Upgrading film recycling process in Chile and Ecuador

2014-11-11
Another 120mm recycling line was installed in Chile in November. In the past 2 years, More than 25 Polystar integrated plastic recycling systems have been put up in Chile and Ecuador alone, mainly to film producers and recyclers. It has helped producers to upgrade their post-industrial and post-consumer film recycling processes to be much more efficient and productive.

Most of the plastic recycling systems used in the two countries in the past (and some today) are commonly known as the "two stage" (mother and baby) extrusion machine with a hopper, a force feeder, two extruders and a strand-die (spaghetti type) pelletizer. The film waste (film scraps and film on-rolls) would first have to go through a crusher or a shredder, then transported into a silo tank and then force-fed into the plastic recycling system.

This normally requires at least 2 operators or more in the whole process, starting from feeding the machine into the crusher to the end of the line.

The crusher normally generates a lot of noise during the process, and the transport of material from the crusher into the extruder is problematic sometimes, because the film flakes are very light in weight and from time to time it creates very inconsistent feeding from the hopper into the extruder, as the low bulk density of the material can make high output difficult to achieve.

Normally, one can reach about 250kg per hour with a two-stage extruder of 100mm in screw diameter.

Polystar's plastic recycling system and its advantages

The machines that Polystar offers are far more efficient comparing to the conventional plastic recycling systems:

The advantages can be easily recognized in the following areas:

  • 1. An Integrated system without the need for pre-crushing:
    The integration of the cutter compactor directly with the extruder eliminates the need for pre-crushing plastic film. The feeding is therefore much faster and more stable. High throughput with the light-weighted film flakes can be easily achieved by going through densification and compacting process first.

  • 2. High productivity
    A 100mm screw (single stage) can achieve more than 400kg in post-industrial LDPE, where as in the conventional line a producer can hardly achieve 300kg.

  • 3. High automation with flexible waste feeding methods:
    The plastic recycling system can process scrap material on a conveyor and film-on-roll on nip roll film feeder simultaneously. This automates the entire process and is beneficial for producers in terms of labor cost saving, space saving and lowering energy consumption. The machine generates very low noise as it does not require a separate crusher to process the film waste in advance.

  • 4. Lower operation cost (less space, lower energy consumption and lower labor cost):
    Polystar's plastic recycling systems can process heavily printed PE/PP film in just one single extrusion stage. This replaces the traditional "two stage" mother-baby extruder pelletizer with less material degradation, as the extrusion process is done in a single stage. At the same time the machine consumes less energy and takes up less space because of its compactness (requires one extruder less and less motor power). In addition, only one person at the feeding section is sufficient for operating the machine.

  • 5. High quality, uniformed sized round shape pellets
    The die face pelletizing system can efficiently produce high quality PP and PE pellets that are ideal for extrusion and injection. The water ring pelletizer does not create waste as it does with the spaghetti type pelletizer.

In the past 2 years, Polystar has installed in total of 25 recycling lines of cutter-compactor type in these two countries alone and about 80 in Latin America. In Chile, Polystar has supplied equipment to big film producers such as Tehmco and Plasticos Bio Bio. In Ecuador, Polystar has also supplied to the biggest T-shirt bag maker in the country Producto Paraiso del Ecuador.

Overview of Polystar's integrated plastic recycling system:

  • • No pre-cutting required: The cutter-compactor design is ideal for light-weight material (film and film flakes)

  • • One stage extruder alone can handle highly printed film -- less material degradation, energy and space saving comparing to traditional plastic recycling systems

  • • Improved filtration and degassing units can handle highly printed material

  • • Self adjusting pelletizing speed for higher quality and more uniform sized pellets

  • • A more compact design with higher output

  • • Improved die-face pelletizing system for PP, BOPP and OPP film/woven/raffia waste



Filtration and degassing

  • • A continuous filter with two flowing channel reduces operator intervention.

  • • The double degassing and high-vacuum can effectively process highly printed and humid material

  • • The re-positioning of the filter and degassing eliminates the problem of material leaking in the vent (degassing) area in conventional plastic recycling systems. This allows producers to achieve higher production and process printed film more efficiently



Application: Post-industrial blown film, cast film, PP woven, nonwoven and raffia waste generated from in-house production. Washed agricultural and post-consumer film waste

Examples: Food packaging, wrapping material, industrial packaging, agricultural film, carrier bags, waste packaging, Shape: Film scraps, film-on-roll, edge trim, raffia, woven, sheet, injection molding waste and many others Condition: non-printed, slightly printed and heavily printed, laminated and multi-layer

Exhibitions:

Polystar will demonstrate its re-engineered plastic recycling system in Mexico (Plastimagen) this month, NPE (Orlando) and Fullplast (Chile) in 2015