Abstract

Photobioreactors are described herein. The photobioreactors include a vessel for cultivating microalgae. The vessel defines an interior chamber comprising a culture containing medium. The vessel has at least one transparent wall to permit passage of light of a frequency necessary to promote growth of the microalgae in the culture containing medium. The vessel also includes a plurality of sensors, each sensor being configured to monitor at least one environmental condition within the photobioreactor, and at least one flow generator positioned within the vessel. The photobioreactor also includes a controller communicatively coupled to each of the plurality of sensors and the at least one flow generator. The controller is configured to: receive sensor data from each of the plurality of sensors, apply a mathematical model to the sensor data to determine when to adjust at least one environmental condition within the photobioreactor and adjust one or more components of the photobioreactor.

Description

SUSTAINABLE PHOTOBIOREACTORFIELD

[0001] This disclosure relates generally to photobioreactors and, more specifically to sustainable photobioreactors.BACKGROUND

[0002] Microalgae are a potential solution to the increasing need to reduce carbon dioxide levels in the atmosphere. The use of microalgae comes with many advantages. First, microalgae exhibit productivity characteristics far superior to plants in general. The fastest-growing microalgae divide and double in number every 3 hours. In addition to carbon dioxide, microalgae can remove other pollutants from fluids, such as but not limited to ammonia, nitrates, and phosphates. Also, cultured microalgae can produce useful natural substances, such as oxygen and antioxidants. After extracting such substances, the byproducts can be used as a fuel source for a wide variety of purposes.

[0003] However, there are various technical hurdles to be overcome for the mass culturing of microalgae. Processes for the culture of microalgae account for more than 50% of total costs, followed by harvesting, concentration, drying, and separation and extraction.

[0004] Accordingly, there is a need for a new sustainable photobioreactors.SUMMARY

[0005] In accordance with a broad aspect, a photobioreactor for producing and harvesting microalgae is described herein. The photobioreactor includes a vessel for cultivating microalgae. The vessel defines an interior chamber comprising a culture containing medium. The vessel has at least one wall being transparent to permit passage of light of a frequency necessary to promote growth of the microalgae in the culture containing medium. The vessel also includes a plurality of sensors, each sensor being configured to monitor at least one environmental condition within the photobioreactor. Thevessel also includes at least one flow generator positioned within the vessel, each flow generator being configured to direct a flow of the culture containing medium within the vessel. The vessel also includes a controller communicatively coupled to each of the plurality of sensors and the at least one flow generator, the controller being configured to: receive sensor data from each of the plurality of sensors, the sensor data including data of at least one environmental parameter within the photobioreactor; apply a mathematical model to the sensor data to determine when to adjust at least one component of the photobioreactor to optimize the at least one environmental condition monitored within the photobioreactor; and in response to determining to adjust the at least one component, adjust the at least one component by at least one of opening, closing, turning on, turning off, adjusting a flow rate into, adjusting a flow rate out of, and adjusting a mixing rate within the photobioreactor and / or adjusting a light intensity of light emitters of the photobioreactor.

[0006] In at least one embodiment, the at least one environmental condition includes at least one of a conversion rate, flow rate, temperature, nutrient concentration, pH level, dissolved gas concentration, light intensity within the photobioreactor.

[0007] In at least one embodiment, the nutrient concentration includes nitrogen concentration and phosphorus concentration.

[0008] In at least one embodiment, the dissolved gas concentration includes carbon dioxide concentration and oxygen concentration.

[0009] In at least one embodiment, the controller implements at least one of artificial intelligence, machine learning, and deep learning to optimize predictive analytics for quality control monitoring.

[0010] In at least one embodiment, the vessel is a base of a patio umbrella.

[0011] In at least one embodiment, the vessel is a post and / or a base of a patio umbrella.

[0012] In at least one embodiment, the photobioreactor also includes a dewatering unit configured to receive biomass from the vessel, the dewatering unit configured toremove water from the biomass received from the vessel and produce a dewatered biomass stream.

[0013] In at least one embodiment, the photobioreactor also includes a conversion unit configured to receive the dewatered biomass stream and convert the dewatered biomass stream into a nutrient rich-stream for providing to the vessel, conversion unit being configured to perform at least one of pyrolysis, anerobic digestion and fermentation to produce the nutrient-rich stream.

[0014] In at least one embodiment, the photobioreactor also includes a nutrient-rich stream inlet configured to control a volume and / or flow rate of the nutrient rich-stream into the vessel, the controller being communicatively coupled to the nutrient-rich stream inlet and configured to open and close the nutrient-rich stream inlet based on an optical density of the culture containing medium in the vessel.

[0015] In at least one embodiment, the nutrient-rich stream enters the vessel above a surface of the culture containing medium.

[0016] In at least one embodiment, the nutrient-rich stream enters the vessel below a surface of the culture containing medium.

[0017] In at least one embodiment, the photobioreactor also includes a heat exchanger communicatively coupled to the controller, the controller being configured to control a temperature of the culture containing medium with the heat exchanger.

[0018] In at least one embodiment, the environmental condition is conversion of carbon dioxide into oxygen and the controller is configured to optimize conversion of carbon dioxide into oxygen within the vessel by adjust the at least one component of the photobioreactor, and the adjusting include adjusting a flow rate of the nutrient-rich stream into the vessel.

[0019] In accordance with another broad aspect, a method of providing a photobioreactor housing microalgae is described herein. The method includes providing air to a vessel of the photobioreactor, the air including carbon dioxide and oxygen; monitoring one or more parameters of the photobioreactor during photosyntheticconversion of the carbon dioxide to oxygen, the photosynthetic conversion being encouraged by the microalgae, the one or more parameters including an optical density of a cell culture medium including the microalgae; based on at least the optical density of the cell culture medium including the microalgae, controlling a volume of a biomass stream exiting the vessel of the photobioreactor; converting the biomass stream into a nutrient rich stream; and returning at least a portion of the nutrient rich stream to the photobioreactor.

[0020] These and other features and advantages of the present application will become apparent from the following detailed description taken together with the accompanying drawings. It should be understood, however, that the detailed description and the specific examples, while indicating preferred embodiments of the application, are given by way of illustration only, since various changes and modifications within the spirit and scope of the application will become apparent to those skilled in the art from this detailed description.BRIEF DESCRIPTION OF THE DRAWINGS

[0021] For a better understanding of the various embodiments described herein, and to show more clearly how these various embodiments may be carried into effect, reference will be made, by way of example, to the accompanying drawings which show at least one example embodiment, and which are now described. The drawings are not intended to limit the scope of the teachings described herein.

[0022] FIG. 1 is a diagram of a photobioreactor according to at least one embodiment described herein.

[0023] FIG. 2 is a picture of a photobioreactor according to at least one embodiment described herein.

[0024] FIG. 3 is a diagram of a computer system of a photobioreactor according to at least one embodiment described herein.

[0025] FIG. 4 is a flow chart of a method of operating a photobioreactor according to at least one embodiment described herein.

[0026] Further aspects and features of the example embodiments described herein will appear from the following description taken together with the accompanying drawings.DESCRIPTION OF EXAMPLE EMBODIMENTS

[0027] Various apparatuses, methods and compositions are described below to provide an example of at least one embodiment of the claimed subject matter. No embodiment described below limits any claimed subject matter and any claimed subject matter may cover apparatuses and methods that differ from those described below. The claimed subject matter are not limited to apparatuses, methods and compositions having all of the features of any one apparatus, method or composition described below or to features common to multiple or all of the apparatuses, methods or compositions described below. It is possible that an apparatus, method or composition described below is not an embodiment of any claimed subject matter. Any subject matter that is disclosed in an apparatus, method or composition described herein that is not claimed in this document may be the subject matter of another protective instrument, for example, a continuing patent application, and the applicant(s), inventor(s) and / or owner(s) do not intend to abandon, disclaim, or dedicate to the public any such invention by its disclosure in this document.

[0028] Furthermore, it will be appreciated that for simplicity and clarity of illustration, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the example embodiments described herein. However, it will be understood by those of ordinary skill in the art that the example embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the example embodiments described herein. Also, the description is not to be considered as limiting the scope of the example embodiments described herein.

[0029] It should be noted that terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modifiedterm such that the end result is not significantly changed. These terms of degree should be construed as including a deviation of the modified term, such as 1 %, 2%, 5%, or 10%, for example, if this deviation does not negate the meaning of the term it modifies.

[0030] Furthermore, the recitation of any numerical ranges by endpoints herein includes all numbers and fractions subsumed within that range (e.g., 1 to 5 includes 1 , 1.5, 2, 2.75, 3, 3.90, 4, and 5). It is also to be understood that all numbers and fractions thereof are presumed to be modified by the term “about” which means a variation up to a certain amount of the number to which reference is being made, such as 1 %, 2%, 5%, or 10%, for example, if the end result is not significantly changed.

[0031] It should also be noted that, as used herein, the wording “and / or” is intended to represent an inclusive - or. That is, “X and / or Y” is intended to mean X, Y or X and Y, for example. As a further example, “X, Y, and / or Z” is intended to mean X or Y or Z or any combination thereof. Also, the expression of A, B and C means various combinations including A; B; C; A and B; A and C; B and C; or A, B and C.

[0032] The following description is not intended to limit or define any claimed or as yet unclaimed subject matter. Subject matter that may be claimed may reside in any combination or sub-combination of the elements or process steps disclosed in any part of this document including its claims and figures. Accordingly, it will be appreciated by a person skilled in the art that an apparatus, system or method disclosed in accordance with the teachings herein may embody any one or more of the features contained herein and that the features may be used in any particular combination or sub-combination that is physically feasible and realizable for its intended purpose.

[0033] Recently, there has been a growing interest in developing new sustainable photobioreactors.

[0034] The systems, devices and methods described herein relate to a photobioreactor for the cultivation of photosynthetic microorganisms, as well as to related methods and uses of said systems for converting atmospheric carbon dioxide (CO2) into an oxygen-rich stream by cultivating photosynthetic microorganisms.

[0035] The systems, devices and methods described herein are designed to remove CO2 from atmospheric air, for example in an indoor or an outdoor environment, and generate oxygen (O2). The photobioreactors described herein use microalgae, described in greater detail below, grown in a liquid medium to remove CO2 from atmospheric air and generate O2.

[0036] The photobioreactors described herein are closed system designs where the parameters of photobioreactor when the microalgae are in their growth stage can be monitored and controlled to optimize conversion of CO2 from the environment to O2. Water and / or nutrients may be fed into the vessel, which may optionally be under positive pressure so no ingress from the surrounding environment occurs, thereby providing and maintaining a sterile environment by keeping any airborne organisms from contaminating the culture. The photobioreactors described herein provide for air to vent from the system, as O2 produced by the microalgae must escape to fresh the air or supply for medical care, aerospace and etc..

[0037] As the microalgae grow within the photobioreactor system, dead biomass accumulates within the system (through filtration). It should be understood that herein, the term “microalgae” is used to describe the living microorganisms contributing to the consumption of CC and the term “biomass” is used to refer to the matter from the recently living but now dead microalgae.

[0038] The photobioreactors described herein also include a mechanism for recycling biomass from the photobioreactor. The recycling process includes removing the biomass from the vessel of the photobioreactor where the microalgae are in their growth stage, dewatering the biomass, converting the biomass removed from the vessel housing the microalgae in their growth stage to nutrients that increase growth of the microalgae and returning the nutrients to the vessel housing the microalgae in their growth stage. Biomass accumulation in the photobioreactor can consume O2 and, therefore reduce net O2 generation from the photobioreactor.

[0039] The photobioreactor systems, methods, and devices described herein more effectively and efficiently cultivate convert CO2 to O2 by configuring a photobioreactor tooptimally stimulate biomass production and / or yield. The optimization may be enhanced by a unique arrangement of flow generators and / or light sources within the photobioreactor. The optimization may be enhanced by monitoring environmental conditions, optionally within the photobioreactor itself and / or outside of the photobioreactor, using sensors to provide sensor data to the controller that uses artificial intelligence (Al) and / or machine learning (ML) to process the sensor data while dynamically adjusting operations of various photobioreactor components to adjust one or more environmental conditions within the photobioreactor and, thereby, optimize biomass quality and / or yield to optimize conversion of CO2 to O2. There is an increased need for technologies that convert CO2 to O2, especially in a climate challenged world. The efficiencies and associated technologies described herein are needed to address the needs of an increased population. A new type of photobioreactor is proposed to address these unique challenges.

[0040] In a particular embodiment, shown generically in FIG. 1 , a photobioreactor 100 includes a vessel 110 having at least one transparent wall 112. Vessel 110 may be any liquid-holding vessel that, for example, may be one of various different types of photobioreactors and may have one of various different shapes. For example, photobioreactor 100 may be one of a tubular photobioreactor, a Christmas tree photobioreactor, a plate photobioreactor, a horizonal photobioreactor or the like. Additionally, photobioreactor 100 may be shaped as a cube, pyramid, cylinder, or the like. For example, without limiting the foregoing, vessel 110 may be a portion of a patio umbrella, such as a base, a pole and / or a shade of a patio umbrella. One example of a photobioreactor 200 shaped as a patio umbrella is shown in FIG. 2.

[0041] Vessel 110 is generally made of a suitable material that inhibits fouling of microalgae and / or biomass on an interior surface thereof. Reduction of fouling may reduce a need to clean the vessel 110 when microalgae circulate within the vessel 110 for extended periods of time (e.g., one or more months). In one embodiment, the vessel 110 may be shaped without any comers to inhibit fouling of algae and / or biomass on an interior surface thereof. The material for forming vessel 110 may be durable, low friction (e.g., smooth), not sensitive to high light (i.e. , in a range of about 500pmolrrr2s-1to about1000 pmol.m2s1photons), not sensitive to very low temperature (i.e., <15 °C), transparent, UV stable, water resistant (i.e., water will not evaporate from the vessel), and non-reactive.

[0042] Further, as noted above vessel 110 has at least one transparent wall 112. The transparent wall 112 may be made of a same material as noted above, or may be made of a different material. In either case, transparent wall 112 is sufficiently transparent to provide for passage of light from the environment around photobioreactor 100 into vessel 110 where the light can contribute to microalgal growth therein. For example, vessel 110, either entirely or only a portion that is transparent, may be made of ultra-high molecular weight (IIHMW) polyethylene or polypropylene (e.g., polypropylene that has been processed to be transparent).

[0043] Vessel 110 may also be manufactured of a material and in such a manner that an internal side of vessel 110 is smooth and there are no corners, edges, or rough surfaces that increase friction and are prone to adherence of biomass or contaminating components, which are commonly very difficult to clean and sterilize. By having a rounded and smooth construction, contamination within vessel 100 may be limited.

[0044] In at least one embodiment, vessel 110 may be insulated from outside environmental conditions such as, but not limited to, excess heat, excess cold, excess light, excess wind (e.g., have an aerodynamic shape), or a combination thereof. For example, vessel 110 may be insulated from temperature changes in the outside environment by including a transparent jacket or a transparent double jacket around a bubble column of vessel 110. For example, vessel 110 may include one or more materials to restrict portions of light (e.g., selected wavelengths) from entering the vessel 110 and / or may include automated light controls to control an amount of light that the cell media is exposed to within the vessel 110.

[0045] Vessel 110 is configured to receive atmospheric air including CO2. For example, vessel 110 may include an air inlet 114. Air inlet 114 may optionally include a one-way valve that inhibits flow of liquid (e.g., culture medium) outwardly from vessel 110 while providing for air to flow into vessel 110. Air inlet 114 may be positioned below asurface of cell culture medium within vessel 110. In FIG. 1 , the surface of the medium is indicated with reference no. 116. Inlet 114 may include a filter for removing dry particles from the air before the air enters vessel 110. Examples of airborne contaminants that may be removed prior to air entering vessel 110 be configured to remove may include mold spores, dust, bacteria, or volatile organic chemicals.

[0046] Photobioreactor 100 converts CO2-rich air into 02-rich by drawing atmospheric air (e.g., indoor air or outdoor air) through air inlet 114 into a portion (e.g., side, top or bottom) of vessel 110. Photobioreactor 100 includes a pump 118 configured to draw the atmospheric air from the environment around photobioreactor 100 into vessel 110 though inlet 114. Pump 118 can be any conventional pump known to one skilled in the art for drawing air from the environment into vessel 110.

[0047] Air entering vessel 114 flows through the cell culture medium contained in vessel 110. The cell culture medium includes microalgae that promote photosynthesis within the vessel 110 according to the following reaction:6 CO2 + 6 H2O -> C6H12O6 + 6 O2

[0048] After conversion of CO2 into O2 by the microalgae, oxygen-rich air passes upwardly within the vessel 110 towards air outlet 122 that provides for the oxygen-rich air to exit vessel 110 and enter the atmosphere. Air outlet 122 is positioned above the surface of the medium 116.

[0049] Vessel 110 also includes a heat exchanger 126. Heat exchanger 126 is configured to heat and / or cool the cell culture medium within the vessel 110 to increase and / or decrease a temperature of the cell culture medium. Heat exchanger 126 may be any conventional heater for increasing a temperature of the cell culture medium.

[0050] Photobioreactor 100 also includes an agitator 128 for circulating the cell culture medium within the vessel 110. Agitator 128 may be a mechanical agitator such as a stirrer or other similar rotating device. In another embodiment, agitator 128 may be a bubbling agitator that is connected to inlet 114. In this example, agitator 128 have receive air directly from the environment around the photobioreactor 100 via inlet 114 and inject itdirectly into the cell culture medium. Accordingly, agitator 128 is generally positioned within the vessel below the surface of the cell culture medium. Agitator 128 may include aeration at a centre of the vessel 110 or at a tangent to a reactor wall of vessel 110.

[0051] Vessel 110 may also include one or more light sources 140. Light source(s) 140 may include one or more (sunlight or artificial light) light emitting diode (LED) lights configured to provide a selected intensity and / or wavelength of light to the cell culture media. Photobioreactor 100 utilizes the light produced by light source 140 for the microalgae to consume light source during photosynthesis. Light source 140 may be positioned within vessel 110 or outside of vessel 110 in a position where light generated by the light source 140 is receivable by the cell culture media within the vessel 110.

[0052] Vessel 110 also includes one or more additional inlet and outlet ports to provide nutrients and / or water to facilitate the sustainable growth of the microalgae in the cell culture media and the continuous conversion of CO2 to O2. For example, vessel 110 includes a first inlet port 142 configured to receive additional water, second inlet port 144 configured to receive supplementary nutrients (e.g., capsules thereof) and third inlet 146 configured to receive decomposed biomass (described in greater detail below). Each of inlets 142, 144 and 146 may contain valves that are controllable to control the addition of additional water, supplementary nutrients and decomposed biomass, respectively. Supplemental water and / or supplementary nutrients and / or decomposed biomass may also be added directly to conversion unit 160.

[0053] As noted above, photobioreactor 100 is configured to recycle for recycling biomass from the photobioreactor. Biomass accumulation in the photobioreactor can consume O2 and, therefore reduce net O2 generation from the photobioreactor. The recycling process includes removing the biomass from the vessel 110, where the microalgae are in their growth stage. Extra microalgal biomass (i.e., microalgal biomass of a volume providing for more than an optimum density of microalgal biomass within vessel 110 to provide for a maximum amount of CO2 removal and / or a maximum amount of O2 production) may be dewatered (e.g., including filtration, flocculation, centrifugation) stored in a conversion unit and replaced by cell culture medium. Harvested microalgalbiomass may be dewatered and converted to a nutrient-rich stream and stored (e.g., in a storage unit, optionally with to supplementary media and / or nutrients (such as but not limited to calcium, magnesium, phosphorus, vitamins, iron and micronutrients).

[0054] More specifically, vessel 110 includes a first outlet 152 configured to withdraw liquid biomass collecting within the vessel 110. The liquid biomass generally include biological matter including now dead microalgae. First outlet 152 includes a valve to control the withdrawal of biomass from vessel 110.

[0055] Once the biomass is removed from vessel 110, the biomass passes to a dewatering unit 150. In the dewatering or filtration unit 150, water is removed from the biomass. Dewatering unit 150 may include a flocculation unit, a centrifuge or otherwise be configured to conduct another dewatering process to remove substantially all of the water from the biomass received from the vessel 110. Removed water is collected into stream 156. Dewatered biomass is removed via stream 154 and transported to a conversion unit 160. Stream 156 may also be returned to the vessel 110.

[0056] Conversion unit 160 is configured to convert the dewatered biomass received via stream 154 to a nutrient-rich stream that can be provided into the vessel 110 by third inlet 146. The nutrient-rich stream includes nutrients that typically increase growth of the microalgae within vessel 110. The nutrient-rich stream may enter the vessel 110 above or below a surface of the culture containing medium.

[0057] Conversion unit 160 may include a pyrolysis / anerobic digestion / fermentation unit for converting the dewatered biomass into a nutrient-rich stream.

[0058] In at least one embodiment, hydrolysis may occur in the conversion unit 160. Hydrolysis may include the addition of one or more enzymes or bacteria to conversion unit 160 to produce an ammonia-rich nutrient-rich stream.

[0059] In at least one embodiment, anaerobic digestion may include the addition of one or more enzymes or bacteria to conversion unit 160 to produce a nitrogen-rich nutrient-rich stream. Generally, nitrogen-rich streams may require microalgae to break them down in the vessel 110, which may consume O2. Accordingly, it may be desirableto add nitrogen-rich streams to the vessel 110 at times when there is less O2 present therein.

[0060] Conversion unit 160 may include a hydrolysis (anerobic digestion / Fermentation) unit for converting the dewatered biomass into a nutrient-rich stream.

[0061] Conversion unit 160 may include a secondary storage vessel (not shown) fluidly coupled to either the pyrolysis unit or the hydrolysis or anerobic digestion unit to store the nutrient-rich stream so that it can be controllably added to the vessel 100 in response to the controller 170 determining that the cell culture media in the vessel 110 requires additional media (as described in greater detail below).

[0062] Photobioreactor 100 also includes a controller 170 and a plurality of sensors and / or probes for monitoring and / or controlling growth conditions within the vessel 110.

[0063] Controller 170 is configured to continuously monitor various parameters (i.e., environmental parameters) within the vessel 110, including but not limited to: pH, inlet CO2 concentration, inlet CO2 volume, outlet CO2 concentration, outlet CO2 volume, inlet O2 concentration, inlet O2 volume, biomass density (e.g., concentration), nitrogen concentration, phosphorus concentration, light intensity, light wavelength, temperature and inline biomass detector (e.g., to measure a density of cells within the cell culture media.

[0064] More specifically, photobioreactor 100 includes at least the following sensors / probes:• an inlet CO2 sensor 180 configured to measure a flow rate and / or concentration of CO2 entering the vessel 110 via inlet 114;• an inlet O2 sensor 181 configured to measure a flow rate and / or concentration of O2 entering the vessel 110 via inlet 114;• an outlet CO2 sensor 182 configured to measure a flow rate and / or concentration of CO2 exiting the vessel 110 via outlet 122;• an outlet O2 sensor 183 configured to measure a flow rate and / or concentration of O2 exiting the vessel 110 via outlet 122;• a pH sensor 184 configured to measure a pH of the cell culture media within the vessel 110;• a temperature sensor 185 configured to measure a temperature of the cell culture media and / or air space above the cell culture media within the vessel 110;• a cell density sensor 186 configured to measure a cell density of the cell culture media within the vessel 110 (e.g., measure a number of cells within the media, for example by a spectrophotometer);• a nutrient concentration sensor 187 configured to measure a concentration of one or more nutrients within the cell culture media within vessel 110 (e.g., phosphorus and / or nitrogen);• a light intensity sensor 188 configured to measure an intensity and / or frequency of the light within the vessel 110.

[0065] For ease of illustration, some of the aforementioned sensors have been shown as a single sensor in FIG. 1. However, it should be understood that each sensor may be a separate and distinct sensor.

[0066] In at least one embodiment, the controller 170 is communicatively coupled to each of the sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188 to receive sensor data from one or more of the sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188 and, based on the received data.

[0067] Controller 170 is also communicatively coupled to each of the following components to control each of the following components of photobioreactor 100: inlet 114; outlet 122; heat exchanger 126; agitator (aeration) 128; lights 140; inlet 142; inlet 144; inlet 146; and outlet 152.

[0068] Controller 170 is arranged to enable automated control of components of bioreactor 100. Controller 170 may include a processor running artificial intelligence(Al) and / or machine learning (ML), neural networks, Bayesian networks, and / or fuzzy logic to process sensor data received from the plurality of sensors and / or probes present in vessel 110 and control various environmental parameters of photobioreactor 100 including but not limited to inlet air flow rates, temperature, nutrient concentrations, pH levels, dissolved gases concentrations, and / or light intensity. Controller 170 may implement Artificial Neural Networks (ANN) and / or Deep-learning architectures such as deep neural networks, deep belief networks, recurrent neural networks and convolutional neural networks to dynamically adjust environmental conditions within photobioreactor 100. Controller 170 may implement supervised learning. Controller 170 may create multiple decision trees that solve multiple cultivation optimization problems. Controller 170 may use Bayesian networks to optimize an microalgae growth and / or conversion of CO2 to O2.

[0069] Controller 170 is configured to control one or more of the aforementioned components of the photobioreactor 100 to optimize growth conditions of the microalgae, for example for consuming CO2 and generating O2.

[0070] In at least one embodiment, the controller 170 is configured to, in response to receiving sensor data from one or more of the sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188, determine if a corrective action should be taken to optimize at least one of CO2 consumption and O2 generation within the vessel 110 of photobioreactor 100.

[0071] The determination of whether or not a corrective action should be taken to optimize at least one of CO2 consumption and O2 generation within the vessel 110 of photobioreactor 100 may be based on comparing one or more of the data received from the one or more of the sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188 to a preselected value for the parameter of the one or more of the sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188.

[0072] If the controller determines that a corrective action should be taken to optimize at least one of CO2 consumption and O2 generation within the vessel 110 of photobioreactor 100, controller 170 may apply a model to the sensor data received from the one or more of the sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188 to determinethe corrective action to take to optimize at least one of CO2 consumption and O2 generation within the vessel 110 of photobioreactor 100.

[0073] More specifically, with respect to the air inlet 114, the controller 170 may be configured to control the air inlet 114 to increase and / or decrease a volume of air received into the vessel 110.

[0074] With respect to the air outlet 122, the controller 170 may be configured to control the air outlet 122 to increase and / or decrease a volume of air removed from the vessel 110.

[0075] With respect to the temperature, heat exchanger 126 may optionally be placed near inlet of air 114, the controller 170 may be configured to control the heat exchanger 126 and direct the heat exchanger 126 to increase or decrease a temperature inside of vessel 110.

[0076] With respect to the agitator 128, the controller 170 may be configured to control the agitator 128 to increase or decrease a rate of circulation of cell culture media within the vessel 110.

[0077] With respect to light source 140, the controller 170 may be configured to control the light source 140 to control whether the lights are on or off and / or the intensity or the frequency of light from light source 140.

[0078] With respect to the water inlet 142, the controller 170 may be configured to control a volume of supplemental water added to the vessel 110.

[0079] With respect to the nutrient inlet 144, the controller 170 may be configured to control a volume of supplemental nutrients added to the vessel 110. Supplemental nutrients may include but are not limited to vitamins, iron, calcium, magnesium, and other micronutrients.

[0080] With respect to the nutrient-rich inlet 146, the controller 170 may be configured to control a volume and / or flow rate of nutrient-rich stream added to the vessel 110.

[0081] With respect to the biomass harvesting outlet 152, the controller 170 may be configured to control the biomass harvesting outlet 152 to increase or decrease a volume of biomass removed from the vessel 110.

[0082] Some embodiments of the device may use data from the one or more of the sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188 to determine a replacement period of the photobioreactor 100. For example, cell density sensor 186 (e.g., a spectrophotometer) may be used to determine the density of cells with in the cell culture medium of the vessel 110. When the cell density exceeds a preselected value, the controller 170 may control the outlet valve 152 to increase a flow rate of the biomass removed from the vessel 110.

[0083] The pre-selected values for various parameters of the system may vary depending on the species of microorganism used to encourage photosynthesis and its pigmentation profile.

[0084] FIG. 3 includes a block diagram of a computer system 200 for performing the functions of a computer such as for the controller 170 of FIG. 1 . The exemplary computer system 200 includes a central processing unit (CPU) 202, a memory 204, and an interconnect bus 206. The CPU 202 may include a single microprocessor or a plurality of microprocessors for configuring computer system 200 as a multi-processor system. The memory 204 includes a main memory and a read only memory. The computer 200 also includes a mass storage device 208 having, for example, various disk drives, tape drives, etc. The main memory 204 may include dynamic random access memory (DRAM) and high-speed cache memory. In operation, the main memory 204 stores at least portions of instructions and data to be executed by CPU 202.

[0085] Mass storage 208 may include one or more magnetic disk or tape drives or optical disk drives or solid state memory, for storing data and instructions for use by the CPU 202. At least one component of the mass storage system 208 stores the database used for processing sensor data from sensors 180, 181 , 182, 183, 184, 185, 186, 187, 188 (as well as other sensors that may optionally be included) and running Al and / or ML engines and / or neural networks for controlling photobioreactor 100. The Aland / or ML engines may implement ANNs and / or Deep-learning architectures such as deep neural networks, deep belief networks, recurrent neural networks and convolutional neural networks to dynamically adjust environmental conditions within photobioreactor 100.

[0086] To effect automated control of photobioreactor 100, computer 200 may send sensor control signals to various components of photobioreactor 100, as shown in FIG. 1 , such as but not limited to either, opening, closing, turning on, turning off, adjusting flow rates, adjusting mixing rates, and / or adjusting light intensity of light source(s), to optimize conversion of CO2 to O2 within photobioreactor 100.

[0087] The mass storage system 208 may also include one or more drives for various portable media, such as a floppy disk, flash drive, a compact disc read only memory (CD- ROM, DVD, CD-RW, and variants), memory stick, or an integrated circuit non-volatile memory adapter (i.e., PC-MCIA adapter) to input and output data and code to and from the computer system 200. In some implementations, computer 200 and / or controller 170 may control multiple photobioreactors concurrently via a data network such as network 212. Controller 170 may coordinate operations among the multiple photobioreactors to optimize output production and / or yield among the multiple photobioreactors. Network 212 may include a wireless, Adhoc, and / or mobile network, supporting multiple computing servers implementation a cloud computing environment.

[0088] The computer system 200 may also include one or more input / output interfaces for communications, shown by way of example, as interface 210 and / or transceiver for data communications via the network 212. The data interface 210 may be a modem, an Ethernet card or any other suitable data communications device. To provide the functions of a computer , the data interface 210 may provide a relatively high-speed link to a network 212, such as an intranet, or the Internet, either directly or through another external interface. The communication link to the network 212 may be, for example, optical, wired, or wireless (e.g., via satellite or cellular network). Alternatively, the computer system 200 may include a mainframe or other type of host computer system capable of Web-based communications via the network 212. The computer system 200may include software for operating a network application such as a web server and / or web client.

[0089] Computer system 200 may also include suitable input / output ports, that may interface with a portable data storage device, or use the interconnect bus 206 for interconnection with a local display 216 and input device 214 (e.g., keyboard, touchpad or the like serving) as a local user interface for programming and / or data retrieval purposes. The display 216 and / or display 120 may include a touch screen capability to enable users to interface with the system 200 by touching portions of the surface of the display 216. Remote operations personnel may interact with the system 200 for controlling and / or programming the system from remote terminal devices via the network 212.

[0090] Computer system 200 may run a variety of application programs and store associated data in a database of mass storage system 208. One or more such applications may include a photobioreactor controller 170 that controls various components of photobioreactor 100.

[0091] Culture Medium

[0092] In an embodiment of the invention, to prepare a liquid mixture (not shown) for use, a user dilutes microalgae in water. The user then adds the diluted food to the liquid. The user fills the rest of the vessel with water.

[0093] The device may utilize standard photosynthetic microorganisms or microalgae types, such as the type which can be purchased from scientific lab suppliers. The device may also utilize specially-designed photosynthetic microorganisms or algae. For example, the microorganism could be nannochloropsis, chlorella, other eukaryotic algae, and many other strains of cyanobacteria such as Synechococcus or Spirulina. In alternative embodiments, microalgae may be used. In at least one embodiment, microalgae are used. The microalgae may be of one of the following types of microalgae: freshwater microalgae, marine microalgae, brackish water microalgae, and extremophile microalgae.

[0094] Vessel 110 may also include one or more electrical components for powering the photobioreactor 110 and / or components therein. The photobioreactor 110 may have an electrical cord drawing standard household power (typically 110-120 VAC) to power the device. Other embodiments of the device use other standard forms of energy. For example, solar panels or battery powered. In some embodiments, the bioreactor may include one or more generators that produce electricity from sunlight, commonly known as solar generators. These devices use solar panels to capture sunlight and convert it into electrical energy, which is then stored in a battery. The stored energy can be used to power various devices and appliances when needed.

[0095] In some embodiments, oxygen generation may not be a priority to produce in the bioreactor. Alternatively, hydrogen generation may be desirable. Hydrogen may be produced by the photobioreactor 100 to be used as a fuel, for example, in an alternate application. Among these, Chlamydomonas reinhardtii is particularly well-known for its ability to produce hydrogen and is often used as a model organism in biohydrogen research.

[0096] In some embodiments, it is known that microalgae suitable for promoting the conversion of CO2 to O2 may have various growth sages or phases, such as but not limited to a growth stage and a rest stage. The microalgae may require a rest stage, for example is a range of about 1 to 6 hours in each 24 hour period, to recover from their growth stage and not become overstressed. In some embodiments, controller 170 may be configured to monitor a growth stage of the microalgae and optimize other environmental parameters in response to the growth stage of the microalgae. In one embodiment, the controller 170 may monitor a growth stage of the microalgae based on optical sensor data. For example, the microalgae may change colour when they are in different growth stages and the optical sensor may detect this colour change. In response, the controller 170 may optimize other conditions of the photobioreactor 100 based on the growth stage (e.g., may turn off the light source when the microalgae are in a rest stage, turn on the light source when they enter a growth stage, etc.).

[0097] In at least one embodiment, methane may be produced during the conversion of CO2 to 02 by the microalgae. In at least one embodiment, methane generated by the conversion of CO2 to 02 by the microalgae can be captured.

[0098] In at least one embodiment, the nutrient-rich stream, which in at least one embodiment is an ammonia-rich (e.g., greater than 50% ammonia-based compounds) nutrient-rich stream, may be added to the vessel 110 during a rest stage of the microalgae and / or at night (when light exposure of the microalgae is below a predetermined threshold). Ammonia-rich nutrients may absorb O2 generated by the photobioreactor and, in at least one embodiment, it may be desirable to add nutrient-rich stream to the microalgae in vessel 110 when they are less active (e.g., at night) to minimize any oxygen absorption that may otherwise occur if the nutrient-rich stream were added to the vessel 110 during a growth phase of the microalgae.

[0099] During the night / dark phase, the microalgae try to decompose organic compound to inorganic compounds such as nitrate and phosphate; this nutrient is added during the night cycle.

[0100] Photobioreactor 100 may optionally include ultrasonic technologies or (aeration near the wall, blade / agitator as an agitator to not allow the dead cells stick in the wall) to detach microalgae from interior walls of the vessel 110. In at least one embodiment, the ultrasonic technology could be communicatively couped to the controller 170 and activated by the controller 170 in response to the controller 170 receiving data from the one or more sensors indicating that a cell density of the cell culture medium exceeds a preselected value. In another example, the ultrasonic technology could be controlled to be activated at preselected time intervals. For instance, the ultrasonic technology or aeration could be activated to remove microalgae build-up on interior surfaces of the walls of the vessel 110 shortly before harvesting biomass from vessel 110.

[0101] Turning now to FIG. 4, shown therein is flow chart of a method 300 of operating a photobioreactor.

[0102] Method 300 includes, at first step 302 provide a photobioreactor housing microalgae. One example of a suitable photobioreactor is photobioreactor 100 described herein.

[0103] At second step 304, method 300 includes providing CO2 to the photobioreactor. CO2 may be provided in the form of atmospheric air, for example.

[0104] At third step 306, a controller of the photobioreactor may control one or more environmental parameters of the photobioreactor, such as but not limited to oxygen concentration, carbon dioxide concentration, oxygen output, carbon dioxide output, or the like, from the photobioreactor.

[0105] At fourth step 308, the controller may also monitor one or more additional environmental parameters, such as but not limited to pH levels, phosphorus levels, nitrogen levels, temperature, light, microalgae concentration and / or microalgae growth stage within the bioreactor.

[0106] At fifth step 310, based on the one or more environmental parameters, including but not limited to pH levels, phosphorus levels, nitrogen levels, temperature, light, and the cell density of the microalgae, the controller may be configured to adjust the one or more aspects of the photobioreactor, including but not limited to at least one of opening, closing, turning on, turning off, adjusting a flow rate and adjusting a mixing rate of one or more components of the photobioreactor and / or adjusting a light intensity of light emitters of the photobioreactor, to optimize the cell density of the microalgae, including but not limited to controlling a flow rate of microalgae out of a bottom of the photobioreactor, controlling an inlet of a nutrient-rich stream into the photobioreactor and controlling a flow rate of an inlet stream of CO2 into the photobioreactor.

[0107] While the applicant's teachings described herein are in conjunction with various embodiments for illustrative purposes, it is not intended that the applicant's teachings be limited to such embodiments as the embodiments described herein are intended to be examples. On the contrary, the applicant's teachings described and illustrated herein encompass various alternatives, modifications, and equivalents, without departing fromthe embodiments described herein, the general scope of which is defined in the appended claims.

Claims

CLAIMSWhat is claimed is:

1. A photobioreactor for producing and harvesting microalgae, the photobioreactor comprising: a vessel for cultivating microalgae, the vessel defining an interior chamber comprising a culture containing medium, the vessel having at least one wall being transparent to permit passage of light of a frequency necessary to promote growth of the microalgae in the culture containing medium; a plurality of sensors, each sensor being configured to monitor at least one environmental condition within the photobioreactor; at least one flow generator positioned within the vessel, each flow generator being configured to direct a flow of the culture containing medium within the vessel; and a controller communicatively coupled to each of the plurality of sensors and the at least one flow generator, the controller being configured to: receive sensor data from each of the plurality of sensors, the sensor data including data of at least one environmental parameter within the photobioreactor; apply a mathematical model to the sensor data to determine when to adjust at least one component of the photobioreactor to optimize the at least one environmental condition monitored within the photobioreactor; and in response to determining to adjust the at least one component, adjust the at least one component by at least one of opening, closing, turning on, turning off, adjusting a flow rate into, adjusting a flow rate out of, and adjusting a mixing rate within the photobioreactor and / or adjusting a light intensity of light emitters of the photobioreactor.

2. The photobioreactor of claim 1 , wherein the at least one environmental condition includes at least one of a conversion rate, flow rate, temperature, nutrientconcentration, pH level, dissolved gas concentration, light intensity within the photobioreactor.

3. The photobioreactor of claim 2, wherein the nutrient concentration includes nitrogen concentration and phosphorus concentration.

4. The photobioreactor of claim 2, wherein the dissolved gas concentration includes carbon dioxide concentration and oxygen concentration.

5. The photobioreactor of any one of claims 1 to 4, wherein the controller implements at least one of artificial intelligence, machine learning, and deep learning to optimize predictive analytics for quality control monitoring.

6. The photobioreactor of any one of claims 1 to 5, wherein the vessel is a base of a patio umbrella.

7. The photobioreactor of any one of claims 1 to 6, wherein the vessel is a post and / or a base of a patio umbrella.

8. The photobioreactor of any one of claims 1 to 7, further comprising a dewatering unit configured to receive biomass from the vessel, the dewatering unit configured to remove water from the biomass received from the vessel and produce a dewatered biomass stream.

9. The photobioreactor of claim 8 further comprising a conversion unit configured to receive the dewatered biomass stream and convert the dewatered biomass stream into a nutrient rich-stream for providing to the vessel, conversion unit being configured to perform at least one of pyrolysis, anerobic digestion and fermentation to produce the nutrient-rich stream.

10. The photobioreactor of claim 9 further comprising a nutrient-rich stream inlet configured to control a volume and / or flow rate of the nutrient rich-stream into the vessel, the controller being communicatively coupled to the nutrient-rich stream inlet and configured to open and close the nutrient-rich stream inlet based on an optical density of the culture containing medium in the vessel.

11. The photobioreactor of claim 10 wherein the nutrient-rich stream enters the vessel above a surface of the culture containing medium.

12. The photobioreactor of claim 10 wherein the nutrient-rich stream enters the vessel below a surface of the culture containing medium.

13. The photobioreactor of any one of claims 1 to 13 further comprising a heat exchanger communicatively coupled to the controller, the controller being configured to control a temperature of the culture containing medium with the heat exchanger.

14. The photobioreactor of any one of claims 1 to 14, wherein the environmental condition is conversion of carbon dioxide into oxygen and the controller is configured to optimize conversion of carbon dioxide into oxygen within the vessel by adjust the at least one component of the photobioreactor, and the adjusting include adjusting a flow rate of the nutrient-rich stream into the vessel.

15. A method of operating a photobioreactor, the method comprising: providing a photobioreactor housing microalgae; providing air to a vessel of the photobioreactor, the air including carbon dioxide and oxygen; monitoring one or more parameters of the photobioreactor during photosynthetic conversion of the carbon dioxide to oxygen, the photosynthetic conversion being encouraged by the microalgae, the one or more parameters including an optical density of a cell culture medium including the microalgae; based on at least the optical density of the cell culture medium including the microalgae, controlling a volume of a biomass stream exiting the vessel of the photobioreactor; converting the biomass stream into a nutrient rich stream; and returning at least a portion of the nutrient rich stream to the photobioreactor.

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