LNG transport ship BOG treatment system and method using nitrogen and helium expansion process

Abstract

The invention relates to an LNG transport ship BOG treatment system and method using a nitrogen and helium expansion process. The system comprises the following components: an LNG storage cabin and a cold box, wherein a liquid phase outlet of the LNG storage cabin is connected with a first inlet of the cold box, and a first outlet of the cold box is connected with a spraying pipeline at the top of the LNG storage cabin; and an expansion machine, a compressor and a cooler, wherein an inlet of the expansion machine is connected with a second outlet of the cold box, an outlet of the expansion machine is connected with a third inlet of the cold box, a third outlet of the cold box is connected with a fourth inlet of the cold box, a fourth outlet of the cold box is connected with an inlet of the compressor, an outlet of the compressor is connected with an inlet of the cooler, and an outlet of the cooler is connected with a second inlet of the cold box. The treatment system preferably further comprises an LNG immersed pump, the LNG immersed pump is arranged in the LNG storage bin, and the LNG immersed pump is configured to convey LNG in the LNG storage bin to the cold box. The system is integrally formed and is easy to arrange and mount.

Description

technical field [0001] The invention relates to a BOG treatment system and method of an LNG carrier using a nitrogen and helium expansion process, and belongs to the field of BOG recovery and treatment of an LNG carrier. Background technique [0002] During the storage and transportation of natural gas, since the storage container of liquefied natural gas (LNG) cannot be completely insulated, Boil Off Gas (BOG) will be generated during storage and transportation. If these excess BOG cannot be dealt with in time, the pressure in the cargo hold of the ship will be rapidly increased, which will bring great danger to the operation of the ship. Compared with burning these excess BOG, the reliquefaction unit can not only recover, but also reduce the temperature of the cargo hold and reduce the harsh conditions for the selection of the propulsion system. At present, mainstream large-scale LNG transport ships and LNG bunkering ships prefer to be equipped with BOG reliquefaction dev...

AI Technical Summary

Problems solved by technology

If these excess BOG cannot be dealt with in time, the pressure in the cargo hold of the ship will be rapidly increased, which will bring great danger to the operation of the ship

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