18 Oct 2010 Big stride for bottle-to-bottle recycling

PET is always a hot topic and now rPET is starting to make waves in South Africa, with locally-made rPET beverage bottles now available.

AGAINST the backdrop of a world economic crisis in 2009, PET (polyethylene terephthalate) recycling figures in South Africa bucked the trend and continued to escalate. PETCO (PET Recycling Company) reports a recycling rate of 29 048 tons in 2009, 6 311 tons higher than 2008 and equivalent to 32% of the local beverage PET market.

This impressive recycling rate was achieved by PETCO in partnership with its contracted service providers – Extrupet, Hosaf, Kaytech and newcomer, Sen Li Da Chemical Fibre Company,– which combine collection, recycling and end-use into their PET value chains.

“Recyclers are contracted by PETCO as a service to the PET industry to collect and recycle as many used food and beverage containers as possible – not only creating jobs but reducing litter, alleviating pressure on landfill space, and reducing dependence on finite crude oil reserves. ‘However, our collection rate would not be possible without financial support from bottlers, converters, raw material suppliers and Coca-Cola South Africa,”’ comments PETCO CEO Cheri Scholtz.

Last year turned out to be a landmark year in more ways than one. Firstly, 2009 saw the expansion of the Extrupet plant in Wadeville to produce food grade recycled PET (rPET) for the food and beverage industries. This landmark development means that a percentage of rPET can be put back into virgin containers, thereby closing the packaging loop and providing a new end-use market for rPET,– a first in South Africa.

As Cheri Scholtz remarks: ‘”If we are to grow the tonnage of PET collected and recycled, this development is the key.’”

Secondly, PETCO welcomed the start up of the Sen Li Da, a recycler based in Newcastle, KZN, and entered into a contract with this company in early 2010. Sen Li Da has established a vertically-integrated plant that recycles post-consumer PET bottles into 3D conjugate hollow fibre that’’s sold into the South African market and is likely to displace some imports. Products made from this fibre include carpeting, pillows, blankets, roof insulation and automotive seats.

Another important factor last year was the enactment of the Waste Management Act, which defines the waste hierarchy and brings the concept of extended producer responsibility to South Africa.

Hilfort takes the gap

Just two years ago, Astrapak’’s Hilfort Plastics operation in Cape Town made news with the introduction of South Africa’s first transparent multilayer polypropylene (PP) containers. Now the company is taking the lead again, this time pioneering the use of post-consumer rPET for the production of food and beverage bottles.

‘”We’’ve been through some challenging times,’” admits Hilfort Plastics MD, Robin Olbrich, by way of background to this latest project. ‘”The recession hit harder than we expected, but Astrapak’’s strategy is to spot new business opportunities and to drive excitement back into the market to stimulate industry growth.’

“One such business opportunity is rPET. ‘We feel very strongly about the opportunities for rPET,’” Robin says. ‘”This is a very important part of our sustainability report, as retailers particularly are pushing hard for a reduction of carbon footprint. In addition, there’’s constant pressure on our industry to keep government intervention at bay by being proactive on the recycling front,’” he adds.

This Astrapak project is undoubtedly a first – and very important – step towards closing the loop and achieving true bottle-to-bottle recycling, which, as Robin accurately identifies, is something of a ‘holy grail’ in the packaging industry.

As a result, Hilfort is moving into the processing of rPET into soft drink bottles, initially targeting the non-carbonated sector.

“‘An important step in this project has been to demonstrate that, in terms of lifecycle analysis, bottle-to-bottle PET recycling is environmentally and economically sound”,’ Robin explains.

One goal is to eliminate dependency on virgin PET resin. And there are other benefits. For example, the bottle-to-bottle recycling process uses less energy than it takes to produce virgin PET from fossil fuels.

Hilfort is using rPET from Extrupet, where, thanks to its recent investment in Erema technology the company is making available some 5 000 tons/annum. However, explains Extrupet’s Chandru Wadhwani, this will grow to 7 000 tons next year as his company will be investing in further capacity.

rPET safe for food contact

In 2000, the US Food & Drug Administration (FDA) officially approved the Erema post-consumer PET recycling system for the production of recycled pellets from returned soft drink and mineral water bottles for reuse in direct contact with food. The tests for this approval process were carried out by the Fraunhofer Institute for Process Engineering & Packaging in Germany.

Highly specialised equipment is required to purify and flake the used PET that’s collected. Equally specialised is the gear that converts the flake back into a food-grade product that can take the place of virgin PET.

Using Erema’’s recycling technology, in addition to having FDA-approved quality, the recycled pellets also have a viscosity slightly lower than that contained in virgin material, but with next year’s planned upgrade at Extrupet, the viscosity will come closer to that of virgin polymer.

For reprocessing PET for conventional applications such as fibres or thermoforming sheet, the application of a vacuum on the cutter compactor is sufficient. However, the manufacture of beverage bottles requires an intrinsic viscosity (IV) above 0,80. For this purpose, a pellet viscosity increase of the post-consumer material is required.

Erema solves this problem by using a specially-developed continuous crystallisation dryer positioned prior to the main recycling process. In a single step, material is pre-heated, dried and pre-crystallised in the crystallisation dryer. Following this, free-flowing flakes enter the vacuum cutter-compactor via a thermal-insulated feed system and a vacuum sluice. At high vacuum, not only is residual moisture minimised owing to loaded rotational energy and appropriate dwell time at high temperatures, but the material is effectively purged of impurities and at the same time receives the desired increase in viscosity.

Online IV monitoring equipment ensures material with constant IV, while impurity level control ensures constant FDA food-grade quality.

Extrupet T +27 011 8658360; Hilfort Plastics T+27 021 9415060; PETCO +27 021 7889954

First published in PACKAGiNG & Print Media, September 2010.