Cryoconcentration unit CCU-6 (hereinafter referred to as CCU-6) is an integral part of an automated chromatographic complex based on a Crystallux -4000M gas chromatograph and is intended for quality control of helium 99,9999 and hydrogen 99,9999 for trace amounts of Ne, CH₄, O₂+Ar, N₂, CO, CO₂ и H₂.

CCU-6 concentrates gaseous impurities (Ne, H₂, O₂+Ar, CH₄, CO и СО₂) in helium and hydrogen in sorption columns at the temperature of liquid nitrogen, which are afterwards focused and desorbed and introduced into GC (equipped with FID-TCD and TCD- CCD detectors) to determine their qualitative and quantitative composition.

2.1.Test gas – helium, hydrogen

2.2. The temperature of the sorption columns during adsorption,ºС – -196

2.3. Maximum thermal desorption temperature, ºС – 400

2.4. Pressure of the analyzed gas, no more than MPa – 0,4

2.5. Inlet gas pressure, not more than MPa – 1,0

2.6. Total analysis time, no more than minutes – 17

2.7. The volume of the vessel with liquid nitrogen, l – 6

2.8. Automatic refill of liquid nitrogen before each concentration cycle

2.9. Power supply – 230-240В, 50-60Hz

2.10. Input power no more than, kW – 2000

2.11. Overall dimensions, mm – 510х600х1550

2.12. Weight, no more than kg –  30

This installation is an improved typ, it is made for the determination of trace elements not only in helium, but also in hydrogen.

In UKK-6, liquid nitrogen is added automatically, which minimizes the dangers of contact with such a dangerous substance.

The detection limits of the installation are shown in tables 1 and 2.

Table 1 Detection limits for helium analysis.

Table 2 Detection limits for hydrogen analysis