Distributed energy system of organic liquid hydrogen storage coupled oxygen-hydrogen-rich internal combustion engine and working method of distributed energy system

Abstract

The invention discloses a distributed energy system of an organic liquid hydrogen storage coupled oxygen-hydrogen-rich internal combustion engine and a working method of the distributed energy system. The system comprises the oxygen-hydrogen-rich internal combustion engine and an organic liquid hydrogen storage system. The oxygen-enriched combustion hydrogen internal combustion engine comprises a hydrogen inlet, an oxygen inlet, an air inlet and a waste gas outlet. The dehydrogenation heat absorption reaction heat of the organic liquid hydrogen storage system is from five ways, namely hydrogenation reaction heat release of the organic liquid hydrogen storage system, engine waste heat recovery, supercharged intercooling heat of an oxygen-hydrogen-rich internal combustion engine, hydrogen catalytic combustion heat compensation and electric heating assistance; during cold start of the internal combustion engine, an organic working medium system is assisted in hydrogen supply through electric heating, and after start, engine waste heat is recycled, cold heat in pressurization of the oxygen-hydrogen-enriched internal combustion engine is used for preheating, and hydrogen catalytic combustion is used for supplementing heat; when wind and light fluctuating energy exists, the wind and light energy water electrolysis hydrogen production system is started, generated hydrogen is converted into hydrogen-rich organic liquid working medium hydrogen storage through hydrogenation reaction, and heat is generated to assist dehydrogenation endothermic reaction.

Description

Technical Field

[0001] This invention relates to distributed energy generation systems, and particularly to a distributed energy system and its operating method that uses organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine. Background Technology

[0002] Renewable wind and solar energy are fluctuating energy sources, making stable power generation impossible. Converting renewable energy into hydrogen is an important way to achieve energy self-sufficiency and dual-carbon goals. However, high-pressure or liquefaction hydrogen storage is energy-intensive and unsuitable for large-scale hydrogen storage.

[0003] Organic liquid hydrogen storage (LOHC) is a method of reversibly storing hydrogen using liquid organic matter at ambient temperature and pressure. It avoids the explosion risk of high-pressure gaseous hydrogen storage and the extremely low temperature cost of liquid hydrogen. It has a high volumetric hydrogen storage density and can directly utilize existing petroleum storage and transportation facilities, which can significantly reduce the cost of upgrading hydrogen energy infrastructure. It is a way to solve the storage and transportation bottleneck of large-scale hydrogen energy applications.

[0004] Hydrogen energy is utilized in power generation. Hydrogen internal combustion engines have high thermal efficiency, can directly use low-purity hydrogen, can inherit traditional internal combustion engine components, have low modification costs, and are suitable for distributed power generation scenarios. This is one of the technical routes for the large-scale application of hydrogen energy.

[0005] Stable hydrogen power generation can be achieved by coupling organic liquid hydrogen storage with a hydrogen internal combustion engine, but the key challenges are how to design the system and how to achieve cascade utilization of waste heat to improve the overall system efficiency. Summary of the Invention

[0006] To overcome the difficulties of the prior art, the present invention aims to provide a distributed energy system and its operating method that couples organic liquid hydrogen storage with an oxygen-enriched combustion hydrogen internal combustion engine. This system utilizes the oxygen-enriched combustion technology of the hydrogen internal combustion engine to improve combustion efficiency, increase power output, shorten combustion time, and reduce heat loss. Regarding waste heat utilization, five pathways are employed: the heat released from hydrogen addition in the organic liquid hydrogen storage system, the waste heat from the engine's turbocharging intercooling, the heating of the hydrogen-enriched organic liquid working fluid by the exhaust gas from the oxygen-enriched combustion hydrogen internal combustion engine, the heating of the hydrogen-enriched organic liquid working fluid by a hydrogen catalytic combustion supplementary energy device, and the supplementary energy from an electric heating device to address insufficient heat during cold starts and variable operating conditions. Furthermore, the present invention can control the hydrogen addition and dehydrogenation cycles of the organic liquid hydrogen storage system and the flow rates of hydrogen and oxygen in the internal combustion engine through a central control unit, intelligently controlling stable combustion and the emission of nitrogen oxides and unburned hydrogen to achieve zero carbon emissions and optimal operating conditions.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine is characterized by comprising an oxygen-enriched hydrogen combustion internal combustion engine and an organic liquid hydrogen storage (LOHC) system. The oxygen-enriched hydrogen combustion internal combustion engine achieves thermal conversion by burning hydrogen in an oxygen-enriched environment, and the required hydrogen fuel is provided by the LOHC system. The oxygen-enriched combustion hydrogen internal combustion engine has a hydrogen fuel inlet, an air inlet, and an oxygen inlet. The oxygen ratio in the oxidant is adjusted by the oxygen entering through the oxygen inlet, thus achieving oxygen-enriched combustion.

[0008] In one embodiment, the distributed energy system of the organic liquid hydrogen storage coupled with the oxygen-enriched hydrogen internal combustion engine further includes a buffer hydrogen storage tank, a hydrogen compressor, a cooler, an air compressor, and a generator; The buffer hydrogen storage tank buffers and stores hydrogen supplied by the organic liquid hydrogen storage system, providing a stable supply of hydrogen to the hydrogen compressor. The hydrogen compressor increases the hydrogen pressure to meet the operating requirements of the oxygen-enriched hydrogen combustion engine. After pressure increase, the hydrogen is passed into a cooler to lower its temperature and improve the hydrogen injection efficiency before entering the oxygen-enriched hydrogen combustion engine. Air enters the oxygen-enriched hydrogen combustion engine after passing through an air compressor. Oxygen is introduced into the oxygen-enriched hydrogen combustion engine from an oxygen storage tank, and the oxygen-enriched hydrogen combustion engine drives a generator to generate electricity.

[0009] In one embodiment, the organic liquid hydrogen storage system includes a hydrogen storage tank, a hydrogenation reactor, a hydrogen-rich organic working fluid storage tank, a dehydrogenation reactor, a hydrogen-poor organic working fluid storage tank, and a condenser.

[0010] The hydrogen stored in the hydrogen storage tank enters the hydrogenation reactor, where it undergoes an addition reaction with a hydrogen-poor organic liquid carrier (LOHC-H2) containing a large number of unsaturated bonds (such as aromatic rings or carbon-carbon double bonds) under the action of a catalyst. This reaction gradually saturates the unsaturated bonds with hydrogen atoms, thereby transforming the hydrogen into a chemically stable, hydrogen-rich organic liquid carrier (LOHC+H2) with a significantly improved hydrogen-carbon ratio, which is then stored in a hydrogen-rich organic working fluid storage tank.

[0011] When the oxygen-enriched hydrogen internal combustion engine requires hydrogen fuel input, the hydrogen-enriched organic liquid working medium (LOHC+H2) in the hydrogen-enriched organic working medium storage tank enters the dehydrogenation reactor. Under endothermic reaction, the hydrogen-enriched organic liquid working medium generates hydrogen-lean organic liquid working medium (LOHC-H2) and gaseous hydrogen. Part of the organic working medium is heated and vaporized, and the hydrogen-lean organic liquid working medium is returned to the hydrogen-lean organic working medium storage tank. Part of the gaseous organic working medium and hydrogen are passed into the condenser, so that the gaseous organic working medium is liquefied into hydrogen-lean organic liquid working medium, which is then passed into the hydrogen-lean organic working medium storage tank for recycling.

[0012] In one embodiment, the distributed energy system of organic liquid hydrogen storage coupled with oxygen-enriched hydrogen internal combustion engine further includes a wind and solar energy electrolysis water production hydrogen system, including a wind turbine, a photovoltaic power generation system, an electrolyzer, a hydrogen-oxygen gas separation system, and an oxygen storage tank. The wind turbine converts wind energy into electrical energy, and the photovoltaic power generation system converts solar energy into electrical energy to power the electrolyzer, thereby producing hydrogen and oxygen through water electrolysis. The hydrogen and oxygen are then separated by a hydrogen-oxygen gas separation system, with the hydrogen stored in a hydrogen storage tank and the oxygen stored in an oxygen storage tank.

[0013] In one embodiment, the dehydrogenation reactor of the organic liquid hydrogen storage system requires heat to be consumed in the dehydrogenation reaction, and the heat sources include an electric heating energy supplement device, a hydrogen catalytic combustion energy supplement device, a waste gas heat exchanger, and a heat storage device. The cooler reduces the temperature of hydrogen through heat exchange, and the heat exchanged is transferred to the dehydrogenation reactor to preheat the organic liquid working fluid; the heat storage device stores the heat released by the hydrogenation reaction in the hydrogenation reactor and supplies it to the dehydrogenation reactor. The exhaust gas heat exchanger has two inlets, which are connected to the exhaust gas outlet of the oxygen-enriched hydrogen internal combustion engine and the exhaust gas outlet of the hydrogen catalytic combustion energy replenishment device, respectively. The high-temperature exhaust gas from the oxygen-enriched hydrogen internal combustion engine introduces energy into the dehydrogenation reactor through the exhaust gas heat exchanger to improve system efficiency. The hydrogen catalytic combustion energy replenishment device has a hydrogen inlet connected to a cooler and an oxygen inlet connected to an oxygen storage tank. Through hydrogen-oxygen catalytic combustion, it utilizes the high-temperature characteristics of hydrogen-oxygen combustion to provide a stable and large amount of heat to the exhaust gas heat exchanger, further compensating for the heat of the exhaust gas from the oxygen-enriched hydrogen internal combustion engine and meeting the heat requirements of the dehydrogenation reactor.

[0014] The electric heating energy replenishment device supplies heat to the dehydrogenation reactor through electric heating when there is insufficient heat during startup, changing operating conditions, etc., to meet the dehydrogenation requirements.

[0015] In one embodiment, the distributed energy system of the organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine further includes a catalytic oxidation device and a selective catalytic reduction device. The exhaust gas after heat exchange is discharged to the catalytic oxidation device and then flows to the selective catalytic reduction device. The function of the catalytic oxidation device and the selective catalytic reduction device is to treat the exhaust gas after heat exchange so that the final exhaust gas from the system meets environmental protection requirements. Specifically, the catalytic oxidation device oxidizes unburned hydrogen in the exhaust gas into water vapor, and the selective catalytic reduction device converts nitrogen oxides contained in the exhaust gas into nitrogen. The final emissions are mainly composed of nitrogen and water vapor, achieving zero-carbon and pollution-free emissions.

[0016] In one embodiment, the distributed energy system of the organic liquid hydrogen storage coupled with the oxygen-rich hydrogen internal combustion engine further includes an energy storage and power distributor; The energy storage and power distributor distributes the electrical energy input from the grid during system startup to drive the various power-consuming components of the system. When the system generates electricity, it drives the generator to generate electricity through an oxygen-enriched hydrogen combustion engine for energy storage. In addition to driving the various power-consuming components of the system, it also connects the electrical energy to the grid. The energy storage and power distributor also has an energy storage function to provide electrical energy for subsequent system startup.

[0017] In one embodiment, the distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine is characterized by further including a central control unit; The central control unit uniformly controls all fuel supply components, valves, sensors, heat transfer systems, and detects the composition and content of emissions in the exhaust gas.

[0018] The operating method of the liquid ammonia-hydrogen-electric hybrid power engine system of the present invention includes: When the oxygen-enriched hydrogen internal combustion engine system is cold-started, the energy storage and power distributor drives the electric heating supplementary energy device to supply energy to the dehydrogenation reactor. The hydrogen-rich organic liquid working fluid undergoes a dehydrogenation reaction in the dehydrogenation reactor to produce hydrogen. The hydrogen is stabilized through a buffer hydrogen storage tank. The energy storage and power distributor drives the hydrogen compressor and condenser. Finally, the hydrogen is pressurized and cooled before entering the oxygen-enriched hydrogen internal combustion engine to burn and drive the generator to generate electricity. Stable power generation and grid connection are achieved through the energy storage and power distributor.

[0019] Once the oxygen-enriched hydrogen internal combustion engine starts running, the waste heat from the cooler is introduced into the dehydrogenation reactor to preheat the hydrogen-enriched organic liquid working fluid, reducing the energy consumption of the electric heating supplementary energy device; the high-temperature exhaust gas is introduced into the waste gas heat exchanger and then into the dehydrogenation reactor, further reducing the energy consumption of the electric heating supplementary energy device.

[0020] Once the oxygen-enriched hydrogen internal combustion engine is running stably, some of the excess hydrogen is fed into the hydrogen catalytic combustion supplementary energy device. Through hydrogen-oxygen catalytic combustion, the heat of the exhaust gas from the oxygen-enriched hydrogen internal combustion engine is further compensated, meeting the heat requirements of the dehydrogenation reactor. This replaces the electric heating supplementary energy device and improves system efficiency.

[0021] When fluctuating energy sources like wind and solar power are available, they are converted into electricity by wind turbines and photovoltaic power generation systems. This electricity is then fed into an electrolyzer to electrolyze water and produce hydrogen and oxygen. The hydrogen and oxygen are separated by a hydrogen-oxygen gas separation system and stored separately in tanks. Hydrogen is then introduced from the tanks into a hydrogenation reactor. A hydrogen-poor organic liquid working fluid is introduced into the hydrogenation reactor and undergoes an exothermic hydrogenation reaction to produce a hydrogen-rich organic liquid working fluid. The exothermic reaction is then introduced into a thermal storage device. The thermal storage device supplies heat to the dehydrogenation reactor, reducing the power consumption of the hydrogen catalytic combustion supplementary energy device, lowering the system's hydrogen consumption, and improving system efficiency.

[0022] In one embodiment, the oxygen-enriched hydrogen combustion internal combustion engine has a power range of 100-300 kW, the oxygen content of the oxidant does not exceed 40%, the hydrogen supply capacity of the organic liquid hydrogen storage system is 10-30 kg / h, and the overall efficiency of the entire system reaches 60%-80%.

[0023] Compared with existing technologies, this invention's distributed energy system, which uses organic liquid hydrogen storage coupled with an oxygen-enriched combustion hydrogen internal combustion engine, achieves safe and economical large-scale ambient temperature and pressure storage and transportation of hydrogen energy through organic liquid hydrogen storage. This avoids the risks and high energy consumption associated with high-pressure and cryogenic hydrogen storage, and can directly utilize existing petroleum infrastructure, significantly reducing retrofit costs. The coupling with the oxygen-enriched combustion hydrogen internal combustion engine technology significantly improves combustion efficiency and output power while reducing heat loss, achieving efficient and stable hydrogen power generation. Crucially, the system innovatively integrates a five-stage waste heat utilization pathway: heat from the hydrogen addition reaction, recovery of engine turbocharging and intercooling waste heat, oxygen-enriched combustion exhaust waste heat, hydrogen catalytic combustion supplementary heat, and electric heating auxiliary heat. This heat is precisely and efficiently used to heat the hydrogen-rich LOHC working fluid, maximizing the recovery of system waste heat and significantly improving overall energy utilization efficiency. This comprehensive solution effectively solves the core challenges of renewable energy volatility conversion, safe and economical hydrogen storage and transportation, and efficient and stable utilization. It provides a highly competitive technological path for building a safe, reliable, economical, efficient, and deeply decarbonized distributed energy system, strongly supporting the achievement of energy self-sufficiency and dual-carbon goals. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the system structure of the present invention. Detailed Implementation

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings and examples.

[0026] Traditional renewable energy hydrogen production and utilization routes face bottlenecks such as high risks and costs in hydrogen storage and transportation, as well as limitations in improving power generation efficiency and overall system energy efficiency. To address these challenges, this invention provides a distributed power generation system based on organic liquid hydrogen storage coupled with an oxygen-enriched combustion hydrogen internal combustion engine. On one hand, it utilizes an organic liquid carrier to achieve ambient temperature and pressure, intrinsic safety, and high-density hydrogen storage. On the other hand, the oxygen-enriched combustion hydrogen internal combustion engine at the power generation end directly utilizes hydrogen produced by LOHC dehydrogenation, significantly improving combustion efficiency, output power, and reducing heat loss through oxygen-enriched combustion. Crucially, the system innovatively deeply couples the multi-stage waste heat generated by the internal combustion engine with the strong heat absorption demand of LOHC dehydrogenation, precisely and efficiently providing heat for the dehydrogenation reaction through a five-stage cascade utilization, maximizing the recovery of system waste heat and significantly improving overall energy utilization efficiency. Ultimately, this technical route effectively solves the core problems of high volatility in renewable energy hydrogen production, unsafe and uneconomical hydrogen storage and transportation, and low overall energy efficiency of hydrogen power generation systems. It also keeps system pollutant emissions at a low level, providing a highly competitive technical path for building a safe, reliable, economical, efficient, and deeply decarbonized distributed energy system.

[0027] like Figure 1 As shown, the present invention is a distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine, mainly including an oxygen-enriched hydrogen combustion internal combustion engine 1 and an organic liquid hydrogen storage system. The oxygen-enriched hydrogen combustion internal combustion engine 1 achieves thermal conversion by burning hydrogen in an oxygen-enriched environment.

[0028] The oxygen-enriched combustion hydrogen internal combustion engine 1 of the present invention has a hydrogen fuel inlet, an air inlet, and an oxygen inlet. The oxygen ratio in the oxidant is adjusted by the oxygen inlet to achieve oxygen-enriched combustion.

[0029] Furthermore, to achieve stable hydrogen supply and power generation, the present invention also includes a buffer hydrogen storage tank 7, a hydrogen compressor 8, a cooler 9, an air compressor 10, and a generator 24.

[0030] The present invention includes a buffer hydrogen storage tank 7 that buffers and stores hydrogen supplied by an organic liquid hydrogen storage system, providing a stable supply of hydrogen to a hydrogen compressor 8. The hydrogen compressor 8 increases the hydrogen pressure to meet the operating requirements of the oxygen-enriched hydrogen internal combustion engine 1. After the pressure is increased, the hydrogen is introduced into a cooler 9 to lower the hydrogen temperature and improve the hydrogen injection efficiency entering the oxygen-enriched hydrogen internal combustion engine 1. Air enters the oxygen-enriched hydrogen internal combustion engine 1 after passing through an air compressor 10. Oxygen is introduced into the oxygen-enriched hydrogen internal combustion engine 1 from an oxygen storage tank 17, and the oxygen-enriched hydrogen internal combustion engine 1 drives a generator 24 to generate electricity.

[0031] Furthermore, the organic liquid hydrogen storage system of the present invention mainly includes a hydrogen storage tank 16, a hydrogenation reactor 2, a hydrogen-rich organic working fluid storage tank 3, a dehydrogenation reactor 4, a hydrogen-poor organic working fluid storage tank 5, and a condenser 6.

[0032] The hydrogen stored in the hydrogen storage tank 16 of this invention enters the hydrogenation reactor 2, where hydrogen reacts with the hydrogen-poor organic liquid working medium through a chemical reaction to generate a hydrogen-rich organic liquid working medium, which is then stored in the hydrogen-rich organic working medium storage tank 3.

[0033] Specifically, when the oxygen-enriched hydrogen internal combustion engine 1 requires hydrogen fuel input, the hydrogen-enriched organic liquid working medium LOHC+H2 in the hydrogen-enriched organic working medium storage tank 3 enters the dehydrogenation reactor 4. Under endothermic reaction, the hydrogen-enriched organic liquid working medium generates hydrogen-lean organic liquid working medium LOHC-H2 and gaseous hydrogen. Part of the organic working medium is heated and vaporized, and the hydrogen-lean organic liquid working medium is returned to the hydrogen-lean organic working medium storage tank 5. Part of the gaseous organic working medium and hydrogen are passed into the condenser 6, so that the gaseous organic working medium is liquefied into hydrogen-lean organic liquid working medium, which is then passed into the hydrogen-lean organic working medium storage tank 5 for recycling.

[0034] Furthermore, the present invention also includes a wind and solar energy electrolysis water hydrogen production system to better utilize renewable energy sources such as wind and solar power and mitigate their fluctuations. The wind and solar energy electrolysis water hydrogen production system mainly includes a wind turbine generator 11, a photovoltaic power generation system 12, an electrolyzer 14, a hydrogen-oxygen gas separation system 15, and an oxygen storage tank 17.

[0035] The wind turbine generator 11 of this invention converts wind energy into electrical energy, and the photovoltaic power generation system 12 converts solar energy into electrical energy, which supplies power to the electrolyzer 14 to produce hydrogen and oxygen by electrolysis of water. The hydrogen and oxygen are then separated by the hydrogen-oxygen gas separation system 15. The hydrogen is stored in the hydrogen storage tank 16 and the oxygen is stored in the oxygen storage tank 17.

[0036] Furthermore, the dehydrogenation reactor 4 of the organic liquid hydrogen storage system of the present invention requires heat to be consumed in the dehydrogenation reaction. The heat sources include an electric heating energy replenishment device 18, a hydrogen catalytic combustion energy replenishment device 19, a waste gas heat exchanger 20, and a heat storage device 21.

[0037] The cooler 9 of this invention reduces the temperature of hydrogen through heat exchange, and the heat exchanged is transferred to the dehydrogenation reactor 4 to preheat the organic liquid working medium; the heat storage device 21 stores the exothermic reaction in the hydrogenation reactor 2 and supplies it to the dehydrogenation reactor 4.

[0038] The exhaust gas heat exchanger 20 of this invention has two inlets, which are respectively connected to the exhaust gas outlet of the oxygen-enriched hydrogen internal combustion engine 1 and the exhaust gas outlet of the hydrogen catalytic combustion energy replenishment device 19. The high-temperature exhaust gas from the oxygen-enriched hydrogen internal combustion engine 1 is introduced into the dehydrogenation reactor 4 through the exhaust gas heat exchanger 20 to improve the system efficiency.

[0039] The hydrogen catalytic combustion energy replenishment device 19 of the present invention has a hydrogen inlet connected to a cooler 9 and an oxygen inlet connected to an oxygen storage tank 17. Through hydrogen-oxygen catalytic combustion, the high-temperature characteristics of hydrogen-oxygen combustion are utilized to provide stable and large amounts of heat to the exhaust gas heat exchanger 20, further compensating for the heat of the exhaust gas from the oxygen-enriched hydrogen internal combustion engine 1 and meeting the heat demand of the dehydrogenation reactor 4.

[0040] The electric heating energy replenishment device 18 of the present invention supplies heat to the dehydrogenation reactor 4 through electric heating when there is insufficient heat during startup, changing operating conditions, etc., to meet the dehydrogenation requirements.

[0041] In embodiments of the present invention, reference continues to be made. Figure 1 The distributed energy system of this organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine may further include: a catalytic oxidation device 22 and a selective catalytic reduction device 23. The exhaust gas after heat exchange is discharged to the catalytic oxidation device 22 and then flows to the selective catalytic reduction device 23. The function of the catalytic oxidation device 22 and the selective catalytic reduction device 23 is to treat the exhaust gas after heat exchange so that the final exhaust gas from the system meets environmental protection requirements. Specifically, the catalytic oxidation device 22 oxidizes unburned hydrogen in the exhaust gas into water vapor, and the selective catalytic reduction device 23 converts nitrogen oxides contained in the exhaust gas into nitrogen. The final emissions are mainly composed of nitrogen and water vapor, achieving zero-carbon and pollution-free emissions.

[0042] In embodiments of the present invention, reference continues to be made. Figure 1 The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine may further include: an energy storage and power distributor 25. When the system starts up, the energy storage and power distributor 25 distributes the electrical energy input from the grid to drive the various power-consuming components of the system; when the system generates electricity, it drives the generator 24 driven by the oxygen-enriched hydrogen combustion engine 1 to generate electricity for energy storage, and in addition to driving the various power-consuming components of the system, it connects the electrical energy to the grid; the energy storage and power distributor 25 also has an energy storage function to provide electrical energy for subsequent system startup.

[0043] In embodiments of the present invention, reference continues to be made. Figure 1 The distributed energy system of the organic liquid hydrogen storage coupled with the oxygen-enriched hydrogen internal combustion engine may also include: a central control unit 13. The central control unit 13 uniformly controls each fuel supply component, valve, sensor, heat transfer, and detects the composition and content of emissions in the exhaust gas.

[0044] For example, the oxygen-to-oxidant ratio of the oxygen-enriched hydrogen internal combustion engine 1 can be controlled by the central control unit 13 to not exceed 40%, under which the system can achieve better operating conditions. The power range of the oxygen-enriched hydrogen internal combustion engine 1 is 100-300 kW, the hydrogen supply capacity of the organic liquid hydrogen storage system is 10-30 kg / h, and the overall efficiency of the entire system reaches 60%-80%.

[0045] The operating method of the liquid ammonia-hydrogen-electric hybrid power engine system of the present invention includes: When the oxygen-enriched hydrogen internal combustion engine 1 system is cold-started, the energy storage and power distributor 25 drives the electric heating supplementary energy device 18 to supply energy to the dehydrogenation reactor 4. The hydrogen-enriched organic liquid working fluid undergoes a dehydrogenation reaction in the dehydrogenation reactor 4 to produce hydrogen. The hydrogen is stabilized through the buffer hydrogen storage tank 7. The energy storage and power distributor 25 drives the hydrogen compressor 8 and condenser 6. The hydrogen is finally pressurized and cooled before entering the oxygen-enriched hydrogen internal combustion engine 1 to burn and drive the generator 24 to generate electricity. Stable power generation and grid connection are achieved through the energy storage and power distributor 25.

[0046] When the oxygen-enriched hydrogen internal combustion engine 1 starts running, the waste heat from the cooler 9 is introduced into the dehydrogenation reactor 4 to preheat the hydrogen-enriched organic liquid working fluid, reducing the energy consumption of the electric heating supplementary energy device 18; the high-temperature exhaust gas is introduced into the exhaust gas heat exchanger 20 and then into the dehydrogenation reactor 4, further reducing the energy consumption of the electric heating supplementary energy device 18.

[0047] Once the oxygen-enriched hydrogen internal combustion engine 1 is running stably, some of the excess hydrogen is introduced into the hydrogen catalytic combustion supplementary energy device 19. Through hydrogen-oxygen catalytic combustion, the heat of the exhaust gas from the oxygen-enriched hydrogen internal combustion engine 1 is further compensated, meeting the heat requirements of the dehydrogenation reactor 4. This replaces the electric heating supplementary energy device 18 and improves system efficiency.

[0048] When fluctuating wind and solar energy are available, they are converted into electrical energy by wind turbine 11 and photovoltaic power generation system 12, and then fed into electrolyzer 14 to electrolyze water to produce hydrogen and oxygen. The hydrogen and oxygen gas separation system 15 separates the gases and stores them separately in storage tanks. Hydrogen is introduced from the storage tank into hydrogenation reactor 2. Hydrogen-poor organic liquid working medium is introduced into hydrogenation reactor 2 and hydrogen-rich organic liquid working medium is produced through hydrogenation exothermic reaction. The exothermic reaction is introduced into heat storage device 21. Heat storage device 21 supplies heat to dehydrogenation reactor 4, reducing the power of hydrogen catalytic combustion supplementary energy device 19, reducing system hydrogen consumption, and improving system efficiency.

[0049] In summary, this system releases hydrogen online through an organic liquid hydrogen storage carrier dehydrogenation device to provide fuel for a hydrogen internal combustion engine. By coupling a five-stage waste heat recovery system, it precisely and efficiently provides the necessary heat energy for the strongly endothermic dehydrogenation reaction of LOHC. This invention intelligently coordinates the dehydrogenation rate and optimizes waste heat utilization through a central control unit. Ultimately, this system achieves safe and economical storage and transportation of hydrogen produced from renewable energy, efficient and stable power generation from low-purity hydrogen, and deep recovery and utilization of medium- and low-temperature waste heat within the system, significantly improving overall energy efficiency and achieving the goal of deep decarbonization power generation.

[0050] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, shall fall within the scope of protection of the present invention.

Claims

1. A distributed energy system for organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine, characterized in that, It includes an oxygen-enriched hydrogen combustion internal combustion engine (1) and an organic liquid hydrogen storage system, wherein the organic liquid hydrogen storage system provides hydrogen fuel to the oxygen-enriched hydrogen combustion internal combustion engine (1), and the oxygen-enriched hydrogen combustion internal combustion engine (1) achieves thermal conversion by burning hydrogen in an oxygen-enriched environment; The oxygen-enriched combustion hydrogen internal combustion engine (1) has a hydrogen fuel inlet, an air inlet, and an oxygen inlet. The oxygen ratio in the oxidant is adjusted by the oxygen inlet to achieve oxygen-enriched combustion.

2. The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claim 1, characterized in that, The organic liquid hydrogen storage system includes a hydrogen storage tank (16), a hydrogenation reactor (2), a hydrogen-rich organic working fluid storage tank (3), a dehydrogenation reactor (4), a hydrogen-poor organic working fluid storage tank (5), and a condenser (6). The hydrogen stored in the hydrogen storage tank (16) enters the hydrogenation reactor (2), where hydrogen reacts with the hydrogen-poor organic liquid working medium through a chemical reaction to generate a hydrogen-rich organic liquid working medium, which is then stored in the hydrogen-rich organic working medium storage tank (3). When the oxygen-enriched combustion hydrogen internal combustion engine (1) requires hydrogen fuel input, the hydrogen-enriched organic liquid working medium in the hydrogen-enriched organic working medium storage tank (3) enters the dehydrogenation reactor (4). The hydrogen-enriched organic liquid working medium generates hydrogen-poor organic liquid working medium and hydrogen under endothermic reaction. Part of the organic working medium is heated and vaporized, and the hydrogen-poor organic liquid working medium is returned to the hydrogen-poor organic working medium storage tank (5). Part of the gaseous organic working medium and hydrogen are introduced into the condenser (6) to liquefy the gaseous organic working medium into hydrogen-poor organic liquid working medium, which is then introduced into the hydrogen-poor organic working medium storage tank (5) for recycling. The hydrogen is then sent to the oxygen-enriched combustion hydrogen internal combustion engine (1).

3. The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claim 2, characterized in that, It also includes a buffer hydrogen storage tank (7), a hydrogen compressor (8), a cooler (9), an air compressor (10), and a generator (24). The buffer hydrogen storage tank (7) buffers and stores the hydrogen supplied by the organic liquid hydrogen storage system, and stably supplies hydrogen to the hydrogen compressor (8). The hydrogen compressor (8) increases the hydrogen pressure to meet the usage requirements of the oxygen-enriched combustion hydrogen internal combustion engine (1). After increasing the pressure, the hydrogen is introduced into the cooler (9) to reduce the hydrogen temperature and increase the hydrogen injection efficiency entering the oxygen-enriched combustion hydrogen internal combustion engine (1). Air enters the oxygen-enriched combustion hydrogen internal combustion engine (1) after passing through the air compressor (10). Oxygen is introduced into the oxygen-enriched combustion hydrogen internal combustion engine (1) from the oxygen storage tank (17). The oxygen-enriched combustion hydrogen internal combustion engine (1) drives the generator (24) to generate electricity.

4. The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claim 3, characterized in that, The heat sources for the dehydrogenation reactor (4) of the organic liquid hydrogen storage system in the dehydrogenation reaction include an electric heating supplementary energy device (18), a hydrogen catalytic combustion supplementary energy device (19), a waste gas heat exchanger (20), and a heat storage device (21). The cooler (9) reduces the temperature of hydrogen through heat exchange, and the heat exchanged is transferred to the dehydrogenation reactor (4) to preheat the organic liquid working medium; the heat storage device (21) stores the heat released by the hydrogenation reaction in the hydrogenation reactor (2) and supplies it to the dehydrogenation reactor (4). The exhaust gas heat exchanger (20) has two inlets, which are connected to the exhaust gas outlet of the oxygen-enriched combustion hydrogen internal combustion engine (1) and the exhaust gas outlet of the hydrogen catalytic combustion energy replenishment device (19), respectively. The high-temperature exhaust gas from the combustion of the oxygen-enriched combustion hydrogen internal combustion engine (1) introduces energy into the dehydrogenation reactor (4) through the exhaust gas heat exchanger (20) to improve the system efficiency. The hydrogen catalytic combustion energy replenishment device (19) has a hydrogen inlet connected to the cooler (9) and an oxygen inlet connected to the oxygen storage tank (17). Through hydrogen-oxygen catalytic combustion, the high temperature characteristics of hydrogen-oxygen combustion are utilized to provide heat to the exhaust gas heat exchanger (20), compensate for the heat of the exhaust gas of the oxygen-enriched hydrogen internal combustion engine (1), and meet the heat demand of the dehydrogenation reactor (4). The electric heating energy replenishment device (18) supplies heat to the dehydrogenation reactor (4) through electric heating when the heat is insufficient, thereby meeting the dehydrogenation requirements.

5. The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claim 4, characterized in that, It also includes a catalytic oxidation device (22) and a selective catalytic reduction device (23). The waste gas heat exchanger (20) discharges the heat-exchanged waste gas to the catalytic oxidation device (22) and then flows to the selective catalytic reduction device (23). The catalytic oxidation device (22) oxidizes the unburned hydrogen in the waste gas into water vapor, and the selective catalytic reduction device (23) converts the nitrogen oxides contained in the waste gas into nitrogen, so that the exhaust gas of the final system meets the environmental protection requirements.

6. The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claim 3, characterized in that, It also includes energy storage and power distributors (25); The energy storage and power distributor (25) distributes the electrical energy input from the grid when the system starts up, driving the various power-consuming components of the system; when the system generates electricity, it drives the generator (24) to generate electricity from the oxygen-enriched hydrogen combustion engine (1) to store energy, and in addition to driving the various power-consuming components of the system, it connects the electrical energy to the grid; the energy storage and power distributor (25) also has an energy storage function to provide electrical energy for subsequent system startup.

7. The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claim 1, characterized in that, It also includes a wind and solar energy electrolysis water hydrogen production system; the wind and solar energy electrolysis water hydrogen production system includes a wind turbine (11), a photovoltaic power generation system (12), an electrolyzer (14), a hydrogen-oxygen gas separation system (15) and an oxygen storage tank (17). The wind turbine (11) converts wind energy into electrical energy, and the photovoltaic power generation system (12) converts solar energy into electrical energy to supply power to the electrolyzer (14) to produce hydrogen and oxygen by electrolysis of water. The hydrogen and oxygen are then separated by the hydrogen-oxygen gas separation system (15). The hydrogen is stored in the hydrogen storage tank (16), and the oxygen is stored in the oxygen storage tank (17).

8. The distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claim 1, characterized in that, It also includes a central control unit (13); The central control unit (13) uniformly controls each fuel supply component, valve, sensor, heat transfer, and detects the composition and content of emissions in the exhaust gas.

9. The operating method of the distributed energy system of organic liquid hydrogen storage coupled with an oxygen-enriched hydrogen internal combustion engine according to claims 1 to 8, characterized in that: When the oxygen-enriched combustion hydrogen internal combustion engine (1) system is cold-started, the energy storage and power distributor (25) drives the electric heating supplement device (18) to supply energy to the dehydrogenation reactor (4). The hydrogen-enriched organic liquid working medium undergoes a dehydrogenation reaction in the dehydrogenation reactor (4) to produce hydrogen. The hydrogen is stabilized through the buffer hydrogen storage tank (7). The energy storage and power distributor (25) drives the hydrogen compressor (8) and condenser (6). The hydrogen is finally pressurized and cooled before entering the oxygen-enriched combustion hydrogen internal combustion engine (1) to burn and do work to drive the generator (24) to generate electricity. The electricity is then connected to the grid through the energy storage and power distributor (25). When the oxygen-rich combustion hydrogen internal combustion engine (1) starts running, the residual heat of the cooler (9) is introduced into the dehydrogenation reactor (4) to preheat the hydrogen-rich organic liquid working fluid. The high-temperature exhaust gas is introduced into the exhaust gas heat exchanger (20) and introduced into the dehydrogenation reactor (4) to reduce the energy consumption of the electric heating supplementary energy device (18). After the oxygen-enriched combustion hydrogen internal combustion engine (1) is running stably, some of the excess hydrogen is introduced into the hydrogen catalytic combustion energy replenishment device (19). Through hydrogen-oxygen catalytic combustion, the heat of the exhaust gas of the oxygen-enriched combustion hydrogen internal combustion engine (1) is replenished, the heat demand of the dehydrogenation reactor (4) is met, and the electric heating energy replenishment device (18) is replaced. When wind and solar energy fluctuations are present, they are converted into electrical energy through wind turbine (11) and photovoltaic power generation system (12), and then fed into electrolyzer (14) to electrolyze water to produce hydrogen and oxygen. The hydrogen and oxygen gas separation system (15) separates the gases and stores them in storage tanks. Hydrogen is introduced from hydrogen storage tank (16) into hydrogenation reactor (2). Hydrogen-poor organic liquid working medium is introduced into hydrogenation reactor (2) and hydrogen-rich organic liquid working medium is generated through hydrogenation exothermic reaction. The exothermic reaction is introduced into heat storage device (21). Heat storage device (21) supplies heat to dehydrogenation reactor (4) to reduce the power of hydrogen catalytic combustion supplementary energy device (19).

10. The working method according to claim 9, characterized in that, The oxygen-enriched combustion hydrogen internal combustion engine (1) has a power range of 100-300 kW, the oxygen content of the oxidant does not exceed 40%, the hydrogen supply capacity of the organic liquid hydrogen storage system is 10-30 kg / h, and the overall efficiency of the entire system reaches 60%-80%.

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