Device system for purifying by utilizing gas separation membrane

Abstract

The invention discloses a device system for purifying by utilizing a gas separation membrane. The device system comprises a mixing device, a pretreatment unit and three gas separation membrane units, wherein two ends of the mixing device are respectively communicated with a raw material gas and the pretreatment unit; a gas passes through the pretreatment unit and enters a gas inlet of the first gas separation membrane unit; an impermeable gas of the first gas separation membrane unit is communicated with a gas inlet of the second separation membrane unit; impermeable gases of the first and second gas separation membrane units pass through a mixed flow tank, and are communicated with a gas inlet of the third separation membrane unit; an impermeable gas outlet of the third separation membrane unit is provided with a backpressure control valve, and is communicated with a gas inlet of the mixing device for cyclic purification; the impermeable gas of the second separation membrane unit is a tail gas; the permeable gas of the third separation membrane unit is a product gas. According to the invention, three membrane units are used for purifying independently so as to completely purify gases, such as helium, hydrogen, carbon dioxide, and the recycling rate is relatively high; the device system is simple and compact in structure, and is applied to industrial production.

Description

technical field [0001] The invention relates to gas purification, in particular to a device system using gas separation membranes for purification. Background technique [0002] Helium is one of the rare strategic materials indispensable for the development of national defense industry and high-tech industry. Helium-containing natural gas is still the only source of industrial production of helium so far. my country's helium resources are quite poor, the content is very low, the extraction is difficult and the cost is high. Therefore, the research and development of advanced natural gas helium extraction technology, as well as the purification and recovery of helium used in process production, are of great significance for improving the economy of helium production, ensuring the safety of national helium use, and promoting the development of my country's natural gas helium extraction industry. [0003] The current helium purification process mainly includes pressure swing ...

AI Technical Summary

Problems solved by technology

[0007] Prior art such as patent document CN203874647U discloses a membrane method helium purification device system and patent document CN104001409A discloses a membrane method helium purification device system and process, both patents have adopted membrane separation technology, but their devices The system only has the first-stage hollow fiber membrane and the second-stage hollow fiber membrane. This two-stage separation membrane system may not be able to achieve sufficient purification of helium, and thus cannot obtain high-purity helium; in addition, the two patents are in There is a compressor between the first-stage hollow fiber membrane and the second-stage hollow fiber membrane, which makes the whole purification system complicated and may also increase the operating cost of the system

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