WO2022160746A1

WO2022160746A1 - Plate-type self-humidifying and -cooling device, humidifying and cooling unit and humidifying and cooling method

Info

Publication number: WO2022160746A1
Application number: PCT/CN2021/119949
Authority: WO
Inventors: 丁传委; 邢少锋
Original assignee: 上海羿沣氢能科技有限公司
Priority date: 2021-01-27
Filing date: 2021-09-23
Publication date: 2022-08-04
Also published as: CN215527771U; CN113745581A

Abstract

The present invention relates to a plate-type self-humidifying and -cooling device, a humidifying and cooling unit and a humidifying and cooling method. The plate-type self-humidifying and -cooling device comprises a front pressing plate, front-end heat conducting plates, gas-barrier water permeable membranes, rear-end heat conducting plates and a rear pressing plate, wherein one set of the front-end heat conducting plates, the water permeable membranes and the rear-end heat conducting plates form one "humidifying and cooling unit"; and a plurality of humidifying and cooling units are sequentially stacked to form a structure with the dual effect of self-humidifying and -cooling, and are connected and fastened by means of a plurality of sets of bolts to form the plate-type self-humidifying and -cooling device. Cooling water and exhaust-emission wet air of a fuel cell system itself are used for cooling and humidifying high-temperature dry air that enters an electric pile. Therefore, the dual effect of self-humidifying and -cooling by a fuel cell is achieved; and by means of integrated design, the complexity of the system is greatly reduced, system components are reduced, space is saved on, and the power density of the fuel cell system is improved. The present invention has a very high practical value and reference significance.

Description

A plate-type self-humidifying cooling device, a humidifying and cooling unit, and a humidifying and cooling method

technical field

The invention relates to the technical field of fuel cells, in particular to a plate-type self-humidifying and cooling device, a humidifying and cooling unit and a humidifying and cooling method.

Background technique

As an environmentally friendly technology that provides a new generation of high-efficiency zero-pollution clean energy, fuel cell technology is being increasingly used in power, power, and energy storage industries. In the fuel cell, the widely used and developed cell structure is the proton exchange membrane fuel cell (PEMFC).

The proton exchange membrane fuel cell is a power generation device that directly converts the chemical energy of fuel and electrolyte into electrical energy. For the operation of the fuel cell, the water conductivity of the proton exchange membrane is an important parameter affecting its performance. According to domestic and foreign experimental data, the fuel cell works at 60°C and the gas humidity is between 80% and 100%, and the reaction efficiency is the highest. If the reaction gas is too dry, there will be too few water molecules in the proton exchange membrane, which will cause the fuel cell to work. Efficiency drops, and may cause damage to the exchange membrane; and excessive humidification of the reaction gas will cause the performance of the battery system to deteriorate due to "flooding" and other reasons. It can be seen that the humidification system of the fuel cell has a greater impact on the overall performance during operation.

In the current oxygen reaction gas supply of the fuel cell system, the air provided by the high-speed and large-flow air compressor is used. Among them, the air part is used for the chemical reaction of the fuel cell to generate electricity, and the rest contains more reaction water. When the air compressor is working, its outlet air temperature is very high (usually as high as about 120-130 °C), which requires cooling the air entering the fuel cell stack to meet the normal level of the stack. The working temperature is usually about 40 to 50 °C, and the necessary air cooling system is added to cool and humidify the dry and hot air entering the stack to ensure the normal operation of the fuel cell.

For the humidification system of the fuel cell, most of the current technical aspects still use humidifiers to humidify the dry and hot air, which are mainly divided into two categories: external humidification and internal humidification. , relying on the gas barrier properties of the membrane and the concentration diffusion of water in the membrane to achieve humidification; while external humidification mainly adopts methods including bubbling humidification, liquid water jet humidification, wet membrane humidification, hollow fiber humidification and steam injection humidification. Humidifier for humidification.

The cooling system and humidification system of the hot air provided by the air compressor in the existing fuel cell system are a set of relatively independent systems. Most of the cooling of the air at the outlet of the air compressor is performed by an intercooler, which requires an intercooler. A complete set of cooling systems, including cooling water pumps, intercoolers, cooling fans, pipes and water tanks, etc.; and the humidification of dry and hot air is done by using an external humidifier or by using fuel cell exhaust air for self-humidification. Relatively speaking, no matter which humidification method is, it is independent of the air cooling system, which increases the complexity of the fuel cell system to a certain extent, also takes up a lot of space, and increases the failure rate of the system. and the cost of the system; from the aspects of cost and the simplicity and practicability of the system, there is a need to improve and optimize the fuel cell system. The technical direction of high-power design is bound to require simplification and optimization of the system, reducing costs, and improving efficiency in order to increase the competitiveness of products.

SUMMARY OF THE INVENTION

In order to solve the above problems and keep up with the needs of the market and technological development, the present invention provides an integrated device for humidifying and cooling a fuel cell, which is directly connected to the fuel cell to cool and humidify the air entering the fuel cell. . It includes a front pressure plate, a front heat conduction plate, a gas-barrier water-permeable membrane, a rear heat conduction plate and a rear pressure plate, and a set of fastening bolts or steel strips which are combined and connected into one.

The humidification and cooling integrated device of the fuel cell, a set of front-end heat-conducting plates, gas-barrier water-permeable film and rear-end heat-conducting plates constitute a humidifying and cooling unit. In the humidification and cooling unit, a water flow field for heat exchange and a gas flow field for gas humidification are distributed on both sides of the front-end heat-conducting plate and the rear-end heat-conducting plate; The front-end heat-conducting plate of the cooling unit and the rear-end heat-conducting plate of the previous group of humidifying and cooling units are combined to form a "double heat-conducting plate" with a cooling water cavity inside; Between them, the three are sealed by sealing gaskets (rings), and multiple sets of humidification and cooling units are stacked in sequence to form a structure with dual functions of self-humidification and cooling. Solid form self-humidification and cooling device.

The humidification and cooling of the fuel cell are integrated into one device, and the front-end heat conduction plate of the first humidification and cooling unit is attached to the gas-barrier water-permeable membrane to form a group of cavities passing through the dry and hot air flow field. ; The gas-barrier water-permeable film of the first humidifying and cooling unit is attached to the rear heat-conducting plate to form a group of cavities that pass through the air flow field of the tail exhaust of the stack; the rear-end heat conduction of the first humidifying and cooling unit The plate is attached to the front-end heat-conducting plate of the second humidifying and cooling unit, and a group of cavities passing through the cooling water flow field are formed in the middle to form a "double heat-conducting plate";

Further, in the above-mentioned integrated device for humidifying and cooling the fuel cell, three first openings are arranged on the left side of the front pressure plate, which are respectively used as the inlets for the fuel gas, cooling water and dry hot air required for the operation of the fuel cell. ; The right side of the front pressure plate is provided with three second openings, which are respectively used as the outlets of the fuel gas tail exhaust, cooling water and air exhaust exhaust required for the operation of the fuel cell.

Further, the above-mentioned integrated device for humidifying and cooling a fuel cell constitutes a set of front-end heat-conducting plates, gas-barrier water-permeable membranes, and rear-end heat-conducting plates of a set of humidifying and cooling units. The first opening, after multiple sets of humidification and cooling units are connected and combined, are respectively used as channels for fuel gas, cooling water and dry hot air supplied to the stack, as well as for the exhaust air (which has not interacted with the dry hot air) through the stack tail. first channel;

The three first openings on the left side of the front pressure plate are connected with three channels (fuel gas, cooling water and dry hot air) in multiple groups of humidification and cooling units, wherein the fuel gas channel is a through hole channel and the cooling water channel It is communicated with the cooling water cavity inside each group of "double heat-conducting plates"; the dry and hot air channel is communicated with the cavity of the dry and hot air flow field of each group of humidification and cooling units; the stack tail exhaust air channel (first channel) is connected with The cavities of the tail exhaust air flow field of each group of humidification and cooling units are connected; the four groups of channels are isolated from other cavities or channels by sealing rings (gaskets); the tail exhaust air channel (first channel) is at the front pressure plate. form a blind block.

Further, the above-mentioned integrated device for humidifying and cooling a fuel cell constitutes a set of front-end heat-conducting plates, gas-barrier water-permeable membranes, and rear-end heat-conducting plates of a set of humidifying and cooling units. The second opening, after multiple sets of humidification and cooling units are connected and combined, serve as the passages for fuel gas, cooling water return water and wet and cold air (after the dry hot air interacts with the stack tail exhaust) respectively, and the electric The second passage for tail exhaust air (after interacting with hot dry air);

The three second openings on the right side of the front pressure plate are connected with three channels (fuel gas exhaust, cooling water return water and stack exhaust air) in multiple groups of humidification and cooling units, wherein the fuel gas exhaust channel It is a through-hole channel; the cooling water return channel is communicated with the cooling water cavity of each group of humidification and cooling units; the tail exhaust air channel (second channel) is communicated with the cavity of the tail exhaust air flow field of each group of humidification and cooling units ; The channel of wet and cold air is communicated with the cavity of the dry and hot air flow field of each group of humidification and cooling units, and the four groups of channels are isolated from other cavities or channels by sealing rings (gaskets); the channel of wet and cold air is in the front platen A blind block is formed.

Further, in the above-mentioned integrated device for humidifying and cooling a fuel cell, the rear pressure plate is connected to the front end plate of the stack. The left side of the rear pressure plate is provided with three first openings, which are respectively used as the outlet for providing fuel gas and cooling water for the stack and the inlet for exhaust air at the tail of the stack, and the fuel gas inlet and cooling water inlet of the front end plate of the stack respectively. And the tail exhaust air outlet is connected;

The three first openings of the rear platen are connected to the left three channels (fuel gas, cooling water and tail exhaust air) in multiple sets of humidification and cooling units, and the last set of humidification and cooling units are used as channels for dry and hot air , the channel forms a blind block at the rear pressure plate.

Further, in the above-mentioned integrated device for humidifying and cooling the fuel cell, three second openings are arranged on the right side of the rear pressure plate, which are used as the fuel gas tail exhaust and cooling after the reaction for the fuel cell to provide work respectively. The inlet of the water return water and the outlet of the oxygen (wet and cool air) supplied to the fuel cell are connected with the fuel gas tail discharge port, the cooling water outlet and the moist and cool air inlet of the front panel of the stack;

The three second openings of the rear pressure plate are connected with the three right channels (fuel gas tail exhaust, cooling water return water and wet cold air) in the multiple sets of humidification and cooling units, and the last set of humidification and cooling units is used as the tail exhaust The second passage of air, where the passage forms a blind block on the rear platen.

Preferably, the above-mentioned integrated device for humidification and cooling of a fuel cell, a gas-barrier water-permeable membrane for water permeation, can use a (not limited to) a porous support body wrapped by a water-permeable membrane. wet film structure.

Preferably, the porous support body is a foamed metal structure or a wire mesh structure.

Preferably, the humidification and cooling of the fuel cell are integrated into one device, and the left and right sides thereof are also provided with positioning plates for assembling and positioning.

Compared with the prior art, the present invention has the following technical effects:

The invention provides an integrated device for humidifying and cooling a fuel cell. The integrated design of humidifying and cooling a fuel cell system can be directly combined with a fuel cell, and a cooling system is shared with it. The hot air is cooled, and the water in the exhaust air of the fuel cell is used to humidify the dry and hot air entering the stack to achieve the dual effect of cooling and self-humidification, which not only reduces the cost of the intercooler/or humidifier components and the humidification water pump. It can greatly simplify the design of the fuel cell system, reduce the complexity and manufacturing cost of the system, save space, and greatly improve the power density of the fuel cell system, which has very good practical value and reference significance.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained from these drawings without any creative effort. In the attached picture:

1 is a schematic structural diagram of a device with humidifying and cooling effects provided by a preferred embodiment of the present invention, wherein only one group of humidifying and cooling units is used as a schematic diagram;

2 is a schematic diagram of the self-humidification and cooling with humidification and cooling effect devices provided by a preferred embodiment of the present invention, wherein only two sets of humidification and cooling units are used for illustration and description;

3 is a schematic diagram of the flow direction and structural principle of fuel gas, oxygen (air) and cooling water with humidification and cooling effect devices provided by the preferred embodiment of the present invention; wherein, only two sets of humidification and cooling units are used as illustrations and explanations ;

4 is a schematic diagram of the flow direction and structural principle of the device with humidification and cooling effects provided by the preferred embodiment of the present invention, and the fuel gas, oxygen (air) and cooling water after being combined with the stack;

FIG. 5 is a schematic diagram of a wet film structure of a porous support body wrapped by a water permeable film according to a preferred embodiment of the present invention.

Detailed ways

The following will describe in detail an integrated device for humidifying and cooling a fuel cell provided by the present invention with reference to FIGS. 2 to 5 . This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation is given. mode and specific operation process, but the protection scope of the present invention is not limited to the following embodiments, and those skilled in the art can modify and refine it within the scope of not changing the spirit and content of the present invention.

Example 1

Please refer to FIG. 2 to FIG. 5 , an integrated device for cooling, humidifying and collecting fuel cells. This device is an internal humidification and cooling system. Cooling is carried out, and the dry and hot air entering the stack is humidified by the water produced by the stack itself. The structure of the device includes a front pressure plate 1 , a front heat conduction plate 2 , a gas-barrier water-permeable film 3 , a rear heat conduction plate 4 , a sealing ring (gasket) 5 , a rear pressure plate 6 , a bolt group 7 and left and right positioning plates 8 .

A set of front-end heat-conducting plates 2, gas-barrier water-permeable films 3 and rear-end heat-conducting plates 4 constitute a set of humidifying and cooling units; The water flow field for heat exchange and the gas flow field for gas humidification; based on the implementation of the process, the rear heat conduction plate 4 of the former group of humidification and cooling units can be combined with the front end heat conduction plate 2 of the latter group of humidification and cooling units. , a cavity with cooling water is arranged inside, forming a "double heat conduction plate". The gas-barrier water-permeable membrane is located between the "double heat-conducting plates", and the three are sealed by sealing gaskets (rings) 5. Multiple sets of humidification and cooling units are stacked in sequence to form a structure with dual functions of self-humidification and cooling. The front pressure plate 1 . The rear pressing plate 6 is connected and fastened by a plurality of sets of bolts 7 to form a self-humidifying and cooling device.

Further, the left side of the front pressure plate 1 is provided with three first openings, which are respectively used as an inlet for fuel gas provided to the stack, an inlet for cooling water (providing stack cooling and hot air cooling), and an inlet for cooling water. The inlet of the hot air; the right side of the front pressure plate is provided with three second openings, which are respectively used for the outlet of the fuel gas at the tail of the stack, the outlet for the cooling water and the outlet for the air tail.

The left side of the rear pressing plate 6 is provided with three first openings, which are respectively used as an outlet for fuel gas provided to the stack, an outlet for providing cooling water for the stack, and an inlet for exhaust air at the tail of the stack; There are three second openings on the right side, which are respectively used for the inlet of the fuel gas at the tail of the stack, the inlet for the cooling return water of the stack, and the outlet for the wet and cold air into the stack.

Further, the front pressure plate 1 is connected with the front-end heat-conducting plate 2 of the first group of humidifying and cooling units, and a cavity for cooling water is formed between the two; the front-end heat-conducting plate 2 of the first group of humidifying and cooling units and its gas-barrier water-permeable film 3 are connected to each other, and a cavity for passing dry and hot air is formed between them; the gas-barrier water-permeable membrane 3 of the first group of humidifying and cooling units is connected to the heat-conducting plate 4 at the rear end, and the air passing through the tail of the stack is formed between the two ( The cavity containing more water) is sealed by a sealing ring (gasket) 5 between the cavities;

The rear-end heat-conducting plate 4 of the first group of humidifying and cooling units is connected to the front-end heat-conducting plate 1 of the second group of humidifying and cooling units, and a cavity for passing cooling water is formed between them. Double thermal plate".

According to this, multiple groups of humidification and cooling units are stacked in sequence until the rear end heat conduction plate 4 of the last group of humidification and cooling units is connected to the rear pressure plate 6, and a cavity for passing cooling water is formed between the two, and a sealing ring (gasket) 5 is formed between them. Seal.

Further, the front-end heat-conducting plate 2 , the gas-barrier water-permeable film 3 and the rear-end heat-conducting plate 4 that constitute a group of humidifying and cooling units are respectively provided with four first openings on their left sides, which are superimposed and combined into multiple groups of humidification. , After the cooling units are assembled, four channels are formed, three of which are respectively connected with the three first openings of the front platen 1 to form a fuel gas channel, a cooling water channel and a dry and hot air channel, which are respectively connected with each group of humidification. . The cooling water cavity of the cooling unit is communicated with the dry and hot air cavity, wherein the fuel gas is a through-hole channel, and each channel is sealed by a sealing ring (gasket) 5;

The four channels on the left side formed by the combination of multiple groups of humidification and cooling units, three of which are connected with the three first openings of the rear pressure plate 6 respectively, constitute the fuel gas channel, the cooling water channel and the stack tail row The air channel is respectively connected with the cooling water cavity of each group of humidification and cooling units and the stack exhaust air cavity, wherein the fuel gas is a through hole channel, and the sealing ring (gasket) 5 is used for sealing between each channel;

Further, the dry and hot air passages that communicate with the dry and hot air cavities of each group of humidification and cooling units from the inlet on the left side of the front platen 1 are blocked at the rear platen 6, and pass through the dry and hot air cavities of each group of humidification and cooling units. The body is connected to the wet and cold air passage on the right side (described later).

The stack tail exhaust air channel (the first channel) that communicates with the stack tail exhaust air cavity of each group of humidification and cooling units from the left side inlet of the rear pressure plate 6 is blocked at the front pressure plate 1, and through the humidification and cooling units of each group The stack tail exhaust air cavity of the cooling unit is communicated with the stack tail exhaust air passage (second passage) on the right side (described later).

Further, the front-end heat-conducting plate 2, the gas-barrier water-permeable film 3 and the rear-end heat-conducting plate 4 that constitute a group of humidification and cooling units are respectively provided with four second openings on the right side thereof, which are superimposed and combined into multiple groups of humidification. After the cooling units are assembled, four channels are formed, three of which are respectively connected with the three second openings of the rear platen 1 to form a fuel gas tail exhaust channel, a cooling water return channel and a wet and cold air channel, which are respectively connected with The cooling water cavity of each group of humidification and cooling units is communicated with the dry and hot air cavity (the wet and cold air after interacting with the humid air), in which the fuel gas tail is a through-hole channel, and a sealing ring (gasket) is passed between the channels. 5 to seal;

The stack tail exhaust air cavities of each group of humidification and cooling units communicate with the stack tail exhaust air channel (second channel) on the right side, which is blocked at the rear pressure plate 6, and the front pressure plate 1 is connected to the stack tail exhaust air channel. The outlet is connected to discharge tail exhaust air.

The wet and cold air passage connected to the right side is blocked at the front platen 1 through the dry and hot air cavities of each group of humidification and cooling units (the wet and cold air after interacting with the wet air), and communicated with the wet and cold air outlet at the rear platen 6 , used to supply cool and humid air to the stack.

Please refer to Figure 3 for the schematic diagram of the flow direction and structure of each medium. The schematic diagram of this principle is only an embodiment, and is not limited to various combinations of channels.

Dry and hot air cooling and humidification working principle:

Cooling working principle: Dry and hot air enters from the left side inlet of the front platen, passes through the dry air channel composed of the humidification and cooling units of each group on the left, and is attached to each group by the "double heat-conducting plate" and the gas-barrier water-permeable film. The left side of the formed dry and hot air cavity is communicated, and the dry air channel is blocked on the left side of the rear pressing plate. The dry and hot air passes through the multiple groups of cavities to reach the air channel on the right which is composed of the humidification and cooling units; Low-temperature cold air is formed in the channel to achieve cooling effect.

Humidification working principle: When the dry and hot air passes through the dry and hot air cavity composed of multiple sets of "double heat-conducting plates" and the gas-barrier water-permeable film, and reaches the air channel on the right, which is composed of each set of humidification and cooling units, it will The tail exhaust air (containing a large amount of water) of the tail exhaust air channel formed by each group of double heat-conducting plates and the gas-barrier water-permeable membrane interacts with the gas-barrier water-permeable membrane, and through the penetration of water and the diffusion of the concentration difference, the dry and hot air is realized. The effect of humidification;

In the present invention, the gas-barrier water-permeable membrane can be replaced by a wet membrane structure with humidification effect to increase its practicality and economy, and a detailed description of this humidification structure is given below.

Wet film structure

In this solution, the wet film structure can be a composite wet film structure with a certain supporting function. As shown in FIG. 5 , the composite wet film structure is composed of a porous support body 32 wrapped by a water permeable film 31 . The support body 32 is a sheet metal foam structure or a wire mesh structure, preferably a sheet metal foam nickel as the support body.

Embodiment 2

1 to 4 , the present embodiment provides a plate-type self-humidifying and cooling device for a fuel cell system, including a front pressure plate 1 , at least one humidification and cooling unit and a rear pressure plate 6 stacked in sequence. Several bolt groups 7 are arranged between the front pressure plate 1 and the rear pressure plate 6 for pressing and fixing the front pressure plate 1 and the rear pressure plate 6, so as to realize the pressing of multiple humidification and cooling units.

The humidifying and cooling unit includes a front-end heat-conducting plate 2 , a gas-barrier water-permeable film 3 and a rear-end heat-conducting plate 4 that are stacked in sequence. Both sides of the front-end heat-conducting plate and the rear-end heat-conducting plate are provided with a flow field composed of flow channels. The flow field of the front-end heat-conducting plate 2 cooperates with one side of the gas-barrier water-permeable film 3 to form a dry hot air cavity, and the rear-end heat-conducting plate 4 The flow field of the air barrier cooperates with the other side of the gas-barrier water-permeable membrane 3 to form a humid air cavity. That is, a corresponding flow field formed by a flow channel is opened on the opposite surfaces of the front-end heat-conducting plate 2 and the rear-end heat-conducting plate 4, and the two flow fields cooperate to form a hollow cavity, and then the gas-barrier water-permeable membrane 3 is arranged in the hollow cavity. In the middle of the cavity, the hollow cavity is divided into the above-mentioned dry hot air cavity and moist air cavity.

At the same time, in the adjacent humidification and cooling units, the rear heat conduction plate 4 of the previous humidification and cooling unit cooperates with the front heat conduction plate 2 of the latter humidification and cooling unit to form a cooling water cavity. The front heat conduction plate 2 of the frontmost humidification and cooling unit cooperates with the front pressure plate 1 to form a cooling water cavity, and the rear heat conduction plate 4 of the last humidification and cooling unit cooperates with the rear pressure plate 6 to form a cooling water cavity. The setting method here is the same as that of the dry and hot air cavity and the humid air cavity above. cooling water chamber.

The plate-type self-humidifying cooling device further includes a dry and hot air input channel, a cooling water input channel, a tail exhaust air input channel, a wet cold air output channel, a cooling water output channel and a tail exhaust air output channel.

Wherein, the dry and hot air input channels are respectively communicated with one side of each dry and hot air cavity. The cooling water input channels are respectively communicated with one side of each cooling water cavity. The tail exhaust air input channels are respectively communicated with one side of each humid air cavity. The wet and cold air output channels are respectively communicated with the other side of each dry and hot air cavity. The cooling water output channels are respectively communicated with the other side of each cooling water cavity. The tail exhaust air output channels are respectively communicated with the other side of each humid air cavity.

The plate-type self-humidifying cooling device of this embodiment includes two functions of cooling and humidifying the dry and hot air entering the dry and hot air cavity during use. Among them, the cooling function is realized by the cooling water input channel and the cooling water output channel respectively connected with the cooling water cavity. The cooling water in the cooling water cavity is constantly flowing and updated to maintain a lower temperature, and can pass through the front heat conduction plate 2 or the cooling water output channel. The rear heat conducting plate 4 exchanges heat with the dry hot air in the adjacent dry hot air cavity, so that the temperature of the dry hot air is lowered. The humidification function is realized by the tail exhaust air input channel, the tail exhaust air output channel and the gas-barrier water-permeable membrane 3 communicating with the humid air cavity. The tail exhaust air input channel is connected to the tail exhaust air output end of the fuel cell. , and the tail exhaust air of the fuel cell is the air containing more reaction water, then the tail exhaust air can transmit the water vapor to the adjacent dry hot air cavity through the gas-barrier water-permeable membrane 3 in the humid air cavity. The dry and hot air inside is humidified, so as to finally obtain the required wet and cold air and output it into the fuel cell through the wet and cold air output channel. It not only reduces the use of intercooler/or humidifier components and humidification water pump, but also greatly simplifies the design of the fuel cell system, reduces the complexity and manufacturing cost of the system, saves space, and greatly improves the power density of the fuel cell system. , has very good practical value and reference significance.

The specific structure of the plate-type self-humidification cooling device for the fuel cell system of this embodiment will be further described below:

In this embodiment, three groups of corresponding first openings are formed on the first sides of the front pressure plate 1 , the front heat conduction plate 2 , the gas-barrier water-permeable film 3 , the rear heat conduction plate 4 and the rear pressure plate 6 . The first openings cooperate to form the above-mentioned dry and hot air input channel, cooling water input channel and tail exhaust air input channel, respectively. The second side of the front pressure plate 1, the front heat conduction plate 2, the gas-barrier water-permeable film 3, the rear heat conduction plate 4 and the rear pressure plate 6 can also be provided with three groups of corresponding second openings, and the three groups of corresponding second openings are respectively The wet and cold air output channel, the cooling water output channel and the tail exhaust air output channel are formed together. Because the pressing plate and the heat-conducting plate are closely attached or even fixed, several groups of first and second openings for coaxial lines are formed on them to obtain the required channels.

Among them, the dry and hot air input channel is located on one side of the front platen 1 and communicated with the external air compressor, and the dry and hot air input channel is located on one side of the rear platen 6 and blocked, so that the dry and hot air can all enter each dry and hot air through the dry heat input channel. in the hot air chamber. The cooling water input channel is located on one side of the front platen 1 and communicates with the external water supply device, and the cooling water input channel is located on the side of the rear platen 6 and communicates with the cooling water input end of the fuel cell, that is, part of the cooling water passes through the cooling water cavity. Dry hot air is used for cooling, and part of the cooling water enters the fuel cell for cooling. The tail exhaust air input channel is located on one side of the front pressure plate 1 and blocked, and the tail exhaust air input channel is located on the side of the rear pressure plate 6 and communicates with the tail exhaust air output end of the fuel cell, so as to ensure that the tail exhaust air from the fuel cell can be fully Enter the humid air cavity to play a role.

The wet and cold air output channel is located on one side of the front platen 1 and blocked, and the wet and cold air output channel is located on the side of the rear platen 6 and communicates with the wet and cold air input end of the fuel cell, so that the wet and cold air obtained after cooling and humidification can be output to the fuel cell and Do not leak. The cooling water output channel is located on one side of the front pressure plate 1 and communicates with the external water supply device, and the cooling water output channel is located on the side of the rear pressure plate 6 and communicates with the cooling water output end of the fuel cell. The tail exhaust air output channel is located on the side of the front pressure plate 1 and communicates with the outside atmosphere, and the tail exhaust air input channel is located at the side of the rear pressure plate 6 and blocked.

Further, in order not to add additional pipelines and reduce the overall volume of the fuel cell, in this embodiment, on the basis of the above, the front pressure plate 1, the front heat conduction plate 2, the gas-barrier water-permeable membrane 3, the rear The fourth group of corresponding first openings on the first side of the end heat-conducting plate 4 and the rear pressure plate 6, as well as openings in the front pressure plate 1, the front heat-conducting plate 2, the gas-barrier water-permeable film 3, the rear-end heat-conducting plate 4 and the rear pressure plate The fourth group of corresponding second openings on the second side of 6.

The corresponding first openings of the fourth group cooperate to form a hydrogen input channel. The hydrogen input channel is located on one side of the front pressure plate 1 and communicates with the external hydrogen supply device, and the hydrogen input channel is located on the side of the rear pressure plate 6 and communicates with the hydrogen input end of the fuel cell. The corresponding second openings of the fourth group cooperate to form a hydrogen tail exhaust channel. The hydrogen tail exhaust channel is located on one side of the rear pressure plate 6 and communicates with the hydrogen output end of the fuel cell. Therefore, the input pipeline and the output pipeline of hydrogen are also integrated into the plate-type self-humidification cooling device of this embodiment, and the volume is reduced.

In this embodiment, in order to ensure the airtightness of the multiple channels formed between the pressing plate and each heat-conducting plate, the humidifying and cooling unit may further include several sealing members. The seals are respectively arranged at the junction of the first opening and the second opening between the front-end heat-conducting plate 2 and the gas-barrier water-permeable film 3, and the gas-barrier water-permeable film 3 and the rear heat-conducting plate 4. between the junction of the first opening and the junction of the second opening. That is, the sealing ring is arranged between the two adjacent plates to seal the corresponding channel to avoid leakage. In order to facilitate positioning and installation, sealing grooves can be further provided at the corresponding positions of the pressing plate and the heat conducting plate. At the same time, sealing members can also be arranged around the cooling water cavity, the dry and hot air cavity and the moist air cavity, so as to ensure the sealing performance of each cavity.

In this embodiment, in order to realize the communication between each channel and the corresponding cavity, a solution is provided, that is, a first groove is formed on the front heat conduction plate 2 and/or the rear heat conduction plate 4, and a first groove is formed on the front heat conduction plate 2 and/or the rear heat conduction plate 4 Two ends of a groove are respectively communicated with the cooling water input channel and the cooling water cavity.

A second groove is formed on the front heat conducting plate 2 and/or the rear heat conducting plate 4, and both ends of the second groove communicate with the cooling water output channel and the cooling water cavity respectively.

A third groove and a fourth groove are opened on the front heat conducting plate 2 . Both ends of the third groove are respectively communicated with the dry and hot air input channel and the dry and hot air cavity. Both ends of the fourth groove are respectively communicated with the wet and cold air output channel and the dry and hot air cavity.

A fifth groove and a sixth groove are formed on the rear heat conducting plate 4 . Both ends of the fifth groove are respectively communicated with the tail exhaust air input channel and the humid air cavity. Both ends of the sixth groove are respectively communicated with the tail exhaust air output channel and the humid air cavity.

In this embodiment, the cooling water cavity, the dry and hot air cavity, and the moist air cavity are all constituted by the flow field formed by the set flow channel, and the flow channel is a serpentine flow field or a multi-channel parallel flow field or an alternating flow field. Finger-shaped flow field, so that the effect of heat exchange and humidification is better.

In this embodiment, the adjacent front-end heat-conducting plates 2 and the rear-end heat-conducting plates 4 are connected by welding, bonding, or integrally formed by stamping. Certainly, in other embodiments, the connection manners may also be various, which are not specifically limited herein.

In this embodiment, several positioning plates 8 may also be included. The positioning plates 8 are arranged along the stacking direction of the humidification and cooling units, and the positioning plates 8 are fixed on the front pressure plate 1 and the rear pressure plate 6, so as to determine the front pressure plate 1 and the rear pressure plate 6. The relative position between them can also guide the installation and fixation of the humidification and cooling unit.

In this embodiment, the gas-barrier water-permeable membrane 3 may specifically be a wet-film structure, the wet-film structure includes a water-permeable membrane and a support body, the water-permeable membrane covers the support body, and the support body is provided with a plurality of communication holes. Specifically, the wet film structure may be a composite wet film structure with a certain supporting function. As shown in FIG. 5 , the composite wet film structure is composed of a porous support body 32 wrapped by a water permeable film 31 . The microporous support body 32 is a sheet metal foamed metal structure or a wire mesh structure, preferably a sheet metal foamed nickel as the support body.

Embodiment 3

This embodiment provides a humidification and cooling unit used in the above-mentioned first or second embodiment. Specifically, it may include a front-end heat-conducting plate 2 , a gas-barrier water-permeable film 3 and a rear-end heat-conducting plate 4 that are stacked in sequence. Both sides of the front-end heat-conducting plate and the rear-end heat-conducting plate are provided with a flow field composed of flow channels. The flow field of the front-end heat-conducting plate 2 cooperates with one side of the gas-barrier water-permeable film 3 to form a dry hot air cavity, and the rear-end heat-conducting plate 4 The flow field of the air barrier cooperates with the other side of the gas-barrier water-permeable membrane 3 to form a humid air cavity. The outward-facing sides of the front-end heat-conducting plate 2 and the rear-end heat-conducting plate 4 are both provided with a flow field formed by matching the cooling water flow channels forming the cooling water cavity.

At least three groups of corresponding first openings are provided on the first sides of the front-end heat-conducting plate 2, the gas-barrier water-permeable film 3 and the rear-end heat-conducting plate 4, and the three groups of corresponding first openings are respectively matched to form dry hot air input holes, Cooling water input hole and tail exhaust air input hole. The dry and hot air input hole communicates with the dry and hot air cavity. The cooling water input hole communicates with the cooling water cavity on the front heat conducting plate 2 and/or the rear heat conducting plate 4 . The tail exhaust air input hole is communicated with the humid air cavity.

At least three groups of corresponding second openings are formed on the second side of the front heat conduction plate 2, the gas-barrier water-permeable film 3 and the rear heat conduction plate 4, and the three groups of corresponding second openings are respectively matched to form wet and cold air output holes, cooling Water output holes and tail exhaust air output holes. The wet and cold air output holes are communicated with the dry and hot air cavity. The cooling water output hole communicates with the cooling water cavity on the front heat conducting plate 2 and/or the rear heat conducting plate 4 . The tail exhaust air output hole is communicated with the humid air cavity.

Based on the above structure, in the humidifying and cooling unit of this embodiment, the dry hot air enters the dry hot air cavity through the dry hot air input hole, and the dry hot air in the dry hot air cavity can be cooled by the cooling water in the cooling water tank to realize The function of cooling; the tail exhaust air of the fuel cell with moisture enters the wet air cavity through the tail exhaust air input hole, and the moisture enters the dry hot air cavity through the gas barrier water permeable membrane 3 to humidify the dry hot air, thereby The moist and cold air is obtained and output through the moist and cold air output hole.

The specific structure of the humidification and cooling unit of this embodiment will be further described below:

In the present embodiment, the humidifying and cooling unit may further include a fourth group of corresponding first openings opened on the first sides of the front heat conducting plate 2 , the gas-barrier water permeable film 3 and the rear heat conducting plate 4 . and a fourth group of corresponding second openings opened on the second sides of the front heat conducting plate 2 , the gas-barrier water-permeable film 3 and the rear heat conducting plate 4 . The corresponding first openings of the fourth group cooperate to form hydrogen input holes. The corresponding second openings of the fourth group cooperate to form hydrogen tail exhaust holes. Therefore, the input pipeline and the output pipeline of hydrogen are also integrated into the humidification and cooling unit of this embodiment, so that the volume is reduced.

In this embodiment, the humidifying and cooling unit further includes several sealing members 5 . The sealing member 5 is respectively arranged at the junction of the first opening and the junction of the second opening between the front-end heat conduction plate 2 and the gas-barrier water-permeable film 3, and the gas-barrier water-permeable film 3 and the rear heat-conducting plate. 4 between the junction of the first opening and the junction of the second opening. That is, a sealing ring is arranged between two adjacent plates to seal the corresponding holes to avoid leakage. In order to facilitate positioning and installation, a sealing groove is provided in the corresponding position of the heat conducting plate. At the same time, sealing members 5 can also be arranged around the cooling water cavity, the dry and hot air cavity and the moist air cavity, so as to ensure the sealing performance of each cavity.

In this embodiment, the front heat conducting plate 2 and/or the rear heat conducting plate 4 are provided with a first groove, and both ends of the first groove are respectively communicated with the cooling water input hole and the cooling water cavity. The front heat conducting plate 2 and/or the rear heat conducting plate 4 are provided with a second groove, and two ends of the second groove are respectively communicated with the cooling water output hole and the cooling water cavity. The front heat conducting plate 2 is provided with a third groove and a fourth groove. Two ends of the third groove are respectively communicated with the dry and hot air input hole and the dry and hot air cavity. Both ends of the fourth groove are respectively communicated with the wet and cold air output hole and the dry and hot air cavity. The rear heat conducting plate 4 is provided with a fifth groove and a sixth groove. Both ends of the fifth groove are respectively communicated with the tail exhaust air input hole and the humid air cavity. Both ends of the fourth groove are respectively communicated with the tail exhaust air output hole and the humid air cavity.

Embodiment 4

This embodiment provides a method for humidifying and cooling dry hot air, which is used to humidify and cool dry hot air output from an air compressor and obtain wet and cold air output to a fuel cell, which is applied to the plate type in Embodiment 1 or Embodiment 2. Self-humidification cooling device, its steps are as follows:

Humidification step: using the tail exhaust air with moisture output after the fuel cell reaction passes through the gas-barrier water-permeable membrane 3 to exchange moisture for the dry and hot air. Specifically, the humidification step is realized by arranging two dry and hot air chambers and a humid air chamber separated by a gas-barrier water-permeable membrane 3 , the dry and hot air chamber introduces dry and hot air, and the wet air chamber introduces moisture with moisture. The moisture in the tail exhaust air will enter the dry and hot air cavity through the gas-barrier water-permeable membrane 3 to humidify the dry and hot air, so as to achieve the purpose of humidification.

Cooling step: use cooling water to exchange heat with the dry hot air through the front heat conduction plate 2 or the rear heat conduction plate 4 . Specifically, the cooling step is realized by arranging a cooling water cavity separated by a heat conducting plate and a dry hot air cavity, diverting the cooling water originally input to the fuel cell, and guiding part of the cooling water into the cooling water cavity, and the cooling water is cooled by the cooling water. The water exchanges heat with the dry hot air through the heat-conducting plate, so as to achieve the purpose of cooling.

Wherein, the dry and hot air obtains the required wet and cold air through the humidifying step and the cooling step. The humidifying step and the cooling step may be performed simultaneously or in steps, which are not specifically limited herein. The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and the technical equivalents thereof, they still fall within the protection scope of the present invention.

Claims

A plate-type self-humidifying and cooling device is characterized in that, it is used in a fuel cell system and includes a front pressure plate, at least one humidification and cooling unit and a rear pressure plate stacked in sequence; several sets of bolts are arranged between the front pressure plate and the rear pressure plate , for pressing and fixing the front pressing plate and the rear pressing plate;

Wherein, the humidification and cooling unit includes a front-end heat-conducting plate, a gas-barrier water-permeable film, and a rear-end heat-conducting plate stacked in sequence; both sides of the front-end heat-conducting plate and the rear-end heat-conducting plate are provided with a flow field composed of flow channels , the flow field of the front-end heat-conducting plate cooperates with one side of the gas-barrier water-permeable film to form a dry hot air cavity, and the flow field of the rear-end heat-conducting plate cooperates with the other side of the gas-barrier water-permeable film to form a humid air cavity;

In the adjacent humidification and cooling units, the flow field of the rear heat conduction plate of the former humidification and cooling unit cooperates with the flow field of the front end heat conduction plate of the latter humidification and cooling unit to form a cooling water cavity; The flow field of the front heat conduction plate of the humidification and cooling unit cooperates with the front pressure plate to form a cooling water cavity, and the flow field of the rear heat conduction plate of the last humidification and cooling unit cooperates with the rear pressure plate to form a cooling water cavity ;

Also includes dry and hot air input channel, cooling water input channel, tail exhaust air input channel, wet cold air output channel, cooling water output channel and tail exhaust air output channel;

The dry and hot air input channels are respectively communicated with one side of each dry and hot air cavity; the cooling water input channels are respectively communicated with one side of each of the cooling water chambers; the tail exhaust air input channel respectively communicated with one side of each humid air cavity;

The wet and cold air output channels are respectively communicated with the other side of each dry and hot air cavity; the cooling water output channels are respectively communicated with the other side of each of the cooling water chambers; the tail exhaust air is output The channels are respectively communicated with the other side of each humid air cavity.
The plate-type self-humidifying cooling device according to claim 1, wherein the first pressure plate of the front platen, the front-end heat-conducting plate, the gas-barrier water-permeable film, the rear-end heat-conducting plate and the rear platen At least three sets of corresponding first openings are provided on the side, and the three sets of corresponding first openings cooperate to form the dry hot air input channel, the cooling water input channel and the tail exhaust air input channel respectively;

The dry and hot air input channel is located on one side of the front platen and communicates with an external air compressor, the dry and hot air input channel is located on one side of the rear platen to block; the cooling water input channel is located on the front platen. One side of the pressure plate is communicated with an external water supply device, the cooling water input channel is located on one side of the rear pressure plate and communicates with the cooling water input end of the fuel cell; the tail exhaust air input channel is located at one side of the front pressure plate to seal The tail exhaust air input channel is located on one side of the rear pressure plate and communicates with the tail exhaust air output end of the fuel cell;

The front pressure plate, the front heat conduction plate, the gas-barrier water-permeable film, the rear heat conduction plate and the second side of the rear pressure plate are provided with at least three sets of corresponding second openings, and the three sets of corresponding second openings are formed. The second openings cooperate to form the wet and cold air output channel, the cooling water output channel and the tail exhaust air output channel respectively;

The wet and cold air output channel is located at one side of the front platen and blocked, the wet and cold air output channel is located at one side of the rear platen and communicates with the wet and cold air input end of the fuel cell; the cooling water output channel is located at the One side of the front pressure plate is communicated with an external water supply device, the cooling water output channel is located on one side of the rear pressure plate and communicated with the cooling water output end of the fuel cell; the tail exhaust air output channel is located at one side of the front pressure plate In communication with the external atmosphere, the tail exhaust air input channel is located on one side of the rear pressure plate and blocked.
The plate-type self-humidifying cooling device according to claim 2, characterized in that, further comprising: the front pressure plate, the front-end heat-conducting plate, the gas-barrier water-permeable film, the rear-end heat-conducting plate, and the rear heat-conducting plate. The fourth group of the corresponding first openings on the first side of the pressing plate, and the first openings opened on the front pressing plate, the front heat conducting plate, the gas-barrier water-permeable film, the rear heat conducting plate and the rear the second openings corresponding to the fourth group of the second side of the pressing plate;

The fourth group of corresponding first openings cooperate to form a hydrogen input channel; the hydrogen input channel is located on one side of the front pressure plate and communicates with an external hydrogen supply device, and the hydrogen input channel is located on one side of the rear pressure plate communicated with the hydrogen input end of the fuel cell;

The fourth group of the corresponding second openings cooperate to form a hydrogen tail exhaust channel; the hydrogen tail exhaust channel is located on one side of the rear pressure plate and communicates with the hydrogen output end of the fuel cell.
The plate-type self-humidifying cooling device according to claim 2, wherein the humidifying and cooling unit further comprises a plurality of seals; the seals are respectively arranged between the front-end heat conducting plate and the gas-barrier water-permeable film The junction of the first opening and the junction of the second opening, and the junction of the first opening between the gas-barrier water-permeable film and the rear heat-conducting plate and the junction of the second opening.
The plate-type self-humidifying cooling device according to claim 2, wherein a first groove is formed on the front-end heat-conducting plate and/or the rear-end heat-conducting plate, and two ends of the first groove are respectively connected with the cooling water input channel communicates with the cooling water cavity;

A second groove is formed on the front-end heat-conducting plate and/or the rear-end heat-conducting plate, and two ends of the second groove are respectively communicated with the cooling water output channel and the cooling water cavity;

A third groove and a fourth groove are formed on the front heat conducting plate; both ends of the third groove are respectively connected with the dry hot air input channel and the dry hot air cavity; the fourth groove Two ends of the groove are respectively communicated with the wet and cold air output channel and the dry and hot air cavity;

The rear heat-conducting plate is provided with a fifth groove and a sixth groove; two ends of the fifth groove are respectively connected with the tail exhaust air input channel and the humid air cavity; the sixth groove Two ends of the groove are respectively communicated with the tail exhaust air output channel and the humid air cavity.
The plate-type self-humidifying cooling device according to claim 1, wherein the flow field constituting the cooling water cavity, the dry and hot air cavity and the moist air cavity is a serpentine flow field or a Multi-channel parallel flow field or interdigital flow field.
The plate-type self-humidifying cooling device according to claim 1, wherein the adjacent front-end heat-conducting plates and the rear-end heat-conducting plates are integrally formed by welding or bonding or stamping.
The plate-type self-humidifying and cooling device according to claim 1, further comprising a positioning plate, the positioning plate is arranged along the stacking direction of the humidifying and cooling units, and the positioning plate is fixed to the front pressing plate and the on the back platen.
The plate-type self-humidifying cooling device according to claim 1, wherein the gas-barrier water-permeable film is a wet-film structure, the wet-film structure comprises a water-permeable film and a support body, and the water-permeable film is wrapped on the support body , and a plurality of communication holes are opened on the support body.
A plate-type self-humidifying cooling device is characterized by comprising a front pressure plate, a front heat conduction plate, a gas-barrier water-permeable film, a rear heat conduction plate and a rear pressure plate;

The set of front-end heat-conducting plates, the gas-barrier water-permeable film and the rear-end heat-conducting plate constitute a humidification and cooling unit; multiple sets of the humidification and cooling units are stacked in sequence to form a structure with dual functions of self-humidification and cooling, and the front pressure plate A self-humidifying cooling device is formed by connecting and tightening the rear pressure plate with the back pressure plate through a plurality of sets of bolts.
A humidification and cooling unit is characterized in that it includes a front-end heat-conducting plate, a gas-barrier water-permeable film, and a rear-end heat-conducting plate that are stacked in sequence; The flow field of the front-end heat-conducting plate cooperates with one side of the gas-barrier water-permeable film to form a dry-hot air cavity, and the flow field of the rear-end heat-conducting plate cooperates with the other side of the gas-barrier water-permeable film to form a cavity. a humid air cavity; the outward-facing side of the front-end heat-conducting plate and the rear-end heat-conducting plate is provided with a flow field formed by a cooling water flow channel for cooperating with forming a cooling water cavity;

At least three groups of corresponding first openings are formed on the first side of the front-end heat-conducting plate, the gas-barrier water-permeable film, and the rear-end heat-conducting plate, and the three groups of corresponding first openings are respectively matched to form dry openings. hot air input hole, cooling water input hole and tail exhaust air input hole; the dry hot air input hole is communicated with the dry hot air cavity; the cooling water input hole is connected with the front heat conduction plate and/or the rear end The cooling water cavity on the heat conduction plate is communicated; the tail exhaust air input hole is communicated with the humid air cavity;

At least three groups of corresponding second openings are formed on the second side of the front-end heat-conducting plate, the gas-barrier water-permeable film, and the rear-end heat-conducting plate, and the three groups of corresponding second openings are respectively matched to form wet and cold Air output holes, cooling water output holes and tail exhaust air output holes; the wet and cold air output holes are communicated with the dry and hot air cavity; the cooling water output holes are connected to the front heat conduction plate and/or the rear heat conduction plate The cooling water cavity on the upper part is in communication; the tail exhaust air output hole is in communication with the humid air cavity.
The humidifying and cooling unit according to claim 11, further comprising a fourth group corresponding to the first side of the front heat conducting plate, the gas-barrier water-permeable film and the rear heat conducting plate. an opening; and a fourth group of corresponding second openings opened on the second side of the front-end heat-conducting plate, the gas-barrier water-permeable film, and the rear-end heat-conducting plate;

The corresponding first openings of the fourth group cooperate to form hydrogen input holes; the corresponding second openings of the fourth group cooperate to form hydrogen tail exhaust holes.
The humidifying and cooling unit according to claim 11, characterized in that, the humidifying and cooling unit further comprises a plurality of sealing members; the sealing members are respectively provided at all points between the front-end heat conducting plate and the gas-barrier water-permeable film. The junction of the first opening and the junction of the second opening, and the junction and the junction of the second opening.
The humidifying and cooling unit according to claim 11, wherein a first groove is formed on the front-end heat-conducting plate and/or the rear-end heat-conducting plate, and two ends of the first groove are respectively connected to the the cooling water input hole communicates with the cooling water cavity;

A second groove is formed on the front-end heat-conducting plate and/or the rear-end heat-conducting plate, and two ends of the second groove are respectively communicated with the cooling water output hole and the cooling water cavity;

A third groove and a fourth groove are opened on the front-end heat conducting plate; two ends of the third groove are respectively communicated with the dry hot air input hole and the dry hot air cavity; the fourth groove Two ends of the groove are respectively communicated with the wet and cold air output hole and the dry and hot air cavity;

The rear heat-conducting plate is provided with a fifth groove and a sixth groove; two ends of the fifth groove are respectively connected with the tail exhaust air input hole and the humid air cavity; the fourth groove Two ends of the groove are respectively communicated with the tail exhaust air output hole and the humid air cavity.
A method for humidifying and cooling dry hot air, characterized in that it is used to obtain wet and cold air output to a fuel cell, and is applied to the plate-type self-humidifying cooling device according to any one of claims 1-10, and the steps are as follows:

Humidification step: use the tail exhaust air with moisture output after the fuel cell reaction to exchange moisture with the dry and hot air through the gas-barrier water-permeable membrane;

Cooling step: use cooling water to exchange heat with the dry hot air through the front-end heat-conducting plate or the back-end heat-conducting plate;

Wherein, the dry and hot air obtains the required wet and cold air through the humidification step and the cooling step.