Nitrogen-Condensation-System
- Two small liquefaction systems in the background are able to produce about 6 liters of liquid nitrogen per hour. The large system in front is capablem to produce more than 30 liters per hour.
- Large nitrogen liquefaction system.
Motivation:
In scientific research liquid nitrogen is necessary as a cooling medium to reach low temperatures. N2 condensates at a temperature of 77,35 K. It is easy to extract nitrogen from air, therefore it is preferred for cooling at temperatures above 77K, instead of using expensive helium. In this way high-temperature superconductors can be cooled with a sensible expenditure.
The II. Institute of Physics of the RWTH Aachen University operates a nitrogen liquefaction system, that extracts the nitrogen of the air. So it is possible to abstrain from buying nitrogen on the open market.
Liquefaction:
The liquefaction system is capable to produce 42 liters of nitrogen per hour. The cooling proceeds in two steps. In the first step the nitrogen is seperated from the oxygen by using the different evaporation temperatures. In the second step the remaining nitrogen is condensated and stored in 500 and 1000 liter dewars. The helium liquefaction system is connected via a transfer tube to the liquid nitrogen dewars on order to precool the helium gas.