OMNI

Gneuss’ MRS Extrusion Technology has proven itself as an alternative for the reprocessing of contaminated materials like polyester, nylon, polystyrene, polypropylene or other polymers. In combination with the highly efficient Gneuss Rotary Filtration Systems and optimized vacuum technology, customizable recycling lines tailor-made for a specific material can be engineered. Several Letters of Non Objection (LNOs) from the FDA, EFSA conformity and local approvals in Latin America confirm the decontamination efficiency of the technology.

3C Rotary Feeder

The newly developed 3C Rotary Feeder makes it possible to use low bulk density materials without any external processing steps. A conveyor belt feeds shredded reclaim material into the hopper, where a fast-rotating disc with knives cuts, compacts and pre-conditions the material. The knives add energy into the material and start the heating and degassing process before the material is automatically fed into the  extrusion system.

MRS extruder

The MRS extruder is based on the conventional single screw extruder, but is equipped with a multiple screw section, for optimum devolatilisation. The polymer melt is delivered into a large single screw drum. The drum contains 8 small extruder barrels, parallel to the main screw axis. Installed in these small extruder barrels are the “satellite” screws, which are driven by a ring gear in the main barrel. The satellite screws rotate in the opposite direction to the main screw while they rotate around the screw axis. This disproportionately increases the surface exchange of the polymer melt. So that the volatiles can be freely evacuated, the MRS extruder is equipped with a large opening for venting (exposing the full length of the satellite screws) which is completely under vacuum. This provides excellent and unrestricted access to the polymer melt, the surface of which is constantly replaced at an extremely high rate by the action of the satellite screws in the multiple screw section. Further, precise control of the melt temperature is possible as the temperatures of all the surfaces in contact with the melt can be controlled accurately.

RSFgenius

Gneuss’ top model, the RSFgenius, operates with an integrated back-flushing system offering self-cleaning for very demanding applications and highest quality requirements. Screens can be automatically re-used up to 400 times, and filtration finenesses below 10 microns/1200 mesh are available.

Vacuum technology

In order to be able to extract volatile impurities, Gneuss has developed specialized vacuum systems, some of which have patented separation systems. Due to the large melt surface in the extruder, the suction capacity is much higher than with conventional systems, so that large quantities of volatile impurities can be extracted from the polymer melt and separated from the vacuum stream by separation systems. In addition to a water ring pump vacuum system, Gneuss also offers deep vacuum systems with corresponding separation devices.

VIS

The Online Viscometer was developed with the goal of achieving measurements which are comparable with laboratory results and to provide a system which provides these accurate values permanently and without influencing the process. Using a high-precision, high-conveying gear pump, a small partial flow of the polymer melt is diverted from the main melt channel and then forced through a precisely manufactured slotted capillary. The viscosity measured there is directly related to the molecular chain length, on which in turn the mechanical properties such as tensile strength and stiffness depend. Quality assurance can be improved by recording and storing this data through the viscometer.

Example of an OMNI recycling system

Technical options:

• direct adaptation to sheet, strapping tape or fibre
  production lines (no need for the intermediate step of
  pelletising)
• blending of additives (in pellet or liquid form)
• highly efficient, process-constant fine filtration
• individually configured feeding systems, including the
  Gneuss 3C Rotary Feeder