While the MRS extruder operates with the low-maintenance 25 mbar liquid pump system as standard, special effects can be achieved by combining the extruder‘s intensive surface exchange with a lower vacuum (e.g. 1 mbar). During the degassing process on the high-performance OMNImax and OMNIboost recycling systems, in addition to water vapour and ethylene glycol, a large amount of monomers, dimers, waxes or other sticky substances are extracted which quickly block the conventional, closely intermeshing vacuum generation systems. The focus must therefore be on separating these substances between the degassing dome and the vacuum generator. Gneuss has developed vacuum technologies that are optimally adapted to the respective processes.

During degassing, a large proportion of the gases consists of water vapour, sometimes up to 1 % of the throughput and more. For a 1000 kg/h system this means 10 l/h of water or 10 m³/h of water vapour (under standard conditions) to be extracted. With a lower vacuum, this gives a theoretical suction capacity of 10,000 m³/h, which would require a very large system size. For this reason, robust cold trap technology is used for vacuum degassing. This is cooled by a very cold circulating medium so that the extracted water vapour passes into the solid phase (resublimation).

The ice deposited on the heat transfer surfaces (as well as any other products that are also removed) can then be removed by either mechanical cleaning during the process or by thawing. The reduced pumping volume, consisting of residual gas and any polymer filaments or droplets due to high flow velocities, is then passed through a safety filter before the residual gas flow is fed to the pumps.
The use of sublimators in Gneuss vacuum technology drastically reduces pump volume, allowing the use of smaller pumps and lower energy consumption. It also increases the reliability of the vacuum generators used.