Argon purification unit

High purity argon purification equipment
I. overview
In order to improve the quality of silicon crystal, how to choose high purity argon is an issue of making silicon crystal. Through the use of this device, when the oxygen content of argon is less than 1ppm and the water content is less than 1ppm, the oxygen carbon content of the monocrystal silicon produced is less than 0.5ppm, which improves the service life of the monocrystal and can meet the requirements, and wins the satisfaction of customers and market demand.
The oxygen content of liquid argon is generally between 2ppm and 5ppm because it is not purified after vaporization. Sometimes the argon provided by the gas supplier exceeds this range, and the customers who use argon do not know its quality, so the quality of the products is often affected. No matter the quality of the argon feed gas, the purity of the argon entering the crystal furnace after the treatment of the purification device is always constant.
Generally, the oxygen content is less than 0.5ppm and the water content is less than 1ppm, so the stable argon gas can ensure the quality of the crystal.
2、 On the method of argon purification
The first direct deoxidation method is to use the active metal to react with the oxygen in the argon gas, digest the oxygen in the argon gas, so as to achieve the purpose of deoxidization, absorb the water in the argon gas through the molecular sieve, and make the water content of the argon gas less than 1ppm.
The second one is the use of getter. At a certain temperature, the getter can absorb nitrogen, hydrogen, oxygen, carbon monoxide, carbon dioxide, methane and other gases. After absorption treatment, the purity of argon can reach six nines. This protective gas is more suitable for making high-purity semiconductor monocrystalline silicon.
The purity of argon after purification by getter:
O2 less than 0.2ppm
H2 less than 0.5ppm
N2 less than 1ppm
CO+CO2≤0.5ppm
CH4 less than 0.5ppm
Water content ≤ 1ppm
In the first method, the investment of equipment is small, and the service life of deoxidizer in the equipment is generally more than two years.
In the second method, the purification purity of the equipment is high but the investment is relatively large, and the service life of the getter is one year.
Purpose:
A rare gas used as a shielding gas for arc welding (cutting) stainless steel, magnesium, aluminum, and other alloys. It is also used in the smelting of steel, aluminum, titanium and zirconium. Argon emits purple glow when discharging, and is also used in lighting technology and filling fluorescent lamp, photoelectric tube, lighting tube, etc.
In the process of brewing, the filler in the beer barrel can replace the oxygen to avoid the raw materials in the beer barrel being oxidized to acetic acid.
The heat treatment process is also used to replace nitrogen and ammonia, the effect is more than nitrogen and ammonia. When stainless steel is heat treated, the bending effect of argon protection is better and is not easy to fracture.