System for preparing oxygen-enriched air under composite conditions of high pressure, low temperature and magnetic field

Abstract

The invention relates to a system for preparing oxygen-enriched air, in particular to a system for preparing oxygen-enriched air under a high-pressure low-temperature and magnetic field composite condition, which is characterized in that an air compressor and an evaporator of the system provide high-pressure low-temperature compressed air, and the compressed air is fed into an air separator with a multi-return-stroke structure for separation; oxygen in air is magnetized in a magnetic field, penetrates through a separation pore plate under the action of magnetic field force and deviates towards one side of a first electromagnet, then compressed air flow forms oxygen-enriched air flow and oxygen-deficient air flow through an adjusting baffle, and the oxygen-enriched air can be fed into combustion equipment to support combustion, so that the combustion efficiency is improved; and oxygen-poor air is fed into the compressed air turbine for energy recovery. The air compressor is main equipment for adjusting oxygen-enriched air flow, and the adjusting baffle and the voltage-adjusting direct-current power supply are main equipment for adjusting oxygen purity. The system is suitable for preparing oxygen-enriched air through combustion equipment, and a new implementation way is provided for low-load stable combustion of the combustion equipment and efficient and clean energy utilization of fuel.

Description

Technical Field

[0001] The invention relates to a system for preparing oxygen-enriched air, and in particular to a system for preparing oxygen-enriched air under the combined conditions of high pressure, low temperature and magnetic field. Background Art

[0002] Oxygen-enriched combustion is a new type of combustion technology. Its core is to burn the fuel in an environment with an oxygen concentration higher than that in the air, thereby obtaining a higher combustion reaction rate and combustion temperature, while also expanding the fuel combustion limit.

[0003] There are many methods for preparing oxygen, such as molecular sieve adsorption, pressure swing adsorption, cryogenic method, membrane oxygen enrichment and water electrolysis. Molecular sieve adsorption has the advantages of high oxygen purity, low power consumption, safety and reliability, but molecular sieves are prone to clogging and the sieve membrane needs to be replaced frequently, which is expensive; pressure swing adsorption has the advantages of mature oxygen production technology, moderate oxygen purity and simple operation, but the equipment investment cost is high, the temperature and humidity requirements of the oxygen production environment are strict, and the adsorbent needs to be replaced regularly; cryogenic method is based on the difference in boiling points of oxygen and nitrogen in the air, and oxygen is separated through compression, cooling and distillation steps. It has the characteristics of high oxygen purity, large production scale and mature technology, but the equipment investment cost is high, the energy consumption is high, and the system pressure resistance requirements are high; membrane oxygen enrichment is to use the different permeation rates of various components in the air through the polymer membrane. Driven by the pressure difference, the oxygen in the air is preferentially passed through the polymer membrane to obtain oxygen-enriched air. It has the advantages of energy saving, environmental protection, wide adaptability and convenient operation, but the polymer membrane is easy to be polluted and clogged, the replacement cost is high, and the purity of oxygen production is limited.

[0004] The use of gradient magnetic fields to produce oxygen is an emerging technology, and there are some related technical reports. Application No. 202210342492.7 "Equipment for extracting oxygen from fluid and its manufacturing method" and Application No. 201410111337.X "Gradient magnetic field assisted cryogenic distillation air separation method and device" disclose a method of separating oxygen from liquid air using a magnetic field. It is a technology that combines cryogenics and magnetic fields. It requires the use of liquid air to prepare oxygen, and the equipment investment cost is high, the energy consumption is high, and the sealing and pressure resistance strength requirements of related pressure vessels and pipelines are high. Summary of the invention

[0005] The purpose of the present invention is to provide a system for preparing oxygen-enriched air under the combined conditions of high pressure, low temperature and magnetic field. The system uses gaseous air to prepare oxygen-enriched air under the combined conditions of high pressure, low temperature and magnetic field, thereby improving the preparation efficiency of oxygen-enriched air. The system can adjust the ratio of oxygen-enriched air to oxygen-depleted air, thereby improving the flexibility of system operation, and uses steam turbines and compressed air turbines to recover the pressure energy of oxygen-depleted air to achieve energy saving and consumption reduction, thereby providing a new development path for low-load stable combustion of energy combustion equipment and efficient and clean utilization of fuel.

[0006] The objective of the present invention is achieved through the following technical solutions: The system for preparing oxygen-enriched air under the combined conditions of high pressure, low temperature and magnetic field of the present invention comprises an air separator, a first electromagnet, a second electromagnet, an evaporator and an air compressor, wherein an oxygen-enriched air regulating baffle is installed on the upper part of the air separator; the first electromagnet and the second electromagnet are perpendicular to the air separator and arranged on both sides of the air separator; the air separator is connected to the evaporator through a pipeline; and the evaporator is connected to the air compressor through a pipeline.

[0007] The magnetic poles of the first electromagnet and the second electromagnet are arranged in the same manner, and the N-level magnetic field of the first electromagnet and the S-level magnetic field of the second electromagnet are located on both sides of the air separator.

[0008] The oxygen-rich air outlet is on the same side as the first electromagnet, and the oxygen-depleted air outlet is on the same side as the second electromagnet.

[0009] The air separator housing is made of non-magnetic steel material.

[0010] The air compressor and the refrigeration compressor are driven by a steam turbine and a compressed air turbine, which are connected by a hydraulic coupling.

[0011] The first electromagnet and the second electromagnet are connected in parallel to the adjustable voltage DC power supply.

[0012] The air separator is connected to the condenser through a pipeline via an oxygen-enriched air outlet.

[0013] The air separator passes through the oxygen-depleted air outlet and is connected to the oxygen-depleted air storage tank and the compressed air turbine through a three-way valve.

[0014] The condenser, evaporator and refrigeration compressor are connected by pipes.

[0015] The oxygen-enriched air storage tank is connected to the boiler combustion equipment through a pipeline.

[0016] The air passage of the air separator adopts a multi-return structure.

[0017] The air separator has vertically arranged partition orifice plates.

[0018] The separation plate is made of non-magnetic steel material.

[0019] The system for preparing oxygen-enriched air under high-pressure, low-temperature and magnetic field composite conditions of the present invention operates as follows: When the load of the boiler combustion equipment is lower than the set value, the output of the air compressor is reduced, the voltage of the adjustable DC power supply is reduced, the opening of the oxygen-enriched air regulating damper is reduced, the oxygen concentration in the oxygen-enriched air storage tank is increased, the combustion stability of the boiler combustion equipment is enhanced, and low-load stable combustion is achieved; when the load of the boiler combustion equipment is higher than the set value, the output of the air compressor is increased, the voltage of the adjustable DC power supply is increased, the opening of the oxygen-enriched air regulating damper is increased, and the amount of oxygen-enriched air required for the combustion of the boiler combustion equipment is provided.

[0020] Preferably, when the load of the boiler combustion equipment is lower than a set value, the compressed air in the oxygen-depleted air storage tank and the oxygen-depleted air flow separated by the air separator are sent to the compressed air turbine to perform work; when the load of the boiler combustion equipment is higher than the set value, the oxygen-depleted air flow separated by the air separator is sent to the oxygen-depleted air storage tank for storage, and when the air storage pressure of the oxygen-depleted air storage tank reaches a limit value, the oxygen-depleted air flow separated by the air separator is directly sent to the compressed air turbine to perform work.

[0021] The positive effects and salient features of the present invention are: 1. The air compressor and evaporator of the system of the present invention provide high-pressure and low-temperature compressed air for the air separator, and there is no need to prepare liquid air. According to Curie's law, the magnetic susceptibility of paramagnetic gas is proportional to the air pressure and inversely proportional to the square of the thermodynamic temperature. Oxygen is a paramagnetic gas, and high-pressure and low-temperature compressed air can increase the magnetic susceptibility of oxygen. At the same time, nitrogen is a diamagnetic gas, and the effect of the magnetic field on the molecular motion of diamagnetic gas is very weak and can be ignored. Therefore, high-pressure and low-temperature conditions can effectively improve the preparation effect of oxygen-enriched air in the gradient magnetic field.

[0022] 2. The air separator of the present invention adopts a multi-return structure, which can increase the flow distance of air in the air separator, thereby improving the preparation efficiency of oxygen-enriched air; the adjustable voltage DC power supply can adjust the magnetic field strength, and the oxygen-enriched air regulating baffle can adjust the ratio of oxygen-enriched air and oxygen-depleted air. These measures can improve the flexibility of the operation of the system.

[0023] 3. The present invention adopts a steam turbine to perform work and adopts a compressed air turbine to recover the pressure energy of oxygen-depleted air, thereby achieving the effect of energy saving and consumption reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a diagram of the oxygen-enriched air preparation system under high-pressure, low-temperature and magnetic field composite conditions of the present invention; Figure 2 It is a side AA cross-sectional view of the air separator of the present invention.

[0025] Numbers in the figure: oxygen-enriched air storage tank outlet 1, oxygen-enriched air storage tank 2, condenser 3, oxygen-enriched air outlet 4, oxygen-enriched air adjustment baffle 5, air separator 6, oxygen-depleted air outlet 7, partition orifice 8, first electromagnet 9, second electromagnet 10, adjustable voltage DC power supply 11, evaporator 12, air compressor 13, air collecting port 14, steam turbine 15, hydraulic coupler 16, compressed air turbine 17, refrigeration compressor 18, three-way valve 19, oxygen-depleted air storage tank 20, boiler combustion equipment 21. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments; based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention. Example

[0027] The air enters the air compressor 13 through the air collecting port 14 for compression and supercharging, and the compressed air enters the evaporator 12 for cooling. The high-pressure and low-temperature compressed air enters the air separator 6 with a multi-return structure for separation. The oxygen in the air is magnetized in the magnetic field and is subjected to the magnetic field force to pass through the partition plate 8 and deviate to the side of the air separator 6 close to the first electromagnet 9. Then, the compressed air flow passes through the oxygen-enriched air regulating baffle 5 to form an oxygen-enriched air flow and an oxygen-depleted air flow. The oxygen-enriched air flow enters the condenser 3 through the oxygen-enriched air outlet 4 for heating and then enters the oxygen-enriched air storage tank 2 for storage. When needed, the oxygen-enriched air is sent to the boiler combustion equipment 21 through the oxygen-enriched air storage tank outlet 1 for combustion assistance, and the oxygen-depleted air flow passes through the oxygen-depleted air outlet 7 and is sent to the oxygen-depleted air storage tank 20 through the three-way valve 19 for energy storage or sent to the compressed air turbine 17 for work. The oxygen-enriched air regulating baffle 5 can adjust the ratio of oxygen-enriched air and oxygen-depleted air by the size of the opening. When a large oxygen-enriched air flow rate is required or the oxygen purity requirement is low, the opening is increased; when a small oxygen-enriched air flow rate is required or the oxygen purity requirement is high, the opening is reduced; The first electromagnet 9 and the second electromagnet 10 are connected in parallel with the adjustable voltage DC power supply 11 to form a gradient magnetic field. The magnetic lines of force are directed from the first electromagnet 9 to the second electromagnet 10. The adjustable voltage DC power supply 11 can adjust the magnetic field strength according to the use demand of oxygen-enriched air. When a large flow rate of oxygen-enriched air is required or the oxygen purity requirement is high, the voltage is increased, and when a small flow rate of oxygen-enriched air is required or the oxygen purity requirement is low, the voltage is reduced; The air compressor 13 is the main equipment for regulating the flow rate of oxygen-enriched air, and the oxygen-enriched air regulating baffle 5 and the voltage-regulated DC power supply 11 are the main equipment for regulating the oxygen purity; The refrigerant is compressed by the refrigeration compressor 18, enters the condenser 3 and exchanges heat with the low-temperature oxygen-rich air flow, and then is sent to the evaporator 12 to evaporate and absorb heat, thereby reducing the temperature of the compressed air, and then the refrigerant returns to the refrigeration compressor 18; The steam drives the steam turbine 15 to rotate, driving the air compressor 13 to do work. The oxygen-depleted air flow drives the compressed air turbine 17 to rotate, driving the refrigeration compressor 18 to do work. The steam turbine 15 and the compressed air turbine 17 are connected through a hydraulic coupler 16 to rotate coaxially.

Claims

1. A system for preparing oxygen-enriched air under high pressure, low temperature and magnetic field conditions, the system comprising an air separator, a first electromagnet, a second electromagnet, an evaporator and an air compressor, characterized in that: An oxygen-enriched air adjustment baffle (5) is installed on the upper part of the air separator (6); the first electromagnet (9) and the second electromagnet (10) are arranged vertically on both sides of the air separator (6); the air separator (6) is connected to the evaporator (12) through a pipeline; the evaporator (12) is connected to the air compressor (13) through a pipeline; the magnetic poles of the first electromagnet (9) and the second electromagnet (10) are arranged in the same way, and the magnetic field of the first electromagnet (9) is of level N and the magnetic field of the second electromagnet (10) is of level S, which are located on both sides of the air separator (6); the oxygen-enriched air outlet (4) is on the same side as the first electromagnet (9), and the oxygen-depleted air outlet (7) is on the same side as the second electromagnet (10); The air compressor (13) and the refrigeration compressor (18) are connected via a steam turbine (15) and a compressed air turbine (17), and the steam turbine (15) and the compressed air turbine (17) are connected via a hydraulic coupler (16); the air separator (6) is connected to the condenser (3) via a pipeline via an oxygen-enriched air outlet (4); the air separator (6) is connected to the oxygen-depleted air storage tank (20) and the compressed air turbine (17) via a three-way valve (19) via an oxygen-depleted air outlet (7); the condenser (3), the evaporator (12) and the refrigeration compressor (18) are connected via a pipeline; and the oxygen-enriched air storage tank (2) is connected to the boiler combustion equipment (21) via a pipeline.

2. The system for preparing oxygen-enriched air under high pressure, low temperature and magnetic field combined conditions according to claim 1, characterized in that: The shell of the air separator (6) is made of non-magnetic steel material.

3. The system for preparing oxygen-enriched air under high pressure, low temperature and magnetic field combined conditions according to claim 1, characterized in that: The first electromagnet (9) and the second electromagnet (10) are connected in parallel to an adjustable voltage DC power supply (11).

4. The system for preparing oxygen-enriched air under high pressure, low temperature and magnetic field combined conditions according to claim 1, characterized in that: The air passage of the air separator (6) adopts a multi-return structure.

5. The system for preparing oxygen-enriched air under high pressure, low temperature and magnetic field combined conditions according to claim 1, characterized in that: The air separator (6) has a partition plate (8) arranged vertically.

6. The system for preparing oxygen-enriched air under high pressure, low temperature and magnetic field combined conditions according to claim 5, characterized in that: The partition plate (8) is made of non-magnetic steel material.

7. The system for preparing oxygen-enriched air under high pressure, low temperature and magnetic field combined conditions according to claim 1, characterized in that: The system operates as follows: a. When the load of the boiler combustion equipment (21) is lower than the set value, the output of the air compressor (13) is reduced, the voltage of the adjustable DC power supply (11) is reduced, and the opening of the oxygen-enriched air regulating damper (5) is reduced to increase the oxygen concentration in the oxygen-enriched air storage tank (2), thereby enhancing the combustion stability of the boiler combustion equipment (21) and achieving low-load stable combustion; b. When the load of the boiler combustion equipment (21) is higher than the set value, the oxygen-depleted air flow separated by the air separator (6) is sent to the oxygen-depleted air storage tank (20) for storage. When the air storage pressure of the oxygen-depleted air storage tank (20) reaches a limited value, the oxygen-depleted air flow separated by the air separator (6) is directly sent to the compressed air turbine (17) to perform work, thereby increasing the output of the air compressor (13), increasing the voltage of the adjustable DC power supply (11), and increasing the opening of the oxygen-enriched air regulating damper (5), thereby providing the oxygen-enriched air required for combustion of the boiler combustion equipment (21).

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