Device and method for producing hydrogen and carbon monoxide step by step through chemical looping

Abstract

The invention provides a device and method for preparing hydrogen and carbon monoxide step by step through chemical looping, and relates to the technical field of energy conversion, and the device comprises a fuel reactor, a carbon dioxide oxidation reactor and an air reactor; the fuel reactor is provided with an oxygen carrier and absorbent inlet, a fuel inlet and a water vapor inlet, and is used for a reduction reaction of a hydrocarbon fuel and water vapor mixed gas and an oxygen carrier and an absorption reaction of an absorbent on carbon dioxide; a preset reaction temperature is set in the carbon dioxide oxidation reactor, so that the absorbent after absorbing the carbon dioxide is desorbed, the carbon dioxide is released, and the generated carbon dioxide reacts with the reduced oxygen carrier; air is introduced into a second inlet of the air reactor and used for completely oxidizing the oxygen carrier, and the completely oxidized oxygen carrier and the desorbed absorbent are lifted and then introduced into the fuel reactor to participate in the next circulation. According to the invention, the conversion rate of hydrocarbon fuel and the yield of hydrogen are improved, and step-by-step preparation of high-concentration hydrogen and carbon monoxide is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of energy conversion, and in particular to a device and method for producing hydrogen and carbon monoxide by chemical chain step-by-step production. Background Art

[0002] Using natural gas to produce hydrogen and recycle the generated CO2 has become a frontier in clean energy conversion. At present, natural gas wet reforming is still the main way to produce hydrogen in the world, but the product after the reforming reaction is a mixed gas mainly composed of H2. It is necessary to further convert carbon monoxide into carbon dioxide through water gas shift and produce high-concentration hydrogen through pressure swing adsorption. Compared with traditional natural gas hydrogen production, there are problems such as high energy consumption, high carbon emissions, and complex systems. Natural gas chemical chain hydrogen production uses step-by-step reactions of oxygen carriers in different reactors to achieve high-concentration H2 production and efficient CO2 capture.

[0003] Although methane chemical chain hydrogen production can achieve the step-by-step production and capture of CO2 and H2, there are two processes of partial oxidation and complete oxidation of methane during the reduction reaction. In order to increase the proportion of complete oxidation and thus achieve complete decarbonization of methane, excess oxygen carriers are often required, resulting in a significant decrease in the overall unit methane hydrogen production of the system. In addition, the large amount of CO2 captured during the oxygen carrier reduction reaction also faces problems such as storage, transportation and high-value utilization. Summary of the invention

[0004] In view of this, the embodiments of the present application provide a chemical chain step-by-step production device and method for hydrogen and carbon monoxide, which does not require additional CO2 capture and reuse, and achieves efficient conversion and utilization of CO2 while producing high-concentration hydrogen, while reducing carbon emissions and lowering energy consumption for hydrogen production.

[0005] The embodiment of the present application provides the following technical solution: a chemical chain step-by-step hydrogen and carbon monoxide production device, comprising: a fuel reactor, a carbon dioxide oxidation reactor and an air reactor;

[0006] The fuel reactor is respectively provided with an oxygen carrier and an absorbent inlet, a water vapor inlet, and a fuel inlet for introducing hydrocarbon fuel, which are used for the oxidation-reduction reaction of the hydrocarbon fuel and water vapor mixed gas with the oxygen carrier, and the absorption reaction of carbon dioxide by the absorbent. The first outlet of the fuel reactor is used to discharge the reaction product hydrogen. The second outlet of the fuel reactor is connected to the inlet of the carbon dioxide oxidation reactor, and is used to introduce the reduced oxygen carrier after being reduced and the absorbent after absorbing carbon dioxide into the carbon dioxide oxidation reactor.

[0007] The carbon dioxide oxidation reactor is preset with a set reaction temperature, so that the absorbent after absorbing carbon dioxide desorbs in the carbon dioxide oxidation reactor and releases carbon dioxide, and the generated carbon dioxide oxidizes the reduced oxygen carrier, the first outlet of the carbon dioxide oxidation reactor is used to discharge the reaction product carbon monoxide gas, and the second outlet of the carbon dioxide oxidation reactor is connected to the first inlet of the air reactor, so as to introduce the partially oxidized oxygen carrier and the desorbed absorbent into the air reactor;

[0008] Air is introduced into the second inlet of the air reactor to completely oxidize the partially oxidized oxygen carrier and to lift the completely oxidized oxygen carrier and the desorbed absorbent. The outlet of the air reactor is connected to the oxygen carrier and absorbent inlet of the fuel reactor to introduce the oxygen carrier and absorbent into the fuel reactor to participate in the next cycle.

[0009] According to one embodiment of the present application, a cooling and separation device is further included, wherein the inlet of the cooling and separation device is connected to the first outlet of the fuel reactor, and is used to cool and separate the product gas of the fuel reactor to obtain high-concentration hydrogen.

[0010] According to one embodiment of the present application, a cyclone separator is further included. The cyclone separator is arranged at the outlet of the air reactor and is used for gas-solid separation to separate mixed solid particles of the oxygen carrier and the absorbent from the high-temperature air.

[0011] According to one embodiment of the present application, the heat released in the air reactor is transferred to the fuel reactor in the form of sensible heat of the oxygen carrier, and the high-temperature air separated by the cyclone separator can further supply heat to other reactors to achieve heat recovery.

[0012] According to one embodiment of the present application, the fuel reactor and the carbon dioxide oxidation reactor are moving bed reactors, and the air reactor is a fast bed reactor.

[0013] According to one embodiment of the present application, a plurality of baffles are respectively provided in the fuel reactor and the carbon dioxide oxidation reactor, a plurality of circular holes are evenly opened on the baffles, the plurality of baffles are respectively inclined at set angles, and the inclination directions of adjacent baffles are opposite.

[0014] According to one embodiment of the present application, the oxygen carrier is a metal oxide oxygen carrier that can reduce CO2 to CO, any one of an iron-based oxygen carrier and a perovskite.

[0015] According to an embodiment of the present application, the absorbent is any one of spherical lithium silicate, lithium zirconate, and calcium oxide absorbent particles.

[0016] According to one embodiment of the present application, it also includes a feeding device, which is connected to the air reactor and is used to add oxygen carriers and absorbents.

[0017] According to one embodiment of the present application, it also includes an air intake preheating device, and the fuel inlet and the water vapor inlet of the fuel reactor and the second inlet of the air reactor are respectively provided with the air intake preheating device.

[0018] The present application also provides a method for producing the above-mentioned chemical chaining step-by-step hydrogen and carbon monoxide production device, comprising:

[0019] The oxygen carrier and absorbent are introduced through the oxygen carrier and absorbent inlet of the fuel reactor, the hydrocarbon fuel is introduced through the fuel inlet of the fuel reactor, and the water vapor is introduced through the water vapor inlet of the fuel reactor, so that the hydrocarbon fuel and the water vapor are mixed and then undergo a reduction reaction with the oxygen carrier to produce a reduced oxygen carrier and carbon monoxide, carbon dioxide and hydrogen, the carbon dioxide in the fuel reactor is absorbed by the absorbent, and the carbon monoxide and water vapor are prompted to continue to react to produce hydrogen, and the produced hydrogen is discharged and collected;

[0020] Introducing a reduced oxygen carrier and an absorbent for absorbing carbon dioxide into the carbon dioxide oxidation reactor, presetting a set reaction temperature in the carbon dioxide oxidation reactor, desorbing the CO2 absorbent and oxidizing the oxygen carrier in situ, so that the absorbent after absorbing carbon dioxide desorbs in the carbon dioxide oxidation reactor to release carbon dioxide, and oxidizing the reduced oxygen carrier in situ to generate carbon monoxide, and the generated carbon monoxide is discharged and collected;

[0021] The partially oxidized oxygen carrier and the desorbed absorbent are introduced into the air reactor, and preheated air is introduced into the air reactor to completely oxidize the partially oxidized oxygen carrier. The completely oxidized oxygen carrier and the desorbed absorbent are lifted and introduced into the fuel reactor to participate in the next cycle.

[0022] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0023] 1. In the embodiment of the present invention, a mixture of methane and water vapor is continuously introduced into the fuel reactor during the hydrogen production stage, and the carbon dioxide generated by the reaction of the oxygen carrier and the fuel gas is absorbed by the absorbent to continuously reduce the water gas shift reaction. The concentration of carbon dioxide in the gas breaks the chemical equilibrium in the hydrogen production system, causing the reaction to move toward producing more hydrogen, thereby increasing the conversion rate of methane and the yield of hydrogen. In addition, the addition of the absorbent changes the equilibrium conditions of the reaction system, allowing the reaction of the entire hydrogen production system to proceed at a relatively low temperature.

[0024] 2. In the embodiment of the present invention, carbon dioxide is absorbed and fixed by the absorbent in the reactor during the fuel hydrogen production stage, and then carbon monoxide gas is produced while the oxygen carrier is oxidized by the carbon dioxide produced by desorption of the absorbent in the second reaction stage. Compared with the traditional chemical chain hydrogen production, the absorption and utilization of carbon dioxide produced in the fuel reactor is realized, which not only reduces the emission of greenhouse gas carbon dioxide, but also obtains high-quality carbon monoxide gas. The obtained carbon monoxide can be used as chemical raw materials or directly burned for heating, power generation, etc.

[0025] 3. In the embodiment of the present invention, an absorbent is added during the hydrogen production stage, which not only promotes the conversion of carbon monoxide into carbon dioxide and hydrogen, but also absorbs the product carbon dioxide, thereby obtaining a single product gas, hydrogen, in the fuel reactor; in the second stage of the reaction, the reaction of ferrous oxide with carbon dioxide is utilized to consume the carbon dioxide stored in the absorbent and obtain a single product gas, carbon monoxide; in the complete oxidation stage of the oxygen carrier, oxygen in the air is used to oxidize and regenerate the oxygen carrier, and air is used as a carrier gas to complete the lifting process of the oxygen carrier and the absorbent particles; through the entire reaction process, the single gases hydrogen and carbon monoxide are prepared step by step, avoiding the separation and purification of multiple product gases.

[0026] 4. The entire reaction is carried out in a moving bed. Under the action of gravity and carrier gas lifting force, the oxygen carrier and absorbent particles circulate, allowing the reaction system to continuously produce product gas. At the same time, the heat released in the air reactor is transferred to the fuel reactor in the form of sensible heat of the oxygen carrier, realizing the coupling of multiple processes and improving the overall performance of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a structural block diagram of the preparation process of an embodiment of the present invention;

[0029] Figure 2 1 is a schematic diagram of the structure of a preparation device according to an embodiment of the present invention;

[0030] Among them, 1-air reactor, 2-feeding equipment, 3-iron-based oxygen carrier particles, 4-carbon dioxide absorbent particles, 5-cyclone separator, 6-condenser, 7-fuel reactor, 8-carbon dioxide oxidation reactor, 9, 10, 11-intake air preheating device, 12-baffle, 13, 14-heat conduction device. DETAILED DESCRIPTION

[0031] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0032] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0033] The present invention provides a process for completing the production of hydrogen and carbon monoxide from methane chemical chain by cyclic regeneration of absorbent and oxygen carrier in a moving bed system. The reaction flow chart is shown in the following figure. Figure 1 As shown, an embodiment of the present invention provides a chemical chain step-by-step hydrogen and carbon monoxide production device, comprising: a fuel reactor, a carbon dioxide oxidation reactor and an air reactor;

[0034] The fuel reactor is respectively provided with an oxygen carrier and an absorbent inlet, a water vapor inlet, and a fuel inlet for introducing hydrocarbon fuel, which are used for the oxidation-reduction reaction of the mixed gas of hydrocarbon fuel and water vapor with the oxygen carrier, and the absorption reaction of carbon dioxide by the absorbent. The first outlet of the fuel reactor is used to discharge the reaction product hydrogen. The second outlet of the fuel reactor is connected to the inlet of the carbon dioxide oxidation reactor, and is used to introduce the reduced oxygen carrier after reduction and the absorbent after absorbing carbon dioxide into the carbon dioxide oxidation reactor.

[0035] The carbon dioxide oxidation reactor is preset with a set reaction temperature, so that the absorbent after absorbing carbon dioxide undergoes a desorption reaction in the carbon dioxide oxidation reactor to release carbon dioxide, and the generated carbon dioxide oxidizes the reduced oxygen carrier. The first outlet of the carbon dioxide oxidation reactor is used to discharge the reaction product carbon monoxide gas, and the second outlet of the carbon dioxide oxidation reactor is connected to the first inlet of the air reactor, so as to introduce the partially oxidized oxygen carrier and the desorbed absorbent into the air reactor;

[0036] Air is introduced into the second inlet of the air reactor to completely oxidize the partially oxidized oxygen carrier and to lift the completely oxidized oxygen carrier and the desorbed absorbent. The outlet of the air reactor is connected to the oxygen carrier and absorbent inlet of the fuel reactor to introduce the oxygen carrier and absorbent into the fuel reactor to participate in the next cycle.

[0037] In the fuel reactor in the embodiment of the present invention, methane and water vapor are the intake air of the fuel reactor. They are preheated by a preheater and then fed into the reactor from the bottom, flowing in the opposite direction to the solid oxygen carrier and absorbent particles. The introduced methane and water vapor are mixed and reacted with the oxidized iron-based oxygen carrier. During the reaction, the oxygen carrier will be converted into reduced ferrous oxide, and the methane water vapor will be converted into carbon monoxide, carbon dioxide and hydrogen. At the same time, the spherical absorbent in the fuel reactor will absorb the carbon dioxide produced in the reaction, promoting the conversion of carbon monoxide into more hydrogen through the water-gas shift reaction, thereby obtaining high-concentration hydrogen. The produced hydrogen is discharged from the upper part of the fuel reactor and then collected and stored. After passing through the fuel reactor, the absorbent fixed with carbon dioxide and the reduced oxygen carrier will enter the carbon dioxide oxidation reactor. At a specific preset temperature, the spherical absorbent will desorb and release carbon dioxide, and the generated carbon dioxide will be released. Carbon will react with reduced ferrous oxide to obtain carbon monoxide gas and ferrosoferric oxide. As the reaction proceeds and carbon dioxide is consumed, the desorption and regeneration of the absorbent will be promoted in turn. After passing through the carbon dioxide oxidation reactor, part of the oxidized oxygen carrier and the desorbed absorbent enter the air reactor, and the spherical absorbent and oxygen carrier are lifted by the air. At the same time, the oxygen in the air oxidizes and regenerates the oxygen carrier, thereby promoting the continued reaction. After leaving the air reactor, the oxygen carrier and absorbent particles lifted by the air will enter the cyclone separator, where the air and solid particles are separated, the air is discharged, and the absorbent and oxygen carrier will enter the fuel reactor to continue the next cycle.

[0038] The embodiment of the present invention realizes the absorption of the product carbon dioxide by means of the carbon dioxide absorbent, promotes the forward progress of the reduction reaction, that is, promotes the transfer of CO and H2O to CO2 and H2. The absorbent in the fuel reactor absorbs the generated CO2, improves the hydrogen yield, realizes the absorption and capture of CO2, improves the conversion rate of fuel gas, and can reduce the reduction reaction temperature to a certain extent. The embodiment of the present invention utilizes the absorption enhancement effect of the carbon dioxide absorbent to enhance the water gas shift reaction in the reduction reaction process, thereby promoting the conversion of carbon monoxide to hydrogen, and improving the hydrogen production and hydrogen purity. The embodiment of the present invention combines the chemical chain with the absorption and release of carbon dioxide. The desorbed CO2 is used in the carbon dioxide oxidation reactor to oxidize the oxygen carrier, realize the conversion and utilization of CO2, and produce high-value CO gas, realize the absorption and utilization of carbon dioxide in different reaction processes, and the system can continuously produce two high-quality gases at the same time.

[0039] During specific implementation, the oxygen carrier in the embodiment of the present invention has a variety of oxidation states, such as iron-based oxygen carriers, perovskites, etc., and the absorbent is selected from absorbent particles such as lithium silicate, lithium zirconate, and calcium oxide. The oxygen carrier and absorbent made into spherical particles circulate in the moving bed. In this embodiment, the absorbent is selected from lithium silicate, and the absorbent can also be replaced with other materials with higher carbon dioxide absorption / desorption performance and high cycle characteristics. In this embodiment, the oxidized oxygen carrier is iron oxide and the reduced oxygen carrier is ferrous oxide. In order for the oxygen carrier to have better reaction activity, an inert support material can also be added to the oxygen carrier, or other composite materials containing iron can be selected.

[0040] In order to obtain high-quality hydrogen, in one embodiment, a cooling and separation device is further included, wherein the inlet of the cooling and separation device is connected to the first outlet of the fuel reactor, and is used to cool and separate the product gas of the fuel reactor to obtain high-concentration hydrogen.

[0041] In one embodiment, a cyclone separator is further included. The cyclone separator is arranged at the outlet of the air reactor and is used for gas-solid separation to separate mixed solid particles of the oxygen carrier and the absorbent from the high-temperature air.

[0042] The heat released in the air reactor is transferred to the fuel reactor in the form of sensible heat of the oxygen carrier, and the high-temperature air separated by the cyclone separator can be further used to supply heat to other reactors through a heat conduction device to achieve heat recovery.

[0043] The embodiment of the present invention realizes the recycling of heat energy through the circulation of oxygen carriers and absorbents and the coupling between different processes. The third stage of the reaction process is the complete oxidation of the oxygen carrier by air. A large amount of heat will be released during the reaction of oxygen and oxygen carrier, which will increase the bed temperature of the oxygen carrier and absorbent, and at the same time, a relatively high temperature tail gas will be discharged. After passing through the air reactor, the high-temperature oxygen carrier and absorbent particles that have just been oxidized and regenerated will flow into the fuel reactor, and react with methane and water vapor in the fuel reactor to produce hydrogen. At the same time, the high-temperature tail gas generated by the air reactor can also be used to heat the fuel reactor and the carbon dioxide oxidation reactor, thereby improving the conversion rate of methane in the first reaction stage and promoting the absorbent to desorb more carbon dioxide in the second stage.

[0044] In one embodiment, a plurality of baffles are respectively provided in the fuel reactor and the carbon dioxide oxidation reactor, a plurality of circular holes are evenly provided on the baffles, the plurality of baffles are respectively inclined at set angles, and the inclination directions of adjacent baffles are opposite.

[0045] In one embodiment, a feeding device is further included, wherein the feeding device is connected to the air reactor and is used for adding oxygen carriers and absorbents.

[0046] In one embodiment, it further includes an air intake preheating device, and the fuel inlet and the water vapor inlet of the fuel reactor and the second inlet of the air reactor are respectively provided with the air intake preheating device.

[0047] like Figure 2 As shown, an embodiment of the present invention provides a device for producing hydrogen and carbon monoxide by chemical chain step-by-step, which mainly includes: a fuel reactor 7, a carbon dioxide oxidation reactor 8, an air reactor 1, a cyclone separator 5, a condenser 6, an air intake preheating device 9, 10, 11, and carbon dioxide absorbent particles 4 and iron-based oxygen carrier particles 3. Under the action of gravity and lifting gas, the spherical absorbent and oxygen carrier pass through the fuel reactor 7, the carbon dioxide oxidation reactor 8 and the oxygen carrier air reactor 1 in sequence and complete a cycle. At the same time, the hydrogen produced in the fuel reactor 7 and the carbon monoxide produced in the carbon dioxide oxidation reactor 8 are discharged from the top of the reactor and collected and stored. The whole cycle process mainly includes the following three stages:

[0048] The first stage is the reduction process of the oxygen carrier, and hydrogen is generated in the fuel reactor 7. First, the methane that has passed through the air preheating device 9 and the water vapor that has passed through the air preheating device 10 will flow into the bottom of the fuel reactor 7 after mixing, and at the same time, the oxidized iron-based oxygen carrier particles 3 and the carbon dioxide absorbent particles 4 will enter from the top of the fuel reactor 7, and the reaction gas and solid particles will flow in reverse, so that the reaction gas methane and water vapor can fully contact and react with the oxygen carrier and absorbent. In this stage, the reduction reaction of the oxygen carrier will occur, and the oxidized ferric oxide will react with methane to produce carbon monoxide and hydrogen. At the same time, the oxidized iron-based oxygen carrier will be reduced to ferrous oxide. In addition, the generated carbon monoxide will react with water vapor to produce carbon dioxide and hydrogen. The lithium silicate absorbent flowing in with the oxygen carrier will absorb the generated carbon dioxide in situ. According to the equilibrium principle of chemical reactions, the reduction of carbon dioxide in the reaction system will inevitably promote the water gas shift reaction to move toward the direction of producing carbon dioxide and hydrogen, thereby increasing the yield of hydrogen. Finally, the gas discharged from the fuel reactor 7 contains a small amount of water vapor in addition to hydrogen, and high-concentration hydrogen can be obtained by simple cooling through the condenser 6. Since the addition of the absorbent changes the equilibrium conditions of the reaction system, the reaction of the entire hydrogen production system can be carried out at a lower temperature.

[0049] The second stage is the process of producing carbon monoxide, and the oxygen carrier in the reduced state will be oxidized by carbon dioxide. After the reaction in the first stage, the oxygen carrier becomes the ferrous oxide in the reduced state and enters the carbon dioxide oxidation reactor 8 together with the saturated absorbent fixed with carbon dioxide. At this time, under the preset temperature conditions, the absorbent in the carbon dioxide oxidation reactor 8 desorbs and releases carbon dioxide, and the released carbon dioxide reacts with the reduced oxygen carrier (ferrous oxide) inside the reactor to generate carbon monoxide, and the ferrous oxide is oxidized to ferroferric oxide. The ferrous oxide continuously consumes the released carbon dioxide and in turn further promotes the desorption regeneration of the absorbent, and the carbon monoxide produced in the second stage is discharged and collected from the top of the reactor.

[0050] The third stage is the oxidation stage of the oxygen carrier, and the lifting process of the oxygen carrier and absorbent particles is completed at the same time. After the reaction in the second stage, the reduced ferrous oxide is oxidized by carbon dioxide to ferroferric oxide, and then enters the air reactor 1. The air is preheated by the air intake preheating device 11 and fed into the bottom of the air reactor 1. The oxygen carrier and absorbent particles are slowly lifted to the top of the air reactor 1 under the action of the bottom air, and the oxygen completely oxidizes the oxygen carrier during the lifting process. After passing through the air reactor 1, the oxygen carrier is oxidized and recycled, and the oxidized oxygen carrier and absorbent particles enter the cyclone separator 5 together with the air, and the gas-solid separation is completed in the cyclone separator 5. The separated air is discharged from the top, and the separated solid flows from the bottom into the fuel reactor 7 for the next cycle.

[0051] In the circulation process of the whole moving bed, the coupling of multiple processes and the recycling of heat are also realized. The oxidation process of the oxygen carrier by air in the air reactor 1 is an exothermic reaction, and the heat released in the reaction process will be absorbed by the oxygen carrier and air. After the whole lifting process, the high-temperature tail gas and solid particles flow into the cyclone separator 5 together, and the high-temperature gas separated from the cyclone separator 5 is used to supply heat to the fuel reactor 7 and the carbon dioxide oxidation reactor 8 through the heat conduction device 13, 14, thereby realizing the recycling of system heat. In addition, a baffle 12 with micropores is also arranged in the fuel reactor 7 and the carbon dioxide oxidation reactor 8, and the baffle 12 is tilted so that the iron-based oxygen carrier and absorbent particles participating in the reaction flow slowly under the action of gravity, thereby ensuring the residence time of the reactants in the reactor, and then improving the conversion rate of the reactants. Since the oxygen carrier and absorbent particles are constantly circulating in the whole moving bed system, there must be a certain degree of wear and tear, so a feeding device 2 is also provided in the air reactor of the whole system to complete the replenishment of the oxygen carrier and absorbent particles.

[0052] The device of the embodiment of the present invention is specifically a moving bed reactor, and the flow of oxygen carrier and absorbent particles in the reactor is mainly divided into three stages: the first is the descending stage, which needs to pass through the fuel reactor and the carbon dioxide oxidation reactor in turn. The two reactors are arranged with baffles with a porous structure, and the baffles with small holes are placed obliquely. The spherical solid will be subject to a tiny reaction gas lift, and at the same time, it will slowly move downward along the baffle under the action of gravity, fully ensuring the residence time in the reactor; the second stage is the ascending stage, and the oxygen carrier and absorbent particles coming out of the carbon dioxide oxidation reactor will flow into the air reactor, and the air reactor is arranged with air lifting gas from bottom to top, and the solid particles at the bottom are lifted to the top of the entire reaction device by air; finally, the air and solid particles at the top flow into the cyclone separator together, and the gas-solid separation is completed in the cyclone separator, and the air is discharged from the upper part of the separator, and the mixed particles of the oxygen carrier and the absorbent flow into the fuel reactor and complete the cycle. Utilizing the flow characteristics of the moving bed reactor, the uninterrupted operation of the multi-step reaction in the chemical chain can be realized, the continuous production of the reaction product can be realized, and the efficiency of the entire reaction device is improved.

[0053] In the fuel reactor described in the embodiment of the present invention, when the oxygen carrier reduction reaction occurs to produce hydrogen, in addition to being able to pass methane gas, the type of fuel gas can also be changed to pass other types of hydrocarbons. When other types of fuel gas are passed, the ratio of water vapor to fuel gas can be changed according to actual needs to obtain the highest reactant conversion rate and the yield of generated gas. In the cyclic reaction process, the spherical oxygen carrier and absorbent in the moving bed can also be supplemented by the air reactor to ensure the efficient operation of the cyclic reaction.

[0054] The present application also provides a method for producing the above-mentioned chemical chaining step-by-step hydrogen and carbon monoxide production device, comprising:

[0055] The oxygen carrier and absorbent are introduced through the oxygen carrier and absorbent inlet of the fuel reactor, the hydrocarbon fuel is introduced through the fuel inlet of the fuel reactor, and the water vapor is introduced through the water vapor inlet of the fuel reactor, so that the mixed hydrocarbon fuel and water vapor react with the oxygen carrier to produce reduced oxygen carrier and carbon monoxide, carbon dioxide and hydrogen, the carbon dioxide in the fuel reactor is absorbed by the absorbent, and the carbon monoxide and water vapor are further reacted to produce hydrogen, and the produced hydrogen is discharged and collected;

[0056] Introducing a reduced oxygen carrier and an absorbent for absorbing carbon dioxide into the carbon dioxide oxidation reactor, presetting a set reaction temperature in the carbon dioxide oxidation reactor, desorbing the CO2 absorbent and oxidizing the oxygen carrier in situ, so that the absorbent after absorbing carbon dioxide desorbs in the carbon dioxide oxidation reactor to release carbon dioxide, and oxidizing the reduced oxygen carrier in situ to generate carbon monoxide, and the generated carbon monoxide is discharged and collected;

[0057] The partially oxidized oxygen carrier and the desorbed absorbent are introduced into the air reactor, and preheated air is introduced into the air reactor to completely oxidize the partially oxidized oxygen carrier. The completely oxidized oxygen carrier and the desorbed absorbent are lifted and introduced into the fuel reactor to participate in the next cycle.

[0058] The process method provided by the embodiment of the present invention can not only utilize the carbon dioxide produced in the reaction to reduce the emission of greenhouse gases, but also can produce two single high-quality industrial raw materials, hydrogen and carbon monoxide, in different reactors, respectively, avoiding the separation and purification of multiple product gases. The embodiment of the present invention fully combines the excellent properties of the iron-based oxygen carrier and the lithium silicate absorbent. By controlling the reaction materials and reaction conditions at different stages, a high concentration of hydrogen is produced during the reduction process of the oxygen carrier, and a single carbon monoxide is produced during the oxidation process of the oxygen carrier by carbon dioxide. In the process of producing a single hydrogen, the introduced methane and water vapor react with the iron-based oxygen carrier to produce carbon dioxide, hydrogen and carbon monoxide. The produced carbon monoxide will be further converted into hydrogen and carbon dioxide through the water gas shift reaction. The lithium silicate absorbent absorbs the carbon dioxide produced during the reduction reaction, and finally a single hydrogen is obtained by simple cooling separation. In the process of producing carbon monoxide, the reaction conditions are changed, and the carbon dioxide produced by desorption of the absorbent is used to oxidize the reduced oxygen carrier. At the same time, during the oxidation process of the oxygen carrier, the carbon dioxide will be reduced to carbon monoxide and discharged and collected from the top of the reactor. At the same time, the reduced ferrous oxide is oxidized to ferroferric oxide and then flows into the air reactor. The whole process realizes the separate production of hydrogen and carbon monoxide at different reaction stages through the circulation of the oxygen carrier and the absorbent in the moving bed, reducing the emission of greenhouse gases and fully improving the utilization rate of the reactants.

[0059] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A chemical chain step-by-step production device for hydrogen and carbon monoxide, characterized in that: include: fuel reactor, CO2 oxidation reactor and air reactor; The fuel reactor is respectively provided with an oxygen carrier and an absorbent inlet, a water vapor inlet, and a fuel inlet for introducing hydrocarbon fuel, which are used for the oxidation-reduction reaction of the mixed gas of hydrocarbon fuel and water vapor with the oxygen carrier, and the absorption reaction of carbon dioxide by the absorbent. The first outlet of the fuel reactor is used to discharge the reaction product hydrogen. The second outlet of the fuel reactor is connected to the inlet of the carbon dioxide oxidation reactor, and is used to introduce the reduced oxygen carrier after reduction and the absorbent after absorbing carbon dioxide into the carbon dioxide oxidation reactor. The carbon dioxide oxidation reactor is preset with a set reaction temperature, so that the absorbent after absorbing carbon dioxide desorbs in the carbon dioxide oxidation reactor to release carbon dioxide, and the generated carbon dioxide oxidizes the reduced oxygen carrier. The first outlet of the carbon dioxide oxidation reactor is used to discharge the reaction product carbon monoxide gas, and the second outlet of the carbon dioxide oxidation reactor is connected to the first inlet of the air reactor, so as to introduce the partially oxidized oxygen carrier and the desorbed absorbent into the air reactor; Air is introduced into the second inlet of the air reactor to completely oxidize the partially oxidized oxygen carrier and to lift the completely oxidized oxygen carrier and the desorbed absorbent. The outlet of the air reactor is connected to the oxygen carrier and absorbent inlet of the fuel reactor to introduce the oxygen carrier and absorbent into the fuel reactor to participate in the next cycle.

2. The chemical chaining step-by-step production device for hydrogen and carbon monoxide according to claim 1 is characterized in that: It also includes a cooling and separation device, the inlet of which is connected to the first outlet of the fuel reactor and is used to cool and separate the product gas of the fuel reactor to obtain high-concentration hydrogen.

3. The chemical chaining step-by-step production device for hydrogen and carbon monoxide according to claim 1 is characterized in that: It also includes a cyclone separator, which is arranged at the outlet of the air reactor and is used for gas-solid separation to separate mixed solid particles of oxygen carrier and absorbent from high-temperature air.

4. The chemical chaining step-by-step hydrogen and carbon monoxide production device according to claim 1 is characterized in that: The fuel reactor and the carbon dioxide oxidation reactor are moving bed reactors, and the air reactor is a fast bed reactor.

5. The chemical chaining step-by-step production device for hydrogen and carbon monoxide according to claim 1, characterized in that: The fuel reactor and the carbon dioxide oxidation reactor are respectively provided with a plurality of baffles, a plurality of circular holes are evenly provided on the baffles, the plurality of baffles are respectively tilted at set angles, and the tilt directions of adjacent baffles are opposite.

6. The chemical chaining step-by-step hydrogen and carbon monoxide production device according to claim 1 is characterized in that: The oxygen carrier is a metal oxide oxygen carrier capable of reducing CO2 to CO, including any one of an iron-based oxygen carrier and a perovskite.

7. The chemical chaining step-by-step production device for hydrogen and carbon monoxide according to claim 1, characterized in that: The absorbent is any one of spherical lithium silicate, lithium zirconate and calcium oxide absorbent particles.

8. The chemical chaining step-by-step production device for hydrogen and carbon monoxide according to claim 1, characterized in that: It also includes a feeding device, which is connected to the air reactor and is used for adding oxygen carriers and absorbents.

9. The chemical chaining step-by-step production device for hydrogen and carbon monoxide according to claim 1, characterized in that: It also includes an air intake preheating device, and the fuel inlet and the water vapor inlet of the fuel reactor and the second inlet of the air reactor are respectively provided with the air intake preheating device.

10. A method for producing hydrogen and carbon monoxide by chemical chaining step-by-step production as claimed in any one of claims 1 to 9, characterized in that: include: The oxygen carrier and absorbent are introduced through the oxygen carrier and absorbent inlet of the fuel reactor, the hydrocarbon fuel is introduced through the fuel inlet of the fuel reactor, and the water vapor is introduced through the water vapor inlet of the fuel reactor, so that the hydrocarbon fuel and the water vapor are mixed and then undergo a reduction reaction with the oxygen carrier to produce a reduced oxygen carrier and carbon monoxide, carbon dioxide and hydrogen, the carbon dioxide in the fuel reactor is absorbed by the absorbent, and the carbon monoxide and water vapor are prompted to continue to react to produce hydrogen, and the produced hydrogen is discharged and collected; Introducing a reduced oxygen carrier and an absorbent for absorbing carbon dioxide into the carbon dioxide oxidation reactor, presetting a set reaction temperature in the carbon dioxide oxidation reactor, desorbing the CO2 absorbent and oxidizing the oxygen carrier in situ, so that the absorbent after absorbing carbon dioxide desorbs in the carbon dioxide oxidation reactor to release carbon dioxide, and oxidizing the reduced oxygen carrier in situ to generate carbon monoxide, and the generated carbon monoxide is discharged and collected; The partially oxidized oxygen carrier and the desorbed absorbent are introduced into the air reactor, and preheated air is introduced into the air reactor to completely oxidize the partially oxidized oxygen carrier. The completely oxidized oxygen carrier and the desorbed absorbent are lifted and introduced into the fuel reactor to participate in the next cycle.

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