After a 2-year R&D phase, the research project approved by the Federal Ministry for Economic Affairs and Energy was completed in October 2018 with the result of a new "cryogenic gas evaporator system".
The aim of the project was to make the cooling energy released by the vaporization of nitrogen (enthalpy gain) available to consumers as useful cooling by means of a nitrogen vaporization plant to be developed.
When 1 kg of liquid nitrogen (8 bar, -172.5°C) is evaporated to normal pressure and 5°C, there is an enthalpy difference of 359 kJ, which can now be utilized as cooling energy with our system.
The difficulty in developing this system was that common heat carriers such as water, water-glycol mixtures and pure glycol solidify at these low temperatures and can therefore no longer be pumped or conveyed.
A suitable heat exchanger apparatus and arrangement was therefore developed, which is then controlled and monitored via the sensors and software.
Text: K. Uitz
Photo: SIMAKA