JP2002066262A - Hollow fiber membrane type humidifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow fiber membrane type humidifier whose humidifying capability can be prevented from decreasing by additional installation of an extremely simple structure. SOLUTION: This hollow fiber membrane type humidifier is provided with a hollow fiber membrane module (3) comprising a cylindrical housing (2) having a plurality of gas flowing-in holes (2A) arranged in the circumferential direction in one end part and a plurality of gas flowing-out holes (2B) arranged in the circumferential direction in the other end part and a hollow fiber membrane assembly (FA) of a bundle of a large number of water-permeable hollow fiber membranes (HF) housed in the housing (2). A flowing-in hole communication groove for communicating the respective gas flowing-in holes (2A) one another in the circumferential direction is formed in the inner circumferential face in one end part of the cylindrical housing (2) and a flowing-out hole communication groove for communicating the respective gas flowing-out holes (2B) one another in the circumferential direction is formed in the inner circumferential face in the other end part of the cylindrical housing (2).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hollow fiber membrane humidifier having a lightweight and compact structure suitable for a fuel cell system, and more particularly to a hollow fiber membrane humidifier capable of preventing a decrease in humidification capacity. is there.

[0002]

2. Description of the Related Art In recent years, various electric vehicles equipped with a traveling motor instead of a conventional engine have been developed. As one of such electric vehicles, for example, PEMFC (Pr
The development of a fuel cell vehicle equipped with a hydrogen ion exchange membrane fuel cell (hereinafter, referred to as a PEM fuel cell), which is abbreviated as oton Exchange Membrane Fuel Cell, as a power source for a traveling motor is rapidly progressing.

[0003] The PEM fuel cell is configured as a stack having a structure in which a number of cells as power generation units are stacked. Each cell includes an anode-side separator having a hydrogen supply path and a cathode-side separator having an oxygen supply path. It has a structure in which a membrane-electrode assembly, which is abbreviated as MEA (Membrane Electrode Assembly), is interposed therebetween. This ME
A denotes an anode-side electrode catalyst layer and a gas diffusion layer sequentially laminated on one surface of a solid polymer material hydrogen ion exchange membrane abbreviated as PEM (Proton Exchange Membrane).
On the other side of the EM (hydrogen ion exchange membrane), a cathode-side electrode catalyst layer and a gas diffusion layer are sequentially laminated.

In this type of PEM fuel cell, hydrogen gas flows through the hydrogen supply passage from the anode inlet side to the anode outlet side, and humidified air containing oxygen flows through the oxygen supply passage from the cathode inlet side. When flowing toward the cathode outlet, hydrogen ions permeate the PEM (hydrogen ion exchange membrane) of the wet MEA from the anode side of each cell and move to the cathode side, so that each cell has an electromotive force of about 1V. Occurs. Therefore, in a PEM fuel cell having such a power generation mechanism, in order to continuously supply humidified air and hydrogen gas to continue power generation, the cathode inlet side is pumped by, for example, a supercharger. An air supply system for humidifying and supplying air is provided, and an air discharge system for discharging wet off-gas is provided on the cathode outlet side. Further, a hydrogen gas supply system for supplying hydrogen gas by an ejector is provided on the anode inlet side. And, between the air supply system and the air discharge system, in order to humidify the air fed to the cathode inlet side,
Hollow fiber membrane humidifier with a lightweight and compact configuration
-71795).

FIG. 8 shows another conventional example of this type of hollow fiber membrane humidifier. The hollow fiber membrane humidifier shown in FIG.
A plurality of water permeable holes H1 are arranged at one end along the circumferential direction, and a plurality of gas permeable holes H2 are arranged at the other end along the circumferential direction. A hollow fiber membrane module FM including a hollow fiber membrane assembly FA in which hollow fiber membranes HF are bundled is provided. The hollow fiber membrane module FM has one end connected to and supported by a head block HB1 having a sweep gas inflow passage P1 and an off gas outflow passage P2, and a head block HB2 having a sweep gas outflow passage P3 and an off gas inflow passage P4. And the other end is connected and supported.

In the conventional hollow fiber membrane type humidifier shown in FIG. 8, the off-gas inflow passage P4 of the head block HB2 is used.
Is supplied with a wet off gas having a high water content discharged to the air discharge system of the fuel cell system, and is supplied to the sweep gas inflow passage P1 of the head block HB1 by the supercharger. Low dry air is supplied as a sweep gas. As a result, in the hollow fiber membrane humidifier, the off-gas is
4 and flows through the inside of each hollow fiber membrane HF constituting the hollow fiber membrane assembly FA of the hollow fiber membrane module FM to the off-gas outflow passage P2. At the same time, the sweep gas flows from the sweep gas inflow passage P1 to the gas inflow hole H1 provided at one end of the cylindrical housing CH of the hollow fiber membrane module FM.
The gas further flows into the cylindrical housing CH, passes through the gap in the hollow fiber membrane assembly FA, and flows from the gas outlet H2 provided at the other end of the cylindrical housing CH to the sweep gas outlet passage P3. And in this hollow fiber membrane type humidifier, each hollow fiber membrane HF constituting the hollow fiber membrane assembly FA
The water exchange is performed between the off gas passing through the inside of the filter and the sweep gas passing in contact with the outer periphery of each hollow fiber membrane HF, and the off gas having a high moisture content is dehumidified,
A sweep gas having a low moisture content is humidified.

[0007]

In the above-described hollow fiber membrane module FM of the conventional hollow fiber membrane humidifier, the gas inlet holes H1 at one end of the cylindrical housing CH are provided.
The gas outlet holes H2 at the other end are arranged along the circumferential direction of the cylindrical housing CH, but are spaced apart from each other. Therefore, the sweep gas flowing into each gas inlet H1 at one end of the cylindrical housing CH cannot be smoothly diffused along the circumferential direction of the inner peripheral surface of the cylindrical housing CH, and the hollow fiber membranes There is a tendency that the gap in the aggregate FA flows in a streak form from each gas inlet H1 on one end side to each gas outlet H2 on the other end side. In this case, in each hollow fiber membrane HF constituting the hollow fiber membrane assembly FA, a portion that hardly contributes to moisture exchange occurs due to a small amount of the swept gas passing therethrough, and the humidifying ability of the hollow fiber membrane module FM decreases. I do.

Therefore, an object of the present invention is to provide a hollow fiber membrane humidifier which can prevent a decrease in humidification capacity by adding a very simple structure.

[0009]

As means for solving the above problems, a hollow fiber membrane humidifier according to the present invention comprises a plurality of gas inlet holes provided at one end and a plurality of gas inlet holes provided at the other end. A hollow fiber membrane module comprising a large number of water-permeable hollow fiber membranes bundled and housed in a cylindrical housing in which the gas outflow holes are arranged along the circumferential direction. A hollow fiber membrane that exchanges moisture between a gas passing therethrough and a gas coming into contact with the outer periphery of each hollow fiber membrane by passing through the inside of a cylindrical housing from the gas inlet to the gas outlet. In the humidifier, an inflow hole communication groove that connects the gas inflow holes to each other is provided on an inner peripheral surface of one end of the cylindrical housing.

In the hollow fiber membrane type humidifier according to the present invention, one gas having a different moisture content passes through the inside of each hollow fiber membrane, and the other gas flows into one end of the cylindrical housing at each gas inlet. By passing through the gap between each hollow fiber membrane in the cylindrical housing from the hole toward each gas outlet hole at the other end, moisture exchange is performed through each hollow fiber membrane contacting both gases,
The gas having a high moisture content is dehumidified, and the gas having a low moisture content is humidified. At this time, the inflow hole communication groove provided on the inner peripheral surface of one end of the cylindrical housing allows the other gas flowing into each of the gas inflow holes at one end of the cylindrical housing to pass through the inner peripheral surface of the cylindrical housing. Spread smoothly along the circumferential direction.
For this reason, the other gas substantially uniformly spreads the gap between the hollow fiber membranes in the cylindrical housing from the entire circumferential direction within one end of the cylindrical housing toward the gas outlet holes at the other end of the cylindrical housing. pass. That is, the other gas substantially uniformly passes through the gaps between the hollow fiber membranes without drifting in the circumferential direction of the cylindrical housing and comes into contact with more hollow fiber membranes.

In the hollow fiber membrane type humidifier according to the present invention, an outflow hole communication groove for communicating the gas outflow holes arranged at the other end of the cylindrical housing with each other is provided on the inner periphery of the other end of the cylindrical housing. When provided on the surface, the outflow hole communication groove allows the other gas passing through the gap between the hollow fiber membranes toward the other end of the cylindrical housing to flow in the circumferential direction inside the other end of the cylindrical housing. Along the way to each gas outlet. Therefore, the other gas passes through the gaps between the hollow fiber membranes more uniformly from the entire circumferential area in one end of the cylindrical housing to the entire circumferential area in the other end. That is, the other gas passes through the gaps between the respective hollow fiber membranes more uniformly without drifting in the circumferential direction of the cylindrical housing, and comes into contact with more hollow fiber membranes.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a hollow fiber membrane humidifier according to the present invention will be described with reference to the drawings. In the drawings to be referred to, FIG. 1 is a perspective view showing a structure of a hollow fiber membrane humidifier according to one embodiment, FIG. 2 is a sectional view showing a structure of a hollow fiber membrane humidifier according to one embodiment, and FIG. FIG. 4 is a sectional perspective view showing the inner peripheral surface of one end of the cylindrical housing shown in FIG.
FIG. 3 is a sectional perspective view showing the inner peripheral surface of the other end of the cylindrical housing shown in FIG. 2.

As shown in FIGS. 1 and 2, a hollow fiber membrane humidifier 1 according to one embodiment has a plurality of gas inlet holes 2A arranged at one end in a circumferential direction and a plurality of gas inlets 2A at the other end. Hollow fiber membrane module 3 in which a hollow fiber membrane assembly FA in which a large number of water-permeable hollow fiber membranes HF are bundled is accommodated in a cylindrical housing 2 in which gas outlet holes 2B are arranged along the circumferential direction. Are provided. And each hollow fiber membrane module 3
Are the sweep gas inflow passage 4 and the off gas outflow passage 5
The other end is connected to and supported by a head block 6 having a sweep gas outflow passage 7 and an off gas inflow passage 8.

The cylindrical housing 2 has a diameter of, for example, 6 mm.
It is made of an engineering plastic material injection-molded into a pipe having a length of about 0 mm, a wall pressure of 4 mm and a length of about 600 mm. Each of the gas inlet holes 2A formed at one end of the cylindrical housing 2 has a diameter of, for example, about 18 mm, and eight gas inlet holes 2A are arranged at equal intervals in the circumferential direction of the cylindrical housing 2. Similarly, each of the gas outlet holes 2B formed at the other end of the cylindrical housing 2 has, for example, a diameter of about 18 mm, and eight gas outlet holes 2B are arranged at equal intervals in the circumferential direction of the cylindrical housing 2.

The hollow fiber membrane assembly FA is formed by bundling about 5000 hollow fiber membranes HF into one. At both ends of the hollow fiber membrane assembly FA, gaps between the hollow fiber membranes HF are sealed with an adhesive while maintaining the openings of the hollow fiber membranes HF, and both ends of the cylindrical housing 2 are sealed. A potting part to be adhered to the part is configured. Then, both ends of the cylindrical housing 2 are hermetically closed by the potting portion.

Each hollow fiber membrane HF constituting the hollow fiber membrane assembly FA is a thin hollow fiber having an inner diameter of about 300 to 700 micrometers. The hollow fiber membrane assembly FA has a function of condensing water vapor in a gas passing through the inside thereof and moving the condensed water to the outside by capillary action.

The head block 6 includes an outer plate 6
A has a structure in which an intermediate plate 6B and an inner plate 6C are sequentially stacked on each other and fastened to each other by bolts and nuts,
Outer plate 6A, intermediate plate 6B, inner plate 6
The sweep gas inflow passage 4 and the off-gas outflow passage 5 are formed across C. Similarly, the head block 9 has a structure in which an intermediate plate 9B and an inner plate 9C are sequentially stacked on an outer plate 9A and fastened to each other with bolts and nuts, and straddles the outer plate 9A, the intermediate plate 9B, and the inner plate 9C. Thus, the sweep gas outflow passage 7 and the off gas inflow passage 8 are formed. The outer plate 6A of the head block 6 and the outer plate 9A of the head block 9 are fastened to each other via long fastening bolts 10, thereby sandwiching each hollow fiber membrane module 3.

Here, in the hollow fiber membrane type humidifier 1 according to one embodiment, the inner peripheral surface at one end of the cylindrical housing 2 constituting the hollow fiber membrane module 3, as shown in FIG. An inflow hole communication groove 2C is provided to allow the gas inflow holes 2A to communicate with each other. Similarly, on the inner peripheral surface at the other end of the cylindrical housing 2, as shown in FIG. 4, an outflow hole communication groove 2 </ b> D for communicating the gas outflow holes 2 </ b> B with each other is provided.

Each of the gas inlet holes 2C is provided with a corresponding one of the gas inlet holes 2C.
A square groove having a width smaller than the diameter of A is formed intermittently along the arrangement center line of the gas inflow holes 2A along the circumferential direction of the cylindrical housing 2. Similarly, the outflow hole communication groove 2D is a square groove having a width smaller than the diameter of each gas outflow hole 2B, and extends along the arrangement center line of each gas inflow hole 2A along the circumferential direction of the cylindrical housing 2. A plurality are formed intermittently. Each of the inflow hole communication grooves 2C and the outflow hole communication grooves 2D is usually
Is integrally formed at the time of injection molding, but may be formed later by machining.

The hollow fiber membrane type humidifier 1 of one embodiment configured as described above includes, for example, a wet off-gas with a high water content discharged into an air discharge system of a fuel cell system (not shown), In order to humidify the air pumped through the air supply system, by performing moisture exchange between the air supply system of the battery system and dry air having a low moisture content that is pumped by a supercharger or the like. Used for

In the hollow fiber membrane type humidifier 1 of one embodiment, the off gas discharged to the air discharge system of the fuel cell system is supplied to the off gas inflow passage 8 of the head block 9, and the swept gas flows into the head block 6. Air in the air supply system of the fuel cell system is supplied to the passage 4 as a sweep gas. In this state, the wet off-gas having a high water content passes through the inside of each hollow fiber membrane HF constituting the hollow fiber membrane assembly FA of each hollow fiber membrane module 3 from the off-gas inflow passage 8 and passes through the head block 6. It flows out to the off-gas outflow passage 5. On the other hand, the dry sweep gas having a low moisture content flows into the cylindrical housing 2 from the sweep gas inflow passage 4 through the respective gas inflow holes 2A provided at one end side of the cylindrical housing 2 of each hollow fiber membrane module 3. Then, the gas flows through the gap in the hollow fiber membrane assembly FA and flows out from the gas outflow holes 2B provided at the other end of the cylindrical housing 2 to the sweep gas outflow passage 7 of the head block 9.

In the hollow fiber membrane humidifier 1 according to this embodiment, the off-gas passing through the inside of each hollow fiber membrane HF constituting the hollow fiber membrane assembly FA and the outer periphery of each hollow fiber membrane HF Is exchanged with the sweep gas passing through the gap in the hollow fiber membrane assembly FA in contact with the gas, the offgas having a high moisture content is dehumidified, and the sweep gas having a low moisture content is humidified. You. Then, the humidified sweep gas having a high moisture content is returned from the sweep gas outflow passage 7 into the air supply system of the fuel cell system.

At this time, as shown in FIG. 3, each of the inflow hole communication grooves 2C provided on the inner peripheral surface of one end of the cylindrical housing 2 is fitted to each of the gas inflow holes 2C at one end of the cylindrical housing 2.
The sweep gas flowing into A is diffused smoothly along the circumferential direction of the inner peripheral surface of the cylindrical housing 2. For this reason, the sweep gas flows through the gap in the hollow fiber membrane assembly FA from substantially the entire circumferential direction within one end of the cylindrical housing 2 toward each of the gas outlet holes 2B at the other end of the cylindrical housing 2. pass.

Each of the communication holes 2D formed on the inner peripheral surface of the other end of the cylindrical housing 2 is formed substantially uniformly from the entire circumferential direction within one end of the cylindrical housing 2. The sweep gas passing through the gap in the hollow fiber membrane assembly FA is received toward the other end of the cylindrical housing 2 and is guided to the gas outlet holes 2B along the circumferential direction in the other end of the cylindrical housing 2 smoothly. .

Therefore, the hollow fiber membrane humidifier 1 of one embodiment
In the above, the sweep gas flowing into the cylindrical housing 2 of each hollow fiber membrane module 3 from each of the gas inflow holes 2A is changed from the entire circumferential direction in one end of the cylindrical housing 2 to the entire circumferential direction in the other end. And uniformly pass through the gap in the hollow fiber membrane assembly FA. That is, the sweep gas is
Since it uniformly passes through the gap in the hollow fiber membrane assembly FA without drifting in the circumferential direction of the cylindrical housing 2 and comes into contact with more hollow fiber membranes HF than before, it is possible to effectively reduce the humidification capacity. Can be prevented.

In the hollow fiber membrane type humidifier of the present invention, an inflow hole communication groove for the gas inflow hole 2A provided at one end of the cylindrical housing 2 and an outflow hole communication groove for the gas outflow hole 2B provided at the other end. Is not limited to a square shape like the inflow hole communication groove 2C and the outflow hole communication groove 2D of one embodiment,
The shape may be an arc, a V, or an inverted trapezoid.

The inflow hole communication groove for the gas inflow hole 2A can have various shapes, for example, as shown in FIGS. An inflow hole communication groove 2E shown in FIG. 5 includes an annular groove portion 2E1 which is located on the side of the arrangement of the gas inflow holes 2A and extends in the circumferential direction of the inner peripheral surface of the cylindrical housing 2, and a side from the annular groove portion 2E1. Each gas inflow hole 2A
And a communication groove 2E2 that communicates with the communication groove. Also,
The inflow hole communication groove 2F shown in FIG. 6 surrounds each of the gas inflow holes 2A and extends in the circumferential direction of the inner peripheral surface of the cylindrical housing 2, and both side walls are formed into a rounded corrugated shape. ing. Further, the inflow hole communication groove 2G shown in FIG. 7 has a plurality of connection groove portions 2 similar to the inflow hole communication groove 2C in one embodiment.
G1 and a plurality of guide grooves 2G2 projecting laterally from each gas inflow hole 2A. Note that the outflow hole communication groove for the gas outflow hole 2B can also be formed in various shapes as shown in FIGS.

[0028]

As described above, in the hollow fiber membrane humidifier according to the present invention, one gas having a different moisture content passes through the inside of each hollow fiber membrane, and the other gas flows into the hollow fiber membrane. By passing through the gaps between the hollow fiber membranes in the cylindrical housing from the respective gas inflow holes at one end of the housing to the respective gas outflow holes at the other end, moisture is passed through the hollow fiber membranes contacting both gases. The exchange is performed, the gas having a high moisture content is dehumidified, and the gas having a low moisture content is humidified. At this time, the inflow hole communication groove provided on the inner peripheral surface of one end of the cylindrical housing allows the other gas flowing into each of the gas inflow holes at one end of the cylindrical housing to pass through the inner peripheral surface of the cylindrical housing. Spread smoothly along the circumferential direction. For this reason, the other gas substantially uniformly spreads the gap between the hollow fiber membranes in the cylindrical housing from the entire circumferential direction within one end of the cylindrical housing toward the gas outlet holes at the other end of the cylindrical housing. pass. That is, the other gas substantially uniformly passes through the gaps between the hollow fiber membranes without drifting in the circumferential direction of the cylindrical housing and comes into contact with more hollow fiber membranes. Therefore, according to the hollow fiber membrane humidifier of the present invention, it is possible to prevent a decrease in humidification capacity by adding a very simple structure of providing the inflow hole communication groove.

Further, in the hollow fiber membrane humidifier of the present invention, an outflow hole communication groove for communicating each gas outflow hole arranged at the other end of the cylindrical housing with each other is provided at the other end of the cylindrical housing. When provided on the inner peripheral surface, the outflow hole communication groove allows the other gas passing through the gap between the hollow fiber membranes toward the other end of the cylindrical housing to flow around the other end of the cylindrical housing. It leads to each gas outlet smoothly along the direction. For this reason, the other gas passes through the gaps between the hollow fiber membranes more uniformly from the entire circumferential area in one end of the cylindrical housing to the entire circumferential area in the other end. That is, the other gas passes through the gaps between the respective hollow fiber membranes more uniformly without drifting in the circumferential direction of the cylindrical housing, and comes into contact with more hollow fiber membranes. Therefore, a decrease in the humidification ability can be more effectively prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a structure of a hollow fiber membrane humidifier according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a structure of a hollow fiber membrane humidifier according to one embodiment.

FIG. 3 is a sectional perspective view showing an inner peripheral surface of one end of the cylindrical housing shown in FIG. 2;

FIG. 4 is a sectional perspective view showing the inner peripheral surface of the other end of the cylindrical housing shown in FIG. 2;

FIG. 5 is a partially developed view of an inner peripheral surface of one end of a cylindrical housing showing a modification of the inflow hole communication groove for the gas inflow hole shown in FIG. 2;

FIG. 6 is a partially developed view of an inner peripheral surface at one end of a cylindrical housing showing another modification of the inflow hole communication groove for the gas inflow hole shown in FIG. 2;

FIG. 7 is a partially developed view of an inner peripheral surface at one end of a cylindrical housing showing still another modified example of the inflow hole communication groove for the gas inflow hole shown in FIG. 2;

FIG. 8 is a sectional view showing the structure of a conventional hollow fiber membrane humidifier.

[Explanation of symbols]

 1: hollow fiber membrane humidifier 2: cylindrical housing 2A: gas inflow hole 2B: gas outflow hole 2C: inflow hole communication groove 2D: outflow hole communication groove 3: hollow fiber membrane module 4: sweep gas inflow passage 5: off gas Outflow passage 6: Head block 7: Sweep gas outflow passage 8: Off gas inflow passage 9: Head block HF: Hollow fiber membrane FA: Hollow fiber membrane assembly

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Shimanuki 1-4-1, Chuo, Wako, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Mikihiro Suzuki 1-4-1, Chuo, Wako, Saitama F-term in Honda R & D Co., Ltd. (reference) 3D035 AA00 3L055 AA10 BA10 DA05 4D006 GA12 HA02 JB04 MA01 MB03 PB17 PB19 PB65 PC72 PC80 5H026 AA06 5H027 AA06

Claims (2)

[Claims] 1. A large number of water permeable holes are provided in a cylindrical housing in which a plurality of gas inlet holes provided at one end and a plurality of gas outlet holes provided at the other end are arranged along a circumferential direction. A hollow fiber membrane module containing a plurality of hollow fiber membranes bundled and accommodated therein, and a gas passing through each hollow fiber membrane and passing through the cylindrical housing from the gas inlet to the gas outlet. A hollow fiber membrane humidifier that exchanges moisture with a gas that comes into contact with the outer periphery of each of the hollow fiber membranes, wherein the gas flows into the inner peripheral surface at one end of the cylindrical housing. A hollow fiber membrane humidifier having an inflow hole communication groove for communicating holes with each other. 2. The hollow fiber membrane humidifier according to claim 1, wherein an inner peripheral surface of the other end of the cylindrical housing has
The hollow fiber membrane humidifier is provided with an outflow hole communication groove for connecting the gas outflow holes to each other.