WASHING | TECHNOLOGY
Some leading suppliers of washing technologies for
plastics recycling are improving their systems and adapting them for use with a wider
range of plastics. Mark Holmes looks at their developments
New washing products target polyolefins and PET
High-end washing technology is now available for polyethylene (PE) and polypropylene (PP) and more widespread recycling of polyolefins is now a reality. Semi-crystalline thermoplastics, such as PP and PE, are widely used in packaging. These polyolefins account for around 50% of the total plastics packaging market, while PET has only a share of approximately 2.5%. Responding to numerous enquiries from customers and increasing requirements for the recycling of re-usable materials from waste, Krones has developed a washing technology for polyole- fins – the MetaPure W-PO. “For some time, Meta- Pure W has been established and recognised for its washing performance in the recycling process for PET containers,” says Thomas Friedlaender, Head of PET Recycling Plants at Krones. “This is because the sturdy and compact-size washing module has been developed and built for continuous operation
www.plasticsrecyclingworld.com
in plastics recycling lines. Fundamentally, the washing process is the process step that crucially determines the recyclate’s quality: poor washing performance cannot be compensated for during downstream processing of the washed flakes. Meanwhile, there have been greater demands in the market to recycle polypropylene and polyethyl- ene as well, to make them suitable for high-grade re-use. Following extensive trials in our own plant’s washing system, Krones has been able to demon- strate that it is possible to treat these polyolefins and create top-quality recyclates – in a process that is both ecologically and economically viable.” A key characteristic of polyolefins is that their densities are less than one, allowing them to float on the surface of water, while PET is significantly heavier than water, meaning that it sinks to the bottom. “The relative low density of polyolefins and their resulting ability to float are very helpful in the
July/August 2018 | PLASTICS RECYCLING WORLD 43
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54
