JPS62216904A - Pressure type medical oxygen concentrator - Google Patents

Abstract

PURPOSE:To obtain sanitary oxygen-enriched air which is medically required and temporarily humidified by communicating the exhaust system of a separation membrane module with the cooling system of a cooler through an expansion valve, and controlling the cooling temp. CONSTITUTION:The air sucked by the action of a primary air compressor 2 through the primary air filter 1 is cooled by a gas cooler 3. The contained water is separated in a drain separator 4, and then the air is supplied under pressure to the primary side of the gas separation membrane module 5 provided with a separation membrane. the air passing through the separation membrane is enriched in oxygen, and the temp. is lowered due to adiabatic expansion. The air not passing through the separation membrane is supplied to the gas cooler 3 through the expansion valve 6 to cool the untreated gas, and then discharged. Since a vacuum pump and a drain separator are not fitted on the secondary side of the gas separation membrane module 5 in this device, there is no danger of the sterilized air after passing through the clean separation membrane being contaminated.

Description

Detailed Description of the Invention (A) Industrial Application Field The present invention includes a filter, a cooler, a drain water separator, and a gas separation membrane module, and processes air to produce oxygen-enriched air. This invention relates to a medical oxygen concentrator that exhausts other substances.

(b) Conventional Technology Medical oxygen concentrators, which utilize gas separation membranes to produce oxygen-enriched air and supply this to patients, have recently become widely used.

As shown in FIG. 4, the conventional device includes a primary air fan,
It is equipped with a separation membrane module, a vacuum pump, a cooler, a drain water separator, a permeable air filter, and a secondary drain water separator.

The primary air filter 1 is activated by the action of the primary air fan 12.
The air sucked through the gas separation membrane module 1
It is supplied to the primary side of 30 at approximately atmospheric pressure, passes through the separation membrane 13a, and is sucked at a pressure of 9.0.2 to 0.3 ata by the vacuum pump 14 connected to the secondary side. The oxygen-enriched air that has passed through the separation membrane 13a is cooled in the gas cooler 15 by the air (exhaust air) that has not passed through the separation membrane 13a. The cooled oxygen-enriched air is dehydrated in a drain water separator 16, and the mist contained therein is finally removed in a permeable air filter 17 and a secondary drain water separator 18, and then supplied to the patient. .

In order to remove contamination, filters that use activated carbon or the like are often installed.

eC Problems to be solved by the invention As mentioned above,
In the conventional medical oxygen concentrator, the oxygen-enriching gas separation membrane 13a has a high permeation rate for both oxygen and moisture, so the moisture concentration on the secondary side is high. Further, it is inevitable that the temperature on the secondary side increases due to adiabatic compression in the pressure reducing pump 14.

For this reason, the gas that has passed through the secondary side of the gas separation membrane module 130 is cooled using the exhaust air on the primary side before being supplied to the patient, and is further processed in the filter 17 and the secondary drain water separator 18. It is necessary to separate mist, etc.

Therefore, in the conventional device as described above, (1) there is a risk that the sterile oxygen-enriched air that has been obtained through the effort will be contaminated because there is a pressure reduction pump, drain water separator, etc. on the secondary side of the gas separation membrane module; There is sex.

(2) Since the vacuum pump is in an atmosphere of high oxygen and mist generation, the diaphragm in the pump parts is easily damaged or worn out, causing problems in durability.

(3) The drain water separator is a low-pressure type and is highly affected by atmospheric humidity, which can cause problems such as not operating when needed, and can also cause bacterial contamination.

(4) The permeable air filter is easily clogged by mist,
It also needs to be replaced frequently.

(5) Cooling by exhaust air can only achieve a dew point close to atmospheric humidity, and further condensation may occur before the permeated air reaches its intended use, resulting in drainage. (The relative humidity %RH on the secondary side may be 100% in high humidity atmosphere.)

It is an object of the present invention to provide an oxygen concentrator which does not have the above-mentioned drawbacks and is particularly capable of obtaining oxygen-enriched air with a sanitary temporary humidity required for medical use.

(b) Means and action for solving the problems The present invention provides: 1
After the downstream air is cooled in advance to remove moisture, it is supplied to the gas separation membrane module under pressure, while the supplied air is The gas composition on the primary side can be kept constant, and the oxygen concentration and H20 concentration of the permeated air on the secondary side can both be controlled to be constant.

As a result, the cause of contamination of the permeated air on the secondary side is completely eliminated. Furthermore, since the permeated air humidity can be prevented from becoming excessive, a secondary drain water separator near the patient is not required.

(e) Embodiment The embodiment of the present invention shown in FIG. It is equipped with a drain water separator that separates drain water from the drain water separator, and a separation membrane module that obtains oxygen-enriched air from the gas that has passed through the drain water separator.

According to the present invention, in order to cool the pressurized air, the air that has not passed through the separation membrane module is expanded in the expansion valve and used at a low temperature.

That is, the air sucked through the primary air filter A1 by the action of the primary air compressor 2 is cooled in the gas cooler 3, and the water contained is drained into the water separator 4.
After being separated at , it is supplied under pressure to the primary side of a gas separation membrane module 5 equipped with a separation membrane 5a. Separation membrane 5a
The air passing through becomes enriched with oxygen and its temperature decreases due to adiabatic expansion. On the other hand, air that has not passed through the separation membrane 5a (non-permeable gas) is supplied to the gas cooler 3 through the expansion valve 6, and is discharged after cooling the untreated gas.

The above operation will be explained using the water vapor saturation characteristic curve diagram shown in FIG.

In FIG. 2, the point φ indicates the state of the atmosphere.

In the conventional device, since the water permeability in the separation membrane is high, the partial pressure of water passes through the saturation curve P under atmospheric pressure from point φ and reaches point 1. It is then cooled (by the atmosphere) and finally reaches the state at point 2.

In the apparatus of the present invention, the point φ is first compressed to the state of point 5. By passing from point 5 through expansion valve 6,
Non-permeable gas whose temperature has decreased (at this time, the temperature Tx in Figure 2
), the primary side temperature reaches Tr and reaches point 6 on the saturation curve under pressure, producing condensate. Next, the water reaches point 7 due to heat absorption in the piping after drain separation, and further passes through the separation membrane, increasing the partial pressure of water to point 8. Nevertheless, the partial pressure of water is lower than point 2 in the conventional case. If the temperature Tr after expansion is set in accordance with the water concentration characteristics of the membrane, the temperature conditions at points 5 and 8 can be kept constant. That is, it can be set below the saturation point.

Next, FIG. 3 shows a concrete example of the present invention.

The primary air compressor 2 is 15 NJ/min,
The gas cooler 3a, which has a capacity of 200 W and is further arranged between the compressor and the cooler 30, has a diameter of 8φ and a length of 2.
The door is made of Cu tube. The drain water separator 4 is of an automatic discharge type. As the separation membrane 5a, a gas separation membrane made of a silicon-based polymer thin film was used. The opening degree of the expansion valve 6 is controlled according to the temperature on the discharge side of the cooler 3.

When air at 22°C is inhaled, the temperature of the air that exits the cooler 3a is 47°C.It is cooled by the cooler 3, and after passing through the drain water separator 4, it reaches the separation membrane module at a temperature of 16°C. 5
31% of oxygen-enriched air (0□% 40%) is obtained per minute. As mentioned above, oxygen-enriched air was heated to 90% RH (a
t20°C), the primary side cooling temperature should be set to 15°C.
Must be kept at ℃. On the other hand, the air that did not pass through the membrane 5a (exhaust air) was heated to 12 N! at 18°C. I/mi
It reaches the expansion valve 6 in increments of n, but by appropriately determining the opening degree of the valve, it is cooled to 2°C, and then passed through the cooler 3 to reduce the temperature to 3°C.
The temperature rises to 2°C and is discharged.

(F) Effects of the Invention As configured as described above, the present invention has the following effects.

■ Since there are no vacuum pumps, drain separators, etc. on the secondary side of the separation membrane module, there is no risk of contamination of the sterile air that has passed through the clean separation membrane.

■ Since a primary air compressor is used instead of a pressure reducing pump, there is no risk of pump failure.

■ No drain separator is required downstream of the separation membrane;
This is unrelated to the drain water separator malfunction caused by atmospheric humidity.

■ Because it is not equipped with a permeable air filter.

No clogging of flow path.

■ Since the expansion valve is provided, the non-permeable gas is sufficiently cooled, so that drain water can be completely removed.

[Brief explanation of drawings]

FIG. 1 is a diagrammatic configuration diagram of an embodiment of the present invention. FIG. 2 is a detailed diagram illustrating the present invention using saturation curves for water vapor temperature and pressure. FIG. 3 is a diagram showing a specific example of the present invention. tg4 is a diagram similar to FIG. 1 showing a conventional device. 1. Primary air filter 2. Primary air compressor 3... Gas cooler 411. Drain water separator 591
1 separation membrane module 5a-.0 separation membrane 61. ．． expansion valve

Claims (1)

[Claims] 1. A compressor that adiabatically compresses intake air to supply pressurized air, a cooler that cools the pressurized air, a drain water separator that separates drain from the cooled pressurized air, and a drain water separator. a separation membrane module that obtains oxygen-enriched air from the gas that has passed through the device, the cooler is disposed immediately before the drain water separator, and the exhaust system of the separation membrane module and the cooling system of the cooler are connected. , a pressurized medical oxygen concentrator characterized in that conduction is conducted through an expansion valve with adjustable cooling temperature.