An oxycombustion system and method

Abstract

The application discloses a magnetic method oxygen-enriched combustion system. In the system, the inlet of the combustion fan is communicated with the atmosphere through a filter, the outlet of the combustion fan is connected with a magnetic oxygen-enriched rotating disc through an adsorption channel inlet after passing through an air ionization assembly; the adsorption channel outlet of the magnetic oxygen-enriched rotating disc is communicated with the atmosphere, the desorption channel inlet is communicated with the cold end outlet of a heat exchanger, and the desorption channel outlet is connected with the combustion air inlet of a gas furnace; the cooling channel inlet of the magnetic oxygen-enriched rotating disc is connected with the gas phase outlet of a dehydration tank, and the cooling channel outlet is connected with the cold end inlet of the heat exchanger; the flue gas outlet of the combustion furnace is connected with the hot end inlet of the heat exchanger, the hot end outlet of the heat exchanger is divided into two paths after passing through a flue gas circulating fan, the first path is connected with the inlet of the dehydration tank, and the second path is discharged out of the system. The application realizes the supply of large amount of oxygen-enriched gas with high efficiency and low cost by the cooperation of the magnetic field and the magnetic medium according to the different paramagnetism and diamagnetism of oxygen molecules and nitrogen molecules.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of heating furnaces, and relates to a heating furnace energy-saving emission-reducing carbon-reducing technology and method, in particular to a system and method for realizing heating furnace energy-saving emission-reducing carbon-reducing by using a magnetic method oxygen-rich combustion mode. BACKGROUND

[0002] Under the background of carbon peak and carbon neutralization, domestic carbon emission reduction policies will become increasingly strict, and it is imperative for enterprises to gradually implement carbon capture measures on the basis of energy saving and emission reduction. At present, China's carbon emission reduction and capture technology is relatively mature, and carbon capture is mainly in the coal chemical industry, thermal power industry, steel manufacturing, natural gas processing, cement production, methanol, synthetic ammonia, hydrogen production and oil refining industries. Economic cost is an important factor restricting the development of China's CCUS, and in the CCUS capture, transportation, utilization and storage links, capture is the highest energy consumption and cost link. Relative to China's carbon dioxide emissions and emission reduction demand, the current CCUS emission reduction contribution is difficult to meet the urgent needs of China's low-carbon development.

[0003] Oxygen-rich combustion is an efficient energy-saving combustion technology. Oxygen-rich combustion refers to combustion with oxygen-rich gas with higher oxygen concentration than air. Compared with ordinary air combustion, it can effectively improve the flame temperature, improve the heat utilization rate, and reduce the exhaust loss. With the continuous development of oxygen-enriched preparation technology, oxygen-enriched combustion technology is applied more and more widely, and is gradually popularized to pulverized coal furnaces, circulating fluidized beds and industrial heating furnaces.

[0004] In the oxygen-enriched combustion process, the combustion technology is assisted by flue gas circulation, which can obtain high-concentration CO2-rich flue gas, realize carbon enrichment, and reduce the scale, investment and operation cost of the post-combustion carbon capture device, so as to realize CO2 recovery or resource utilization at a small cost. It is considered as one of the most possible large-scale popularization and commercialization of CCUS technology.

[0005] The cost of oxygen enrichment is the key to the overall investment and operating costs of oxygen-enriched combustion technology. Current oxygen enrichment technologies include cryogenic separation, pressure swing adsorption, membrane separation, and magnetic oxygen enrichment. Cryogenic separation is a process that uses the boiling point difference of each component after liquefaction to separate and purify. The process is mature, and the oxygen purity is high, but the energy consumption is large, mainly used for large-scale enterprise pure oxygen combustion CO2 capture. Pressure swing adsorption (PSA) is a method of separating gases by using the adsorption and desorption capacity of adsorbents to specific gases. It is generally used for medium and small-scale gas separation, usually requires two or more tanks to switch for adsorption and regeneration operation, and has problems such as high-frequency operation of switching valves, leakage, and failure. In addition, the regeneration energy consumption is high. Membrane separation technology is a method of separating nitrogen and oxygen in air under certain pressure by using membrane materials with special selective separation properties. It is suitable for medium and small-scale low-purity oxygen production. The key to membrane separation technology is to manufacture membrane materials with high flux, high selectivity, long service life, and easy cleaning. However, in actual application, there are problems such as dust and impurities causing membrane hole blockage of oxygen enrichment membrane, which shortens the service life of the membrane. Magnetic oxygen enrichment is a method that uses the different paramagnetic and diamagnetic properties of oxygen and nitrogen molecules to make the two gas molecules deflect in different directions when passing through a high magnetic field, thereby obtaining oxygen-enriched and nitrogen-enriched gases. It has the advantages of low energy consumption and low cost. However, existing magnetic oxygen enrichment devices generally have low efficiency, low oxygen enrichment concentration, small oxygen enrichment gas volume, and difficulty in separating oxygen from the enrichment magnetic field.

[0006] Nitrogen oxide emission control under oxygen-enriched combustion conditions is another key factor that restricts this technology. As the oxygen volume fraction increases, the flame temperature rises, generating more thermal nitrogen oxides, resulting in an increase in nitrogen oxide concentration in the flue gas, which to some extent restricts the promotion and application of oxygen-enriched combustion. Therefore, it is crucial to adopt appropriate low-nitrogen emission reduction technology during oxygen-enriched combustion.

[0007] CN104271217A discloses an oxygen separator and a method for producing oxygen, which realizes the oxygen separation process by multi-cycle intermittent operation of the oxygen separation adsorbent. The technology needs to switch the operation of multiple sets of oxygen separators to realize continuous oxygen supply, and can only provide small amount of oxygen supply. Patent CN101450792A discloses a method for separating oxygen and nitrogen from air, which is carried out on a platform composed of a mixed conductor oxygen-permeable ceramic membrane separator and a pressure swing adsorption separator using complex metal oxides as an oxygen adsorbent. Most of the oxygen in the air is adsorbed by the mixed conductor oxygen-permeable ceramic membrane, and the remaining air is oxygen-poor air. The complex metal oxides as the adsorbent of the pressure swing adsorption separator adsorb the oxygen in the oxygen-poor air, and then the oxygen is obtained by vacuum desorption. The separation of nitrogen and oxygen in the air is realized by two steps of permeation and pressure swing adsorption. The system is complex, has high requirements for the performance of the membrane material, and needs to be frequently switched for regeneration. In the regeneration process, the adsorbent needs to be desorbed and penetrate the membrane material, and the system has high energy consumption. Patent CN101857200A discloses a new combined magnetic oxygen enrichment device using magnetic separation technology. The oxygen enrichment device uses three-stage series oxygen enrichment to gradually increase the oxygen purity, but there is a problem that oxygen is difficult to separate from the magnetic field in actual operation.

[0008] Patent CN103343965A discloses a heating furnace system using oxygen-enriched combustion. The invention relates to a heating furnace system in which air and oxygen are pre-mixed and then supplied to a burner for combustion. The system uses oxygen-enriched combustion technology to realize effective utilization of low-calorific-value coal gas, and is more efficient, energy-saving and environmentally friendly. However, the original heating system burners need to be completely replaced with oxygen-enriched burners before the system can be applied, which has high investment cost.

[0009] Patent CN106545846A discloses a heating furnace low-NOx flue gas circulation oxygen-enriched combustion device and method. The device includes a main flue and a flue gas circulation branch flue. A part of the flue gas discharged from the heating furnace is circulated, and oxygen is mixed to form a mixed gas with an oxygen content of 21% to 30% and then sent to the burner as combustion-supporting gas, which greatly reduces the generation of NOx in the flue gas. However, the technology needs to be matched with a stable oxygen source, and the cost of oxygen enrichment is not considered. SUMMARY

[0010] The present application provides a magnetic oxygen-enriched combustion system and method, which can provide large amount of oxygen-enriched gas for oxygen-enriched combustion efficiently and at low cost, reduce and control nitrogen oxide emissions from the source, improve the thermal efficiency of the heating furnace, reduce the flue gas emission, recover the flue gas waste heat, enrich the CO2 concentration in the flue gas, and provide convenient conditions for subsequent CO2 capture and recovery.

[0011] To achieve the above-mentioned purpose, the first aspect of the present application provides an oxygen-enriched combustion system.

[0012] The oxygen-enriched combustion system comprises an air filter, a combustion air fan, an air ionization assembly, a heat exchanger, a combustion furnace, a flue gas circulating fan, a dehydration tank, a magnetic field assembly, a magnetic oxygen-enriched rotating disc and a supporting adsorption channel, a cooling channel and a desorption channel.

[0013] The combustion air fan inlet is communicated with the atmosphere through the filter, the combustion air fan outlet is connected with the magnetic oxygen-enriched rotating disc through the adsorption channel inlet and the air ionization assembly, and the adsorption channel outlet of the magnetic oxygen-enriched rotating disc is communicated with the atmosphere.

[0014] The desorption channel inlet of the magnetic oxygen-enriched rotating disc is communicated with the cold end outlet of the heat exchanger, and the desorption channel outlet of the magnetic oxygen-enriched rotating disc is connected with the combustion air inlet of the gas furnace.

[0015] The cooling channel inlet of the magnetic oxygen-enriched rotating disc is connected with the gas phase outlet of the dehydration tank, and the cooling channel outlet of the magnetic oxygen-enriched rotating disc is connected with the cold end inlet of the heat exchanger.

[0016] The flue gas outlet of the combustion furnace is connected with the hot end inlet of the heat exchanger, the hot end outlet of the heat exchanger is divided into two routes after passing through the flue gas circulating fan, the first route is connected with the inlet of the dehydration tank, and the second route is discharged out of the system.

[0017] Further, the dehydration tank is a cooling dehydration gas-liquid separation tank, and a refrigerant heat extraction facility is arranged in the dehydration tank.

[0018] Further, the heat exchanger is a gas-gas heat exchanger, and the form of the heat exchanger is not limited.

[0019] Further, the air ionization assembly is a plasma generator, preferably a non-equilibrium plasma generator.

[0020] Further, the magnetic oxygen-enriched rotating disc comprises an outer shell, an oxygen-enriched material rotating disc, a partition plate and a driving motor. The oxygen-enriched material rotating disc is a rotating disc filled with magnetic medium. The inner part of the outer shell is divided into an adsorption area, a desorption area and a cooling area by the partition plate, and is respectively communicated with the adsorption channel, the cooling channel and the desorption channel on the outer shell. The adsorption area accounts for 1 / 2 to 3 / 4 of the whole oxygen-enriched material rotating disc, the desorption area accounts for 1 / 4 to 1 / 8 of the whole oxygen-enriched material rotating disc, and the cooling area accounts for 1 / 4 to 1 / 8 of the whole oxygen-enriched material rotating disc. The oxygen-enriched material rotating disc is rotated by the driving motor, and the rotating speed can be adjusted according to requirements. The adjusting range of the rotating speed is generally 0.5 to 20 revolutions per hour, preferably 2 to 8 revolutions per hour.

[0021] Further, the adsorption area of the magnetic oxygen-enriched rotating disc is provided with a magnetic field assembly on both sides, the magnetic field assembly is composed of multiple magnets, and the magnets can be permanent magnets, electromagnets or superconducting magnets.

[0022] Further, the magnetic medium in the oxygen-enriched material runner is a substance capable of changing a uniform magnetic field into a non-uniform magnetic field with high gradient, which can be one or a combination of ball medium, toothed plate medium, mesh medium, rod medium, and steel wool medium, and the material is one or a combination of pure iron, low-carbon steel, ferrite magnetic stainless steel, and iron-cobalt-neodymium boride alloy.

[0023] Further, the combustion furnace can be a solid fuel, liquid fuel, and gas fuel combustion furnace, which has a fuel supply port, a combustion air supply port, and a flue gas exhaust pipeline.

[0024] The second aspect of the present application also provides an oxygen-enriched combustion method, wherein the above-mentioned magnetic method oxygen-enriched combustion system is applied.

[0025] An oxygen-enriched combustion method, comprising the following steps:

[0026] (1) The air is first ionized by an air ionization assembly after being pressurized by a combustion air fan, and is ionized into a non-equilibrium plasma state, and then enters the adsorption area of the magnetic oxygen-enriched runner through the adsorption channel. The oxygen in the air is adsorbed and enriched by the magnetic medium under the action of the magnetic field formed by the magnetic field assembly on both sides of the adsorption area, and the remaining air is oxygen-poor (nitrogen-rich) gas, which is discharged through the outlet of the adsorption channel.

[0027] (2) After the magnetic medium in the adsorption area of step (1) adsorbs and enriches the oxygen-enriched gas, the magnetic oxygen-enriched runner is rotated by a driving motor, and the magnetic medium is transferred to the desorption area. In this area, the magnetic medium loses magnetic force and releases paramagnetic oxygen gas due to the loss of external magnetic field. At the same time, the high-temperature flue gas from the heat exchanger enters the desorption area through the desorption channel for heating, further promoting the release of oxygen, and entering the combustion furnace as combustion air together with the flue gas.

[0028] (3) After the combustion air and fuel in step (2) are burned in the combustion furnace, the high-temperature flue gas is pressurized by a flue gas circulating fan after heat recovery, and is divided into two paths: the first path enters a dehydration tank for cooling and dehydration treatment, and the second path is discharged out of the system.

[0029] (4) The magnetic medium that releases oxygen after regeneration in step (2) continues to rotate to the cooling area, and at the same time, the low-temperature flue gas treated by the dehydration tank in step (3) enters the cooling channel of the magnetic oxygen-enriched runner to cool the regenerated high-temperature magnetic medium. The cooled magnetic medium continues to rotate to the adsorption area and continues to adsorb and accumulate oxygen under the action of the magnetic field, completing the entire adsorption-desorption magnetic method oxygen enrichment cycle.

[0030] Further, an air filter is arranged before the combustion air fan in step (1) to filter impurities in the air.

[0031] Further, the high-temperature flue gas in step (2) is CO2-rich flue gas, and the volume concentration of CO2 in the flue gas is higher than 15%.

[0032] Further, the mixed combustion-supporting air after regeneration in step (2) is oxygen-rich gas, and the volume concentration of O2 in the combustion-supporting air is greater than or equal to 21%.

[0033] Further, the temperature of the dehydration tank in step (3) is 10-60 DEG C, preferably 25-40 DEG C.

[0034] Further, the flue gas after pressurization treatment by the circulating fan in step (3) is divided into two routes, the first route accounts for 10-50% of the total amount of flue gas, and the second route accounts for 50-90% of the total amount of flue gas.

[0035] Further, the gas discharged from the second route in step (3) is CO2-rich flue gas, which can be further subjected to carbon capture or recovery treatment.

[0036] Further, the size of the adsorption zone, the desorption zone and the cooling zone and the rotational speed of the rotating wheel can be designed and adjusted according to the oxygen-enrichment target.

[0037] Further, the oxygen-enriching combustion method of the present application is suitable for oxygen-enriching combustion processes of various types of combustion furnaces for solid fuel, liquid fuel and gaseous fuel.

[0038] Compared with the prior art, the present application has the following beneficial effects:

[0039] 1、The magnetic oxygen-enriching rotating disc used in the present application is filled with a magnetic medium in the rotating wheel, and magnetic field assemblies are arranged on both sides of the adsorption zone in the rotating disc. The magnetic medium is used to replace the adsorption material in the prior art, and a high-gradient non-uniform magnetic field can be formed under the action of an external magnetic field. The magnetic oxygen-enriching rotating disc utilizes the different paramagnetic and diamagnetic properties of oxygen molecules and nitrogen molecules, and through the cooperation of the magnetic field and the magnetic medium, it efficiently and low-costly supplies a large amount of oxygen-enriched gas, solves the problems of low oxygen-enriching efficiency and difficulty in separating oxygen from the enriched magnetic field in the prior art, and makes the entire oxygen-enriching gas supply process continuous and stable.

[0040] 2、The oxygen-enriching combustion system of the present application uses high-temperature dehydrated flue gas to heat the magnetic medium, further strengthens oxygen desorption, and directly realizes the mixing of CO2-rich flue gas and O2-rich gas by using the magnetic medium, so as to mix the combustion-supporting air with the required oxygen concentration, and then combust with fuel, without the need to modify the original combustion system to realize the oxygen-enriching combustion of the furnace.

[0041] 3. A magnetic oxygen-enriched rotary table is used to separate nitrogen and oxygen in the air. Nitrogen separation reduces the amount of combustion air, thereby reducing the amount of flue gas generated, reducing exhaust heat loss, improving the thermal efficiency of the heating furnace, and reducing the generation of nitrogen oxides from raw materials. This reduces and controls nitrogen oxide emissions at the source. Combined with CO2-enriched flue gas recycling and regeneration, and mixing with oxygen-enriched gas, it is equivalent to using CO2 to replace N2 as a diluent gas, which greatly increases the concentration of CO2 in the flue gas, significantly reduces carbon capture costs, and provides convenient conditions for subsequent CO2 capture and recovery. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of an oxygen-enriched combustion system according to the present invention.

[0043] In the diagram, 1-air pipeline, 2-filter, 3-combustion fan, 4-heat exchanger, 5-combustion furnace, 6-flue gas circulation fan, 7-magnetic oxygen-enriching turntable, 8-adsorption channel, 9-cooling channel, 10-desorption channel, 11-first outlet of circulation fan, 12-second outlet of circulation fan, 13-fuel supply, 14-flue gas outlet of combustion furnace, 15-combustion air inlet, 16-dehydration tank, 17-drive motor, 18-baffle plate, 19-burner, 20-carbon capture and recovery device, 21-air ionization component, 22-magnetic field component, A-adsorption zone, B-desorption zone, C-cooling zone. Detailed Implementation

[0044] The following detailed description of an oxygen-enriched combustion system and method according to the present invention, in conjunction with the accompanying drawings and embodiments, does not limit the scope of the invention.

[0045] like Figure 1 As shown, the present invention provides an oxygen-enriched combustion system, the system comprising an air filter 2, a combustion fan 3, a heat exchanger 4, a combustion furnace 5, a flue gas circulation fan 6, a dehydration tank 16, a magnetic oxygen-enriched turntable 7 and supporting adsorption channels 8, cooling channels 9, desorption channels 10, an air ionization component 21, and a magnetic field component 22. The inlet of the combustion fan 3 is connected to the atmosphere through the filter 2; the outlet of the combustion fan 3 is connected to the magnetic oxygen-enriched turntable 7 through the inlet of the adsorption channel 8 after passing through the air ionization component 21; the outlet of the adsorption channel 8 of the magnetic oxygen-enriched turntable 7 is connected to the atmosphere; the inlet of the desorption channel 10 of the magnetic oxygen-enriched turntable 7 is connected to the cold end outlet of the heat exchanger 4, and the outlet of the desorption channel 10 of the magnetic oxygen-enriched turntable 7 is connected to the combustion air inlet 15 of the gas furnace; the inlet of the cooling channel 9 of the magnetic oxygen-enriched turntable 7 is connected to the outlet of the dehydration tank 16, and the outlet of the cooling channel 9 of the magnetic oxygen-enriched turntable 7 is connected to the cold end inlet of the heat exchanger 4; the flue gas outlet 14 of the combustion furnace is connected to the hot end inlet of the heat exchanger 4, and the hot end outlet of the heat exchanger 4 is divided into two paths after passing through the flue gas circulation fan 6, the first path 11 is connected to the inlet of the dehydration tank, and the second path 12 is discharged out of the system.

[0046] The magnetic oxygen-enriching rotating disc 7 is composed of an oxygen-enriching material rotating disc 7, a partition plate 18 and a driving motor 17. The oxygen-enriching material rotating disc 7 is a rotating wheel filled with a magnetic medium; the internal space of the magnetic oxygen-enriching rotating disc 7 is divided into an adsorption zone A, a desorption zone B and a cooling zone C by the partition plate 17. The adsorption zone A, the desorption zone B and the cooling zone C are respectively connected with an adsorption channel 8, a cooling channel 9 and a desorption channel 10. The oxygen-enriching material rotating disc 7 is driven to rotate by the driving motor 17, and the rotating speed can be adjusted according to requirements. The two sides of the adsorption zone A of the magnetic oxygen-enriching rotating disc 7 are provided with magnetic field assemblies 22.

[0047] In combination Figure 1 With the working process of the magnetic oxygen-enriching combustion system and method provided by the application as follows: air is first ionized by the air ionization assembly 21 after being pressurized by the combustion air fan 3, and then enters the adsorption zone A of the magnetic oxygen-enriching rotating disc 7 through the adsorption channel 8. Oxygen in the air is adsorbed and enriched by the magnetic medium under the action of the magnetic field formed by the magnetic field assemblies 22 on the two sides of the adsorption zone A, and the remaining air is oxygen-poor (nitrogen-rich) gas, which is discharged through the outlet of the adsorption channel 8. After the magnetic medium in the adsorption zone A adsorbs and enriches the oxygen-enriched gas, the magnetic oxygen-enriching rotating disc 7 is driven to rotate by the driving motor 17, and the magnetic medium is transferred to the desorption zone B. In this area, the magnetic medium loses the magnetic force and releases paramagnetic oxygen gas due to the loss of the external magnetic field. At the same time, the high-temperature flue gas rich in CO2 from the heat exchanger 4 enters the desorption zone B through the desorption channel 10 to heat and further promote the release of oxygen gas, and enters the combustion furnace 15 as combustion air together with the flue gas. After the combustion air and the fuel are combusted in the combustion furnace, the high-temperature flue gas is pressurized by the flue gas circulating fan 6 after heat recovery, and is divided into two paths: the first path 11 enters the dehydration tank 16 for cooling, temperature reduction and dehydration treatment, and the second path 12 is the flue gas rich in CO2, which is discharged from the system and can be further treated for carbon capture or recovery. The magnetic medium releasing oxygen gas after regeneration continues to rotate to the cooling zone C, and at the same time, the low-temperature flue gas treated by the dehydration tank 16 enters the cooling channel 9 of the magnetic oxygen-enriching rotating disc 7 to cool the high-temperature magnetic medium after regeneration. The cooled magnetic medium continues to rotate to the adsorption zone A to continue to adsorb and gather oxygen gas under the action of the magnetic field, and the whole adsorption-desorption magnetic oxygen-enriching cycle process is completed.

[0048] Example 1

[0049] With the working process of the magnetic oxygen-enriching combustion system and method provided by the application as follows: air is first ionized by the air ionization assembly 21 after being pressurized by the combustion air fan 3, and then enters the adsorption zone A of the magnetic oxygen-enriching rotating disc 7 through the adsorption channel 8. Oxygen in the air is adsorbed and enriched by the magnetic medium under the action of the magnetic field formed by the magnetic field assemblies 22 on the two sides of the adsorption zone A, and the remaining air is oxygen-poor (nitrogen-rich) gas, which is discharged through the outlet of the adsorption channel 8. After the magnetic medium in the adsorption zone A adsorbs and enriches the oxygen-enriched gas, the magnetic oxygen-enriching rotating disc 7 is driven to rotate by the driving motor 17, and the magnetic medium is transferred to the desorption zone B. In this area, the magnetic medium loses the magnetic force and releases paramagnetic oxygen gas due to the loss of the external magnetic field. At the same time, the high-temperature flue gas rich in CO2 from the heat exchanger 4 enters the desorption zone B through the desorption channel 10 to heat and further promote the release of oxygen gas, and enters the combustion furnace 15 as combustion air together with the flue gas. After the combustion air and the fuel are combusted in the combustion furnace, the high-temperature flue gas is pressurized by the flue gas circulating fan 6 after heat recovery, and is divided into two paths: the first path 11 enters the dehydration tank 16 for cooling, temperature reduction and dehydration treatment, and the second path 12 is the flue gas rich in CO2, which is discharged from the system and can be further treated for carbon capture or recovery. The magnetic medium releasing oxygen gas after regeneration continues to rotate to the cooling zone C, and at the same time, the low-temperature flue gas treated by the dehydration tank 16 enters the cooling channel 9 of the magnetic oxygen-enriching rotating disc 7 to cool the high-temperature magnetic medium after regeneration. The cooled magnetic medium continues to rotate to the adsorption zone A to continue to adsorb and gather oxygen gas under the action of the magnetic field, and the whole adsorption-desorption magnetic oxygen-enriching cycle process is completed. Figure 1The shown magnetic method oxygen-enriched combustion system carries out combustion treatment on a gas heating furnace of a certain refinery, fuel gas is natural gas, the adsorption area A of the adsorption rotating disc in the system accounts for 1 / 2 of the overall oxygen-enriched material rotating wheel, the desorption area B accounts for 1 / 4 of the overall oxygen-enriched material rotating wheel, and the cooling area C accounts for 1 / 4 of the overall oxygen-enriched material rotating wheel, the magnetic aggregation medium in the oxygen-enriched material rotating wheel is selected from 100 μm iron-chromium alloy steel wool medium, the external magnetic field on both sides of the adsorption area A of the magnetic oxygen-enriched rotating disc is selected from electromagnet, the magnetic field strength is greater than 3T, and the magnetic field gradient is greater than 2000T / m.

[0050] After the air is treated by the air ionization assembly through the combustion-supporting fan 3, the air enters the adsorption area A of the magnetic oxygen-enriched rotating disc 7 through the adsorption channel 8, the oxygen in the air is adsorbed and enriched by the magnetic aggregation medium under the action of the magnetic field formed by the magnetic field assembly 22 on both sides of the adsorption area A, and the remaining air is oxygen-poor gas, which is discharged through the outlet of the adsorption channel 8; after the magnetic aggregation medium in the adsorption area A adsorbs and enriches the oxygen-enriched gas, the magnetic oxygen-enriched rotating disc 7 is rotated by the driving motor 17 and the magnetic aggregation medium is transferred to the desorption area B, in this area, the magnetic aggregation medium loses the magnetic force and releases paramagnetic oxygen gas due to the loss of external magnetic field, at the same time, the high-temperature flue gas rich in CO2 (CO2 volume fraction is about 20%) from the heat exchanger 4 enters the desorption area B through the desorption channel 10 to be heated, further promoting the release of oxygen gas, and entering the combustion furnace 15 as combustion-supporting air together with the flue gas, at this time, the combustion-supporting air has the following component volume fractions: O2 is about 22%, N2 is about 68%, CO2 is about 8%, and the rest is water. After the combustion-supporting air and fuel are combusted in the combustion furnace, the high-temperature flue gas generated is subjected to heat recovery after heat exchange, is pressurized by the flue gas circulating fan 6, and is divided into two paths: the first path accounts for 40% of the total flue gas volume and enters the dehydration tank 16 to be cooled, dehydrated and treated, and the second path is the remaining flue gas which is discharged out of the system, and the CO2 volume concentration of the discharged gas is about 20%, which can be further subjected to carbon capture or recovery treatment; the magnetic aggregation medium which releases oxygen gas after regeneration continues to rotate to the cooling area C, at the same time, the low-temperature flue gas treated by the dehydration tank 16 enters the cooling channel 9 of the magnetic oxygen-enriched rotating disc 7 to cool the high-temperature magnetic aggregation medium after regeneration, and the cooled magnetic aggregation medium continues to rotate to the adsorption area A to continue to adsorb and aggregate oxygen under the action of the magnetic field, completing the entire adsorption-desorption magnetic method oxygen-enrichment cycle process, and the rotating speed of the oxygen-enriched rotating disc is maintained at 3 revolutions / hour.

[0051] Due to the adoption of the magnetic method oxygen-enrichment combined with flue gas circulation and regeneration process optimization, without modification of the original heating furnace burner, the flue gas generation amount is reduced, the flue gas heat loss is reduced, the heating furnace thermal efficiency is improved, and the nitrogen oxide emission can be effectively controlled, compared with the air combustion-supporting process, the flue gas discharge amount is reduced by 43%, and the CO2 concentration in the flue gas is increased from about 10% to 20%, which is equivalent to a reduction of more than 40% in the scale of subsequent carbon capture equipment, greatly reducing the carbon capture cost, and providing convenient conditions for subsequent CO2 capture and recovery.

Claims

1. An oxygen-enriched combustion system, characterized in that, include: Air filter, combustion fan, air ionization assembly, heat exchanger, combustion furnace, flue gas circulation fan, dehydration tank, magnetic field assembly, magnetic oxygen-enriching disc and supporting adsorption channel, cooling channel, and desorption channel; among which... The combustion-supporting blower inlet is open to the atmosphere through a filter; the combustion-supporting blower outlet is connected to the magnetic oxygen-enriching turntable through the adsorption channel inlet after passing through the air ionization component. The outlet of the magnetic oxygen-enriched turntable adsorption channel is connected to the atmosphere. The inlet of the magnetic oxygen-enriched rotary desorption channel is connected to the cold end outlet of the heat exchanger, and the outlet of the magnetic oxygen-enriched rotary desorption channel is connected to the combustion air inlet of the combustion furnace. The inlet of the magnetic oxygen-enriched rotary cooling channel is connected to the gas outlet of the dehydration tank, and the outlet of the magnetic oxygen-enriched rotary cooling channel is connected to the cold end inlet of the heat exchanger. The flue gas outlet of the combustion furnace is connected to the hot end inlet of the heat exchanger. The hot end outlet of the heat exchanger is divided into two paths after passing through the flue gas circulation fan. The first path is connected to the inlet of the dehydration tank, and the second path is discharged out of the system. The magnetic oxygen-enriched turntable consists of an outer shell, an oxygen-enriched material wheel, a partition, and a drive motor. The oxygen-enriched material wheel is filled with a magnetically concentrated medium. The interior of the oxygen-enriched material wheel is divided into an adsorption zone, a desorption zone, and a cooling zone by the partition, and these zones are respectively connected to the adsorption channel, cooling channel, and desorption channel on the outer shell. Magnetic field components are installed on both sides of the adsorption zone of the magnetic oxygen-enriched turntable.

2. The oxygen-enriched combustion system according to claim 1, characterized in that, The dehydration tank is a cooling dehydration gas-liquid separation tank, and is equipped with a refrigerant heat extraction device inside.

3. The oxygen-enriched combustion system according to claim 1, characterized in that, The air ionization component is a plasma generator.

4. The oxygen-enriched combustion system according to claim 3, characterized in that, The air ionization component is a non-equilibrium plasma generator.

5. The oxygen-enriched combustion system according to claim 1, characterized in that, The adsorption zone accounts for 1 / 2 to 3 / 4 of the total oxygen-enriched material rotor magnetic media, the desorption zone accounts for 1 / 4 to 1 / 8 of the total oxygen-enriched material rotor magnetic media, and the cooling zone accounts for 1 / 4 to 1 / 8 of the total oxygen-enriched material rotor magnetic media.

6. The oxygen-enriched combustion system according to claim 1, characterized in that, The oxygen-enriched material wheel is driven by a drive motor to rotate, and the speed can be adjusted according to requirements.

7. The oxygen-enriched combustion system according to claim 1, characterized in that, The magnetic field component consists of multiple sets of magnets, which are permanent magnets, electromagnets, or superconducting magnets.

8. The oxygen-enriched combustion system according to claim 1, characterized in that, The magnetic medium is used to transform a uniform magnetic field within the adsorption region into a non-uniform magnetic field with a high gradient.

9. The oxygen-enriched combustion system according to claim 1, characterized in that, The magnetic concentrator is one or a combination of several of the following: spherical medium, toothed plate medium, mesh medium, rod medium, and steel wool medium; the material of the magnetic concentrator is one or more of the following: pure iron, low carbon steel, ferritic magnetic stainless steel, and iron-cobalt-neodymium-boron alloy.

10. An oxygen-enriched combustion method, employing the oxygen-enriched combustion system according to any one of claims 1-9, characterized in that, Includes the following steps: (1) After being pressurized by the combustion fan, the air is first ionized by the air ionization component to form a non-equilibrium plasma state. Then, it enters the adsorption zone of the magnetic oxygen-enriching turntable through the adsorption channel. The oxygen in the air is adsorbed and enriched by the magnetic medium under the action of the magnetic field components on both sides of the adsorption zone. The remaining air is oxygen-deficient gas and is discharged through the outlet of the adsorption channel. (2) After the magnetic medium in the adsorption zone in step (1) adsorbs and enriches the oxygen-enriched gas, the magnetic oxygen-enriched turntable is driven by the drive motor to rotate and turn the magnetic medium to the desorption zone. The magnetic medium loses its magnetic force and releases paramagnetic gas oxygen. At the same time, the high-temperature flue gas from the heat exchanger enters the desorption zone through the desorption channel for heating, further promoting the release of oxygen, and enters the combustion furnace as combustion air along with the flue gas. (3) After the combustion air and fuel in step (2) are burned in the combustion furnace, the high-temperature flue gas generated is subjected to heat exchange and heat recovery, and then pressurized by the flue gas circulation fan and divided into two paths: the first path enters the dehydration tank for cooling and dehydration treatment, and the second path is discharged from the system. (4) After releasing oxygen in step (2), the magnetic medium continues to rotate to the cooling zone. At the same time, the low-temperature flue gas after being treated by the dehydration tank in step (3) enters the cooling channel of the magnetic oxygen-enriching turntable to cool down the regenerated high-temperature magnetic medium. After cooling, the magnetic medium continues to rotate to the adsorption zone and continues to adsorb and accumulate oxygen under the action of the magnetic field, thus completing the entire magnetic oxygen-enriching cycle process of adsorption-desorption.

11. The oxygen-enriched combustion method according to claim 10, characterized in that, An air filter is installed in front of the combustion fan in step (1) to filter impurities in the air.

12. The oxygen-enriched combustion method according to claim 10, characterized in that, The high-temperature flue gas mentioned in step (2) is CO2-rich flue gas with a CO2 volume concentration higher than 15%.

13. The oxygen-enriched combustion method according to claim 10, characterized in that, The volume concentration of O2 in the combustion air in step (2) is ≥21%.

14. The oxygen-enriched combustion method according to claim 10, characterized in that, The temperature of the dehydration tank in step (3) is 10~60℃.

15. The oxygen-enriched combustion method according to claim 10, characterized in that, In step (3), the first stream of flue gas accounts for 10% to 50% of the total flue gas, and the second stream of flue gas accounts for 50% to 90% of the total flue gas.

16. The oxygen-enriched combustion method according to claim 10, characterized in that, In step (3), the gas from the second external exhaust system is further subjected to carbon capture or recovery treatment.

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