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arge scale demonstration of the iability of Recycled PET (rPET) n Retail Packaging

oca-Cola Enterprises Ltd

roject code: PLA0032

ate of commencement of research: 1st December 2004 inish date: 31st March 2006

inal Report March 2006

ritten by: artin Rodgers

PET Project Manager oca-Cola Enterprises Ltd

ublished by: he Waste & Resources Action Programme he Old Academy, 21 Horse Fair, Banbury, Oxon OX16 0AH el: 01295 819900 Fax: 01295 819911 www.wrap.org.ukRAP Business Helpline: Freephone: 0808 100 204

une 15th 2006 SBN1-84405-273-7

http://www.wrap.org.uk/

Contents

1 Glossary ..............................................................................................................3 2 Executive Summary ..............................................................................................4 3 Scope of Project ...................................................................................................8 4 Introduction.........................................................................................................8

4.1 Coca-Cola and rPET background .....................................................................8 4.2 Background to Coca-Cola Enterprises (GB) Ltd and it’s Segments.......................9 4.3 CSD Bottle manufacture .................................................................................9

4.3.1 PET resin................................................................................................9 4.3.2 Preform Manufacture............................................................................. 10 4.3.3 Common preform faults ......................................................................... 12 4.3.4 Bottle blowing....................................................................................... 13

5 rPET.................................................................................................................. 14

5.1 Recycled Resins available ............................................................................. 14 6 CCE’s rPET Trials ................................................................................................ 16

6.1 Summary of T1 trials.................................................................................... 16 6.1.1 Detailed T1 trial findings ........................................................................ 17

6.2 Supercycle T2 & T3 trials.............................................................................. 21 6.2.1 Consumer Feedback analysis of Supercycle Production ............................. 21 6.2.2 Processability of Supercycle.................................................................... 22

6.3 Conclusions from Supercycle trials................................................................. 22 6.4 URRC T2 trial .............................................................................................. 23 6.5 Details of investigational work conducted at Constar on URRC failures ............. 24 6.6 Conclusions from URRC trials ........................................................................ 25

7 Conclusions & Next Steps.................................................................................... 26 8 Appendix ........................................................................................................... 28

Viability of rPET in retail packaging – Martin Rodgers of 29

1 Glossary

AA Acetaldehyde a breakdown product of PET which can cause off taste in products Alpla A preform convertor BBE Best Before End – consume product by date CCE Coca-Cola Enterprises – A Franchisee of TCCC who are the bottler of Coca-Cola

products in the UK Closure The cap or bottle top CO2 Carbon dioxide the gas added to soft drinks to provide carbonation - fizz CSD Carbonated soft drink e.g. Coca- Cola, Sprite & Fanta Ecoclear Resin producer Wellmans’ recycled PET material IV Intrinsic viscosity a measure the degree of polymerisation of a polymer, the longer

the chains the stiffer the material and the higher the IV PET Polyethylene Terephthalate – the plastic polymer used in the manufacture of bottles Preform An interim stage injection moulded container which is a precursor to a finished

plastic bottle Resin Term used to describe PET when available as a raw material rPET Recycled Polyethylene Terephthalate – a general term used to cover any of the

different types of recycled PET material Supercycle (SC) Packaging company Amcor’s recycled PET material T1 CCE term for a small scale production trial involving several thousand bottles. T2 CCE term for a large scale production trial assessing longer term manufacturing

viability, involving 100,000s of bottles. TCCC The Coca-Cola Company URRC United Resources Recovery Corp – a form of recycled PET available in flake or

through further processing the usual pellet form Virgin resin A PET resin made from new production with no recycled content WRAP Waste & Resources Action Programme - the sponsors of the project


2 Executive Summary

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.

• URRC resin was approved at both 25% & 40% blending rates with virgin PET • Supercycle resin was approved at 25%, 40% & 50% blending rates with virgin PET • 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 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. Longer Term Supercycle Viability – Recycled resin and preforms sourced from Amcor 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. Key findings for Supercycle

• 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. Longer term URRC Viability – Recycled resin sourced from Cleanaway, preforms sourced from Constar A large scale, 25% blend rate, URRC trial was started in December 2005, but was abandoned after only 100,000 bottles had been produced due to a high level of black speck/flake contamination seen in the bottles. It was determined that the specks posed no food safety or health issues but are cosmetically unsightly, and outside TCCC specification for cosmetic failures.

Based on these results all the remaining preforms from this batch of production were sent to Alpla (a preform converter in Belgium) as they have a camera system capable of inspecting/rejecting contaminated preforms. The preforms were run through Alpla’s camera system and sorted into acceptable preforms (i.e. those specks under 1mm in size) whilst rejecting preforms with larger sizes of contamination. These acceptable preforms were then used in a second large scale bottle blowing trial

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 300oC to

280oC 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. Key findings for 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:

o An inherent, generally low number of small sized, and within TCCC

specification, black specks in the recycled resin o 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


Summary

• 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.


3 Scope of Project

This project aims to demonstrate that recycled Polyethylene Terephthalate (rPET) can be successfully adopted and incorporated in retail packaging: it entails the production and retail distribution of soft drink products utilising packaging containing rPET and will cover internal viability (sourcing, production and processing) and external acceptance (consumer appeal). This project focuses on a key segment; the 500ml PET carbonated soft drink (CSD), as much of the post consumer waste generated from this pack size is available for recapture through household collection systems. The project:

• Carried out production and segment trials to demonstrate the large scale feasibility of using 25% recycled Polyethylene Terephthalate (rPET) in retail packaging applications for soft drinks and demonstrating through the consumption of ~500 Tonnes of rPET that it can be successfully adopted and incorporated.

• Established producer acceptability of using recycled material and overcame several

real and perceived barriers.

• Generated information that is being disseminated and made publicly available by WRAP to facilitate and encourage the increased use of rPET in further retail packaging applications.

4 Introduction

4.1 Coca-Cola and rPET background The introduction of PET to the soft drinks bottling category in the 1970’s revolutionised container technology for all beverage suppliers. The Coca-Cola Company (TCCC) has been at the forefront of extending this revolution into the use of post consumer rPET. TCCC’s products in USA, Netherlands, Belgium, Switzerland, Germany, Sweden, Australia, Japan and Mexico all have some degree of rPET content. However rPET is absent in Coca-Cola products in GB, Spain, Italy and France. European Union and national recycling targets affect the future of CCE’s business in general and due to recent legislation PET in particular. In 2001, all EU member states were required to meet a 15% plastic packaging recycling target (P&PW Directive). This will increase to 22.5% for 2008. These targets have stimulated the need to continue with current environmental initiatives e.g. Recoup Valpak and recycling zone as well as investigating fully & understanding the issues surrounding the implementation and longer


term uptake of rPET in bottling. This work is inline with the Corporate Social Responsibility (CSR), which is a fundamental principal with the Coca-Cola System. 4.2 Background to Coca-Cola Enterprises (GB) Ltd and it segments The Coca-Cola Company (TCCC) owns the Coca-Cola brand in addition to over 400 others. TCCC is responsible for marketing 20 brands (over 100 products) in Great Britain. Coca-Cola Enterprises Ltd (CCE) is a subsidiary of Coca-Cola Enterprises Inc, which in turn is part owned by TCCC. CCE is the Worlds largest producer and distributor of TCCC products. In GB CCE manufactures both ‘Coca-Cola’ and ‘Schweppes’ products, having 6 manufacturing sites, 11 Distribution centres and 16 full service vending depots in 8 regions, employing some 5000 people. CCE’s products include ‘Coca-Cola’, ‘Fanta’, ‘Sprite’, ‘Dr Pepper’ and ‘Schweppes’. CCE manufactures a diverse range of size and pack types including glass, PET and cans. All the work on this project was conducted on 500ml bottles. CCE supplies approximately 900 million such bottles per annum. Estimate of CCE’s 500ml sector recovery programmes Sales channel

% of CCE’s sales

Main Consumption

point

Of these sales waste arising at:

Recovery programme

Wholesale 36% Home Home = 25% Household

Grocery 23% Home Home = 23% Household

Retail 20% Out of Home Home = 5% Leisure = 5%

Household Municipal

Cold 20% Out of Home Leisure = 5% Home = 5%

Municipal Household

Licence 1% On premise On premise=100% None

4.3 CSD Bottle manufacture CCE use a two stage bottle manufacturing process, Beverage bottles are produced from PET resin which is injection moulded by a third party supplier to produce an interim stage container, called a ‘preform’. These preforms are then blow moulded either in-house by CCE or by a third party supplier to form a finished plastic bottle. All 500ml CSD bottles are produced from a standard 26g preform. This standard perform can produce a number of different bottle styles; e.g. ‘Fanta’, ‘Coca-Cola’ and ‘Dr Pepper’. 4.3.1 PET resin PET first came to notice in the 1950’s as a textile material. However in the 1970’s it began to be seen as an ideal lightweight replacement for carbonated soft drink glass


bottles. PET is produced from a reaction between two chemicals, purified terephthalic acid (PTA) and ethylene glycol (EG).

It is a long chain molecule made up of the above repeating polyester chain. Main advantages of PET resin in beverage bottling. Crystal Clear Products look appealing in clear bottles

Pure PET complies with international food contact regulations

Safe PET bottles are hard-wearing - difficult to break and don’t shatter.

Lightweight 10% weight of an equivalent glass pack

No Leakage/adequate CO2 retention PET prevents beverage leakage and retains CO2 levels

Design Flexibility Suitable for containers of all shapes and sizes

Recyclable Used (post consumer) PET bottles can re-processed back into new PET bottles or employed as material for strapping, carpeting & fibre filling.

4.3.2 Preform Manufacture Although two different preform converters (Amcor in Gresford and Constar in Sherburn) are used by CCE; in manufacture the basic process is the same, having four main stages, drying, melting, injection forming and cooling. Drying:

The PET pellets have to be dried, reducing the moisture to lower than 40 parts per million. The dryer is heated and the pellets are left at an elevated temperature for several hours. Any residual moisture left in the resin can adversely affect both processability of the resin in the forming stages and finished bottle performance by lowering the intrinsic viscosity (IV) of the resin which can lead to stress cracking in the filled bottle

Melting/Injecting Forming:

The dried PET resin pellets are then transferred to the injection moulding machine. These machines have a heated, screw fed barrel and a (pre)forming tool. The material is melted as it travels along the screw prior to injection into a multi cavity (mould) tool which forms/moulds molten resin in the preform shape.


Husky Injection moulding machine

Cooling

The preforms are then cooled in the tool to prevent crystallisation before being ejected for use

Viability of rPET in retail packaging – Martin Rodgers

Finished preforms

of 29

4.3.3 Common preform faults A number of faults can be seen during preform production, these are split into four broad categories: 1. Physical dimensions (outside of specification) Preform weight, Wall thickness, Incomplete neck, Flash and Perpendicularity 2. Appearance

Ovality Neck thread not formed correctly Black specks Air bubbles Un-melted resin particles

Foreign inclusions Crystallisation

Off Colour

Injection point too long/short

3. Acetaldehyde level (AA) Caused by PET degradation during the melting phase which gives a fruity flavour in the beverage 4. Loss of Intrinsic Viscosity (IV) Caused during the drying & Melting operations and resulting in stress cracking and bottle failures


4.3.4 Bottle blowing The preforms are conveyed into a bottle blower where they are heated to soften the material prior to blowing by infrared lamps. The lamps are set in patterns and their output is adjusted to control the bottle profile. The heated preform is then stretch blown into a bottle shaped mould to produce a finished container. This whole operation occurs at high speeds - on modern bottle blowers over 50,000 bottles an hour can be produced.

Incoming preforms are inverted Heated by an oven/infrared lamps Stretched and blown in to shape Further Bottling processes Once blown, the bottles are washed, labelled and then filled with beverage before being capped and packaged for despatch.


5 rPET

5.1 Recycled Resins available There are numerous food grade rPET resins available on the market, however due to the high standards and rigorous requirements of TCCC the selection for this project is restricted to 3 resins. Of these two were thoroughly investigated: Cleanaway’s – URRC material Amcor’s – Supercycle material In addition Wellmans Ecoclear material was given a preliminary assessment, but not examined further due to its being pre-blended with its own virgin component and the impact this would have on CCE’s supply chain volumes. . The URRC process is unique in producing the rPET in both a flaked and pellet form. As the flaked form process does not include an extrusion or solid stating phase the flaked version of URRC has a significant cost advantage over its pelleted rivals. However, the lack of a final melt filtration stage leaves the flakes susceptible to small levels of ‘black speck’ contamination.

Flaked post consumer material Clean URRC flaked rPET In contrast both Supercycle and Ecoclear are in pellet form (i.e. undergo melt filtration) with Ecoclear coming pre-blended with its virgin resin.


Advantages and disadvantages of all 3 rPETs

rPET Option Advantages Disadvantages URRC • The material is cleaned and

processed without the need to undergo a final melt phase, reducing costs, whilst still approved for direct food contact

• Up to 50% of rPET can be mixed with virgin PET

• Technology licenses are available for manufacturers to set up new facilities using this technology, and it is widely available

• In general due to the reduced processing to produce flaked material it is the cheapest form of rPET available

• Same organoleptic properties as virgin PET.

• Approved for direct food contact applications.

• As the material doesn’t go through a final melt and filter phase it is possible for some small levels of ‘black speck’ contamination to remain

• Flakes need to be blended with virgin resin by the converter prior to injection moulding, requiring accurate mixing/blending equipment

• Has a lower IV than other rPET materials available

Supercycle • Same physical, mechanical, and organoleptic properties as virgin PET.


• Material is solid stated to increase IV

• Restricted to purchase of preforms from Amcor.

• Only 17K Tonnes available annually from one European plant

• Recycled content restricted by appearance defects with significant deterioration seen at levels over 40/50%

• Supercycle material need to be blended with virgin resin by the converter

Ecoclear • Same physical, mechanical, and organoleptic properties as virgin PET.


• Available to any preform converter.

• Comes pre-blended with the virgin material, removing the need for blending equipment

• Restricted to purchase resin from Wellman.

• Recycled content restricted as there is deterioration in cosmetic appearance in rPET levels over 40%

• The advantage of pre-blending may not off-set higher purchase cost.


6 CCE’s rPET Trials

The objective of the trials is to demonstrate the viability of running rPET at a minimum rate of 25%, i.e. 25% rPET blended with 75% virgin PET. All the trials were run on 500ml, 26g ‘Coca-Cola’ bottles. The key success factors in demonstrating this viability are that the safety, quality, customer perception and costs of processing rPET are equivalent or better to that seen when running virgin PET. The aim was to consume 500 Tonnes of URRC material and 500 Tonnes of Supercycle material during the course of the project, this equates to approximately 150 million 26g 500ml bottles being produced, filled and despatched. CCE has a rigorous trial protocol regime (Appendix A) and in conjunction with this TCCC have a strict approval and testing process which needs to be successfully completed before any bottles can be filled with product or sent to market. CCE have a 3 stage trialling process:

• T1 – a small scale trial to prove that acceptable bottle can be blown and to provide samples to be sent to TCCC for laboratory approval testing.

• T2 – (on approval from T1) a larger scale trial is undertaken which is a longer run

where many hundred of thousands of bottles are produced, filled and shipped. Filling and despatch of the product allows CCE to monitor any customer or consumer feedback it also allows for an understanding of any process variations during a run.

• T3 - is essentially the switch over to large scale production quantities.

6.1 Summary of T1 trials All of the trials were at CCE Wakefield on line 8, with a Sidel bottle blower. Of the three types of rPET tested in these initial T1 trials all 3 passed TCCC’s testing and approval process.

• URRC resin was approved at both 25% & 40% blending rates with virgin material • Supercycle resin was approved at 25%, 40% & 50% blending rates • Ecoclear resin was approved at 25%.

The full range of testing was completed, no visual/cosmetic/colour or dimensional failures were found however two areas showed intriguing findings;


• Stress cracking Several initial tests with URRC badly failed the stress crack test, investigation indicated this was because the material had not been adequately dried, the trials were repeated and acceptable results were achieved.

• CO2 retention

All rPET bottles showed a significant reduction of up to 11% in CO2 retention results when compared to the average for virgin material, but were still deemed to be acceptable. This reduction is most likely due to the lower IV of rPET, despite Supercycle & Ecoclear undergoing final solid stating phases to enhance IV to those levels seen in virgin material

6.1.1 Detailed T1 trial findings In the project numerous T1 trials were run. Virgin PET material

and & content Virgin PET Supplier

RPET material and % content

rPET resin Supplier

Preform Converter

75% S93 Equipolymers 25% Supercycle Amcor Amcor 75% S98 Equipolymers 25% Supercycle Amcor Amcor 75% CB11E Eastman 25% Supercycle Amcor Amcor 60% CB11E Eastman 40% Supercycle Amcor Amcor 50% CB11E Eastman 50% Supercycle Amcor Amcor 75% Permaclear Wellman 25% Ecoclear Wellman Constar 75% CB11E Eastman 25% URRC Cleanaway Constar *75% CB11E Eastman 25% URRC Cleanaway Constar 60% CB11E Eastman 40% URRC Cleanaway Constar *60% CB11E Eastman 40% URRC Cleanaway Constar 50% CB11E Eastman 50% URRC Cleanaway Constar 75% Laser+ Advansa 25% URRC Cleanaway Constar 60% Laser+ Advansa 40% URRC Cleanaway Constar

*2 trials were repeated due to anomalous stress cracking test results All of the above combinations of virgin and recycled resin were measured against the trial’s success criteria. The bottles were subject to the full range of TCCC testing criteria, however as the resins are all approved in terms of food safety and all cosmetic/dimensional checks were acceptable; the findings for the purposes of this report are limited to: resistance to stress cracking & CO2 retention. Stress Cracking This is an extreme test where the bottles are placed in a heated caustic solution and the time taken for the bottle to fail is recorded. It is designed to assess the bottle’s resistance to any stress cracking initiators it may encounter in the field. This is a vital test for rPET as recycled material has a lower IV than virgin and there is a direct link to lower IV levels in resin and bottle failing due to cracking.


Stress Cracking Results

rPET/Virgin PET blend

Survival times Findings

Minimum survival time (mins) (specification = no failures <5mins)

Maximum survival time (mins) (specification = no upper limit)

25% SC/75% S93 18 55 PASS 25% SC/75% S98 18 50 PASS 25% SC/75% CB11E 15 38 PASS 40% SC/60% CB11E 14 32 PASS 50% SC/50% CB11E 8 42 PASS 25% EC/75% PC 9 55 PASS 25% URRC/75% CB11E 1 13 FAIL 40% URRC/60% CB11E 1 7 FAIL 50% URRC/50% CB11E 1 6 FAIL 25% URRC/75% Laser+ 8 21 PASS 40% URRC/60% Laser+ 7 17 PASS The findings indicated a very serious failure rate for the trials completed with URRC material and CB11E. These findings necessitated lengthy investigation into the root causes. The cause was determined to be a processing issue during the manufacture of the preform at Constar. The preforms were produced on a test rig as the volumes of material being handled were much smaller than for normal production runs; the resin was dried quickly in an infra-red dryer rather than a large heated drying vessel where the resin resides for several hours. Although no material was left to perform analytical testing it seems likely that the resin was not fully dried leading to the retention of moisture which lowered the IV and resulted in bottle failures during the stress crack testing. The injection moulder was physically smaller than a normal machine and during the in feed process due to nature of flaked material the neck of the machine would become blocked with the flaked material as it is much more uneven in shape than pellet. Trials with higher percentage contents were very difficult to process as this blocking problem increased with increasing URRC levels. The way forward was to repeat all the UURC/CB11E trials on production drying and injection machinery. This switch over proved to be successful eliminating the stress cracking problems.


Retest of Stress Cracking - Results

rPET/Virgin PET blend

Survival times Findings

Minimum survival time (mins) (specification = no failures <5mins)

Maximum survival time (mins) (specification = no upper limit)

25% URRC/75% CB11E 12 26 PASS 40% URRC/60% CB11E 11 19 PASS 50% URRC/50% CB11E Not rerun Not rerun CO2 Retention results CO2 retention is an important test to ensure that products reach the consumer with sufficient retained CO2 levels; in simple terms this test checks how long the product keeps its fizz. It is a vital factor in determining product shelf life. The bottles are filled and pressurised to a defined level with CO2 and are left under controlled environmental conditions and the time taken for them to lose a set % of their carbonation level is recorded. The test results are then compared to the average CO2 retention time seen for virgin resins. Whilst all results for rPET material showed a reduction in retention time, the shortfall was not viewed as significant enough to impact on the products shelf life.

CO2 retention times

7.67.8

88.28.48.68.8

99.2

25% SC/75%

S93

25% SC/75%

S99

8

25% SC/75%

CB11

E

40% SC/60%

CB11

E

50% SC/50%

CB11

E

25% EC/75%

PC

25% U

RRC/75% C

B11E

40% U

RRC/60% C

B11E

50% U

RRC/50% C

B11E

25% U

RRC/75% La

ser+

40% U

RRC/60% La

ser+

Wee

ks

Avg retention time for Virgin resins

The length of CO2 retention can be influenced by a number of factors such as individual blower characteristics, set-ups and laboratory testing error in addition to the variation


induced by resin changes. In order to reduce these variables to allow for easier comparison all the trials were completed on the same manufacturing line at Wakefield, using the same bottle blower (but with different process technicians) These tests clearly indicate that there is a significant reduction in retained CO2 levels when working with rPET. The average retention time, a combination of a number of virgin resins, is 9.02 weeks. All recycled combinations show a reduction against this benchmark, with Ecoclear losing almost a week of retention time. However other than measurement error, it is difficult to explain why increasing the content of Supercycle from 25% to 50% actually improves retention time.


6.2 Supercycle T2 & T3 trials Based on the T1 results, T2 trials with Supercycle proceeded at 2 CCE sites, East Kilbride & Sidcup. East Kilbride ran a blend of 25% Supercycle with 75% CB11E and Sidcup ran 25% Supercycle with 75% Equipolymers S93. Each trial involved blowing, filling and shipping several hundred thousand bottles. The purpose of these larger scale trials is to check for any process or material variation over several hours of running. There were no significant issues identified in running the material and as such the decision was made to simply convert standard production over to Supercycle. In addition latterly Sidcup also successfully ran 25% Supercycle with 75% Equipolymers S98 in production volumes. 6.2.1 Consumer Feedback analysis of Supercycle Production All TCCC products in the UK have a freephone number for consumers to call in with any issues or complaints. This data is captured and any trends in failure modes are investigated. It also provides excellent data to allow for a direct comparison to be made between product containing recycled content and that which has 100% virgin material. The following table shows all consumer contacts regarding all rPET produced to date and a comparison with virgin PET produced over the same period the year before. Consumer complaint

Sidcup Virgin PET Production Nov ‘04-April ‘05

Sidcup rPET production Nov ‘05 – April ‘06

East Kilbride Virgin PET production Sept ‘04-April ‘05

East Kilbride rPET production Sept ‘05- April ‘06

Past BBE 6 4 Closure issue 1 1 1 Carbonation low

1 3 1 3

Leaker 1 Neck problem 1 Foreign matter 1 3 Off taste 2 8 Damaged 1 Gusher 1 Odour 2 Cut 1

Totals 10 6 7 19 None of the above findings caused a ‘red flag’ investigation, where a trend is seen in a single batch of production requiring an immediate detailed investigation, however there are increases in the areas of off-taste and complaints about low carbonation, which are both higher when run with rPET than virgin. It may be that the original laboratory testing indicating a loss of CO2 retention are being reflected in actual consumer feedback, however it should be noted that the total complaints (6+19 =) 26 relate to ~75M bottles of ‘Coca-Cola’ in the sector or less than 1 failure per million bottles produced. This is well under the CCE specification and hence deemed to be acceptable.


6.2.2 Processability of Supercycle The process settings to blow bottles are combination of blowing cycle times, oven temperature and infrared lamp settings. When successfully combined these variables produce the ‘process window’ through which good quality product is manufactured. The narrower this process window, the harder it is to adjust the settings to overcome any changes. It had been anticipated that due to the complication of running recycled and virgin PET blended together the window would be reduced, however this has proved to be incorrect, when running 25% Supercycle with 75% virgin PET the window is actually larger and the set –up and running is easier, chiefly because energy requirements are lower allowing for more head-room in upward adjustment The only processing problem seen with Supercycle was at Sidcup when Amcor who both produce the preforms and blow the bottles had a processing problem when blending the virgin and rPET together, a valve failed meaning that the resulting preforms were in fact 100% virgin PET, when these were subsequently run on line under rPET processing conditions CCE’s internal test regime caught the problem forcing the line to switch back to virgin resin whilst Amcor investigated the problem, discovered the failure mode and successfully completed the corrective actions. At East Kilbride running series 1 Sidel blowers the power consumption to blow a bottle is actually ~10-20% less than when running virgin PET. There is little direct measurement equipment available on line at East Kilbride to fully quantify these savings, but much anecdotal evidence exists from the process technicians. The target temperature for the preform in blowing is 113oC. To achieve this temperature the blower needs to run at 85-90% when running virgin material this is reduced to 65-70% when running 25% Supercycle preforms in combination with CB11E, a potentially significant saving. However much of this analysis is anecdotal in nature and is best used as a foundation for further work. Sidcup run more modern blowers with a greater capacity to record data. The energy consumption when blowing virgin Equipolymers S98 resin is 147.8 KW hrs - but this falls by 1.55KW hrs when running 25% Supercycle rPET, a ~1% reduction. This level of difference means that the energy requirements of Supercycle although less than virgin offers only a negligible cost saving. This analysis combined with the more positive feedback from East Kilbride, means further investigation is required. 6.3 Conclusions from Supercycle trials Supercycle performed excellently in the trials over a 6 months period, all indications point to a wider processing window, meaning that contrary to expectations running Supercycle at a 25% inclusion rate produces a more forgiving material when blended with CB11E or Equipolymers virgin resins than the virgin resins themselves. Energy usage is ~1% less than when processing 100% virgin resin, offering a small cost saving in electricity costs. There has been a very slight increase in consumer contacts regarding off taste and loss of carbonation, but the complaint levels are very low and will be monitored further.


During the course of the project the full allocation of 500T of Supercycle was consumed producing some 75M bottles. Overall Supercycle has performed excellently over the course of the project. 6.4 URRC T2 trial After successfully running the T1 URRC trial, Wakefield moved towards running a 500,000 sample of preforms in a larger scale T2 trial. Considerable levels of ‘black speck/flake’ contamination were observed during the run and the trial was abandoned after only 100,000 bottles had been produced.

It was decided to repeat the trial by producing a new batch of preforms at Constar under a rigorous inspection regime; this regime indicated that the new production also failed TCCC specification for black specks in the material. The main problem was a number of preforms being contaminated with large black specks/flakes measuring over 2mm in length. Inspection also discovered a number of preforms showing contamination with small black specks

The TCCC ‘black speck/contamination’ specification states that in a sample of 387 preforms (a 10Kg aliquot)

• No preforms are to have specks/flakes with any dimension >2mm in length • Up to 1% of the preforms sampled (ie up to 3 individual preforms) may have

specks with any single dimension between 1mm-2mm in length • Up to 10% of the preforms sampled (ie up to 38 preforms) may have specks

0.5mm-1mm in length Based on the inspection results vs this specification all the remaining preforms from this batch of production were sent to Alpla (a preform converter in Belgium) as they have a camera system capable of inspecting/rejecting contaminated preforms. The preforms were run through Alpla’s camera system and sorted into acceptable preforms (i.e. those specks under 0.5mm in size) whilst rejecting preforms with larger sizes of contamination. This analysis showed that ~3.5% of the preforms produced were rejects with over half of these being due to black speck contamination. The subsequent 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. 6.5 Details of investigational work conducted at Constar on URRC

failures A detailed investigation was conducted at Constar to identify the causes of the black speck contamination problem. A consultant, Prof Ed Kosior was brought in to assist with the work the key findings of his work were:

• The black specks are degraded PET.

• The degraded PET is sourced from the processing equipment.

• The occurrence of the black specks is controlled by the abrasive conditions created during the melting of the PET fed to the extruder.

• RPET blends, process differently to virgin resin blends and scrub the barrel more aggressively under normal conditions.

• Removal of the PET scale on the inside of the barrel greatly improves the reduction in the appearance of the specks.

• The adjustment of the temperature to a “reverse temperature profile” also reduces the incidence of the black specks due to less abrasion on the barrel surface.

• The use of URRC flake will be accompanied by the presence of small particles typically 100 micron in size but their presence should not affect preform acceptability for production.

• The issue of the external contamination should be addressed by Constar to avoid unnecessary losses of preforms mistakenly classified as contaminated.”

In effect there are two types of contamination 1) a low level of very small black specks (sized <0.5mm) in the actual URRC rPET resin as supplied by Cleanaway - at this level, although not perfect, they are well within the TCCC specification for contamination. 2) larger specks (sized from 0.5 up to >2mm) are believed to be caused by degraded/burnt PET which build up in the screw/barrel and manifold of the injection machine before being blown out in the preforms and maybe reduced or even eliminated through cleaning regimes and process control.


6.6 Conclusions from URRC trials URRC is prone to a black speck contamination problem, which maybe exacerbated through the degradation of PET in the preform injection moulding process. The evidence from the T1 trial is that bottles produced with up to a 40% URRC blending rate are completely acceptable if the contamination problem can be overcome. The cost benefits of URRC provide a great incentive to work with both the resin and preform manufacturers further to overcome these issues. It would appear though that the critical area to improve is the converters performance, given that the resin itself is well within tolerance for contamination. The failures due to bursting and the increase in energy usage also need to be investigated, CCE plan to conduct further T2 trials with the preforms produced after the cleaning regime at Constar and if successful move to a T3 trial to consume 500 Tonnes of URRC material at a 25% blending rate over the next several months


7 Conclusions & Next Steps

7.1 Acceptability The approval and testing results from the T1 trials prove that all 3 assessed rPET materials are acceptable for use with 500ml 26g CSD bottles in GB.

• URRC was approved at both 25% & 40% blending rates with virgin material • Supercycle was approved at 25%, 40% & 50% blending rates • Ecoclear was approved at 25%.

In effect when all raw materials are within specification and preform and bottle blowing processing is optimised, an acceptable, safe, consumer friendly more sustainable pack is produced for all rPETs investigated. 7.2 Viability Supercycle has shown it’s self to be viable in terms of ‘processability’. All indications point to a wider processing window, meaning that contrary to expectations running Supercycle at a 25% inclusion rate produces a more forgiving material when blended with CB11E or Equipolymers virgin resins than when running 100% virgin resins. It also appears that there is an energy saving associated with running Supercycle. Pricing and availability of Supercycle will impact on its overall viability as only 17,000T of material are available annually. The trials have highlighted a significant difference in the quality of URRC vs Supercycle in terms of contamination. URRC’s problem with the level of black speck contamination and on line failures has prevented the large scale trialing of the material meaning longer term viability has not currently been fully assessed. Despite these issues URRC does though remain an attractive option due to its good availability and pricing which even in a volatile virgin resin market remains attractive. The project has helped demonstrate that rPET is a viable alternative to virgin PET in the demanding application of CSDs.

• CCE are satisfied that Supercycle could be used at 25% in their CSD bottles subject to the commercial factors of supply and price.

• Although URRC is viable in terms of its availability and pricing further work by

means of a successful large scale trial is required to prove its longer term ‘quality’ viability.


7.3 Next Steps

• The Supercycle trial ended in April 2006 with the consumption of the full 500T of material, further work needs to be undertaken to:

o Fully quantify the energy saving findings o Examine what combinations and percentage blending rate, of Supercycle and

virgin resin give the best results.

• The T2 trial with URRC needs to be repeated and if successful a full T3 trial with 500T of material may be undertaken.

• More investigation is required to fully understand the causes of the lowering of CO2

retention times.

• Examination of (post consumer) feedstock to the recycling process needs to be investigated to understand the level of black speck contamination seen in Cleanaway’s URRC resin.

• Much further work is required by the Convertor to eliminate the causes of black

speck contamination to assure long term quality viability,


8 Appendices

Identify Resin tobe trialed

Is Resin Authorised by GB/IOR BNLF Div or TCCC

AtlantaTCCC for the requiredbottle type?

Go To Protocol C222 days if all testing

required,149 if materialcompatabilitycompleted by

supplier & TCCC

Is Resin in use byCCE in requiredbottle type with

identical preform?

Go to Protocol B137 days if CO2testing required,

58 if no CO2

Go to Protocol A123 days if CO2 testing

required44 days if no CO2

No

Yes

Yes

No

rPET Resin TrialProtocol

Section 1 - Determine ProtocolRequired

Legend

Action on TCCC

Action required byCCE

Decision

See Note 7

7 D

ays

Supplier Timeline

60 D

ays

Min

imum

Joint Timeline

14 d

ays

CCE / TCCCTimeline

Are the blowers/ line the same

?

No

Yes

Go to Protocol A -after CO2 testing

21 days min ifConvertor familiar with

resin.

8.1 Appendix A


Obtain data fromTCCC on use within

system

Is performance dataacceptable ?

Review PurchasingRequirements

No

Yes

PET Resin Trial Protocol Protocol B:

Perform Initialblowing trial

Blowing ResultsAcceptable ?

No

Review PurchasingRequirements

PerformOperationalblowing trial

ResultsAcceptable ?

Yes

Yes

Continue as per Protocol Asecond operational trial

Does testingneed to

be continued for the shelf life ofthe product ?

No

NoHas TCCC

Authorisation beengiven ?

Yes

No

Yes

note 1

note 2

notes 3 & 5

SupplierRequirements

Informed by CCE ofrequirement. Obtain

legislative documents

Does Materialcomply ?

2 D

ays

Is Material newto Converter

Perform Pilot &evaluate injection

trial1 tonne

Blow trial bottles &evaluate

Complete Preproduction trial

6 tonnes

No Yes

Yes

Resultsacceptable

Yes

Review with CCE

No

Continue as per Protocol ACreate material storage

21 D

ays

7 D

ays

93 d

ays

CCERequirements

14 d

ays

testing forPhysicals &

CO2 ifrequired

14 d

ays


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