A method for removing oxygen and nitrogen, separating and purifying neon and helium

Abstract

The invention provides a method for removing oxygen and nitrogen and separating and purifying neon and helium. The specific process is: the mixed raw material gas of oxygen, nitrogen, neon and helium after dehydrogenation and drying treatment is pressurized into a low-temperature cold box for cooling, and is removed by low-temperature condensation and low-temperature adsorption. Oxygen, nitrogen and other impurities in the raw material gas, the obtained pure neon-helium mixture continues to cool down and is separated by low-temperature condensation and low-temperature rectification to obtain high-purity neon. And cryogenic freezing to remove neon gas and obtain high-purity helium gas. The invention mainly adopts low-temperature refrigerator and liquid nitrogen as cold source, which can provide stable cooling capacity for the system, and the operating pressure of the system is low, and the process is simplified on the basis of satisfying the function realization. The low-temperature adsorption involved in the method, in the adsorption After saturation, the adsorbed gas can be recovered. This method greatly improves the utilization rate of raw material gas and is suitable for large-scale industrial production.

Description

technical field [0001] The invention relates to a method for separating and purifying helium-neon gas, in particular to a method for removing oxygen and nitrogen and separating and purifying neon-helium. Background technique [0002] Neon and helium are rare inert gases, which are very important in high-end fields such as nuclear magnetic resonance, optical fiber, submarine, aviation, aerospace, scientific research and nuclear weapons. [0003] Helium is a non-renewable limited resource, which is mainly separated and purified from helium-rich natural gas. The helium resources of the United States account for more than 50% of the world, plus the helium resources it controls in the Middle East and other regions, more than 90% of the helium resources in the world are controlled by the United States, and have been listed as strategic resources. [0004] Neon gas is also a rare gas. At present, the output of neon gas in the world is about 375 million liters, and these products a...

AI Technical Summary

Problems solved by technology

Especially in recent years, due to changes in the market environment, the price of neon gas has risen sharply, which has brought great challenges to domestic production and research.

[0005] In the industry, neon and helium are mainly extracted from the air separation unit, usually using low-temperature condensation and low-temperature adsorption methods, mainly using liquid nitrogen, liquid neon, and liquid hydrogen as cold sources for low-temperature condensation and low-temperature adsorption. This traditional method and the corresponding The technological process leads to complex equipment and requires high operating pressure. During the operation, the temperature, flow control and system cooling supply stability are poor, and the purity of the obtained gas is low.

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