CN-122015424-A - Liquid hydrogen production device and working method thereof

CN122015424ACN 122015424 ACN122015424 ACN 122015424ACN-122015424-A

Abstract

The application discloses a liquid hydrogen production device and a working method thereof, wherein the liquid hydrogen production device comprises a first heat exchanger, a pipe mechanism, a conversion mechanism, a cooling mechanism and a valve group, wherein the first heat exchanger is provided with a second cooling medium inlet, a first inlet and a first outlet, the pipe mechanism comprises a first cooling pipe, and the first cooling pipes are connected with the first heat exchanger. The valve group comprises a second throttle valve, the second throttle valve is arranged on the first cooling pipe, the first cooling pipe is communicated with the first outlet and the second cooling medium inlet, circulating hydrogen entering the first heat exchanger from the first inlet exchanges heat with circulating hydrogen subjected to temperature and pressure reduction by the temperature reducing mechanism, and the circulating hydrogen flows into the first cooling pipe from the first outlet, is throttled by the second throttle valve and enters the first heat exchanger from the second cooling medium inlet. The raw material hydrogen is cooled by the way of the expansion continuous refrigeration of the cooling mechanism and the high-pressure throttling refrigeration, so that the energy saving is realized, and meanwhile, the product hydrogen with the para-hydrogen content of 97% is produced.

Inventors

WU LIUFANG
ZHANG ZHENGXIONG
ZHANG QINGCHUAN

Assignees

上海联风气体有限公司

Dates

Publication Date: 20260512
Application Date: 20260302

Claims (10)

1. Liquid hydrogen production device, characterized in that, liquid hydrogen production device includes: A first heat exchanger forming a raw material inlet, a product hydrogen outlet, a first cooling medium inlet, a second cooling medium inlet, a first inlet and a first outlet, high-pressure raw material hydrogen enters the first heat exchanger through the raw material inlet, and high-pressure circulating hydrogen enters the first heat exchanger from the first cooling medium inlet and the first inlet respectively; a tube mechanism including a first tube group, a second tube group, and a first cooling tube, the first tube group, the second tube group, and the first cooling tube being connected to the first heat exchanger; The conversion mechanism comprises a plurality of first n-para-hydrogen converters, the first n-para-hydrogen converters are arranged on the first pipe group, raw material hydrogen is subjected to n-para-hydrogen conversion in the first n-para-hydrogen converters and high-pressure product hydrogen is produced, and the high-pressure product hydrogen is discharged from a product hydrogen outlet; The cooling mechanism comprises a plurality of expansion machines, the expansion machines are arranged on the second pipe group, and circulating hydrogen output by the second pipe group sequentially flows through the expansion machines and returns to the first heat exchanger; the valve bank comprises a second throttle valve, the second throttle valve is arranged on the first cooling pipe, the first cooling pipe is communicated with the first outlet and the second cooling medium inlet, and circulating hydrogen discharged from the first outlet flows back to the first heat exchanger from the second cooling medium inlet through the second throttle valve.
2. The liquid hydrogen production apparatus according to claim 1, wherein the conversion mechanism includes four of the first normal-para-hydrogen converters, the four of the first normal-para-hydrogen converters being defined as a first converter, a second converter, a third converter, and a fourth converter in this order, the first tube group including a first intake tube, a first exhaust tube, a second intake tube, a second exhaust tube, a third intake tube, a third exhaust tube, a fourth intake tube, and a fourth exhaust tube; The first air inlet pipe and the first air outlet pipe are connected with the first converter and the first heat exchanger, raw material hydrogen entering the first heat exchanger from the raw material inlet exchanges heat with a cooling medium for the first time, then flows to the first converter through the first air outlet pipe, is converted into normal secondary hydrogen in the first converter, and then is input into the first heat exchanger through the first air inlet pipe to exchange heat with the cooling medium for the second time; The second air inlet pipe and the second air outlet pipe are connected with the second converter and the first heat exchanger, raw material hydrogen subjected to second heat exchange in the first heat exchanger flows to the second converter through the second air outlet pipe, and then is input into the first heat exchanger through the second air inlet pipe to perform third heat exchange with a cooling medium; The third air inlet pipe and the third air outlet pipe are connected with the third converter and the first heat exchanger, raw material hydrogen subjected to third heat exchange in the first heat exchanger flows to the third converter through the third air outlet pipe, and then is input into the first heat exchanger through the third air inlet pipe to perform fourth heat exchange with a cooling medium; the fourth air inlet pipe and the fourth air outlet pipe are connected with the fourth converter and the first heat exchanger, raw material hydrogen after fourth heat exchange in the first heat exchanger flows to the fourth converter through the fourth air outlet pipe, and the raw material hydrogen is converted into high-pressure product hydrogen and then is input into the first heat exchanger through the fourth air inlet pipe to perform fifth heat exchange with a cooling medium.
3. The liquid hydrogen production apparatus according to claim 2, wherein the first heat exchanger forms a first cooling medium outlet, the cooling mechanism includes three of the expanders, the three expanders are defined as a first expander, a second expander, and a third expander in this order, and the second tube group includes a first output tube, a first input tube, a second output tube, a second input tube, a third output tube, and a third input tube; the first output pipe and the first input pipe are connected with the first expander and the first heat exchanger, and circulating hydrogen entering the first heat exchanger from the first cooling medium inlet exchanges heat with raw material hydrogen for the first time, then is introduced into the first expander through the first output pipe, and then flows back to the first heat exchanger through the first input pipe to exchange heat with the raw material hydrogen for the second time; The second output pipe and the second input pipe are connected with the second expander and the first heat exchanger, and circulating hydrogen after second heat exchange in the first heat exchanger is introduced into the second expander through the second output pipe and then flows back to the first heat exchanger through the second input pipe to perform third heat exchange with raw material hydrogen; The third output pipe and the third input pipe are connected with the third expander and the first heat exchanger, circulating hydrogen after third heat exchange in the first heat exchanger is led into the third expander through the third output pipe, then flows back to the first heat exchanger through the third input pipe to perform fourth heat exchange with raw material hydrogen, and is discharged from the first cooling medium outlet after fourth heat exchange.
4. The liquid hydrogen production device according to claim 3, wherein the liquid hydrogen production equipment further comprises a first liquefaction tank, the valve group comprises a first throttle valve, the pipe mechanism comprises a third pipe group, the third pipe group comprises a first exhaust pipe, a first liquid discharge pipe and a second exhaust pipe, the first exhaust pipe is connected to the product hydrogen outlet and the first liquefaction tank, the first throttle valve is arranged on the first exhaust pipe, high-pressure product hydrogen discharged from the product hydrogen outlet enters the first liquefaction tank after being throttled by the first throttle valve through the first exhaust pipe, the high-pressure product hydrogen is converted into medium-pressure liquid hydrogen and medium-pressure product hydrogen under the throttling action of the first throttle valve, the first liquid discharge pipe is connected to the first liquefaction tank, medium-pressure liquid hydrogen is discharged from the first exhaust pipe through the first liquid discharge pipe, the first heat exchanger further forms a first reflux port, the second reflux port is connected to the first exhaust pipe, the high-pressure product hydrogen discharged from the product hydrogen outlet enters the first liquefaction tank through the first reflux port and the first heat exchanger as a medium for cooling medium of the medium-pressure hydrogen in the first heat exchanger.
5. The liquid hydrogen production apparatus according to claim 4, wherein the third pipe group further includes a second drain pipe, the valve group includes a third throttle valve, and one end of the second drain pipe is connected to a pipe disposed between the first outlet and the second throttle valve, and the other end is connected to the first liquefaction tank.
6. The liquid hydrogen production apparatus according to claim 5, wherein the liquid hydrogen production device further comprises a second normal-para-hydrogen converter mounted on a pipe flowing from the first outlet to the first liquefaction tank, and the circulating hydrogen gas flowing into the first liquefaction tank through the second liquid discharge pipe is subjected to normal para-hydrogen conversion in the second normal-para-hydrogen converter.
7. The liquid hydrogen production apparatus according to any one of claims 4 to 6, wherein the liquid hydrogen production device further comprises a supercooling mechanism including a supercooler and a second liquefaction tank, the supercooler being installed in the second liquefaction tank, the first liquid discharge pipe being connected to the supercooler and the first liquefaction tank, medium-pressure liquid hydrogen flowing out of the first liquefaction tank flowing into the supercooler through the first liquid discharge pipe, the pipe mechanism further comprising a fourth pipe group including a third liquid discharge pipe and a return pipe, the third liquid discharge pipe being connected to the supercooler and a storage tank for storing liquid hydrogen, part of liquid hydrogen discharged from the supercooler entering the storage tank through the third liquid discharge pipe, the return pipe being connected to the third liquid discharge pipe and the second liquefaction tank, the fourth throttle valve being installed on the return pipe, part of liquid hydrogen discharged from the supercooler being input to the second liquefaction tank through the fourth throttle valve.
8. The liquid hydrogen production apparatus according to claim 7, wherein the fourth tube group further comprises a third exhaust tube, the first heat exchanger forms a second inlet and a second outlet, the third exhaust tube is connected to the second liquefaction tank and the second inlet, and low-pressure product hydrogen vaporized from the liquid hydrogen in the second liquefaction tank flows out through the third exhaust tube and enters the first heat exchanger through the second inlet and then is discharged from the second outlet.
9. The liquid hydrogen production apparatus according to claim 8, wherein the first heat exchanger includes a third inlet, the fourth tube group further includes a second cooling tube connected to the third liquid discharge tube and the third inlet, the valve group further includes a fifth throttle valve mounted to the second cooling tube, and a part of liquid hydrogen flowing out of the subcooler flows from the second cooling tube into the first heat exchanger through the fifth throttle valve and then is discharged from the second outlet.
10. A method of operating a liquid hydrogen production apparatus according to any one of claims 1 to 9, comprising: Raw material hydrogen enters the first heat exchanger through the raw material inlet, and one strand of circulating hydrogen entering the first heat exchanger exchanges heat with the raw material hydrogen entering the first heat exchanger and the other strand of circulating hydrogen entering the first heat exchanger; the raw material hydrogen after heat exchange is discharged from the first heat exchanger, enters the first normal-para-hydrogen converter through a pipeline and flows back to the first heat exchanger through a pipeline, normal-para-hydrogen conversion is carried out on the raw material hydrogen in the first normal-para-hydrogen converter, high-pressure product hydrogen is produced, and the high-pressure product hydrogen is discharged from the product hydrogen outlet; the circulating hydrogen which exchanges heat with the raw material hydrogen and heats up flows into the cooling mechanism and flows back to the first heat exchanger after the temperature is reduced, the circulating hydrogen which exchanges heat with the circulating hydrogen flowing through the cooling mechanism flows out of the first heat exchanger, is throttled by the second throttle valve from the pipeline, flows into the first heat exchanger, and exchanges heat with the raw material hydrogen.

Description

Liquid hydrogen production device and working method thereof Technical Field The application relates to the technical field of liquid hydrogen production, in particular to a liquid hydrogen production device and a working method thereof. Background Hydrogen energy is regarded as one of clean energy sources because of its pollution-free nature, however, the use of hydrogen energy requires a series of problems in preparation, storage, transportation, etc. For example, the produced compressed raw hydrogen gas needs to be subjected to pretreatment, normal para-hydrogen conversion and temperature reduction to be converted into liquid hydrogen for storage and transportation. However, the hydrogen molecule contains two spin isomers, respectively ortho and para, in a ratio of about 3:1 at ambient temperature. During the hydrogen temperature drop, normal hydrogen, which has a high energy state, spontaneously converts to para-hydrogen, which has a low energy state, and releases heat. During storage and transportation of liquid hydrogen, unconverted normal hydrogen will spontaneously convert to para-hydrogen and release heat, while liquid hydrogen will be heated to convert to the gas phase, resulting in evaporation of liquid hydrogen from the storage tanks and transport tanks, leading to impaired economic efficiency. In order to reduce loss, the existing liquid hydrogen production device sequentially introduces hydrogen into a plurality of normal para-hydrogen converters when producing hydrogen so as to produce hydrogen with para-hydrogen content reaching 95%, and in order to produce liquid hydrogen with higher para-hydrogen content, the raw material hydrogen needs to be reduced to a lower temperature, and a cooling medium exchanging heat with the raw material hydrogen needs to be reduced to a lower temperature, so that the energy consumption used by the whole production system is greatly improved, and the popularization and the use of hydrogen energy are not facilitated Disclosure of Invention To solve the above technical problems and to achieve at least one advantage of the present application, the present application provides a liquid hydrogen production apparatus including: A first heat exchanger forming a raw material inlet, a product hydrogen outlet, a first cooling medium inlet, a second cooling medium inlet, a first inlet and a first outlet, high-pressure raw material hydrogen enters the first heat exchanger through the raw material inlet, and high-pressure circulating hydrogen enters the first heat exchanger from the first cooling medium inlet and the first inlet respectively; a tube mechanism including a first tube group, a second tube group, and a first cooling tube, the first tube group, the second tube group, and the first cooling tube being connected to the first heat exchanger; The conversion mechanism comprises a plurality of first n-para-hydrogen converters, the first n-para-hydrogen converters are arranged on the first pipe group, raw material hydrogen is subjected to n-para-hydrogen conversion in the first n-para-hydrogen converters and high-pressure product hydrogen is produced, and the high-pressure product hydrogen is discharged from a product hydrogen outlet; The cooling mechanism comprises a plurality of expansion machines, the expansion machines are arranged on the second pipe group, and circulating hydrogen output by the second pipe group sequentially flows through the expansion machines and returns to the first heat exchanger; the valve bank comprises a second throttle valve, the second throttle valve is arranged on the first cooling pipe, the first cooling pipe is communicated with the first outlet and the second cooling medium inlet, and circulating hydrogen discharged from the first outlet flows back to the first heat exchanger from the second cooling medium inlet through the second throttle valve. According to an embodiment of the present application, the conversion mechanism includes four of the first normal-para-hydrogen converters, the four of the first normal-para-hydrogen converters being defined as a first converter, a second converter, a third converter, and a fourth converter in this order, and the first tube group includes a first intake tube, a first outlet tube, a second intake tube, a second outlet tube, a third intake tube, a third outlet tube, a fourth intake tube, and a fourth outlet tube; The first air inlet pipe and the first air outlet pipe are connected with the first converter and the first heat exchanger, raw material hydrogen entering the first heat exchanger from the raw material inlet exchanges heat with a cooling medium for the first time, then flows to the first converter through the first air outlet pipe, is converted into normal secondary hydrogen in the first converter, and then is input into the first heat exchanger through the first air inlet pipe to exchange heat with the cooling medium for the second time; The second air inlet pipe and the second air outl