JP2000051639A - Membrane type gas drier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a membrane type gas drier which can support a hollow fiber membrane module easily in a casing body and absorb the expansion/ contracti on of the module easily. SOLUTION: In a membrane type gas drier which makes air mixed with water vapor and dehumidified purging air flow through hollow fiber membranes 14 comprising water vapor permeable membranes and discharges the dehumidified air obtained by separating the water vapor in the air mixed with water vapor selectively to the dehumidified purging air side, a hollow fiber membrane module 12 in which the membranes 14 are packed in a cylinder 16 so that each of the opening ends of the membranes 14 faces the end surface of the cylinder 16 and a casing body 10 into which the module 12 is inserted so that the air mixed with water vapor is supplied from one end surface and the dehumidified air is discharged from the other end surface are provided as constituents, and the other end part of the module 12 in which one of the end parts is fixed to the casing body 10 or a side surface close to it is supported by a support part 36 extended from the casing body 10 so that the expansion/ contraction in the long shaft direction of the module 12 is allowed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a membrane gas dryer,
More specifically, a steam mixture gas and a dehumidifying purge gas are flowed through a hollow fiber membrane composed of a steam permeable membrane, and the dehumidified gas obtained by selectively separating water vapor in the steam mixed gas to the dehumidifying purge gas side is obtained. The present invention relates to a film type gas dryer for discharging.

[0002]

2. Description of the Related Art As a dryer that removes water vapor from a steam mixture gas and discharges a dehumidified gas, there is a membrane gas dryer that uses a water vapor permeable membrane that selectively removes water vapor from the steam mixture gas. Such a membrane gas dryer flows a steam mixture gas inside a hollow fiber membrane formed of a water vapor permeable membrane, and flows a dehumidifying purge gas outside the hollow fiber membrane,
Dehumidification is performed by moving steam from the steam mixed gas side to the dehumidifying purge gas side due to the difference in steam partial pressure between the two gases. As a membrane gas dryer using such a hollow fiber membrane, for example, Japanese Unexamined Utility Model Publication No. 3-83617 discloses a membrane gas dryer shown in FIG. In such a film-type gas dryer, the upper portion 102 of the casing body 100
In addition, a supply port 104 for supplying a water vapor mixed gas, a discharge port 106 for discharging dehumidified dehumidified gas, and a discharge port 108 for dehumidified purge gas are provided. A hollow fiber membrane module M in which a large number of hollow fiber membranes 110 made of a water vapor permeable membrane are filled in a tubular body 112 is suspended from the casing body 100 with one end thereof fixed.
An orifice 11 is provided below the hollow fiber membrane module M.
4 is provided, and a part of the dehumidifying gas is taken into the hollow fiber membrane module M as a dehumidifying purge gas.

[0003] In the membrane gas dryer shown in FIG. 4, the steam mixed gas supplied from the supply port 104 to one end face of the hollow fiber membrane module M is supplied from one end of the hollow fiber membrane 110 to the other end. While flowing inside, the water vapor selectively moves to the dehumidification purge gas side flowing outside the hollow fiber membrane 110 to be dehumidified. The dehumidified dehumidified gas is discharged from the other end surface of the hollow fiber membrane module M to the bottom side of the casing body 112. Most of the dehumidified gas discharged to the bottom side of the casing body 112 is
The orifice 1 is discharged from a discharge port 106 formed in the hollow fiber membrane module M and a part thereof is formed in a lower portion of the hollow fiber membrane module M.
From 14 is taken into the hollow fiber membrane module M. The dehumidified gas taken into the hollow fiber membrane module M becomes a dehumidified purge gas flowing outside the hollow fiber membrane 110, and is discharged from a dehumidified purge gas outlet 108 formed in the upper portion 102 of the casing body 100. The dehumidified purge gas discharged from the discharge port 108 contains water vapor moved from the water vapor mixture gas flowing inside the hollow fiber membrane 110.

[0004]

The hollow fiber membrane module M constituting the membrane type gas dryer shown in FIG.
A large number of hollow fiber membranes 110, each of which is fixed with a resin and converged, are filled in a cylindrical body 112, and one end thereof is formed in a casing body 100.
It is fixed and hanging. Therefore, the other end of the hollow fiber membrane module M is a free end, and can easily absorb expansion and contraction of the hollow fiber membrane module M due to a change in the temperature of the steam mixed gas due to a change in the ambient temperature. However, an orifice 114 or the like is also provided at the other end of the hollow fiber membrane module M. When such a hollow fiber membrane module M is cantilevered at one end, the one end of the hollow fiber membrane module M and the casing body It is necessary to improve the strength with 100 and firmly fix it. For this reason, there is a concern that the thickness of the material forming the hollow fiber membrane module M and the casing main body 100 is increased and the weight of the membrane gas dryer is increased.

On the other hand, in the membrane gas dryer shown in FIG. 4, both ends of the hollow fiber membrane module M are connected to the casing body 1.
00, the hollow fiber membrane module M can be easily supported, and the weight of the membrane gas dryer caused by increasing the thickness of the material forming the hollow fiber membrane module M and the casing body 100 Concerns such as increase can be prevented. However, when both ends of the hollow fiber membrane module M are fixed to the casing main body 100, the hollow fiber membrane module M and the casing are expanded and contracted due to a temperature change of the water vapor mixed gas accompanying a change in the ambient temperature. There is a possibility that the seal with the main body 100 may be incomplete and the dehumidification performance may be reduced, or the hollow fiber membrane module M may be damaged. Further, the processing accuracy of the hollow fiber membrane module M and the casing body 100 may also be a problem. Therefore, an object of the present invention is to provide a membrane gas dryer that can easily support a hollow fiber membrane module in a casing body and can easily absorb expansion and contraction of the hollow fiber membrane module.

[0006]

In order to solve the above problems, the present inventors fixed and supported one end of a hollow fiber membrane module to a casing body, and allowed expansion and contraction of the hollow fiber membrane module. As a result, it was considered that it is effective to support the other end of the hollow fiber membrane module. That is, the present invention provides a dehumidification method obtained by flowing a steam mixture gas and a dehumidifying purge gas through a hollow fiber membrane composed of a steam permeable membrane, and selectively separating water vapor in the steam mixture gas to a dehumidifying purge gas side. In a membrane gas dryer that discharges a gas, a hollow fiber membrane module in which a plurality of hollow fiber membranes are filled in the cylinder so that each open end of the hollow fiber membrane faces an end surface of the cylinder, From the casing body into which the hollow fiber membrane module is inserted, so that a steam mixture gas is supplied from one end face of the hollow fiber membrane module and dehumidified gas is discharged from the other end face of the hollow fiber membrane module. The other end of the hollow fiber membrane module having one end fixed to the casing main body or a side surface near the other end is allowed to expand and contract in the longitudinal direction of the hollow fiber membrane module. As it is, in film type gas dryer which is characterized in that it is supported by the support portion extending from the casing body.

In the present invention, by providing a stopper for regulating the axial position of the hollow fiber membrane module in the casing body, adverse effects due to excessive extension of the hollow fiber membrane module, for example, purge air containing water vapor is discharged. Can be prevented from closing the discharge hole of the hollow fiber membrane module. Further, the hollow fiber membrane module is inserted into the casing main body so that the flow direction of the steam mixed gas is reversed and then supplied to the hollow fiber membrane module, or the inner wall surface of the casing main body is hollow. By providing a flow path through which the water vapor mixture gas flows between the outer wall surface of the fiber membrane module and water droplet separation means for separating water droplets contained in the water vapor mixture gas in the flow path, water droplets are removed from the hollow fiber membrane module. Can be prevented. Also, a film-type gas dryer for supplying a part of the dehumidifying gas as a dehumidifying purge gas, comprising a supply port for a water vapor mixture gas, a discharge port for the dehumidifying gas, and an adjusting means for adjusting a supply amount of the dehumidifying purge gas. By providing each of them at one end of the casing body, the dew point of the dehumidified gas discharged from the discharge port can be easily adjusted.

In the present invention, the other end of the hollow fiber membrane module whose one end is fixed to and supported by the casing main body or a side surface near the other end extends from the casing main body so as to allow the hollow fiber membrane module to expand and contract. It is supported by a bearing. As described above, by supporting the hollow fiber membrane module at both ends, the thickness of the material forming the hollow fiber membrane module and the casing main body is increased as compared with the case of supporting the hollow fiber membrane module at one end. Does not require In addition, the other end of the hollow fiber membrane module or a side surface in the vicinity thereof is supported by a support extending from the casing body so as to allow the hollow fiber module to expand and contract. The expansion and contraction of the hollow fiber membrane module due to the change in temperature of the mixed gas can be easily absorbed, and damage to the hollow fiber membrane module itself caused by expansion and contraction of the hollow fiber membrane module can be prevented.

[0009]

FIG. 1 shows an example of a film-type gas dryer according to the present invention. The membrane-type gas dryer shown in FIG. 1 is a vertical membrane-type air dryer, and one end of a hollow fiber membrane module 12 is fixed to a casing body 10. The hollow fiber membrane module 12 has a resin 2 at each end.
Many hollow fiber membranes 14 fixed and converged at 4, 24
Are formed by filling the inside of the cylindrical body 16.
The hollow fiber membrane 14 is filled so that each of its open ends faces the end face of the cylindrical body 16. At the center of the hollow fiber membrane module 12, a pipe 18 into which dehumidified purge air is introduced from the upper end opening is provided. The pipe 18 has a plug member 26 inserted into a lower end opening thereof, and a supply hole 20 for supplying dehumidified purge air to the outside of the hollow fiber membrane 14 filled so as to surround the side surface of the pipe 18. The pipe 18 is opened on the side surface near the upper end. A discharge hole 22 is formed in the side surface near the lower end of the cylindrical body 16 for discharging dehumidified purge air supplied from the supply hole 20 outside the hollow fiber membrane 14 and discharging purge air containing water vapor. I have.

In the casing body 10 to which one end of the hollow fiber membrane module 12 is fixed, a supply port 30 for mixed water vapor, a discharge port 32 for dehumidified air,
A flow control valve 34 is provided as an adjusting means for adjusting the supply amount of the dehumidifying purge air. This flow control valve 3
4 is a dehumidified purge air supply port 48 having one end opened to the discharge chamber 33 from which the dehumidified air is discharged from the hollow fiber membrane module 12 and the other end inserted into the upper end opening of the pipe 18.
, The tip is inserted. For this reason, the supply amount of the dehumidifying purge air can be adjusted by the insertion amount of the distal end portion of the flow control valve 34 into the dehumidifying purge air supply port 48. The adjustment of the supply amount of the dehumidifying purge air can be performed by rotating a protruding portion protruding from the surface of the upper portion 28 of the casing body 10. One end of the discharge port 32 is opened on the inner wall surface of the discharge chamber 33. As shown in FIG. 2, the hollow fiber membrane module 12 has a support portion 36 extending from the inner wall surface on the lower side of the casing body 10.
Is formed with a through-hole 40 into which the lower end portion is inserted. The O-rings 38, 38 (FIG. 1) are inserted into the grooves 42, 42 formed on the upper inner wall surface and the lower inner wall surface of the through hole 40, and the hollow fiber membrane module inserted into the through hole 40. The space between the lower end and the side surface near the lower end is sealed. Furthermore, the groove 44 formed on the inner wall surface of the middle part of the through hole 40 is
The purge air discharged from the discharge hole 22 of the cylindrical body 16 forms a discharge passage for purge air discharged from the purge air discharge hole 46 opened on the lower side surface of the casing body 10.

The hollow fiber membrane module 12 having the vicinity of the lower end inserted into the through hole 40 of the support portion 36 has the side surface near the lower end partially slidingly contacting the inner wall surface of the through hole 40. O-ring 3 inserted in the concave grooves 42, 42
8, 38 are contacted. For this reason, the hollow fiber membrane module 1
The vicinity of the lower end of 2 is supported without its side surface being fixed to the support portion 36. Therefore, when the hollow fiber membrane module 12 whose one end is fixed to the casing body 10 expands and contracts, the hollow fiber membrane module 12 can expand and contract while the side surface near the lower end is supported by the support portion 36,
Breakage of the hollow fiber membrane module 12 can be prevented. Even if the hollow fiber membrane module 12 expands and contracts, if the discharge hole 22 formed in the cylindrical body 16 is within the width of the groove portion 44 formed on the inner wall surface of the middle part of the through hole 40, the discharge hole 22 becomes It is not blocked by the inner wall surface or the like. However, the hollow fiber membrane module 12 expands and contracts excessively, and the discharge hole 2
If 2 deviates from the width of the groove portion 44, the discharge hole 22 may be closed by the inner wall surface of the through hole 40 or the like.

In this respect, the membrane air dryer shown in FIG.
A plate-like stopper 50 is formed radially at the bottom of the casing body 10 below the lower end surface of the hollow fiber membrane module 12, and the discharge hole 22 is closed due to the hollow fiber membrane module 12 extending excessively, etc. Can be prevented. Furthermore,
When the supply of the steam mixed air to the supply port 30 is stopped and the pressure of the hollow fiber membrane module 12 in the direction of the discharge chamber 33 is reduced, the hollow fiber membrane module 12 is moved downward by the pressure of the dehumidified air applied to the discharge chamber 33. May be extruded. Even in such a case, the axial position of the hollow fiber membrane module 12 can be regulated to a predetermined position by the stopper 50. In the membrane air dryer shown in FIG. 1, a flow path 52 through which steam-mixed air passes is formed between the inner wall surface of the casing body 10 and the outer wall surface of the hollow fiber membrane module 12, and the casing body A drain extraction hole 54 for extracting drain is provided on the bottom surface of the base 10. A drain tank for storing drain may be connected to the drain extraction hole 54. A drain drain valve is attached to the drain outlet hole 54, and the valve is manually opened and closed to drain the drain accumulated at the bottom of the casing body 10. Is also good.

In the supply port 30 of the membrane type air dryer,
When compressed air (steam-mixed air) cooled by an aftercooler is supplied from the air compressor, the steam-mixed air flows down the flow path 52 and is inverted at the lower portion of the casing body 10 to be below the hollow fiber membrane module 12. It is supplied into the hollow fiber membrane 14 from the end face. In this way, by reversing the flow direction of the steam-mixed air, it is possible to separate water droplets that are generated by being cooled by the after cooler and may be contained in the steam-mixed air. When such water droplets are supplied into the hollow fiber membrane 14 along with the steam-mixed air, the water vapor permeability of the hollow fiber membrane 14 may decrease. The steam-mixed air supplied into the hollow fiber membrane 14 from the lower end face of the hollow fiber membrane module 12 flows toward the upper end face of the hollow fiber membrane module 12 and flows outside the hollow fiber membrane 14 in the flow direction of the steam mixed air. The water vapor is selectively moved to the dehumidifying purge air flowing in the countercurrent direction to dehumidify the air. The dehumidified dehumidified air is
It is discharged into the discharge chamber 33 from the upper end surface of the hollow fiber membrane module 12.

A part of the dehumidified air discharged into the discharge chamber 33 is supplied to the pipe 18 from the dehumidified purge air supply port 48 with the supply amount being adjusted by the flow control valve 34.
The dehumidified purge air supplied into the pipe 18 is supplied to the pipe 1
8 is supplied to the outside of the hollow fiber membrane 14 from a supply hole 20 formed at the upper end. The dehumidified purge air is supplied to the hollow fiber membrane 1
4 moves toward the lower end side of the hollow fiber membrane 14 and becomes purge air containing steam in the steam-mixed air flowing in the hollow fiber membrane 14. The purge air is discharged from the discharge hole 22 of the cylindrical body 16 to the outside of the system through a purge air discharge hole 46 formed in the casing body 16. On the other hand, most of the dehumidified air discharged to the discharge chamber 33 is discharged from the discharge port 32 and supplied to various users. Here, when the dew point of the dehumidified air is not at the predetermined temperature, for example, when the dew point of the dehumidified air is higher than the predetermined temperature, the dew point of the dehumidified air is adjusted by adjusting the flow control valve 34 in a direction to increase the amount of dehumidified purge air. When the temperature is lower than the predetermined temperature, the flow control valve 34 is adjusted in a direction to reduce the amount of dehumidified purge air.

In the membrane air dryer shown in FIG.
The temperature of the steam-mixed air cooled from the air compressor by the aftercooler changes under the influence of seasonal fluctuations and the like. The hollow fiber membrane module 12 to which the steam-mixed air is supplied expands and contracts with the temperature change of the steam-mixed air. The expansion and contraction of the hollow fiber membrane module 12 can be absorbed by the lower end of the hollow fiber membrane module 12 whose side surface is supported by the support portion 36. For this reason, an excessive force does not act on the hollow fiber membrane module 12 itself or on the sealing member sealing the hollow fiber membrane module 12, and the dehumidifying performance due to the sealing failure due to breakage of the sealing member or the like is eliminated. It is possible to prevent the drop and the situation where the hollow fiber membrane module 12 is damaged.

In the membrane air dryer described with reference to FIGS. 1 and 2, steam-mixed air flowing down a flow path 52 formed between the inner wall surface of the casing body 10 and the outer wall surface of the hollow fiber membrane module 12 is supplied to the casing. The water droplets contained in the steam-mixed air are separated by being inverted at the lower part of the main body 10 and supplied into the hollow-fiber membrane 14 from the lower end surface of the hollow-fiber membrane module 12, but are contained in the steam-mixed air. In order to further separate the water droplets, it is preferable to provide a water droplet separating means for separating the water droplets contained in the steam mixed gas in the flow path 52 as shown in FIG. By providing the spiral blade 55 on the outer periphery of the cylindrical body 16 of the hollow fiber membrane module 12 as such a water droplet separation means, the water vapor mixture gas flowing down the flow path 52 can be swirled to separate water droplets. Further, by storing a demister 56 made of a porous or knitted structure formed of a metal fiber such as a stainless steel fiber, an inorganic fiber, or a sintered body of an inorganic powder in the lower portion of the flow path 52, the spiral blade 55 Fine water droplets that could not be separated can also be separated. In addition, by installing the demister 56 below the flow path 52, an effect of preventing the drain accumulated in the lower part of the casing main body 10 from being wound up can be obtained. In FIG. 3, the spiral blade 55 and the demister 56 are installed in series in the flow path 52, but may be one of the spiral blade 55 and the demister 56.

In FIGS. 1 to 3 described above, the vertical type membrane air dryer has been described.
A horizontal membrane air dryer may be used. As the dehumidifying gas, the film-type gas dryer according to the present invention can be used for dehumidifying not only air but also other gases such as nitrogen gas and oxygen gas. However, when the membrane gas dryer according to the present invention is used for dehumidifying a gas other than air such as nitrogen gas or oxygen gas, the purge gas discharged from the purge gas discharge hole 46 from the viewpoint of safety and economy. Is preferably recovered and reused.

[0018]

In the membrane gas dryer according to the present invention, the other end of the hollow fiber membrane module whose one end is fixed to the casing main body and supported on the other end or a side surface near the other end allows the expansion and contraction of the hollow fiber membrane module. So that it is supported by a bearing extending from the casing body. For this reason, the membrane-type gas dryer according to the present invention needs to increase the thickness of the material forming the hollow fiber membrane module and the casing main body as compared with the case where the hollow fiber membrane module is cantilevered. Therefore, the weight can be reduced. Moreover, the expansion and contraction of the hollow fiber membrane module due to the change in the temperature of the water vapor mixture gas accompanying the change in the ambient temperature can be easily absorbed, and the hollow fiber membrane module itself is damaged due to the expansion and contraction of the hollow fiber membrane module and the internal seal is not damaged. Completeness and the like can be prevented, and the reliability of the film-type gas dryer can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a film-type gas dryer according to the present invention.

FIG. 2 is a partial longitudinal sectional view showing a structure of a support portion using the hollow fiber membrane module of the membrane type gas dryer shown in FIG.

FIG. 3 is a longitudinal sectional view showing another example of the film-type gas dryer according to the present invention.

FIG. 4 is a longitudinal sectional view showing a conventional membrane gas dryer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Casing main body 12 Hollow fiber membrane module 14 Hollow fiber membrane 16 Cylindrical body 30 Supply port 32 Discharge port 34 Flow control valve 36 Bearing 50 Stopper 52 Flow path 55 Spiral blade 56 Demister

Continued on front page F-term (reference) 4D006 GA41 HA01 JA18A JA22A JA25B JB04 KE01Q KE13P KE22Q MA01 MB04 PB65 PC72 4D052 AA01 AA02 EA02 FA01 FA03 GA01 GB01 GB03 GB08

Claims (5)

[Claims] 1. A dehumidifying gas obtained by flowing a steam mixed gas and a dehumidifying purge gas through a hollow fiber membrane comprising a steam permeable membrane and selectively separating water vapor in the steam mixed gas to a dehumidifying purge gas side. In the membrane-type gas dryer that discharges, the opening end of the hollow fiber membrane faces the end face of the cylindrical body,
A hollow fiber membrane module in which the hollow body is filled with a plurality of hollow fiber membranes; a steam mixed gas is supplied from one end face of the hollow fiber membrane module, and a dehumidified gas is discharged from the other end face of the hollow fiber membrane module. The hollow fiber membrane module comprises a casing body into which the hollow fiber membrane module is inserted, and the other end of the hollow fiber membrane module having one end fixed to the casing body or a side surface near the other end thereof, A membrane-type gas dryer characterized in that the hollow fiber membrane module is supported by a support extending from the casing body so that expansion and contraction in the longitudinal direction of the hollow fiber membrane module is permitted. 2. The membrane gas dryer according to claim 1, wherein a stopper for regulating the axial position of the hollow fiber membrane module is provided on the casing body. 3. The hollow fiber membrane module is inserted into the casing body so that the flow direction of the steam mixed gas is reversed before being supplied to the hollow fiber membrane module. The described membrane gas dryer. 4. A film-type gas dryer for supplying a part of a dehumidified gas as a dehumidified purge gas, wherein a supply port of a steam mixture gas, a discharge port of the dehumidified gas, and a supply amount of the dehumidified purge gas are adjusted. The membrane gas dryer according to any one of claims 1 to 3, wherein each of the adjusting means is provided on one end side of the casing main body. 5. A flow path through which a water vapor mixed gas flows is provided between the inner wall surface of the casing main body and the outer wall surface of the hollow fiber membrane module, and water droplets separating water droplets contained in the water vapor mixed gas in the flow path. Claim 1 wherein separation means is provided.
5. The film-type gas dryer according to any one of 4.