Molecular sieve oxygen generation system and oxygen generation method

Abstract

The invention belongs to the technical field of medical instruments, and particularly relates to a molecular sieve oxygen generation system and an oxygen generation method. The system comprises an air compressor, a radiator, a gas-water separator and an air tank which are sequentially connected and then is divided into two paths, one path enters an instrument gas tank through a one-way valve, the other path enters an oxygen generation main machine, and the oxygen generation main machine comprises an air inlet loop and an exhaust loop which are arranged before entering two adsorption towers with the same structure, and a pressure equalizing loop and a cleaning loop which are arranged after entering the two adsorption towers; the device is characterized in that an adsorbent and a molecular sieve are placed in each adsorption tower, the adsorbent is located on the lower portion of the adsorption tower, the molecular sieve is located on the upper portion of the adsorption tower, the adsorbent is used for adsorbing moisture in air entering the adsorption tower so as to remove water, and the cleaning loop is provided with a cleaning throttling hole. The number of valves in the oxygen generating main machine and oxygen generating steps are reduced while the oxygen concentration is guaranteed, so that the structure of the oxygen generating main machine is more compact; the all-in-one design of the oxygen generation system is facilitated, and the oxygen generation effect of the molecular sieve is further improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to a molecular sieve oxygen production system and an oxygen production method. Background Art

[0002] Molecular sieve oxygen production system is a common industrial oxygen production equipment that realizes nitrogen and oxygen separation through the molecular sieve adsorption principle. Its working principle is that the raw air is pressurized by the compressor, passes through the air pretreatment device to remove solid impurities such as oil and dust and water, and then enters the adsorption tower equipped with molecular sieves, and nitrogen, carbon dioxide, etc. in the air are adsorbed to obtain high-purity oxygen.

[0003] In order to ensure continuous and stable oxygen production in pressure swing adsorption at the current stage, two adsorption towers need to be set up. When one of the adsorption towers is in the decomposition state, the oxygen tank cleans it through the valve body, so that the adsorption tower in the decomposition state further exhausts nitrogen. However, this requires the installation of a separate cleaning pipeline and a corresponding valve body between the oxygen tank and the adsorption tower. Such a design structure is complex and increases the size of the equipment.

[0004] At the same time, in the oxygen production process of the existing oxygen generator, a refrigerated dryer is used to remove moisture from the air, but the refrigerated dryer needs to be set up separately from the air compressor, which increases the installation space and power consumption of the integrated equipment and also makes the steps of the oxygen production method complicated. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and to provide a molecular sieve oxygen production system and an oxygen production method.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a molecular sieve oxygen production system, comprising an air compressor, a radiator, an air-water separator and an air tank connected in sequence and then divided into two paths, one path enters the instrument gas tank through a one-way valve, and the other path enters the oxygen production main unit, the oxygen production main unit includes an intake circuit and an exhaust circuit before entering two adsorption towers with the same structure, and then a pressure equalization circuit and a cleaning circuit are arranged; an adsorbent and a molecular sieve are placed in each of the adsorption towers, the adsorbent is located at the lower part of the adsorption tower, and the molecular sieve is located at the upper part of the adsorption tower, the adsorbent is used to adsorb the moisture of the air entering the adsorption tower to remove water, and the cleaning circuit is provided with a cleaning throttle hole.

[0007] Preferably, the air intake circuit includes air intake valves 1A and 1B connected in sequence, the exhaust circuit includes exhaust valves 2A and 2B connected in sequence, the pressure equalizing circuit includes a pressure equalizing valve 3A, and the two adsorption towers with the same structure include Tower A and Tower B.

[0008] Preferably, the molecular sieve and the adsorbent are separated by a partition, and filter cotton is placed on both sides of the partition.

[0009] Preferably, the radiator is a two-stage radiator, and a two-stage filter is arranged after the air tank.

[0010] Preferably, the gas entering the instrument gas tank passes through the pressure reducing filter valve and the connecting valve plate in sequence.

[0011] Preferably, the oxygen output by the oxygen generator enters the oxygen buffer tank through a one-way valve, and the oxygen buffer tank is sequentially connected to a pressure reducing valve and a first ball valve, and the first ball valve is used to adjust the gas production.

[0012] Preferably, a sampling port and an unqualified gas discharge valve are respectively provided on both sides of the first ball valve. The oxygen concentration is monitored through the sampling port, and unqualified gas is discharged through the unqualified gas discharge valve. The qualified gas enters the oxygen tank after passing through the booster, solenoid valve and one-way valve in sequence.

[0013] Preferably, a pressure gauge is arranged between the oxygen tank and the one-way valve for detecting the outlet pressure, and a second ball valve and a mass flow meter are connected in sequence behind the oxygen tank, wherein the second ball valve is used to control the oxygen outlet flow of the oxygen tank, and the mass flow meter is used to monitor the oxygen production flow in real time.

[0014] Preferably, the unqualified gas discharge valve adopts a two-position three-way valve. When the oxygen concentration is unqualified, the two-position three-way valve is switched, and one path connected to the booster is switched to a closed state, and the other path is connected to the cleaning circuit, and the oxygen with unqualified oxygen concentration is blown into the adsorption tower as regeneration gas.

[0015] On the other hand, the present invention provides a molecular sieve oxygen production method, which is implemented based on the above molecular sieve oxygen production system, and the method includes: a pressure equalization stage and an air intake oxygen production stage performed in a cycle;

[0016] Open the pressure equalizing valve 3A, and close the air inlet valves 1A and 1B and the exhaust valves 2A and 2B, then the pressure of tower B rises and the pressure of tower A drops; when the pressures of the two towers meet the first threshold, the pressure equalizing stage ends and tower B enters the air intake and oxygen production stage;

[0017] Close the pressure equalizing valve 3A, open the air inlet valve 1B and the exhaust valve 2A, and the pressure of tower B rises, and the nitrogen in tower A is discharged to the outside. When the pressure of tower B reaches the second threshold and the pressure of tower A is 0, the air intake and oxygen production stage of tower B ends and enters the pressure equalization stage.

[0018] Open the pressure equalizing valve 3A, and close the air inlet valves 1A and 1B and the exhaust valves 2A and 2B, then the pressure of tower A rises and the pressure of tower B drops; when the pressures of the two towers meet the first threshold, the pressure equalizing stage ends and tower A enters the air intake and oxygen production stage;

[0019] When the pressure equalizing valve 3A is closed and the air inlet valve 1A and the air exhaust valve 2B are opened, the pressure of tower A rises and the nitrogen in tower B is discharged to the outside. When the pressure of tower A reaches the second threshold and the pressure of tower B is 0, the air intake and oxygen production stage of tower A ends and a cycle is completed.

[0020] Compared with the prior art, the advantages of the present invention are:

[0021] 1. The system of the present invention arranges a cleaning loop between the adsorption towers and adopts a cleaning throttle hole in the cleaning loop, thereby reducing the number of valves and oxygen production steps in the oxygen generator while ensuring the oxygen concentration, making the structure of the oxygen generator more compact;

[0022] 2. The system of the present invention integrates the adsorbent into the separator to achieve the effect of removing water from the air, eliminates the refrigeration dryer, simplifies the structural composition of the oxygen production system, and is conducive to the realization of the integrated design of the oxygen production system.

[0023] 3. The system of the present invention can connect the unqualified external valve to the adsorption tower through a pipeline to achieve the cleaning of the adsorption tower at the same time as the cleaning pipeline. That is, when the purity of the generated oxygen is unqualified, it can be directly blown into the adsorption tower as regeneration gas, thereby playing a good energy-saving role and further improving the oxygen production effect of the molecular sieve. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a system composition diagram of the present invention;

[0025] Figure 2 yes Figure 1 A partial enlarged view of the oxygen generator host;

[0026] Figure 3 It is a schematic diagram of the structure of the oxygen generator host in the prior art;

[0027] Figure 4 yes Figure 3 Table showing the corresponding steps;

[0028] Figure 5 It is a schematic diagram of the internal structure of the adsorption tower. DETAILED DESCRIPTION

[0029] The present invention reduces the number of cleaning valves in the oxygen production main unit, simplifies the steps of the oxygen production method, removes the refrigeration dryer, and simplifies the structure of the entire oxygen production system.

[0030] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0031] Example 1

[0032] Embodiment 1 of the present invention proposes a molecular sieve oxygen production system. The specific structure is as follows Figure 1As shown. The molecular sieve oxygen production system includes an air compressor, a radiator, an air-water separator and an air tank connected in sequence and then divided into two paths, one path enters the instrument gas tank through a one-way valve, and the other path enters the oxygen production host. The oxygen production host includes an intake circuit and an exhaust circuit before entering two adsorption towers with the same structure, and then a pressure equalization circuit and a cleaning circuit are set; it is characterized in that an adsorbent and a molecular sieve are placed in each of the adsorption towers, the adsorbent is located at the lower part of the adsorption tower, and the molecular sieve is located at the upper part of the adsorption tower. The adsorbent is used to adsorb the moisture in the air entering the adsorption tower to remove water, and the cleaning circuit is provided with a cleaning throttle hole. Specifically:

[0033] The air compressor compresses the air and passes through a two-stage radiator to reduce the temperature of the air. The air passes through an air-water separator to remove moisture from the air. After entering the air tank, in order to stabilize the intake pressure, stabilize the gas source of the oxygen generator. After passing through the secondary filter, it is divided into two paths. One path enters the instrument gas tank (not shown in the figure) through a one-way valve. The gas in the instrument gas tank enters the connecting valve plate through the filter pressure reducing valve to supply gas to the pneumatic valve of the oxygen generator. The other path enters the oxygen generator for oxygen production. The oxygen produced by the oxygen generator enters the oxygen buffer tank through a one-way valve. The oxygen buffer tank passes through a ball valve after the pressure reducing valve, and the ball valve can adjust the gas production. Sampling ports and unqualified gas discharge valves are respectively provided on both sides of the ball valve. In order to realize the selection of external discharge into the air or into the booster by monitoring the oxygen concentration. The booster is used to pressurize the oxygen. The pressure relief valve is connected to the booster. The pressure relief valve is used to relieve the pressure of the booster to prevent the booster from starting under pressure. After the booster, it enters the oxygen tank through a one-way valve. A pressure gauge is connected between the pipeline between the oxygen tank and the booster to detect the outlet pressure. A ball valve is connected after the oxygen tank to control the oxygen outlet flow of the oxygen tank. A mass flow meter is connected after the ball valve to monitor the oxygen production flow in real time.

[0034] The pipeline structure of the oxygen generator (the one in the dotted box) is composed of an air intake circuit, an exhaust circuit, a pressure equalization circuit, and a cleaning circuit. Pneumatic valves are installed on the air intake circuit, the exhaust circuit, and the pressure equalization circuit, and the pneumatic valves are controlled by the air circuit on the connecting valve plate. A cleaning throttle hole is installed on the cleaning circuit to achieve oxygen cleaning between adsorption towers A and B. Figure 2 As shown, the corresponding valve in the cleaning circuit is cancelled. The throttle hole can be a fixed pipe with a diameter smaller than the loop pipeline or other methods that can reduce the diameter of the loop channel, including a throttle valve, a speed regulating valve, a ball valve, etc. In the embodiment of the present invention, the oxygen flow rate is changed by fixing a round steel with a small hole in the pipeline. After the pneumatic valve in the cleaning circuit is replaced with a throttle hole, the amount of oxygen used for cleaning is controlled, the oxygen production of the oxygen generator is guaranteed, and the pressure difference in the two adsorption towers is maintained.

[0035] Adsorbent and molecular sieve are placed inside the adsorption tower. Figure 5As shown, the adsorbent is located at the lower part of the adsorption tower, and the molecular sieve is located at the upper part of the adsorption tower. A partition is used to separate the adsorbent and the molecular sieve. Filter cotton is placed on both sides of the partition to further improve the separation between the molecular sieve and the adsorbent to avoid mixing between the two. The adsorbent is used to absorb moisture entering the adsorption tower. The type of adsorbent is not limited. In some embodiments, the adsorbent is alumina. A partition and filter cotton are between the molecular sieve and the adsorbent. The adsorbent is used to absorb moisture from the air entering the adsorption tower.

[0036] Example 2

[0037] Embodiment 2 of the present invention provides a molecular sieve oxygen production method, which is implemented based on the molecular sieve oxygen production system of embodiment 1, and the method includes: a pressure equalization stage and an air intake oxygen production stage performed in a cycle;

[0038] Open the pressure equalizing valve 3A, and close the air inlet valves 1A and 1B and the exhaust valves 2A and 2B, then the pressure of tower B rises and the pressure of tower A drops; when the pressures of the two towers meet the first threshold, the pressure equalizing stage ends and tower B enters the air intake and oxygen production stage;

[0039] Close the pressure equalizing valve 3A, open the air inlet valve 1B and the exhaust valve 2A, and the pressure of tower B rises, and the nitrogen in tower A is discharged to the outside. When the pressure of tower B reaches the second threshold and the pressure of tower A is 0, the air intake and oxygen production stage of tower B ends and enters the pressure equalization stage.

[0040] Open the pressure equalizing valve 3A, and close the air inlet valves 1A and 1B and the exhaust valves 2A and 2B, then the pressure of tower A rises and the pressure of tower B drops; when the pressures of the two towers meet the first threshold, the pressure equalizing stage ends and tower A enters the air intake and oxygen production stage;

[0041] When the pressure equalizing valve 3A is closed and the air inlet valve 1A and the air exhaust valve 2B are opened, the pressure of tower A rises and the nitrogen in tower B is discharged to the outside. When the pressure of tower A reaches the second threshold and the pressure of tower B is 0, the air intake and oxygen production stage of tower A ends and a cycle is completed.

[0042] Specifically, the method of oxygen generator (fast oxygen production): It is divided into two cycles, each cycle includes two steps: 1. Pressure equalization. 2. Air intake and oxygen production. Pressure equalization stage: Only the pressure equalization valve is opened, and the air intake valve and the exhaust valve are closed. The pressure moves from the high-pressure side to the low-pressure side. Air intake and oxygen production stage: The air intake valve and the exhaust valve are opened. The pressure equalization valve is closed. See Table 1 for a diagram. The pressure equalization and air intake time are determined according to the pressure in the adsorption tower. The pressure equalization time can be set to t1, and the air intake time can be set to t2. Take the oxygen production of tower B as an example: Pressure equalization stage: The pressure equalization valve 3A is opened for t1, and the air intake valve and the exhaust valve are closed. The pressure of tower B rises, and the pressure of tower A drops. Air intake and oxygen production stage: The pressure equalization valve is closed, the air intake valve 1B is opened, the pressure of tower B rises, the exhaust valve 2A is opened, and the nitrogen in tower A is discharged to the outside. The pressure of tower B rises, and the pressure in tower A drops to zero. Then start the next cycle. In one embodiment, t1 may be 1.8 seconds, and t2 may be 13.5 seconds. This is for illustration only and is not a limitation. The specific duration is determined according to the pressure in the adsorption tower.

[0043] Table 1

[0044]

[0045] like Figure 3 As shown, in the prior art oxygen production, SV05 and SV06 are additional oxygen production valves, and SV09 and SV10 are cleaning valves.

[0046] The oxygen production method is divided into 9 steps in one cycle, which is 7 more steps than the oxygen production method of the present application in a single cycle.

[0047] Oxygen production in Tower A: Pressure equalization stage: Pneumatic valve SV07 is turned on, and the oxygen in Tower B flows to Tower A.

[0048] Feed and exhaust stage: pneumatic valve SV01 is connected, and air enters the upper part of Tower A; pneumatic valve SV04 is connected, and nitrogen is discharged from the upper part of Tower B, and the nitrogen is discharged from the oxygen generator through the muffler; pneumatic valve SV09 is connected, and the oxygen in the oxygen tank enters Tower A.

[0049] Feeding and oxygen production stage: pneumatic valve SV01 is connected, air enters the upper part of tower A, pneumatic valve SV04 is connected, nitrogen is discharged from the upper part of tower B, and the nitrogen is discharged from the oxygen generator through the muffler; pneumatic valve SV05 is connected, and the lower part of tower A transports oxygen to the oxygen tank.

[0050] Oxygen production and cleaning stage: pneumatic valve SV01 is connected, air enters the upper part of tower A; pneumatic valve SV04 is connected, nitrogen is discharged from the upper part of tower B, and the nitrogen is discharged from the oxygen generator through the muffler; pneumatic valve SV05 is connected, and the lower part of tower A delivers oxygen to the oxygen tank; pneumatic valve SV10 is connected, and the oxygen in the oxygen tank enters tower B. The injected oxygen increases the release of nitrogen in tower B, completing the cleaning of tower B. See the pneumatic valve action for details. Figure 4 .

[0051] Invention point:

[0052] 1. The cleaning throttle hole is used to replace the pneumatic valve used for cleaning, which simplifies the process steps of oxygen production and reduces the number of pressure reducing valves.

[0053] 2. Integrate adsorbents such as alumina into the separator to achieve the effect of removing water from the air, replacing the refrigerated dryer.

[0054] 3. The unqualified exhaust valve can be connected to the adsorption tower through a pipeline to clean the adsorption tower at the same time as the cleaning pipeline. That is, when the purity of the generated oxygen is unqualified, it can be directly blown into the adsorption tower as regeneration gas, thereby playing a good energy-saving role and further improving the oxygen production effect of the molecular sieve.

[0055] like Figure 2 As shown, the unqualified external discharge valve adopts a two-position three-way valve. When the oxygen concentration is unqualified, the two-position three-way valve is switched, and one way connected to the booster is switched to a closed state, and the other way is connected to the cleaning circuit through the three-way connection of the unqualified gas external discharge cleaning circuit. Oxygen with an unqualified concentration can be used as regeneration gas to be blown into the adsorption tower, avoiding the waste caused by direct discharge of unqualified oxygen.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention and should be included in the scope of the claims of the present invention.

Claims

1. A molecular sieve oxygen production system, comprising an air compressor, a radiator, a gas-water separator and an air tank connected in sequence, which are then divided into two paths, one path entering the instrument gas tank through a one-way valve, and the other path entering the oxygen production host, wherein the oxygen production host includes an air intake circuit and an exhaust circuit before entering two adsorption towers with the same structure, and then a pressure equalization circuit and a cleaning circuit; characterized in that: An adsorbent and a molecular sieve are placed in each of the adsorption towers. The adsorbent is located at the lower part of the adsorption tower, and the molecular sieve is located at the upper part of the adsorption tower. The adsorbent is used to adsorb moisture in the air entering the adsorption tower to remove water. The cleaning circuit is provided with a cleaning throttle hole.

2. The molecular sieve oxygen production system according to claim 1, characterized in that: The air intake circuit includes air intake valves 1A and 1B connected in sequence, the exhaust circuit includes exhaust valves 2A and 2B connected in sequence, the pressure equalizing circuit includes a pressure equalizing valve 3A, and two adsorption towers with the same structure include Tower A and Tower B.

3. The molecular sieve oxygen production system according to claim 2, characterized in that: The molecular sieve and the adsorbent are isolated by a partition, and filter cotton is placed on both sides of the partition.

4. The molecular sieve oxygen production system according to claim 2, characterized in that: The radiator is a two-stage radiator, and a two-stage filter is arranged after the air tank.

5. The molecular sieve oxygen production system according to claim 2, characterized in that: The gas entering the instrument gas tank passes through the pressure reducing filter valve and the connecting valve plate in sequence.

6. The molecular sieve oxygen production system according to claim 2, characterized in that: The oxygen output by the oxygen generator enters the oxygen buffer tank through a one-way valve, and the oxygen buffer tank is connected to a pressure reducing valve and a first ball valve in sequence, and the first ball valve is used to adjust the gas production.

7. The molecular sieve oxygen production system according to claim 6, characterized in that: A sampling port and an unqualified gas discharge valve are respectively arranged on both sides of the first ball valve. The oxygen concentration is monitored through the sampling port, and unqualified gas is discharged through the unqualified gas discharge valve. The qualified gas enters the oxygen tank after passing through the booster, solenoid valve and one-way valve in sequence.

8. The molecular sieve oxygen production system according to claim 7, characterized in that: A pressure gauge is arranged between the oxygen tank and the one-way valve for detecting the outlet pressure. A second ball valve and a mass flow meter are connected in sequence behind the oxygen tank, wherein the second ball valve is used to control the oxygen outlet flow of the oxygen tank, and the mass flow meter is used to monitor the oxygen production flow in real time.

9. The molecular sieve oxygen production system according to claim 7, characterized in that: The unqualified gas discharge valve adopts a two-position three-way valve. When the oxygen concentration is unqualified, the two-position three-way valve is switched, and one way connected to the booster is switched to a closed state, and the other way is connected to the cleaning circuit, and the oxygen with unqualified oxygen concentration is blown into the adsorption tower as regeneration gas.

10. A molecular sieve oxygen production method, implemented based on the molecular sieve oxygen production system according to any one of claims 2 to 9, the method comprising: The cycle proceeds through the pressure equalization phase and the air intake and oxygen production phase; Open the pressure equalizing valve 3A, and close the air inlet valves 1A and 1B and the exhaust valves 2A and 2B, then the pressure of tower B rises and the pressure of tower A drops; when the pressures of the two towers meet the first threshold, the pressure equalizing stage ends and tower B enters the air intake and oxygen production stage; Close the pressure equalizing valve 3A, open the air inlet valve 1B and the exhaust valve 2A, and the pressure of tower B rises, and the nitrogen in tower A is discharged to the outside. When the pressure of tower B reaches the second threshold and the pressure of tower A is 0, the air intake and oxygen production stage of tower B ends and enters the pressure equalization stage. Open the pressure equalizing valve 3A, and close the air inlet valves 1A and 1B and the exhaust valves 2A and 2B, then the pressure of tower A rises and the pressure of tower B drops; when the pressures of the two towers meet the first threshold, the pressure equalizing stage ends and tower A enters the air intake and oxygen production stage; When the pressure equalizing valve 3A is closed and the air inlet valve 1A and the air exhaust valve 2B are opened, the pressure of tower A rises and the nitrogen in tower B is discharged to the outside. When the pressure of tower A reaches the second threshold and the pressure of tower B is 0, the air intake and oxygen production stage of tower A ends and a cycle is completed.

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