CN-122014404-A - Distributed energy system of organic liquid hydrogen storage coupling oxygen-enriched hydrogen internal combustion engine and working method thereof

CN122014404ACN 122014404 ACN122014404 ACN 122014404ACN-122014404-A

Abstract

The invention discloses a distributed energy system of an organic liquid hydrogen storage coupling oxygen-enriched hydrogen internal combustion engine and a working method thereof, wherein the system comprises an oxygen-enriched hydrogen 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 an exhaust gas outlet, wherein the dehydrogenation endothermic reaction heat sources of the organic liquid hydrogen storage system have five paths, namely, hydrogenation reaction heat release of the organic liquid hydrogen storage system, recovery of engine waste heat, supercharging inter-cooling heat of the oxygen-enriched hydrogen internal combustion engine, hydrogen catalytic combustion heat supplement and electric heating assistance.

Inventors

WANG JINHUA
WEI XUTAO
WANG ZETAO
DAI HUIYANG
TAO KAIFENG
ZHANG MENG
HUANG ZUOHUA

Assignees

西安交通大学

Dates

Publication Date: 20260512
Application Date: 20260313

Claims (10)

1. The distributed energy system of the organic liquid hydrogen storage coupling oxygen-enriched hydrogen internal combustion engine is characterized by comprising an oxygen-enriched combustion hydrogen internal combustion engine (1) and an organic liquid hydrogen storage system, wherein the organic liquid hydrogen storage system provides hydrogen fuel for the oxygen-enriched combustion hydrogen internal combustion engine (1), and the oxygen-enriched combustion hydrogen internal combustion engine (1) realizes thermal conversion by combusting hydrogen in an oxygen-enriched environment; the oxygen-enriched combustion hydrogen internal combustion engine (1) is provided with a hydrogen fuel inlet, an air inlet and an oxygen inlet, and the oxygen proportion in the oxidant is adjusted by oxygen inlet so as to realize oxygen-enriched combustion.
2. The distributed energy system of an organic liquid hydrogen storage coupled oxygen-enriched hydrogen internal combustion engine of claim 1, wherein the organic liquid hydrogen storage system comprises a hydrogen storage tank (16), a hydrogenation reactor (2), a hydrogen-enriched organic working medium storage tank (3), a dehydrogenation reactor (4), a hydrogen-depleted organic working medium storage tank (5) and a condenser (6); The hydrogen stored in the hydrogen storage tank (16) enters the hydrogenation reactor (2), the hydrogen and the hydrogen-poor organic liquid working medium react through chemical reaction to generate the hydrogen-rich organic liquid working medium, and the hydrogen-rich organic liquid working medium is stored in the hydrogen-rich organic working medium storage tank (3); When the oxygen-enriched combustion hydrogen internal combustion engine (1) needs hydrogen fuel input, a hydrogen-enriched organic liquid working medium in a hydrogen-enriched organic working medium storage tank (3) enters a dehydrogenation reactor (4), the hydrogen-enriched organic liquid working medium generates a hydrogen-depleted organic liquid working medium and hydrogen under an endothermic reaction, part of the organic working medium is heated and gasified, the hydrogen-depleted organic liquid working medium flows back to the hydrogen-depleted organic working medium storage tank (5), part of gaseous organic working medium and hydrogen are introduced into a condenser (6), so that the gaseous organic working medium is liquefied into the hydrogen-depleted organic liquid working medium, the hydrogen-depleted organic working medium is introduced into the hydrogen-depleted organic working medium storage tank (5) for recycling, and the hydrogen is fed into the oxygen-enriched combustion hydrogen internal combustion engine (1).
3. The distributed energy system of an organic liquid hydrogen storage coupled oxygen-enriched hydrogen internal combustion engine of claim 2, further comprising a buffer hydrogen storage tank (7), a hydrogen compressor (8), a cooler (9) and an air compressor (10) and a generator (24); The buffer hydrogen storage tank (7) buffers and stores hydrogen supplied by the organic liquid hydrogen storage system, hydrogen is stably supplied to the hydrogen compressor (8), the hydrogen compressor (8) increases hydrogen pressure, the use requirement of the oxygen-enriched combustion hydrogen internal combustion engine (1) is met, after the hydrogen pressure is increased, the hydrogen is introduced into the cooler (9), the temperature of the hydrogen is reduced, the hydrogen injection efficiency of the oxygen-enriched combustion hydrogen internal combustion engine (1) is improved, 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), and the oxygen-enriched combustion hydrogen internal combustion engine (1) drives the generator (24) to generate electricity.
4. A distributed energy system of an organic liquid hydrogen storage coupled oxygen enriched hydrogen internal combustion engine according to claim 3, wherein the heat source of the dehydrogenation reactor (4) of the organic liquid hydrogen storage system in the dehydrogenation reaction comprises an electric heating energy supplementing device (18), a hydrogen catalytic combustion energy supplementing device (19), an exhaust gas heat exchanger (20) and a heat storage device (21); the cooler (9) reduces the temperature of hydrogen through heat exchange, and the heat of the heat exchange is transferred to the dehydrogenation reactor (4) to preheat the organic liquid working medium; the exhaust gas heat exchanger (20) is provided with two inlets which are respectively connected with the exhaust gas at the outlet of the oxygen-enriched combustion hydrogen internal combustion engine (1) and the exhaust gas at the outlet of the hydrogen catalytic combustion energy supplementing device (19), and the high-temperature exhaust gas combusted by the oxygen-enriched combustion hydrogen internal combustion engine (1) leads energy into the dehydrogenation reactor (4) through the exhaust gas heat exchanger (20) to realize the improvement of the system efficiency; the hydrogen catalytic combustion energy supplementing device (19) is provided with a hydrogen inlet connected with the cooler (9), an oxygen inlet connected with the oxygen storage tank (17), and the hydrogen and oxygen catalytic combustion is utilized to realize the heat supply for the waste gas heat exchanger (20) by utilizing the high-temperature characteristic of hydrogen and oxygen combustion, so that the heat of the tail gas of the oxygen-enriched combustion hydrogen internal combustion engine (1) is compensated, and the heat requirement of the dehydrogenation reactor (4) is met; The electric heating energy supplementing device (18) supplies heat to the dehydrogenation reactor (4) through electric heating when the heat is insufficient, so that the dehydrogenation requirement is met.
5. The distributed energy system of the organic liquid hydrogen storage coupled oxygen-enriched hydrogen internal combustion engine according to claim 4, further comprising a catalytic oxidation device (22) and a selective catalytic reduction device (23), wherein the waste gas after heat exchange is discharged from the waste gas heat exchanger (20) to the catalytic oxidation device (22) and then flows to the selective catalytic reduction device (23), the catalytic oxidation device (22) oxidizes unburned hydrogen in the waste gas into steam, and the selective catalytic reduction device (23) converts nitrogen oxides contained in the waste gas into nitrogen so that the tail gas of the final discharge system meets the environmental protection requirement.
6. A distributed energy system of an organic liquid hydrogen storage coupled oxygen enriched hydrogen internal combustion engine according to claim 3, further comprising a storage and power distributor (25); the power storage and electric energy distributor (25) distributes electric energy input by a power grid when the system is started to drive each power consumption component of the system, drives the oxygen-enriched combustion hydrogen internal combustion engine (1) to generate electricity to store the energy when the system generates electricity, and connects the electric energy except for driving each power consumption component of the system, wherein the power storage and electric energy distributor (25) also has a power storage function to provide the electric energy for the subsequent system starting.
7. The distributed energy system of the organic liquid hydrogen storage coupling oxygen-enriched hydrogen internal combustion engine according to claim 1, further comprising a wind-light energy water electrolysis hydrogen production system, wherein the wind-light energy water electrolysis hydrogen production system comprises a wind driven generator (11), a photovoltaic power generation system (12), an electrolysis tank (14), an oxyhydrogen gas separation system (15) and an oxygen storage tank (17); the wind driven generator (11) converts wind energy into electric energy, the photovoltaic power generation system (12) converts solar energy into electric energy, power is supplied to the electrolytic tank (14) to realize hydrogen production and oxygen production by water electrolysis, the hydrogen is stored in the hydrogen storage tank (16) and the oxygen is stored in the oxygen storage tank (17) by introducing the oxyhydrogen gas separation system (15) to realize separation.
8. The distributed energy system of an organic liquid hydrogen storage coupled oxygen-enriched hydrogen internal combustion engine according to claim 1, further comprising a central control unit (13); the central control unit (13) uniformly controls the fuel supply components, valves and sensors, and transmits heat and detects the components and the content of the emissions in the exhaust gas.
9. The method of operating a distributed energy system for an organic liquid hydrogen storage coupled oxygen-enriched hydrogen internal combustion engine of claims 1 to 8, wherein: When the oxygen-enriched combustion hydrogen internal combustion engine (1) is started in a system cold mode, an electric power storage and energy distributor (25) drives an electric heating energy supplementing device (18) to supply energy to the dehydrogenation reactor (4), a dehydrogenation reaction of the hydrogen-enriched organic liquid working medium occurs in the dehydrogenation reactor (4) to generate hydrogen, the hydrogen realizes voltage stabilization through a buffer hydrogen storage tank (7), the electric power storage and energy distributor (25) drives a hydrogen compressor (8) and a condenser (6), the hydrogen finally enters the oxygen-enriched combustion hydrogen internal combustion engine (1) for compression cooling to burn and do work to drive a generator (24) to generate electricity, and the electricity generation grid connection is realized through the electric power storage and energy distributor (25); After the oxygen-enriched combustion hydrogen internal combustion engine (1) starts to run, the residual heat of the cooler (9) is introduced into the dehydrogenation reactor (4), the hydrogen-enriched organic liquid working medium is preheated, the high-temperature tail gas is introduced into the waste gas heat exchanger (20), and the high-temperature tail gas is introduced into the dehydrogenation reactor (4), so that the energy consumption of the electric heating energy supplementing device (18) is reduced; after the oxygen-enriched combustion hydrogen internal combustion engine (1) stably operates, part of excess hydrogen is introduced into the hydrogen catalytic combustion energy supplementing device (19), and the tail gas heat of the oxygen-enriched combustion hydrogen internal combustion engine (1) is supplemented by hydrogen and oxygen catalytic combustion, so that the heat requirement of a dehydrogenation reactor (4) is met, and the hydrogen catalytic combustion energy supplementing device (18) is replaced; When wind energy and solar energy fluctuation energy exists, the wind energy and solar energy fluctuation energy is converted into electric energy through a wind driven generator (11) and a photovoltaic power generation system (12), the electric energy is introduced into an electrolytic tank (14) to electrolyze water to prepare hydrogen and oxygen, gas separation is realized through a hydrogen and oxygen gas separation system (15) and the hydrogen and oxygen gas separation systems are respectively stored in a storage tank, hydrogen is introduced into a hydrogenation reactor (2) from a hydrogen storage tank (16), a hydrogen-poor organic liquid working medium is introduced into the hydrogenation reactor (2) to generate a hydrogen-rich organic liquid working medium through hydrogenation exothermic reaction, reaction exothermic heat is introduced into a heat storage device (21), the heat storage device (21) supplies heat to the dehydrogenation reactor (4), and the power of a hydrogen catalytic combustion energy supplementing device (19) is reduced.
10. The working method according to claim 9, wherein the power range of the oxygen-enriched combustion hydrogen internal combustion engine (1) is 100-300 kW, the oxygen accounts for not more than 40% of the oxidant, the hydrogen supply capacity of the organic liquid hydrogen storage system is 10-30 kg/h, and the comprehensive efficiency of the whole system reaches 60% -80%.

Description

Distributed energy system of organic liquid hydrogen storage coupling oxygen-enriched hydrogen internal combustion engine and working method thereof Technical Field The invention relates to a distributed energy power generation system, in particular to a distributed energy system of an organic liquid hydrogen storage coupling oxygen-enriched hydrogen internal combustion engine and a working method thereof. Background Renewable wind energy and solar energy are fluctuation energy sources, and stable power generation cannot be realized. The conversion of renewable energy sources into hydrogen energy is an important way to achieve energy source independent control and dual carbon targets. However, high pressure hydrogen or high energy consumption for liquefaction storage is not suitable for mass hydrogen storage. The organic liquid hydrogen storage (LOHC) mode is to reversibly store hydrogen through liquid organic matters at normal temperature and normal pressure, avoids explosion risk of high-pressure gaseous hydrogen storage and extremely low temperature cost of liquid hydrogen, has high volume hydrogen storage density, can directly utilize the existing petroleum storage and transportation facilities, greatly reduces the transformation cost of hydrogen energy infrastructure, and is a path for solving the bottleneck of large-scale application and storage and transportation of hydrogen energy. The hydrogen energy utilization power generation end has high heat efficiency, can directly use low-purity hydrogen, can inherit the traditional internal combustion engine parts, has low transformation cost, is suitable for a distributed power generation scene, and is one of technical routes for hydrogen energy scale application. The stable power generation of hydrogen energy can be realized through the coupling of the organic liquid hydrogen storage and the hydrogen internal combustion engine, but how to design a system and how to realize the cascade utilization of waste heat to improve the comprehensive efficiency of the system is a key difficulty. Disclosure of Invention In order to overcome the difficulties in the prior art, the invention aims to provide a distributed energy system of an organic liquid hydrogen storage coupling oxygen-enriched combustion hydrogen internal combustion engine and a working method thereof, wherein a technical route of oxygen-enriched combustion of the hydrogen internal combustion engine is selected to improve combustion efficiency, improve power output, shorten combustion time and reduce heat loss. In the aspect of waste heat utilization, the hydrogenation exothermic reaction heat of the organic liquid hydrogen storage system, the hydrogen-rich organic liquid working medium of waste heat of the supercharging intercooling heat of the engine, the hydrogen-rich organic liquid working medium of tail gas heating of the oxygen-enriched combustion hydrogen internal combustion engine, the hydrogen catalytic combustion energy supplementing device and the cold start and the heat shortage of the variable working condition are selected, and the waste heat utilization is realized in five ways. In addition, the invention can also control hydrogenation and dehydrogenation circulation of the organic liquid hydrogen storage system and flow of hydrogen and oxygen of the internal combustion engine through the central control unit, intelligently control stable combustion and emission of nitrogen oxides and unburned hydrogen, realize zero carbon emission and reach the optimal running state. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: the distributed energy system is characterized by comprising an oxygen-enriched combustion hydrogen internal combustion engine and an organic liquid hydrogen storage (LOHC) system, wherein the oxygen-enriched combustion hydrogen internal combustion engine realizes thermal conversion by combusting 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 is provided with a hydrogen fuel inlet, an air inlet and an oxygen inlet, and the oxygen ratio in the oxidant is adjusted by the oxygen inlet of the oxygen inlet so as to realize oxygen-enriched combustion. In one embodiment, the distributed energy system of the organic liquid hydrogen storage coupled oxygen-enriched hydrogen internal combustion engine further comprises a buffer hydrogen storage tank, a hydrogen compressor, a cooler, an air compressor and a generator; The buffer hydrogen storage tank buffers and stores the hydrogen supplied by the organic liquid hydrogen storage system, the hydrogen is stably supplied to the hydrogen compressor, the hydrogen pressure is increased by the hydrogen compressor, the use requirement of the oxygen-enriched combustion hydrogen internal combustion engine is met, the hydrogen is introduced into the cooler after the pressu