Plastic Extrusion Technologies For Waste to Energy and Recycling

PLASTIC EXTRUSION EQUIPMENT

The ONESTEP Extrusion System by MAS is making its North American debut at this year’s NPE Tradeshow in Orlando. Unlike other extrusion systems, the ONESTEP is the only system that combines two major processes – recycling and compounding – into one. Simplicity at its best. Furthermore, this new extrusion system brings together the familiar superior plastification and homogenization of a parallel twin screw extruder with the specific advantages of the conical twin screw system. Learn More…

The MAS Extruder 45, 55, 75 & 90

Maximum Added Value in Production

The MAS Extruder is based on a conical, co-rotating twin screw extruder. The excellent process engineering characteristics of MAS extruders are achieved first and foremost by the high disposable volume and high coverage of the co-rotating screw shaft. Due to the conical design the intake volume is significantly greater than the discharge volume, resulting in an extremely high screw filling level. This leads to high volume throughput per revolution with excellent melt pressure stability and at the lowest possible melt temperature.

The technology benefits:
  • Large input volumes and thus excellent feeding characteristic
  • High melt pressure build-up and maximum pressure stability, thus removing the need for a melt pump in most cases
  • Large shaft diameters allow for high torque
  • Easy removal of the screw via the rear of the extruder
  • Excellent homogenization characteristics
  • Excellent feeding behavior guarantees a short melt retention time in the extruder at low melt temperature
  • Extremely low specific energy consumption

Individually configurable

The screw assembly of the MAS compounder consists of a feeder and an extractor screw. Each of them is manufactured from one piece and available in a number of different pitches and number of starts. The mixing and shearing parts are customized to reflect the buyer’s individual requirements. The cylinder zones are equipped with heating shells and liquid cooling. The three-part cylinder can also be modified to match customer requirements. (with/without de-gasification, position of de-gasifying aperture etc.).

The mixing and plasticizing capacity is set by replacing the screw elements. Due to the conical design, an extremely fast screw changeover is possible. The downstream equipment remains in situ, the cylinder is swiveled out and the screws can be pulled out to the rear without further tools.

Compact, robust, durable

Generous axis spacing ensures a large intake volume and thus guarantees perfect feeding performance. Shaft diameters are dimensioned accordingly, allowing the use of robust thrust bearings and thus transmission of high torque.

Type Material Output
MAS 45 e.g. PE / PP / PS / PET approx. 300 kg/h
MAS 55 e.g. PE / PP / PS / PET approx. 600 kg/h
MAS 55L e.g. PE / PP / PS / PET approx. 600 kg/h
MAS 75 e.g. PE / PP / PS / PET approx. 1000 kg/h
MAS 90 e.g. PE / PP / PS / PET approx. 1500 kg/h
MAS 93 e.g. PE / PP / PS / PET approx. 1800 kg/h
Best quality in PET extrusion

The MAS extruder is perfect for processing A PET, G PET and GAG PET, both for re-pelletizing and for direct extrusion to products. The large aperture in the conical extruder supports feeding of both PET grinding stock (e.g. from PET bottles and preform) and of ground cast or BOPET foils. There is no need to pre-crystallize or pre-dry the PET.

As the extruder’s intake volume is significantly greater than the discharge volume, an extremely high screw filling level is achieved. This helps to achieve high output values at slow screw speeds and at a correspondingly low melt temperature. This results in excellent color values and lowest possible IV loss. The low thermal load, accompanied by very low specific energy consumption (≤ 0.22 kWh/kg) thus allows for highest quality extremely economically.

Direct extrusion of WPC / PPC / NFC

Due to the conical design and the resulting excellent pressure stability of the extruder, process reliability in direct extrusion of WPC/PPC and NFC profiles is ensured. Extruded WPC/PPC/NFC profiles with a wood, paper or fiber content of up to 80% and at the same time excellent mechanical characteristics are unique selling points in this market sector for MAS extruders.

Customer-specific solutions

MAS co-operates closely with IFA Tulln, the Institute for Natural Materials Technology at the University of Natural Resources and Applied Life Sciences, Vienna. Together, we develop holistic concepts including suitably stable process technology – from the initial idea to the development of product-specific recipes with profile extrusion trial runs and analysis of mechanical characteristics to prove the process and product are all undertaken.

Compounding

The conical, co-rotating MAS extruder offers process stability and economic compounding of plastics with very different characteristics wherever it is necessary to fulfill the strictest quality requirements. Especially in the following areas:

  • WPC (Wood Plastic Composites)
  • PPC (Paper Plastic Composites)
  • Dies
  • additives
  • talcum
  • CaCo3
  • wood powder
  • natural fibres
  • paper
  • cellulose fibres
  • carbon black
  • glass balls
  • glass fibres
  • wax
  • graphit
  • colours

Thanks to its conical design with a substantially larger feed volume, the MAS extruder offers decisive advantages. From a process technology point of view, excellent results are achieved even when admixing/compounding high volumes of glass fibers (more than 50%) with a PE/PET or PP melt. A single admixing aperture is used to feed all materials. Complicated multiple dosing, which is typical for cylindrical designs, is totally unnecessary.

Continuous Melt Filtration

Wood and paper are very common impurities in plastic recycling. Conventional filter systems using mesh screens are usually unable to cope with even small amounts of such impurities. The continuous CDF-type melt filter separates contamination such as paper, wood, aluminum or rubber efficiently. A scraper removes the contamination from the surface of a rotating screen disc. The impurities are discharged continuously from the CDF, while the filtrated melt is forwarded to the pelletizing system. The melt pressure in front of the filtration disc controls automatically the function of the Scraper.

Easy Maintenance – Filter Disc Replacement

The filter discs are manufactured from hardened steel with hole sizes from 180 μm up to 800 μm. Replacement is very simple as the filter screen is freely accessible once the split housing has been opened. Consequently, the filter screen can be replaced within approximately 40 min using conventional tools.

Extrusion / Recycling

Recycle Films and Add Value by Compounding
The large infeed opening makes the MAS extruder a perfect recycling machine. Materials with a low bulk density, such as film flakes, can easily be fed in. They do not have to be compressed beforehand using special devices. Additives such as hydrated magnesium silicate (talc) or calcium carbonate, stabilizers, or dyes can be metered into the film flakes and fed into the system at the same time. Side feeders do not have to be used. The comparatively large contact surface of the screws with the material allows a large amount of energy to be conveyed to the plastic. This enables the plastic to be melted quickly over a short path and also enables a compact design, especially in comparison to single screw recycling systems. Kneading elements integrated into the screws support homogenization. The large overlap of the screw profiles increases the delivery rate and stabilizes the melt pressure. A melt pump for building up and stabilizing pressure is therefore no longer required. The conical screws of the modular system can be fitted for the specific task, which allows them to quickly and easily be adapted to various uses as needed.

Example of a cascade extruder that can directly compound recycled materials. The conical, co-rotating extruder by MAS is combined, in this case, with the new MAS melt filter system and a single screw extruder with degassing.

Low Energy Consumption from Start to Finish
The compact MAS extruder is the key element of an integrated recycling and compounding system in the form of a cascade extrusion System. The MAS extruder is combined with an MAS melt filter system (for continuous filtration with a planar array filter) and a downstream single screw degassing extruder. The overall efficiency of the system is highly impressive. In compounding mode with a supply of 60% PP film flakes and 40% powdered additives, a specific energy consumption of only 0.24 kWh/kg is easily achievable!

The conical co-rotating design of the MAS extruder supports a versatile range of applications. The MAS extruder is suitable for virtually any application in the extrusion sector:

  • Recycling of polyolefins and technical plastics
  • Recycling of plastics that are sensitive to temperatures and shearing
  • Admixing of dies, additives such as CaCO3, talcum, etc.

The MAS extruder is perfectly suited for any application where high quality requirements and a variety of product requirements necessitate an individual solution.

Brochures (PDF) :
PET Extrusion, Compounding, WPC, Compact Plastics Recovery,CDF Overview,MAS Extruder Overview
MAS Extruder – Conical co-rotating
MAS 24 – Laboratory Extruder
MAS-Cascade – Recycling and Compounding
MAS Extruder – The right answer for every PET application
MAS CDF – Filtration of the highest caliber