CN-121990147-A - System for liquid hydrogen ship adopts methyl alcohol to prepare and handles surplus evaporation gas

Abstract

The invention belongs to the technical field of ships and provides a system for preparing and treating surplus evaporating gas by adopting methanol in a liquid hydrogen ship. According to the invention, excessive BOG of the liquid hydrogen ship is reacted with CO 2 to prepare and store methanol in the stormy weather or in a maneuvering navigation process, and when the BOG amount in the normal navigation process of the ship cannot meet the requirement of a host, the methanol is used as fuel for the ship, so that the cost of the ship for preparing the BOG reliquefaction device is saved, the problem of excessive BOG of the liquid hydrogen ship is effectively solved, meanwhile, part of CO 2 is loaded on the liquid hydrogen ship, and the CO 2 in the C-type tank is kept cool by utilizing cold energy generated by the liquid hydrogen for the host, so that the generation of the BOG of CO 2 is reduced, the cold energy of the liquid hydrogen is reasonably utilized, and the method has good innovation.

Inventors

• LI BOYANG
• ZHANG SHUHAO
• ZHUANG CHENG
• YANG HUALIN
• CHEN HAIZHOU
• ZHANG NI

Assignees

• 青岛科技大学

Dates

Publication Date

20260508

Application Date

20260130

Claims (5)

1. 1. A system for preparing and treating surplus evaporating gas by using methanol in a liquid hydrogen ship is characterized by comprising a hydrogen fuel supply system, a methanol preparation system, a methanol supply system and a CO 2 cold insulation system, The methanol preparation system comprises a liquid hydrogen tank (1), a compressor (2), a BOG valve (12), a methanol preparation unit (15), a C-type tank (13), a CO 2 pump (14) and a methanol tank (16), The CO 2 pump (14) is arranged at the bottom of the C-shaped tank (13) and is connected with the methanol preparation unit (15) through a pipeline, the liquid hydrogen tank (1) is connected with the compressor (2), the BOG valve (12) and the methanol preparation unit (15) in sequence through pipelines, the methanol preparation unit (15) is connected with the methanol tank (16) through a pipeline, The CO 2 cold insulation system comprises a liquid hydrogen tank (1), a compressor (2), a heat exchanger (4), a circulating pump (11) and a C-type tank (13), The liquid hydrogen tank (1) is sequentially connected with the compressor (2) and the heat exchanger (4) through pipelines, and the heat exchanger (4) is sequentially connected with the circulating pump (11) and the C-shaped tank (13) through pipelines.
2. 2. The system for treating excess boil-off gas by methanol production of a liquid hydrogen vessel according to claim 1, wherein the engine block comprises 3 hydrogen fuel engines (7) and 1 methanol fuel engine (20), and the hydrogen fuel engines (7) and the methanol fuel engines (20) are dual-fuel engines.
3. 3. A system for treating surplus boil-off gas by methanol production according to claim 1, wherein the C-tank (13) is placed on the rear deck of the tail building of the ship.
4. 4. A system for treating surplus boil-off gas by methanol production according to claim 1, wherein the methanol tank (16) is placed under the deck at the stern.
5. 5. A system for treating surplus boil-off gas by methanol production in a liquid hydrogen vessel according to claim 1, wherein the methanol production unit (15) is placed on the rear deck of the vessel tail building.

Description

System for liquid hydrogen ship adopts methyl alcohol to prepare and handles surplus evaporation gas Technical Field The invention belongs to the technical field of ships, and particularly relates to a system for preparing and treating surplus evaporation gas by adopting methanol in a liquid hydrogen ship Background With the shift of energy structures to clean and low-carbon, the global demand for clean fuel is increasing, and the number of liquid hydrogen carriers (liquid hydrogen carriers for short) in the future is increasing. In order to increase the transport amount of hydrogen, hydrogen is generally stored in a cargo tank in a liquid state for transport. The storage temperature of liquid hydrogen is usually around minus 253 ℃ and has a great temperature difference from the outside air temperature, so that even if good heat preservation measures are adopted, vaporization gas (BOG for short) of liquid hydrogen is inevitably generated. Because the BOG is hydrogen, the BOG is a clean energy source with high heat value and no pollution, and is usually burnt in the course of navigation. In the sailing process of the liquid hydrogen ship, when the weather is good (sea condition is good), the sailing speed of the liquid hydrogen ship is faster (about 19 knots), at the moment, the power of a ship main engine (a dual-fuel engine) is high (the power of the ship main engine is in direct proportion to the 3 rd power of the sailing speed), and the generated BOG can be completely burnt by the ship main engine. When the BOG production cannot meet the demand of the ship host, part of the liquid hydrogen needs to be vaporized so as to obtain enough BOG for the ship host to burn. When the ship encounters stormy waves or maneuvers, the navigational speed is greatly reduced, the BOG burning amount of the main engine of the ship is greatly reduced, and the liquid hydrogen has low density, the draft is shallow when the liquid hydrogen ship is fully loaded, the ship body shakes violently when the stormy waves, and the mechanical energy generated by the liquid hydrogen in the liquid hydrogen tank in the shaking process is partially converted into heat energy, so that the BOG generating amount is further increased. For the two reasons, the phenomenon that BOG is excessive (namely, the main engine of the ship cannot completely burn the liquid hydrogen evaporation gas) occurs in the process of stormy days or maneuvering navigation. The above-mentioned is the processing mode of BOG that the liquid hydrogen ship produced in the navigation process, and the processing mode of liquid hydrogen ship to surplus BOG is to store in the liquid hydrogen tank after liquefying through reliquefaction device, but because the storage temperature of liquid hydrogen is extremely low, the requirement on the liquefaction device is very high to the equipment cost and the running cost of device are very high, consequently to the reliquefaction cost of BOG very big. Because of the obvious disadvantages of this way, the reasonable disposal of excess BOG is a technical problem to be solved by liquid hydrogen vessels. At present, the technology for preparing the methanol by adopting the CO 2 and the hydrogen is very mature, the preparation process is simple, the cost is low, the prepared methanol is a clean fuel, the methanol is in a liquid state at normal temperature and normal pressure, the storage and transportation are convenient, and the methanol is a clean fuel which is ideal for ships. Because of the global improvement of carbon emission requirements, the CO 2 emitted by ships and factories needs to be provided with a carbon capture device to capture the CO 2 emitted by the ships and factories and is transported to a port for centralized unloading, which leads to an increasing reserve of CO 2, and the port cannot utilize so much CO 2, so that a large amount of 'CO 2 garbage' exists in the port in the future, the port needs to be transported to a designated place for deep sea storage through a CO 2 transport ship, and the storage cost is very high, so that the acquisition of CO 2 in the port in the future is very easy. Based on the problems, the invention provides a system for preparing and treating surplus evaporating gas by using methanol in a liquid hydrogen ship, which is used for preparing methanol by utilizing surplus BOG to react with CO 2 in stormy days or in maneuvering navigation, and storing the prepared methanol in a cargo hold, when the navigation speed of the ship is higher, the BOG amount can not meet the requirements of a host, the methanol is used as fuel for the ship, the problem of surplus BOG in the navigation process of the liquid hydrogen ship is reasonably solved, and the system has good innovativeness and practical value. Disclosure of Invention The invention aims to solve the problem of treatment of surplus boil-off gas of a liquid hydrogen ship, and provides a system for treating the surplus boil-off gas by adopting methano