Integration of adsorption device and gas fermentation

Abstract

An integrated temperature swing adsorption (TSA) process and gas fermentation process and apparatus are disclosed. A heated off-gas stream from the gas fermentation process is used to heat and regenerate the sorbent in the TSA unit. A portion of the treated feedstock from the TSA unit is used to cool the regenerated sorbent. Integration of a tail gas stream from a gas fermentation zone for regenerating the sorbent in the TSA eliminates the need for inert gas regenerant, and the use of TSA treated gaseous feedstock to cool the regenerated sorbent allows maximized recovery and use of available gaseous feedstock. Alternatively, when a pressure swing adsorption (PSA) process is also employed, a purge stream from the PSA may be used as a regenerant in the TSA process.

Description

Technical Field

[0001] The present disclosure relates to a method and apparatus for integrating temperature swing adsorption and gas fermentation. A substrate for gas fermentation passes through an adsorption device to remove impurities to ensure safe gas fermentation. Background Art

[0002] Carbon dioxide (CO2) accounts for approximately 76% of global greenhouse gas emissions caused by human activities, with methane (16%), nitrous oxide (6%), and fluorinated gases (2%) accounting for the remainder (United States Environmental Protection Agency). Most CO2 comes from burning fossil fuels to produce energy, but industrial and forestry practices also emit CO2 into the atmosphere. Reducing greenhouse gas emissions, particularly CO2, is crucial for halting the process of global warming and the consequent climate and weather changes.

[0003] It has long been recognized that catalytic processes, such as the Fischer-Tropsch process, can be used to convert gases containing carbon dioxide (CO2), carbon monoxide (CO), and / or hydrogen (H2), such as industrial waste gas or syngas or mixtures thereof, into various chemicals, such as ethanol, acetone, and isopropyl alcohol. Syngas can also be converted into various chemicals through the Monsanto process, with the conversion to methanol as the first step. Both the Fischer-Tropsch and methanol synthesis units are optimized for very high capacities. They require a well-defined feed gas composition and syngas feed with low impurities to avoid poisoning the catalyst. The Fischer-Tropsch process requires complex and expensive purification equipment to produce high-purity industrial chemicals. Recently, gas fermentation has emerged as an alternative platform for the biological fixation of such gases. It has been demonstrated that C1-fixing microorganisms convert gases containing CO 2、 CO and / or H2, such as industrial waste gas or syngas or mixtures thereof, into products such as ethanol and 2,3-butanediol.

[0004] Gas fermentation has emerged as an alternative platform for biological capture and conversion in gases containing single-carbon compounds such as carbon monoxide (CO), carbon dioxide (CO2), and / or methane (CH4). Specifically, C1-fixing microorganisms act as biocatalysts to convert C1-carbon gaseous substrates into valuable fermentation products such as ethanol or other C1-C4 alcohols.

[0005] Temperature swing adsorption (TSA) can be used to remove contaminants from a gaseous feedstock. When a TSA bed becomes unable to effectively remove the desired impurities to the desired concentration due to the adsorbent approaching its adsorption capacity limit, this is referred to as "saturation" and the adsorbent can be regenerated. The adsorbent bed contains at least one adsorbent selected to remove the target impurities. Additional adsorbents can be added to the adsorbent bed to target multiple impurities. Adsorbent regeneration is achieved by passing a heated gas through the adsorbent bed to transfer heat from the regeneration gas to the adsorbent. As the adsorbent temperature increases, the impurities are desorbed from the adsorbent since the saturation capacity of the adsorbent decreases with increasing temperature. The regeneration gas flow rate is sufficient to ensure thorough mixing and to ensure that the regeneration gas is not saturated with the desorbed impurities. Typically, an inert gas (such as nitrogen) is used as the regeneration gas. However, the production of inert gas involves expensive equipment, thus increasing the overall cost. Additionally, the inert gas laden with impurities must be further processed before being released to the atmosphere or reused. A typical treatment method is thermal oxidation at high temperature. Given the inert nature of the regeneration gas, a large amount of energy is required to heat the inert gas laden with impurities to the required thermal oxidation temperature. Alternatively, a portion of the untreated gaseous feedstock can be heated and used as the regeneration gas. However, this reduces the amount of gaseous substrate available for fermentation. Therefore, there is a need for a method and apparatus for regenerating a saturated adsorbent bed in addition to using an inert gas for regeneration, while also preserving the gaseous feedstock for the process and not sacrificing regeneration. SUMMARY OF THE INVENTION

[0006] In one aspect of the present disclosure, a method for integrating a TSA process and a gas fermentation process comprises (a) providing a TSA process and a gas fermentation process, the TSA process comprising at least a first adsorption bed and a second adsorption bed, the first adsorption bed comprising an adsorbent, the second adsorption bed comprising spent or saturated adsorbent, the gas fermentation process comprising a bioreactor comprising at least one C1-fixing microorganism in a nutrient solution; (b) passing a gaseous feedstock comprising CO, CO2, H2, CH4, or any combination thereof and at least one contaminant (or impurity) to the first adsorption bed operating at an adsorption temperature, adsorbing the contaminant on the adsorbent, and producing a contaminant-depleted treated gaseous feedstock; (c) passing at least a portion of the treated gaseous feedstock to the gas fermentation process to produce a gas fermentation product stream comprising a gas fermentation product and a tail gas stream; (d) first passing at least a portion of the tail gas stream to a heater to produce a heated tail gas stream, the heated tail gas stream passing from the gas fermentation process to the second adsorption bed at a regeneration temperature and passing through the spent adsorbent to desorb the adsorbed contaminant and provide a heated regenerated adsorbent, wherein the regeneration temperature is greater than the adsorption temperature; (e) then passing at least a portion of the treated gaseous feedstock from the first adsorption bed to the second adsorption bed and passing through the regenerated adsorbent to cool the heated regenerated adsorbent to the adsorption temperature and provide an effluent stream from the regeneration bed; and (f) combining the effluent stream from the second adsorption bed with the treated gaseous feedstock from the first adsorption bed, or passing the effluent stream of the treated gaseous feedstock to the gas fermentation process, or both. Generally, the tail gas is the gas and vapor that can be released from the process to the atmosphere after the reaction and treatment occur. The process steps (a) to (f) are periodically repeated. In another embodiment, the method further comprises a third adsorption bed in a standby mode, the third adsorption bed comprising a regenerated adsorbent. In another embodiment, the method further comprises more than three adsorption beds in a standby mode, the more than three adsorption beds comprising regenerated adsorbents. In yet another embodiment, the method further comprises passing the heated tail gas stream from the gas fermentation process through a scrubber to remove and recover the gas fermentation product from the tail gas stream before passing it to the first adsorption bed.

[0007] The method further comprises (a) adjusting the operating pressure of the first adsorption bed to correspond to the pressure of the gaseous feedstock, and / or (b) adjusting the operating pressure of the second adsorption bed to correspond to the pressure of the heated tail gas stream from the gas fermentation process. The gas fermentation process can operate at a lower pressure relative to the adsorption pressure or at a higher pressure relative to the adsorption pressure.

[0008] In another aspect of the present disclosure, a method for integrating a TSA process, a pressure swing adsorption (PSA) process, and a gas fermentation process comprises (a) providing a TSA process, a pressure swing adsorption process, and a gas fermentation process, the TSA process comprising at least a first TSA adsorption bed and a second TSA adsorption bed, the first TSA adsorption bed comprising a TSA adsorbent, the second TSA adsorption bed comprising a TSA spent adsorbent, the pressure swing adsorption process comprising at least a first PSA adsorption bed and a second PSA adsorption bed, the first PSA adsorption bed comprising a PSA adsorbent, the second PSA adsorption bed comprising a PSA spent adsorbent, the gas fermentation process comprising a bioreactor, the bioreactor comprising at least one C1-fixing microorganism in a nutrient solution; (b) transferring a gaseous feedstock comprising CO, CO2, H2, CH4, or any combination thereof and at least one contaminant to the first TSA adsorption bed operating at an adsorption temperature, adsorbing the contaminant on the TSA adsorbent, and producing a TSA-treated gaseous feedstock depleted of the contaminant; (c) transferring at least a portion of the treated gaseous feedstock to the first PSA adsorption bed operating at an adsorption pressure, adsorbing CO2 on the PSA adsorbent, and producing a PSA-treated gaseous feedstock depleted of CO2; (d) transferring the PSA-treated gaseous feedstock to the gas fermentation process to produce a gas fermentation product stream comprising a gas fermentation product; (e) regenerating the first PSA bed by reducing the operating pressure to below the adsorption pressure, thereby producing a PSA purge gas stream rich in CO2; (f) then transferring at least a portion of the PSA purge gas stream from the second PSA adsorption bed to the second TSA adsorption bed at a desorption temperature to desorb the adsorbed contaminant and provide a TSA purge gas comprising the contaminant and CO2. In another embodiment, the gaseous feedstock comprises methane, hydrogen sulfide, and / or other light hydrocarbons, and the PSA bed adsorbs the methane or other light hydrocarbons (C1-C 13 ) or hydrogen sulfide. In one embodiment, a compressor is used to increase the pressure of the PSA purge gas to a pressure high enough to overcome the pressure drop across the second TSA bed and associated equipment.

[0009] In another aspect of the present disclosure, a method for integrating a temperature swing adsorption process, a pressure swing adsorption process, and a gas fermentation process includes providing a temperature swing adsorption process, a pressure swing adsorption process, and a gas fermentation process. The temperature swing adsorption process includes at least a first TSA adsorption bed and a second TSA adsorption bed. The first TSA adsorption bed includes a TSA adsorbent, and the second TSA adsorption bed includes a TSA spent adsorbent. The pressure swing adsorption process includes at least a first PSA adsorption bed and a second PSA adsorption bed. The first PSA adsorption bed includes a PSA adsorbent, and the second PSA adsorption bed includes a PSA spent adsorbent. The gas fermentation process includes a bioreactor that includes at least one C1-fixing microorganism in a nutrient solution. A gaseous feedstock containing CO, CO2, H2, CH4, or any combination thereof and at least one contaminant is transferred to the first TSA adsorption bed operating at an adsorption temperature. The contaminant is adsorbed on the TSA adsorbent, and a TSA-treated gaseous feedstock depleted of the contaminant is produced. At least a portion of the treated gaseous feedstock is transferred to the gas fermentation process to produce a fermentation off-gas and a gas fermentation product stream containing a gas fermentation product. At least a portion of the fermentation off-gas is transferred to the first PSA adsorption bed operating at an adsorption pressure. CO2 is adsorbed on the PSA adsorbent, and a PSA-treated fermentation off-gas depleted of CO2 and a PSA purge gas are produced. At least a portion of the PSA purge gas is transferred from the first PSA adsorption bed to the second TSA adsorption bed at a desorption temperature to desorb the adsorbed contaminant and provide a TSA purge gas containing the contaminant and CO2.

[0010] In another aspect of the present disclosure, an integrated TSA and gas fermentation apparatus comprises (i) a gaseous feedstock source in fluid communication with a first adsorption bed containing an adsorbent, the first adsorption bed further comprising a treated gaseous feedstock outlet; (ii) a second adsorption bed containing spent adsorbent and having an effluent outlet, wherein the treated gaseous feedstock outlet of the first adsorption bed is further in fluid communication with the second adsorption bed; and (iii) a bioreactor of the gas fermentation apparatus in fluid communication with the treated gaseous feedstock outlet of the first adsorption bed and the effluent outlet of the second adsorption bed, the bioreactor comprising a tail gas outlet and a product stream outlet, the tail gas outlet being in fluid communication with the second adsorption bed. The apparatus further comprises a third adsorption bed in a standby mode, the third adsorption bed containing regenerated adsorbent, the third adsorption bed being in fluid communication with the bioreactor. In one embodiment, a scrubber is in fluid communication with the tail gas outlet of the bioreactor, the scrubber being further in fluid communication with the second adsorption bed. In yet another embodiment, the apparatus further comprises a regeneration heater in fluid communication with the tail gas outlet of the bioreactor.

[0011] In yet another aspect of the present disclosure, an integrated TSA, pressure swing adsorption and gas fermentation apparatus comprises: (i) a gaseous feedstock source unit in fluid communication with a first TSA adsorption bed containing an adsorbent, the first TSA adsorption bed further comprising a treated gaseous feedstock outlet; (ii) a first PSA adsorption bed containing PSA adsorbent, the first PSA bed being in fluid communication with the treated gaseous feedstock outlet of the first TSA adsorption bed, wherein the first PSA adsorption bed is further in fluid communication with the bioreactor; and (iii) a second PSA adsorption bed containing PSA spent adsorbent, in fluid communication with the treated gaseous feedstock outlet of the first TSA adsorption bed, wherein the second PSA adsorption bed is further in fluid communication with a second TSA adsorption bed containing TSA spent adsorbent. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings are simplified by deleting a large number of devices commonly used in processes of this nature, such as internals of vessels, temperature and pressure control devices, flow control valves, compressors, etc., which are not specifically required to illustrate the performance of the present invention. In addition, the description of the processes of the present invention in the embodiments of a particular drawing is not intended to limit the present disclosure to the specific embodiments. Some embodiments may be described with reference to the method configurations shown in the figures, which relate to both the apparatus and the methods for carrying out the present disclosure. Any reference to a method step includes a reference to the apparatus unit or apparatus suitable for carrying out the step, and vice versa.

[0013] Figure 1A and 1B is a schematic flow chart showing three TSA beds according to an embodiment of the present disclosure.

[0014] Figure 2A and 2B is a schematic flow chart showing two TSA beds and two PSA beds (PSA) according to an embodiment of the present disclosure. Detailed Description

[0015] In an integrated TSA and gas fermentation apparatus, almost complete or complete recovery of the treated gaseous feedstock and elimination of the need for an inert regeneration gas are benefits achieved by the methods and apparatus of the present disclosure. For ease of understanding, the present disclosure is explained in terms of a TSA swing bed apparatus with two or more TSA beds. A first TSA bed is online and operating, while a second TSA bed is being regenerated or has been regenerated and is ready to provide service. At the point in time when the first TSA bed approaches its adsorption capacity or becomes saturated, the first TSA bed "switches" from service to regeneration, and the second TSA bed "switches" to online service. The process continues in the use of at least one TSA bed while the other is in a regenerating or ready-to-provide-service state. In the present disclosure, a saturated TSA bed is regenerated using the "heated" tail gas stream from the gas fermentation process and then cooled using the treated gaseous feedstock from another TSA bed of the TSA swing bed apparatus. On the other hand, a stream from the PSA bed is used to regenerate the TSA bed. Thus, the regeneration of the TSA bed does not require an inert regeneration gas, which is a common practice, and thus eliminates the cost of obtaining or generating an inert regeneration gas. Further, the treated gaseous feedstock is almost completely recovered even when used during the regeneration process.

[0016] The gas fermentation zone of the apparatus comprises at least one bioreactor, which comprises at least one C1-fixing microorganism. The term "bioreactor" includes a fermentation device consisting of one or more vessels and / or tower or pipeline arrangements, which includes a continuously stirred tank reactor, a fixed cell reactor, a trickle bed reactor, a bubble column, an airlift fermenter, a static mixer, a recycle loop reactor, a membrane reactor such as a hollow fiber membrane bioreactor, or other vessels or other devices suitable for gas-liquid contact. The bioreactor may also comprise a device of multiple reactors (stages) in parallel or in series. For example, the bioreactor may comprise a first growth reactor for culturing microorganisms and a second fermentation reactor, and the output from the growth reactor may be fed to the second fermentation reactor, and the second fermentation reactor produces most of the fermentation products. In some embodiments, a plurality of bioreactors in the bioreactor device are placed on top of each other to form a stack. The stack of bioreactors increases the throughput of the bioreactor device without significantly increasing the land area requirements. In some embodiments, the bioreactor comprises a downflow or upflow bioreactor having a mechanism for forming smaller substrate bubbles in a liquid medium and thus substantially increasing the gas-liquid mass transfer rate without increasing energy consumption.

[0017] A "C1-fixing microorganism" is a microorganism that produces one or more products from a C1 carbon source or substrate. A "C1 carbon source or substrate" refers to a single carbon molecule that serves as a partial or sole carbon source for the microorganism. For example, the C1 carbon source or substrate may comprise one or more of the following: CO, CO2, CH4, CH3OH, or CH2O2. In one embodiment, the C1 carbon source or substrate comprises one or both of CO and CO2. In addition to C1 compounds, the gaseous substrate containing C1 may further comprise other non-carbon components such as H2, N2, and / or electrons.

[0018] The term "feedstock" when used in the context of a feed stream flowing into a gas fermentation bioreactor (i.e., a gas fermenter) or a "gas fermentation feedstock" is understood to encompass any material (solid, liquid, or gas) or feed stream that can provide a substrate to the gas fermenter or bioreactor either directly or after feedstock processing.

[0019] Typically, the gaseous fermentation feedstocks include, but are not limited to, industrial waste gas, syngas, biogas, landfill gas, direct air capture gas, or any combination thereof. A portion of the substrate and / or C1 carbon source can be a gas obtained as a by-product of an industrial process or a gas from another source, such as internal combustion engine exhaust, biogas, landfill gas, direct air capture, combustion, or gas from electrolysis. However, a portion of the substrate and / or C1 carbon source is syngas produced by pyrolysis, torrefaction, or gasification. In other words, the carbon in solid or liquid materials can be recycled by pyrolysis, torrefaction, or gasification to produce syngas that is used as a substrate and / or C1 carbon source in gaseous fermentation. A portion of the substrate and / or C1 carbon source can be natural gas, carbon dioxide from conventional and unconventional gas production, and / or methane-containing gas. The gaseous fermentation process is flexible and can use any of these substrates and / or carbon sources.

[0020] In certain embodiments, the industrial processes for the optional portion of the substrate and / or C1 carbon source include, but are not limited to, ferrous metal product manufacturing such as steelmaking, non-ferrous metal product manufacturing, petroleum refining, power production, carbon black production, paper and pulp manufacturing, ammonia production, methanol production, coke manufacturing, petrochemical production, carbohydrate fermentation, cement manufacturing, aerobic digestion, anaerobic digestion, catalytic processes, natural gas extraction, cellulose fermentation, oil extraction, industrial processing of geological reservoirs, processing of fossil resources such as natural gas, coal, and petroleum, landfill operations, silicon carbide production, or any combination thereof. Examples of specific processing steps within the industrial methods include catalyst regeneration, fluid catalytic cracking, and catalyst regeneration. Air separation and direct air capture are other suitable industrial processes. Specific examples in steel and ferroalloy manufacturing include blast furnace gas, basic oxygen furnace gas, coke oven gas, direct reduction of top gas from an iron furnace, and residual gas from iron smelting. Other general examples include flue gas from combustion boilers and combustion heaters such as natural gas, oil, or coal-fired boilers or heaters, and gas turbine exhaust. Another example is the combustion of compounds, such as at oil and gas production sites. In these embodiments, any known method can be used to capture the substrate and / or C1 carbon source from the industrial process and then vent it to the atmosphere.

[0021] The substrate and / or C1 carbon source is a synthesis gas known as syngas, which can be obtained from reforming, partial oxidation, plasma or gasification processes. Examples of gasification processes include gasification of coal, gasification of refinery residues, gasification of petroleum coke, gasification of biomass, gasification of lignocellulosic materials, gasification of wood, gasification of black liquor, gasification of municipal solid waste, gasification of municipal liquid waste, gasification of industrial solid waste, gasification of industrial liquid waste, gasification of refuse-derived fuel, gasification of sewage, gasification of sewage sludge, gasification of sludge from wastewater treatment, gasification of landfill gas, gasification of biogas, such as when biogas is added to enhance the gasification of another material, gasification of rubber-containing materials, including partial and whole tires. Examples of reforming processes include steam methane reforming, steam naphtha reforming, natural gas reforming, biogas reforming, landfill gas reforming, coke oven gas reforming, pyrolysis off-gas reforming, ethylene-producing off-gas reforming, naphtha reforming and dry methane reforming. Examples of partial oxidation processes include thermal and catalytic partial oxidation processes, catalytic partial oxidation of natural gas, partial oxidation of hydrocarbons, partial oxidation of biogas, partial oxidation of landfill gas or partial oxidation of pyrolysis off-gas. Examples of municipal solid waste include tires, plastics, refuse-derived fuel and fibers in items such as shoes, clothing and textiles. Municipal solid waste may be of the simple landfill type of waste and may or may not be sorted. Tires including those with the ends filed down can be a feedstock. Examples of biomass can include lignocellulosic materials and microbial biomass. Lignocellulosic materials can include agricultural by-products, forestry by-products and some industrial by-products. Whole tires can be pyrolyzed to form syngas.

[0022] Biomass can be produced as a by - product of “Nature - based Solutions” (NBS), and thus Nature - based Solutions can provide feedstocks for gas fermentation processes. The European Commission refers to Nature - based Solutions as solutions inspired and supported by nature, which are cost - effective while providing environmental, social and economic benefits and contributing to enhanced resilience. Such solutions introduce more and more diverse natural and natural features and processes into cities, landscapes and seascapes through context - specific, resource - efficient and systemic interventions. Nature - based Solutions must be beneficial to biodiversity and support the provision of a range of ecosystem services. By using NBS, healthy, resilient and diverse ecosystems (whether natural, managed or newly created) can provide solutions for the benefit of both society and overall biodiversity. Examples of Nature - based Solutions include nature - based climate solutions (conserving, restoring and improving land management, increasing carbon storage or avoiding greenhouse gas emissions in landscapes and wetlands around the world), halting biodiversity loss, socio - economic impact efforts, habitat restoration and health and well - being efforts in relation to air and water. Biomass produced through Nature - based Solutions can be used as a feedstock for gas fermentation processes.

[0023] Part of the substrate and / or C1 carbon source can be a methane - containing gas stream. Such methane - containing gas can be emitted from fossil methane, such as obtained during fracking, wastewater treatment, livestock, agriculture and municipal solid waste landfilling. It is also envisaged that methane can be burned to generate electricity or heat, and the C1 by - products can be used as a substrate or carbon source. The substrate and / or C1 carbon source can be a natural - gas - containing gas stream.

[0024] Synthesis gas substrates typically contain a large proportion of CO, such as at least about 15 vol% to about 75 vol% of CO, about 20 vol% to about 70 vol% of CO, about 20 vol% to about 65 vol% of CO, about 20 vol% to about 60 vol% of CO, and about 20 vol% to about 55 vol% of CO. In some embodiments, the synthesis gas substrate comprises about 25 vol% of CO, or about 30 vol% of CO, or about 35 vol% of CO, or about 40 vol% of CO, or about 45 vol% of CO, or about 50 vol% of CO, or about 55 vol% of CO or about 60 vol% of CO. In other embodiments, synthesis gas substrates typically contain a large proportion of CO2, such as at least about 15 vol% to about 75 vol% of CO2, about 20 vol% to about 70 vol% of CO2, about 20 vol% to about 65 vol% of CO2, about 20 vol% to about 60 vol% of CO2, and about 20 vol% to about 55 vol% of CO2. In some embodiments, the synthesis gas substrate comprises about 25 vol% of CO2, or about 30 vol% of CO2, or about 35 vol% of CO2, or about 40 vol% of CO2, or about 45 vol% of CO2, or about 50 vol% of CO2, or about 55 vol% of CO or about 60 vol% of CO2.

[0025] The C1 immobilized microorganisms can be selected from the group consisting of Clostridium, Moorella, Pyrococcus, Eubacterium, Desulfobacterium, Carboxydothermus, Acetogenium, Acetobacterium, Acetoanaerobium, Butyribaceterium, Peptostreptococcus, and mixtures thereof. The microorganisms in the bioreactor can be modified microorganisms derived from naturally occurring or parental microorganisms. A "parental microorganism" is a microorganism from which another microorganism can be derived. Both the parental microorganism and the derived microorganism are suitable microorganisms. The parental microorganism can be a naturally occurring microorganism (i.e., a wild-type microorganism) or a microorganism that has been previously modified (i.e., an optimized, mutated, or recombinant microorganism). Suitable microorganisms can be modified to express or overexpress one or more enzymes not expressed or overexpressed in the parental microorganism. Similarly, the microorganisms of the present disclosure can be modified to contain one or more genes not present in the parental microorganism. The microorganisms can also be modified to not express or express a lower amount of one or more enzymes expressed in the parental microorganism.According to one embodiment, the microorganism is selected from or derived from the following: Acetobacterium woodii, Alkalibaculum bacchii, Blautia producta, Butyribacterium methylotrophicum, Clostridium aceticum, Clostridium autoethanogenum, Clostridium carboxidivorans, Clostridium coskatii, Clostridium drakei, Clostridium formicoaceticum, Clostridium ljungdahlii, Clostridium magnum, Clostridium ragsdalei, Clostridium scatologenes, Eubacterium limosum, Moorella thermautotrophica, Moorella thermoacetica, Oxobacter pfennigii, Sporomusa ovata, Sporomusa silvacetica, Sporomusa sphaeroides, Cupriavidus necator, Thermoanaerobacter kivui, or any combination thereof. In one embodiment, the microorganism is selected from or derived from Clostridium autoethanogenum, Clostridium ljungdahlii, or Clostridium ragsdalei. In one embodiment, the parental microorganism is Clostridium autoethanogenum, which was deposited on June 7, 2010, at Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH (DSMZ), Inhoffenstraße 7B, D-38124 Braunschweig, Germany, under the terms of the Budapest Treaty and given the accession number DSM 23693. This strain is described in International Patent Application No. PCT / NZ2011 / 000144, published as WO 2012 / 015317.

[0026] The microorganisms of the present disclosure can be cultured with gaseous substrates to produce one or more products. For example, in addition to 2-phenylethanol (WO 2021 / 188190, US2021 / 0292732) and ethylene, the microorganisms can produce or can be engineered to produce ethanol (WO 2007 / 117157, US 7,972,824), acetate (WO 2007 / 117157, US 7,972,824), 1-butanol (WO 2008 / 115080, US 8,293,509, WO 2012 / 053905, US 9,359,611 and WO 2017 / 066498, US 9,738,875), butyrate (WO 2008 / 115080, US 8,293,509), 2,3-butanediol (WO 2009 / 151342, US 8,658,408 and WO 2016 / 094334, US 10,590,406), lactate (WO 2011 / 112103, US8,900,836), butene (WO 2012 / 024522, US2012 / 045807), butadiene (WO 2012 / 024522, US 2012 / 045807), methyl ethyl ketone (2-butanone) (WO 2012 / 024522, US2012 / 045807 and WO 2013 / 185123, US 9,890,384), ethanol that is then converted to ethylene (WO 2012 / 026833, US2013 / 157,322), acetone (WO 2012 / 115527, US 9,410,130), isopropanol (WO 2012 / 115527, US 9,410,130), lipids (WO 2013 / 036147, US 9,068,202), 3-hydroxypropionate (3-HP) (WO 2013 / 180581, US 9,994,878), terpenes, including isoprene (WO 2013 / 180584, US10,913,958), fatty acids (WO 2013 / 191567, US 9,347,076), 2-butanol (WO2013 / 185123, US 9,890,384), 1,2-propanediol (WO 2014 / 036152, US 9,284,564), 1-propanol (WO2014 / 0369152, US 9,284,564), 1-hexanol (WO 2017 / 066498, US 9,738,875), 1-octanol (WO 2017 / 066498, US 9,738,875), products derived from chorismate (WO 2016 / 191625, US10,174,303), 3-hydroxybutyric acid (WO 2017 / 066498, US 9,738,875), 1,3-butanediol (WO 2017 / 066498, US 9,738,875), 2-hydroxyisobutyrate or 2-hydroxyisobutyric acid (WO 2017 / 066498, US 9,738,875), isobutene (WO 2017 / 066498, US 9,738,875), adipic acid (WO 2017 / 066498, US 9,738,875), 1,3-hexanediol (WO 2017 / 066498, US 9,738,875), 3-methyl-2-butanol (WO 2017 / 066498, US 9,738,875), 2-buten-1-ol (WO 2017 / 066498, US 9,738,875), isovalerate (WO 2017 / 066498, US 9,738,875), isopentanol (WO 2017 / 066498, US 9,738,875) and / or monoethylene glycol (WO 2019 / 126400, US11,555,209).

[0027] In certain embodiments, the microbial biomass itself can be considered a product. These products can be further converted to produce at least one component of diesel, jet fuel, sustainable aviation fuel (SAF), and / or gasoline. In certain embodiments, ethylene can be catalytically converted to another product, article, or any combination thereof. Additionally, the microbial biomass can be further processed by any method or combination of methods known in the art to produce single cell protein (SCP). The fermentation broth effluent from the bioreactor contains the products produced and the culture medium present in the bioreactor.

[0028] The bioreactor for the gas fermentation process is operated under suitable conditions to produce a product. The specific reaction conditions will depend in part on the specific microorganism used and the target product. However, generally, it is preferred to operate the fermentation at a pressure above atmospheric pressure and at a temperature suitable for the use of the specific microorganism.

[0029] Any method or combination of methods known in the art can be used to separate or purify the target product from the fermentation broth effluent, said methods including, for example, fractional distillation, evaporation, pervaporation, stripping, phase separation, and extractive fermentation (including, for example, liquid-liquid extraction). In certain embodiments, the target product is recovered from the fermentation broth by continuously removing a portion of the fermentation broth from the bioreactor, separating the microbial biomass from the fermentation broth (such as by filtration, including membrane removal), and recovering one or more target products from the permeate. Alcohols and / or acetone can be recovered, for example, by distillation. Acids can be recovered, for example, by adsorption onto activated carbon. The separated microbial biomass, such as the microbial biomass in the retentate, can be returned to the bioreactor. A portion of the cell-free permeate of the microorganisms remaining after the target product has been removed can be returned to the bioreactor to recycle the culture medium. Additional nutrients can be added to the recycled cell-free permeate to replenish the culture medium before recycling to the bioreactor. The product and the microbial biomass can be recovered in one operation using vacuum distillation.

[0030] The substrates of the gas fermentation process are typically treated to remove fermentation inhibitory components before introduction into the bioreactor. A TSA unit can be used to adsorb selective contaminants in the gas feedstock onto an adsorbent at an adsorption temperature. After the adsorbent is saturated, the adsorbed contaminants are desorbed from the adsorbent at a desorption temperature, and the TSA bed is thereby regenerated and can be used again. Suitable adsorbents used in the TSA bed include, but are not limited to, zeolite molecular sieves, activated carbon, silica gel, activated alumina, or any combination thereof. Typical fermentation inhibitors removed by adsorption onto the TSA bed can include, but are not limited to, hydrocarbons, oxygenates, sulfur compounds, nitrogen compounds, or any combination thereof. If present, lighter tars with lower boiling points, such as benzene, toluene, ethylbenzene, and xylene (BTEX), can also be removed from the feedstock.

[0031] Referring to a single bed of the TSA unit, the steps of the TSA process applied to said single bed include:

[0032] 1) An adsorption step at an adsorption pressure and an adsorption temperature;

[0033] 2) An optional pressure reduction step of reducing the pressure to a regeneration pressure that can be lower than the adsorption pressure;

[0034] 3) A desorption step at a desorption temperature higher than the adsorption temperature;

[0035] 4) A cooling step of returning the TSA bed from the desorption temperature to the adsorption temperature; and

[0036] 5) A pressurization step of returning the TSA bed from the regeneration pressure to the adsorption pressure.

[0037] The adsorption step continues until the adsorbent no longer has sufficient available adsorption capacity to remove the target component to the target concentration. The desorption step continues until the TSA bed has regained sufficient available adsorption capacity to remove the target component. The adsorption step can be considered the adsorption mode, while the depressurization, desorption, cooling, and pressurization steps can be considered the regeneration mode.

[0038] In a swing bed operation, while the first TSA bed is in the adsorption step and in use, the second TSA bed can undergo the depressurization, desorption, cooling, and pressurization steps. However, the third TSA bed can be in a standby mode, fully regenerated and ready for use. Any number of TSA beds can be in an active service, regeneration, or standby mode. For simplicity, the present disclosure focuses on a two-bed TSA process. However, it should be understood that a three-bed TSA process or even a four-bed TSA process may be beneficial. Additionally, the regeneration of the TSA bed can occur in a flow direction that is co-current or counter-current to the flow direction of the adsorption mode.

[0039] Reference Figure 1A and 1B and, the gas fermentation zone includes at least one bioreactor 100 that converts the treated gaseous feedstock 122 to produce at least one target product stream 138 that includes at least one product and a tail gas stream, also referred to as a tail gas stream 136 that includes at least CO2. The treated gaseous feedstock 122 is from a feedstock source 102 and optionally a compressor 106 and is subsequently treated using a TSA process that includes adsorbent beds 116, 118, and 120. A TSA process is described where the regeneration mode of the adsorbent bed occurs in a fluid flow direction that is counter-current to the fluid flow in the adsorption mode. It is contemplated that in another embodiment, the regeneration mode of the adsorbent bed can occur in a co-current fluid flow direction.

[0040] The feedstock source 102 provides a gaseous feedstock 104. Suitable feedstock sources were described above. The gaseous feedstock 104 is compressed in a compressor 106 to produce a compressed gaseous feedstock 108. Valves 110, 112, and 114 control the fluid flow of the compressed gaseous feedstock 108, as shown by 108a, 108b, and 108c, to each of the corresponding adsorbent beds 116, 118, and 120. As Figure 1A and 1B depicted, the first adsorbent bed 116 contains active adsorbent and is in the adsorption mode, while the second adsorbent bed 118 contains spent adsorbent that has a reduced adsorption capacity compared to fresh or regenerated adsorbent. In some embodiments, the spent adsorbent has reached capacity and cannot adsorb additional contaminants. As Figure 1A and 1BThe second adsorbent bed 118 shown is in the regeneration mode. The optional third adsorbent bed 120 has been regenerated and is ready for on-line service (the on-line service of the third adsorbent bed 120 is not shown).

[0041] In one embodiment, when in the adsorption mode, the first adsorbent bed 116 operates at an adsorption temperature in the range of about 40°C to about 60°C. In other embodiments, the adsorption temperature can be, for example, about 40°C to about 50°C or about 50°C to about 60°C. When the first adsorbent bed 116 is in the adsorption mode, valves 110 and 130 are open, thereby allowing the gaseous feed 108a to pass through the first adsorbent bed 116 for treatment by adsorbing at least one target pollutant and producing at least one treated gaseous feed 122a depleted of the target pollutant. The treated gaseous feed largely passes as stream 122 to the bioreactor 100 in the gas fermentation zone. To direct the gaseous feed 108a to the first adsorbent bed 116, valves 112 and 114 remain closed. Additionally, valves 150a and 124 are closed during adsorption.

[0042] The adsorption capacity of the second adsorbent bed 118 has decreased and it is in the regeneration mode. An adsorbent with a reduced capacity can be referred to as a spent adsorbent compared to fresh or regenerated adsorbent. The capacity of the adsorbent does not necessarily have to reach zero, and regeneration can be performed at any time when the adsorbent capacity has decreased. It is advantageous to use the tail gas stream 136 from the bioreactor 100 in the gas fermentation zone for adsorbent regeneration. The bioreactor in the gas fermentation zone produces a tail gas stream 136 and a target product stream 138. The tail gas stream 136 passes through valve 140 and the regeneration heater 142 to heat the tail gas stream 136 and produce a heated tail gas stream 144. The heated tail gas stream 144 passes through the open valve 126 when valves 128 and 124 are closed and reaches the second adsorbent bed 118, thereby providing a heated regeneration gas to desorb the pollutants from the adsorbent in the second adsorbent bed 118. Additionally, valves 112 and 132 are closed and valve 150b is open.

[0043] The regeneration temperature is higher than the adsorption temperature. In some embodiments, the regeneration temperature is in the range of about 150°C to about 200°C. In various embodiments, the regeneration temperature can be, for example, about 150°C to 160°C, or about 160°C to about 180°C or about 180°C to about 200°C.

[0044] During regeneration of the second adsorbent bed 118, the effluent stream 146b generated departs from the TSA bed 118 and is conveyed to a thermal oxidizer or other energy recovery or oxidation device 400. Valve 322 is used to control the flow of the effluent stream 146a r. The desorbed compounds from the TSA bed contain trace impurities, such as being rich in volatile organic compounds relative to the feed gas. The thermal oxidizer thermally destroys the trace impurities and typically recovers waste heat to increase the energy of the regeneration gas (i.e., the tail gas stream 160). When the TSA bed 118 is fully regenerated and operational, valves 112 and 132 are open, and valves 126 and 150b are closed.

[0045] Regenerating the second adsorbent bed 118 using the heated tail gas stream 144 eliminates the requirement for using an inert gas (e.g., nitrogen) for TSA regeneration. Techniques using nitrogen require a certain capital expenditure to produce and store nitrogen, and may subsequently also handle large amounts of contaminated nitrogen, as well as a dilute tail gas stream with low energy value. Similarly, regenerating the adsorbent bed with the tail gas stream from the bioreactor is advantageous compared to regeneration by the product gas, because typically at most about 10 volume % of the feed gas is lost during regeneration, as the desorbed compounds contained therein are difficult to recycle without further treatment / separation.

[0046] In some embodiments, the regeneration heater 142 is a flame heater that provides direct heat transfer from fuel combustion. The thermal energy released by fuel combustion enters an open space and is transferred to the gas / fluid within pipes arranged along the walls and top of the combustion chamber. In another embodiment, the regeneration heater includes an electric flame heater that uses electricity to increase the temperature of the tail gas stream. Depending on the application, the electric flame heater can be used for both direct heating and indirect heating. The electric flame heater can include, but is not limited to, immersion heaters, circulation heaters, and electrothermal fluid heaters. In another embodiment, saturated or superheated steam is used for heating. Other heat sources with suitable temperatures can be envisioned in these embodiments.

[0047] To cool the second adsorbent bed 118 after it has been regenerated, the treated gaseous feedstock from the first adsorbent bed 116 is in fluid communication with the second adsorbent bed 118. A portion of the treated gaseous feedstock 122a from the first TSA bed 116 passes through the second TSA bed 118 by opening valves 132 and 150b, thereby generating an effluent stream 146b that connects to the regeneration effluent gas header 410. At least a portion of the regeneration effluent gas 410r passes through the desorption cooler 240 by opening valve 318 to generate a cooling stream 192, which is compressed by a compressor 412 to overcome the pressure drop across the second TSA bed 118 and the associated pipes and valves. The compressed gas 192 then merges into the product gas header 122 by opening valve 326, enabling the recovery of product gas for cooling the second adsorbent bed 118, asFigure 1A As shown in. Cooling and further recycling the treated gaseous feedstock from the TSA bed to the feed gas helps achieve nearly 100% recovery of the feed gas. Figure 1A and 1B shows a cooling flow conduit integrated with the regeneration flow conduit, but in other embodiments, the conduits for each function can be independent.

[0048] In another embodiment, as Figure 1B shown, the cooled regeneration gas is recycled through the second TSA bed 118 by opening valves 226, 250b, 218, and 426, with valves 124, 128, 150a, 150c, and 322 closed. Once the adsorbent in the second TSA bed 118 approaches the adsorption temperature, the gas recycling is stopped, and once the second TSA bed 118 transitions to the adsorption stage, the remaining gas in the second TSA bed 118 is recovered in the product gas manifold.

[0049] The thermal oxidizer 400 heats trace impurities (such as volatile organic compounds (VOCs)) to a certain temperature usually above the autoignition temperature until they are oxidized. The oxidation process decomposes the harmful particulates into carbon dioxide, water, and trace amounts of other combustion by-products. The thermal oxidizer can be selected from direct flame thermal oxidizers, heat recovery type oxidizers, regenerative thermal oxidizers, catalytic thermal oxidizers, flameless thermal oxidizers, or any combination thereof. The first type of thermal oxidizer is the direct flame thermal oxidizer. The principle of operation of a direct fixed oxidizer is to introduce the combustion process gas stream into a part of the direct thermal oxidizer, where the temperature of the process gas stream is raised to the autoignition temperature or above, and is maintained at this temperature in the furnace section for the required residence time to achieve the desired VOC destruction efficiency. The second type of thermal oxidizer is the regenerative thermal oxidizer (RTO). The RTO uses ceramic beds that can be heated from a previous oxidation cycle to preheat the input gas to partially oxidize it. The preheated gas enters the combustion chamber, which can be heated by an external fuel source to reach the target oxidation temperature. This type of oxidizer is specifically designed for oxidizing large process gas streams with low organic compound concentrations, such as organic pollutants with a low percentage of VOCs in the process gas stream. The third type of thermal oxidizer is the heat recovery type oxidizer. The heat recovery type oxidizer has primary and / or secondary heat exchangers within the device. The primary heat exchanger preheats the incoming combustion air stream by recovering heat from the existing clean gas stream. This main heat recovery raises the temperature of the process gas stream before it enters the combustion chamber, resulting in lower fuel requirements for the oxidizer device.

[0050] According to the above discussion, the method for integrating the TSA process and the gas fermentation process includes the following steps: (a) providing a first TSA bed containing an adsorbent, a second TSA bed containing spent adsorbent, and a gas fermentation process including a bioreactor; (b) transferring a gaseous feedstock and at least one contaminant to the first TSA bed and producing a contaminant-depleted treated gaseous feedstock; (c) transferring a portion of the treated gaseous feedstock to the gas fermentation process to produce a tail gas stream and a gas fermentation product stream; (d) first passing at least a portion of the tail gas stream from the gas fermentation process through a heater to heat the tail gas stream to a desired regeneration temperature, and then transferring the heated tail gas stream to the second TSA bed to desorb the adsorbed contaminants and provide heated regenerated adsorbent; (e) then transferring at least a portion of the treated gaseous feedstock from the first TSA bed to the second TSA bed and passing it through the regenerated adsorbent to cool the heated regenerated adsorbent to the adsorption temperature and provide a regeneration effluent stream; (f) cooling and recompressing the regeneration effluent stream and combining the regeneration effluent stream from the second TSA bed with the treated gaseous feedstock from the first TSA bed, or transferring the effluent stream of the treated gaseous feedstock to the gas fermentation process, recycling the cooled regeneration effluent stream through the second TSA bed 118 to further cool the regenerated adsorbent, or any combination thereof. When repeating steps (a) to (f), the adsorption switch is periodically switched from the first adsorption bed to the second adsorption bed and vice versa, where one of the TSA beds contains an adsorbent and the other TSA bed contains spent adsorbent. In another embodiment, a third TSA bed 120 containing regenerated adsorbent is maintained in a standby mode. If the adsorbent contained in both the first TSA bed 116 and the second TSA bed 118 can no longer adsorb contaminants or support extended regeneration cycles or maintenance requirements and thus needs to be taken offline, the third TSA bed can be switched in operation. In such cases, the third TSA bed 120 will be in fluid communication with the bioreactor 100. The third TSA bed 120 will be used to regenerate the first TSA bed 116 or the second TSA bed 118. When the valve 114 is opened, the third TSA bed 120 can receive the gaseous feedstock.

[0051] In one embodiment, the first TSA bed 116 can be pressurized to correspond to the pressure of the gas fermentation feedstock such that adsorption occurs at the corresponding pressure. The pressure of the second TSA bed 118 can be reduced (depressurized) to correspond to the pressure of the tail gas stream 136 from the gas fermentation process or the pressure of the heated tail gas stream 144 such that regeneration occurs at the corresponding pressure.

[0052] In some embodiments, the tail gas stream 136 or the heated tail gas stream 144 from the bioreactor 100 passes through the scrubber 146. The scrubber advantageously removes trace product streams, such as ethanol, from the tail gas stream 136 or the heated tail gas stream 144. Thus, passing the tail gas stream 136 or the heated tail gas stream 144 through the scrubber 146 avoids additional cleaning of the TSA bed adsorbent bed and prevents loss of products that may be included in the tail gas stream 136 generated by the bioreactor 100.

[0053] Reference Figure 2A and 2B , according to an alternative embodiment, an integrated TSA bed and PSA bed are disclosed. The TSA is discussed above. Pressure swing adsorption (PSA) uses a bed of solid adsorbent to separate components, such as contaminants. The bed is then regenerated by reducing the pressure. The PSA technique is based on the affinity of gas molecules to reversibly bind to the adsorbent material. The corresponding forces acting between the gas molecules and the adsorbent material depend on the gas component, the type of adsorbent material, the partial pressure of the gas component, and the operating temperature. The separation effect is based on the difference in binding forces to the adsorbent material. The PSA process typically operates at a constant temperature and uses the effects of alternating pressure and species partial pressure to perform adsorption and desorption. Since no heating or cooling is required, short cycles can be achieved. Thus, the process allows for the economical removal of large amounts of impurities. Adsorption is typically carried out at a high pressure (and thus a high corresponding partial pressure) in the range of about 10 bar to about 40 bar until the equilibrium loading is reached. At this point, no additional adsorption capacity is available, and the adsorbent material can be regenerated. Such regeneration is achieved by adjusting the pressure to slightly above or below atmospheric pressure, thereby correspondingly reducing the equilibrium loading. Thus, the contaminants on the adsorbent material are desorbed, and the adsorbent material is regenerated. After the regeneration is terminated, the pressure is increased back to the adsorption pressure level, and the process starts over from the beginning.

[0054] Such as Figure 2AAs shown, the integrated TSA, PSA, and gas fermentation process and apparatus includes: a first TSA bed 516 containing an adsorbent, a second TSA bed 518 containing spent adsorbent (i.e., adsorbent that can no longer adequately adsorb contaminants), a first PSA bed 590 containing a PSA adsorbent, a second PSA bed 591 containing PSA spent adsorbent, and a gas fermentation process in a bioreactor 610. A source 500 of gaseous feed provides a gaseous feed stream 502. The gaseous feed 502 is optionally compressed in a compressor 504 to produce a compressed gaseous feed 506. When the feed inlet valve 510 is open, the compressed gaseous feed 506 enters the first TSA bed 516 to allow the gaseous feed 506 to enter the first TSA bed 516 through an inlet stream 508a for adsorption. For example, the first TSA bed 516 operates at the adsorption temperature as described above and adsorbs at least one contaminant from the gaseous feed to produce a contaminant-depleted TSA-treated gaseous feed 522a. However, the TSA-treated gaseous feed may contain excessive CO2 or other removable components. The first PSA bed 590 is in fluid communication with the first TSA bed such that the contaminant-depleted TSA-treated gaseous feed 522a enters the first PSA bed 590 through a stream 540 and passes through the adsorbent to adsorb CO2 or other components in the first PSA bed 590 to produce a first PSA bed-treated gaseous feed 630 rich in fermentation substrate species such as CO and H2. As used herein, the term "rich in" means that the outlet stream has a greater concentration of a specified component than the component in the inlet stream of the vessel. The first PSA bed 590 is in fluid communication with the bioreactor 610 such that the first PSA bed-treated gaseous feed 630 enters the bioreactor 610 through a valve 575a. The bioreactor 610 produces a gas fermentation product stream 600 containing, for example, ethanol. Pre-removing CO2 or other components by the first PSA bed 590 prior to gas fermentation helps to enrich the feed of the bioreactor 610 with feed components favorable for certain gas fermentations and can increase the yield of the product in the product stream 620. The spent adsorbent in the second PSA bed 591 is regenerated by reducing the operating pressure, thereby forming a PSA reject stream 570, which can be used as a regeneration gas for the TSA unit. As described above, the PSA reject stream is heated to the TSA regeneration heater 544 using a suitable heat source. The heated PSA reject gas then passes through the spent adsorbent in the second TSA bed 518, thereby transferring heat to the spent adsorbent. As the temperature of the adsorbent increases, the adsorbed contaminants are desorbed and carried out of the TSA bed by the regeneration gas, thereby forming a regeneration effluent stream 546b, which is sent to a thermal oxidizer or other suitable process. As Figure 2A As shown in, after the adsorbent is heated, it is necessary and finally the heater 544 is turned off, thereby allowing the cold PSA reject stream to cool the adsorbent to or near the adsorption temperature.

[0055] In another embodiment, a TSA unit is used to remove contaminants from the feed gas, and a PSA unit is used to remove contaminants from the fermentation off-gas, as Figure 2B shown. In this configuration, the fermentation off-gas 580 is optionally sent to a scrubber 440 to recover trace fermentation products contained in the fermentation off-gas 580. The scrubbed off-gas 581 is then directed to the PSA unit to remove bulk contaminants, such as carbon dioxide, to enrich the concentration of gaseous fermentation substrates (such as CO and H2) before sending the gas to the bioreactor 610. The PSA reject stream 570 is used as the regeneration gas for the second TSA bed as described above.

[0056] Unless otherwise indicated, the recitation of a range of values herein is merely intended to be a shorthand method of referring individually to each separate value falling within the range, and each separate value is incorporated into the specification as if it were individually recited herein. For example, any concentration range, percentage range, ratio range, integer range, dimension range, or thickness range should be understood to include any integer value within the recited range, and fractions thereof (e.g., tenths and hundredths of an integer), where appropriate.

[0057] Unless otherwise indicated herein or clearly contradicted by context, all methods described herein may be performed in any suitable order. Unless otherwise stated, the use of any and all examples or exemplary language (e.g., "such as") provided herein is merely intended to better illustrate the disclosure and does not pose a limitation on the scope of the disclosure. Any language in the specification should not be construed as indicating any non-claimed element as essential to practicing the disclosure.

[0058] Embodiments of the present disclosure

[0059] Embodiments of the present disclosure are described herein. Variations of these embodiments may become apparent to those of ordinary skill in the art after reading the foregoing description, and the use of such variations is intended, where appropriate, to be within the scope in which the present disclosure may be practiced in a manner different from that specifically described herein. Accordingly, the present disclosure includes all modifications and equivalents of the subject matter recited in the claims as permitted by applicable law. In addition, unless otherwise specified herein or otherwise clearly contradicted by context, the present disclosure covers any combination of the above elements in all possible variations thereof.

[0060] Example 1. A method for integrating a temperature swing adsorption process and a gas fermentation process, the method comprising:

[0061] (a) Provide a temperature swing adsorption process and a gas fermentation process, wherein the temperature swing adsorption process includes at least a first adsorption bed and a second adsorption bed, the first adsorption bed contains an adsorbent, the second adsorption bed contains spent adsorbent, and the gas fermentation process includes a bioreactor, and the bioreactor contains at least one C1-fixing microorganism in a nutrient solution;

[0062] (b) Transfer a gaseous feedstock containing CO, CO2, H2, CH4, or any combination thereof and at least one contaminant to the first adsorption bed operating at an adsorption temperature, adsorb the contaminant on the adsorbent, and produce a treated gaseous feedstock depleted of the contaminant;

[0063] (c) Transfer at least a portion of the treated gaseous feedstock to the gas fermentation process to produce a heated tail gas stream and a gas fermentation product stream containing gas fermentation products;

[0064] (d) First, transfer at least a portion of the heated tail gas stream from the gas fermentation process to the second adsorption bed at a regeneration temperature, and pass through the spent adsorbent to desorb the adsorbed contaminant and provide a heated regenerated adsorbent, wherein the regeneration temperature is greater than the adsorption temperature;

[0065] (e) Then, transfer at least a portion of the treated gaseous feedstock from the first adsorption bed to the second adsorption bed and pass through the regenerated adsorbent to cool the heated regenerated adsorbent to the adsorption temperature and provide an effluent stream of the treated gaseous feedstock; and

[0066] (f) Combine the effluent stream of the treated gaseous feedstock from the second adsorption bed with the treated gaseous feedstock from the first adsorption bed, or transfer the effluent stream of the treated gaseous feedstock to the gas fermentation process, or both.

[0067] Example 2. The method according to Example 1, further comprising periodically repeating the process.

[0068] Example 3. The method according to Example 1 or 2, further comprising a third adsorption bed in a standby mode, the third adsorption bed containing regenerated adsorbent.

[0069] Example 4. The method according to any one of the foregoing examples, further comprising passing the heated tail gas stream from the gas fermentation process through a scrubber to remove and recover gas fermentation products from the heated tail gas stream before transferring it to the first adsorption bed.

[0070] Example 5. The method according to any one of the preceding examples, wherein the adsorption temperature is in the range of about 40 °C to about 60 °C.

[0071] Example 6. The method according to any one of the preceding examples, wherein the regeneration temperature is in the range of about 150 °C to about 200 °C.

[0072] Example 7. The method according to any one of the preceding examples, wherein the gaseous feedstock is selected from industrial waste gas, syngas, biogas, landfill gas, direct air capture, or any combination thereof.

[0073] Example 8. The method according to any one of the preceding examples, wherein the syngas is produced by a reforming process, a partial oxidation process, a gasification process, or any combination thereof.

[0074] Example 9. The method according to any one of the preceding examples, wherein the industrial gas is obtained from a source selected from: steel manufacturing, non-ferrous product manufacturing, petroleum refining, power production, carbon black production, paper and pulp manufacturing, ammonia production, methanol production, coke manufacturing, petrochemical production, carbohydrate fermentation, cement manufacturing, aerobic digestion, anaerobic digestion, natural gas extraction, cellulose fermentation, oil extraction, industrial processing of geological reservoirs, processing of fossil resources, or any combination thereof.

[0075] Example 10. The method according to any one of the preceding examples, wherein the pollutant is selected from at least one of the following: hydrocarbons, oxygenates, sulfur compounds, nitrogen compounds, or any combination thereof.

[0076] Example 11. The method according to any one of the preceding examples, wherein the adsorbent or the spent adsorbent is selected from zeolite molecular sieves, activated carbon, silica gel, activated alumina, or any combination thereof.

[0077] Example 12. The method according to any one of the preceding examples, further comprising: (a) adjusting the operating pressure of the first adsorption bed to correspond to the pressure of the gaseous feedstock; (b) adjusting the operating pressure of the second adsorption bed to correspond to the pressure of the heated tail gas stream from the gas fermentation process; or both (a) and (b).

[0078] Example 13. A method for integrating a temperature swing adsorption process, a pressure swing adsorption process, and a gas fermentation process, the method comprising:

[0079] Provided are a temperature swing adsorption process, a pressure swing adsorption process, and a gas fermentation process. The temperature swing adsorption process includes at least a first TSA adsorption bed and a second TSA adsorption bed. The first TSA adsorption bed contains a TSA adsorbent, and the second TSA adsorption bed contains a TSA spent adsorbent. The pressure swing adsorption process includes at least a first PSA adsorption bed and a second PSA adsorption bed. The first PSA adsorption bed contains a PSA adsorbent, and the second PSA adsorption bed contains a PSA spent adsorbent. The gas fermentation process includes a bioreactor, and the bioreactor contains at least one C1-fixing microorganism in a nutrient solution. A gaseous feedstock containing CO, CO2, H2, CH4, or any combination thereof and at least one contaminant is transferred to the first TSA adsorption bed operating at an adsorption temperature. The contaminant is adsorbed on the TSA adsorbent, and a TSA-treated gaseous feedstock depleted of the contaminant is produced. At least a portion of the treated gaseous feedstock is transferred to the first PSA adsorption bed operating at an adsorption pressure. CO2 is adsorbed on the PSA adsorbent, and a PSA-treated gaseous feedstock depleted of CO2 is produced. The PSA-treated gaseous feedstock is transferred to the gas fermentation process to produce a gas fermentation product stream containing a gas fermentation product. First, at least a portion of the TSA-treated gaseous feedstock is transferred to the second PSA adsorption bed operating at a desorption pressure. CO2 is desorbed from the PSA spent adsorbent, and a PSA purge gas stream rich in CO is produced, wherein the desorption pressure is different from the adsorption pressure. And then at least a portion of the PSA purge gas stream is transferred from the second PSA adsorption bed to the second TSA adsorption bed at a desorption temperature to desorb the adsorbed contaminant and provide a TSA purge gas containing the contaminant and CO2.

[0080] Example 14. A method for integrating a temperature swing adsorption process, a pressure swing adsorption process, and a gas fermentation process, the method comprising:

[0081] Providing a temperature swing adsorption process, a pressure swing adsorption process, and a gas fermentation process. The temperature swing adsorption process includes at least a first TSA adsorption bed and a second TSA adsorption bed. The first TSA adsorption bed contains a TSA adsorbent, and the second TSA adsorption bed contains a TSA spent adsorbent. The pressure swing adsorption process includes at least a first PSA adsorption bed and a second PSA adsorption bed. The first PSA adsorption bed contains a PSA adsorbent, and the second PSA adsorption bed contains a PSA spent adsorbent. The gas fermentation process includes a bioreactor, and the bioreactor contains at least one C1-fixing microorganism in a nutrient solution.

[0082] A gaseous feedstock containing CO, CO2, H2, CH4, or any combination thereof, and at least one contaminant are passed to the first TSA adsorption bed operating at an adsorption temperature, the contaminant is adsorbed on the TSA adsorbent, and a TSA-treated gaseous feedstock depleted of the contaminant is produced;

[0083] At least a portion of the treated gaseous feedstock is passed to a gas fermentation process to produce a fermentation offgas and a gas fermentation product stream containing a gas fermentation product;

[0084] At least a portion of the fermentation offgas is passed to the first PSA adsorption bed operating at an adsorption pressure, CO2 is adsorbed on the PSA adsorbent, and a PSA-treated fermentation offgas depleted of CO2 and a PSA purge gas are produced;

[0085] At least a portion of the PSA purge gas is passed from the first PSA adsorption bed to the second TSA adsorption bed at a desorption temperature to desorb the adsorbed contaminant and provide a TSA purge gas containing the contaminant and CO2.

[0086] Example 15. An integrated temperature swing adsorption and gas fermentation apparatus, comprising:

[0087] A gaseous feedstock source unit, the gaseous feedstock source unit being in fluid communication with a first adsorption bed containing an adsorbent, the first adsorption bed further comprising a treated gaseous feedstock outlet;

[0088] A second adsorption bed, the second adsorption bed containing spent adsorbent and having an effluent outlet, wherein the treated gaseous feedstock outlet of the first adsorption bed is further in fluid communication with the second adsorption bed; and

[0089] A bioreactor of a gas fermentation apparatus, the bioreactor being in fluid communication with the treated gaseous feedstock outlet of the first adsorption bed and the effluent outlet of the second adsorption bed, the bioreactor comprising a tail gas outlet and a product stream outlet, the tail gas outlet being in fluid communication with the second adsorption bed.

[0090] Example 16. The apparatus according to Example 15, further comprising a third adsorption bed in a standby mode, the third adsorption bed containing regenerated adsorbent, the third adsorption bed being in fluid communication with the bioreactor.

[0091] Example 17. The apparatus according to Example 15, wherein a scrubber is in fluid communication with the tail gas outlet of the bioreactor, the scrubber being further in fluid communication with the second adsorption bed.

[0092] Example 18. The apparatus according to any one of embodiments 15, wherein each of the temperature swing adsorption bed and the bioreactor is in fluid communication with at least one on-off valve.

[0093] Example 19. The apparatus according to any one of embodiments 15, further comprising a regeneration heater in fluid communication with the tail gas outlet of the bioreactor.

[0094] Example 20. An integrated temperature swing adsorption, pressure swing adsorption and gas fermentation apparatus, comprising:

[0095] A gaseous feedstock source unit in fluid communication with a first TSA adsorption bed containing an adsorbent, the first TSA adsorption bed further comprising a treated gaseous feedstock outlet;

[0096] A first PSA adsorption bed containing a PSA adsorbent, the first PSA bed being in fluid communication with the treated gaseous feedstock outlet of the first TSA adsorption bed, wherein the first PSA adsorption bed is further in fluid communication with the bioreactor; and

[0097] A second PSA adsorption bed containing PSA spent adsorbent, in fluid communication with the treated gaseous feedstock outlet of the first TSA adsorption bed, wherein the second PSA adsorption bed is further in fluid communication with a second TSA adsorption bed containing TSA spent adsorbent.

Claims

1. A method for integrating a temperature swing adsorption process and a gas fermentation process, the method comprising: (a) providing a temperature swing adsorption process and a gas fermentation process, the temperature swing adsorption process comprising at least a first adsorption bed and a second adsorption bed, the first adsorption bed comprising an adsorbent, the second adsorption bed comprising spent adsorbent, the gas fermentation process comprising a bioreactor, the bioreactor comprising at least one C1 immobilized microorganism in a nutrient solution; (b) passing a gaseous feedstock comprising CO, CO2, H2, CH4 or any combination thereof and at least one contaminant to said first adsorption bed operated at an adsorption temperature, adsorbing said contaminant on said adsorbent, and producing a treated gaseous feedstock depleted of said contaminant; (c) passing at least a portion of the treated gaseous feedstock to the gas fermentation process to produce a heated tail gas stream and a gas fermentation product stream comprising gas fermentation products; (d) first passing at least a portion of the heated tail gas stream from the gas fermentation process to the second adsorbent bed at a regeneration temperature and passing through the spent adsorbent to desorb adsorbed pollutants and provide heated regenerated adsorbent, wherein the regeneration temperature is greater than the adsorption temperature; (e) then transferring at least a portion of the treated gaseous feed from the first adsorption bed to the second adsorption bed and through the regenerated adsorbent to cool the heated regenerated adsorbent to the adsorption temperature and provide an effluent stream of the treated gaseous feed; as well as (f) combining the effluent stream of the treated gaseous feedstock from the second adsorption bed with the treated gaseous feedstock from the first adsorption bed, or passing the effluent stream of the treated gaseous feedstock to the gas fermentation process, or both.

2. The method of claim 1, further comprising periodically repeating the process.

3. The method of claim 1, further comprising a third adsorption bed in a standby mode, the third adsorption bed comprising a regenerated adsorbent.

4. The method of claim 1, further comprising passing the heated tail gas stream from the gas fermentation process through a scrubber to remove and recover gas fermentation products from the heated tail gas stream prior to passing to the first adsorption bed.

5. The method of claim 1, wherein the adsorption temperature is in the range of about 40°C to about 60°C.

6. The method of claim 1, wherein the regeneration temperature is in the range of about 150°C to about 200°C.

7. The method of claim 1, wherein the gaseous feedstock is selected from industrial waste gas, syngas, biogas, landfill gas, direct air capture, or any combination thereof.

8. The method of claim 1, wherein the syngas is produced by a reforming process, a partial oxidation process, a gasification process, or any combination thereof.

9. The method of claim 1, wherein the industrial gas is obtained from a source selected from the group consisting of steel manufacturing, non-ferrous product manufacturing, petroleum refining, power generation, carbon black production, paper and pulp manufacturing, ammonia production, methanol production, coke manufacturing, petrochemical production, carbohydrate fermentation, cement manufacturing, aerobic digestion, anaerobic digestion, natural gas extraction, cellulose fermentation, oil extraction, industrial processing of geological reservoirs, processing fossil resources, or any combination thereof.

10. The method of claim 1, wherein the contaminant is selected from at least one of the following: hydrocarbons, oxygen-containing compounds, sulfur compounds, nitrogen compounds, or any combination thereof.

11. The method according to claim 1, wherein the adsorbent or the spent adsorbent is selected from zeolite molecular sieve, activated carbon, silica gel, activated alumina or any combination thereof.

12. The method of claim 1, further comprising: (a) adjusting the operating pressure of the first adsorption bed to correspond to the pressure of the gaseous feedstock; (b) adjusting the operating pressure of the second adsorption bed to correspond to the pressure of the heated tail gas stream from the gas fermentation process; or (c) Both (a) and (b).

13. A method for integrating a temperature swing adsorption process, a pressure swing adsorption process and a gas fermentation process, the method comprising: (a) providing a temperature swing adsorption process, a pressure swing adsorption process and a gas fermentation process, wherein the temperature swing adsorption process comprises at least a first TSA adsorption bed and a second TSA adsorption bed, wherein the first TSA adsorption bed comprises a TSA adsorbent and the second TSA adsorption bed comprises a spent TSA adsorbent, wherein the pressure swing adsorption process comprises at least a first PSA adsorption bed and a second PSA adsorption bed, wherein the first PSA adsorption bed comprises a PSA adsorbent and the second PSA adsorption bed comprises a spent PSA adsorbent, and wherein the gas fermentation process comprises a bioreactor, wherein the bioreactor comprises at least one C1 immobilized microorganism in a nutrient solution; (b) passing a gaseous feedstock comprising CO, CO2, H2, CH4 or any combination thereof and at least one contaminant to said first TSA adsorbent bed operated at an adsorption temperature, adsorbing said contaminant on said TSA adsorbent, and producing a TSA-treated gaseous feedstock depleted of said contaminant; (c) passing at least a portion of the treated gaseous feed to the first PSA adsorbent bed operated at an adsorption pressure, adsorbing CO2 on the PSA adsorbent, and producing a CO2-depleted PSA-treated gaseous feed; (d) passing the PSA-treated gaseous feedstock to a gas fermentation process to produce a gas fermentation product stream comprising a gas fermentation product; (e) first passing at least a portion of the TSA-treated gaseous feed to a second PSA adsorbent bed operated at a desorption pressure different from the adsorption pressure to desorb CO from the PSA spent adsorbent and produce a CO-rich PSA purge gas stream; as well as (f) then transferring at least a portion of the PSA purge gas stream from the second PSA adsorption bed to the second TSA adsorption bed at a desorption temperature to desorb the adsorbed pollutants and provide a TSA purge gas comprising the pollutants and CO2.

14. A method for integrating a temperature swing adsorption process, a pressure swing adsorption process and a gas fermentation process, the method comprising: (a) providing a temperature swing adsorption process, a pressure swing adsorption process and a gas fermentation process, wherein the temperature swing adsorption process comprises at least a first TSA adsorption bed and a second TSA adsorption bed, wherein the first TSA adsorption bed comprises a TSA adsorbent and the second TSA adsorption bed comprises a spent TSA adsorbent, wherein the pressure swing adsorption process comprises at least a first PSA adsorption bed and a second PSA adsorption bed, wherein the first PSA adsorption bed comprises a PSA adsorbent and the second PSA adsorption bed comprises a spent PSA adsorbent, and wherein the gas fermentation process comprises a bioreactor, wherein the bioreactor comprises at least one C1 immobilized microorganism in a nutrient solution; (b) passing a gaseous feedstock comprising CO, CO2, H2, CH4 or any combination thereof and at least one contaminant to said first TSA adsorbent bed operated at an adsorption temperature, adsorbing said contaminant on said TSA adsorbent, and producing a TSA-treated gaseous feedstock depleted of said contaminant; (c) passing at least a portion of the treated gaseous feedstock to a gas fermentation process to produce a fermentation off-gas and a gas fermentation product stream comprising a gas fermentation product; (d) passing at least a portion of the fermentation off-gas to the first PSA adsorption bed operated at an adsorption pressure to adsorb CO2 on the PSA adsorbent and produce a CO2-depleted PSA-treated fermentation off-gas and a PSA purge gas; (e) transferring at least a portion of the PSA purge gas from the first PSA adsorption bed to the second TSA adsorption bed at a desorption temperature to desorb the adsorbed contaminants and provide a TSA purge gas comprising the contaminants and CO2.

15. An integrated temperature swing adsorption and gas fermentation device, comprising: i. A gaseous feed source unit, the gaseous feed source unit being in fluid communication with a first adsorption bed comprising an adsorbent, the first adsorption bed further comprising a treated gaseous feed outlet; ii. a second adsorption bed comprising spent adsorbent and having an effluent outlet, wherein the treated gaseous feed outlet of the first adsorption bed is further in fluid communication with the second adsorption bed; and iii. A bioreactor of a gas fermentation device, wherein the bioreactor is fluidically connected to the treated gaseous feedstock outlet of the first adsorption bed and the effluent outlet of the second adsorption bed, and the bioreactor comprises a tail gas flow outlet and a product flow outlet, and the tail gas flow outlet is fluidically connected to the second adsorption bed.

16. The apparatus of claim 15, further comprising a third adsorption bed in standby mode, the third adsorption bed comprising a regenerated adsorbent, the third adsorption bed being in fluid communication with the bioreactor.

17. The apparatus of claim 15, wherein a scrubber is in fluid communication with the tail gas stream outlet of the bioreactor, the scrubber further being in fluid communication with the second adsorption bed.

18. The apparatus of claim 15, wherein each of the temperature swing adsorption bed and the bioreactor is in fluid communication with at least one on-off valve.

19. The apparatus of claim 15, further comprising a regeneration heater in fluid communication with the tail gas stream outlet of the bioreactor.

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