A flat membrane humidification unit and a flat membrane humidifier

Abstract

The present invention discloses a flat membrane humidifying unit and a flat membrane humidifier, which comprise: two flow channel plates and a moisture transfer membrane. On both the front and back sides of the flow channel plates, there are provided a plurality of flow channels recessed into the plate surface and arranged side by side at intervals in the left-right direction, and on the other side corresponding to the flow channels, there are a plurality of ridges protruding out of the plate surface; the two flow channel plates are divided into a wet-side flow channel plate and a dry-side flow channel plate, and the ridges of the wet-side flow channel plate are provided with a plurality of pits connecting two adjacent flow channels. The flat membrane humidifier comprises a plurality of the above-mentioned flat membrane humidifying units and a plurality of the above-mentioned moisture transfer membranes, and the plurality of flat membrane humidifying units and the plurality of moisture transfer membranes are sequentially attached, which can enhance the water vapor transfer effect from the humidifying gas to the gas to be humidified, increase the utilization area of the moisture transfer membrane, improve the uniformity of the wet air inlet flow rate, and is applicable to the field of fuel cells.

Description

Technical Field

[0001] The present invention relates to the field of fuel cell humidification, and particularly to a flat membrane humidification unit and a flat membrane humidifier. Background Art

[0002] With the application of fuel cells, the integration and development of fuel cell systems have put forward higher requirements for humidifiers; traditional flat membrane humidifiers have the advantages of simple structure, easy manufacturing, and stable operation. However, some of their moisture transfer membranes are in contact with the flow channel plates and not in contact with the humidifying gas and the gas to be humidified, so they cannot participate in the humidification work, resulting in a large waste, low membrane utilization area, further problems such as large volume of the humidifier, and uneven distribution of humid air leading to low mass transfer efficiency, and thus unable to meet the requirements of the integration and development of fuel cell systems, and therefore cannot be widely used. Summary of the Invention

[0003] The purpose of the present invention is to provide a flat membrane humidification unit and a flat membrane humidifier to solve one or more technical problems existing in the prior art, and at least provide a beneficial choice or create conditions.

[0004] The technical solution adopted to solve the above technical problems:

[0005] First, the present invention provides a flat membrane humidification unit, which includes: two flow channel plates, and a moisture transfer membrane located between the two flow channel plates. Both the front and back sides of the flow channel plates are provided with a plurality of flow channel grooves that are recessed into the plate surface and arranged side by side at left and right intervals, and on the other side corresponding to the flow channel grooves are a plurality of ridges that protrude out of the plate surface; the two flow channel plates are divided into a wet side flow channel plate and a dry side flow channel plate. The ridges of the wet side flow channel plate are provided with a plurality of pits that connect adjacent two flow channel grooves; among the opposite sides of the wet side flow channel plate and the dry side flow channel plate, the flow channel grooves correspond to each other one by one, and the ridges correspond to each other one by one.

[0006] The beneficial effect of the flat membrane humidification unit provided by the present invention is: when in use, a wet flow domain is formed between the plurality of flow channel grooves on one surface of the wet side flow channel plate and the moisture transfer membrane. The wet flow domain includes a plurality of wet side flow channels, and a dry flow domain is formed between the plurality of flow channel grooves on one surface of the dry side flow channel plate and the moisture transfer membrane. The dry flow domain includes a plurality of dry side flow channels. A plurality of pits on the ridges located between adjacent two flow channel grooves in the wet side flow channel plate connect the adjacent two wet side flow channels. When the wet gas passes through the wet side flow channels, water is transferred to the dry gas in the dry flow domain through the moisture transfer membrane. At the same time, the wet gas can flow along the pits to the adjacent wet side flow channels. The existence of the pits can increase the flow rate of the humid air flowing towards the moisture transfer membrane, so that more water is transferred through the membrane; at the same time, it also connects the originally independent wet side flow channels into a whole, making the wet gas distributed to both sides, achieving the effect of strengthening heat and mass transfer.

[0007] As a further improvement of the above technical solution, a plurality of ventilation holes corresponding to the pits one by one are provided on the ridges of the dry-side flow channel plate.

[0008] The ventilation holes coincide with the pits in position, which can increase the area of heat and mass transfer. Combined with the increased moisture transfer area on the wet side, it ensures that water vapor can smoothly pass through the moisture transfer membrane from the wet flow region and flow from the moisture transfer membrane to the dry flow region, increasing the utilization area of the membrane.

[0009] As a further improvement of the above technical solution, the pits on the ridges of two adjacent front and back sides in the wet-side flow channel plate are arranged staggeredly.

[0010] During use, generally moisture transfer membranes are attached to both sides of the wet-side flow channel plate, and wet flow regions are formed on both sides of the wet-side flow channel plate. The pits on the wet flow regions on both sides are arranged staggeredly, so that the increased regions through which the wet gas flows on both sides are staggered, that is, the contact points of the wet-side flow channel plate with the moisture transfer membranes on both sides are distributed staggeredly, improving the installation stability of the wet-side flow channel plate.

[0011] In addition, a protrusion protruding out of the plate surface is formed at the position of the flow channel groove of the wet-side flow channel plate corresponding to the pit. In this way, the protrusions on two adjacent flow channel grooves are also staggered. The protrusions can cause the wet gas to generate vortices in the wet-side flow channel. The eddy current will cause the water to stay for a longer time. Therefore, the existence of the protrusions will make the time of mass transfer and heat transfer longer. Since the generated vortices reduce the wake region and make the boundary layer thinner, resulting in flow instability and better fluid mixing, the heat and mass transfer effect is further enhanced. That is to say, the wet gas flowing through the wet-side flow channel will be blocked by the protrusion in front of the pit, so that a part of the wet gas flows through the pit and enters another wet-side flow channel; the protrusion is formed based on the pit, which makes production more convenient and also reduces the material used for the wet-side flow channel plate.

[0012] As a further improvement of the above technical solution, the left and right regions of the wet-side flow channel plate are divided into a left flow channel plate region and a right flow channel plate region. The pits on the left flow channel plate region and the right flow channel plate region are both arranged obliquely left and right along the flow direction of the flow channel groove and are symmetrically arranged left and right.

[0013] The existence of the pits and protrusions not only connects the wet flow regions and increases the moisture transfer area of the moisture transfer membrane, but also has the function of guiding the flow to the left and right sides because they are obliquely left and right along the wet air flow direction, which can make the wet gas more evenly distributed, avoid the problem of large flow in the middle and small flow on both sides in the traditional form, make the moisture transfer membrane be utilized evenly and reasonably, and improve the mass transfer efficiency.

[0014] As a further improvement of the above technical solution, the wet-side flow channel plate is provided with a middle flow channel plate region located between the left flow channel plate region and the right flow channel plate region. The pits on the middle flow channel plate region are arranged to extend left and right.

[0015] The pits and protrusions on the middle flow channel plate area mainly divert the wet gas in the middle wet flow domain to the left and right, and another part of the wet gas flows through the wet side flow channels on the middle flow channel plate area.

[0016] As a further improvement of the above technical solution, there are no pits on the back of the flow channel grooves on the left and right ends of the wet side flow channel plate.

[0017] There are no pits in the flow channel grooves on the left and right outermost sides of the wet side flow channel plate, and no protrusions are formed inside the flow channel grooves, which can reduce the sealing difficulty and improve the sealing reliability.

[0018] As a further improvement of the above technical solution, wet side sealing edges are provided on both left and right edges of the wet side flow channel plate.

[0019] The wet side sealing edges are mainly used to seal the wet flow domain.

[0020] As a further improvement of the above technical solution, dry side sealing edges opposite to the wet side sealing edges are provided on both left and right edges of the dry side flow channel plate.

[0021] The dry side sealing edge is fitted opposite to the wet side sealing edge or with the moisture transfer membrane, and can fit the wet flow domain and the dry flow domain.

[0022] In addition, the present invention also provides a flat membrane humidifier, which includes a plurality of the above flat membrane humidifying units, and also includes a plurality of the above moisture transfer membranes, and the plurality of flat membrane humidifying units and the plurality of moisture transfer membranes are sequentially fitted and arranged.

[0023] The beneficial effects of the present invention are: this flat membrane humidifier can enhance the water vapor transfer effect from the humidifying gas to the gas to be humidified, increase the utilization area of the moisture transfer membrane, and improve the uniformity of the wet air inlet flow rate. Compared with the conventional parallel flow flat membrane humidifier, its theoretical membrane utilization area can be increased from 50% to 75%; compared with the conventional cross flow flat membrane humidifier, its theoretical membrane utilization area can be increased from 25% to 75%. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The following further describes the present invention in conjunction with the drawings and embodiments;

[0025] Figure 1 is an exploded view of one embodiment of the flat membrane humidifying unit provided by the present invention;

[0026] Figure 2 is a top view of one embodiment of the wet side flow channel plate provided by the present invention;

[0027] Figure 3 is a front view of one embodiment of the wet side flow channel plate provided by the present invention;

[0028] Figure 4 The front view of one embodiment of the dry side flow channel plate provided by the present invention;

[0029] Figure 5 The front view of one embodiment of the flat membrane humidifier provided by the present invention. Detailed implementation manners

[0030] This part will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the drawings. The function of the drawings is to supplement the description in the text part of the specification, enabling people to intuitively and vividly understand each technical feature and the overall technical solution of the present invention. However, it should not be construed as a limitation on the protection scope of the present invention.

[0031] In the description of the present invention, it should be understood that for the orientation description, such as the upper, lower, front, rear, left, right, etc., the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the present invention.

[0032] In the description of the present invention, if there are descriptions with words such as "several", its meaning is one or more, and the meaning of multiple is more than two. Understandings such as greater than, less than, exceeding, etc. do not include the present number, and understandings such as above, below, within, etc. include the present number.

[0033] In the description of the present invention, unless otherwise clearly defined, words such as setting, installation, connection, etc. should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0034] Refer to Figures 1 to 5 , the following embodiments are made for the flat membrane humidifier of the present invention:

[0035] The flat membrane humidifier of this embodiment includes a plurality of flat membrane humidification units and a plurality of moisture transfer membranes 300, wherein the plurality of flat membrane humidification units and the plurality of moisture transfer membranes 300 are sequentially attached.

[0036] Such as Figure 1As shown, the flat membrane humidification unit of this embodiment includes a wet-side flow channel plate 100, a dry-side flow channel plate 200, and a moisture transfer membrane 300 located between the wet-side flow channel plate 100 and the dry-side flow channel plate 200. That is to say, the dry-side flow channel plate 200, the moisture transfer membrane 300, and the wet-side flow channel plate 100 of the flat membrane humidifier of this embodiment are arranged at intervals. Among them, the dry-side flow channel plate 200 and the wet-side flow channel plate 100 are generally similar in structure. First, the general structure of the dry-side flow channel plate 200 and the wet-side flow channel plate 100 is described in terms of the flow channel plate. Specifically: The flow channel plate is divided into front and back sides. A plurality of flow channels and a plurality of ridges are provided on both the front and back sides of the flow channel plate. The plurality of flow channels are arranged at intervals left and right. The flow channels are recessed into the plate surface, and the ridges are formed on the other surface corresponding to the flow channels. Both the flow channels and the ridges extend back and forth. That is to say, the flow channel plate can be formed by stamping or bending.

[0037] As Figure 2 and Figure 3 As shown, it is set that the flow channels and ridges on the wet-side flow channel plate 100 are respectively wet-side flow channels 110 and wet-side ridges 120. That is to say, the wet-side flow channel plate 100 includes a plurality of upper wet flow channel plates 130, a plurality of side wet flow channel plates 140, and a plurality of lower wet flow channel plates 150. The upper wet flow channel plates 130, the side wet flow channel plates 140, and the lower wet flow channel plates 150 are connected in sequence to form a plurality of wet-side flow channels 110 and a plurality of wet-side ridges 120. And a plurality of pits 160 arranged at intervals front and back are provided on the wet-side ridges 120. Both ends of the pits 160 are respectively communicated with two adjacent wet-side flow channels 110. The pits 160 are formed on the outer surfaces of the upper wet flow channel plates 130 and the lower wet flow channel plates 150.

[0038] The wet-side flow channels 110 on the wet-side flow channel plate 100 and the moisture transfer membrane 300 form a plurality of wet-side flow channels. The pits 160 connect two adjacent wet-side flow channels. When the wet gas passes through the wet-side flow channels, water is transferred to the dry gas in the dry flow domain through the moisture transfer membrane 300. At the same time, the wet gas can flow along the pits 160 to the adjacent wet-side flow channels. The existence of the pits 160 connects the originally independent wet-side flow channels to form an overall wet flow domain, enabling the wet gas to be distributed to both sides.

[0039] As Figure 1 and 4 As shown, it is set that the flow channels and ridges on the dry-side flow channel plate 200 are respectively dry-side flow channels 210 and dry-side ridges 220. That is to say, the dry-side flow channel plate 200 includes a plurality of upper dry flow channel plates 230, a plurality of side dry flow channel plates 240, and a plurality of lower dry flow channel plates 250. The upper dry flow channel plates 230, the side dry flow channel plates 240, and the lower dry flow channel plates 250 are connected in sequence to form a plurality of dry-side flow channels 210 and a plurality of dry-side ridges 220. A dry flow domain is formed between the dry-side flow channels 210 on the dry-side flow channel plate 200 and the moisture transfer membrane 300. The dry flow domain includes a plurality of dry-side flow channels.

[0040] In this embodiment, the dry-side flow channel grooves 210 and the wet-side flow channel grooves 110 are in one-to-one correspondence, and the dry-side ridges 220 and the wet-side ridges 120 are in one-to-one correspondence. In other embodiments, the dry-side flow channel grooves 210 and the wet-side flow channel grooves 110 are cross-shaped, and the dry-side ridges 220 and the wet-side ridges 120 are cross-shaped.

[0041] Among them, in this embodiment, a plurality of ventilation holes 260 are provided on the dry-side ridges 220. The plurality of ventilation holes 260 are arranged at intervals front and back. That is to say, the ventilation holes 260 are formed on the upper dry flow channel plate 230 and the lower dry flow channel plate 250, and the ventilation holes 260 and the pits 160 are in one-to-one correspondence and overlap.

[0042] The ventilation holes 260 and the pits 160 in this embodiment overlap and correspond in position, which can increase the area of heat and mass transfer. Combined with the increased moisture transfer area on the wet side, it ensures that water vapor can smoothly pass through the moisture transfer membrane 300 from the wet flow domain and flow from the moisture transfer membrane 300 to the dry flow domain, increasing the membrane utilization area.

[0043] Furthermore, protrusions 170 are formed at positions corresponding to the pits 160 on the wet-side flow channel grooves 110 and the dorsal wet-side ridges 120 of this embodiment. The protrusions 170 protrude out of the plate surface, that is, the protrusions 170 are formed on the inner surfaces of the upper wet flow channel plate 130 and the lower wet flow channel plate 150. The pits 160 on two adjacent wet-side ridges 120 in this embodiment are arranged staggeredly. In this way, the protrusions 170 on two adjacent wet-side flow channel grooves 110 also stagger each other. The protrusions 170 can cause the wet gas to generate vortices in the wet-side flow channel. The eddy current will cause the residence time of water to be longer. Therefore, the presence of the protrusions 170 will make the time of mass transfer and heat transfer longer. Since the generated vortices reduce the wake region and make the boundary layer thinner, resulting in flow instability and better fluid mixing, the effect of heat and mass transfer is enhanced. That is to say, the wet gas flowing through the wet-side flow channel will be blocked by the protrusions 170 in front of the pits 160, so that a part of the wet gas flows through the pits 160 and enters another wet-side flow channel; the protrusions 170 are formed based on the pits 160, which makes production more convenient and also reduces the material used for the wet-side flow channel plate 100.

[0044] Although the presence of the pits 160 causes an increase in the velocity in the gap region between the pits 160 and the moisture transfer membrane 300, the flow velocity of the wet air in the regions behind and in front of the pits 160 decreases, which increases the total residence time of the wet air; in addition, the eddy current generated due to the pits 160 will cause the residence time of water to be longer. Therefore, the presence of the pits 160 will make the time of mass transfer and heat transfer longer; in summary, the protrusions 170 and the pits 160 can play the role of strengthening heat and mass transfer.

[0045] Moreover, the wet-side flow channel plate 100 is divided into a left flow channel plate area and a right flow channel plate area. The left and right flow channel plate areas are the left and right regions of the wet-side flow channel plate 100. The pits 160 on the left and right flow channel plate areas are inclined along the left-right direction towards the internal fluid flow direction of the wet-side flow channel 110, and the pits 160 on the left and right flow channel plate areas are left-right symmetric. The existence of the pits 160 and the protrusions 170 not only connects the wet flow domain and increases the moisture transfer area of the moisture transfer membrane 300, but also has the function of guiding the flow to the left and right because they are inclined left and right along the wet air flow direction, which can make the wet gas more evenly distributed, avoid the problem of large flow in the middle and small flow on both sides in the traditional form, and make the moisture transfer membrane 300 be utilized evenly and reasonably to improve the mass transfer efficiency.

[0046] Furthermore, the wet-side flow channel plate 100 is also divided into a middle flow channel plate area located between the left flow channel plate area and the right flow channel plate area. Among them, the pits 160 and the protrusions 170 on the middle flow channel plate area extend left and right. The pits 160 and the protrusions 170 on the middle flow channel plate area mainly divert the wet gas in the wet flow domain in the middle to the left and right, and another part of the wet gas flows through the wet-side flow channel on the middle flow channel plate area.

[0047] In this embodiment, there are no pits 160 on the back of the wet-side flow channel 110 at the left and right ends of the wet-side flow channel plate 100. There are no pits 160 on the wet-side flow channels 110 at the leftmost and rightmost sides of the wet-side flow channel plate 100, and no protrusions 170 are formed inside the wet-side flow channels 110. This can reduce the sealing difficulty and improve the sealing reliability.

[0048] Moreover, wet-side sealing edges 180 are connected to the left and right edges of the wet-side flow channel plate 100, and dry-side sealing edges 270 are connected to the left and right edges of the dry-side flow channel plate 200. The dry-side sealing edges 270 are relatively attached to the wet-side sealing edges 180 or attached to the moisture transfer membrane 300, and can attach the wet flow domain and the dry flow domain.

[0049] The moisture transfer membrane 300 in this embodiment is a polymer water permeable membrane or a high-density fiber membrane.

[0050] The present invention takes the parallel flow flat membrane humidifier as an example, but is not limited to its application on the parallel flow flat membrane humidifier. For the cross flow flat membrane humidifier, it has a more obvious improvement. Compared with the conventional parallel flow flat membrane humidifier, its theoretical membrane utilization area can be increased from 50% to 75%; compared with the conventional cross flow flat membrane humidifier, its theoretical membrane utilization area can be increased from 25% to 75%.

[0051] The flat membrane humidifier of the present invention can achieve enhanced mass transfer, increased membrane utilization area, and uniform distribution of the wet-side inlet flow. There are no constraints on the specific shape, inclination angle, arrangement method, flow channel size, etc. of the protrusions 170, which depend on the requirements of the fuel cell system.

[0052] The preferred embodiments of the present invention have been specifically described above. However, the present invention is not limited to the described embodiments. Those skilled in the art can make various equivalent variations or substitutions without departing from the spirit of the present invention, and these equivalent variations or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A flat membrane humidification unit, Characterized in that: It includes: two flow channel plates, and a moisture transfer membrane (300) located between the two flow channel plates. The front and back sides of the flow channel plates are provided with a plurality of flow channel grooves that are recessed into the plate surface and arranged side by side at left and right intervals, and on the other side corresponding to the flow channel grooves are a plurality of ridges that protrude out of the plate surface; The two flow channel plates are divided into a wet side flow channel plate (100) and a dry side flow channel plate (200). The ridges of the wet side flow channel plate (100) are provided with a plurality of pits (160) that connect adjacent two flow channel grooves; The ridges on the dry side flow channel plate (200) are provided with a plurality of air holes (260) that correspond one by one to the pits (160); The pits (160) on the ridges of the front and back sides of adjacent two of the wet side flow channel plate (100) are arranged staggeredly; At the position corresponding to the flow channel groove and the pit (160) on the wet side flow channel plate (100), there is a protrusion (170) that protrudes out of the plate surface; The left and right two regions of the wet side flow channel plate (100) are divided into a left flow channel plate region and a right flow channel plate region. The pits (160) on the left flow channel plate region and the right flow channel plate region are both arranged obliquely from left to right along the flow direction of the flow channel groove and are arranged symmetrically from left to right; The wet side flow channel plate (100) is provided with a middle flow channel plate region located between the left flow channel plate region and the right flow channel plate region. The pits (160) on the middle flow channel plate region are arranged to extend from left to right.

2. A flat membrane humidification unit according to claim 1, Characterized in that: The back surfaces of the flow channel grooves at the left and right ends of the wet side flow channel plate (100) are not provided with pits (160).

3. A flat membrane humidification unit according to claim 2, Characterized in that: Wet side sealing edges (180) are arranged on both left and right edges of the wet side flow channel plate (100).

4. A flat membrane humidification unit according to claim 3, Characterized in that: Dry side sealing edges (270) are arranged on both left and right edges of the dry side flow channel plate (200).

5. A flat membrane humidifier, Characterized in that: It includes a plurality of flat membrane humidification units according to any one of claims 1 to 4, and also includes a plurality of the above-mentioned moisture transfer membranes (300). The plurality of flat membrane humidification units and the plurality of moisture transfer membranes (300) are sequentially laminated and arranged.

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