1LPH liquid nitrogen generator

The QLLPLN series liquid nitrogen system is a device that produces the nitrogen required by the customer through the PSA nitrogen generator, and then liquefies it through a nitrogen liquefier, and finally produces liquid nitrogen.

The PSA nitrogen generator uses high-quality carbon molecular sieve as the adsorbent according to the principle of pressure swing adsorption, and produces nitrogen from the air under a certain pressure. The purified and dried compressed air is subjected to pressure adsorption and decompression desorption in the adsorber. Due to the kinetic effect, the diffusion rate of oxygen in the micropores of the carbon molecular sieve is much greater than that of nitrogen. When the adsorption does not reach equilibrium, nitrogen is enriched in the gas phase to form finished nitrogen. Then the pressure is reduced to normal pressure, and the adsorbent desorbs the adsorbed oxygen and other impurities to realize regeneration. Generally, two adsorption towers are installed in the system. One tower absorbs nitrogen and the other tower desorption and regeneration. The two towers are automatically controlled by PLC program to make the two towers work alternately.

Nitrogen liquefier is a cryogenic mixed working fluid throttling refrigerator driven by a single compressor with precooling to achieve the requirement of nitrogen liquefaction (-180℃). The cryogenic mixed working fluid throttling refrigerator is based on a regenerative multi-mixed working fluid throttling refrigeration cycle. From ambient temperature to target refrigeration temperature, high, middle and low boiling point pure components are selected to form multiple mixed working fluids to achieve each boiling point component The relay matching of the effective cooling temperature zone is a refrigerator that can efficiently realize the temperature zone of -40~-196℃.

Liquid nitrogen plant process flow chart