CN110131964B

CN110131964B - Chemical-looping air separation method and system

Info

Publication number: CN110131964B
Application number: CN201910422338.9A
Authority: CN
Inventors: 李玖重; 孙志钦; 高晓红; 高跃成; 郜建松; 周天宇; 张婧帆
Original assignee: Sinopec Engineering Group Co Ltd
Current assignee: Sinopec Engineering Group Co Ltd
Priority date: 2019-05-21
Filing date: 2019-05-21
Publication date: 2020-09-29
Anticipated expiration: 2039-05-21
Also published as: CN110131964A

Abstract

The invention provides a chemical-looping air separation method and a system thereof, belonging to the technical field of air separation. The separation method comprises the step of carrying out medium-pressure oxygen absorption reaction on the micro-oxygen carrier and air to obtain oxygen-poor air and oxygen-rich oxygen carrier. And carrying out oxygen release reaction on the oxygen-enriched oxygen carrier to obtain an oxygen-deficient oxygen carrier and oxygen-enriched gas. And carrying out high-pressure oxygen absorption reaction on the oxygen-poor air and the oxygen-poor oxygen carrier to obtain a micro-oxygen carrier and nitrogen-rich gas. The separation system comprises a medium-pressure oxygen absorption reaction system, an oxygen release reaction system and a high-pressure oxygen absorption reaction system, and the high-pressure oxygen absorption reaction system is respectively connected with the medium-pressure oxygen absorption reaction system and the oxygen release reactor. The separation system can complete the circulation of the oxygen carrier under the condition of high pressure difference, and prepares high-purity oxygen and nitrogen by utilizing the irreversibility of oxygen absorption reaction under the conditions of high pressure and low temperature, thereby improving the efficiency and economic performance of the chemical-looping air separation technology. The energy consumption is low, the operation method is simple, and the operation is convenient.

Description

Chemical-looping air separation method and system

Technical Field

The invention relates to the technical field of air separation, in particular to a chemical-looping air separation method and a chemical-looping air separation system.

Background

Oxygen and nitrogen are important chemical raw materials, and have wide application in the fields of chemical industry, metallurgy, oil refining, medical treatment, military affairs and the like, and the preparation of oxygen and nitrogen is a very key technology. The common technologies for preparing oxygen and nitrogen by air separation at present include cryogenic rectification technology, membrane separation technology and pressure swing adsorption technology. The cryogenic rectification technology is the most mature air separation technology at present, the principle of the cryogenic rectification technology is that the air is liquefied by utilizing the different boiling points of nitrogen and oxygen in the air, and then the purpose of separating the nitrogen and the oxygen is achieved through cryogenic rectification. The pressure swing adsorption air separation technology has the defects of low productivity, high energy consumption and the like. The membrane separation technology has the defects of difficult preparation of membrane materials, high cost and the like.

The chemical-looping air separation technology is a new air separation technology, and compared with the conventional air separation technology, the chemical-looping air separation technology has the advantages of low energy consumption, quick start, low cost, convenience in operation and the like. However, the current chemical-looping air separation technology is focused on the research of oxygen preparation, but most of the prior art has the defects of high energy consumption, poor economy, low oxidation purity and the like. In addition, the purity of nitrogen in oxygen-poor air formed after the oxygen is prepared is low, and even through conventional subsequent treatment, the high purity of nitrogen cannot be obtained.

Disclosure of Invention

The first purpose of the invention comprises providing a chemical-looping air separation method, which can realize the circulation flow of oxygen under the condition of high pressure difference, has high reaction speed, low system energy consumption and simple and convenient operation, can simultaneously prepare high-purity oxygen and nitrogen, and effectively improves the efficiency and economic performance of the chemical-looping air separation technology.

The second purpose of the invention comprises providing a chemical-looping air separation system, which adopts high-pressure, medium-pressure and low-pressure reactors to complete the circulation of oxygen carriers under the condition of high pressure difference, utilizes the irreversibility of oxygen absorption reaction under the condition of high pressure and low temperature, simultaneously prepares high-purity oxygen and nitrogen, and improves the efficiency and economic performance of the chemical-looping air separation technology.

The third purpose of the invention comprises providing a method for air separation by using the chemical-looping air separation system, which has the advantages of low energy consumption and convenient operation.

The technical problem to be solved by the invention is realized by adopting the following technical scheme:

the invention provides a chemical-looping air separation method, which comprises the following steps:

and carrying out medium-pressure oxygen absorption reaction on the micro-oxygen carrier and air to obtain oxygen-poor air and oxygen-rich oxygen carrier.

And carrying out oxygen release reaction on the oxygen-enriched oxygen carrier to obtain an oxygen-deficient oxygen carrier and oxygen-enriched gas.

And carrying out high-pressure oxygen absorption reaction on the oxygen-poor air and the oxygen-poor oxygen carrier to obtain a micro-oxygen carrier and nitrogen-rich gas.

Wherein the pressure of the medium-pressure oxygen absorption reaction is 1-3MPa, and the temperature is 650-1000 ℃; the pressure of the oxygen release reaction is 0.1-0.5MPa, and the temperature is 600-990 ℃; the pressure of the high-pressure oxygen absorption reaction is 3-5MPa, and the temperature is 500-900 ℃.

In some preferred embodiments, the pressure of the high pressure oxygen uptake reaction is 2-5MPa higher than the pressure of the medium pressure oxygen uptake reaction, and the temperature of the high pressure oxygen uptake reaction is 100-500 ℃ lower than the temperature of the medium pressure oxygen uptake reaction.

The invention provides a chemical-looping air separation system,

and the medium-pressure oxygen absorption reaction system is used for performing medium-pressure oxygen absorption reaction on the micro-oxygen carrier and air to obtain oxygen-poor air and oxygen-rich oxygen carrier.

And the oxygen release reaction system is used for carrying out oxygen release reaction on the oxygen-enriched oxygen carrier to obtain an oxygen-poor oxygen carrier and oxygen-enriched gas.

And the high-pressure oxygen absorption reaction system is used for carrying out high-pressure oxygen absorption reaction on the oxygen-poor air and the oxygen-poor oxygen carrier to obtain the micro-oxygen carrier and the nitrogen-rich air.

Wherein, high pressure oxygen uptake reaction system includes high pressure oxygen uptake reactor, and middling pressure oxygen uptake reaction system includes middling pressure oxygen uptake reactor, and oxygen release reaction system includes the oxygen release reactor, and high pressure oxygen uptake reactor is connected with middling pressure oxygen uptake reactor and oxygen release reactor respectively.

The reaction pressure of the high-pressure oxygen absorption reactor is not lower than that of the medium-pressure oxygen absorption reactor, and the reaction pressure of the medium-pressure oxygen absorption reactor is higher than that of the oxygen release reactor; preferably, the reaction pressure of the high-pressure oxygen absorption reactor is 3-5MPa, and the reaction temperature is 500-900 ℃; the reaction pressure of the medium-pressure oxygen absorption reactor is 1-3MPa, and the reaction temperature is 650-1000 ℃; the reaction pressure of the aerobic reactor is 0.1-0.5MPa, and the reaction temperature is 600-990 ℃.

In some embodiments, the pressure of the high-pressure oxygen absorption reactor is 2-5MPa higher than that of the medium-pressure oxygen absorption reactor, and the temperature of the high-pressure oxygen absorption reactor is 100-500 ℃ lower than that of the medium-pressure oxygen absorption reactor.

Further, when the high-pressure oxygen absorption reactor, the medium-pressure oxygen absorption reactor and the oxygen discharge reactor are all fluidized bed reactors, the high-pressure oxygen absorption reaction system further comprises a gas turbine, a first preheating device and a first pressure boosting device; the medium-pressure oxygen absorption reaction system also comprises second preheating equipment, a second collector, a variable-pressure feeder and second boosting equipment; the oxygen evolution reaction system also comprises a third collector, a third preheating device and a cooling device.

The inlet end of the high-pressure oxygen absorption reactor is connected with the outlet end of the pressure swing feeder and the outlet end of the second pressure boosting device respectively, the outlet end of the high-pressure oxygen absorption reactor is connected with the inlet end of the gas turbine, and the inlet end of the first preheating device is connected with the outlet end of the gas turbine and the outlet end of the first pressure boosting device respectively.

The inlet end of the second preheating device is respectively connected with the outlet end of the first preheating device and the outlet end of the medium-pressure oxygen absorption reactor, and the outlet end of the second preheating device is respectively connected with the inlet ends of the medium-pressure oxygen absorption reactor and the second pressure boosting device.

The inlet end of the pressure swing feeder is connected with the outlet end of the medium pressure oxygen absorption reactor and the outlet end of the third collector respectively, the inlet end of the second collector is connected with the outlet end of the pressure swing feeder and the outlet end of the third preheating device respectively, the outlet end of the third preheating device is also connected with the cooling device, the inlet end of the third preheating device is connected with the outlet end of the oxygen release reactor, and the inlet end of the oxygen release reactor is connected with the outlet end of the second collector and the outlet end of the third preheating device respectively.

Further, when the high-pressure oxygen absorption reactor, the medium-pressure oxygen absorption reactor and the oxygen release reactor are all moving bed reactors, the high-pressure oxygen absorption reaction system further comprises a first variable-pressure feeder, a first ascending buffer tank, a gas turbine and first preheating equipment; the medium-pressure oxygen absorption reaction system also comprises a second variable-pressure feeder, a second preheating device and a second ascending buffer tank; the oxygen release reaction system also comprises a third pressure swing feeder, a third ascending buffer tank and a third preheating device.

The outlet end of the high-pressure oxygen absorption reactor is respectively connected with a gas turbine and a first ascending buffer tank, the outlet end of the gas turbine is connected with the inlet end of first preheating equipment, and the inlet end of the high-pressure oxygen absorption reactor is respectively connected with the outlet end of second preheating equipment and the outlet end of a first variable-pressure feeder.

The inlet end of the medium-pressure oxygen absorption reactor is connected with the outlet end of the second preheating device and the outlet end of the second variable-pressure feeder respectively, the inlet end of the second variable-pressure feeder is connected with the outlet end of the first ascending buffer tank, the outlet end of the medium-pressure oxygen absorption reactor is connected with the inlet end of the second preheating device and the second ascending buffer tank respectively, and the inlet end of the second preheating device is further connected with the outlet end of the first preheating device.

The inlet end of the deoxidation reactor is respectively connected with the outlet end of the third variable-pressure feeder and the outlet end of the third preheating device, the inlet end of the third variable-pressure feeder is connected with the outlet end of the second ascending buffer tank, the outlet end of the deoxidation reactor is respectively connected with the inlet end of the third ascending buffer tank and the inlet end of the third preheating device, and the outlet end of the third ascending buffer tank is connected with the inlet end of the first variable-pressure feeder.

In addition, the invention also provides a method for separating air by using the chemical-looping air separation system, which comprises the following steps:

in a medium-pressure oxygen absorption reactor, a micro-oxygen carrier and air which enters after pressurization, heat exchange and temperature rise are subjected to oxidation reaction to generate oxygen-poor air and an oxygen-rich oxygen carrier.

Inputting the generated oxygen-enriched oxygen carrier into an oxygen release reactor, and diluting the oxygen-enriched oxygen carrier with water vapor in the oxygen release reactor to carry out oxygen release reaction to generate an oxygen-poor oxygen carrier and oxygen-enriched gas; and carrying out gas-liquid separation on the oxygen-enriched gas, and collecting the separated oxygen.

Inputting the oxygen-poor air into a high-pressure oxygen absorption reactor, reacting the oxygen-poor air with an oxygen-poor carrier in the high-pressure oxygen absorption reactor to generate a micro-oxygen carrier, simultaneously, converting the oxygen-poor air into nitrogen after losing oxygen, and collecting the nitrogen.

The chemical-looping air separation method and the chemical-looping air separation system have the beneficial effects that:

firstly, the system has low energy consumption, low cost and convenient operation. The chemical-looping air separation system realizes the recycling of the oxygen carrier under high pressure difference, the system operation cost is only the electricity consumption and partial heat energy of the booster equipment, and the system operation cost is lower and the energy consumption is low; in the oxygen generation part, the micro-oxygen carrier generates oxygen absorption reaction under the condition of high pressure and higher than the oxygen release temperature, the oxygen carrier enters a low-pressure oxygen release reactor when the temperature of the oxygen carrier is higher than the oxygen release temperature, the oxygen release reaction can be performed spontaneously without providing heat from the outside, and the oxygen generation cost can be reduced by 6 percent compared with the normal-pressure chemical-looping oxygen generation technology; meanwhile, the process can prepare high-purity nitrogen while preparing oxygen, the efficiency and the economy of air separation are further improved, the operation cost is reduced by about 1/3 compared with the conventional air separation technology, and the system is simple to operate and convenient to operate.

Secondly, nitrogen with the purity of more than 99 percent and oxygen with the purity of more than 99 percent can be simultaneously prepared. The process of the invention adopts high-pressure, medium-pressure and low-pressure reactors to complete the circulation of the oxygen carrier under the condition of high pressure difference, and utilizes the irreversibility of oxygen absorption reaction under the condition of high pressure and low temperature to separate so as to simultaneously obtain nitrogen with the purity of more than 99 percent and oxygen with the purity of more than 99 percent. Compared with the existing chemical chain oxygen production process, the process can separate high-purity nitrogen while preparing high-purity oxygen, and further improves the separation efficiency and the economical efficiency of the chemical chain separation technology.

Thirdly, the separation efficiency is high, and the continuous and stable operation of the air separation process under the condition of high pressure difference can be realized. The process of the invention adopts the moving bed, the fluidized bed and the pressure-changing feeder to realize the circular flow reaction of the oxygen carrier under the condition of high pressure difference, the oxygen carrier and the reaction gas are in contact reaction with each other in the reactor in a flowing way, the mass and heat transfer effect and the temperature uniformity of the reactor are greatly improved compared with those of a fixed bed reactor, and the reaction rate and the reaction depth are effectively enhanced; compared with the chemical chain pressurization oxygen production process of the fixed bed reactor, the process of frequently switching the valves is avoided, and the influence of frequent switching of the valves on the stability and reliability of the system is avoided. Therefore, the process can realize efficient, continuous and stable operation of the air separation process.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic diagram of a first configuration of a chemical looping air separation system provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of a second configuration of a chemical looping air separation system provided in an embodiment of the present application;

FIG. 3 is a schematic structural view of a portion of the high pressure oxygen uptake reaction system of FIG. 2;

FIG. 4 is a schematic diagram of the structure of a portion of the medium pressure oxygen-uptake reaction system of FIG. 2;

FIG. 5 is a schematic structural view of a part of the oxygen release reaction system in FIG. 2.

Icon: 100-chemical looping air separation system; 10-high pressure oxygen uptake reaction system; 11-a high pressure oxygen absorption reactor; 111-a first inlet of the high pressure oxygen absorption reactor; 112-a second inlet of the high pressure oxygen absorption reactor; 113-a first outlet of the high pressure oxygen absorption reactor; 114-a second outlet of the high-pressure oxygen absorption reactor; 12-a gas turbine; 13-a first preheating device; 131-a first inlet of a first preheating device; 132 — first preheat equipment second inlet; 133-first outlet of first preheating device; 134-first preheating device second outlet; 14-a first boost device; 15-a first gas-solid separation device; 151-first outlet of first gas-solid separation device; 152-a second outlet of the first gas-solid separation device; 16-a transition storage tank; 20-a medium-pressure oxygen absorption reaction system; 21-a medium pressure oxygen absorption reactor; 211-a first inlet of the medium pressure oxygen absorption reactor; 212-second inlet of medium pressure oxygen absorption reactor; 213-a first outlet of the medium pressure oxygen absorption reactor; 214-a second outlet of the medium pressure oxygen absorption reactor; 22-a second preheating device; 221-a second preheating device first inlet; 222-a second inlet of a second preheating device; 223-a first outlet of the second preheating device; 224-a second outlet of the second preheating device; 23-a second collector; 24-a variable pressure feeder; 241-a first inlet of a pressure swing feeder; 242-pressure swing feeder second inlet; 243-third inlet of pressure swing feeder; 244-first variable pressure feeder; 245-a second pressure swing feeder; 246-third pressure swing feeder; 25-a second boost device; 30-an oxygen evolution reaction system; 31-an oxygen release reactor; 311-oxygen carrier inlet; 312-a steam inlet; 313-a first inlet of the exothermic reactor; 314-the secondary inlet of the aerobic reactor; 315-a first outlet of the aerobic reactor; 316-a second outlet of the aerobic reactor; 32-a third collector; 33-a third preheating device; 331-a third preheating device first inlet; 332-third preheating device second inlet; 333-first outlet of third preheating device; 334-second outlet of third preheating device; 34-a cooling device; 341-cooling device first outlet; 342-a cooling device second outlet; 41-a first collector; 42-a first communication pipe; 43-a filter; 44-second gas-solid separation equipment; 45-a first riser; 46-a second riser; 51-a first valve; 52-a second valve; 53-a third valve; 54-a fourth valve; 55-a fifth valve; 56-sixth valve; 61-first rising cache tank; 62-a second ascending buffer tank; 63-a third ascending buffer tank; 71-a first buffer tank; 72-a second buffer tank; 73-third buffer tank.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships conventionally put in use of products of the present invention, and are only for convenience of description and simplification of description, but do not indicate or imply that the devices or elements referred to must have specific orientations, be constructed in specific orientations, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

Furthermore, the term "vertical" or the like does not require that the components be perfectly vertical, but rather may be slightly inclined. For example, "vertical" merely means that the direction is more vertical than "horizontal", and does not mean that the structure must be perfectly vertical, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," and "connected" are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1

The present embodiments provide a chemical looping air separation method, which may include:

and carrying out medium-pressure oxygen absorption reaction on the micro-oxygen carrier and air to obtain oxygen-poor air and oxygen-rich oxygen carrier. And carrying out oxygen release reaction on the oxygen-enriched oxygen carrier to obtain an oxygen-deficient oxygen carrier and oxygen-enriched gas. And carrying out high-pressure oxygen absorption reaction on the oxygen-poor air and the oxygen-poor oxygen carrier to obtain a micro-oxygen carrier and nitrogen-rich gas.

In the process of the high-pressure oxygen absorption reaction, the oxygen absorption reaction of the oxygen carrier is irreversible, namely the oxygen carrier does not generate the oxygen release reaction under the condition, and oxygen in the mixed gas can be completely absorbed.

In the middle-pressure oxygen absorption reaction process, oxygen release reaction and oxygen absorption reaction of the oxygen carrier are simultaneously carried out, and the oxygen volume content in the gas can be 0-20.8% in the balance process, preferably 5-15%.

It is worth to be noted that the oxygen-poor or micro-oxygen carrier can not undergo irreversible oxygen absorption reaction under high-pressure and low-temperature conditions, that is, the oxygen release reaction does not occur, and the oxygen in the mixed gas can be completely reacted. The irreversible reaction can ensure that the oxygen carrier can completely react with oxygen in the mixed gas, and the purity of nitrogen is higher than 99 percent.

In some embodiments, the pressure of the medium-pressure oxygen absorption reaction may be 1-3MPa, and the temperature may be 650-; the pressure of the oxygen release reaction can be 0.1-0.5MPa, and the temperature can be 600-; the pressure of the high-pressure oxygen absorption reaction can be 3-5MPa, and the temperature can be 500-900 ℃. Specifically, the pressure difference and the reaction temperature are different according to different types of oxygen carriers.

In some embodiments, the pressure of the high pressure oxygen uptake reaction is 2-5MPa higher than the pressure of the medium pressure oxygen uptake reaction, and the temperature of the high pressure oxygen uptake reaction is 100-500 ℃ lower than the temperature of the medium pressure oxygen uptake reaction.

Optionally, the oxygen carrier comprises a metallic oxygen carrier or a non-metallic oxygen carrier, the metallic oxygen carrier comprises one or more of a copper-based oxygen carrier, an iron-based oxygen carrier and a manganese-based oxygen carrier, and the non-metallic oxygen carrier comprises GaSO₄One or more of an oxygen carrier and a perovskite oxygen carrier.

By reference, the oxygen carrier may be selected from CoO, Co₂O₃、Co₃O₄；Fe₂O₃、FeO、Fe₃O₄、MnO、MnO₂、Mn₂O₃Or perovskite, and the oxygen carriers have micro-oxygen, oxygen-rich and oxygen-poor states.

In some embodiments, the oxygen-rich oxygen carrier is CuO and the oxygen-deficient oxygen carrier is Cu₂O, micro-oxygen carrier is CuO and Cu₂And the mass fraction of CuO in the mixture can be 30-50%.

Further, the chemical looping air separation method further comprises: oxygen carrier generated by high-pressure oxygen absorption reaction is used for medium-pressure oxygen absorption reaction.

In the conventional air separation technology, the low-temperature rectification technology utilizes the different boiling points of nitrogen and oxygen in the air to liquefy the air and then carry out low-temperature rectification to achieve the aim of separating the nitrogen and the oxygen, and has the advantages of large technical investment, high cost, high energy consumption and complex operation. The pressure swing adsorption air separation technology also has the defects of low productivity, high energy consumption and the like. The membrane separation technology has the defects of difficult membrane material preparation, high cost and the like, so compared with the conventional air separation technology, the chemical-looping air separation method provided by the application can reduce the cost.

In summary, the chemical-looping air separation method provided by the embodiment is simple, convenient to operate, capable of preparing high-purity oxygen and nitrogen simultaneously, and capable of improving efficiency and economic performance of a chemical-looping air separation technology.

Example 2

Referring to fig. 1 and fig. 2 together, the chemical looping air separation system 100 of the present embodiment includes a high pressure oxygen absorption reaction system 10, a medium pressure oxygen absorption reaction system 20, and an oxygen release reaction system 30.

The medium-pressure oxygen absorption reaction system 20 is used for performing medium-pressure oxygen absorption reaction on the micro-oxygen carrier and air to obtain oxygen-poor air and oxygen-rich oxygen carrier. The oxygen release reaction system 30 is used for performing an oxygen release reaction on the oxygen-enriched oxygen carrier to obtain an oxygen-depleted oxygen carrier and oxygen-enriched gas. The high-pressure oxygen absorption reaction system 10 is used for carrying out high-pressure oxygen absorption reaction on the oxygen-poor air and the oxygen-poor oxygen carrier to obtain a micro-oxygen carrier and nitrogen-rich air.

The high-pressure oxygen absorption reaction system 10 comprises a high-pressure oxygen absorption reactor 11, the medium-pressure oxygen absorption reaction system 20 comprises a medium-pressure oxygen absorption reactor 21, the oxygen release reaction system 30 comprises an oxygen release reactor 31, and the high-pressure oxygen absorption reactor 11 is respectively connected with the medium-pressure oxygen absorption reactor 21 and the oxygen release reactor 31.

Wherein, the reaction pressure of the high pressure oxygen absorption reactor 11 is not lower than the reaction pressure of the medium pressure oxygen absorption reactor 21, and the reaction pressure of the medium pressure oxygen absorption reactor 21 is higher than the reaction pressure of the oxygen release reactor 31.

Alternatively, the reaction pressure of the high pressure oxygen absorption reactor 11 may be, for example, 3 to 5MPa, and the reaction temperature may be, for example, 500-900 ℃. The reaction pressure of the medium pressure oxygen absorption reactor 21 may be, for example, 1 to 3MPa, and the reaction temperature may be, for example, 650-. The reaction pressure of the deoxidation reactor 31 may be, for example, 0.1 to 0.5MPa, and the reaction temperature may be, for example, 600-. Specifically, the pressure difference and the reaction temperature are different according to different types of oxygen carriers.

Preferably, the pressure of the high-pressure oxygen absorption reactor 11 is 2-5MPa higher than that of the medium-pressure oxygen absorption reactor 21, and the temperature of the high-pressure oxygen absorption reactor 11 is 100-500 ℃ lower than that of the medium-pressure oxygen absorption reactor 21.

The oxygen carrier is used for circularly operating to prepare oxygen and nitrogen by the matching of the high-pressure oxygen absorption reaction system 10, the medium-pressure oxygen absorption reaction system 20 and the oxygen discharge reaction system 30.

The specific choice of oxygen carrier can be found in example 1.

The air separation process of the chemical looping air separation system 100 described above may include: in the medium-pressure oxygen absorption reactor 21, the micro-oxygen carrier and the air which enters after pressurization, heat exchange and temperature rise are subjected to oxidation reaction to generate oxygen-poor air and oxygen-rich oxygen carrier.

Inputting the generated oxygen-enriched oxygen carrier into an oxygen release reactor 31, and diluting the oxygen-enriched oxygen carrier with water vapor in the oxygen release reactor 31 to carry out oxygen release reaction to generate an oxygen-deficient oxygen carrier and oxygen-enriched gas; and carrying out gas-liquid separation on the oxygen-enriched gas, and collecting the separated oxygen.

Inputting the oxygen-poor air into the high-pressure oxygen absorption reactor 11, reacting the oxygen-poor air with the oxygen-rich oxygen carrier in the high-pressure oxygen absorption reactor 11 to generate a micro-oxygen carrier, and simultaneously, the oxygen-poor air loses oxygen and is converted into nitrogen, and collecting the nitrogen.

Wherein the volume flow of the air is lower than the theoretical flow of the oxygen-poor oxygen carrier completely converted into the oxygen-rich oxygen carrier, and the non-equivalence ratio coefficient is 0.6-0.95.

Example 3

With reference to example 2 and with continued reference to fig. 1, when the high-pressure oxygen absorption reactor 11, the medium-pressure oxygen absorption reactor 21 and the oxygen release reactor 31 in the chemical looping air separation system 100 are all fluidized bed reactors, the high-pressure oxygen absorption reaction system 10 further includes a gas turbine 12, a first preheating device 13 and a first pressure increasing device 14, the medium-pressure oxygen absorption reaction system 20 further includes a second preheating device 22, a second collector 23, a pressure swing feeder 24 and a second pressure increasing device 25, and the oxygen release reaction system 30 further includes a third collector 32, a third preheating device 33 and a cooling device 34.

The inlet end of the high-pressure oxygen absorption reactor 11 is respectively connected with the outlet end of the pressure swing feeder 24 and the outlet end of the second pressure boosting device 25. The outlet end of the high-pressure oxygen absorption reactor 11 is connected with the inlet end of a gas turbine 12. The inlet end of the first preheating device 13 is connected to the outlet end of the gas turbine 12 and to the outlet end of the first pressure-boosting device 14, respectively.

The inlet end of the second preheating device 22 is connected with the outlet end of the first preheating device 13 and the outlet end of the medium pressure oxygen absorption reactor 21, respectively, and the outlet end of the second preheating device 22 is connected with the inlet ends of the medium pressure oxygen absorption reactor 21 and the second pressure boosting device 25, respectively.

The inlet end of the pressure swing feeder 24 is respectively connected with the outlet end of the medium pressure oxygen absorption reactor 21 and the outlet end of the third collector 32, the inlet end of the second collector 23 is respectively connected with the outlet end of the pressure swing feeder 24 and the outlet end of the third preheating device 33, the outlet end of the third preheating device 33 is also connected with the cooling device 34, the inlet end of the third preheating device 33 is connected with the outlet end of the oxygen release reactor 31, and the inlet end of the oxygen release reactor 31 is respectively connected with the outlet end of the second collector 23 and the outlet end of the third preheating device 33.

The high-pressure oxygen absorption reaction system 10 further comprises a first gas-solid separation device 15 and a transition storage tank 16, wherein the outlet end of the high-pressure oxygen absorption reactor 11 is connected with the inlet end of the first gas-solid separation device 15, the outlet end of the first gas-solid separation device 15 is respectively connected with the inlet end of the gas turbine 12 and the inlet end of the transition storage tank 16, the outlet end of the transition storage tank 16 is further connected with the medium-pressure oxygen absorption reactor 21, and the inlet end of the transition storage tank 16 is further connected with the outlet end of the second preheating device 22.

Further, a first collector 41 is connected between the pressure swing feeder 24 and the medium pressure aerobic reactor 21, and a first communicating pipe 42 is connected between the first collector 41 and the medium pressure aerobic reactor 21. A filter 43 is connected between the medium pressure oxygen absorption reactor 21 and the second preheating device 22.

Furthermore, a second gas-solid separation device 44 is further disposed in the aerobic reactor 31, and the aerobic reactor 31 is further provided with a steam inlet 312 and an oxygen carrier inlet 311, respectively, the oxygen carrier inlet 311 is connected with the outlet end of the second collector 23, and the steam inlet 312 is connected with the outlet end of the third preheating device 33.

For reference, in this embodiment, the high pressure aerobic reactor 11 has a first inlet 111 of the high pressure aerobic reactor and a second inlet 112 of the high pressure aerobic reactor. The first preheating device 13 has a first preheating device first inlet 131, a first preheating device second inlet 132, a first preheating device first outlet 133 and a first preheating device second outlet 134. The second preheating device 22 has a second preheating device first inlet 221, a second preheating device second inlet 222, a second preheating device first outlet 223, and a second preheating device second outlet 224. The medium-pressure oxygen absorption reactor 21 is provided with a first inlet 211 of the medium-pressure oxygen absorption reactor and a second inlet 212 of the medium-pressure oxygen absorption reactor. The pressure swing feeder 24 has a first pressure swing feeder inlet 241, a second pressure swing feeder inlet 242, and a third pressure swing feeder inlet 243. The third preheating device 33 has a third preheating device first inlet 331, a third preheating device second inlet 332, a third preheating device first outlet 333 and a third preheating device second outlet 334. The cooling device 34 has a cooling device first outlet 341 and a cooling device second outlet 342.

The first inlet 111 of the high-pressure oxygen absorption reactor is connected with the outlet end of the second boosting device 25, the second inlet 112 of the high-pressure oxygen absorption reactor is connected with the outlet end of the pressure-changing feeder 24, and the outlet end of the high-pressure oxygen absorption reactor 11 is connected with the inlet end of the first gas-solid separation device 15. The upper outlet of the first gas-solid separation device 15 is connected to the inlet end of the gas turbine 12 and the lower outlet of the first gas-solid separation device 15 is connected to the second inlet of the transition storage tank 16.

The first inlet 131 of the first preheating device is connected with the outlet end of the first boosting device 14, the second inlet of the first preheating device 13 is connected with the outlet end of the gas turbine 12, the first outlet 133 of the first preheating device is connected with the first inlet 221 of the second preheating device, and the second outlet 134 of the first preheating device is used for outputting nitrogen.

The second inlet 222 of the second preheating device is connected with the outlet end of the filter 43, the first outlet 223 of the second preheating device is divided into two parallel branches, one branch is connected with the first inlet of the medium pressure oxygen absorption reactor 21, and the other branch is connected with the first inlet of the transition storage tank 16. A second outlet of the second preheating device 22 is connected to an inlet end of a second boosting device 25. The outlet end of the transition storage tank 16 is connected with the second inlet of the medium pressure oxygen absorption reactor 21.

The first inlet 241 of the pressure swing feeder is connected with the outlet end of the first collector 41, the second inlet 242 of the pressure swing feeder is connected with the outlet end of the third collector 32, and the third inlet 243 of the pressure swing feeder is used for introducing oxygen-deficient air and water vapor. The outlet end of the pressure swing feeder 24 is divided into two branches, one branch is connected with the second inlet 112 of the high pressure oxygen absorption reactor, and the other branch is connected with the inlet end of the second collector 23.

A first outlet of the aerobic reactor 31 is connected with an inlet end of the third collector 32, and a second outlet of the aerobic reactor 31 is connected with a first inlet of the third preheating device 33.

The second inlet 332 of the third preheating device is connected with the first outlet 341 of the cooling device, the first outlet 333 of the third preheating device is connected with the inlet end of the cooling device 34, and the second outlet 334 of the third preheating device is connected with the oxygen carrier inlet 311 of the aerobic reactor 31.

Further, a first riser tube 45 is arranged between the second outlet 334 of the third preheating device and the oxygen carrier inlet 311, and a second riser tube 46 is arranged between the first outlet 315 of the aerobic reactor and the inlet end of the third collector 32.

Furthermore, a first valve 51 is arranged between the outlet end of the first collector 41 and the first inlet 241 of the pressure swing feeder, a second valve 52 is arranged between the outlet end of the pressure swing feeder 24 and the inlet end of the second collector 23, a fourth valve 54 is arranged between the outlet end of the pressure swing feeder 24 and the second inlet 112 of the high pressure oxygen absorption reactor, and a third valve 53 is arranged between the outlet end of the third collector 32 and the second inlet 242 of the pressure swing feeder.

By way of reference, the operation of the chemical looping air separation system 100 described above may be such (it is worth noting that the following specific data in parentheses referring to the data ranges may be integrated into one embodiment, as follows):

air (the non-equivalent ratio coefficient is 0.6-0.95, e.g., 0.9) at normal temperature and normal pressure enters the first pressure increasing device 14, the pressure rises to 1-3MPa (e.g., 1.5MPa), the air enters the first preheating device 13 through the first inlet 131 of the first preheating device to exchange heat with high-temperature nitrogen, the air rises to 200-.

The micro oxygen carrier (CuO/Cu) with the temperature of 500-₂O) enters the transition storage tank 16 from a gas-solid separation device dipleg (a second outlet 152 of the first gas-solid separation device) through a second inlet of the transition storage tank 16, and the micro oxygen carrier in the transition storage tank 16 enters the medium-pressure oxygen absorption reactor 21 through a communicating pipe connected with the second inlet 212 of the medium-pressure oxygen absorption reactor under the lifting of air with temperature of 600-. The oxygen carrier is under the pressure of 1-3MPa (such as 1.5MPa), the ascending side and the air are subjected to oxidation reaction under the fluidization action of the air, and heat is released, so that oxygen-poor air with the temperature of 650-1000 ℃ (such as 950 ℃) and oxygen-rich oxygen carrier with the temperature of 650-1000 ℃ (such as 950 ℃) are generated. The equation for the oxygen uptake reaction is shown below,

the oxygen-deficient air with the temperature of 650 plus 1000 ℃ (such as 950 ℃) enters the second preheating device 22 from the upper part of the medium-pressure endothermic reactor 21 through the filter 43 after oxygen carrier particles are filtered out, the temperature is reduced to 300 plus 600 ℃ (such as 500 ℃) and then enters the second pressure boosting device 25 through the second outlet 224 of the second preheating device, the pressure is boosted to 3-5MPa (such as 4MPa) and enters the high-pressure endothermic reactor 11 from the first inlet 111 of the high-pressure endothermic reactor at the bottom of the high-pressure endothermic reactor 11.

The oxygen-enriched carrier with the temperature of 650 plus 1000 ℃ (such as 950 ℃) runs to the upper part of the medium-pressure oxygen absorption reactor 21, enters the first collector 41 from the first connecting pipe 42, when the pressure in the pressure change feeder 24 is reduced to be 10-50kPa (such as 20kPa) lower than that of the first collector 41, the first valve 51 is opened, the oxygen-enriched carrier enters the pressure change feeder 24 through the first inlet 241 of the pressure change feeder by means of the self gravity, and the first valve 51 is closed when the oxygen-enriched height in the pressure change feeder 24 reaches the set position. The pressure swing feeder 24 is depressurized, steam purge air is introduced at 400 ℃ and 650 ℃ (such as 600 ℃), the steam purge is continuously introduced for pressurization after the purge is completed, the second valve 52 is opened when the pressure of the pressure swing feeder 24 is 10-50kPa (such as 20kPa) higher than that of the second collector 23, and the oxygen-enriched oxygen carrier enters the second collector 23 at 640 ℃ and 990 ℃ (such as 940 ℃) by means of self gravity. After the variable pressure feeder 24 finishes discharging, the second valve 52 is closed and the pressure is relieved, and when the pressure is reduced to the normal pressure, the third valve 53 is opened to wait for feeding.

The oxygen-enriched oxygen carrier in the second collector 23 at 640-990 ℃ (such as 940 ℃) enters from the oxygen carrier inlet 311 at the middle part of the exothermic reactor 31 through the first riser 45 under the lifting of the steam at 400-650 ℃ (such as 600 ℃). Under the fluidization of water vapor with the temperature of 400-650 ℃ (such as 600 ℃) entering from a vapor inlet at the lower part of the exothermic reactor 31, oxygen release reaction occurs under the pressure of 0.1-0.5MPa (such as 0.2MPa) while ascending, and 500-900 ℃ (such as 800 ℃) oxygen-poor oxygen carrier (Cu)₂O) and 500 ℃ and 900 ℃ (e.g., 800 ℃). The equation for the oxygen evolution reaction is shown below,

oxygen-enriched gas with the temperature of 500 plus 900 ℃ (such as 800 ℃) is led out from a second outlet 316 of the aerobic reactor at the upper part of the aerobic reactor 31 through the second gas-solid separation equipment 44, enters the third preheating equipment 33 through a first inlet 331 of the third preheating equipment, reduces the heat exchange temperature with water to 80-150 ℃ (such as 100 ℃), then enters the cooling equipment 34 through a first outlet 333 of the third preheating equipment for gas-liquid separation to obtain condensed water and O with the purity of more than 99% (such as 99.9%)₂，O₂And (6) carrying out collection treatment.

The condensed water is output through the first outlet 341 of the cooling device, mixed with the make-up water, and then enters the third preheating device 33 through the second inlet 332 of the third preheating device, and becomes water vapor of 400-. Most of the water vapor enters from a vapor inlet at the middle lower part of the aerobic reactor 31 to be used as diluent gas to be mixed with oxygen released by the oxygen-enriched oxygen carrier to generate oxygen-enriched gas, and a small part of the water vapor is used as fluidized wind to lift the oxygen carrier.

The oxygen-deficient oxygen carrier with the temperature of 500-900 ℃ (such as 800 ℃) returns to the bottom of the anaerobic reactor 31 under the separation of the second gas-solid separation equipment 44, and enters the third collector 32 through the second riser pipe 46 connected with the first outlet 315 of the anaerobic reactor under the lifting of the high-temperature steam with the temperature of 400-650 ℃ (such as 600 ℃).

After the third valve 53 is opened after the pressure in the pressure swing feeder 24 is reduced to normal pressure, the oxygen-depleted carrier at 500 ℃ and 900 ℃ (e.g., 800 ℃) in the third collector 32 enters the pressure swing feeder 24 through the second inlet 242 of the pressure swing feeder by gravity. The third valve 53 is closed when the oxygen carrier level of the pressure swing feeder 24 reaches the set position. High-pressure oxygen-poor air with the temperature of 300-600 ℃ (such as 500 ℃) is introduced into the pressure-changing feeder 24 for pressurization, when the pressure of the pressure-changing feeder 24 is 10-50kPa (such as 20kPa) higher than that of the high-pressure aerobic reactor 11, the fourth valve 54, 490-890 ℃ (such as 780 ℃) oxygen-poor carrier enters the lower part of the high-pressure aerobic reactor 11 from the second inlet 112 of the high-pressure aerobic reactor by means of self gravity. After the pressure of the pressure swing feeder 24 is discharged, the fourth valve 54 is closed and the pressure is released, and when the pressure of the pressure swing feeder 24 is lower than the pressure of the first accumulator 41 by 10-50kPa (such as 20kPa), the first valve 51 is opened to wait for feeding.

The oxygen-depleted air entering the high pressure oxygen absorption reactor 11 at 300-600 ℃ (e.g., 500 ℃) reacts with the oxygen-depleted carrier entering from the pressure swing feeder 24 at a pressure of 3-5MPa (e.g., 4MPa) and releases heat. Generating the micro-oxygen carrier with the temperature of 500-900 ℃, and converting oxygen-deficient air into high-concentration nitrogen with the temperature of 500-900 ℃ (such as 850 ℃) after losing oxygen. The equation for the oxygen uptake reaction is shown below,

the micro oxygen carrier with 500-900 ℃ (such as 850 ℃) in the high pressure oxygen absorption reactor 11 enters the first cyclone separation under the fluidization of oxygen-deficient air for gas-solid separation. The micro oxygen carrier with 500 ℃ and 900 ℃ (such as 850 ℃) enters the transition storage tank 16 from the gas-solid separation equipment dipleg for circulation.

The high-concentration nitrogen with the temperature of 500 plus 900 ℃ (such as 850 ℃) is led out from the upper part (the first outlet 151 of the first gas-solid separation device) of the first gas-solid separation device 15 and enters a gas turbine 12, the high-temperature and high-pressure work of the nitrogen is utilized to generate electricity, the pressure is reduced to 0.1-0.5MPa (such as 0.2MPa), the temperature is reduced to 300 plus 700 ℃ (such as 600 ℃) and enters the first preheating device 13 through the second inlet 132 of the first preheating device to heat air, the temperature is reduced to below 50 ℃ to carry out collection treatment, and the purity of the nitrogen is higher than 99%.

Example 4

With reference to example 2, please continue to refer to fig. 2 to 5, when the high pressure aerobic reactor 11, the medium pressure aerobic reactor 21 and the aerobic reactor 31 in the chemical looping air separation system 100 are all moving bed reactors; the high-pressure oxygen absorption reaction system 10 further comprises a first pressure swing feeder 244, a first ascending buffer tank 61, a gas turbine 12 and a first preheating device 13; the medium-pressure oxygen absorption reaction system 20 further comprises a second pressure-swing feeder 245, a second preheating device 22 and a second ascending buffer tank 62; the oxygen evolution reaction system 30 further comprises a third pressure swing feeder 246, a third lift buffer tank 63 and a third preheating device 33.

The outlet end of the high-pressure oxygen absorption reactor 11 is respectively connected with the gas turbine 12 and the first ascending buffer tank 61, the outlet end of the gas turbine 12 is connected with the inlet end of the first preheating device 13, and the inlet end of the high-pressure oxygen absorption reactor 11 is respectively connected with the outlet end of the second preheating device 22 and the outlet end of the first pressure swing feeder 244.

The inlet end of the medium pressure oxygen absorption reactor 21 is connected with the outlet end of the second preheating device 22 and the outlet end of the second pressure swing feeder 245, the inlet end of the second pressure swing feeder 245 is connected with the outlet end of the first ascending buffer tank 61, the outlet end of the medium pressure oxygen absorption reactor 21 is connected with the inlet end of the second preheating device 22 and the second ascending buffer tank 62, and the inlet end of the second preheating device 22 is further connected with the outlet end of the first preheating device 13.

The inlet end of the deoxygenation reactor 31 is connected to the outlet end of the third pressure swing feeder 246 and the outlet end of the third preheating device 33, the inlet end of the third pressure swing feeder 246 is connected to the outlet end of the second ascending buffer tank 62, the outlet end of the deoxygenation reactor 31 is connected to the inlet end of the third ascending buffer tank 63 and the inlet end of the third preheating device 33, and the outlet end of the third ascending buffer tank 63 is connected to the inlet end of the first pressure swing feeder 244.

Further, a first collector 41 is disposed between the first variable pressure feeder 244 and the third ascending buffer tank 63, a second collector 23 is disposed between the second variable pressure feeder 245 and the first ascending buffer tank 61, and a third collector 32 is disposed between the third variable pressure feeder 246 and the second collector 23.

Further, a first buffer tank 71 is arranged between the high-pressure aerobic reactor 11 and the first ascending buffer tank 61, a second buffer tank 72 is arranged between the medium-pressure aerobic reactor 21 and the second ascending buffer tank 62, and a third buffer tank 73 is arranged between the deoxygenation reactor 31 and the third ascending buffer tank 63.

Further, the inlet end of the first preheating device 13 is also connected with a first pressure boosting device 14, a second pressure boosting device 25 is further arranged between the second preheating device 22 and the high-pressure aerobic reactor 11, and the third preheating device 33 is also connected with a cooling device 34.

For reference, the first preheating device 13 has a first preheating device first inlet 131, a first preheating device second inlet 132, a first preheating device first outlet 133 and a first preheating device second outlet 134. The high-pressure oxygen absorption reactor 11 has a first inlet 111 of the high-pressure oxygen absorption reactor, a second inlet 112 of the high-pressure oxygen absorption reactor, a first outlet 113 of the high-pressure oxygen absorption reactor, and a second outlet 114 of the high-pressure oxygen absorption reactor. The second preheating device 22 has a second preheating device first inlet 221, a second preheating device second inlet 222, a second preheating device first outlet 223, and a second preheating device second outlet 224. The medium-pressure oxygen absorption reactor 21 is provided with a first inlet 211 of the medium-pressure oxygen absorption reactor, a second inlet 212 of the medium-pressure oxygen absorption reactor, a first outlet 213 of the medium-pressure oxygen absorption reactor and a second outlet 214 of the medium-pressure oxygen absorption reactor. The third preheating device 33 has a third preheating device first inlet 331, a third preheating device second inlet 332, a third preheating device first outlet 333 and a third preheating device second outlet 334. The aerobic reactor 31 has an aerobic reactor first inlet 313, an aerobic reactor second inlet 314, an aerobic reactor first outlet 315, and an aerobic reactor second outlet 316. The cooling device 34 has a cooling device first outlet 341 and a cooling device second outlet 342.

The first inlet 131 of the first preheating device is connected with the outlet end of the first pressure boosting device 14, the second inlet 132 of the first preheating device is connected with the first outlet 113 of the high-pressure endothermic reactor, the first outlet 133 of the first preheating device is used for outputting nitrogen, and the second outlet 134 of the first preheating device is connected with the first inlet 221 of the second preheating device.

The first inlet 111 of the high-pressure oxygen absorption reactor is connected with the outlet end of the first pressure-changing feeder 244, the second inlet 112 of the high-pressure oxygen absorption reactor is connected with the outlet end of the second pressure boosting device 25, and the second outlet 114 of the high-pressure oxygen absorption reactor is connected with the inlet end of the first buffer tank 71.

The second inlet 222 of the second preheating device is connected with the first outlet 213 of the medium-pressure oxygen absorption reactor, the first outlet 223 of the second preheating device is connected with the second inlet 212 of the medium-pressure oxygen absorption reactor, and the second outlet 224 of the second preheating device is connected with the inlet end of the second pressure boosting device 25.

The first inlet 211 of the medium-pressure oxygen absorption reactor is connected with the outlet end of the second pressure swing feeder 245, and the second outlet 214 of the medium-pressure oxygen absorption reactor is connected with the inlet end of the second buffer tank 72.

The first inlet 331 of the third preheating device is connected with the first outlet 315 of the aerobic reactor, the second inlet 332 of the third preheating device is connected with the first outlet 341 of the cooling device, the first outlet 333 of the third preheating device is connected with the inlet end of the cooling device 34, and the second outlet 334 of the third preheating device is connected with the second inlet 314 of the aerobic reactor.

The first inlet 313 of the aerobic reactor is connected with the outlet end of the third pressure swing feeder 246, and the second outlet 316 of the aerobic reactor is connected with the inlet end of the third buffer tank 73.

Furthermore, a first valve 51 is arranged between the first collector 41 and the first pressure swing feeder 244, a second valve 52 is arranged between the first pressure swing feeder 244 and the high pressure adsorption reactor 11, a third valve 53 is arranged between the second collector 23 and the second pressure swing feeder 245, a fourth valve 54 is arranged between the second pressure swing feeder 245 and the medium pressure adsorption reactor 21, a fifth valve 55 is arranged between the third collector 32 and the third pressure swing feeder 246, and a sixth valve 56 is arranged between the third pressure swing feeder 246 and the aerobic reactor 31.

By reference, the operation of the chemical looping air separation system 100 may be:

in the high pressure oxygen absorption reaction system 10, normal temperature and pressure air (with a non-equivalence ratio coefficient of 0.6-0.95, e.g., 0.9) enters the first pressure increasing device 14, the pressure is increased to 1-3MPa (e.g., 1.5MPa) and enters the first preheating device 13 through the first inlet 131 of the first preheating device to exchange heat with high temperature nitrogen, the temperature is increased to 200-.

500-₂O) enters the second collector 23 from the oxygen-deficient air with the temperature of 300-650 ℃ (such as 500 ℃) through the first lifting pipe 45, oxygen carrier enters the second pressure swing feeder 245 by means of gravity, and the third valve 53 is closed after the oxygen carrier level in the second pressure swing feeder 245 reaches the set height.

The second pressure swing feeder 245 is vented to release pressure, when the pressure of the pressure swing feeder 24 is 10-50kPa (such as 20kPa) higher than that of the medium pressure oxygen absorption reactor 21, the fourth valve 54 is opened, and the temperature is 500-₂O) enters the medium-pressure oxygen absorption reactor 21 from the first inlet 211 of the medium-pressure oxygen absorption reactor at the upper part of the medium-pressure oxygen absorption reactor 21 by means of self gravity. After the second variable pressure feeder 245 discharges, the fourth valve 54 is closed, and the first valve 51 is opened to charge the material.

The high temperature air entering the medium pressure oxygen absorption reactor 21 and the high temperature oxygen carrier are oxidized under the pressure of 1-3MPa (such as 1.5MPa) and release heat, thus generating oxygen-poor air with the temperature of 650-1000 ℃ (such as 950 ℃) and oxygen-rich oxygen carrier with the temperature of 650-1000 ℃ (such as 950 ℃). The equation for the oxygen uptake reaction is shown below,

high-pressure oxygen-poor air with the temperature of 650 plus 1000 ℃ (such as 950 ℃) is led out from a first outlet 213 of the medium-pressure oxygen absorption reactor at the lower part of the medium-pressure oxygen absorption reactor 21 and enters the second preheating device 22 through a second inlet 222 of the second preheating device, the temperature is reduced to 300 plus 600 ℃ and enters the second pressure increasing device 25, the pressure is increased to 3-5MPa (such as 4MPa) and enters the high-pressure reactor from a second outlet 224 of the second preheating device through a second inlet 112 of the high-pressure oxygen absorption reactor at the upper end of the high-pressure reactor.

Oxygen-rich oxygen carriers (CuO) of 650-. The oxygen-rich carrier in the second lift buffer tank 62 is transported by the high-pressure air at 600 ℃ and 950 ℃ (such as 900 ℃) to the third collector 32 through the second riser 46.

The oxygen carrier in the third collector 32 enters the third pressure swing feeder 246 by gravity, and the fifth valve 55 is closed after the oxygen carrier level in the third pressure swing feeder 246 reaches the set height.

The third pressure swing feeder 246 is depressurized, after the pressure is reduced to normal pressure, 300-650 ℃ high temperature steam purge air is introduced into the third pressure swing feeder 246 for pressurization, when the pressure of the pressure swing feeder 24 is 10-50kPa higher than that of the deoxidation reactor 31, the sixth valve 56 is opened, and the oxygen-enriched oxygen carrier (CuO) with the temperature reduced to 600-990 ℃ (such as 930 ℃) enters the deoxidation reactor 31 from the first inlet 313 of the deoxidation reactor at the upper part of the deoxidation reactor 31 by means of the self-gravity.

After the third pressure swing feeder 246 is discharged, the sixth valve 56 is closed and the fifth valve 55 is opened for charging.

The high-temperature oxygen-rich oxygen carrier entering the oxygen release reactor 31 carries out oxygen release reaction under the pressure of 0.1-0.5MPa (such as 0.2MPa), and the oxygen-rich oxygen carrier is changed into an oxygen-poor oxygen carrier with the temperature of 500-900 ℃ (such as 800 ℃); the water vapor with temperature of 300-650 ℃ (such as 600 ℃) enters the aerobic reactor 31 through the second inlet 314 of the aerobic reactor to be mixed with the oxygen released by the oxygen-rich oxygen carrier, so as to generate oxygen-rich gas with temperature of 500-900 ℃ (such as 800 ℃). The equation for the oxygen evolution reaction is shown below,

oxygen-enriched gas with the temperature of 500 plus 900 ℃ (such as 800 ℃) enters the third preheating device 33 through the first outlet 315 of the exothermic reactor and the first inlet 331 of the third preheating device, the temperature is reduced to 80-150 ℃ (such as 100 ℃) and enters the cooling device 34 through the first outlet 333 of the third preheating device for gas-liquid separation, and condensed water and O with the purity of more than 99% (such as 99.9%) are obtained₂，O₂And (6) carrying out collection treatment. The condensed water output from the first outlet 341 of the cooling device is mixed with the make-up water and enters the third preheating device 33 through the second inlet 332 of the third preheating device to be changed into water vapor of 300-.

500 ℃ and 900 ℃ (e.g., 800 ℃) oxygen-deficient oxygen carriers (Cu₂O) enters the third buffer tank 73 through the second outlet 316 of the aerobic reactor by self gravity according to the lifting speed of the oxygen carrier in the third ascending buffer tank 63, and then enters the third ascending buffer tank 63 to be lifted to the first collector 41 by the water vapor with the temperature of 300-650 ℃ (such as 600 ℃) through the third riser.

The oxygen carrier in the first collector 41 enters the first pressure-changing feeder 244 by gravity, and the first valve 51 is closed after the oxygen carrier level in the first pressure-changing feeder 244 reaches the set height.

The first pressure swing feeder 244 is depressurized, after the pressure is reduced to normal pressure, oxygen-poor air with temperature of 300-650 ℃ (such as 500 ℃) is introduced into the first pressure swing feeder 244 to purge water vapor and pressurize the first pressure swing feeder, when the pressure of the pressure swing feeder 24 is 10-50kPa (such as 20kPa) higher than that of the high pressure oxygen absorption reactor 11, the second valve 52 is opened, and the oxygen-poor carrier with temperature reduced to 490-890 ℃ (such as 780 ℃) enters the high pressure oxygen absorption reactor 11 from the first inlet 111 of the high pressure oxygen absorption reactor at the upper end of the high pressure oxygen absorption reactor 11 by means of self gravity.

After the first pressure swing feeder 244 discharges, the second valve 52 is closed and the pressure relief operation is performed, and the first valve 51 is opened to the pressure of the normal pressure to charge.

The oxygen-poor carrier entering the high-pressure oxygen absorption reactor 11 reacts with oxygen-poor air under the pressure of 3-5MPa (such as 4MPa) and releases heat, so as to generate the micro-oxygen carrier with the temperature of 500-900 ℃ (such as 850 ℃), and the oxygen-poor air loses oxygen and is converted into high-concentration nitrogen with the temperature of 500-900 ℃ (such as 850 ℃). The equation for the oxygen uptake reaction is shown below,

the nitrogen with the temperature of 500 plus 900 ℃ (such as 850 ℃) is led out from a first outlet 113 of the high-pressure oxygen absorption reactor at the lower part of the high-pressure oxygen absorption reactor 11 and enters a gas turbine 12, the high-temperature and high-pressure work of the nitrogen is utilized to generate electricity, the pressure is reduced to 0.1-0.5MPa (such as 0.2MPa), the temperature is reduced to 300 plus 700 ℃ (such as 600 ℃) and enters a first preheating device 13 through a second inlet 132 of the first preheating device to heat air, the temperature is reduced to below 50 ℃ to carry out collection treatment, and the purity of the nitrogen is higher than 99%.

The micro oxygen carrier with the temperature of 500 ℃ and 900 ℃ (such as 850 ℃) sequentially enters the first buffer tank 71 through the second outlet 114 of the high-pressure oxygen absorption reactor according to the lifting speed of the oxygen carrier in the first ascending buffer tank 61 by means of self gravity, and then enters the first ascending buffer tank 61 to finish one cycle of the oxygen carrier.

To sum up, the chemical-looping air separation system 100 provided by the application completes the circulation of the oxygen carrier under the condition of high pressure difference by adopting high-pressure, medium-pressure and low-pressure reactors respectively, and prepares high-purity oxygen and nitrogen by utilizing the irreversibility of oxygen absorption reaction under the condition of high pressure and low temperature, thereby improving the efficiency and economic performance of the chemical-looping air separation technology. The operation method is simple and convenient to operate.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A chemical looping air separation process, comprising:

carrying out medium-pressure oxygen absorption reaction on the micro-oxygen carrier and air to obtain oxygen-poor air and an oxygen-rich oxygen carrier;

carrying out oxygen release reaction on the oxygen-enriched oxygen carrier to obtain an oxygen-deficient oxygen carrier and oxygen-enriched gas;

carrying out high-pressure oxygen absorption reaction on the oxygen-poor air and the oxygen-poor oxygen carrier to obtain a micro-oxygen carrier and a nitrogen-rich gas;

2. The chemical looping air separation method as claimed in claim 1, wherein the pressure of the high pressure oxygen absorption reaction is 2-5MPa higher than the pressure of the medium pressure oxygen absorption reaction, and the temperature of the high pressure oxygen absorption reaction is 100-500 ℃ lower than the temperature of the medium pressure oxygen absorption reaction.

3. The chemical looping air separation method according to claim 1, characterized in that it further comprises: the micro oxygen carrier generated by the high-pressure oxygen absorption reaction is used for the medium-pressure oxygen absorption reaction.

4. A chemical looping air separation system, comprising:

the medium-pressure oxygen absorption reaction system is used for carrying out medium-pressure oxygen absorption reaction on the micro-oxygen carrier and air to obtain oxygen-poor air and oxygen-rich oxygen carrier;

the oxygen release reaction system is used for carrying out oxygen release reaction on the oxygen-enriched oxygen carrier to obtain an oxygen-deficient oxygen carrier and oxygen-enriched gas;

and the high-pressure oxygen absorption reaction system is used for carrying out high-pressure oxygen absorption reaction on the oxygen-poor air and the oxygen-poor oxygen carrier to obtain a micro-oxygen carrier and nitrogen-rich gas.

5. The chemical looping air separation system of claim 4, wherein the high pressure oxygen uptake reaction system comprises a high pressure oxygen uptake reactor, the medium pressure oxygen uptake reaction system comprises a medium pressure oxygen uptake reactor, the oxygen release reaction system comprises a oxygen release reactor, and the high pressure oxygen uptake reactor is connected with the medium pressure oxygen uptake reactor and the oxygen release reactor respectively;

the reaction pressure of the high-pressure oxygen absorption reactor is not lower than that of the medium-pressure oxygen absorption reactor, and the reaction pressure of the medium-pressure oxygen absorption reactor is higher than that of the oxygen release reactor.

6. The chemical looping air separation system as claimed in claim 5, wherein the reaction pressure of the high pressure oxygen absorption reactor is 3-5MPa, and the reaction temperature is 500-900 ℃; the reaction pressure of the medium-pressure oxygen absorption reactor is 1-3MPa, and the reaction temperature is 650-1000 ℃; the reaction pressure of the aerobic reactor is 0.1-0.5MPa, and the reaction temperature is 600-.

7. The chemical looping air separation system of claim 6, wherein the pressure of the high-pressure aerobic reactor is 2-5MPa higher than that of the medium-pressure aerobic reactor, and the temperature of the high-pressure aerobic reactor is 100-500 ℃ lower than that of the medium-pressure aerobic reactor.

8. The chemical looping air separation system of claim 4, wherein the high pressure oxygen absorption reactor, the medium pressure oxygen absorption reactor and the oxygen release reactor are fluidized bed reactors;

the high-pressure oxygen absorption reaction system also comprises a gas turbine, a first preheating device and a first boosting device; the medium-pressure oxygen absorption reaction system also comprises second preheating equipment, a second collector, a pressure-changing feeder and second boosting equipment; the oxygen release reaction system also comprises a third collector, third preheating equipment and cooling equipment;

the inlet end of the high-pressure oxygen absorption reactor is respectively connected with the outlet end of the pressure swing feeder and the outlet end of the second pressure boosting equipment, the outlet end of the high-pressure oxygen absorption reactor is connected with the inlet end of the gas turbine, and the inlet end of the first preheating equipment is respectively connected with the outlet end of the gas turbine and the outlet end of the first pressure boosting equipment;

the inlet end of the second preheating device is respectively connected with the outlet end of the first preheating device and the outlet end of the medium-pressure oxygen absorption reactor, and the outlet end of the second preheating device is respectively connected with the inlet ends of the medium-pressure oxygen absorption reactor and the second pressure boosting device;

the entry end of vary voltage feeder respectively with the exit end of middling pressure oxygen absorption reactor and the exit end of third collector is connected, the entry end of second collector respectively with the exit end of vary voltage feeder and the exit end of third preheating device is connected, the exit end of third preheating device still with cooling arrangement connects, the entry end of third preheating device with the exit end of aerobic reactor is connected, the entry end of aerobic reactor respectively with the exit end of second collector and the exit end of third preheating device is connected.

9. The chemical looping air separation system according to claim 8, wherein the high-pressure oxygen absorption reaction system further comprises a first gas-solid separation device and a transition storage tank, the outlet end of the high-pressure oxygen absorption reactor is connected with the inlet end of the first gas-solid separation device, the outlet end of the first gas-solid separation device is respectively connected with the inlet end of the gas turbine and the inlet end of the transition storage tank, the outlet end of the transition storage tank is further connected with the medium-pressure oxygen absorption reactor, and the inlet end of the transition storage tank is further connected with the outlet end of the second preheating device.

10. The chemical looping air separation system of claim 8, wherein a first collector is further connected between the pressure swing feeder and the medium pressure oxygen absorption reactor;

and/or a filter is connected between the medium-pressure oxygen absorption reactor and the second preheating equipment.

11. The chemical looping air separation system according to claim 8, wherein a second gas-solid separation device is arranged in the aerobic reactor, the aerobic reactor is further provided with a steam inlet and an oxygen carrier inlet respectively, the oxygen carrier inlet is connected with an outlet end of the second collector, and the steam inlet is connected with an outlet end of the third preheating device.

12. The chemical looping air separation system of claim 4, wherein the high pressure oxygen absorption reactor, the medium pressure oxygen absorption reactor and the aerobic reactor are moving bed reactors;

the high-pressure oxygen absorption reaction system also comprises a first pressure swing feeder, a first ascending buffer tank, a gas turbine and first preheating equipment; the medium-pressure oxygen absorption reaction system also comprises a second pressure-changing feeder, a second preheating device and a second ascending buffer tank; the oxygen release reaction system also comprises a third pressure swing feeder, a third ascending buffer tank and a third preheating device;

the outlet end of the high-pressure oxygen absorption reactor is respectively connected with the gas turbine and the first ascending buffer tank, the outlet end of the gas turbine is connected with the inlet end of the first preheating device, and the inlet end of the high-pressure oxygen absorption reactor is respectively connected with the outlet end of the second preheating device and the outlet end of the first variable-pressure feeder;

the inlet end of the medium-pressure oxygen absorption reactor is respectively connected with the outlet end of the second preheating device and the outlet end of the second variable-pressure feeder, the inlet end of the second variable-pressure feeder is connected with the outlet end of the first ascending buffer tank, the outlet end of the medium-pressure oxygen absorption reactor is respectively connected with the inlet end of the second preheating device and the second ascending buffer tank, and the inlet end of the second preheating device is also connected with the outlet end of the first preheating device;

the inlet end of the aerobic reactor is respectively connected with the outlet end of the third variable pressure feeder and the outlet end of the third preheating device, the inlet end of the third variable pressure feeder is connected with the outlet end of the second ascending buffer tank, the outlet end of the aerobic reactor is respectively connected with the inlet end of the third ascending buffer tank and the inlet end of the third preheating device, and the outlet end of the third ascending buffer tank is connected with the inlet end of the first variable pressure feeder.

13. The chemical looping air separation system of claim 12, wherein a first collector is disposed between the first variable pressure feeder and the third ascending buffer tank, a second collector is disposed between the second variable pressure feeder and the first ascending buffer tank, and a third collector is disposed between the third variable pressure feeder and the second collector.

14. The chemical looping air separation system of claim 12, wherein a first buffer tank is arranged between the high-pressure aerobic reactor and the first ascending buffer tank, a second buffer tank is arranged between the medium-pressure aerobic reactor and the second ascending buffer tank, and a third buffer tank is arranged between the aerobic reactor and the third ascending buffer tank.

15. A method of air separation using a chemical looping air separation system of any of claims 4-14, comprising the steps of:

carrying out oxidation reaction on a micro-oxygen carrier and air entering after pressurization, heat exchange and temperature rise in the medium-pressure oxygen absorption reactor to generate oxygen-poor air and an oxygen-rich oxygen carrier;

inputting the generated oxygen-enriched oxygen carrier into the aerobic reactor and carrying out oxygen release reaction on the oxygen-enriched oxygen carrier in a water vapor environment in the aerobic reactor to generate an oxygen-deficient oxygen carrier and oxygen-enriched gas; carrying out gas-liquid separation on the oxygen-enriched gas, and collecting separated oxygen;

inputting the oxygen-poor air into the high-pressure oxygen absorption reactor, reacting the oxygen-poor air with an oxygen-poor carrier in the high-pressure oxygen absorption reactor to generate a micro oxygen carrier, converting the oxygen-poor air into nitrogen after losing oxygen, and collecting the nitrogen.

16. The method of claim 15, wherein the volumetric flow rate of the air is below the theoretical flow rate for complete conversion of the oxygen-deficient oxygen carrier to the oxygen-rich oxygen carrier, and the non-equivalence ratio factor is 0.6-0.95.