Liquefied natural gas storage tank BOG recovery system

Abstract

The invention discloses a liquefied natural gas storage tank BOG recovery system. The system comprises a natural gas purification tower, an air cooler, a purified natural gas precooling heat exchangerand a gas generator. A raw natural gas is connected with the natural gas purification tower through a pipeline, the natural gas purification tower is connected with the purified natural gas pre-cooling heat exchanger for pre-cooling a purified natural gas through the pipeline, and the purified natural gas pre-cooling heat exchanger conveys the gas to a cold box for cryogenic treatment through thepipeline to form a purification system. A cold source of the purified natural gas pre-cooling heat exchanger is BOG, the natural gas purification tower is connected with an air cooler of a regenerated gas, the air cooler conveys the BOG used as the regenerated gas to the gas generator to form a regeneration system, and valves are arranged on all connected pipelines. In the invention, switching between operation and regeneration of the natural gas purification tower is realized through the pipelines and the valves, and problems of resource waste, environmental pollution and potential risks caused by a fact that overpressure BOG released in a storage process of the storage tank is directly released into air are solved.

Description

technical field [0001] The invention relates to the technical field of natural gas, in particular to a BOG recovery system for a liquefied natural gas storage tank. Background technique [0002] In recent years, environmental pollution has attracted more and more attention from the public and the government, and LNG has been recognized by people for its environmental protection and cleanliness. In the rapid development of LNG liquefaction plants, in order to ensure the safety of the system, most of the overpressured BOG and the BOG (Boil Off Gas flash steam) unloaded and unloaded are directly released. BOG itself is a very Discharging clean fuel into the air is not only an unnecessary waste, but also flammable gas is discharged into the air, which has potential risks and brings economic losses to the owners. The main component of BOG is methane, which is a gas with a strong greenhouse effect. If it is discharged into the atmosphere, its greenhouse effect is 21 times that o...

AI Technical Summary

Problems solved by technology

In the rapid development of LNG liquefaction plants, in order to ensure the safety of the system, most of the overpressured BOG and the BOG (Boil Off Gas flash steam) unloaded and unloaded are directly released. BOG itself is a very Discharging clean fuel into the air is not only an unnecessary waste, but also flammable gas is discharged into the air, which has potential risks and brings economic losses to the owners

Images