System and method for converting gaseous carbon compound into carbon-neutral or carbon-negative product

Abstract

To provide a system and a method for converting a gaseous carbon compound into a carbon-neutral or carbon-negative product.SOLUTION: A system and a method use a biological process of metabolizing a gaseous carbon compound. The gaseous carbon compound includes a mixture of CO2 and CH4 from a single source or two or more of different sources. Separate biological processes are united, and different gaseous carbon compounds are treated. The gaseous carbon compound produced as a subsidiary product of a single biological process is used as a raw material for another biological process or a part thereof. In order to assist minimization of a carbon footprint and facilitation of an overall carbon-negative profile, a recyclable energy system is provided, which gives a driving power to an apparatus and an installation of the system and method.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] Systems and methods are disclosed for converting gaseous carbon compounds into carbon-neutral or carbon-negative products. The gaseous carbon can be derived from one or a combination of sources, including but not limited to fossil fuels, atmospheric extraction, or organic waste processing, such as landfill biogas or animal waste. The carbon-neutral or carbon-negative products can include, but are not limited to, animal feed proteins, pharmaceuticals, and high-value chemicals. [Background technology]

[0002] Growing concerns about global warming have led to substantial research on greenhouse gases. It is widely agreed that to limit temperature rise to below 1.5°C, multiple measures must be implemented to reduce greenhouse gas emissions, particularly carbon dioxide and methane, as well as to reduce their current content in the atmosphere. While the greenhouse effect of carbon dioxide is well known, methane has a global warming potential (GWP) approximately 28 times higher than that of carbon dioxide over a 100-year period. Consequently, reducing methane emissions from its various sources must not be overlooked. In 2021, the United States, the European Union, and 103 other countries launched the Global Methane Pledge, which aims to reduce global methane emissions by at least 30 percent by 2030 from 2020 levels.

[0003] Research has focused on various approaches to utilizing greenhouse gases for valuable products. For example, the Swiss company Climeworks has several operational plants that capture carbon dioxide directly from the atmosphere, with a total annual capacity of 2,000 tons. The captured carbon dioxide is permanently stored through natural underground mineralization. Some companies, such as Carbon Engineering, are developing technologies to convert carbon dioxide into synthetic fuels through multiple reactions. While methane itself is a valuable energy source, 55–70% of methane emissions come from biogenic sources such as livestock farming, landfills, and wetlands, which cannot be captured and used in the same way as natural gas. In several thermochemical technologies, methane is converted using carbon dioxide as a reducing chemical to produce syngas, an important precursor to a variety of chemicals and fuels. Research has revealed that algae, bacteria, and other microorganisms have enormous potential to consume gaseous carbon through photosynthetic or metabolic processes. Until now, the economics of greenhouse gas extraction have been an obstacle to large-scale, commercially viable operations. Summary of the Invention [Problem to be solved by the invention]

[0004] It is believed that the approach of extracting carbon from gaseous compounds and converting them into commercial products as disclosed therein can assist in keeping global warming at, or preferably below, the 1.5°C target.

[0005] The above references to background art do not constitute an admission that such art forms part of the common general knowledge of those skilled in the art, nor are they intended to limit application of the disclosed systems and methods to any particular form of such systems and methods. [Means for solving the problem]

[0006] In one embodiment, an integrated system for converting gaseous carbon compounds to carbon-neutral or carbon-negative products is disclosed, said integrated system comprising: a source capable of producing a mixture of gaseous carbon feedstocks comprising carbon dioxide and methane; a biological methane treatment system containing methane-metabolizing microorganisms and supplied with methane from the source, the biological methane treatment system being configured to propagate the methane-metabolizing microorganisms and produce carbon dioxide as a by-product; a biological carbon dioxide treatment system containing carbon dioxide metabolizing microorganisms and supplied with carbon dioxide from a source of a mixture of a gaseous carbon source and said carbon dioxide by-product, the biological carbon dioxide treatment system being adapted to propagate the carbon dioxide metabolizing microorganisms; a microorganism harvesting and processing system configured to harvest the propagated microorganisms and produce single-cell proteins; Includes.

[0007] In one embodiment, the methane-metabolizing microorganism comprises a mesophilic methanotrophic bacterium.

[0008] In one embodiment, the carbon dioxide metabolizing microorganism includes a mesophilic bacterium.

[0009] In one embodiment, the carbon dioxide metabolizing microorganism includes a cyanobacterium.

[0010] In one embodiment, the carbon dioxide metabolizing microorganism includes a hydrogen-utilizing bacterium.

[0011] In one embodiment, the integrated system includes an air separation unit capable of producing gaseous oxygen, and the integrated system is arranged to supply the gaseous oxygen to one or both of the biological methane treatment system and the biological carbon dioxide treatment system.

[0012] In one embodiment, the integrated system includes a water splitting unit capable of producing gaseous oxygen, and the integrated system is configured to supply the gaseous oxygen to one or both of the biological methane treatment system and the biological carbon dioxide treatment system.

[0013] In one embodiment, the integrated system includes a water separation unit capable of producing gaseous hydrogen, and the integrated system is arranged to supply the gaseous hydrogen to one or both of the biological methane treatment system and the biological carbon dioxide treatment system.

[0014] In one embodiment, the integrated system includes a cooling system operable to cool one or both of the biological methane treatment system and the biological carbon dioxide treatment system to operate within a predetermined temperature range.

[0015] In one embodiment, the microorganism harvesting and processing system includes a first harvesting system for harvesting microorganisms from the biological methane processing system, a second harvesting system for harvesting microorganisms from the biological carbon dioxide processing system, and a common dryer for drying the harvested microorganisms harvested by both the first and second harvesting systems.

[0016] In one embodiment, the integrated system includes a renewable energy system capable of converting energy from one or more renewable energy sources into one or more forms of controlled energy, and one or both of the biological methane treatment system and the biological carbon dioxide treatment system are powered by the controlled energy.

[0017] In one embodiment, one or more of the water splitting unit, the air separation unit, the cooling system, and the microbial harvesting and processing system are powered by the controlled energy.

[0018] In a second aspect, an integrated biological method for converting gaseous carbon compounds to carbon-neutral or carbon-negative products is disclosed, the method comprising: supplying gaseous methane from a first biogas source to a biological methane treatment system capable of growing methanotrophic bacteria and producing carbon dioxide as a by-product; (a) supplying gaseous carbon dioxide from the first biogas source and (b) the carbon dioxide by-product to a biological carbon dioxide treatment system capable of growing carbon dioxide metabolizing bacteria; producing single-cell proteins from the propagated methanotrophic bacteria and the propagated carbon dioxide metabolizing bacteria; Includes.

[0019] In one embodiment, providing the gaseous methane and providing the gaseous carbon dioxide from the first biogas source includes providing biogas comprising a mixture of gaseous methane and gaseous carbon dioxide from the first biogas source to a gas pre-treatment and separation unit, and operating the gas pre-treatment and separation unit to provide separate gaseous methane and gaseous carbon dioxide feed streams.

[0020] In one embodiment, the method includes supplying gaseous oxygen to the biological methanation system.

[0021] In one embodiment, the method includes supplying gaseous oxygen to the biological carbon dioxide treatment system.

[0022] In one embodiment, the method includes supplying gaseous hydrogen to the biological carbon dioxide treatment system.

[0023] In one embodiment, the method includes using a hydrogen-utilizing bacterium as the carbon dioxide metabolizing bacterium.

[0024] In one embodiment, the method includes using a cyanobacterium as the carbon dioxide metabolizing bacterium.

[0025] In one embodiment, the method includes supplying one or more nutrients to one or both of the biological methane treatment system and the biological carbon dioxide treatment system.

[0026] In one embodiment, the method includes cooling one or both of the biological methane treatment system and the biological carbon dioxide treatment system to operate within a predetermined temperature range.

[0027] In one embodiment, providing gaseous oxygen includes producing gaseous oxygen from one or both of (a) an air separation unit, and (b) a water splitting unit.

[0028] In one embodiment, providing the gaseous hydrogen comprises operating a water splitting unit to produce the provided gaseous hydrogen.

[0029] In one embodiment, producing the single-cell protein comprises harvesting and drying the propagated methanotrophic bacteria and the propagated carbon dioxide metabolizing bacteria.

[0030] In one embodiment, the method includes generating motive power from one or more renewable energy sources and using the generated motive power as operating power for plant and equipment used to enable the method to be carried out.

[0031] In a third aspect, a method of animal husbandry is disclosed, said method comprising: producing biogas comprising a mixture of gaseous methane and carbon dioxide from waste excreted by the plurality of animals; converting the biogas into single cell proteins using the method according to the second aspect; feeding the plurality of animals a feed comprising the single-cell protein; Includes.

[0032] In a fourth aspect, a carbon processing system for generating one or more carbon-neutral products is disclosed, the system comprising: a renewable energy system capable of converting energy from one or more renewable energy sources into one or more forms of controlled energy; one or more sources of gaseous carbon compounds; one or more reactant feed streams; a carbon processing plant powered by said controlled energy and configured to convert said gaseous carbon compounds in the presence of said one or more reactants to produce one or more saleable products; Includes.

[0033] In one embodiment of the fourth aspect, the one or more sources of gaseous carbon compounds include a direct air carbon capture system powered by the renewable energy system.

[0034] In one embodiment of the fourth aspect, the one or more sources of gaseous carbon compounds include a methane source.

[0035] In one embodiment of the fourth aspect, the methane source comprises an oil or gas reservoir.

[0036] In one embodiment of the fourth aspect, the methane source comprises coal seam gas.

[0037] In one embodiment of the fourth aspect, the methane source comprises biowaste.

[0038] In one embodiment of the fourth aspect, the reactants include one or more of oxygen, hydrogen, and water.

[0039] In one embodiment of the fourth aspect, the carbon processing system includes an air separation unit for producing oxygen, the air separation unit being powered by the renewable energy system.

[0040] In one embodiment of the fourth aspect, the carbon processing system includes a water splitting unit for producing oxygen or hydrogen, the water splitting unit being powered by the renewable energy system.

[0041] In one embodiment of the fourth aspect, the carbon processing system includes a methane pyrolysis unit for producing hydrogen, the methane pyrolysis unit being powered by the renewable energy conversion system.

[0042] In one embodiment of the fourth aspect, the carbon processing plant includes one or more carbon processing units arranged to process the gaseous carbon compound in the presence of one or more of the reactants to produce the one or more saleable products.

[0043] In one embodiment of the fourth aspect, the one or more carbon processing units comprise a bioreactor for biologically treating the gaseous carbon compounds.

[0044] In one embodiment of the fourth aspect, the one or more carbon processing units include a separation unit arranged to separate carbon from other elements within the gaseous carbon compound.

[0045] In one embodiment of the fourth aspect, at least one of the carbon processing units is arranged to produce gaseous carbon dioxide, and the carbon capture and processing system is arranged to supply the produced carbon dioxide to at least one other of the carbon processing units.

[0046] In one embodiment of the fourth aspect, the renewable energy system includes a concentrated solar thermal plant that heats a fluid heat transfer and storage medium.

[0047] In one embodiment of the fourth aspect, the renewable energy system includes a photovoltaic array for producing electricity to power the carbon capture and treatment system.

[0048] In one embodiment of the fourth aspect, the renewable energy system is arranged to store energy to enable daily operation of the carbon capture and treatment system.

[0049] In a fifth aspect, a carbon processing method for generating one or more carbon-neutral products is disclosed, the method comprising: Producing energy using renewable energy; providing one or more gaseous carbon compounds to a carbon processing plant; providing one or more reactants to the carbon processing plant; using the produced energy to power at least the carbon processing plant; operating the carbon processing plant to convert the gaseous carbon compounds in the presence of the one or more reactants into one or more saleable carbon-neutral products; Includes.

[0050] In one embodiment of the fifth aspect, providing the one or more gaseous carbon compounds comprises providing gaseous carbon dioxide derived from any one or more of: (a) a direct air carbon capture system powered by the produced energy; (b) fossil fuel production, processing, or combustion; and (c) a by-product or waste product of an industrial process, including cement manufacturing or ammonia production.

[0051] In one embodiment of the fifth aspect, providing a gaseous carbon compound includes providing methane to said carbon processing plant.

[0052] In one embodiment of the fifth aspect, supplying methane includes supplying methane sourced from an oil or gas reservoir.

[0053] In one embodiment of the fifth aspect, providing methane includes providing coalbed-sourced methane.

[0054] In one embodiment of the fifth aspect, providing methane includes providing biowaste-sourced methane.

[0055] In one embodiment of the fifth aspect, said providing one or more reactants comprises providing one or more of oxygen, hydrogen, and water feed streams.

[0056] In one embodiment of the fifth aspect, supplying oxygen includes supplying oxygen produced by an air separation unit powered by said produced energy.

[0057] In one embodiment of the fifth aspect, supplying oxygen comprises supplying oxygen produced by a water splitting unit powered by said produced energy.

[0058] In one embodiment of the fifth aspect, supplying hydrogen includes supplying hydrogen produced by a water cracking unit or a methane pyrolysis unit powered by the produced energy.

[0059] In one embodiment of the fifth aspect, the method includes forming the carbon processing plant as one or more carbon processing units, each capable of processing the gaseous carbon compound in the presence of one or more of the reactants to produce the one or more saleable products or precursors to saleable products.

[0060] In one embodiment of the fifth aspect, at least one of the carbon processing units is arranged to biologically treat said gaseous carbon compounds.

[0061] In one embodiment of the fifth aspect, at least one of the carbon processing units is a separation unit arranged to separate carbon from other elements in the gaseous carbon compounds.

[0062] In one embodiment of the fifth aspect, gaseous carbon dioxide produced as a waste product by a process within said carbon processing plant is supplied back to said carbon processing plant.

[0063] In one embodiment of the fifth aspect, the method comprises operating the renewable energy system as a concentrated solar thermal plant, and the energy produced is thermal energy carried thereby in a flowable heat transfer medium.

[0064] In one embodiment of the fifth aspect, the method includes operating the renewable energy system in a manner such that the produced energy includes electrical energy.

[0065] In one embodiment of the fifth aspect, the method includes storing at least a partial proportion of the produced energy and subsequently using the stored energy to enable daily operation of the carbon capture and treatment system.

[0066] In one embodiment of the fifth aspect, the method includes monitoring and controlling the flow of the gaseous carbon compound and the reactants to the carbon processing units to provide mass-balanced amounts of the gaseous carbon compound and the reactants for processing in each carbon processing unit.

[0067] In a sixth aspect, an integrated system for converting gaseous carbon compounds to carbon-neutral or carbon-negative products is disclosed, said integrated system comprising: a renewable energy system capable of converting energy from one or more renewable energy sources into one or more forms of controlled energy; one or more sources of one or more gaseous carbon compounds; one or more reactant feed streams; a carbon processing plant powered by the controlled energy and configured to convert the gaseous carbon compounds in the presence of the one or more reactants to produce one or more saleable products, the carbon processing plant having a first carbon processing unit capable of producing a first saleable product and a gaseous carbon compound by-product from at least one of the gaseous carbon compounds, and a second carbon unit capable of producing a second saleable product from the gaseous carbon compound by-product; Includes.

[0068] In one embodiment, one or both of the first and second carbon processing units includes a bioreactor that biologically processes the gaseous carbon compounds.

[0069] In one embodiment, the first carbon processing unit is a biological methane processing system containing methane-metabolizing microorganisms, and the gaseous carbon compound by-product is carbon dioxide.

[0070] In one embodiment, the methane-metabolizing microorganism comprises a mesophilic methanotrophic bacterium.

[0071] In one embodiment, the second carbon processing unit is a biological carbon dioxide processing system containing carbon dioxide metabolizing microorganisms.

[0072] In one embodiment, the carbon dioxide metabolizing microorganism includes a mesophilic bacterium.

[0073] In one embodiment, the carbon dioxide metabolizing microorganism includes a cyanobacterium.

[0074] In one embodiment, the carbon dioxide metabolizing microorganism includes a hydrogen-utilizing bacterium.

[0075] In one embodiment, the integrated system includes a third carbon processing unit capable of producing a third saleable product, the third carbon processing unit being a biological carbon dioxide processing system including carbon dioxide metabolizing microorganisms, the carbon dioxide metabolizing microorganisms of the second carbon processing unit including hydrogenotrophic bacteria, and the carbon dioxide metabolizing microorganisms of the third carbon processing unit including cyanobacteria.

[0076] In one embodiment, the carbon processing plant includes a synthesis gas generation unit capable of producing synthesis gas from the one or more gaseous carbon compounds and by-products of the gaseous carbon compounds.

[0077] In a seventh aspect, a system for converting gaseous carbon compounds to carbon-neutral or carbon-negative products is disclosed, the system comprising: a renewable energy system capable of converting energy from one or more renewable energy sources into one or more forms of controlled energy; one or more sources of methane and carbon dioxide; a synthesis gas generation unit capable of forming synthesis gas from said methane and carbon dioxide, said synthesis gas generation unit being powered by said controlled energy; a syngas conversion unit configured to convert the syngas into carbon-neutral or carbon-negative products; Includes.

[0078] In one embodiment, the syngas conversion unit is a bioreactor capable of fermenting the syngas.

[0079] In one embodiment, the synthesis gas conversion unit is arranged to carry out a thermochemical process to produce hydrocarbons.

[0080] While any other format may fall within the scope of the systems and methods as set forth in the Summary, specific embodiments are described below, by way of example only, and with reference to the appropriate figures listed below. [Brief explanation of the drawings]

[0081] [Figure 1] FIG. 1 is a flow diagram generally illustrating one embodiment of the disclosed system and method for converting gaseous carbon compounds into carbon-neutral or carbon-negative products. [Figure 2] FIG. 2 is a more detailed flow diagram of the method and system shown in FIG. 1. [Figure 3]FIG. 1 is a flow diagram of a second embodiment of the systems and methods of the present disclosure, which may be designated as an integrated system and method for converting gaseous carbon compounds to carbon-neutral or carbon-negative products, where the gaseous carbon compounds include a mixture of methane and carbon dioxide generated from a single source. [Figure 4] FIG. 4 is a mass flow diagram for the embodiment shown in FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0082] Specific embodiments of the disclosed systems and methods will now be described for illustrative purposes only. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the disclosed systems and methods. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the systems and methods pertain. It will be understood that in the drawings, like reference numerals refer to like parts.

[0083] The general concept disclosed herein provides systems and methods for converting gaseous carbon compounds into carbon-neutral or carbon-negative products. The gaseous carbon compounds can be provided from one or more sources. A source can provide a single gaseous carbon compound, e.g., CO2 or CH4; or a mixture of gaseous carbon compounds, e.g., both CO2 and CH4. Separate biological processes can be combined to process different gaseous carbon compounds. Gaseous carbon compounds produced as waste products from one biological process can be used as feedstock for, or as part of, another biological process.

[0084] The systems and methods also contemplate providing feedstreams of other reactants, such as oxygen, hydrogen, and water, to facilitate processing of the gaseous carbon compounds. Processes that consume the gaseous carbon compounds include, but are not limited to, biological reactions such as metabolism / fermentation and / or chemical dissociation. In some embodiments, only biological processes are used to consume the gaseous carbon compounds. To help minimize the carbon footprint and enable an overall carbon-negative profile, various embodiments of the disclosed integrated systems and methods can provide renewable energy systems to power individual processes, systems, and devices.

[0085] FIG. 1 generally illustrates in flow diagram form an embodiment of the disclosed system 10 and associated method 12 for capturing gaseous carbon compounds and processing the carbon to produce valuable products.

[0086] In system 10 and method 12, energy from one or more renewable energy sources is converted by renewable energy system 14 into one or more forms of energy that are controlled and used to power downstream plants, equipment, and processes. For example, renewable energy system 14 may be arranged to produce both thermal energy and electricity. Energy conversion system 14 may also include energy storage facilities, such as a volume of molten salt or particulate material for storing heat or a battery for storing electricity. Depending on the application, the energy storage facilities will be adapted to enable 24 / 7 operation of system 10.

[0087] One or more gaseous carbon compounds CX are provided to the carbon processing plant 20 by one or more gaseous carbon sources CS. The gaseous carbon compounds can be different compounds / gases, such as carbon dioxide and methane. The gaseous carbon source CS can include a single source or a combination of sources. The gaseous carbon source can also provide a mixture of two or more different gaseous carbon compounds. For example, the gaseous carbon source CS can include a biogas source that provides a mixture of methane and carbon dioxide (as well as other non-carbon gases such as nitrogen, hydrogen sulfide, and ammonia).

[0088] Energy from system 14 can be used to power one or more of gaseous carbon sources CS, which convert or process materials to produce gaseous carbon compound stream CX. Stream CX is supplied to carbon processing plant 20. The carbon processing plant can have a number of different processing systems that produce a wide range of different products P1-Pn. Different processes within the carbon processing unit are arranged to process different types of gaseous carbon compounds or to perform different processes on gaseous carbon compounds to produce different products P1-Pn. Energy to operate carbon processing plant 20 is provided by renewable energy system 14.

[0089] Other reactants and / or nutrients may be provided to carbon processing plant 20 to facilitate or enhance a particular process for producing a particular product P1-Pn. Examples of reactants include one or more of oxygen, hydrogen, nitrogen, and water provided by respective feed streams 24, 26, 27, and 28. Nutrients, when provided, may include macronutrients and / or micronutrients. As described below, one or more of the reactants may be produced by respective reactant generation units RU. The units RU may be powered by renewable energy system 14.

[0090] Products P1-Pn may include single-cell proteins that can be used as animal feed, artificial meat for human consumption, pharmaceuticals, and high-value chemicals such as ethanol, isopropanol, and palm oil.

[0091] Figure 2 illustrates in more detail the overall system 10. In describing system 10, the use of the same reference numbers as in Figure 1 indicates the same features.

[0092] The renewable energy system 14 can provide energy to all plants and equipment in the system 10. Additionally, the energy system 14 can be configured to provide different forms of energy to different plants and equipment in the system 10. For example, in one embodiment, the energy system 14 can include a concentrated solar thermal (CST) plant that heats a flowing fluid heat transfer and storage medium, such as molten salt, in a temperature range between, for example, 500° C. and 700° C. Alternatively, or in addition, the renewable energy system 14 can include one or a combination of one or more of an array of photovoltaic cells, a wind turbine, and a geothermal source.

[0093] The carbon source CS in Figure 1 is shown in Figure 2 as three different sources of gaseous carbon compounds. These are: a direct air carbon capture system (DAC) 16 powered by a renewable energy system 14; and a carbon dioxide source 31, which may include a supply of carbon dioxide as a by-product or waste product of an industrial process such as cement production or an ammonia plant, or the combustion of hydrocarbons; A methane source 36 which may include methane as biogas produced by the processing of hydrocarbons or generated by the decomposition of organic waste. In the case where the methane source is a biogas source, the source 36 will provide, in addition to methane, gaseous carbon dioxide which can be processed by the treatment plant 20.

[0094] The direct air carbon capture system 16 can use a carbon absorbent material such as zeolite. The zeolite can be arranged in different banks that are heated and cooled at different times. At relatively low temperatures, the carbon absorbent material captures carbon dioxide from the air. Upon heating, the captured carbon dioxide is released from the carbon absorbent material at a concentration substantially higher than that found in the air. By appropriately controlling the heating and cooling cycles of the different banks of zeolite or other carbon absorbent material, a relatively constant carbon dioxide feed stream 18 can be produced.

[0095] The heated molten salt from the energy system 14 can be circulated directly through the carbon-from-air capture system 16 to heat the zeolite and liberate carbon dioxide. When the energy system 14 includes a CST plant, the system 10 can also include a storage tank (not shown) for the heated molten salt, allowing for continuous circulation throughout the daily cycle. Alternatively, electric heaters powered by photovoltaic cells and / or electricity from wind turbines and / or geothermal sources can be used to heat the zeolite.

[0096] The renewable energy system 14 can also provide electrical energy to the carbon processing plant 20 and other equipment in the system 10. This can be accomplished in many different ways. For example, a heat transfer medium can be used to heat water to produce steam, which then drives a turbine connected to a generator to produce electrical energy, which is stored in an on-site battery. Alternatively, or in addition, the renewable energy system 14 can also include a photovoltaic array to charge the battery. Current from the battery can be used to power other sections of the plant and equipment items in the system 10, including the carbon processing plant 20, on a 24 / 7 basis.

[0097] System 10 includes an air separation unit (ASU) 30 that receives air from air collection system 33, and a water splitting unit (WSU) 32, which may take the form of, for example, an electrolyzer. Both ASU 30 and WSU 32 may be powered by electricity from renewable energy system 14. ASU 30 separates the air into its primary components, primarily oxygen and nitrogen. ASU 30 may be based on any known technology, such as cryogenic air separation, membrane separation, and pressure swing absorption. Oxygen from ASU 30 constitutes or is added to oxygen feed stream 24 for carbon processing plant 20. Nitrogen and other gases produced by ASU 30 may be released to the atmosphere. Alternatively, if desired, the nitrogen may be handled and / or used in a number of different ways, including capture and optional liquefaction as a further saleable product, or distribution as feed stream 27 to and utilization in section 20 of system 10 or plant 20.

[0098] WSU 32 is powered by electricity from renewable energy system 14 and is capable of producing gaseous hydrogen and oxygen. The oxygen produced by WSU 32 is added to oxygen feed stream 24. The hydrogen produced by WSU 32 is supplied to carbon processing plant 20 as hydrogen feed stream 26.

[0099] A water source 34 provides water that forms a water feed stream 28. The feed stream 28 provides water to both the WSU 32 and the carbon processing plant 20.

[0100] Methane source 36 provides the methane for methane feed stream 22. Methane source 36 may hold or supply methane from one or more of a hydrocarbon reservoir, coal seam gas, or biogas, for example, from municipal or other organic waste. If methane source 36 is a biogas source that produces both methane and carbon dioxide, the carbon dioxide can be added to other CO2 feed streams or can itself form the CO2 feed stream for treatment plant 20, as described in more detail in later embodiments.

[0101] In this embodiment, carbon processing plant 20 includes five separate carbon processing units 20a, 20b, 20c, 20d, and 20e. In any specific embodiment of system 10, the carbon processing plant can include different combinations of units 20a, 20b, 20c, 20d, and 20e, depending on the source CS and desired products provided or available. By way of non-limiting example, carbon processing plant 20 in certain embodiments can include (a) units 20a and 20b, (b) units 20a and 20c, (c) units 20a, 20b, and 20c, (d) units 20a, 20d, and 20e, (e) units 20d and 20e, or all of units 20a, 20b, 20c, 20d, and 20e.

[0102] Carbon processing unit 20a is a bioprocess that utilizes methanotrophic bacteria to oxidize methane. Oxygen is also supplied to unit 20a to facilitate methane oxidation. An example of a biologically derived product of this bioprocess, P1, is a single-cell protein that can be used as animal feed, such as, but not limited to, pig feed or fish feed. A by-product of the reaction is carbon dioxide. This carbon dioxide is added to carbon dioxide feed stream 18 for use in other areas of the carbon processing plant, such as, but not limited to, processing unit 20b. This provides an integrated aspect of system 10 and method 12, as the gaseous carbon by-product from one process can be consumed in another process that converts the gaseous carbon by-product into a carbon-neutral / carbon-negative product.

[0103] Carbon processing unit 20b is a bioprocess that utilizes hydrogenotrophic bacteria to consume hydrogen, oxygen, and carbon dioxide present in the water to produce a second, different biologically derived product P2 in the form of a single-cell protein that can be used as animal feed, including swine feed and fish feed.

[0104] The carbon processing unit 20c is a bioprocess that produces photosynthetic cyanobacteria from light, carbon dioxide, and water. High-value products P3 can be extracted from the cyanobacteria in a controlled environment. Examples of high-value products include pharmaceuticals (e.g., anti-cancer drugs), nutritional supplements (e.g., dietary supplements), food additives, and animal feed in the form of single-cell protein.

[0105] Carbon processing units 20d and 20e are used in combination to produce product P4, which are high value chemicals such as ethanol and isopropanol.

[0106] Carbon processing unit 20d is a syngas generation unit. This unit converts carbon dioxide and methane, provided by feed streams 18 and 22, respectively, in the optional presence of oxygen, to produce syngas, a mixture of hydrogen, carbon and its oxides, water, and residual methane. Unit 20d can be a reforming reactor that uses heat produced from energy from energy conversion system 14. A downstream syngas conversion unit 20e converts the syngas into high-value chemicals P4. In one example, unit 20e can be a bioreactor that ferments the syngas, resulting in the production of high-value chemicals such as ethanol and isopropanol. Alternatively, unit 20e can perform a thermochemical process to produce hydrocarbons, such as a Fischer-Tropsch-like process. Additional hydrogen from the hydrogen supply, steam 26, can be provided to unit 20e and used to adjust the ratio of carbon monoxide to hydrogen in the steam feed from unit 20d.

[0107] It should be noted that some of the products or by-products of some of carbon processing units 20a-20e are used by other carbon processing units. For example, carbon monoxide and hydrogen produced by unit 20d are provided as inputs to unit 20e. Carbon dioxide produced by unit 20a can be combined with carbon dioxide from direct air intake system 16 and provided to carbon processing units 20b, 20c, and 20d.

[0108] System 10 and method 12 include a control system having various sensors, gas detectors, flow controllers, and valves to control the flow rate, volume, and pressure of each of carbon dioxide, methane, oxygen, hydrogen, and water feed streams 18, 22, 24, 26, and 28 and to ensure optimal stoichiometric and / or mass balance of the feed streams to each of carbon processing units 20a-20e within carbon processing plant 20. The control system is also provided to monitor and control renewable energy system 14 for the production and storage of energy and distribution of energy to the various plants, systems, and facilities of system 10.

[0109] Figures 3 and 4 are diagrams of an integrated biological carbon processing system 10 and method 12 for converting gaseous carbon compounds to carbon-neutral or carbon-negative products. In describing this embodiment, the same reference numbers used in describing the first embodiment shown in Figures 1 and 2 are used to designate the same systems or processes. A renewable energy system 14 provides the driving force for system 10 and method 12 in the same manner as described in connection with the first embodiment.

[0110] In this embodiment, a single mixed gaseous carbon source CS is provided. The source may take the form of a biogas source. The source CS produces a gaseous feed stream CX as a mixture of gaseous carbon compounds, specifically methane and carbon dioxide. The feed stream CX may also contain other gases, such as nitrogen, hydrogen sulfide, and ammonia. The feed stream CX is fed to a gas pretreatment and separation unit 50. The unit 50 removes non-carbonaceous gases in the feed stream and separates the mixed gaseous carbon compounds into a high-purity methane feed stream 22 and a carbon dioxide feed stream 18.

[0111] In this embodiment, all processing of gaseous carbon compounds occurs biologically within an integrated biological treatment plant 20. Treatment plant 20 includes a biological methane treatment / conversion system 20a and a biological carbon dioxide treatment / conversion system 20b. Treatment systems 20a, 20b use different microorganisms for the treatment of their respective feed gases. A methane feed stream 22 is fed to biological methane treatment / conversion system 20a. System 20a is in the form of a bioreactor with methane-feeding microorganisms, such as methanotrophs, that metabolize methane as a carbon source. Simultaneously, a carbon dioxide feed stream 18 is fed to biological carbon dioxide treatment / conversion system 20b, which consumes carbon dioxide. One example of this is a bioreactor containing hydrogenotrophic bacteria.

[0112] Unconsumed methane and carbon dioxide produced thereby from process / system 20a are recycled back to gas pretreatment and separation unit 50 via conduit 52. In this manner, carbon dioxide produced as a by-product by process 20a is used as a feed input to process 20b.

[0113] System 10 includes first and second harvesting systems HS1 and HS2 and a single-cell protein (SCP) processing system 54, which collectively form a microorganism harvesting and processing system. Microorganisms grown in process 20a are harvested by first harvesting system HS1 as a first single-cell protein source. Microorganisms grown in process 20b are harvested by second harvesting system HS2 as a second product source, also in the form of single-cell proteins. Both harvested single-cell proteins are processed in single-cell protein (SCP) processing system 54, which may include precipitating the proteins in a settling tank to achieve a paste-like consistency and a rotating drum for collecting the paste. SCP processing system 54 also includes a common dryer for drying the paste. Drying occurs while the paste is in the drum. The paste can be dried to a desired moisture content, e.g., 6%-8%, and then converted to single-cell protein powder, which forms the final product P of system 10 and method 12.

[0114] The biological processes 20a and 20b can be supplemented or otherwise enhanced by the addition of feedstocks, including, but not limited to, hydrogen, oxygen, water, ammonia, and nutrients, via a feedstock system 56. The feedstock system 56 includes an air separation unit 30 that produces gaseous oxygen, a water splitting system 32 that produces gaseous hydrogen and oxygen, and a nutrient system 58. An air collection system 33 supplies air to the air separation system 30. A water source 34 (which may be, for example, a city water supply) supplies water to the water splitting system 32. The nutrient system 58 can provide macronutrients and / or micronutrients. Micronutrients can include, but are not limited to, cobalt, manganese, iron, zinc, chlorine, boron, and vitamins. Macronutrients can include, but are not limited to, phosphorus, potassium, and nitrogen. Each of the systems in the feedstock system 56 is powered by a renewable energy system 14.

[0115] Auxiliary systems 62 are provided to assist in maintaining the operation of the integrated biological treatment plant 20. The auxiliary systems 62 may include a cooling system 64, a cleaning-in-place system 66, and a wastewater treatment system 68. The cooling system 64 operates to remove heat generated by the metabolic processes 20a and 20b. The cooling system 64 maintains temperatures within the reactors used in the processes 20a and 20b within the optimal activation range for the respective mesophilic bacteria. In one example, the cooling system may be in the form of a water jacket surrounding each reactor. The cooling system may provide different operating temperatures for each reactor for the processes 20a and 20b. Temperature control may be provided by an electrically controlled temperature regulator powered by the renewable energy system 14.

[0116] The cleaning-in-place system 66 is used to periodically or on-demand clean the reactors used to carry out the processes 20a, 20b. It may deliver, for example, water and / or steam and / or various chemicals to clean and sanitize the bioreactors, including removing biofilm or other residues. A wastewater treatment system may treat water from one or more of the cleaning-in-place system 66, the SCP treatment system 54, and the plant 20.

[0117] The size of the bioreactor used in processes 20a, 20b is determined based on the gas supply and the amount of carbon dioxide recycled from process 20a to unit 50 via conduit 52.

[0118] 4, provided for illustrative purposes only, is a mass flow diagram for system 10, method 12 for a single mixed biogas source CS producing 10 tons per day (tpd) of mixed methane and carbon dioxide in a weight ratio of approximately 38:62. 3.8 tpd of methane and 6.2 tpd of carbon dioxide are fed from the gas pretreatment and separation unit to the respective reactors carrying out processes 20a and 20b. In addition, process 20a produces approximately 4.1 tpd of CO2 as a by-product, which is provided to process 20b as an additional feedstock.

[0119] Air and water are supplied at approximately 15.2 tpd and 16.1 tpd, respectively, to produce the mass flows of oxygen and hydrogen needed to support the processing of methane and carbon dioxide. Methane processing / conversion system 20a receives 3.5 tpd of oxygen from air separation unit 30 and 7.7 tpd of oxygen from water splitting unit 32. Water splitting unit 32 also supplies 6.6 tpd of oxygen and 1.8 tpd of hydrogen to carbon dioxide processing / conversion system 20b. These mass flows result in the production of approximately 2.3 tpd of single-cell protein by system 20a and approximately 5.8 tpd of single-cell protein by system 20b. Nitrogen and other gases produced by the air separation units are output at a rate of approximately 11.7 tpd and processed by processing unit 70. This may include, for example, capturing the nitrogen as a gas or liquefying the nitrogen, which can then be sold to a third party.

[0120] Methanotrophic bacteria, cyanobacteria, and hydrogenotrophic bacteria can all be considered mesophilic bacteria that function optimally in a temperature range of approximately 15°-45° C. The process and material flows in embodiments of system 10 and method 12 can be carried out at atmospheric pressure. The doubling rate of the bacteria under these conditions can vary between 2-8 hours.

[0121] The system and method described with reference to Figures 3 and 4 is well suited to livestock farming, e.g., pig farming, as a closed-loop biogas processing system capable of producing animal feed material, i.e., single-cell protein, derived from animal waste. This is a carbon-negative process because it consumes the greenhouse gases methane and carbon dioxide that would otherwise be released by the decomposition of waste and uses renewable energy as its power source.

[0122] As will become apparent from the above description, the embodiment shown in Figures 3 and 4 is a substantial subset of the system shown in Figures 1 and 2 for producing single-cell proteins using bioprocesses 20a, 20b, and / or 20c, renewable energy system 14, and air and water inputs that feed air separation unit 30 and water splitting unit 32, respectively. System 10 of Figures 3 and 4 can be augmented or modified by the addition of carbon processing units 20d and 20e, and / or additional gaseous carbon compound sources.

[0123] While exemplary embodiments have been presented in the foregoing detailed description, it should be recognized that numerous variations exist. For example, in system 10 shown and described in connection with Figures 3 and 4, the bioprocess used to consume carbon dioxide is carried out by hydrogenotrophic bacteria. However, alternatively, or indeed additionally, the bioprocess can include the previously described process 20c, which utilizes photosynthetic cyanobacteria to consume gaseous carbon dioxide to produce high-value products, such as pharmaceuticals (e.g., anti-cancer drugs), nutritional supplements (e.g., dietary supplements), and food additives, in the presence of water. In another variation, in addition to or as an alternative to WSU 32, system 10 can include a methane pyrolysis unit for the purpose of hydrogen gas production. Similarly, the gaseous carbon dioxide feed stream 18 can utilize or otherwise be supplied with gaseous carbon compounds from one or more of several sources, including, but not limited to, DAC 16; an acid gas removal unit in a liquefied natural gas processing plant; fossil fuel production, processing, or combustion; and by-products or waste products of industrial plants, such as, but not limited to, cement manufacturing plants and ammonia production plants. Additionally, embodiments of the system 10 and method 12 can be provided as add-ons to any existing industrial production plant that produces gaseous carbon compounds as by-products or waste products to produce additional valuable products. When used in this manner, they can also expand the capacity of a renewable energy system to power the industrial production plant, thereby further helping to reduce the plant's carbon footprint. In another variation of the system described with reference to Figures 3 and 4, the microbial harvesting and processing system can include separate processing systems 54 for each of the harvesting systems HS1 and HS2, rather than a common processing system 54. It should also be recognized that the exemplary implementations of the systems and methods are merely examples and are not intended to limit the scope, applicability, or configuration of the present disclosure in any way.Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing exemplary embodiments of the disclosed systems and methods.

[0124] In the following claims and the preceding description, unless the context requires otherwise due to express language or necessary implications, the terms "comprises" and variations thereof, such as "comprises" or "comprised," are used in an open sense, in other words, to specify the presence of the recited features in various embodiments of the systems and methods disclosed herein, but do not preclude the presence or addition of further features.

Claims

[Claim 1] 1. An integrated system for converting gaseous carbon compounds to carbon-neutral or carbon-negative products, comprising: one or more units that produce each of the reactants; one or more sources of carbon dioxide and methane; a biological methane treatment system comprising methane-metabolizing microorganisms and supplied with methane from said one or more sources and one or more of said reactants, wherein the biological methane treatment system propagates the methane-metabolizing microorganisms and produces carbon dioxide as a by-product; a biological carbon dioxide processing system containing carbon dioxide metabolizing microorganisms and supplied with carbon dioxide from one or more of the one or more sources, the by-products of carbon dioxide, and the reactants, wherein the biological carbon dioxide processing system propagates the carbon dioxide metabolizing microorganisms; a microorganism harvesting and processing system that harvests the methane-metabolizing microorganisms propagated by the biological methane processing system, harvests the carbon dioxide-metabolizing microorganisms propagated by the biological carbon dioxide processing system, and produces single-cell proteins; a control system that controls the flow of the carbon dioxide, methane, and reactants to the biological methane treatment system and the biological carbon dioxide treatment system to provide mass-balanced amounts of the carbon dioxide, methane, and reactants for processing in each of the biological methane treatment system and the biological carbon dioxide treatment system; An integrated system that encompasses all of the above.

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