Method and system for preparing high purity gas by rectification method

Abstract

The invention relates to a method and a system for preparing high purity gas by a rectification method. According to the method disclosed by the invention, a target gas raw material is firstly processed by a light component removal tower to remove light component impurities and then is processed by a heavy component removal tower to remove heavy component impurities; obtained purified gas is compressed into compressed gas; the compressed gas is at least divided into two parts which are respectively used as heat sources of a tower kettle reboiler of the light component removal tower and a tower kettle reboiler of the heavy component removal tower; the two parts of compressed gas are condensated into liquid to be converged and stored; the stored liquid is divided into three parts; two parts of the stored liquid are respectively used as a cooling medium of a tower top condenser of the light component removal tower and reflux of the heavy component removal tower after being respectively subjected to throttling expansion; and the third part of the stored liquid is recovered as a product. The system disclosed by the invention comprises the light component removal tower, the tower top condenser of the light component removal tower, the heavy component removal tower, a compressor, the tower kettle reboiler of the light component removal tower, the tower kettle reboiler of the heavy component removal tower, a liquid storage tank and a connecting pipeline. The method and the system which are disclosed by the invention have the advantages that equipment is simple; energy is saved; the method and the system are flexible to operate and have wide application; the system is easy to maintain; and the method and the system have few requirements on public works.

Description

technical field [0001] The invention relates to a method and system for preparing high-purity gas by rectification. Background technique [0002] High-purity gas usually refers to a gas that has been purified to a certain level of purity by means of purification technology. For different gases and their applications, the purity requirements are different. Generally speaking, the purity of high-purity gas is above 3.0N (99.9%), and the purity of high-purity gas used in the electronics industry is generally required to be above 5.0N (99.999%). High-purity gases have been widely used in many industrial fields. [0003] High-purity gases are usually produced by deep purification of the gas feedstock. In the prior art, for different types of gases, it is necessary to adopt different methods according to the physical and chemical properties of the gases and the impurities contained in them. Generally, adsorption methods, reaction methods, rectification methods or several of the ...

AI Technical Summary

Problems solved by technology

[0005] (1) Both the light removal system and the weight removal system of this technology require tower top condenser equipment and corresponding energy, as well as independent compressor equipment and corresponding energy, so the equipment and energy consumption are still relatively large;

[0006] (2) The light removal system and the weight removal system independently apply heat pump rectification technology. In each system, after compression, the flow rate of the material exchanged between the reboiler of the tower and the liquid in the tower tank is the same as that obtained by throttling and decompression. The quantity is completely equal, so the realization of system heat and material balance requires very strict parameter setting, the operating pressure and flow adjustment flexibility of the system is poor, and the system adjustment is limited;

Images