JPH0242764B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that efficiently obtains oxygen-rich air from the atmosphere using a selectively permeable membrane that allows oxygen to permeate at a higher rate than nitrogen, and is particularly suitable for medical use. Regarding membrane method oxygen enrichers suitable for

In recent years, many patients have been suffering from respiratory system diseases such as asthma, emphysema, and chronic bronchitis, and oxygen inhalation is one of the most effective treatments for these diseases.

However, when inhaling air with a high oxygen concentration of 60% or more in this oxygen inhalation method, it is known that it can be harmful, causing pneumonia symptoms and neurological disorders, etc., rather than having a therapeutic effect. 50% or less is generally used as it is safe.

Currently, most oxygen sources are supplied using pure oxygen obtained by cryogenic separation, packed in cylinders, etc.; however, pure oxygen gas is mixed and diluted with air to reach the desired oxygen concentration. Strict management is required, such as lowering the pressure, monitoring oxygen depletion, and handling of high-pressure cylinders, and replacement and transportation are complicated. Therefore, this method is difficult to use especially in a general household.

On the other hand, as a method for separating and concentrating oxygen in the atmosphere, an adsorption separation method using an adsorbent such as zeolite that adsorbs nitrogen more selectively than oxygen is known. Medical oxygen enrichers using this adsorption separation method have recently been developed, but due to the need for air to be adsorbed and released by the adsorbent, the operating pressure is a so-called pressure swing method in which pressurization and depressurization are repeated. The noise is loud and the noise repeats getting louder and quieter, making the user, especially the sick, feel distressed.

In addition, the adsorption properties deteriorate, and the life of the adsorption method is relatively short.Furthermore, the oxygen concentration obtained by this adsorption method is generally high oxygen concentration air of 50 to 90%. Additionally, the adsorbent absorbs more water vapor, so
The air that comes out is dry and requires humidification for inhalation therapy.

Therefore, oxygen-enriched air is obtained continuously from the air, and the enriched air is safe even if inhaled for a long time.
It would be extremely desirable for patients with long-term respiratory organ disorders if a compact oxygen enricher with an oxygen concentration of 50% or less, low noise, and durability could be developed.

As an oxygen enricher that meets these requirements, an enricher using a membrane method using a selective oxygen permeable membrane that can permeate oxygen at a higher rate than nitrogen has been proposed (for example, Japanese Patent Laid-Open No. 51-6876, Japanese Unexamined Patent Publication 1977-
(See Publication No. 5291).

The characteristics of the oxygen enricher using this membrane method are that the selectivity of oxygen and nitrogen of the membrane is generally in the range of 2 to 5, so the nitrogen concentration obtained by general air separation is 50% or less; Since the permeation of water vapor is greater than that of nitrogen, the enriched air obtained by passing through the membrane comes out humidified, so no humidification is required during inhalation, and the membrane itself is a super filter, so it is free from dust and dirt. Depressurized membrane oxygen enrichers are suitable for medical use because they provide clean air that is completely free of bacteria, and when the operating pressure is reduced only, i.e., when a vacuum pump is used, a low-noise enricher can be created. It can be said to be the most suitable enrichment device.

An even more important point is that in conventional enrichers, the temperature of the oxygen-enriched air that comes out of the enricher is 3 to 5 degrees Celsius higher than room temperature, which causes the patient to inhale warmer air, so the temperature of the oxygen-enriched air that comes out of the enricher is 3 to 5 degrees Celsius higher than room temperature. If the temperature exceeds 30℃, it will cause discomfort and measures must be taken to lower the temperature of the enriched air.One way to lower the temperature is to lengthen the conduit for the enriched air that exits the enricher and cool it. However, as mentioned above, enriched air has nearly saturated water vapor, so when the temperature drops, water droplets form on the conduit and need to be removed.
It is sufficiently cooled in the enricher main body, and the cooled enriched air is taken out of the oxygen enricher without coming into direct contact with the vacuum pump exhaust passage, and the temperature of the oxygen-enriched air is maintained at the same temperature as the intake air. The present inventors have previously proposed an enrichment device that can be kept at a temperature almost equal to that of air (room temperature), or within 2 degrees Celsius at the highest (Japanese Patent Application No. 1983-
(See Specification No. 155198 (Japanese Patent Publication No. 16724, Showa 61)).

The present inventors conducted further research in order to put this membrane-based oxygen enricher into practical use, and found that the oxygen enricher was compact, lightweight, and had excellent separation performance (oxygen concentration, enriched air volume, durability, etc.). It goes without saying that the material has excellent performance (e.g. performance, etc.), but it has been found that it is even more desirable for the material to have low noise and vibration in actual use. Particularly when this oxygen enricher is used for medical purposes, it is required to have a structure with as little noise and vibration as possible.

The main sources of noise in oxygen enrichers are the air intake fan and the vacuum pump. Therefore, in order to reduce noise, it is necessary to use low-noise fans and vacuum pumps and to take soundproofing measures by using soundproofing materials or sound-absorbing metals.

However, in the case of a vacuum pump, if you try to reduce the noise by surrounding the pump with soundproofing material, etc.
Because the pump cannot be cooled sufficiently, the temperature of the pump and motor parts increases, which accelerates wear and fatigue of the materials in the pump and motor parts, and causes deformation and breakage due to heat, which shortens the life of the vacuum pump. often occurs. For this reason, it is necessary to soundproof the vacuum pump without reducing its lifespan.

In addition, if we are to put oxygen enrichers into practical use, it is necessary to take measures to further reduce the noise of the air intake fan.Furthermore, especially when this enricher is used for medical purposes, Due to the high humidity, there is a risk of bacteria breeding in the enriched air piping, so it was found that measures were needed to prevent bacteria from entering the pipes and breeding.

The present inventors have arrived at the present invention as a result of intensive research aimed at solving these practical problems in developing an oxygen enricher using the membrane method.

That is, the present invention is an oxygen enricher for obtaining oxygen-enriched air from the atmosphere, which comprises: (i) an oxygen-enriching module containing a large array of elements each consisting of a selective oxygen-permeable membrane; (ii) the oxygen-enriched air; (iii) a vacuum pump for reducing pressure inside each element of the oxygen enrichment module and removing oxygen enriched air; and (iv) a vacuum. In a structure consisting primarily of moisture separation means for removing excess moisture in the oxygen-enriched air exiting the pump, (1) for introducing atmospheric air into the module and discharging nitrogen-enriched air; A fan is provided in front of the module's atmospheric air supply port, (2) it has a storage chamber for housing a vacuum pump, and (3) it has a nitrogen enriched air supply port that exits the module's exhaust port. Air is introduced into the storage chamber with a vacuum pump;
The storage chamber cools the vacuum pump with nitrogen-enriched air, and has a dedicated passage so that the nitrogen-enriched air discharged from the forced cooling exhaust port of the vacuum pump is directly discharged to the outside of the storage chamber. (4) The nitrogen-enriched air discharged from the storage chamber is
It has an exhaust passage that allows the oxygen-enriched air to be discharged outside the oxygen enricher without coming into direct contact with the conduit; (6) A conduit is provided for discharging water from the water separation means to the outside of the oxygen enricher, and at least the inner wall of the air exhaust passage is made of a sound-absorbing material; At least a portion of the conduit is filled with a porous body forming a capillary through which water can flow, and the entire cross section of the inside of the conduit is filled with a porous body that has a flow rate of oxygen-enriched air in its dry state.
The flow rate of the oxygen-enriched air after water separation is 10% or less at a pressure difference of 200 mmH ₂ O, and the flow rate of water passing through the membrane in a wet state is 10% or less of the unit area of the selective oxygen permeable membrane at a pressure difference of 200 mmH ₂ O. An oxygen enricher characterized in that the oxygen enricher has an oxygen concentration of at least 5 c.c./hour (1 m ² ).

The features and effects of the structure of the oxygen enricher of the present invention will be explained below.

(a) The noise of the vacuum pump is reduced and the temperature of the vacuum pump is prevented from rising.

The vacuum pump used in the oxygen enricher of the present invention is mainly composed of a pump part for discharging air and reducing pressure, and an electric part for moving the pump, and also removes heat generated by moving the driving part. In order to do this, a forced cooling air generator having at least one cooling air intake and exhaust port is installed inside the vacuum pump.

In the enricher of the present invention, in order to reduce the noise of the vacuum pump, which is a noise source, the vacuum pump is placed in a pump storage chamber, and the inside and/or outside of the storage chamber is provided with soundproofing material or the like.

To cool the vacuum pump, nitrogen-enriched air discharged from the module in the enricher is introduced into the vacuum pump housing chamber and used.

The nitrogen-enriched air cools the outside of the vacuum pump, is taken into the vacuum pump through a forced cooling air inlet of the vacuum pump, cools the vacuum pump, and is discharged through a forced cooling air outlet.

The exhaust air cools the vacuum pump and comes out, so it is warmed by heat exchange. When this exhaust air returns to the vacuum pump storage chamber, the pump storage chamber is heated, and the cooling effect of the vacuum pump eventually decreases. ,
The vacuum pump will overheat and its life will be shortened.

Therefore, in the enrichment device of the present invention, a dedicated passage is provided so that the cooling exhaust air coming out of the vacuum pump does not return to the vacuum pump storage chamber, but is directly discharged to the outside of the storage chamber.

Since the exhaust air does not return to the storage chamber, the vacuum pump will not be further heated by the warmed exhaust air even during long-term operation, and once an equilibrium state is reached, the vacuum pump will not be heated any further. The life of the pump will not be shortened.

In the vacuum pump storage chamber of the present invention, the outside of the vacuum pump is efficiently cooled so that the nitrogen-enriched air discharged from the module introduced into the storage chamber enters the forced cooling air intake inlet of the vacuum pump. It is preferable to disturb the flow of nitrogen-enriched air so as to

For this purpose, for example, a board or a fence that disturbs the flow of wind is installed inside the storage room.

In the present invention, when the dedicated passage is in direct contact with the vacuum pump, the vibration of the vacuum pump is transmitted to the enricher through the dedicated passage, and the vibration of the enricher increases, so the dedicated passage is made of vibration-proof material. Alternatively, it is preferable to use a structure or material that has a vibration-proof structure and does not transmit the vibrations of the vacuum pump.

Furthermore, the enrichment device of the present invention has an air flow and is structured to allow the air to flow out, so that the sound travels through the air flow to the outside. Therefore, it is preferable that at least the inside of the dedicated passage inside the vacuum pump storage chamber and/or the exhaust path provided outside the storage chamber be made of sound-absorbing material, so that the sound leaking outside is absorbed by the sound-absorbing material. .

Furthermore, it is preferable to bend the air exhaust path to lengthen the flow path. In particular, if the air exhaust path passes through the bottom of the enricher, the flow path can be made longer, and by moving the air exhaust path to the rear of the enricher, noise at the surface can be reduced. .

(b) Efforts must be made to reduce the noise of the air intake fan.

In the oxygen enricher of the present invention, since the air intake fan is installed in front of the enrichment module, the air flow from the fan can be particularly long, and the sound absorption effect inside the array of elements reduces noise. It has a measurable structure.

As the fan used in the present invention, a multi-blade fan is preferably used in terms of noise reduction.

A multi-blade fan is one in which a large number of blades are installed on a certain circumference at a certain angle perpendicular to the flow direction, and by rotating these blades, an air flow is generated. and
For example, a cross flow fan, a sirotskov fan, etc. This multi-blade fan generates noise in the high frequency range compared to an axial flow fan, typically a propeller type fan that generates airflow by cutting the air with blades, but the sound in the high frequency range is soundproofed. It is easy to eliminate the noise using materials, etc., and the noise can be reduced after all.

Furthermore, when using a multi-blade fan that has a larger flow rate of air than the flow rate of air passing through the enrichment module, it is possible to In the case of reverse airflow, it is preferable to operate the fan in a state where the pressure resistance is small, since the power of the fan can be lowered and the noise can also be reduced. In this case, even if there is no particular provision of a flow path with lower air resistance than the enrichment module, the airflow outlet of the fan and the air intake of the enrichment module may be slightly shifted from each other, and the intake from the fan's airflow outlet The same effect can be obtained by allowing a portion of the atmosphere to leak out of the enrichment module through the air intake port of the module.

(c) Measures are taken to prevent bacterial growth and contamination.

The oxygen-enriched air that passes through the membrane is a gas that has passed through an ideal filter, and is clean air with no bacteria or dirt mixed in, but the humidity of the enzyme-enriched air is close to saturation. Since the air is high in air, there is a possibility that bacteria, etc. may enter the enriched air conduit from the outside, creating conditions that make it easy for bacteria to propagate.

Examples of routes for contamination of bacteria from the outside include the outlet of enzyme-enriched air and the drainage channel of water. Therefore, a filter such as a bacteria filter is installed at the enriched air outlet to prevent bacteria from entering the enrichment device when the system is stopped.

On the other hand, the water drainage channel is a flow channel for draining water separated by the water separator, and has a porous structure having capillary tubes through which water can flow.

Copper is contained in the porous structure to prevent bacteria from entering through the outlet of the drainage channel. Copper can be in the form of fibers, wires, copper pieces, etc., but copper powder can also be used.

All copper melts in the presence of moisture and generates metal cations, which exhibit a bactericidal effect.

In the oxygen enricher of the present invention, a heat exchanger is used as a means for cooling the enriched air that comes out through the warm pump, and copper is used as the material for the heat exchanger as described above. This is preferable from the viewpoint of effectiveness.

Since the inside of the enricher is warm, there is a risk that insects such as cockroaches may enter through the exhaust vents, etc. Therefore, the exhaust vents, etc., where they may enter, should be surrounded with a net-like material that does not obstruct the exhaust flow. Good too.

(d) Enriched air can be kept at a low temperature The vacuum pump heats up during operation, and when the enriched air passes through it, it comes out warmed, so a cooling means is provided. The cooling means is a heat exchanger that cools with incoming atmospheric air, and when the enriched air exits the heat exchanger, it has the ability to cool to a temperature equal to but close to that of the incoming air. It is something. On the other hand, enriched air has a higher water vapor permeation rate than nitrogen or oxygen, so it is rich in water vapor, and water comes out when it is cooled, so water separation means is provided next. What is more important is that the cooled enriched air is not heated until it is led outside the enricher, and in particular, the structure is such that the vacuum pump is not exposed to the cooled hot air. Thus, the temperature of the oxygen-enriched air is approximately the same as the intake air (room temperature), but can be kept within 2°C at most.

Above, the relationship between the characteristics and effects of the structure of the enricher of the present invention has been explained individually, but these are not independently related, but the entire structure is organically connected, and the present invention as a whole is It produces the characteristics of an enricher.

In order to have a structure that has the above-mentioned functions in order to have the features of the present invention, and to achieve compactness, it is best that the air supply port and the air discharge port in the enrichment module are located on the same plane.

Next, each component of the enricher of the present invention will be explained in detail.

(A) Oxygen enrichment module: The module consists of an array of multiple elements, each of which is provided with a selective oxygen permeable membrane on one or both sides of a support plate.

If the separation element is provided with selective oxygen permeable membranes on both sides of the support plate, the membrane area per element can be maximized, that is, if the membrane area is constant, the number of elements can be minimized. It is suitable for use because the enrichment device is lightweight and compact.

In the case of this double-sided membrane element, it has a common outlet for taking out oxygen-enriched air through the membranes on both sides, and has a structure in which the pressure loss within the element is 100 mmHg or less. This is preferable in terms of module simplification and separation efficiency.

The selective oxygen permeable membrane used in the present invention can be made of any material as long as the ratio of oxygen to nitrogen permeability coefficients is 2.0 or more. From above, preferably 2.5 or more, more preferably 3.0
The above are advantageous.

The material should have a high oxygen permeability coefficient, and the amount of permeation is inversely proportional to the film thickness, so
A membrane layer that is as thin as possible and durable is used. The form of the membrane is a flat membrane that can be placed on a support plate, and any of a thin membrane, an asymmetric membrane, and a composite membrane can be used.

Among various selective oxygen permeable membranes, poly-α-olefin has the highest oxygen permeability coefficient as a membrane material.
10 ^-10 Ω (STP)・cm/cm ²・sec・cmHg or higher, which is higher than other general polymers, and the selectivity is also 3.0
As described above, it is possible to make an ultra-thin film of 0.5 microns or less, and it is durable, so it is suitably used.

Among poly-α-olefins, poly-4-meterpentene-1 and copolymers of it and other polyolefins have an oxygen permeability coefficient of 10 ^-9 cc (STP).
cm/cm・sec・cmHg or more, and the selectivity is also stable and 3.0 or more, so it is suitably used.

Such an ultra-thin film of polyα-olefin can be produced, for example, by the method previously proposed by the present inventors (Japanese Patent Application No.
169461). The thickness of ultrathin membranes is less than 0.5 microns, and such ultrathin membranes are handled on a porous support.

The support plate of the present invention maintains the shape of the element and functions both to maintain the membrane and to serve as a flow path for oxygen-enriched air that has passed through the membrane. The latter function, which serves as a flow path for oxygen-enriched air, has a large impact on the separation efficiency of the membrane, and if the flow path is difficult for gas to pass through, the pressure loss will be large, creating a pressure difference in the element, and increasing the separation efficiency. Even if this is carried out, the actual pressure difference across the membrane is small;
The amount of permeation decreases in proportion to the pressure difference. Furthermore, in the separation of mixed gases, the pressure ratio before and after the membrane (high pressure side/
It is known that the larger the pressure drop (on the low pressure side), the better the actual separation of the gas mixture will be. However, if the pressure drop is large, the pressure on the low pressure side will increase, the pressure ratio will also decrease, and the enrichment obtained by permeating through the membrane will increase. The concentration of the gas decreases.

Therefore, the support plate should have a structure that does not obstruct the flow path of the oxygen-enriched air that has passed through the membrane, that is, a structure that has as little pressure loss as possible. It is as follows.

This pressure loss structure applies to both single-sided membrane elements and double-sided membrane elements, but double-sided membrane elements are particularly important because the amount of oxygen-enriched air that passes through the membrane is large.

To measure the pressure loss in the present invention, the support plate structure is cut into pieces measuring 50 cm in length and 25 cm in width, and the entire surface of the element is covered with a gas barrier film. Seal both ends of the 50cm side to prevent gas from leaking, and attach a thick tube-shaped opening (e.g., a tube with an inner diameter of about 8mm) to both ends of the 25cm side so that gas can flow through it without resistance, and close the other ends. On the other hand, leave the tube opening open so that it can be squeezed, and measure the pressure at both ports when the air volume on the suction side is 1/min to reduce pressure from the opposite tube opening, and take the difference as the pressure loss. . Measurements are carried out at 25°C.

The support plate of the present invention is a metal plate such as an aluminum plate, a duralumin plate, or an iron plate, or a plastic plate such as a polypropylene plate, a hard PVC plate, a FR-PET plate, or an unsaturated polyester plate, or a perforated plate of stainless steel or polypropylene. It is constructed by laminating a net material, a nonwoven fabric, a porous material, etc., or a combination of these materials on both sides of a mesh material. In this case, it is necessary to combine and laminate the elements so that the pressure loss in each element falls within the above range.

When a wire mesh or perforated plate is not used in the center of the support plate, net material facilitates the flow of air within the support plate, and has a gas flow effect, so its selection is particularly important. . The net material preferably has a rough texture, and the material may be either plastic or metal, but plastic is preferred from the viewpoint of weight reduction. If it is made of plastic, it is preferably stiff, and examples of the material include polypropylene, polyethylene terephthalate, and nylon. Examples of commercially available net materials include Du Pont's Vexar and Tokyo Polymer's Netron.

Non-woven fabrics are used to protect the shape of the membrane, as the net-like material is open and uneven, so if pressure is applied, the membrane will deform into the shape of the net-like material and may be damaged. It also has the effect of facilitating the flow of water. Therefore, it is preferable that the nonwoven fabric has a smooth surface and the mesh size is smaller than the mesh size of the net-like material.The material of the nonwoven fabric is polyethylene terephthalate, polypropylene, polyethylene, nylon, etc. As for the
Examples include Teijin's Unicell R type and Nippon Vilin's MR type.

Porous materials maintain separation membranes in the same way as nonwoven fabrics, and nonwoven fabrics can be considered a type of porous material, but they generally have smaller pore diameters than nonwoven fabrics. Depending on the type of separation membrane, the separation membrane may be manufactured integrally with the porous material or in a laminated form. Porous materials include, for example, polypropylene porous membrane (trade name: Celguard, manufactured by Celanese Corporation), cellulose ester porous membrane (trade name: Millipore, manufactured by Millipore Corporation), Teflon porous membrane (trade name: Fluoropore, manufactured by Sumitomo Electric Industries, Ltd.), polycarbonate porous membrane. Examples include a membrane (trade name: Nuclepore, manufactured by Nomura Microscience Co., Ltd.), a regenerated cellulose membrane (trade name: Fuji Micro Filter, manufactured by Fuji Film Corporation), and the like.

Any combination of support plates can be used as long as the pressure loss is within the pressure loss range of the present invention, but it is preferable that the support plates themselves have a durable structure and are resistant to deformation. The structure of the support plate is preferably one in which a net-like material, a nonwoven fabric, and a porous material are symmetrically arranged in this order around a metal plate or the like in the middle, since there is no unevenness in pressure or imbalance in the enriched air flow. As a preferred structure, at least one layer of a net-like material, a nonwoven fabric, and a porous material are provided on both sides of the metal plate in this order.
It is preferable to provide each type of element because the pressure loss is small, the deformation of the membrane is prevented, and the element itself is durable.

The thickness of the support plate is preferably as thin as possible from the viewpoint of compactness, and the thickness is 5 mm or less, preferably 4 mm or less, and more preferably 3 mm or less.

The element used in the present invention is provided with an outlet for taking out the oxygen-enriched air obtained by passing through the permeable membrane.

It is necessary to select an outlet with a cross-sectional area and length that causes almost no pressure loss at that part.

The outer periphery of the element, except for the outlet, is sealed to prevent air leakage. That is, the structure is such that mixing of the supply air and the enriched air that has passed through the membrane does not occur. In order to prevent the membranes from touching the elements created in this way, and to provide a flow path for the air to flow over the membrane surface, a large number of spacers are inserted and assembled together.

The combined array forms a storage boxed enrichment module having an air inlet and a nitrogen enriched air outlet. Note that the oxygen-enriched air that has permeated the membrane from each element is collected in a collecting pipe connected to the outlet of each element, and can be taken out of the module through the pipe. The flow of the supplied air and the taken-out air is preferably countercurrent or crossflow, and countercurrent is most preferred in terms of separation efficiency. In the module of the present invention, the inlet and outlet ports are positioned such that the flow of supply air is countercurrent or cross-flow to the flow of oxygen-enriched air withdrawal.

(B) Fan for feeding atmospheric air; It functions to take in atmospheric air and send the atmospheric air to the oxygen enrichment module, and is provided in front of the atmospheric air supply port as described above. The amount of air to be fed is at least 5 times, preferably at least 10 times, and more preferably at least 30 times the amount of oxygen-enriched air in order to minimize concentration polarization on the membrane surface and increase separation efficiency.

The preferred form of the fan and its preferred method of operation are as described above.

(C) Vacuum pump; It has the function of reducing the pressure inside the element through the enriched air outlet and serving as the driving force for separation, and also takes out enriched air through the outlet and sends out the enriched air as exhaust gas for the pump.

As the pump is used for human inhalation, it is preferable to use one that does not contain fine particles such as oil, and it is preferable that the pump is oil-less, has low noise, and is durable. The pump capacity includes the required amount of enriched air,
It varies greatly depending on the oxygen concentration and the performance of the separation membrane, but for example, for medical purposes, when the oxygen concentration is 35% or more and the enriched air rate is 6/min or more, the separation membrane has an oxygen and nitrogen selectivity of 3.5. , a pump capable of producing a flow rate of 6/min at an absolute pressure of 270 mmHg is required. As a medical enrichment device, a diaphragm-type oilless pump made by Geast or Thomas in the US or Iwaki in Japan is suitably used.

In the present invention, the vacuum pump is installed within the pump storage chamber. The storage room has an intake port for the nitrogen-enriched air coming out of the enrichment module, and the storage room itself and/or the inside of the room are soundproofed by gluing soundproofing materials, sound-absorbing materials, etc. Measures are being taken.

As the soundproofing material, any material that is normally used as a soundproofing material or a sound-absorbing material can be used.

For example, there are reporting materials such as urethane, styrene, or foamable synthetic rubber, and/or rubber materials such as urethane and synthetic rubber. Furthermore, a sound insulating material mainly composed of metal fibers such as lead fibers or metal pieces can also be suitably used.

The dedicated passage for exhaust air used for cooling the vacuum pump of the present invention may have any shape and type as long as the exhaust air does not leak into the pump storage chamber. For example, it is possible to make it into a round wind tunnel shape, with one end attached to the exhaust port and the other end extending outside the pump storage room, or alternatively, the exhaust port of the vacuum pump can be provided with an exhaust introduction section, and the There is also a method of attaching a hood and discharging the exhaust air outside the pump storage room.

However, when operating the vacuum pump, the vibration of the pump is large, so it is necessary that the vibration not be transmitted to the enricher main body through the dedicated passage. For this purpose, the dedicated passage must be made of a material or structure that absorbs vibrations. Therefore, as a dedicated passage, a flexible structure is required, for example, a bellows shape, or a two-way exhaust passage.
There is also a method to prevent the transmission of vibrations by dividing the layers into layers and providing gaps at the boundaries so that they do not touch each other. Even if there are some gaps, the suction effect of the exhaust air flow will prevent the exhaust air from leaking outside, and it may also be preferable since it will disturb the air flow inside the pump chamber.

The inner wall of the exclusive passage inside the storage chamber and/or the exhaust passage provided outside the storage chamber is made of a sound-absorbing material so that noise does not leak outside through the passage.

As such a sound absorbing material, the materials exemplified above can be used.

(D) Cooling and water separation means: A heat exchanger is used as a cooling means to cool the enriched air coming out through the warm pump.
The cooling air supplied to the heat exchanger uses intake air.In order to cool the enriched air to the intake air, it is preferable to place the heat exchanger right next to the intake air intake, and the surrounding area is vacuum It is necessary that it is not easily warmed by the heat of the pump.

The material of the heat exchanger is preferably metal from the viewpoint of heat conduction, and among these, as mentioned above, copper is particularly preferable since it has a sterilizing effect. Although any conventional shape can be used as the shape of the heat exchanger, a shape that is compact and allows water to flow through is preferable, and therefore a coil-shaped one is preferably used. The capacity of the heat exchanger is required to cool the enriched air at the outlet of the heat exchanger to a temperature that is equal to or almost close to that of the cooling air, and its length depends on the amount and temperature of the enriched air. The length of the coil is preferably at least 20 cm in some cases.

The water separation means serves to separate the water in the enriched air from the air. The simplest method is to introduce enriched air containing water from the side of a cylindrical tube and separate the air from the top and the water from the bottom.

In order to improve the separation efficiency, a filler such as a rasp ring can be placed in the cylinder,
Obstacles such as shelves may also be provided. The water that has accumulated below the water separation length must be discharged to the outside, but the means for doing so must be such that the separated water can flow sufficiently outside and that enriched air does not leak significantly through it. Therefore, you need something with as little air leakage as possible.

A porous body having capillary tubes through which water can flow is most suitable as a water discharge part that meets such requirements.
Although any structure can be used for the porous body, one that satisfies the following properties is preferable. Normally, piping such as a tube is used to extract enriched air from a pump, but since a pressure loss occurs when gas flows through the piping system, some pressure is also applied at the water discharge part. Therefore, it is necessary to measure the performance of the water discharge part under pressure, and the size of the measurement is, for example, when this oxygen enricher is used for medical purposes, with an oxygen enriched air volume of 6/min. When the pressure drop is generally
100 to 500 mmH ₂ O, so we measured the performance under a pressure of 200 mmH ₂ O, and to express the performance, first of all, as for the air flow rate, for practical purposes as an oxygen enricher, the enriched air should be as high as possible. Since it is desirable to use the air without leakage, the amount of enriched air in dry conditions is preferably 10% or less, more preferably 5% or less.

On the other hand, as for the amount of water distilled from the water discharge section, since the enricher is usually used in an atmospheric atmosphere, it should be possible to distill at least the amount of water that is separated during operation under high temperature and high humidity conditions in the summer. indispensable,
The amount of water separated varies greatly depending on the amount of water vapor permeated through the separation membrane, but generally the water vapor permeation coefficient is 50 to 100 times the oxygen permeation coefficient, and the oxygen permeation coefficient is 10 ^-9 cc・With a membrane of the order of cm/cm ² sec cmHg, the amount of water separated per unit area of the separation membrane (m ² ) is 5c.c when operating at a temperature of 30°C and humidity of 90% RH with a pressure difference of 1 atm. ./hours~10c.c./
time and the flow rate of water from the water outlet is at least 5 c.c./hour, preferably 10 c.c./hour per unit area (m ² ) of the separation membrane.

Examples of preferred structures of porous bodies that satisfy such performance include those in which a tube of plastic or the like is filled with a porous body such as plastic, a flexible porous body such as a sponge, or a fibrous material. As the fibrous material, either cotton-like or string-like material can be used. Among these filamentous materials, hollow fibers are particularly preferable from the viewpoint of water distillation since they are formed of connected capillary tubes. Air leakage and water flow rate can be adjusted by adjusting the pore size, porosity, and filling degree of the porous material, but it is also possible to adjust the outside of the tube that houses the porous material by tightening or loosening it. It can also be easily done by doing.

It is preferable that such a porous body has little air leakage or fluctuation in water distillation amount even when used for a long time.
As for the material, inorganic materials such as glass and ceramics are preferable to organic materials.

In order to facilitate the flow of water, it is also preferable to subject the surface of the material forming the porous body to hydrophilic treatment.

In the present invention, it is desirable that the porous body contains metallic copper in order to prevent the contamination of bacteria from the water discharge section. As metal copper,
It can be used in any form, such as a thin copper wire, copper piece, or copper powder, but it is necessary that it does not fall off during use.

The content of copper is not particularly limited, but is at least 0.5% by weight of the total porous member. Since there are also porous structures made of copper material, cases of 100% copper are also included in the present invention.

The water thus discharged through the water outlet can be stored in a tray, or it can be evaporated by impregnating it in an evaporating tray and/or a material that absorbs water well, such as gauze. , but is not particularly limited.
Particularly in the latter case, the water can be efficiently evaporated by using the cooling air of the pump, and there is no need for water to flow out of the enricher or the trouble of discarding accumulated water, which is a preferable method.

(E) Others; For example, a column filled with activated carbon can be installed to remove harmful gases such as NOx and SOx from the enriched air, as well as bad odors, or a biofilter can be installed to remove bacteria from the enriched air. . In particular, biofilters are necessary because they prevent bacteria from entering the enriched air conduit during periods of rest. Further, accessory parts such as an alarm device, a time meter, a flow meter, a pressure gauge, etc., may be installed to detect and notify abnormalities during operation.

The oxygen enricher of the present invention is constructed by incorporating the above-mentioned components, but when used as a medical enricher, when the oxygen concentration is required to be 35% or more, the oxygen and nitrogen selectivity is 3.0 to 3.0 as a separation membrane. When using a material in the range of 4.0, the operating pressure should be 230 to 230 absolute pressure.
A reduced pressure of 300mmHg or less is required. At this time, the required amount of oxygen-enriched air must be available at this pressure.

The oxygen enricher of the present invention is particularly characterized by low noise, and is further characterized by preventing the contamination of bacteria and the like.

The enrichment device of the present invention is mainly used for human inhalation for medical purposes, but is not limited to this.
It can also be used to produce air for small combustion furnaces and oxygen-enriched air for industries such as aquaculture.

Next, an example of the structure of the enricher of the present invention will be shown in the drawings, but this is for the purpose of explanation and is not intended to be limiting.

The structural diagram of the element used in the enricher is shown below.
Shown in 1. 11 is an aluminum plate (thickness 1mm, 250mm x
500mm), 12 is polypropylene net (thickness
50μ, 14 mesh), 13 is polyethylene terephthalate nonwoven fabric (thickness 230μ, 180g/m ² in the figure),
14 is a polypropylene porous material (thickness 25μ, maximum pore diameter
0.2 micron), and the enriched air outlet 15
is provided. The periphery of the element is fixed with adhesive over a width of 15mm to prevent air leakage. The pressure loss of this element was 30 mmHg. Stack 15 of these elements to create the enrichment module shown in Figure 2. Rubber spacers with a thickness of 3 mm are placed between each element at both edges of 500 mm to prevent the membranes from touching each other and to form a flow path for atmospheric air. In Figure 2, 21 is a module hook, 22 is an atmospheric air supply port, 23 is a nitrogen-enriched air discharge port, 24 is an array of elements, and 25 is a collecting pipe that brings together the enriched air intake ports. and is connected to a vacuum pump.

The water discharge part has an outer tube with an inner diameter of 6mm and an outer diameter of 10mm.
It is a polyvinyl chloride tube of m/m, and the inside is filled with bundles of glass fibers whose surface has been treated with hydrophilic treatment.

Also, in this bundle, 5 parts by weight of copper wire with a diameter of 0.05 mm was mixed with the glass fiber bundle in the same length as the glass fiber.

The total length of this conduit is 30 cm, and its performance is 200 mm H ₂ O pressure difference in dry condition and air flow rate of 45
cc/min, the water flow rate was 35 c.c./hour at the same pressure difference of 200 mm H ₂ O under humid conditions. Since the membrane area of this enricher is 3 m ² , the water flow rate per unit area is 11
cc/hour.

Since the enriched air amount is 7/min as before, the air flow rate is 0.6%.

Figures 3 and 4 show internal diagrams of the enricher.

21 is an oxygen enrichment module, and 45 is a cross flow fan (made of vinyl chloride vanes, manufactured by Royal Electric Co., Ltd.). By driving this fan 4
The outside air is taken in through a filter 4, which is first cooled by a cooler 41, passes through a fan 45, enters the supply port of the module 22 21, and exits from the discharge port 23. At this time, there is a 4 mm gap between the air outlet of the fan and the air intake for the module (61 in Figure 5) to reduce the resistance of the fan.

The nitrogen-enriched air coming out of the outlet enters the vacuum pump storage chamber 51 and cools the vacuum pump 52. The forced cooling air outlet of the vacuum pump passes through a dedicated passage 53 and 54, passes through an exhaust furnace 55, and is discharged to the outside while evaporating water accumulated in an evaporating dish 56.

The inside of the vacuum pump storage chamber 51 is soundproofed with a urethane foam material that is 5 mm thick and whose surface is covered with lead foil. The dedicated passage is composed of two parts 53 and 54, 53 is a wind tunnel that covers the forced exhaust port of the vacuum pump so that the exhaust air flows toward the upper part of the vacuum pump, and 54 is a wind tunnel with an opening slightly larger than the opening at the top of 53, and is fixed to the ventilation path of 55.

The vibration of the vacuum pump when operating it is 5.
Although it is transmitted to 3, it is not transmitted to 54, and only the exhaust air is sent. The sides 53, 54 and 55 through which the wind passes are made of urethane sound absorbing material for soundproofing.

When attaching the vacuum pump 52 to the enrichment device, it is supported and fixed by a spring 57 to absorb vibrations of the pump. The exhaust air passage is independent and has a structure that does not heat the enriched air that has been cooled through the electrical instruments and cooler placed in the 58 rooms.

On the other hand, the enriched air passes through the collecting pipe 25, enters the vacuum pump, and the enriched air exiting there is cooled through the cooling pipe 41 (made of copper), and then the moisture separator 4.
2, the water is separated from the water, and is discharged outside from the outlet 50 through an activated carbon layer and a bacteria filter without intersecting with the exhaust air path of the pump.

The water separated by the water separator exits from a water discharge section 43 to an evaporating dish 56. 46 is a power switch,
47 is a flow meter, 48 is a pressure gauge, and 49 is a timer.

When this oxygen enricher is operated in a room at 160℃ and 56% RH, the oxygen concentration is 40.3% and the enriched air amount is 7/
It was hot in minutes. The temperature of the enricher coming out was 168°C. In addition, the noise during operation was 40 dB(A) at a distance of 0.7 m, and the temperature in the pump storage room was 37°C when the pump was operated for more than 24 hours.

For comparison, a similar enrichment device was used, except that the dedicated passages 53 and 54 were not provided, and the cooling air from the vacuum pump was diffused into the vacuum pump storage chamber, and a portion of it was exhausted through the exhaust passage 55. After 24 hours of operation in a 16°C room, the temperature inside the pump storage room was 61°C.
℃ showed a tendency to increase first.

[Brief explanation of the drawing]

Figure 1 is an example of a structural diagram of Nirement used in the oxygen enricher of the present invention, Figure 2 is an example of an external view of an enrichment module, Figure 3 and Figure 2 are examples of an external view of an enrichment module.
4 shows an internal view of the enricher.

Claims (1)

[Scope of Claims] 1. An oxygen enricher for obtaining oxygen-enriched air from the atmosphere, comprising: (i) an oxygen-enriching module containing a large array of elements consisting of selective oxygen-permeable membranes; (ii) the oxygen-enriched air; (iii) a vacuum pump for reducing the pressure inside each element of the oxygen enrichment module and extracting oxygen enriched air from the vacuum pump; In a structure consisting primarily of moisture separation means for removing excess moisture in the exiting oxygen-enriched air, A fan is provided in front of the atmospheric air supply port of the module, (2) it has a storage chamber for storing a vacuum pump, and (3) the nitrogen-enriched air leaving the outlet of the module is introduced into the storage chamber having a vacuum pump,
The storage chamber cools the vacuum pump with nitrogen-enriched air, and has a dedicated passage so that the nitrogen-enriched air discharged from the forced cooling exhaust port of the vacuum pump is directly discharged to the outside of the storage chamber. (4) The nitrogen-enriched air discharged from the storage chamber is
It has an exhaust passage that allows the oxygen-enriched air to be discharged outside the oxygen enricher without coming into direct contact with the conduit; (6) A conduit is provided for discharging water from the water separation means to the outside of the oxygen enricher, and at least the inner wall of the air exhaust passage is made of a sound-absorbing material; At least a portion of the conduit is filled with a porous body forming a capillary tube through which water can flow, and the porous body has a porous body that has a flow rate of oxygen-enriched air passing through it in a dry state.
The flow rate of the oxygen-enriched air after water separation is 10% or less at a pressure difference of 200 mmH ₂ O, and the flow rate of water passing through the membrane in a wet state is 10% or less of the unit area of the selective oxygen permeable membrane at a pressure difference of 200 mmH ₂ O. An oxygen enricher characterized in that the oxygen enricher is at least 5 c.c./hour (1 m ² ).