Method and apparatus for cryogenic separation of air

By designing a three-tower system and a condenser-evaporator, the problem of existing equipment being unable to efficiently produce high-purity nitrogen and impure oxygen has been solved, achieving efficient air separation and meeting the needs of semiconductor and display manufacturing.

CN115151771BActive Publication Date: 2026-07-24LINDE AG
View PDF 6 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
LINDE AG
Filing Date
2021-03-05
Publication Date
2026-07-24

AI Technical Summary

Technical Problem

Existing air separation equipment is unable to efficiently provide relatively large amounts of high-purity nitrogen and a certain amount of impure oxygen, which cannot meet the needs of fields such as semiconductor manufacturing and display manufacturing.

Method used

A three-tower system is adopted, including a high-pressure tower, a low-pressure tower, and an additional third distillation tower. By adjusting the pressure levels of each tower and the design of the condenser and evaporator, the pressure of nitrogen products is increased, and impure oxygen is extracted in the third distillation tower. Efficient separation is achieved by using an expander and a condenser and evaporator.

Benefits of technology

It has achieved efficient air separation for the production of high-purity nitrogen and impure oxygen, improving production efficiency and meeting the needs of fields such as semiconductor and display manufacturing.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN115151771B_ABST
    Figure CN115151771B_ABST
Patent Text Reader

Abstract

This invention relates to a method for cryogenic air separation, wherein an air separation apparatus (100-400) having a first distillation column (11) and a second distillation column (12) is used, wherein cooled compressed air is supplied to the first distillation column (11), and liquid from or formed therefrom the first distillation column (11) is supplied to the second distillation column (12). The top gas of the first distillation column (11) is condensed by means of a first condenser evaporator (111), and the liquid from or formed therefrom of the second distillation column (12) is evaporated to obtain a first evaporation product. The top gas of the second distillation column (11) is condensed by means of a second condenser evaporator (121), and a further liquid from or formed therefrom of the second distillation column (12) is evaporated to obtain a second evaporation product. A first portion of the second evaporation product is expanded, heated, and removed from the method by means of an expander (7). The top gas of the first distillation column (11) is removed from the method as a pure nitrogen product. The method involves using a third distillation column (13), condensing a second portion of the second evaporation product using a third condenser evaporator (131), and evaporating the liquid from or formed therefrom in the third distillation column (13) to obtain a third evaporation product; at least a portion of the second portion of the second evaporation product condensed using the third condenser evaporator (131) is fed to the third distillation column (13); further unevaporated liquid from or formed therefrom in the second distillation column (12) is supplied to the third distillation column (13); and the further bottom liquid from or formed therefrom in the third distillation column (13) is internally compressed and removed from the method as an impure oxygen product. The invention also relates to a corresponding air separation device (10CM00).
Need to check novelty before this filing date? Find Prior Art

Citation Information

Patent Citations

  • Multistoreyed bath condenser

    EP1287302B1

  • Method for the low-temperature decomposition of air and air separation plant

    EP2789958A1

  • Method and device for generating compressed nitrogen by the cryogenic decomposition of air

    EP3521739A1

  • Method for the low-temperature decomposition of air and air separation plant

    EP3557166A1

  • Air separation device and air separation method

    CN105910388A