High-temperature pemfc normal pressure low-speed waste heat steam power generation system and working method

Abstract

The application provides a high-temperature PEMFC normal-pressure low-speed waste heat water vapor power generation system and a working method, and belongs to the technical fields of fuel cell waste heat steam recovery, friction power generation and wet steam power generation. The power generation system comprises a gradient-pore sandwich structure power generation module arranged in a temperature and humidity control box, an external water vapor conveying pipeline and a non-contact heating pipeline, a high-temperature PEMFC module and a condensation module connected to the temperature and humidity control box through a gas conveying pipeline. The gradient-pore sandwich structure power generation module comprises, from bottom to top, a ceramic pore channel, a first metal porous anode, an aerogel layer, a metal porous cathode, a porous insulating layer, a second metal porous anode, a hydrogel layer and a porous inert electrode. By combining the gradient-pore sandwich structure power generation module, the high-temperature PEMFC module and the condensation module, the application can stably generate power by using low-speed normal-pressure waste heat water vapor without additional energy input.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of fuel cell waste heat steam recovery, friction power generation and humidity power generation, and in particular relates to a high-temperature PEMFC normal-pressure low-speed waste heat steam power generation system and a working method thereof, in particular to a gradient-pore sandwich structure power generation system based on direct utilization of high-temperature PEMFC normal-pressure low-speed waste heat steam and a working method thereof. BACKGROUND

[0002] In industrial production and living scenes, the generated water vapor contains heat and water components, which has very high recycling value. However, the high pressure and high temperature requirements of power generation methods such as turbines limit the recycling of normal-pressure water vapor. Current normal-pressure water vapor recycling technology usually relies on large energy-consuming facilities such as pressurizing equipment and gas storage tanks, and the additional large equipment investment and energy consumption increase the burden of energy conversion. Therefore, it is urgent to develop a simple, efficient and green energy utilization technology that can directly convert waste heat steam into electrical energy.

[0003] High-temperature proton exchange membrane fuel cells (PEMFC, working temperature range of 120-200℃) will generate a large amount of waste heat steam at normal pressure (temperature range of 80-100℃) in the power generation process. This part of water vapor has low flow rate and low pressure, so it is difficult to be directly applied to traditional power generation mode. Usually, it needs to go through heat exchange, steam re-compression, gas nozzle speed-up and other links to indirectly drive turbine equipment to realize power generation, which has problems such as complex equipment structure and low energy utilization efficiency.

[0004] Friction power generation technology and humidity power generation technology can directly generate electricity by using the heat energy and water content of water vapor, but this technology is highly dependent on the pore structure of the material and the humidity gradient. In order to improve the power generation efficiency and long-term use performance, it is necessary to flexibly desorb the adsorbed water to reset the humidity gradient, coordinate the adaptability of the water vapor temperature and the humidity power generation device working temperature range, and optimize the integrated way of waste heat steam delivery to the gradient-pore sandwich structure power generation module, avoiding problems such as damage to the structure of the humidity power generation device, uneven gas flow distribution, and condensate accumulation blocking the pore.

[0005] At present, the related prior art has:

[0006] The existing patent application with the publication number CN102705023A discloses a low-temperature steam power generation system, which comprises a turbine, a generator, a liquid evaporator, and a gas cooler. The liquid evaporator is in an environment at a first temperature and is used to convert liquid medium into steam medium. The steam medium is sprayed onto turbine blades through a gas nozzle to drive the turbine to generate electricity. The steam medium passing through the turbine enters the gas cooler, which is in an environment at a second temperature, thereby liquefying the steam medium into liquid medium. The liquid medium enters the liquid evaporator through a pipeline. The steam power generator system further comprises a vacuum system, which makes the liquid evaporator, turbine, and gas cooler in a vacuum-sealed low-pressure environment, so that the liquid medium generates steam at a temperature lower than the normal boiling point. The first temperature is higher than the normal temperature, and the second temperature is equal to or lower than the normal temperature. The system reduces the steam pressure through the vacuum system and drives the turbine to generate electricity by spraying steam onto the turbine blades through the gas nozzle. The utilization problem of low-temperature steam is solved, but the system still relies on turbine power generation, needs additional pressurizing and accelerating equipment, and still uses low-efficiency mechanical power generation, ignoring the conversion of chemical energy and electrical energy, and cannot avoid energy waste, structural complexity, and blade mechanical loss.

[0007] The existing patent document with the publication number CN111600511A discloses a preparation method of a water and humidity power generation device based on one-dimensional carboxylated carbon material. First, one-dimensional carboxylated carbon materials of different sizes are dispersed in a solvent to obtain a slurry. Then, the slurry of one-dimensional carboxylated carbon materials of different sizes is coated on a substrate from bottom to top, and the size of the one-dimensional carboxylated carbon materials increases step by step from bottom to top. After drying, a water and humidity power generation device based on one-dimensional carboxylated carbon materials is obtained. The method can spontaneously generate electrical energy by capillary action and humidity absorption. However, this patent only relies on weak and uncontrollable water evaporation to reduce the water content in the device to restore the water absorption capacity and humidity gradient, which cannot meet the long-term cyclic use requirements and has a time limit, and cannot flexibly switch between power generation and water extraction functions.

[0008] Therefore, there is an urgent need to develop a system that can directly convert low-speed normal-pressure waste heat steam into electrical energy without additional energy input, moving parts, and complex processes, which can avoid energy waste and be used flexibly for a long time. SUMMARY

[0009] In view of the defects in the prior art, the purpose of the present application is to provide a high-temperature PEMFC normal-pressure low-speed waste heat steam power generation system and working method.

[0010] The high-temperature PEMFC normal-pressure low-speed waste heat water vapor power generation system comprises a high-temperature PEMFC module, a non-contact heating pipeline, a water vapor delivery pipeline, a gradient-pore sandwich structure power generation module, a condensation module, a power storage module, a temperature and humidity control box, a transmission circuit and a gas delivery pipeline.

[0011] The gradient-pore sandwich structure power generation module is arranged inside the temperature and humidity control box.

[0012] The water vapor delivery pipeline and the non-contact heating pipeline are arranged outside the temperature and humidity control box.

[0013] The high-temperature PEMFC module is connected with the gas delivery pipeline, and the gas output from the high-temperature PEMFC module is branched to the non-contact heating pipeline and the water vapor delivery pipeline through a valve on the gas delivery pipeline.

[0014] One end of the water vapor delivery pipeline is connected with the gas delivery pipeline, and the other end of the water vapor delivery pipeline penetrates through a through hole at the bottom of the temperature and humidity control box and is connected with the gradient-pore sandwich structure power generation module.

[0015] The non-contact heating pipeline is arranged below the temperature and humidity control box and heats the gradient-pore sandwich structure power generation module.

[0016] The high-temperature PEMFC module and the gradient-pore sandwich structure power generation module are connected with the power storage module through the transmission circuit.

[0017] A plurality of air holes are arranged at a position higher than the side wall of the gradient-pore sandwich structure power generation module on the temperature and humidity control box, and one of the air holes is sealingly connected with the condensation module.

[0018] A plurality of gradient-pore sandwich structure power generation modules are arranged, and each gradient-pore sandwich structure power generation module comprises, from bottom to top, a ceramic pore channel, a first metal porous anode, an aerogel layer, a metal porous cathode, a porous insulating layer, a second metal porous anode, a hydrogel layer and a porous inert electrode which are sequentially and tightly connected.

[0019] Preferably, the pore sizes of the three layers of the ceramic pore channel, the aerogel layer and the hydrogel layer decrease in sequence, and the water absorption gradually increases.

[0020] Preferably, in the gradient-pore sandwich structure power generation module, the first metal porous anode and the metal porous cathode constitute an electrostatic induction electrode pair, and the aerogel layer is arranged between the two.

[0021] The second metal porous anode and the porous inert electrode constitute a diffusion humidity electrode pair, and a hydrogel layer is arranged between the second metal porous anode and the porous inert electrode in a bonded manner; the gradient porous sandwich structure power generation module realizes diffusion humidity power generation through the second metal porous anode, the hydrogel layer and the porous inert electrode.

[0022] Preferably, a porous insulating layer is arranged in a bonded manner between the metal porous cathode and the second metal porous anode;

[0023] The hydrogel layer absorbs water in the waste heat vapor stream generated by the high-temperature PEMFC module and water in the aerogel layer, and forms a humidity gradient and a cation concentration gradient in the upward direction of the hydrogel layer.

[0024] Preferably, a plurality of the gradient porous sandwich structure power generation modules are arranged in an array, the gradient porous sandwich structure power generation modules in a single row are connected in series, and the gradient porous sandwich structure power generation modules between rows are connected in parallel;

[0025] The electrostatic induction electrode pair and the diffusion humidity electrode pair are respectively connected to a transmission circuit and a switch;

[0026] The first metal porous anode, the metal porous cathode, the second metal porous anode and the porous inert electrode are respectively connected to a power storage module through a transmission circuit.

[0027] Preferably, the first metal porous anode, the metal porous cathode and the second metal porous anode are all metal porous electrodes;

[0028] The material of the metal porous electrode is one of gold, nickel, aluminum, copper, silver and alloy materials;

[0029] The porous structure of the metal porous electrode is one or more of circular holes, square holes and polygonal holes;

[0030] The aerogel layer is an aerogel composite material, and the aerogel composite material is one or more of cellulose and its derivatives, metal organic frameworks, graphene and carbon nanotubes;

[0031] The hydrogel layer is a hydrogel composite material, and the hydrogel composite material is one or more of cellulose and its derivatives, metal organic frameworks, hygroscopic salt and crosslinking agent;

[0032] The material of the porous insulating layer is one of polyimide, polyvinylidene fluoride and polytetrafluoroethylene;

[0033] The material of the porous inert electrode is one of graphite and carbon-based materials.

[0034] Preferably, the high-temperature PEMFC-based atmospheric low-speed waste heat water vapor power generation system further comprises a water storage module and a condensate water delivery pipeline,

[0035] The condensing module comprises a first fin condenser and a second fin condenser.

[0036] One end of the first fin condenser is connected to the temperature and humidity control box through the air hole in the side wall of the temperature and humidity control box, and the other end of the first fin condenser is connected to the water storage module through the condensate water delivery pipeline.

[0037] One end of the second fin condenser is connected to the non-contact heating pipeline through the gas delivery pipeline, and the other end is connected to the water storage module through the condensate water delivery pipeline.

[0038] Preferably, all the holes in the wall of the temperature and humidity control box are sealed with the water vapor delivery pipeline, the first fin condenser, the gas delivery pipeline, and the transmission circuit pipeline passing through the holes.

[0039] The high-temperature PEMFC-based atmospheric low-speed waste heat water vapor power generation system and working method provided by the application comprises a power generation method and a humidity gradient resetting method.

[0040] The power generation method comprises:

[0041] Step SE1: the non-contact heating pipeline valve is closed, the water vapor delivery pipeline valve is opened, and the water vapor delivery pipeline valve opening degree is adjusted.

[0042] Step SE2: the water vapor at the outlet of the high-temperature PEMFC module is delivered to the gradient pore sandwich structure power generation module, uniformly dispersed through the ceramic pore, and sequentially fully contacted with the aerogel layer and the hydrogel layer, to form a loop through the electrostatic induction electrode pair and the diffusion humidity electrode pair in the gradient pore sandwich structure power generation module and the external circuit, to complete power generation.

[0043] Preferably, the humidity gradient resetting method comprises:

[0044] Step SW1: the non-contact heating pipeline valve is opened, and the water vapor delivery pipeline valve is closed.

[0045] Step SW2: the water vapor supply at the outlet of the high-temperature PEMFC module is suspended, and the gradient pore sandwich structure power generation module in the temperature and humidity control box is heated using the non-contact heating pipeline.

[0046] Step SW3: the water vapor condensed and desorbed in the temperature and humidity control box is condensed in the first fin condenser, the formed liquid water droplets are delivered to the water storage module through the condensate water delivery pipeline, and the humidity gradient resetting is completed.

[0047] Compared with the prior art, the application has the following beneficial effects:

[0048] 1、The application can make full use of the heat and water of low-speed normal-pressure waste heat steam of high-temperature PEMFC to generate electricity without additional energy input, moving parts and complex processes by introducing a specially-structured gradient-pore sandwich structure power generation module;

[0049] 2、The application can complete the discharge of water in the gradient-pore sandwich structure power generation module by resetting the humidity gradient, reset the humidity gradient and water absorption capacity of the gradient-pore sandwich structure power generation module, and collect the remaining water resources, which has recyclability and good energy conversion efficiency;

[0050] 3、The application adopts a multi-layer composite structure in the gradient-pore sandwich structure power generation module, which couples the gradient-pore structure, different material properties and power generation mechanism, is conducive to the uniform contact of waste heat steam and aerogel layer and hydrogel layer, reduces the influence of condensed water on the structure and performance of the gel, and maintains the humidity gradient, which has high stability and energy efficiency;

[0051] 4、The application adopts renewable cellulose as the basic material for the aerogel layer and the hydrogel layer, which has good degradability and environmental friendliness. BRIEF DESCRIPTION OF DRAWINGS

[0052] Other features, objects and advantages of the application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the accompanying drawings:

[0053] Figure 1 It is a high-temperature PEMFC normal-pressure low-speed waste heat steam power generation system and working method based on the application;

[0054] Figure 2 It is a structure diagram of the gradient-pore sandwich structure power generation module of the application.

[0055] The figure shows: high-temperature PEMFC module 1; power storage module 2; gradient-pore sandwich structure power generation module 3; first fin condenser 4; water storage module 5; second fin condenser 6; condensation module 7; non-contact heating pipeline 8; water vapor delivery pipeline 9; ceramic pore channel 10; first metal porous anode 11; aerogel layer 12; metal porous cathode 13; porous insulating layer 14; second metal porous anode 15; hydrogel layer 16; porous inert electrode 17; temperature and humidity control box 18. DETAILED DESCRIPTION

[0056] The application will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be pointed out that those skilled in the art can make several changes and improvements without departing from the concept of the application. These all belong to the protection scope of the application.

[0057] As shown in Figure 1 and Figure 2 The embodiment of the application provides a high-temperature PEMFC normal-pressure low-speed waste heat steam power generation system, specifically, a system for directly converting waste heat steam into electric energy by using low-speed normal-pressure water steam at the outlet of a high-temperature proton exchange membrane fuel cell (PEMFC) through a gradient-pore sandwich structure power generation module.

[0058] The high-temperature PEMFC normal-pressure low-speed waste heat steam power generation system provided by the embodiment of the application comprises a high-temperature PEMFC module 1, a non-contact heating pipeline 8, a water steam delivery pipeline 9, a gradient-pore sandwich structure power generation module 3, a condensation module 7, a water storage module 5, an electricity storage module 2, a temperature and humidity control box 18, a transmission circuit, a gas delivery pipeline and a condensate water delivery pipeline.

[0059] The high-temperature PEMFC module 1 and the gradient-pore sandwich structure power generation module 3 are connected with the electricity storage module 2 through the transmission circuit; the gradient-pore sandwich structure power generation module 3 is arranged in the temperature and humidity control box 18; the water steam delivery pipeline 9 and the non-contact heating pipeline 8 are arranged outside the temperature and humidity control box 18; specifically, one end of the water steam delivery pipeline 9 is connected with the main gas delivery pipeline, and the other end of the water steam delivery pipeline 9 penetrates through a tiny through hole at the bottom of the temperature and humidity control box 18 and is connected with the gradient-pore sandwich structure power generation module 3. More specifically, the tiny hole only allows the water steam delivery pipeline 9 connected with the gradient-pore sandwich structure power generation module 3 to pass through, and the gap between the pipeline and the tiny hole is sealed. The non-contact heating pipeline 8 is arranged in an S shape below the temperature and humidity control box 18 and heats the gradient-pore sandwich structure power generation module 3. The high-temperature PEMFC module 1 is connected with the main gas delivery pipeline of the power generation system, and the gas output from the high-temperature PEMFC module 1 is branched to the non-contact heating pipeline 8 and the water steam delivery pipeline 9 through a valve on the main gas delivery pipeline.

[0060] Further, a plurality of air holes are arranged on the upper part of the temperature and humidity control box 18 higher than the top side wall of the gradient-pore sandwich structure power generation module 3, one side of the air holes is connected with the condensation module 7, and the connection between the two needs to be sealed. Specifically, one side of the air holes is tightly connected with the condensation module 7.

[0061] Furthermore, the condensation module 7 includes a first finned condenser 4 and a second finned condenser 6. One end of the first finned condenser 4 is connected to the temperature and humidity control chamber 18 through a vent hole on the side wall of the temperature and humidity control chamber 18, and the other end of the first finned condenser 4 is connected to the water storage module 5 through a condensate delivery pipeline. One end of the second finned condenser 6 is connected to the non-contact heating pipe 8 through a gas delivery pipeline, and the other end is connected to the water storage module 5 through a condensate delivery pipeline. In a more specific embodiment, the water storage module 5 can be simplified to a water collection tank.

[0062] Multiple gradient pore sandwich structure power generation modules 3 are provided, and the multiple gradient pore sandwich structure power generation modules 3 are arranged in an array. Each gradient pore sandwich structure power generation module 3 is regarded as a wet gas generator, and the multiple gradient pore sandwich structure power generation modules 3 arranged in the array are integrated into a wet gas power generation group. Furthermore, the gradient pore sandwich structure power generation modules 3 in a single row are connected in series, and the gradient pore sandwich structure power generation modules 3 between rows are connected in parallel.

[0063] like Figure 2 The diagram shows a single gradient pore sandwich structure power generation module 3. The gradient pore sandwich structure power generation module 3 includes: two sets of electrodes and three material layers; the two sets of electrodes are: an electrostatic induction electrode pair and a diffusion humidity electrode pair; the three material layers include: ceramic channels 10, an aerogel layer 12 obtained by directional freezing, and a hydrogel layer 16.

[0064] The electrostatic induction electrode pair includes: a first porous metal anode 11 and a porous metal cathode 13; an aerogel layer 12 is tightly attached between the first porous metal anode 11 and the porous metal cathode 13 above it; the gradient pore sandwich structure power generation module 3 realizes electrostatic induction power generation through the first porous metal anode 11, the aerogel layer 12 and the porous metal cathode 13.

[0065] The diffusion humidity electrode pair includes a second porous metal anode 15 and an upper porous inert electrode 17. A hydrogel layer 16 is tightly bonded between the second porous metal anode 15 and the upper porous inert electrode 17. The gradient pore sandwich structure power generation module 3 achieves diffusion humidity power generation through the second porous metal anode 15, the hydrogel layer 16, and the porous inert electrode 17. The hydrogel layer 16 adsorbs water from the waste heat steam gas flow produced by the high-temperature PEMFC module 1 and water from the aerogel layer 12, forming a humidity gradient and a cation concentration gradient in the hydrogel layer 16 from bottom to top.

[0066] The metal porous negative electrode 13 of the electrostatic induction electrode pair and the second metal porous positive electrode 15 of the humidity electrode pair are tightly attached with the porous insulating layer 14. The ceramic pore channel 10 is arranged at the bottom of the entire gradient porous sandwich structure power generation module 3, and the ceramic pore channel 10 is attached with the first metal porous positive electrode 11.

[0067] Further, the two groups of electrodes are respectively connected with transmission circuits and switches; wherein the first metal porous positive electrode 11, the metal porous negative electrode 13, the second metal porous positive electrode 15 and the porous inert electrode 17 are respectively connected with the transmission circuits and connected with the power storage module 2. More specifically, the transmission circuit connected with the electrode pair is led out from the micro hole in the side wall of the temperature and humidity control box 18, and the micro hole only allows the transmission circuit wire connected with the electrode pair to pass through, and the gap between the wire and the micro hole is sealed.

[0068] More specifically, the first metal porous positive electrode 11, the metal porous negative electrode 13 and the second metal porous positive electrode 15 are all metal porous electrodes, and the material of the metal porous electrode is preferably one of gold, nickel, aluminum, copper, silver and alloy material, and the porous structure is one or more of circular holes, square holes and polygonal holes. The aerogel layer 12 is an aerogel composite material, and is preferably one or more of cellulose and its derivatives, metal organic framework, graphene and carbon nanotube. The hydrogel layer 16 is a hydrogel composite material, and is preferably one or more of cellulose and its derivatives, metal organic framework, hygroscopic salt and crosslinking agent. The material of the porous insulating layer 14 is preferably one of polyimide, polyvinylidene fluoride and polytetrafluoroethylene. The material of the porous inert electrode 17 is preferably one of graphite and carbon-based material.

[0069] The application also provides a power generation working method based on the high-temperature PEMFC normal-pressure low-speed waste heat water vapor power generation system provided by the application, comprising:

[0070] Step SE1: the valve of the non-contact heating pipeline 8 is closed, and the valve of the water vapor conveying pipeline 9 is opened; the opening degree of the valve of the water vapor conveying pipeline 9 can be adjusted according to the required steam flow for optimal power generation power;

[0071] Step SE2: the water vapor at the outlet of the high-temperature PEMFC module 1 is conveyed to the gradient porous sandwich structure power generation module 3, uniformly dispersed through the ceramic pore channel 10, and then fully contacted with the aerogel layer 12 and the hydrogel layer 16 in sequence, to form a loop through the electrode pair and the external circuit, and then the power generation function is completed.

[0072] In the above power generation method, the three-layer material of ceramic channel 10, aerogel layer 12 and hydrogel layer 16 has sequentially decreasing porosity and gradually increasing water absorption, which can not only reduce the risk of condensate water blocking pores, structure collapse, material damage and other risks caused by high humidity and high heat vapor directly contacting the aerogel layer and the hydrogel layer, but also effectively control the saturation speed of the water absorption material, fully exerting the power generation capacity of the material.

[0073] The gradient-porosity sandwich structure power generation module 3 couples the following two power generation mechanisms through the layered structure design:

[0074] Power generation mechanism A: static induction power generation is realized by the first metal porous anode 11, the aerogel layer 12 and the metal porous cathode 13:

[0075] The principle of static induction power generation between water vapor and the aerogel layer 12 is based on the unique porous structure of aerogel and the electrostatic induction effect of gas-solid interface. Energy conversion is achieved through charge transfer and separation caused by water vapor diffusion or flow in the aerogel. When high-temperature water vapor flows through the porous aerogel layer 12, the vapor molecules and the surface of the aerogel nanopores have charge transfer due to the difference in electron affinity (such as modified aerogel surface capturing electrons and being negatively charged, water molecules losing electrons and being positively charged). Subsequently, the flow of steam causes charge separation, forming a potential difference between the first metal porous anode 11 and the metal porous cathode 13 in close contact with the aerogel layer 12 on both sides of the structure. The high specific surface area and hierarchical pore structure of the aerogel significantly increase the contact sites, and the continuous steam flow or humidity gradient drive can maintain dynamic charge balance. Through the transmission circuit, the waste heat steam kinetic energy is directly converted into electrical energy transmission.

[0076] Power generation mechanism B: diffusion humidity power generation is realized by the second metal porous anode 15, the hydrogel layer 16 and the porous inert electrode 17;

[0077] The waste heat steam inputted from the high-temperature PEMFC module 1 diffuses from the ceramic pore channel 10, diffuses upward from the bottom to the top (from high humidity to low humidity) through the aerogel layer 12, and forms a humidity gradient and an ion concentration gradient from the bottom to the top of the hydrogel layer 16, so as to generate a diffusion potential and a current. The water in the steam is adsorbed by the hydrophilic functional groups (such as -OH, -COOH and -SO3H) in the strong hygroscopic hydrogel layer 16, and the difference in chemical potential can be used as an internal incentive to cause phase change of water molecules on the surface of the hydrogel layer 16, that is, the gaseous water is converted into liquid water, the oxygen-containing functional groups are dissociated, and then a cation gradient is formed and a diffusion process is driven (the cations move along the diffusion direction of the water), so as to realize electron migration through the transmission circuit to obtain electric power. For the hygroscopic gel composed of isotropic functional materials, when the water is adsorbed on the hygroscopic side of the hydrogel layer 16, the diffusion of protons is realized by the difference in water along the thickness direction of the hydrogel layer 16. In order to long-term maintain the humidity gradient to achieve a more ideal power generation effect, an asymmetric hygroscopic structure (for example, gradient distribution of the same functional groups, layered composite of different materials, etc.) can be introduced, and an additional ion concentration gradient is artificially introduced by adjusting the chemical composition; the diffusion direction of the aerogel layer 12 and the hydrogel layer 16 can also be constructed by directional freezing and the like, so as to accelerate the diffusion of protons and increase the potential difference.

[0078] The application also provides a humidity gradient resetting method based on the high-temperature PEMFC normal-pressure low-speed waste heat steam power generation system provided by the application, which can also be referred to as a water taking method or a power generation function resetting method, and the method comprises the following steps:

[0079] Step SW1: open the valve of the non-contact heating pipeline 8 and close the valve of the water vapor conveying pipeline 9.

[0080] Step SW2: suspend the water vapor supply at the outlet of the high-temperature PEMFC module 1 and heat the gradient pore sandwich structure power generation module 3 in the temperature and humidity regulation box 18 by using the non-contact heating pipeline 8; specifically, by suspending the humidity supply and heating from the bottom, the water adsorbed in the gradient pore sandwich structure power generation module 3 reaches the water desorption temperature, evaporates, restores the water absorption capacity of the gel and resets the humidity gradient, so that the gradient pore sandwich structure power generation module 3 can be recycled.

[0081] Step SW3: the condensed water vapor in the temperature and humidity regulation box 18 is condensed by the first fin condenser 4, and the formed liquid water droplets are conveyed to the water storage module 5 through the condensate conveying pipeline, so as to complete the humidity gradient resetting, and complete the water taking and power generation function resetting tasks.

[0082] In a variation of the application, the water in the gradient porous sandwich structure power generation module 3 can be further promoted by adding a fan or pressurizing outside the air hole of the temperature and humidity control box. The water in the gradient porous sandwich structure power generation module 3 is discharged by the combination of the non-contact heating pipeline 8 and the condensation module 7, which resets the humidity gradient and the water absorption capacity. The condensation module 7 of the system condenses the gas into water, and the liquid water flows to the water storage module 5. The system realizes self-sustaining operation of the moisture power generation and eliminates the time condition and other factors.

[0083] In summary, the embodiment of the application provides a high-temperature PEMFC normal-pressure low-speed waste heat steam power generation system and working method. The heat and moisture of the high-temperature PEMFC low-speed normal-pressure waste heat steam are fully transported by the non-contact heating pipeline 8, the gas delivery pipeline and the condensation module 7, and the water is discharged by the non-contact heating pipeline 8 and the condensation module 7, which resets the humidity gradient and the water absorption capacity. The system has recyclability and good energy conversion efficiency. Under the premise of no additional energy input, moving parts and complex processes, the low-speed normal-pressure waste heat steam is directly converted into electric energy by the gradient porous sandwich structure power generation module 3, which reduces energy waste and simplifies the system structure. Further, the gradient porous sandwich structure power generation module 3 adopts a multi-layer composite structure to couple the gradient porous structure, different material properties and power generation mechanism, which is beneficial to the uniform contact of the waste heat steam with the aerogel layer 12 and the hydrogel layer 16, reduces the influence of condensed water on the gel structure and performance, and maintains the humidity gradient, has high stability and energy efficiency. The above aerogel layer 12 and hydrogel layer 16 use renewable cellulose as the basic material, which has good degradability and environmental friendliness.

[0084] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0085] The specific embodiments of the application are described above. It should be understood that the application is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essential content of the application. The embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other without conflict.

Claims

1. A high temperature PEMFC based atmospheric pressure low speed waste heat steam power generation system, characterized in that, The application relates to a high-temperature PEMFC module (1), a non-contact heating pipeline (8), a water vapor delivery pipeline (9), a gradient-pore sandwich structure power generation module (3), a condensation module (7), an electricity storage module (2), a temperature and humidity control box (18), a transmission circuit and a gas delivery pipeline. The gradient-pore sandwich structure power generation module (3) is arranged inside the temperature and humidity control box (18). The water vapor delivery pipeline (9) and the non-contact heating pipeline (8) are arranged outside the temperature and humidity control box (18). The high-temperature PEMFC module (1) is connected with the gas delivery pipeline, and the gas output from the high-temperature PEMFC module (1) is branched to the non-contact heating pipeline (8) and the water vapor delivery pipeline (9) through valves on the gas delivery pipeline. One end of the water vapor delivery pipeline (9) is connected with the gas delivery pipeline, and the other end of the water vapor delivery pipeline (9) penetrates through a through hole in the bottom of the temperature and humidity control box (18) and is connected with the gradient-pore sandwich structure power generation module (3). The non-contact heating pipeline (8) is arranged below the temperature and humidity control box (18) and heats the gradient-pore sandwich structure power generation module (3). The high-temperature PEMFC module (1) and the gradient-pore sandwich structure power generation module (3) are connected with the electricity storage module (2) through the transmission circuit. Multiple air holes are arranged on the side wall of the temperature and humidity control box (18), and the height of the air holes is higher than that of the gradient-pore sandwich structure power generation module (3). The air holes on one side of the temperature and humidity control box (18) are sealingly connected with the condensation module (7). Multiple gradient-pore sandwich structure power generation modules (3) are arranged, and each gradient-pore sandwich structure power generation module (3) comprises, from bottom to top, a ceramic pore channel (10), a first metal porous anode (11), an aerogel layer (12), a metal porous cathode (13), a porous insulating layer (14), a second metal porous anode (15), a hydrogel layer (16) and a porous inert electrode (17) which are sequentially and tightly connected. The pore sizes of the three layers of the ceramic pore channel (10), the aerogel layer (12) and the hydrogel layer (16) gradually decrease, and the water absorption gradually increases. In the gradient-pore sandwich structure power generation module (3), 2. The high temperature PEMFC based atmospheric pressure low speed waste heat water vapor power generation system according to claim 1, characterized in that, The first metal porous anode (11) and the metal porous cathode (13) constitute an electrostatic induction electrode pair, and the aerogel layer (12) is arranged between the first metal porous anode (11) and the metal porous cathode (13); the gradient-pore sandwich structure power generation module (3) realizes electrostatic induction power generation through the first metal porous anode (11), the aerogel layer (12) and the metal porous cathode (13); The second metal porous anode (15) and the porous inert electrode (17) constitute a diffusion humidity electrode pair, the hydrogel layer (16) is arranged between the second metal porous anode (15) and the porous inert electrode (17), and the gradient-pore sandwich structure power generation module (3) realizes diffusion humidity power generation through the second metal porous anode (15), the hydrogel layer (16) and the porous inert electrode (17). ​ 3. The atmospheric low-speed waste heat steam power generation system based on high-temperature PEMFC according to claim 1, characterized in that, a porous insulating layer (14) is arranged between the metal porous cathode (13) and the second metal porous anode (15); the water in the waste heat steam flow generated by the high-temperature PEMFC module (1) and the water in the aerogel layer (12) are adsorbed by the hydrogel layer (16), and a humidity gradient and a cation concentration gradient are formed in the hydrogel layer (16) from bottom to top.

4. The atmospheric low-speed waste heat steam power generation system based on high-temperature PEMFC according to claim 2, characterized in that, a plurality of the gradient porous sandwich structure power generation modules (3) are arranged in an array, the gradient porous sandwich structure power generation modules (3) in a single row are connected in series, and the gradient porous sandwich structure power generation modules (3) between rows are connected in parallel; the electrostatic induction electrode pair and the diffusion humidity electrode pair are respectively connected to a transmission circuit and a switch; the first metal porous anode (11), the metal porous cathode (13), the second metal porous anode (15), and the porous inert electrode (17) are respectively connected to the electricity storage module (2) through the transmission circuit.

5. The atmospheric low-speed waste heat steam power generation system based on high-temperature PEMFC according to claim 1, characterized in that, the first metal porous anode (11), the metal porous cathode (13), and the second metal porous anode (15) are all metal porous electrodes; the material of the metal porous electrode is one of gold, nickel, aluminum, copper, silver, and alloy material; the porous structure of the metal porous electrode is one or more of circular holes, square holes, and polygonal holes; the aerogel layer (12) is an aerogel composite material, and the aerogel composite material is one or more of cellulose and its derivatives, metal organic frameworks, graphene, and carbon nanotubes; the hydrogel layer (16) is a hydrogel composite material, and the hydrogel composite material is one or more of cellulose and its derivatives, metal organic frameworks, hygroscopic salt, and crosslinking agent; the material of the porous insulating layer (14) is one of polyimide, polyvinylidene fluoride, and polytetrafluoroethylene; the material of the porous inert electrode (17) is one of graphite and carbon-based material.

6. The high temperature PEMFC based atmospheric pressure low speed waste heat water vapor power generation system of claim 1, wherein, Further comprising: a water storage module (5) and a condensate water delivery pipeline, the condensing module (7) comprises a first fin condenser (4) and a second fin condenser (6); one end of the first fin condenser (4) is connected to the temperature and humidity control box (18) through the air hole in the side wall of the temperature and humidity control box (18), and the other end of the first fin condenser (4) is connected to the water storage module (5) through the condensate water delivery pipeline; one end of the second fin condenser (6) is connected to the non-contact heating pipeline (8) through the gas delivery pipeline, and the other end is connected to the water storage module (5) through the condensate water delivery pipeline.

7. The atmospheric low-speed waste heat steam power generation system based on high-temperature PEMFC according to any one of claims 1 to 6, characterized in that, All holes in the wall of the temperature and humidity control box (18) are sealed with the water vapor delivery pipe (9), the first fin condenser (4), the gas delivery pipe and the transmission circuit.

8. A method of operating a high temperature PEMFC based atmospheric pressure low speed waste heat steam power generation system according to any one of claims 1 to 6, characterized in that, The application relates to a power generation method and a humidity gradient resetting method. The power generation method comprises the following steps: Step SE1: the valve of the non-contact heating pipe (8) is closed, and the valve of the water vapor delivery pipe (9) is opened; the opening degree of the valve of the water vapor delivery pipe (9) is adjusted; Step SE2: the water vapor at the outlet of the high-temperature PEMFC module (1) is delivered to the gradient porous sandwich structure power generation module (3), is uniformly dispersed through the ceramic pore channel (10) and then fully contacts the aerogel layer (12) and the hydrogel layer (16) in sequence, a loop is formed through the electrostatic induction electrode pair and the diffusion humidity electrode pair in the gradient porous sandwich structure power generation module (3) and an external circuit, and power generation is completed.

9. The working method of the high-temperature PEMFC atmospheric pressure low-speed waste heat water vapor power generation system according to claim 8, characterized in that, The humidity gradient resetting method comprises the following steps: Step SW1: the valve of the non-contact heating pipe (8) is opened, and the valve of the water vapor delivery pipe (9) is closed; Step SW2: the water vapor supply at the outlet of the high-temperature PEMFC module (1) is suspended, and the gradient porous sandwich structure power generation module (3) in the temperature and humidity control box (18) is heated by using the non-contact heating pipe (8); Step SW3: the water vapor condensed and desorbed in the temperature and humidity control box (18) is condensed in the first fin condenser (4), liquid water drops formed are delivered to the water storage module (5) through the condensed water delivery pipe, and the humidity gradient resetting is completed.

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