Hydrogen energy power generation system

Abstract

According to the hydrogen energy power generation system, gaseous air generated by gasification of liquid air serves as an oxidizing agent of a fuel cell, hydrogen serves as fuel of the fuel cell, cold energy of the liquid gas is used for cold power generation, the hydrogen energy power generation system can be used as an energy storage type hydrogen energy power plant and can also serve as driving energy of a carrier, and the expected social and economic benefits are obvious.

Description

Technical Field

[0001] The invention relates to a hydrogen power generation system, in particular to a hydrogen power generation system using liquid air to supply oxygen. Background Art

[0002] my country formally proposed at the 75th United Nations General Assembly: strive to reach the peak of carbon dioxide emissions before 2030 and strive to achieve carbon neutrality before 2060. Under the background of carbon neutrality, building a new power system with new energy as the main body has become a global consensus, and energy storage will participate as a core link, which is an important guarantee for maintaining the stability of the power system.

[0003] Photovoltaic and wind power generation have the characteristics of randomness and intermittency, and electricity has the characteristics of real-time balance of supply and demand and difficulty in large-scale storage. The large-scale photovoltaic and wind power generation installed and connected to the grid will aggravate the dual volatility and uncertainty of the supply and demand sides of the power system, making it difficult to regulate the peak of the system, and bringing about a series of problems such as abandoned light and abandoned wind. Energy storage can smooth the instability of photovoltaic and wind power generation and achieve a dynamic balance of power supply and demand; in summer, the demand for electricity is strong, and the difference between peak and valley electricity prices continues to expand. The difference between peak and valley electricity prices in 17 provinces and regions exceeds 0.7 yuan / kWh. The economic benefits of industrial and commercial energy storage projects are prominent, and the economic benefits of peak-valley arbitrage are significantly improved. Energy storage methods can use batteries, compressed air or water electrolysis to produce hydrogen energy storage. The configuration of energy storage is indispensable in the future green power energy system, and the role of new energy storage in promoting the development and consumption of new energy and the safe and stable operation of power systems is gradually emerging.

[0004] A fuel cell is an energy conversion device that directly converts the chemical energy of a fuel (such as hydrogen) combined with an oxidant into electrical energy through an electrochemical reaction. It has the advantages of less pollution, low noise, high power density, fast load response, and high energy conversion efficiency. It is considered to be one of the most promising and potential clean energy technologies.

[0005] Conventional fuel cells use oxygen in the air as an oxidant, and pollutants in the air need to be processed when in use, such as using air filters. The following factors should be considered during design: intake properties (pollutant type, pollutant concentration, and air flow), filter element volume, adsorption capacity of filter element materials, and filter pressure drop, etc. Improvements to the fuel cell air supply subsystem deserve attention.

[0006] Traditional vehicles such as cars, diesel vehicles, airplanes and ships use oil and gas as fuel to drive engines or internal combustion engines to provide driving power. The fuel combustion process will inevitably produce thermal pollution and other pollutants, such as nitrogen oxides, sulfur oxides brought into the fuel and produced during the combustion process, dioxins, etc., which will cause harm to people and the environment.

[0007] As a representative of "new energy" vehicles, pure electric vehicles have a strong development momentum and are driven by policies to replace gasoline and gas vehicles. However, pure electric vehicles currently have certain problems, such as fire accidents caused by their battery modules, which are difficult to rescue and cause great harm.

[0008] Therefore, it is worth exploring in depth the use of photovoltaic, wind power or valley electricity to produce hydrogen, produce liquid air and store energy, and then combine hydrogen fuel cells for energy storage and power generation. Summary of the invention

[0009] The purpose of the present invention is to solve the above problems and provide a hydrogen power generation system, which can be used to build a storage-type hydrogen power plant and can also be used as a new energy source for carriers to provide driving power for automobiles, diesel vehicles, ships or aircraft.

[0010] A hydrogen power generation system, the implementation process of which is as follows: The liquid air in the liquid air storage tank 3 enters the low-boiling-point working medium condenser 8, releases cold energy in the low-boiling-point working medium condenser 8, liquefies the gaseous low-boiling-point working medium 15 discharged from the low-boiling-point working medium expander 13, and then is gasified by the low-boiling-point working medium circulation pump 9 and the low-boiling-point working medium evaporator 10. The formed gaseous working medium enters the low-boiling-point working medium expander 13 to expand and do work, and drives the low-boiling-point working medium generator 14 to generate electricity. The gaseous low-boiling-point working medium 15 discharged from the low-boiling-point working medium expander 13 enters the low-boiling-point working medium condenser 8 again to absorb cold energy and liquefy, thereby forming a low-boiling-point working medium Rankine cycle loop. The gaseous air 16 coming out of the low-boiling-point working medium condenser 8 is used as the output gas 20, and enters the fuel cell 25 for electrochemical reaction with the gaseous hydrogen 28 coming out of the hydrogen storage 26 to generate direct current, which is transmitted to the battery 29 or the driver 30 via DC / AC or DC / DC.

[0011] The low-boiling-point working fluid generator 14 is an AC generator or a DC generator, which is converted into electric energy output matching the lower stage via AC / AC, DC / DC, DC / AC or AC / DC.

[0012] A recooler 7 is provided: the liquid air in the liquid air storage tank 3 enters the low-boiling-point working medium condenser 8 through the recooler 7, and the gaseous air 16 coming out of the low-boiling-point working medium condenser 8 is divided into two paths: one path is the output gas 20, which is transported to the fuel cell 25, and the other path is the gaseous reflux gas 17. The gaseous reflux gas 17 is liquefied by the compressor 18 and the recooler 7 to become the liquid reflux gas 19 which is transported to the liquid air storage tank 3.

[0013] The low boiling point working fluid expander 13 is a scroll type, screw type, centrifugal type, turbine type or piston type expander.

[0014] The recooler 7 recovers high-quality cold energy of the liquid air output from the liquid air storage tank 3 and transmits it to the reflux gas 17 pressurized by the compressor 18. The gaseous reflux gas 17 is liquefied in the recooler 7 and then transported to the liquid air storage tank 3.

[0015] The low-boiling-point working fluid in the low-boiling-point working fluid Rankine cycle loop has a boiling point of less than -10°C under standard atmospheric pressure, such as CN2013100293794-Steam Rankine-Low-Boiling-Point Working Fluid Rankine Combined Cycle Power Generation Device, CN2013100293775-Extraction Type Steam Rankine-Low-Boiling-Point Working Fluid Rankine Combined Cycle Power Generation Device, etc., which provide further descriptions of low-boiling-point working fluids. In the application, propane is used as the working fluid of the low-boiling-point working fluid Rankine cycle loop.

[0016] The heating medium of the low-boiling-point working medium evaporator 10 is a heat medium 11, which can be selected from air, water or seawater at room temperature. The liquid low-boiling-point working medium is heated in the low-boiling-point working medium evaporator 10 to be vaporized. The refrigerant 12 with reduced temperature coming out of the low-boiling-point working medium evaporator 10 can be used as a cold source to supply cold to cold units such as cold storage, refrigeration air conditioners or other cold users.

[0017] A vaporizer 4 is provided: one end of the vaporizer 4 is connected to the bottom liquid side of the liquid air storage tank 3 through a pipeline, and the other end is connected to the top gas side of the liquid air storage tank 3 through a pipeline; when the liquid air stored in the liquid air storage tank 3 releases energy, the pressure in the liquid air storage tank 3 decreases, and the liquid gas in the vaporizer 4 is heated to be vaporized and enter the top gas space of the liquid air storage tank 3, thereby maintaining the pressure in the liquid air storage tank 3 stable.

[0018] The heater in the gasifier 4 is made of metal coils or finned tubes, etc. The heating medium is preferably air, and the heating medium should contain less water to avoid ice clogging of the heater due to improper operation.

[0019] A pressure regulating pump 6 is provided: when the liquid air stored in the liquid air storage tank 3 releases energy, the pressure in the liquid air storage tank 3 decreases, and the output pressure is adjusted by the pressure regulating pump 6 to maintain the pressure of the delivered liquid air stable. The pressure regulating pump 6 adopts a variable frequency speed regulation operation mode to maintain the stability of the output pressure.

[0020] A pressure relief valve 6 is provided to regulate the pressure increase caused by the heat absorption of the liquid air in the liquid air storage tank 3 when the equipment is shut down, so as to prevent overpressure.

[0021] The output gas 20 is lower than the ambient temperature and can be used as a cold source to supply cold to the external cold unit.

[0022] A fuel cell water thermal management subsystem 31 is provided: the output gas 20 enters the fuel cell 25 through the fuel cell water thermal subsystem 31, and the cold energy of the output gas 20 generated by gasification of liquid air is used as a cold source of the fuel cell water thermal subsystem.

[0023] A humidifier 32 is provided: the output gas 20 enters the fuel cell 25 through the fuel cell hydrothermal subsystem 31 and the humidifier 32 .

[0024] A gas-water separator 33 is provided: hydrogen coming out of the fuel cell is separated into liquid water 34 through the gas-water separator 33 , and the gaseous hydrogen separated from the gas-water separator 33 is returned to the fuel cell 25 through the hydrogen compressor 36 .

[0025] The electric energy generated by the low-boiling-point working fluid generator 14 is transmitted to the battery 29 or the driver 30 via the DC / AC or AC / DC inverter 21 .

[0026] The electric energy generated by the fuel cell 25 is transmitted to the battery 29 or the driver 30 via DC / DC or DC / AC.

[0027] A controller 38 is provided: the electric energy of the DC / AC or AC / DC inverter 21 and the DC / DC converter 22 is used to control the air regulating valve 23 and the hydrogen regulating valve 27 via the controller 38, so that the reaction ratio of the gaseous air 24 and the gaseous hydrogen 28 entering the fuel cell 25 is appropriate.

[0028] The gaseous air 24 passes through the fuel cell 25 to form the cathode tail gas 37 and is discharged, and the gaseous hydrogen 28 passes through the fuel cell 25 to form the anode tail gas 35 and is discharged.

[0029] The hydrogen storage device 26 is a high-pressure gaseous hydrogen storage tank, a low-temperature liquid hydrogen storage tank, a process production hydrogen buffer tank or a solid metal hydride hydrogen storage tank.

[0030] The hydrogen in the hydrogen storage 26 is reduced in pressure or its cold energy is recovered to form gaseous hydrogen 28 which enters the fuel cell 25 .

[0031] For the terminology of the fuel cell part in this hydrogen power generation system, please refer to Chapter 4 Automotive Fuel Cell System P60-P99 of "Automotive Fuel Cell Technology" edited by Lin Rui (ISBN978-7-03-064994-2, Science Press, 2021.2, Beijing).

[0032] Equipment, pipelines, instruments, valves, cold preservation, bypass facilities with regulating functions, etc. not described in the present invention are matched with reference to or in accordance with mature technologies in well-known traditional processes.

[0033] The equipment and pipelines in the present invention adopt necessary heat recovery, cooling recovery, quality recovery and other measures.

[0034] Parts not mentioned in the present invention, such as safety accessories, automatic control, etc., are matched with existing well-known technologies, that is, existing mature, reliable and reasonable technical measures are applied to this system.

[0035] Compared with the prior art, the present invention has the following advantages: 1. Compared with the prior art, the present invention uses gaseous air generated by gasification of liquid air as the oxidant of hydrogen fuel cell. m H n 、NO x , SO2 and H2S, etc.) have been removed in the process of preparing liquid air, thus eliminating the impact of harmful gases in the air on the performance of the fuel cell, which is beneficial to the long-term and stable operation of the fuel cell; 2. Compared with the existing technology, the present invention can be used as a composite system of energy storage type cold power generation combined with fuel cell power generation, which can effectively absorb photovoltaic power, wind power or "shift valley to fill peak". The raw materials are extremely abundant ambient air and produced hydrogen, which is clean and environmentally friendly, and can achieve cogeneration of cold, electricity and heat; 3. Compared with the prior art, the present invention can provide driving power for vehicles such as cars, ships, aircraft, etc., and has strong endurance; 4. The hydrogen power generation system of the present invention can be conveniently used as a distributed power supply station for people in wartime. As long as there is liquid air and hydrogen transported, or even as long as there is liquid air, the backup power supply can be used to start the generator set to supply electricity, cooling and heating, and can provide high-quality air resources for breathing space in air defense facilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a process flow diagram of a hydrogen power generation system.

[0037] Figure 1Middle: 3-liquid air storage tank, 4-vaporizer, 5-pressure relief valve, 6-pressure regulating pump, 7-recooler, 8-low boiling point working fluid condenser, 9-low boiling point working fluid circulation pump, 10-low boiling point working fluid evaporator, 11-heat medium, 12-refrigerant (can be used as cooling medium), 13-low boiling point working fluid expander, 14-low boiling point working fluid generator, 15-gaseous low boiling point working fluid, 16-gaseous air, 17-return gas, 18-compressor, 19-liquid return gas, 20-output gas, 21-DC / AC or AC / DC inverter (DC is Direct current, AC is alternating current), 22-DC / DC converter (DC is direct current), 23-air control valve, 24-gaseous air, 25-fuel cell, 26-hydrogen storage, 27-hydrogen control valve, 28-gaseous hydrogen, 29-battery, 30-driver (such as motor, compressor, pump, power transmission and distribution equipment, etc.), 31-fuel cell water and heat management subsystem, 32-humidifier, 33-gas-water separator, 34-liquid water, 35-anode exhaust gas, 36-hydrogen compressor, 37-cathode exhaust gas, 38-controller. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0039] Embodiment 1: like Figure 1 As shown, a hydrogen power generation system, the implementation process is as follows: A hydrogen power generation system, the implementation process of which is as follows: The liquid air in the liquid air storage tank 3 enters the low-boiling-point working medium condenser 8 through the recooler 7, releases cold energy in the low-boiling-point working medium condenser 8, liquefies the gaseous low-boiling-point working medium 15 discharged from the low-boiling-point working medium expander 13, and then is gasified by the low-boiling-point working medium circulation pump 9 and the low-boiling-point working medium evaporator 10. The formed gaseous working medium enters the low-boiling-point working medium expander 13 to expand and do work, driving the low-boiling-point working medium generator 14 to generate electricity. The gaseous low-boiling-point working medium 15 discharged from the low-boiling-point working medium expander 13 enters the low-boiling-point working medium condenser 8 again to absorb cold energy and liquefy, thereby A low-boiling-point working medium Rankine cycle loop is formed, and the gaseous air 16 coming out of the low-boiling-point working medium condenser 8 is divided into two paths: one path is the output gas 20, which is transported to the fuel cell 25, and enters the fuel cell 25 for electrochemical reaction with the gaseous hydrogen 28 coming out of the hydrogen storage 26 to generate direct current, which is transported to the battery 29 or the driver 30 via DC / AC or DC / DC; the other path is the gaseous reflux gas 17, which is liquefied by the compressor 18 and the recooler 7 to become the liquid reflux gas 19 and transported to the liquid air storage tank 3.

[0040] The low-boiling-point working fluid generator 14 is an AC generator or a DC generator, which is converted into electric energy output matching the lower stage via AC / AC, DC / DC, DC / AC or AC / DC.

[0041] The low boiling point working fluid expander 13 is a scroll type, screw type, centrifugal type, turbine type or piston type expander.

[0042] The recooler 7 recovers high-quality cold energy of the liquid air output from the liquid air storage tank 3 and transmits it to the reflux gas 17 pressurized by the compressor 18. The gaseous reflux gas 17 is liquefied in the recooler 7 and then transported to the liquid air storage tank 3.

[0043] The low boiling point working fluid in the low boiling point working fluid Rankine cycle loop is propane.

[0044] The heating medium of the low-boiling-point working medium evaporator 10 is a heat medium 11, which can be selected from air, water or seawater at room temperature. The liquid low-boiling-point working medium is heated in the low-boiling-point working medium evaporator 10 to be vaporized. The refrigerant 12 with reduced temperature coming out of the low-boiling-point working medium evaporator 10 can be used as a cold source to supply cold to cold units such as cold storage, refrigeration air conditioners or other cold users.

[0045] A vaporizer 4 is provided: one end of the vaporizer 4 is connected to the bottom liquid side of the liquid air storage tank 3 through a pipeline, and the other end is connected to the top gas side of the liquid air storage tank 3 through a pipeline; when the liquid air stored in the liquid air storage tank 3 releases energy, the pressure in the liquid air storage tank 3 decreases, and the liquid gas in the vaporizer 4 is heated to be vaporized and enter the top gas space of the liquid air storage tank 3, thereby maintaining the pressure in the liquid air storage tank 3 stable.

[0046] The heater in the gasifier 4 is made of metal coils or finned tubes, etc. The heating medium is preferably air, and the heating medium should contain less water to avoid ice clogging of the heater due to improper operation.

[0047] A pressure regulating pump 6 is provided: when the liquid air stored in the liquid air storage tank 3 releases energy, the pressure in the liquid air storage tank 3 decreases, and the output pressure is adjusted by the pressure regulating pump 6 to maintain the pressure of the delivered liquid air stable. The pressure regulating pump 6 adopts a variable frequency speed regulation operation mode to maintain the stability of the output pressure.

[0048] A pressure relief valve 6 is provided to regulate the pressure increase caused by the heat absorption of the liquid air in the liquid air storage tank 3 when the equipment is shut down, so as to prevent overpressure.

[0049] The output gas 20 is lower than the ambient temperature and can be used as a cold source to supply cold to the external cold unit.

[0050] A fuel cell water thermal management subsystem 31 is provided: the output gas 20 enters the fuel cell 25 through the fuel cell water thermal subsystem 31, and the cold energy of the output gas 20 generated by gasification of liquid air is used as a cold source of the fuel cell water thermal subsystem.

[0051] A humidifier 32 is provided: the output gas 20 enters the fuel cell 25 through the fuel cell hydrothermal subsystem 31 and the humidifier 32 .

[0052] A gas-water separator 33 is provided: hydrogen coming out of the fuel cell is separated into liquid water 34 through the gas-water separator 33 , and the gaseous hydrogen separated from the gas-water separator 33 is returned to the fuel cell 25 through the hydrogen compressor 36 .

[0053] The electric energy generated by the low-boiling-point working fluid generator 14 is transmitted to the battery 29 or the driver 30 via the DC / AC or AC / DC inverter 21 .

[0054] The electric energy generated by the fuel cell 25 is transmitted to the battery 29 or the driver 30 via DC / DC or DC / AC.

[0055] A controller 38 is provided: the electric energy of the DC / AC or AC / DC inverter 21 and the DC / DC converter 22 is used to control the air regulating valve 23 and the hydrogen regulating valve 27 via the controller 38, so that the reaction ratio of the gaseous air 24 and the gaseous hydrogen 28 entering the fuel cell 25 is appropriate.

[0056] The gaseous air 24 passes through the fuel cell 25 to form the cathode tail gas 37 and is discharged, and the gaseous hydrogen 28 passes through the fuel cell 25 to form the anode tail gas 35 and is discharged.

[0057] The hydrogen storage device 26 is a high-pressure gaseous hydrogen storage tank, a low-temperature liquid hydrogen storage tank, a process production hydrogen buffer tank or a solid metal hydride hydrogen storage tank.

[0058] The hydrogen in the hydrogen storage 26 is reduced in pressure or its cold energy is recovered to form gaseous hydrogen 28 which enters the fuel cell 25 .

[0059] Equipment, pipelines, instruments, valves, cold preservation, bypass facilities with regulating functions, etc. not described in the present invention are matched with reference to or in accordance with mature technologies in well-known traditional processes.

[0060] The equipment and pipelines in the present invention adopt necessary heat recovery, cooling recovery, quality recovery and other measures.

[0061] Although the present invention has been disclosed as above with preferred embodiments, they are not intended to limit the present invention. Anyone familiar with the art can make various changes or modifications without departing from the spirit and scope of the present invention, which also belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the definition of the claims of this application.

Claims

1. A hydrogen power generation system, characterized in that: Liquid air in the liquid air storage tank (3) enters the low-boiling-point working medium condenser (8), and the gaseous low-boiling-point working medium (15) discharged from the low-boiling-point working medium expander (13) is liquefied in the low-boiling-point working medium condenser (8), and then gasified by the low-boiling-point working medium circulation pump (9) and the low-boiling-point working medium evaporator (10). The formed gaseous working medium enters the low-boiling-point working medium expander (13) to expand and perform work, driving the generator (14) to generate electricity. The gaseous low-boiling-point working medium (15) discharged from the low-boiling-point working medium expander (13) enters the low-boiling-point working medium condenser (8) again, thereby forming a low-boiling-point working medium Rankine cycle loop. The gaseous air (16) discharged from the low-boiling-point working medium condenser (8) is used as the output gas (20), and enters the fuel cell (25) to undergo an electrochemical reaction with the gaseous hydrogen (28) discharged from the hydrogen storage (26), thereby generating direct current.

2. The hydrogen power generation system according to claim 1, characterized in that: A recooler (7) is provided: the liquid air in the liquid air storage tank (3) enters the low-boiling-point working medium condenser (8) through the recooler (7); the gaseous air (16) coming out of the low-boiling-point working medium condenser (8) is divided into two paths: one path is output gas (20) which is transported to the fuel cell (25); the other path is gaseous return gas (17); the gaseous return gas (17) is liquefied through the compressor (18) and the recooler (7) to become liquid return gas (19) which is transported to the liquid air storage tank (3).

3. The hydrogen power generation system according to claim 1, characterized in that: A vaporizer (4) is provided: one end of the vaporizer (4) is connected to the bottom liquid side of the liquid air storage tank (3) through a pipeline, and the other end is connected to the top gas side of the liquid air storage tank (3) through a pipeline; when the liquid gas stored in the liquid air storage tank (3) releases energy, the pressure in the liquid air storage tank (3) decreases, and the liquid gas in the vaporizer (4) is heated to vaporize and enter the top gas space of the liquid air storage tank (3), thereby maintaining the pressure in the liquid air storage tank (3) stable.

4. The cold power generation system according to claim 1, characterized in that: A pressure regulating pump (6) is provided: when the liquid air stored in the liquid air storage tank (3) releases energy, the pressure in the liquid air storage tank (3) decreases, and the output pressure is adjusted by the pressure regulating pump (6) to maintain the pressure of the delivered liquid air stable.

5. The hydrogen power generation system according to claim 1, characterized in that: The refrigerant (12) with reduced temperature coming out of the low-boiling-point working fluid evaporator (10) is used as a cold source to supply cold air to the cold unit.

6. The hydrogen power generation system according to claim 1, characterized in that: The output gas (20) is used as a cold source to supply cold to a cold unit.

7. The hydrogen power generation system according to claim 1, characterized in that: A fuel cell water heat management subsystem (31) is provided: the output gas (20) enters the fuel cell (25) through the fuel cell water heat management subsystem (31).

8. The hydrogen power generation system according to claim 7, characterized in that: A humidifier (32) is provided: the output gas (20) enters the fuel cell (25) through the fuel cell hydrothermal subsystem (31) and the humidifier (32).

9. The hydrogen power generation system according to claim 1, characterized in that: The low boiling point working fluid generator (14) is an AC generator or a DC generator.

10. The hydrogen power generation system according to claim 1, characterized in that: The low boiling point working fluid expander (13) is a scroll type, screw type, centrifugal type, turbine type or piston type expander.

Images