CN115369425A - Flue gas CO 2 Process and system for preparing synthesis gas by electrolysis - Google Patents
Flue gas CO 2 Process and system for preparing synthesis gas by electrolysis Download PDFInfo
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Abstract
The invention discloses a CO 2 A process and apparatus for producing synthesis gas by electrolysis. The process comprises the following steps: carbon dioxide enrichment step with lean CO 2 Electrolyte from CO 2 Absorption of CO in a gas source 2 Obtaining CO-rich 2 An electrolyte; an electrolyte circulation step of circulating the CO-rich 2 Electrolyte is fed into the cathode chamber of an electrochemical reactor while said lean CO is simultaneously fed 2 Electrolyte is fed into an anode cavity of the electrochemical reactor, catholyte discharged from the cathode cavity after electrolysis and anolyte discharged from the anode cavity are mixed and supplemented with water to obtain constant concentrationFixed lean CO 2 An electrolyte; and an electrolysis step of supplying direct current to the electrochemical reactor, the CO-rich being in a cathode chamber of the electrochemical reactor 2 CO in electrolyte 2 And water is catalytically reduced to synthesis gas while the CO is depleted in the anode chamber of the electrochemical reactor 2 The water in the electrolyte is catalytically oxidized to oxygen. Process of the invention for CO 2 CO in the gas source 2 Has strong concentration tolerance, can be suitable for high-purity gas source and low-concentration CO 2 Industrial gas source.
Description
Technical Field
The invention belongs to the field of resources and environmental protection, and particularly relates to CO 2 A process and a system for preparing synthesis gas by electrolysis.
Background
CO 2 The technology for preparing synthesis gas by electrolysis can combine green electricity to CO 2 The carbon-rich syngas is converted into the syngas which is an important chemical raw material, and has the environmental protection property of carbon emission reduction and the new energy property of energy storage, so that the carbon-rich syngas can be used for various CO 2 The utilization path and the application field are taken as the hot spots of research.
CO 2 The electrolytic synthesis gas production process is mainly completed by means of a two-chamber reaction unit having a cathode chamber and an anode chamber. The typical electrolysis process is a gas-liquid mixed electrolysis mode, and the process uses CO 2 The gas and the electrolyte are simultaneously and directly introduced into the cathode chamber to generate synthesis gas (CO and H) through electrolysis 2 Composition). The operation flow is simple, and raw materials only consume CO 2 And water, so the scalability is strong. But still has serious problems: the first defect is that the requirement on the quality of the gas source is harsh, and a high-purity gas source is needed. However, CO is emitted industrially 2 The gas sources such as power plant flue gas, coal-fired boiler flue gas, cement kiln tail gas, chemical industry flue gas and the like all have CO 2 Low concentration and containing a large amount of N 2 、O 2 、NO x 、SO x、 Dust and other impurities, and if the gas source is directly used, on one hand, the safety of the gas source in the electrolysis process is threatened, and meanwhile, the existence of the impurities greatly reduces the service life of the electrocatalyst and the reactor, so that the application of the process in the carbon emission industry is limited. This requires a highly dependent carbon capture, with CO from such sources 2 Further purification and reuse of CO inevitably increase 2 And (5) comprehensive utilization cost. Secondly, the surface of the catalyst is covered by a large amount of electrolyte in the traditional gas-liquid mixed electrolysis process, and CO is generated 2 Limited mass transfer on the surface, severe hydrogen evolution side reaction and large amount of CO 2 Does not participate in the conversion, and leads the subsequent gas separation and purification operation of the product to be more complex and finishedThe method is expensive, so that the carbon emission reduction effect of the technology is not obvious, and meanwhile, the economy is poor.
Disclosure of Invention
The invention aims to solve the problems and provides a method for preparing a catalyst suitable for CO with different concentrations 2 The gas source and carbon emission reduction effect is obvious, and CO can be effectively reduced 2 The novel electrolysis process for producing the synthesis gas by electrolysis is used for accelerating the engineering application process of the technology.
The invention provides a flue gas CO 2 The electrolysis synthesis gas preparation process comprises the following steps: carbon dioxide enrichment step with lean CO 2 Electrolyte from CO 2 Absorption of CO in a gas source 2 Obtaining CO-rich 2 An electrolyte; an electrolyte circulation step of circulating the CO-rich 2 Electrolyte is fed into the cathode chamber of an electrochemical reactor while said CO is depleted 2 Electrolyte is fed into the anode chamber of the electrochemical reactor, catholyte discharged from the cathode chamber after electrolysis and anolyte discharged from the anode chamber are mixed and supplemented with water to obtain CO-lean solution with constant concentration 2 An electrolyte; and an electrolysis step of supplying direct current to the electrochemical reactor, the CO-rich being in a cathode chamber of the electrochemical reactor 2 CO in electrolyte 2 And water is catalytically reduced to synthesis gas while the CO is depleted in the anode chamber of the electrochemical reactor 2 The water in the electrolyte is catalytically oxidized to oxygen.
According to an embodiment of the present invention, the absorption pressure in the carbon dioxide enrichment step is 10kPa to 5MPa, and the absorption temperature is 5 to 90 ℃; the electrolysis temperature of the electrochemical reactor is 5-90 ℃, and the electrolysis pressure is 10kPa-5MPa.
According to another embodiment of the invention, the lean CO 2 The electrolyte is an alkaline electrolyte, preferably an alkali metal bicarbonate or carbonate electrolyte; the alkali metal is one or more of lithium, sodium, potassium, rubidium and cesium, preferably potassium and sodium, and the concentration of the metal ions in the electrolyte is 0.05-6mol/L.
According to another embodiment of the invention, the CO enrichment 2 The pH value of the electrolyte is 6-11.
According to another aspect of the present inventionEmbodiment(s) the CO 2 CO in gas source 2 The volume content is more than or equal to 3 percent.
According to another embodiment of the invention, the absorption of CO is carried out 2 Before, the method also comprises the step of treating the CO 2 Removing impurities from gas source to remove CO 2 Powders, particles in the gas source and gases harmful to the electrochemical reactor.
According to another embodiment of the present invention, the system may be in a pressure equalization condition, i.e. said electrolysis pressure is equal to the absorption pressure of said carbon dioxide enrichment module. The pressure can also be non-uniform working condition, namely the electrolysis pressure is not equal to the absorption pressure of the carbon dioxide enrichment module; pressure equalization conditions are preferred.
The invention also provides CO 2 An electrolysis synthesis gas production system comprising: carbon dioxide enrichment module for using lean CO 2 Electrolyte from CO 2 Absorption of CO in a gas source 2 Obtaining CO-rich 2 An electrolyte; an electrolysis module comprising an electrochemical reactor, the CO-rich in a cathode chamber of the electrochemical reactor 2 CO in electrolyte 2 And water is catalytically reduced to synthesis gas while the CO is depleted in the anode chamber of the electrochemical reactor 2 Water in the electrolyte is catalytically oxidized into oxygen; and an electrolyte circulation module for supplying the electrolysis module with the CO-rich gas 2 Electrolyte and the CO lean 2 Electrolyte, and mixing and replenishing the electrolyte discharged from the cathode and the anode of the electrolysis module to obtain CO-poor electrolyte with constant concentration 2 And (3) an electrolyte.
According to another embodiment of the invention, the carbon dioxide enrichment module further comprises a depuration unit for the removal of the CO 2 Particulate matter in the gas source and gases harmful to the electrochemical reactor.
The invention provides flue gas CO 2 Process and system for producing synthesis gas by enrichment electrolysis by absorbing CO with alkaline electrolyte in electrolyte circulation step 2 Function realization of CO 2 The enrichment in the electrolyte is integrated with the electrolysis. The process has the advantages that: to CO 2 CO in gas source 2 Has strong concentration tolerance, can be suitable for high-purity gas sources and also can be used forSuitable for low concentration CO 2 Industrial gas source, so that the technology can be applied to CO in various industries 2 The gas source has universality; compared with the traditional gas-liquid mixed electrolysis process, the process has weaker dependence on carbon capture, realizes carbon dioxide enrichment synchronously by depending on an electrolysis system, has simple process operation flow, effectively improves the concentration of the synthesis gas in the product gas, reduces the separation cost and the carbon utilization cost of the product gas, and improves the CO 2 Efficiency of utilization and economy.
Drawings
FIG. 1 is CO of example 1 2 A process flow chart for preparing synthesis gas by electrolysis.
FIG. 2 is CO of example 1 2 Schematic diagram of a system for producing synthesis gas by electrolysis.
FIG. 3 is CO of example 3 2 A schematic diagram of a system for producing synthesis gas by electrolysis.
FIG. 4 is CO of example 4 2 A process flow chart for preparing synthesis gas by electrolysis.
FIG. 5 is CO of example 4 2 Schematic diagram of a system for producing synthesis gas by electrolysis.
Detailed Description
The present invention will be described in detail with reference to the following embodiments.
The invention provides flue gas CO 2 Process for producing synthesis gas by electrolysis with industrial CO 2 Gas source and water are used as raw materials, and synthesis gas (CO + H) is obtained through a carbon dioxide enrichment step, an electrolyte circulation step and an electrolysis step 2 ) And oxygen (O) 2 ). Further comprises a product gas purification step, wherein the synthesis gas and the oxygen obtained in the first three steps can be further separated and purified by the step to respectively obtain a synthesis gas product and an oxygen byproduct, and the CO separated in the step 2 Can be returned to the carbon dioxide enrichment step for recycling. The process of the present invention will be described in detail below.
The carbon dioxide enrichment step being lean in CO 2 Electrolyte from CO 2 Gas source absorbing CO 2 Obtaining CO-rich 2 And (3) an electrolyte. This step can be carried out by reacting with CO 2 Pressurizing the gas source to make the gas lean in CO 2 The electrolyte can absorb CO in a gas source 2 Obtaining CO-rich 2 And (3) an electrolyte. Hereinafter toFor convenience of description, the "electrolyte" includes "CO lean 2 Electrolyte "and" rich in CO 2 An electrolytic solution ".
The step can also comprise a process of impurity removal in the enrichment of CO 2 Previously, it was possible to treat CO 2 And removing impurities from the gas source, removing particulate impurities in the gas source, and removing gas harmful to a subsequent electrochemical reactor. CO 2 2 The gas source generally comes from the industries of chemical industry, thermoelectricity, cement, steel and the like, can be a high-purity gas source, can also be a low-concentration gas source, and can contain H 2 S、SO x 、NO x 、NH 3 、NH 2 CH 2 OH, dust and the like. Wherein O is 2 Or N 2 The impurities can cause CO in the gas source 2 Partial pressure is reduced to influence CO 2 Absorption and enrichment of H 2 S、SO x 、NO x 、NH 3 、NH 2 CH 2 Impurities such as OH, dust, etc., which affect the life of the catalytic electrode in the electrochemical reactor, are called harmful impurities, and therefore need to be present in CO 2 It is removed prior to enrichment. The method of removing impurities may be any suitable method, and will be described in detail hereinafter.
The electrolyte circulation step comprises enriching CO 2 Electrolyte is fed into the cathode chamber of an electrochemical reactor while being lean in CO 2 The electrolyte is fed into the anode chamber of the electrochemical reactor. The electrolyzed gas-liquid mixture in the cathode cavity and the gas-liquid mixture in the anode cavity are respectively subjected to gas-liquid separation to obtain catholyte and anolyte, and water consumed by reaction is supplemented into the catholyte to obtain CO-poor solution with constant concentration 2 And recycling the electrolyte. And respectively obtaining cathode mixed gas and anode mixed gas after gas-liquid separation, respectively obtaining synthesis gas and oxygen after cooling and dehydrating, and respectively converging the electrolytes cooled from the cathode mixed gas and the anode mixed gas into cathode electrolyte and anode electrolyte.
The electrolysis step is to supply direct current to the electrochemical reactor where in the cathode chamber of the reactor the CO is enriched 2 CO in electrolyte 2 And water is catalytically reduced to synthesis gas while being lean in CO in the reactor anode chamber 2 The water in the electrolyte is catalytically oxidized to oxygen. The specific reaction principle is as follows: rich in CO 2 CO in electrolyte 2 And H 2 O is reduced and converted into synthesis gas and OH under the action of a cathode catalytic electrode in a cathode cavity - And is simultaneously lean in CO 2 In electrolyte H 2 O is oxidized into O under the action of the anode cavity anode catalytic electrode 2 In the anode cavity M + Then from the cation exchange membrane to the cathode chamber. The electrolysis process reacts as follows:
an anode cavity: h 2 O→0.5O 2 +2H + +2e -
2H + +2HCO 3 - →2H 2 CO 3
A cathode cavity: xCO 2 +xH 2 O+2xe - →xCO+2xOH-
2(1-x)H 2 O+2(1-x)e - →(1-x)H 2 +2(1-x)OH -
Reaction in an electrolyte: 2H 2 CO 3 +2OH - →2HCO 3 - +2H 2 O
And (3) total reaction: xCO 2 +(1-x)H 2 O→xCO+(1-x)H 2 +0.5O 2
M in the catholyte discharged after the reaction + The concentration and the pH value are increased, and M in the electrolyte discharged from the anode after the reaction + The concentration and pH value are reduced, and two solutions are mixed to realize pH value and MHCO 3 And (4) mixing the concentrations. Therefore, the electrolyte only needs to be introduced before starting up, no electrolyte is consumed in the conversion process, and water consumed in the reaction process can be added through the water replenishing unit. The whole synthesis route only consumes water and CO 2 Meanwhile, other substances are not required to be introduced, the operation is simple, and the cost is low.
The invention obtains the CO in a dissolved state through an enrichment step 2 Is rich in CO 2 The electrolyte can directly contact with the catalyst, mass transfer limitation is effectively reduced, and reaction efficiency is improved compared with a traditional gas-liquid mixing mode.
The product gas purification step can purify and purify the synthesis gas to obtain the synthesis gasGas production and separation of unreacted CO 2 ，CO 2 Can be returned to the carbon dioxide enrichment step for recycling. The product gas purification step can also purify oxygen to obtain oxygen byproduct and separate out residual CO 2 ，CO 2 Can be returned to the carbon dioxide enrichment step for recycling.
In an alternative embodiment, CO 2 CO in gas source 2 The volume content is more than or equal to 3 percent, and the carbon dioxide can be a high-purity gas source and can also be low-partial pressure CO 2 Flue gas and chemical product gas.
In an alternative embodiment, the absorption pressure (gauge pressure) in the carbon dioxide enriching step is 10kPa to 5MPa, the absorption temperature is 5 to 90 ℃, and the outlet of the absorption column is rich in CO 2 The pH value of the electrolyte is 6-11. The electrolysis temperature of the electrochemical reactor is 5-90 ℃, and the electrolysis pressure (gauge pressure) is 10kPa-5MPa. In an optional embodiment, the absorption pressure can be equal to the electrolysis pressure, the electrolysis pressure is systematically controlled through the electrolyte circulation step, and at the moment, the whole process system is under the condition of pressure equalizing working condition, so that the complexity of pressure control can be reduced; when the absorption pressure is greater than the electrolysis pressure, the pressure difference exists between the enrichment module and the electrolysis module at the moment, namely the non-isobaric working condition, the defects are that the complexity of pressure control of the whole process pipeline and the system is increased, and CO is easily caused 2 The gas escapes from the liquid phase to influence the electrolysis efficiency, and the advantage is that the pressure difference can be used as the power for conveying the electrolyte of the enrichment module to the electrolysis module; the present invention can also be achieved when the absorption pressure is less than the electrolysis pressure, in which case there is also a pressure difference that complicates the system equipment process piping and system pressure control, and therefore, from the viewpoint of electrolysis efficiency and process equipment simplification, it is preferable that the absorption pressure be equal to the electrolysis pressure.
The electrolyte is an alkaline electrolyte, preferably an alkali metal bicarbonate (MHCO) 3 ) Or a carbonate (M) 2 CO 3 ) And (3) an electrolyte. The alkali metal (M) may be lithium, sodium, potassium, rubidium, cesium, preferably potassium and sodium, and the metal ion concentration is 0.05-6mol/L.
The invention also provides CO 2 The system for preparing the synthesis gas by enrichment electrolysis comprises a carbon dioxide enrichment module, an electrolyte circulation module and an electrolysis module. Still further, the product gas can be includedAnd a purification module.
The carbon dioxide enrichment module is used for concentrating CO 2 And (4) absorbing and enriching by a gas source. Can comprise a raw material gas supply unit, CO 2 An absorption unit. When CO is present 2 When the gas source contains harmful impurities, the gas source also comprises an impurity removal unit. When it is necessary to treat CO 2 When the tail gas is recycled, the tail gas also comprises CO 2 And a circulation unit. When CO is present 2 When the pressure of the gas source is not higher than the pressure of the absorption unit and the impurity removal unit, the feed gas supply unit comprises a buffer tank and a supercharger, wherein the upstream of the supercharger is sequentially connected with the buffer tank and CO 2 A gas source connected downstream to the CO 2 The absorption unit or the impurity removal unit is connected when CO is used 2 When the pressure of the gas source is higher than the pressure of the absorption unit and the pressure of the impurity removal unit, the feed gas supply unit can only comprise a buffer tank; the absorption unit comprises an absorption tower for absorbing CO 2 When the gas source has no harmful impurities, the upstream of the gas source can be directly connected with a raw gas supply unit, and when CO is generated 2 When the gas source contains harmful impurities, the upstream is connected with the impurity removal unit, the downstream is connected with the electrolyte circulation module, and the electrolyte circulation module can also be simultaneously connected with CO 2 The circulating units are connected; the impurity removal unit comprises one elution tower or a plurality of elution towers which are connected in series or in parallel, the upstream of the elution tower is connected with the raw material gas supply unit, and the downstream of the elution tower is connected with the absorption tower; CO 2 2 The circulation unit comprises a front buffer tank, a supercharging device and a rear buffer tank, wherein the upstream of the front buffer tank is connected with the product gas purification module and also can be connected with the top of the absorption tower simultaneously, the front buffer tank, the supercharger and the rear buffer tank are sequentially connected, and the downstream of the rear buffer tank is connected with the absorption module. The supercharging device may be either a fan or a compressor. CO 2 2 The tail gas is absorption tower top tail gas and/or product gas purification module CO 2 And (4) tail gas.
Electrolytic module for generating CO 2 To produce synthesis gas. At least one electrochemical reaction unit and a control power source may be included. The electrochemical unit comprises at least one electrochemical reactor, each electrochemical reactor at least comprises 1 groove, each groove is composed of 1 cathode chamber/diaphragm/anode chamber, when comprising a plurality of grooves, the grooves can be connected in series and/or in parallel to form one reactor, and the system can comprise one or more reactors. The diaphragm is a cation exchange membrane or an anion exchange membraneAn ion exchange membrane. The upstream of the cathode cavity is connected with the absorption tower, the downstream of the cathode cavity is connected with the electrolyte circulating unit, and the upstream and the downstream of the anode cavity are both connected with the electrolyte circulating unit. The control power supply is used for providing direct current for the electrochemical reaction unit.
The electrolyte circulation module is used for supplying electrolyte to the electrolysis unit, and separating and mixing the electrolysis products. An electrolyte delivery unit, a gas-liquid separation unit, a mixing unit, and a water replenishing unit may be included. The electrolyte conveying unit comprises an anode circulating pump, a relay pump and/or a cathode circulating pump, the upstream of the anode circulating pump is connected with the mixing unit, the downstream of the anode circulating pump can be connected with the anode cavity, and can also be directly connected with the absorption tower to directly serve as energy supply of the relay pump, the upstream and downstream of the relay pump are respectively connected with the mixing unit and the absorption tower, and the upstream and downstream of the cathode circulating pump are respectively connected with the absorption tower and the cathode cavity. The gas-liquid separation unit comprises a cathode gas-liquid separator, a cathode gas-phase cooling tower, an anode gas-liquid separator and an anode gas-phase cooling tower, wherein the upstream of the cathode gas-phase cold scarifier is sequentially connected with the cathode gas-liquid separator and a cathode cavity of the electrolysis unit, the gas phase is subjected to cold scarification, cold scarified liquid returns to the cathode gas-liquid separator, the downstream of the cathode gas-phase cold scarifier can be further purified by a product gas purification module to obtain a synthetic gas product, the upstream of the anode gas-phase cold scarifier is sequentially connected with the anode gas-liquid separator and an anode cavity of the electrolysis unit to obtain oxygen, the gas phase is cooled, the cooling liquid returns to the anode gas-liquid separator, and the downstream of the anode gas-phase cold scarifier can be further purified by the product gas purification unit to obtain an oxygen byproduct. The mixing unit is a mixing tank or a liquid mixer, the upstream of the mixing unit is respectively connected with the cathode gas-liquid separator and the anode gas-liquid separator, and the downstream of the mixing unit is respectively connected with the anode circulating pump and the relay pump. The water replenishing unit comprises a water replenishing pump and a water tank, wherein the upstream of the water replenishing pump is connected with the water tank, and the downstream of the water replenishing pump is connected with any one or more of the cathode gas-liquid separation tank, the anode gas-liquid separation tank or the mixing unit.
The product gas purification module is used for purifying and separating the synthesis gas and/or oxygen and separating the non-reversely converted CO 2 . A syngas purification unit and/or an oxygen purification unit may be included. The purification unit can be any one of membrane separation device, pressure swing adsorption device, temperature swing adsorption device, chemical absorption device, etcOne kind of the medicine. The upper stream of the synthesis gas purification unit is connected with the cathode gas phase cold area device to produce synthesis gas products and output CO 2 Tail gas and CO 2 The front buffer tank of the circulation unit is connected. The upstream of the oxygen purification unit is connected with the anode gas phase cold area device to produce oxygen by-product and output CO 2 Tail gas and CO 2 The front buffer tank of the circulation unit is connected.
The absorption pressure (gauge pressure) of the absorption tower of the system is between 10kPa and 5MPa, and the pressure (gauge pressure) of the electrolysis module is between 10kPa and 5MPa, and the two pressures can be equal or different. The electrolysis pressure is divided into cathode side pressure and anode side pressure, the cathode side pressure is controlled by a cathode gas-liquid separator or cathode gas-phase cooler gas outlet pressure regulating valve, the anode side pressure is controlled by an anode gas-liquid separator and anode gas-phase cooler gas outlet pressure regulating valve, and the pressure difference between the cathode side pressure and the anode side pressure is lower than 50kPa.
In an alternative embodiment, when the absorber pressure is higher than the electrolysis cell pressure, the absorber is rich in CO 2 The electrolyte can be fed into the cathode cavity from a pipeline between the absorption tower and the cathode cavity by means of the pressure difference between the two, and the cathode circulating pump can be omitted or does not work at the moment. When the pressure in the absorption tower is equal to the operating pressure of the electrolyte circulation module, the absorption tower is rich in CO 2 The electrolyte needs to be transported into the cathode cavity of the electrolysis unit by a cathode circulating pump.
In an alternative embodiment, the mixing unit is lean in CO downstream of the anode circulation pump while the anode chamber and the absorption column are connected 2 The electrolyte is delivered into the anode cavity and the absorption tower of the electrolysis unit, the relay pump can be omitted, and when the downstream of the anode circulating pump is only connected with the anode cavity, the CO of the mixing unit is depleted 2 When the electrolyte is conveyed to an anode cavity of the electrolysis unit, a relay pump is needed to be respectively connected with the mixing unit and the absorption tower at the upstream and the downstream to ensure that the poor CO is obtained 2 And feeding the electrolyte into an absorption tower.
The purity of the synthesis gas product or the oxygen product discharged from the product gas purification device mainly depends on the downstream application requirements of the synthesis gas or the oxygen product. In an alternative embodiment, the purification unit converts CO from the synthesis gas 2 Purifying to 3-6 vol% for low pressure synthesis of methanol to separate CO 2 Returning the gas to the absorption tower for cyclic utilization. In the alternative embodimentIn one embodiment, the purification device removes CO from the syngas 2 Purifying to less than or equal to 15 percent, and can be used for Fischer-Tropsch synthesis of oil wax. In an alternative embodiment, the oxygen is treated with CO 2 Purifying to less than or equal to 0.8% and can be used for industrial production or processing gas.
CO 2 The gas source is generally from the industries of chemical industry, thermoelectricity, cement, steel and the like, can be a high-purity gas source, can also be a low-concentration gas source, and can contain H 2 S、SO x 、NO x 、NH 3 、NH 2 CH 2 OH, dust and the like. Wherein O is 2 Or N 2 The impurities can cause CO in the gas source 2 Partial pressure is reduced to influence CO 2 Absorption enrichment, but no detrimental effect on the electrolysis reaction, and H 2 S、SO x 、NO x 、NH 3 、NH 2 CH 2 OH, dust and other impurities in high content can affect the performance of the electrolytic module, are called harmful impurities, and need to be in CO 2 The front-end elution column of the absorption column is removed to a lower concentration. The elution tower can be formed by one or more serial or parallel connection towers, and the elution tower can be in a single-way type or can be repeatedly eluted for multiple times so as to remove harmful impurities. The adsorption medium in the tower can be in a liquid state and comprises any one of pure water, an acidic solution and an alkaline solution. Or a dry filter medium, such as a filter cloth, a filter screen and the like, or a dry adsorbent or catalytic oxidizer, including any one or more of activated carbon, zeolite, quicklime, alumina, aluminosilicate, zinc oxide, nickel oxide, iron oxide, silicon oxide, copper hydroxide and copper sulfate. The acidic solution comprises HCl and H 2 SO 4 、HNO 3 Any one or more of. The alkaline solution comprises KOH, naOH and K 2 CO 3 、Na 2 CO 3 、KHCO 3 、NaHCO 3 、Na 2 SO 3 、Ca(OH) 2 、CuSO 4 、Pb(NO 3 ) 2 And one or more of methanol, monoethanolamine diethanolamine, triethanolamine, diisopropanolamine and methyldiethanolamine.
In an alternative embodiment, CO 2 The gas source is high-concentration gas (CO) 2 Concentration ofNot less than 98%) or contains O 2 、N 2 Impurities (CO) 2 Concentration is more than or equal to 5%), then the gas source can directly enter CO 2 The absorption tower is enriched without being subjected to an elution tower to remove impurities. In this alternative embodiment, CO 2 The gas source contains dust particles (CO) 2 The concentration is more than or equal to 5 percent), the dust is removed by an elution tower until the dust content is less than or equal to 5mg/m 3 Then, enters CO 2 The absorption tower is enriched, and the medium in the elution tower can be any one of pure water, acid solution or dry medium. In an alternative embodiment, CO 2 In the gas source, e.g. containing NO x 、SO x 、H 2 One or more acidic gases in S need to be removed to NO by an elution tower x The content is less than or equal to 30mg/m 3 、SO x The content is less than or equal to 30mg/m 3 、H 2 The S content is less than or equal to 15ppm, and the CO can enter 2 The absorption tower is enriched, and the medium in the elution tower can be alkaline solution or dry medium. In an alternative embodiment, CO 2 Gas source containing, for example, NH 3 Alkaline gases such as ethanolamine and the like can be subjected to impurity removal by an elution tower, and then the impurities can enter CO 2 The absorption tower is rich, and the medium in the elution tower can be any one of acid medium or dry medium.
The cathode cavity of the electrochemical reactor contains a cathode catalytic electrode, the anode cavity contains an anode catalytic electrode, and the middle of the anode catalytic electrode is separated by an ion exchange membrane. The cathode catalytic electrode can be formed by coating a cathode catalyst on an ion exchange membrane to form a catalytic membrane electrode, or can be formed by a carrier and the cathode catalyst coated on the surface of the carrier, wherein the carrier is any one of titanium mesh, foamed titanium, nickel mesh, foamed nickel and carbon paper, the cathode catalyst is any one of porous N-C, ni-N-C, zn-N-C, ag-N-C, cu-N-C, co-N-C and the like, or any one of nano-scale metal simple substances, oxides or any two-component alloy or mixed oxides of Ni, zn, sn, ag, cu, co and In, the catalyst can be In a supported type or a non-supported type, and the carrier is selected from carbon powder, graphene, carbon nano tubes, carbon black or carbon fibers. The anode catalytic electrode can be formed by coating an anode catalyst on an ion exchange membrane to form a catalytic membrane electrode, or can be formed by a carrier and the anode catalyst coated on the surface of the carrier, wherein the carrier is selected from a titanium net, a titanium plate, a nickel net and a stainless steel net. The anode catalyst is any one of supported or unsupported Ir, pt, ru, ti, co, sn, fe, sb, pb, zr, ni and Ce two-phase or multi-phase oxide solid solutions, and the carrier is selected from carbon powder, graphene, carbon nano tubes, carbon black or carbon fibers.
The electrolysis reaction unit is powered by a power supply to supply direct current for electrolyzing CO 2 Syngas and oxygen are produced. As mentioned above, no electrolyte is consumed during the conversion process, the electrolyte only needs to be introduced before starting up, and the water consumed during the reaction process can be added through the water replenishing unit. The whole synthesis route only consumes water and CO 2 Meanwhile, other substances are not required to be introduced, the operation is simple, and the cost is low.
The invention is further described below by means of specific examples. However, these examples are only illustrative and do not set any limit to the scope of the present invention.
In the following examples and comparative examples, reagents, materials and instruments used therefor were commercially available unless otherwise specified.
Unless otherwise specified, specific pressure values in the following examples are gauge pressures.
Example 1
FIG. 1 shows CO in this example 2 A process flow chart for preparing synthesis gas by electrolysis. The specific process operation flow comprises three steps of carbon dioxide enrichment, electrolysis and electrolyte circulation. 1.89Nm 3 CO of/h 2 Gas source (from desulfurization and denitrification flue gas of certain gas boiler plant, CO) 2 12% by volume of NO x The content is less than or equal to 30mg/m 3 、SO x The content is less than or equal to 30mg/m 3 Dust is less than or equal to 5mg/m 3 ) Pressurizing to 0.6MPa by a fan, feeding into an absorption tower, controlling the temperature of the absorption tower to be 60 ℃, and simultaneously using a relay pump to ensure that the lean CO in the liquid mixer is fed 2 Electrolyte (KHCO) 3 Concentration of 1 mol/L) is conveyed into an absorption tower for enrichment to obtain CO-rich 2 Electrolyte, pH =8.3. This rich in CO 2 The electrolyte is fed into the cathode cavity of the electrochemical reactor through a cathode circulating pump, and meanwhile, the anode circulating pump also leads the lean CO in the liquid mixer 2 Electrolyte solutionIs sent into the anode cavity of the electrochemical reactor. Controlling the electrolysis current to be 600A, and taking CO rich at the inlet of the reactor at the electrolysis temperature 2 Electrolyte temperature and outlet lean CO 2 Average temperature of the electrolyte. CO enrichment in the cathode cavity 2 CO in electrolyte 2 And water are reduced and converted into synthesis gas on the surface of the cathode catalytic electrode, a gas-liquid mixture enters a cathode gas-liquid separator for separation, and then is cooled to 30 ℃ by a cathode gas-phase cooler to obtain the synthesis gas, wherein H is 2 And CO (carbon monoxide) content of 86.7%, returning the cooled electrolyte to the cathode gas-liquid separator, separating, returning the cathode electrolyte to the gas-liquid mixer, and simultaneously, depleting CO in the anode cavity 2 Oxidizing and decomposing water in the electrolyte to generate oxygen, and cooling the generated mixed gas to 30 ℃ by an anode gas phase cooler to obtain oxygen, wherein O 2 The volume content reaches 91 percent, the cooling liquid returns to the anode gas-liquid separator, the separated anolyte also returns to the gas-liquid mixer to be mixed with the catholyte in concentration and pH value to obtain the lean CO 2 Electrolyte, a water replenishing pump is used for replenishing water to the anode gas-liquid separator, the water consumption is 127.4g/h, and the CO is poor in the gas-liquid mixer 2 The electrolyte has constant concentration all the time and can be recycled in a closed loop. The electrolytic pressure is controlled to be 0.5MPa through the air outlet pressure regulating valves on the cathode gas phase cooler and the anode gas phase cooler, and the absorption pressure is controlled to be 0.5MPa through the air outlet pressure regulating valve of the absorption tower.
Fig. 2 is a schematic diagram of the system of this embodiment, which includes three modules of carbon dioxide enrichment, electrolysis and electrolyte circulation, which correspond to the three steps of carbon dioxide enrichment, electrolysis and electrolyte circulation in the process flow diagram, respectively. The carbon dioxide enrichment module is used for concentrating CO 2 The gas source is used for absorption and comprises a fan, a buffer tank and an absorption tower, wherein the upstream of the absorption tower can be respectively filled with CO 2 The air source is connected with the anode circulating pump, the downstream is connected with the cathode circulating pump and the cathode cavity at the same time, and the fan is used for CO 2 The gas source is pressurized and sent into the absorption tower, the absorption pressure in the tower can be controlled by a pressure regulating valve at the gas outlet of the absorption tower, and the heat exchanger in the absorption tower can control the absorption temperature. Electrolytic module for generating CO 2 The electrochemical conversion synthesis gas comprises an electrochemical reactor and a control power supply, wherein the reactor consists of 1 group of cathode cavity/cation exchange membrane/anode cavity in series connectionBecome, the negative pole chamber upper reaches link to each other with the negative pole circulating pump, the absorption tower of electrolyte circulation module in proper order, and the low reaches link to each other with the negative pole vapour and liquid separator of electrolyte circulation module, negative pole gas phase cold area ware, the upper reaches in proper order of positive pole chamber links to each other with the positive pole circulating pump of electrolyte circulation module, liquid mixer, and the low reaches links to each other with the negative pole vapour and liquid separator of electrolyte circulation module, positive pole gas phase cold area ware in proper order, adjusts the electrolytic current through DC power supply, and the electrolysis temperature is through negative pole chamber and positive pole chamber entry electrolyte temperature regulation. The electrolyte circulating module is used for supplying electrolyte to the electrolysis unit, separating a gas-liquid mixture output by the electrolysis unit and mixing the electrolyte, and comprises an electrolyte conveying unit, a gas-liquid separation unit, a mixing unit and a water replenishing unit. The electrolyte delivery unit comprises an anode circulating pump, a relay pump and a cathode circulating pump, the upstream of the anode circulating pump is connected with the liquid mixer, the downstream of the anode circulating pump is respectively connected with the anode cavity, the upstream of the relay pump is connected with the gas-liquid mixer to lean CO 2 Feeding into the absorption tower from the liquid mixer, connecting with the absorption tower at the upstream of the cathode circulation pump, and introducing into the absorption tower 2 The electrolyte is fed into the cathode chamber. The gas-liquid separation unit comprises a cathode gas-liquid separator, a cathode gas-phase cooling tower, an anode gas-liquid separator and an anode gas-phase cooling tower, wherein the upstream of the cathode gas-liquid separator is connected with the cathode cavity, the downstream of the cathode gas-liquid separator is connected with the cathode gas-phase cooler to cool the gas phase to obtain synthesis gas, and cooling liquid returns to the cathode gas-liquid separator. The separated cathode electrolyte is converged into a liquid mixer, meanwhile, the upstream of the anode gas-liquid separator is connected with the anode cavity, the downstream of the anode gas-liquid separator is connected with an anode gas-phase cooler to cool the gas phase to obtain oxygen, cold shortage liquid returns to the anode gas-liquid separator, and the separated anode electrolyte is converged into the liquid mixer to be mixed with the anode electrolyte. The mixing unit is a liquid mixer, the upstream of the mixing unit is respectively connected with the cathode gas-liquid separator and the anode gas-liquid separator, and the downstream of the mixing unit is connected with the anode circulating pump. The electrolysis pressure is controlled by the pressure regulating valves of the gas outlet of the cathode gas-phase cooling zone device and the gas outlet of the anode gas-phase cooler. The water replenishing unit comprises a water replenishing pump and a water tank, wherein the upstream of the water replenishing pump is connected with the water tank, and the downstream of the water replenishing pump is connected with the anode gas-liquid separator and supplies reaction consumed water. The various process operating parameters are shown in table 1 below:
TABLE 1
Example 2
CO of the example 2 The process flow diagram and system schematic diagram of the synthesis gas production by electrolysis are the same as in example 1. The specific process operation flow comprises the following steps: 1.89Nm 3 CO of/h 2 The gas source (same as the gas source in the embodiment) is pressurized to 0.6MPa by a fan and then is sent into the absorption tower, the temperature of the absorption tower is controlled to be 60 ℃, the absorption pressure is controlled to be 0.5MPa, and meanwhile, the anode circulating pump is used for leading the lean CO in the liquid mixer to be 2 Electrolyte (KHCO) 3 Concentration of 1 mol/L) is sent into an absorption tower for enrichment to obtain CO-rich 2 Electrolyte, pH =8.3. The pressure of the electrolyte circulating system is adjusted to 0.1MPa through the pressure regulating valves at the air outlets of the cathode gas-phase cooler and the anode gas-phase cooler. The anode circulation pump also keeps the liquid mixer lean in CO 2 The electrolyte is fed into the anode cavity of the electrochemical reactor, and the absorption tower is rich in CO 2 The electrolyte is conveyed into the cathode cavity from a bypass pipeline between the absorption tower and the cathode cavity by relying on the pressure difference between the absorption tower and the cathode cavity, and a cathode circulating pump does not need to be started. Other process operations were the same as in example 1, and H in the syngas obtained 2 And CO content up to 83.3% by volume, O in the obtained oxygen 2 The volume content reaches 83.3 percent. And (4) supplementing water for the anode gas-liquid separator by a water supplementing pump for 148L/h. The process operating parameters are shown in table 2 below:
TABLE 2
Example 3
CO of the example 2 The flow chart of the synthesis gas production process by electrolysis is the same as that of example 1, and the system schematic diagram is shown in FIG. 3. Detailed technical exerciseThe working process comprises the following steps: 182L/h of CO 2 Gas source (from low temperature methanol wash product gas (CO) 2 99.8% by volume of H 2 The concentration of S is 32ppm and the pressure is 0.22 MPa), the S is introduced into a desulfurizing tower to treat H in a gas source 2 Fe in S-quilt desulfurizing tower 2 O 3 Desulfurization of calcium magnesium aluminosilicate clay catalysts to H 2 After the concentration of S is reduced to 10ppm, introducing the mixture into an absorption tower for enrichment, controlling the temperature of the absorption tower to be 60 ℃, controlling the absorption pressure to be 0.1MPa through a pressure regulating valve at an air outlet of the absorption tower, and controlling the unabsorbed part of CO 2 And tail gas is sent into the absorption tower from the tower top through a fan for circulating absorption. Simultaneously, an anode circulating pump is used for leading the lean CO in the mixing tank to be lean 2 Electrolyte (KHCO) 3 Concentration of 1 mol/L) is sent into an absorption tower for enrichment to obtain CO-rich gas at 60 DEG C 2 Electrolyte is pumped into the cathode cavity by a cathode circulating pump, and the anode circulating pump also pumps the CO poor at 60 ℃ in the liquid mixer 2 The electrolyte is fed into the anode chamber. The electrolysis was carried out with the electrolysis current controlled at 600A. Cooling to 30 deg.C by cathode gas phase cooler to obtain synthesis gas, wherein H 2 And CO is up to 82.7%, the cooled electrolyte is returned to the cathode gas-liquid separator, the separated cathode electrolyte is returned to the mixing tank, and meanwhile, the cathode electrolyte is cooled to 30 ℃ by the anode gas-phase cooler to obtain oxygen, wherein O is 2 The volume content reaches 89.3 percent, the cooling liquid returns to the anode gas-liquid separator, the separated anolyte also returns to the mixing tank to be mixed with the catholyte in concentration and pH value to obtain the lean CO 2 And electrolyte is replenished to the mixing tank by a water replenishing pump at the same time, wherein 139g/h of water is replenished to the mixing tank. The pressure of the air outlet pressure regulating valves on the cathode gas-phase cooler and the anode gas-phase cooler is controlled to be 0.1MPa.
The system comprises three modules of carbon dioxide enrichment, electrolysis and electrolyte circulation, which respectively correspond to the three steps of carbon dioxide enrichment, electrolysis and electrolyte circulation in the process flow diagram. The carbon dioxide enrichment module is used for enriching CO 2 The gas source is used for removing impurities and absorbing and comprises a desulfurizing tower, an absorbing tower, a front buffer tank, a fan, a rear buffer tank, a desulfurizing tower upstream and CO 2 The gas source is connected, the downstream is connected with the absorption tower, the gas outlet of the absorption tower is connected with the front buffer tank, the fan and the rear buffer tank, and the rear buffer tank is connected with the inlet of the absorption tower to formCO 2 Tail gas is circularly absorbed for energy supply, and the downstream of the absorption tower is also connected with an anode circulating pump and is input with lean CO 2 The electrolyte is absorbed, the absorption pressure in the tower can be controlled by a pressure regulating valve at an air outlet of the tower, and the absorption temperature can be controlled by a heat exchanger in the absorption tower. The electrolyte circulation module is used for supplying electrolyte to the electrolysis unit, separating a gas-liquid mixture output by the electrolysis unit and mixing the electrolyte, and comprises an electrolyte conveying unit, a gas-liquid separation unit, a mixing unit and a water replenishing unit. The electrolyte conveying unit comprises an anode circulating pump and a cathode circulating pump, the anode circulating pump is connected with the absorption tower at the downstream and is also connected with the anode cavity to feed lean CO 2 Electrolyte, the upstream of the cathode circulating pump is connected with the absorption tower to enrich CO 2 The electrolyte is fed into the cathode chamber. The gas-liquid separation unit comprises a cathode gas-liquid separator, a cathode gas-phase cooling tower, an anode gas-liquid separator and an anode gas-phase cooling tower, the mixing unit comprises a mixing tank, the upstream of the cathode gas-liquid separator is connected with a cathode cavity, the downstream of the cathode gas-liquid separator cools gas phase to obtain synthetic gas, cooling liquid returns to the cathode gas-liquid separator, catholyte separated by the cathode gas-liquid separator converges into the mixing tank, meanwhile, the upstream of the anode gas-liquid separator is connected with the anode cavity, the downstream of the anode gas-liquid separator is connected with the anode gas-phase cooler to obtain oxygen, cold liquid is returned to the anode gas-liquid separator, and separated anolyte converges into the mixing tank to be mixed. The pressure of the electrolyte circulating system, namely the pressure of the cathode side or the anode side, is controlled to be 0.1MPa through the air outlets of the cathode gas-phase cooler and the anode gas-phase cooler. The water replenishing unit comprises a water replenishing pump and a water tank, wherein the upstream of the water replenishing pump is connected with the water tank, and the downstream of the water replenishing pump is connected with the mixing tank to supply reaction consumed water. The electrolytic module composition and connection mode were the same as in the examples. The process operating parameters are shown in table 3 below:
TABLE 3
Example 4
CO of the example 2 The process flow diagram and the system schematic diagram of the synthesis gas production by electrolysis are respectively shown in the figure 4 and the figure 5.The process flow of this example differs from example 3 in that a syngas purification step is added downstream of the back end of the electrolyte circulation step, and the syngas obtained after cooling the cathode gas phase cooler in the electrolyte circulation step is further decarbonized and purified to obtain a syngas product, and the separated CO is used as a CO product 2 And absorbing tower top CO in the step of enriching carbon dioxide 2 The tail gas is combined and pumped into an absorption tower by a circulating fan in the carbon dioxide enrichment step at the flow rate of 65.4L/h for cyclic absorption and reuse. This step absorbs CO discharged from the top of the column 2 CO separated in tail gas and synthesis gas purification and decarbonization step 2 The gas is recycled, and the CO can be greatly reduced 2 The air inflow of the air source is improved, and CO is increased 2 The utilization ratio of (2).
The difference between the system of this embodiment and embodiment 3 is that a pressure swing adsorption device is added downstream of the cathode gas phase cooler of the electrolyte circulation module, and the synthesis gas is further decarbonized to obtain a synthesis gas product. Separated CO 2 The gas enters a carbon dioxide enrichment module CO 2 And the circulating unit is pressurized by a circulating fan and then sent into the absorption tower for circulating absorption. The process operating parameters are shown in table 4 below:
TABLE 4
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.
Claims (10)
1. CO (carbon monoxide) 2 The electrolysis synthesis gas preparation process is characterized by comprising the following steps:
carbon dioxide enrichmentStep (d) of using lean CO 2 Electrolyte from CO 2 Absorption of CO in a gas source 2 Obtaining CO-rich 2 An electrolyte;
an electrolyte circulation step of circulating the CO-rich 2 Electrolyte is fed into the cathode chamber of an electrochemical reactor while said CO is depleted 2 Electrolyte is fed into the anode chamber of the electrochemical reactor, catholyte discharged from the cathode chamber after electrolysis and anolyte discharged from the anode chamber are mixed and supplemented with water to obtain CO-lean solution with constant concentration 2 An electrolyte; and
an electrolysis step of supplying direct current to the electrochemical reactor, the CO-rich being in a cathode chamber of the electrochemical reactor 2 CO in electrolyte 2 And water is catalytically reduced to synthesis gas while the CO is depleted in the anode chamber of the electrochemical reactor 2 The water in the electrolyte is catalytically oxidized to oxygen.
2. CO according to claim 1 2 The process for preparing the synthesis gas by electrolysis is characterized in that the absorption pressure in the carbon dioxide enrichment step is 10kPa-5MPa, and the absorption temperature is 5-90 ℃; the electrolysis temperature of the electrochemical reactor is 5-90 ℃, and the electrolysis pressure is 10kPa-5MPa.
3. CO according to claim 1 2 Process for the production of synthesis gas by electrolysis, characterized in that said lean CO is 2 The electrolyte is an alkaline electrolyte, preferably an alkali metal bicarbonate or carbonate electrolyte; the alkali metal is one or more of lithium, sodium, potassium, rubidium and cesium, preferably potassium and sodium, and the concentration of the metal ions in the electrolyte is 0.05-6mol/L.
4. CO according to claim 1 2 Process for the production of synthesis gas by electrolysis, characterised in that said CO-rich product is obtained 2 The pH value of the electrolyte is 6-11.
5. CO according to claim 1 2 Process for the production of synthesis gas by electrolysis, characterized in that said CO is 2 CO in the gas source 2 The volume content is more than or equal to 3 percent.
6. CO according to claim 1 2 The process for preparing synthesis gas by electrolysis is characterized in that CO is absorbed 2 Before, the method also comprises the step of treating the CO 2 Removing impurities from gas source to remove CO 2 Particulate matter in the gas source and gases detrimental to the electrochemical reactor.
7. CO according to claim 1 2 Process for the production of synthesis gas by electrolysis, characterized in that said enrichment module pressure is equal or not equal to the electrolysis pressure, preferably equal.
8. CO (carbon monoxide) 2 An electrolysis synthesis gas production system, comprising:
carbon dioxide enrichment module for using lean CO 2 Electrolyte from CO 2 Absorption of CO in a gas source 2 Obtaining CO-rich 2 An electrolyte;
an electrolysis module comprising an electrochemical reactor, the CO-rich in a cathode chamber of the electrochemical reactor 2 CO in electrolyte 2 And water is catalytically reduced to syngas while the CO is depleted in the anode chamber of the electrochemical reactor 2 The water in the electrolyte is catalytically oxidized into oxygen; and
an electrolyte circulation module for supplying the electrolysis module with the CO-rich gas 2 Electrolyte and the CO lean 2 Electrolyte, and mixing and replenishing the electrolyte discharged from the cathode and the anode of the electrolysis module to obtain CO-poor electrolyte with constant concentration 2 And (3) an electrolyte.
9. CO according to claim 8 2 The system for preparing the synthesis gas by electrolysis is characterized in that the system can be under a pressure equalizing working condition, namely the electrolysis pressure is equal to the absorption pressure of the carbon dioxide enrichment module; the pressure can also be under non-pressure equalizing working condition, namely the electrolysis pressure is not equal to the absorption pressure of the carbon dioxide enrichment module; pressure equalization conditions are preferred.
10. CO according to claim 8 2 The system for producing the synthesis gas through electrolysis is characterized in that the carbon dioxide enrichment module further comprises an impurity removal unit, and the impurity removal unit is used for removing the CO 2 Particulate matter in the gas source and gases detrimental to the electrochemical reactor.
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| CN202211066184.2A CN115369425A (en) | 2022-09-01 | 2022-09-01 | Flue gas CO 2 Process and system for preparing synthesis gas by electrolysis |
| PCT/CN2023/095474 WO2024045700A1 (en) | 2022-09-01 | 2023-05-22 | Process and system for preparing synthesis gas by electrolysis of co2 in flue gas |
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| CN115672020A (en) * | 2022-12-12 | 2023-02-03 | 中国科学院西北生态环境资源研究院 | Device for capturing, separating and catalyzing carbon dioxide in flue waste gas and control method thereof |
| WO2024045700A1 (en) * | 2022-09-01 | 2024-03-07 | 碳能科技（北京）有限公司 | Process and system for preparing synthesis gas by electrolysis of co2 in flue gas |
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| US20140151240A1 (en) * | 2012-11-30 | 2014-06-05 | Alstom Technology Ltd | Electroylytic reduction of carbon capture solutions |
| CN216947223U (en) * | 2022-01-18 | 2022-07-12 | 南亚塑胶工业股份有限公司 | Carbon dioxide electrolysis device |
| CN115369425A (en) * | 2022-09-01 | 2022-11-22 | 碳能科技（北京）有限公司 | Flue gas CO 2 Process and system for preparing synthesis gas by electrolysis |
| CN115970448A (en) * | 2023-02-09 | 2023-04-18 | 中海石油气电集团有限责任公司 | Flue gas CO 2 Carbon-loading method and system integrating trapping and electrolysis |
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| WO2024045700A1 (en) * | 2022-09-01 | 2024-03-07 | 碳能科技（北京）有限公司 | Process and system for preparing synthesis gas by electrolysis of co2 in flue gas |
| CN115672020A (en) * | 2022-12-12 | 2023-02-03 | 中国科学院西北生态环境资源研究院 | Device for capturing, separating and catalyzing carbon dioxide in flue waste gas and control method thereof |
| CN115672020B (en) * | 2022-12-12 | 2023-02-28 | 中国科学院西北生态环境资源研究院 | Device for capturing, separating and catalyzing carbon dioxide in flue waste gas and control method thereof |
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