Fuel cell humidifier and air humidifying system

Abstract

The utility model discloses a fuel cell humidifier and an air humidifying system, the humidifier is provided with a dry gas inlet, a dry gas outlet, a wet gas inlet and a wet gas outlet to meet the general humidifying function, and is also provided with a spraying opening and a water draining opening to have liquid water spraying and water draining functions. The air humidifying system comprises a humidifier, a water segregator and a rubber pipe, the water segregator is arranged above the humidifier, an inlet of the water segregator is connected with a moisture outlet of the humidifier, an outlet of the water segregator is connected with an inlet of the turbine end of the air compressor, and a water outlet of the water segregator is connected with a spraying opening of the humidifier through the rubber pipe. Water is separated from wet air through the water segregator and sprayed to the hollow fiber pipe in the humidifier through the rubber pipe under the action of gravity, due to the fact that the hollow fiber pipe is hydrophilic, liquid water can be easily adsorbed to the membrane pipe and permeates into the hollow fiber pipe, when hot air compressed by an air compressor passes through, the liquid water can be vaporized, and the water in the hollow fiber pipe is vaporized. And a secondary humidification effect is achieved on the air.

Description

Technical Field

[0001] The utility model relates to the technical field of fuel cells, and more specifically to a fuel cell humidifier and an air humidification system. Background Art

[0002] A fuel cell system consists of parts such as a stack subsystem, a hydrogen subsystem, an air subsystem, a cooling subsystem, and an electrical subsystem. The role of the air subsystem is to provide the reactant - oxygen (from air) for the electrochemical reaction of the fuel cell stack. In order to enable the fuel cell to have the best output characteristics, the air needs to meet requirements such as pressure, flow rate, temperature, and relative humidity. Therefore, the traditional air subsystem includes components such as an air filter, an air compressor, an intercooler, a humidifier, and a silencer. In order to reduce the energy consumption of the air compressor and improve efficiency, more and more turbine expansion type air compressor solutions are adopted now, that is, energy recovery is carried out by the work of the tail exhaust waste gas to reduce power consumption. The design schematic diagram is as Figure 1 shown. The role of the air filter is to filter particulate or harmful impurities in the air; the role of the air compressor is to provide the required air flow rate and boost pressure; the role of the intercooler is to cool the boosted air to reach the target temperature; the humidifier is used to humidify the air entering the stack; the water separator is used to separate water from the wet air to avoid corrosion of the turbine; the silencer is used to eliminate noise.

[0003] A humidifier is a device used to humidify the air entering the stack. The air needs to be humidified because the electrolyte of a proton exchange membrane fuel cell needs to have a certain humidity to have better output performance. Therefore, although water is generated during the electrochemical reaction, air humidification will make the stack output performance better. However, the common problem of current humidifier products is that it is increasingly difficult to meet the demand for air humidity in the fuel cell system during high-power output.

[0004] For existing fuel cell humidifiers, for example, a Chinese patent with the authorization announcement number CN216793747U provides a fuel cell humidifier. By setting a humidification component, the gas entering the humidifier can be humidified, and a water vapor separation component is arranged inside the air outlet to separate part of the water in the gas discharged from the humidification component. At the same time, a water return port and a return water pipe are arranged at the air outlet, and the return water pipe is connected to the wet gas inlet, so as to realize the recycling of the water in the humidifier and improve the humidification efficiency. However, for the fuel cell humidifier designed by adopting this scheme, the liquid water flowing back in the return water pipe is directly connected from the wet gas inlet. Since it is necessary to ensure that the liquid level of the return water pipe is higher than the wet gas inlet, the wet gas inlet is arranged at the bottom of the humidifier. Therefore, unless the liquid water re-entering from the wet gas inlet is re-vaporized, it is difficult to diffuse into the tube membranes of each hollow fiber tube in the humidifier housing. Therefore, its secondary humidification effect is average. Therefore, the fuel cell humidifier of this patent still has difficulty meeting the demand for air humidity in the fuel cell system during high-power output.

[0005] To this end, we provide a fuel cell humidifier and an air humidification system. Summary of the Utility Model

[0006] The present utility model provides a fuel cell humidifier and an air humidification system, aiming to solve the problem that the existing fuel cell humidifier re-enters the liquid water into the humidifier through the wet air inlet, and the secondary humidification effect is average.

[0007] The present utility model adopts the following technical solutions:

[0008] A fuel cell humidifier includes a humidifier main body. Dry gas inlets and dry gas outlets are respectively arranged at the front and rear ends of the humidifier main body. Two partitions are spaced in the humidifier main body between the dry gas inlet and the dry gas outlet, so that the humidifier main body forms an exchange chamber. A plurality of hydrophilic hollow fiber tubes are arranged in parallel in the exchange chamber. Through holes are provided on the partitions at both ends of each hollow fiber tube, corresponding to and communicating with the dry gas inlet and the dry gas outlet respectively; a wet gas inlet and a wet gas outlet are communicated with the side of the exchange chamber, a spray port communicating with the exchange chamber is arranged on the top surface of the exchange chamber, and a drain port is also provided in the exchange chamber, and a drain valve is installed at the drain port.

[0009] In a preferred embodiment, two spray ports are arranged on the top surface of the above-mentioned exchange chamber, and the spray ports are arranged at intervals along the length extension direction of the hollow fiber tube.

[0010] In a preferred embodiment, the above-mentioned drain port is arranged at the bottom of the exchange chamber.

[0011] In a preferred embodiment, the above-mentioned drain valve is preferably an electromagnetic valve.

[0012] The present utility model also provides an air humidification system, which includes the above-mentioned humidifier, and also includes a water separator and a rubber hose. The water separator is arranged above the humidifier. The water separator is provided with a water separator inlet, a water separator outlet and a water outlet. The water separator inlet is connected with the wet gas outlet, the water separator outlet is connected with the inlet of the compressor turbine end, and the water outlet is connected with the spray port through the rubber hose.

[0013] Preferably, two of the above-mentioned spray ports are arranged on the top surface of the exchange chamber, and the rubber hose is Y-shaped.

[0014] Furthermore, a metal filter screen is arranged in the above-mentioned rubber hose.

[0015] It can be seen from the above description of the present utility model that compared with the prior art, the present utility model has the following advantages:

[0016] 1. The fuel cell humidifier of the utility model has a spray port added to the top surface of the exchange chamber, and the exchange chamber is also provided with a drain port, which has the functions of liquid water spraying and draining. The liquid water is sprayed onto the hollow fiber tube of the exchange chamber through the spray port. Since the membrane tube inside the humidifier is a hydrophilic hollow fiber tube, the liquid water sprayed from the top of the humidifier will be more easily adsorbed on the membrane tube and penetrate into the hollow fiber tube. When the hot air compressed by the air compressor passes through, the liquid water will be vaporized, thereby improving the secondary humidification effect on the dry air.

[0017] 2. The air humidification system of the utility model uses the water separator of the air subsystem to separate water from the air, and the separated water is sprayed onto the hollow fiber tube inside the humidifier through the hose by gravity without consuming additional energy. This design helps to increase the contact area between the liquid water and the hollow fiber tube, which is conducive to the penetration of liquid water from the outside of the membrane tube to the inside of the membrane tube, and then uses the evaporation of liquid water by compressed hot air to achieve secondary humidification of the air. If the output power of the fuel cell system is higher, the current density is greater, the required air flow and pressure are also greater, and the temperature of the air compressed by the air compressor is also higher at this time, and the amount of liquid water vaporization will also increase accordingly. Therefore, when the power is higher, the secondary humidification effect of the air humidification system of the utility model is better, which can effectively improve the problem of low humidification efficiency under high power output state. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the design principle diagram of the air subsystem in the background technology.

[0019] Figure 2 This is a schematic structural diagram of a fuel cell humidifier according to a first embodiment of the utility model.

[0020] Figure 3 for Figure 2 sectional view of .

[0021] Figure 4 This is a schematic diagram of the structure of the air humidification system of the second embodiment of the utility model. DETAILED DESCRIPTION

[0022] The specific implementation of the present invention is described below with reference to the accompanying drawings. In order to fully understand the present invention, many details are described below, but for those skilled in the art, the present invention can be implemented without these details. For well-known components, methods and processes, they are not described in detail below.

[0023] Embodiment 1

[0024] This embodiment provides a fuel cell humidifier, referring to Figure 2 and Figure 3, including a humidifier main body 10, with a dry gas inlet 101 and a dry gas outlet 102 respectively provided at the front and rear ends of the humidifier main body 10. Two partitions 11 are spaced inside the humidifier main body to divide the humidifier main body 10 into an exchange chamber 12.

[0025] Refer to Figure 2 and Figure 3 , a number of hydrophilic hollow fiber tubes 13 are arranged in parallel in the exchange chamber 12. Through holes 110 are provided on the partitions 11 at both ends of each hollow fiber tube 13, corresponding to and communicating with the dry gas inlet 101 and the dry gas outlet 102 respectively. A wet gas inlet 103 and a wet gas outlet 104 are provided on the side of the exchange chamber 12 in communication. Hot air enters from the dry gas inlet 101, and wet air enters the exchange chamber 12 from the wet gas inlet 103. The water vapor in the wet air diffuses into the hollow fiber tube 13 due to concentration difference to realize humidification of the hot air; finally, the hot air is discharged from the dry gas outlet 102 and enters the fuel cell stack.

[0026] Refer to Figure 2 and Figure 3 , a spray port 105 communicating with it is provided on the top surface of the exchange chamber 12. Liquid water is sprayed onto the hollow fiber tubes 13 in the exchange chamber 12 through the spray port 105. The liquid water sprayed from above the humidifier is more likely to be adsorbed on the hydrophilic membrane tube and penetrate into the hollow fiber tube 13. When the hot air compressed by the air compressor passes through, the liquid water will vaporize to realize secondary humidification of the dry air.

[0027] Refer to Figure 2 and Figure 3 , two spray ports 105 are shown in this embodiment. Of course, in other embodiments, the spray port 105 can also be one, three or more than three.

[0028] Refer to Figure 3 , since the leakage of the wet side air should be as small as possible when the wet air humidifies the humidifier and the humidifier has a drainage requirement, a drain port 106 is provided at the bottom of the exchange chamber 12, and a drain valve (not shown in the figure) is provided at the drain port 106. The drain valve is selected as an electromagnetic valve. The electromagnetic valve is controlled by the PWM method. The specific method is: if the current density is I, I ≤ 1 A / cm 2 , the duty ratio of the electromagnetic valve is 1 / 10; 1 A / cm 2 <I ≤ 1.5 A / cm 2 , the duty ratio of the electromagnetic valve is 2 / 10; 1.5 A / cm 2 <I ≤ 2 A / cm 2 , the duty ratio of the electromagnetic valve is 3 / 10; 2 A / cm 2 <I ≤ 2.5 A / cm 2 , the duty ratio of the electromagnetic valve is 4 / 10; 2.5 A / cm 2<I, the duty cycle of the solenoid valve is 5 / 10, and it can be calibrated and adjusted according to the actual test results.

[0029] Embodiment 2

[0030] This embodiment provides an air humidification system. Refer to Figure 4 , which includes the humidifier 1 in Embodiment 1, and also includes a water separator 2 and a rubber hose 3. The water separator 2 is provided with a water separator inlet 21, a water separator outlet 22 and a water outlet. The water separator inlet 21 is connected to the wet gas outlet 104, the water separator outlet 22 is connected to the inlet of the air compressor turbine end, and the water outlet is connected to the spray port 105 through the rubber hose 3.

[0031] Refer to Figure 4 , the water separator 2 is arranged above the humidifier 1 to ensure that the water separated by the water separator 2 can be sprayed onto the upper part of the hollow fiber tube inside the humidifier 1 through the rubber hose 3 by gravity.

[0032] Refer to Figure 4 , since the top surface of the humidifier 1 shown in this embodiment is provided with two spray ports 105, the rubber hose 3 correspondingly adopts a Y-shaped structure. The main pipeline at the top of the Y-shaped rubber hose is connected to the water outlet of the water separator 2, and the two branched pipelines at the bottom of the Y-shaped rubber hose are respectively connected to the two spray ports 105. A metal filter screen can be placed in the rubber hose 3 to play a role in filtering impurities and optimizing the spray effect.

[0033] The air humidification system composed of the water separator and the humidifier can realize secondary humidification of the air. And if the output power of the fuel cell system is higher, the current density is greater, the required air flow and pressure are also greater. At this time, the temperature of the air compressed by the air compressor is also higher, and the vaporization amount of the liquid water vapor will also increase accordingly. Therefore, the higher the power, the better the secondary humidification effect, which can effectively improve the problem of low humidification efficiency under high-power output conditions.

[0034] The above is only the specific embodiment of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantive modification made to the present invention using this concept shall fall within the scope of infringement of the protection scope of the present invention.

Claims

1. A fuel cell humidifier, comprising a humidifier body, wherein the front and rear ends of the humidifier body are respectively provided with a dry gas inlet and a dry gas outlet, wherein two partitions are arranged in the humidifier body between the dry gas inlet and the dry gas outlet, so that the humidifier body forms an exchange chamber, wherein a plurality of hydrophilic hollow fiber tubes are arranged in parallel in the exchange chamber, wherein the partitions at both ends of each hollow fiber tube are provided with through holes, which are respectively connected to the dry gas inlet and the dry gas outlet; and the sides of the exchange chamber are connected with a wet gas inlet and a wet gas outlet, wherein: The top surface of the exchange chamber is provided with a spray port communicated therewith, and the exchange chamber is also provided with a drain port, and a drain valve is installed at the drain port.

2. A fuel cell humidifier as claimed in claim 1, characterized in that: The top surface of the exchange chamber is provided with one, two, three or four spray openings.

3. A fuel cell humidifier as claimed in claim 1, characterized in that: The drain port is arranged at the bottom of the exchange chamber.

4. A fuel cell humidifier as claimed in claim 1, characterized in that: The drain valve is a solenoid valve.

5. An air humidification system, characterized in that: It includes the humidifier as described in claim 1, and also includes a water separator and a hose, the water separator is arranged above the humidifier, the water separator is provided with a water separator inlet, a water separator outlet and a water outlet, the water separator inlet is connected to the humidifier moisture outlet, the water separator outlet is connected to the air compressor turbine end inlet, and the water outlet is connected to the spray port through the hose.

6. An air humidification system as claimed in claim 5, characterized in that: The top surface of the exchange chamber is provided with two spray ports, and the rubber hose is Y-shaped.

7. An air humidification system as claimed in claim 5, characterized in that: A metal filter screen is arranged inside the rubber hose.

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