Method for first-time filling of gas of non-LNG pre-cooling ship

Abstract

The invention provides a method for first-time filling of gas of a non-LNG pre-cooling ship. A gas tank is arranged on the ship, and a pump pond and a liquid gasifier are included; the filling method comprises the following steps: S1, tank cooling, liquid nitrogen is injected into the liquid gasifier, the liquid gasifier gasifies liquid nitrogen into nitrogen at the temperature of -160 DEG C to -150 DEG C, and the nitrogen enters the gas tank through a pipeline to be subjected to tank cooling; S2, purging, the LNG is injected into the liquid gasifier, the liquid gasifier gasifies LNG into NG, the NG enters the gas tank through a pipeline to perform purging, and nitrogen in the gas tank is purged away; thirdly, filling, the LNG is injected into the pump pond, and transshipped to the gas tank through a pipeline to be subjected to filling. According to the method, operation is easy and effective, emissions of NG in the operation process can be reduced, the method is safe, and environment-friendly, resource waste is avoided, and shore station parking is avoided.

Description

technical field [0001] The invention relates to the field of first filling of ship gas, in particular to a method for first filling of non-LNG precooling ship gas. Background technique [0002] The temperature of liquefied natural gas (LNG) under normal pressure is -165°C. Generally, LNG ships and ships using LNG as fuel gas have liquid tanks for storing LNG, and the design temperature of the LNG maintenance system is generally -165°C. In the design stage, the stress calculation and analysis of the liquid tank and the corresponding liquid phase and gas phase piping systems are carried out according to the design pressure, so as to avoid damage caused by excessive stress in normal working conditions and when subjected to cold shock. Therefore, during the first filling process of ship gas The most critical process is cold canning. [0003] Under normal circumstances, the LNG storage tank of an LNG ship is also used as a gas tank. The LNG storage tank has been pre-cooled and ...

AI Technical Summary

Problems solved by technology

[0005] 1. The first refueling of gas by docking at the shore station has the following disadvantages: (1) The number of shore stations with qualifications for the first refueling of ship gas at home and abroad is small; (2) The time required for the first refueling of ship gas is relatively long It is difficult to be accepted by the shore station due to the limited schedule of the shore station; (3) the capacity of the gas tank is small, and the filling cost of the first refill at the shore station is relatively high

[0006] 2. Directly use LNG for cold tank filling without docking at the shore station. The disadvantage is that a large amount of NG gas will be discharged into the atmosphere for a long time during operation, and this operation has extremely high requirements on the surrounding environment of the filling site.

Using liquid nitrogen without docking at shore stations has obvious advantages in terms of safety and environmental protection compared to using LNG for cold tanks. However, due to the design temperature of the gas tank and its maintenance system is only -165°C, direct liquid nitrogen cannot be used. Nitrogen spray cold tank

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