A pre-cooling device before filling liquid helium storage tank

Abstract

The patent of the present invention discloses a precooling device before filling a liquid helium storage tank, which relates to the technical field of liquid helium storage tank precooling, including a liquid helium storage tank, a throttle valve, a cryogenic pump, a heat exchanger, a compressor, and a safety valve , injection device, liquid helium storage tank, density meter, one-way valve, second injection device, control unit and various stop valves, etc. The present invention adopts the method of "preliminary liquid hydrogen precooling + helium immersion precooling + liquid helium evaporation precooling". Reduced, process economic benefits improved. The invention adopts the method of helium soaking and precooling to further cool the liquid helium storage tank, liquefy the residual hydrogen and discharge it, and ensure the purity of the product quality is qualified. Heat rate, reduce pre-cooling time.

Description

technical field [0001] The invention relates to the technical field of precooling of a liquid helium storage tank, in particular to a precooling device before filling a liquid helium storage tank. Background technique [0002] Helium has an extremely low boiling point (4.2K), critical temperature (5.15K) and critical pressure (0.226MPa), which can easily achieve ultra-low temperature cooling that cannot be achieved by other cryogenic liquids, so it is used in aerospace, nuclear weapons, submarines, and saturation diving operations , nuclear magnetic resonance, semiconductor and other scientific and technological fields have played an irreplaceable role. At present, my country's annual demand for helium exceeds 2.2×10 7 m 3 , but my country only has one in Sichuan with an annual output of 6×10 4 m 3 Helium extraction plants in Hetianhe Gas Field and Ake Gas Field are still under construction. Almost all helium supply depends on imports, and the international helium market...

AI Technical Summary

Problems solved by technology

However, these methods have not penetrated into the liquid helium temperature zone. If they are directly applied to the precooling of liquid helium storage tanks, there will be the following problems: (1) As liquid helium is currently the natural resource with the lowest boiling point, it is difficult to find a low boiling point. The low-temperature working fluid of liquid helium directly precools the storage tank to the liquid helium temperature zone; (2) if the storage tank is directly pre-cooled by using liquid helium as the cold source, it will face the problems of large consumption of liquid helium resources and high price. Even if the method of circulating precooling is adopted, it is restricted by the capacity of the helium liquefaction device of the natural gas helium extraction plant, and the time cost is huge; (3) if the method of precooling liquid helium and other cryogenic working fluids is used, considering the quality of the liquid helium product The purity requirement is extremely high. How to ensure that the residual amount of other low-temperature working fluids in the storage tank will not affect the quality of the externally infused liquid helium product is a problem that must be faced by this method.

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