Helium low-temperature purification method and device and helium refrigeration cycle system

Abstract

The invention discloses a helium low-temperature purification method and device and a helium refrigeration cycle system. The method comprises the steps of preparation before purification; pre-cooling; and purifying. The device comprises a pipeline system, a precooling heat exchanger, a low-temperature heat exchanger, a purifier, a Dewar tank, a vacuum pump and a helium tank group; a purification pipeline and a vacuum pipeline are arranged in the pipeline system, inlet stop valves are arranged on inlet pipe sections of the purification pipeline and the vacuum pipeline, outlets of the purification pipeline and the vacuum pipeline are converged on an outlet pipeline of the pipeline system, and an outlet stop valve is arranged on the outlet pipeline; the pre-cooling heat exchanger, the low-temperature heat exchanger and the purifier are sequentially in communication and mounted on the purification pipeline and are all packaged in the Dewar tank; the vacuum pump communicates with an inlet of the vacuum pipeline; and the helium tank group is in communication with an inlet of the purification pipeline. According to the helium low-temperature purification method and device provided by the invention, high-purity helium with the purity of 6N can be produced, and application occasions with high-purity requirements, such as the helium refrigeration cycle system and the like, can be met.

Description

technical field [0001] The application belongs to the technical field of chemical gas separation, and in particular relates to a helium low-temperature purification method and device, and a helium refrigeration cycle system. Background technique [0002] The nitrogen removal and neon-helium separation processes in the neon-helium extraction device occur at low temperature, and the cooling capacity is provided by the helium refrigeration cycle system, and the final cooling temperature needs to reach 24K. The helium required by the helium refrigeration cycle system at the initial stage of operation is all from the external helium raw material gas, which still contains traces of neon, oxygen, nitrogen, and water with impurity concentrations of PPM (parts per million concentration). The flat expander is small in size, only the size of a bottle cap, and is very precise. Impurities freezing in an ultra-low temperature environment will damage the blades of the expander, resulting i...

AI Technical Summary

Problems solved by technology

The helium required by the helium refrigeration cycle system at the initial stage of operation is all from the external helium raw material gas, and still contains traces of neon, oxygen, nitrogen, and water with impurity concentrations of PPM (parts per million concentration). The flat expander is small in size, only the size of a bottle cap, and is very precise. Impurities freezing in an ultra-low temperature environment will damage the blades of the expander, resulting in a significant decline in the performance of the entire low-temperature system

[0003] Existing helium low-temperature purification methods or helium low-temperature purification devices can only produce helium with a purity of 5N (purity above 99.999%), which cannot meet high-purity requirements such as helium refrigeration cycle systems

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