Reliable, trouble-free melt filtration as a decisive factor for the economical use of reclaim in plastics processing

Reliable, trouble-free melt filtration as a decisive factor for the economical use of reclaim in plastics processing

December 9, 2020 Off By Sebastian Reisig

If inhouse waste and heavily contaminated post-consumer waste are added to the production process, foreign particles of various sizes and quantities are introduced into the melt flow. These have to be filtered out efficiently to ensure a consistent and high quality of the end product. At the same time, however, melt filtration must not have any disturbing influence on the production process.

Several filtration systems require a production interruption when changing screens, cause process disturbances due to pressure spikes or even generate particles if deposited material comes off during screen changes.

Disturbance-free production process thanks to permanently constant conditions

In contrast, with the unique Gneuss Rotary Technology, the conditions in the melt flow are permanently constant, i.e. the pressure drop across the screen, respectively the amount of contamination on the screen, is kept constant, so that the line can always be operated in the optimum range.

This is achieved by the rotating movement of the filter disk, with which the screens are transported through the melt channel. A control system ensures that the screen contamination remains constant. As soon as the contamination load varies, the control system reacts automatically and changes the rotational speed of the filter disk. The pressure across the system thus remains constant, the only non-constant variable in the filtration process is the rotational speed of the filter disk.

This makes the Rotary Technology the ideal solution for the increased use of reclaim or recycled material. Gneuss Melt Filtration Systems can be easily integrated into an existing process and are perfectly suited as a retrofit solution. The self-sufficient control system monitors the filtration process in conjunction with the production line.

Advantages of Gneuss Filtration Systems for recycling applications

The Gneuss Filtration Systems have been developed for demanding recycling applications and have been used successfully for decades. All filters from the technology leader in Bad Oeynhausen, Germany, work with the proven and unique Rotary Technology, which offers the following advantages:

  • No interruption or disturbance of the production process caused by the filter operation
  • Pressure-constant production, free from pressure spikes
  • Automatic and safe operation with minimal operating effort
  • Application-specific and rheologically optimised melt channel for short melt residence times, melt channel design free from dead spots and fast product changes
  • Disturbance-free processing even of sensitive plastics
  • Consistently high quality of the end product
  • Simple and safe filter element replacement
  • Efficient cleaning of the filter elements thanks to the fully automatic back-flushing Filtration System Type RSFgenius
  • Screens made of multi-layer stainless steel mesh, which allows finenesses down to 10 µm in recycling applications
  • For more than 35 years successful use in film, sheet and fiber production, compounding, PVC and other demanding applications