Executive Summary on "Large scale demonstration of the viability of Recycled PET (rPET) in Retail Packaging" in Czech

Project code: PLA0032

Written by:
Martin Rodgers
rPET Project Manager
Coca-Cola Enterprises Ltd

Published by:
The Waste & Resources Action Programme
The Old Academy, 21 Horse Fair, Banbury, Oxon OX16 0AH
Tel: 00-44 01295 819900
Fax: 00-44 01295 819911
www.wrap.org.uk
WRAP Business Helpline: Free phone: 00-44 0808 100 204

2 Executive Summary
(pages 4 - 7 of 29 only!)

This project has successfully demonstrated that 3 different food grade recycled PET resins, URRC, Supercycle and Ecoclear, when within (resin) specification and processed correctly can produce acceptable 500ml, 26g carbonated soft drink bottles.

1. URRC resin was approved at both 25% & 40% blending rates with virgin PET
2. Supercycle resin was approved at 25%, 40% & 50% blending rates with virgin PET
3. Ecoclear resin was approved at a 25% recycled content /*

/* Ecoclear comes pre-blended at a variety of recycled rates with its virgin component

All the resins were approved after a series of small scale trials at CCE’s Wakefield site, where a number of bottles were produced and sent to TCCC’s (e.g. The Coca-Cola Company - TCCC) approval laboratory in Brussels for testing. The results of the testing proved to be acceptable for all the resins described above, despite all the samples showing lower CO₂ retention times than that seen with virgin resins.

Based on these results and the supply chain impact of running large quantities of pre-blended rPET it was decided to only assess longer term viability on Supercycle and URRC blended with virgin resins at a 25% inclusion rate.

Although Ecoclear has the advantages of coming pre-blended and hence no capital blending equipment is required, it was not compatible with the operational constraints of this particular trial.

A 25% blend of Supercycle began running in September 2005, initially just at East Kilbride, then from November 2005 it was also run at Sidcup. The material has performed excellently with some 75 million bottles, with 2 different virgin resins, being produced and shipped by the end of April 2006. These bottles consumed ~500T of Supercycle meaning the original ‘volume’ objective of this part of the project was fully met.

• Runs with a wider ‘processing window’ than virgin resin
• Where accurate measurement of energy usage was possible, Supercycle consumes marginally less energy (~1%), during bottle manufacture, when compared to running purely 100% of the virgin resin, however further investigation is required
• No significant difference in quality or consumer comments for rPET bottles vs virgin resin bottles is seen, based on six months monitoring of consumer feedback

• Only 17,000T of Supercycle material are available annually from a single European Amcor plant, its pricing can vary above and below virgin pricing due to cyclical trends of PET at a global level

• The performance of Supercycle resin has a similar performance level when compared to current virgin materials.

This trial had limited success, some larger sized specks were seen, however the main cause of problems was with ‘holes in the bottles feet’ leading to the possibility of bursting bottles, which were seen approximately every 15,000 bottles through out the trial. Based on limited evidence from the trial, larger specks of contamination, which escaped detection, may have been responsible for the failures.

A detailed investigation was conducted at the preform supplier, Constar, to identify the possible causes of the black specks and how best to proceed. The findings were as follows:

1. There is a low level of very small black specks (sized <<0.5mm) in the flaked URRC rPET resin as supplied by Cleanaway - at this level it is well within the TCCC’s tolerance for contamination.

2. The larger sized, more serious black specks are believed to be caused by degraded/burnt PET which builds up in the screw, barrel and manifold of the injection machine before being blown out in to the preforms, during the manufacturing process.

This degrading problem was addressed in 2 ways:

• The barrel and screw of the moulding machine were removed examined and cleaned. In side the barrel, prior to cleaning, a small amount of burnt PET identical to the specks seen in preforms, both visually and in terms of their chemical composition was observed
• The injection moulding operating temperatures were reduced from 300 ^oC to 280 ^oC to potentially reduce any further degradation and build up of PET in the barrel

This work appears to have been successful, with subsequent preform production having shown a reduction in black speck contamination to well within TCCC specification. This new production needs to be trialed to assess if the improvement in black specks corresponds to an improvement in bottle blowing performance allowing an extended bottle blowing trial to be completed. If a large scale T2 trial is completed successfully then CCE may be able to continue with a much large ~75M trial of URRC.

Black speck contamination (outside of TCCC specification) in preforms remains a serious barrier to the wider use of this material. The specks appears to be made up of:

1. An inherent, generally low number of small sized, and within TCCC specification, black specks in the recycled resin
2. Larger number and larger size (>1-2mm) of degraded/burnt PET specks, well outside of TCCC specification which appear to be formed during preform manufacture by the convertor, leading to cosmetic failures and possibly contributing to burst bottles

Excellent energy measurement equipment exists on the line trialing URRC, based on the limited experimentation URRC consumes up to 3% more energy during bottle manufacture than when running purely 100% virgin resin – however this increase must be put into the context of only running a relatively small number of bottles and may well not represent ‘steady state’. However further investigation is required.

Apart from black specks no other significant differences in quality or consumer feedback are seen when comparing 25% URRC bottles vs virgin resin bottles

Material is readily available and competitively priced

• The project has helped demonstrate that rPET is a viable alternative to 100% virgin PET in the demanding application of CSDs for CCE
• Supercycle could be used at 25% in CCE’s 500ml CSD bottles subject to the commercial factors of supply and price.
• Although URRC is viable in terms of its availability and pricing much further work with the preform convertor and a large scale trial is required to prove its ‘long term quality’ viability.

Related links on IP PETrecycling.cz in English only:

• Czech Gateway to the PET bottles Recycling

More articles on IP PETrecycling.cz:
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