Processing trials for household film waste

Transcription

1 Summary report Processing trials for household film waste Summary report for demonstration trials assessing novel near-infrared sorting of household plastic film waste Project code: IMT Research date: June - December 2012 Date: September 2013

2 WRAP s vision is a world without waste, where resources are used sustainably. We work with businesses, individuals and communities to help them reap the benefits of reducing waste, developing sustainable products and using resources in an efficient way. Find out more at Written by: Richard McKinlay, Liz Morrish, Shaban Omboke, Beth Ripper and Simon Wilkinson Front cover photography: View into near-infrared sorter used to separate household recyclables WRAP and Axion Consulting believe the content of this report to be correct as at the date of writing. However, factors such as prices, levels of recycled content and regulatory requirements are subject to change and users of the report should check with their suppliers to confirm the current situation. In addition, care should be taken in using any of the cost information provided as it is based upon numerous project-specific assumptions (such as scale, location, tender context, etc.). The report does not claim to be exhaustive, nor does it claim to cover all relevant products and specifications available on the market. While we have tried to make sure this report is accurate, we cannot accept responsibility or be held legally responsible for any loss or damage arising out of or in connection with this information being inaccurate, incomplete or misleading. It is the responsibility of the potential user of a material or product to consult with the supplier or manufacturer and ascertain whether a particular product will satisfy their specific requirements. The listing or featuring of a particular product or company does not constitute an endorsement by WRAP and Axion Consulting cannot guarantee the performance of individual products or materials. This material is copyrighted. You can copy it free of charge as long as the material is accurate and not used in a misleading context. You must identify the source of the material and acknowledge our copyright. You must not use material to endorse or suggest we have endorsed a commercial product or service. For more details please see our terms and conditions on our website at 2

3 Executive summary Plastic film originating from the household waste stream can be challenging to handle, sort and reprocess, especially if it is collected co-mingled at the kerbside. Plastic film can cause problems to Material Recovery Facilities (MRF) as it gets trapped in some equipment, requiring periodical maintenance. Also, due to its light weight and 2D shape it can get mixed with other recyclable streams such as paper, causing contamination. As a result of technical barriers and the added cost of collection, the majority of local authorities in the UK do not target plastic film as part of their collection scheme. To achieve packaging recycling targets in the UK it will be necessary to increase recycling of household plastic film; therefore, it will be essential to identify new approaches for handling and sorting household plastic film waste. New variants on conventional NIR sorters offer the potential to address the technical challenges of sorting plastic film when collected co-mingled at kerbside. This project was commissioned to assess that potential, utilising Pellenc NIR with a Turbosorter, a piece of equipment which introduces an air flow into the system, preventing film and other lightweight materials from moving around on the conveyor, with the aim of more accurate detection and sorting. This report focuses on the sorting trials using the NIR, but also provides an overview of the additional steps required in order to confirm the quality of the film produced, including endmarket application: sourcing of appropriate feedstock for the sorting trials (Casepak MRF, Leicester, UK); testing of the NIR sorters (BS Environnement MRF, Nîmes, France); reprocessing of film to produce polyethylene (PE) pellet (Régéfilms, Abidos, France); and manufacturing test using the resulting PE pellet (CeDo, Telford, UK). Sourcing feedstock for the trial Recyclables from kerbside co-mingled collection were first analysed and processed at Casepak s MRF in Leicester, to produce a 2D fraction containing plastic film (at approximately 6.6%) and fibre materials (mainly paper). A total of approximately 310 tonnes of co-mingled recyclables were processed to produce tonnes of 2D material for the trial. Plastic film sorting using NIR The 2D fraction was subject to a number of trials at the BS Environnement MRF in Nîmes, France to assess the efficiency of separation using the NIR with Turbosorter. The trials demonstrated that the NIR sorters were able to either effectively recover the vast majority (over 95%) of PE film fed into them at a low purity giving a high yield, or produce a high purity PE film product (91%), whilst minimising losses at a lower yield. It was also shown that the NIR can effectively recover polypropylene (PP) if programed to do so. Reprocessing trials using film separated The film output generated during the trials at the BS Environnement MRF was transported to the Régéfilms reprocessing facility in Abidos, South France. Reprocessing test was conducted to determine if good quality PE pellets could be generated from the film. The test demonstrated that: the NIR separators at BS Environnement MRF were able to reduce the contamination of the UK sourced household film to a level at which it was possible to successfully produce PE pellets using the Régéfilms process; Processing trials for household film waste 3

4 no major obstacles were encountered during processing and the film handled in a comparable manner to Régéfilms standard household film infeed, although at a lower throughput rate; the lower throughput rate was due to the absence of agricultural film, which is normally used by Régéfilms to increase the bulk density and reduce overall contamination levels; and the PE pellet produced was tested and found to be of a high quality and suitable for use in manufacturing of end-products. Laboratory analysis showed that the pellet met Régéfilms product specification for moisture, Melt Flow Index (MFI) and density; the lack of surface defects indicated low gas content. The PE pellet was then transported to the CeDo manufacturing facility in Telford, UK. Manufacturing tests were carried out to confirm the quality of the PE pellets; refuse sacks were chosen to be produced to allow a direct comparison with the refuse sacks produced by CeDo, using C&I and agricultural film. It was found that the refuse sacks manufactured were of a high quality, with properties comparable to those produced using CeDo standard pellet. This demonstrates that the NIR sorters successfully and effectively separated the household PE film from other recyclables, allowing for the production of the high quality film. Economic assessment using NIR to replace hand sorting operations in MRFs An economic assessment suggests that using NIR sorters of the type tested, in UK MRFs processing household plastic film from co-mingled kerbside collection may be more beneficial than hand sorting this fraction; this is attributable primarily to the significantly reduced operating cost of the NIR sorters. This indicative analysis is useful for MRF operators who are currently using hand picking and are seeking to replace this operation with NIR sorters. This assessment can also be used to inform the initial design stage of a new build MRF when considering the feasibility of hand picking and NIR sorting for film streams. It should be advised that this assessment has been conducted on the assumption that suitable buyers for all of the material produced can be secured. In order to ensure that an accurate estimate of the economic viability of using NIRs is conducted for a specific site, it is recommended that a bespoke assessment is conducted prior to any investment decisions being made. This assessment should take into account any site specific issues, such as composition of infeed material and material price data trends. Overall summary The trials demonstrated that the tested NIRs with Turbosorters were able to effectively separate the majority of household PE film (over 95%) from the 2D fraction of a kerbside comingled collection at a low purity giving a high yield, or produce a high purity PE film (91%) product, whilst minimising losses at a lower yield. It was also shown that the NIRs can effectively recover PP if programed to do so. The resulting PE film could be successfully reprocessed through existing facilities to produce a high quality PE pellet suitable for end-market application (i.e. refuse sacks). It must be noted that this project did not intend to find an alternative feedstock to be used for the production of refuse sacks, which already have high recycled content; and only meant to allow technical comparison with existing production. If this or other end-markets were to be pursued, it is recommended large scale production trials to examine the quality and consistency of film outputs from a wider range of sources, along with retailer and customer perception testing to examine the consistency of outputs and saleability. The economic assessment suggests that using this variation of NIR sorters in UK MRFs processing kerbside co-mingled recyclables is more beneficial than hand sorting; this is Processing trials for household film waste 4

5 attributable primarily to the significantly reduced operating cost of the NIR sorters. It is recommended that bespoke economic assessments are conducted prior to any investment decisions being made, taking into account any site specific issues, such as composition of infeed material, material price data trends and the security of end markets for process outputs. Processing trials for household film waste 5

6 Contents 1.0 Introduction Background Scope of work Description of the technology used in the project Generation of feedstock for the sorting trial Source of feedstock Processing of feedstock to generate 2D waste stream Compositional analysis Transport of 2D feedstock Assessment of 2D feedstock Methodology for the trials Trial equipment set-up at BS Environnement Description of tests conducted Test 1: Preliminary equipment assessment Test 2: Generation of PE film feedstock for onward reprocessing at Régéfilms Test 3: Assessment of PE film separation efficiency Test 4: Assessment of PE and PP film separation efficiency Mass balance methodology Compositional analysis methodology Sample size calculator Representative sampling Compositional analysis exercise Results Test 1: Preliminary equipment assessment Mass balance analysis around Mixer Test 2: Generation of PE film for Régéfilms Test 3: Assessment of PE film separation Test 4: Assessment of PE and PP film separation Comparison of results from Test 3 and Test Assessment of NIR A performance Assessment of NIR D performance Commentary on NIR A and NIR D performance Generation of PE pellet Methodology Results Conclusions Manufacture of end-product Process description Methodology Results and conclusions Economic assessment Overall conclusions NIR sorting Reprocessing stage using film separated by the NIRs Economic assessment: Use of Pellenc NIR to replace hand sorting operations 57 Appendix 1 Additional information about the sorting technology assessed Appendix 2 Details of Local Authority kerbside collection schemes used in the trial Appendix 3 Error propagation Appendix 4 Process Flow Diagrams Processing trials for household film waste 6

7 Appendix 5 Mass Balance Appendix 6 Composition Analysis List of Figures Figure 1 Flow diagram with the different phases of the project Figure 2 Schematic of Pellenc NIR with Turbosorter Figure 3 Unprocessed material from WMDC kerbside co-mingled recycling collections Figure 4 Unprocessed material from SHDC kerbside co-mingled recycling collections Figure 5 Loading of co-mingled kerbside recyclables for processing at the Casepak MRF Figure 6 The 2D feedstock generated was diverted to an exterior covered bunker Figure 7 Compositional analysis area used at Casepak MRF Figure 8 UK feedstock segregated at the BS Environnement MRF Figure 9 BS Environnement trial process flowsheet Figure 10 Fibre bales prepared for weighing Figure 11 Weighing of individual film bale at the BS Environnement weighbridge Figure 12 Samples collected for compositional analysis Figure 13 NIR A eject (stream 11) sourcing point Figure 14 Example of mixed plastic film (left) and fibre (right) Figure 15 Example of composite cartons (left) and other recyclables (right) Figure 16 Example of textiles found in the waste stream (left) and fines (right) Figure 17 Set-up of compositional analysis area Figure 18 Manual assessment of polymer types during hand sorting of trial outputs Figure 19 Polymer testing using NIR hand held equipment Figure 20 BSE mass balance using data from Test Figure 21 Snapshot of Mixer 1 material flow Figure 22 Comparison of NIR A performance with increasing throughput Figure 23 Composition of NIR feed and product streams during Test Figure 24 Composition of the NIRs feed and product streams in Test Figure 25 Performance of NIR A in Test 3 and Test Figure 26 Performance of NIR D in Test 3 and Test Figure 27 Flow diagram of Régéfilms process Figure 28 PE pellet produced from UK household film Figure 29 Recipe used for comparison of PCR Figure 30 Schematic of film blowing line Figure 31 Blowing of PE film during CeDo trial Figure 32 Rolls of refuse sacks made using various quantities of PCR Figure 33 2D/3D separation mass balance for both options Figure 34 Mass balance for hand picking of film from 2D fraction Figure 35 Mass balance for NIR sorting of film from 2D fraction Figure 36 Casepak MRF block flow diagram and mass balance Figure 37 Normal operating flow at BS Environnement MRF List of Tables Table 1 Composition analysis of the 2D product fraction produced at Casepak MRF Table 2 Error limits on final 2D product composition Table 3 Description of the functional operating units used during the trials Table 4 Summary of Test Processing trials for household film waste 7

8 Table 5 Summary of Test Table 6 Summary of Test Table 7 Summary of Test Table 8 Sub-sample analysis categories Table 9 Film identification characteristics Table 10 Performance of disc screen in Test Table 11 Split of products from the disc screen during Test Table 12 Mass balance on NIR A, C and D for the Test Table 13 Quality, Reject and purity for NIR A and D in Test Table 14 Mass balance variation around Mixer Table 15 Mass balance of whole plant for Test Table 16 Mass balance on NIR A and D for Test Table 17 Q and R of NIR A and D for Test Table 18 Mass balance on NIR A and D for Test Table 19 Q and R of NIR A and D for Test Table 20 Performance of NIR A in Test 3 and Test Table 21 Performance of NIR D in Test 3 and Test Table 22 Mass balance for Régéfilms trial Table 23 Physical properties of PE pellets Table 24 PCR content and thickness of refuse sacks made using trial PCR Table 25 Product/feed values used for economic assessment Table 26 Annual costs and revenues for each film sorting option Table 27 NPV for each option Table 28 Mass balance for Test 1: Preliminary equipment assessment Table 29 Mass balance for Test 3: Assessment of PE film separation Table 30 Mass balance for Test 4: Assessment of PE and PP film separation Table 31 Composition analysis for Test 1: Preliminary equipment assessment Table 32 Composition analysis for Test 3: Assessment of PE film separation Table 33 Composition analysis for Test 4: Assessment of PE and PP film separation Processing trials for household film waste 8

9 Glossary 3D 2D BPF C&D C&I HDPE kg kg/h LDPE LLDPE MDPE MFI MRF NIR PCR PE PET PP PS Purity PVC Q R SHDC t t/h WMDC WRAP Three dimensional materials (e.g. plastic bottles, aluminium cans) Two dimensional materials (e.g. paper, film) British Plastics Federation Construction and Demolition Commercial and Industrial High Density Polyethylene Kilograms Kilograms per hour Low Density Polyethylene Linear Low Density Polyethylene Medium Density Polyethylene Melt Flow Index Material Recovery Facility Near-infrared Post-consumer recyclate Polyethylene Polyethylene terephthalate Polypropylene Polystyrene Proportion of desirable product in an output stream Polyvinyl chloride Quality - measure of how good a NIR unit is at separating the target material Reject - measure of how good a NIR unit is at separating the non-target material South Holland District Council Tonnes Tonnes per hour Walsall Metropolitan District Council Waste & Resources Action Programme Processing trials for household film waste 9

10 1.0 Introduction 1.1 Background It is estimated that over 550k tonnes of household waste plastic packaging film is produced in the UK each year. Of this, around 50% is considered to be polyethylene film 1. Film waste handling, sorting and processing is technically challenging, especially when the film originates from local authority collected waste stream, as it tends to be collected together with other recyclables at the kerbside. Plastic film can cause problems to Material Recovery Facilities (MRFs) as it can become trapped in equipment leading to operational down time and increased maintenance costs. Also, due to its lightweight nature and 2D shape, film can get mixed with other recyclable streams such as paper, causing contamination. As a result of technical barriers and the added cost of collection the majority of local authorities in the UK do not target plastic film as part of their collection scheme. To increase recycling of household film in the UK and achieve current recycling targets, it will be essential to identify new approaches for handling, sorting and processing household film waste. 1.2 Scope of work This project was commissioned to assess the potential that new variants on conventional near infra-red (NIR) sorters currently used outside of the UK, offer to address the technical challenges of sorting plastic film when collected co-mingled at kerbside. A novel approach to NIR sorting, manufactured by Pellenc Selective Technologies, was identified to be suitable for the proposed trials during the project. The new approach differs from conventional NIRs in that it uses a Turbosorter, an additional equipment which introduces an air flow into the NIR, preventing film and other lightweight materials from moving around on the conveyor, with the aim of more accurate detection and sorting. The aim of the project was to determine whether UK household film collected co-mingled at kerbside could be successfully sorted at a MRF using Pellenc near-infrared (NIR) sorting equipment. In addition to measuring the sorting efficiencies of the NIR, the project analysed the economics of the technology and barriers to adoption and implementation in the UK. The project was delivered in several key phases: identification and procurement of suitable feedstock for the sorting trial; testing of NIR film separation efficiencies (mass balance and compositional analysis) at BS Environnement MRF, France; further separation, cleaning and extrusion of film output into PE pellets at Régéfilms, France; and manufacture of end-product from the reprocessed PE pellet product at CeDo, UK. This report focuses on the generation of feedstock and subsequently separation using the selected NIR. The information related to the additional phases including extrusion into pellets and manufacturing of an end-product will be summarised as they were only carried out to prove the quality of the separation trials. Figure 1 shows a flow diagram of the project with the trials that were undertaken and the material produced at each stage. 1 Valpak PlasFlow 2017 Report (2013) Processing trials for household film waste 10

11 Figure 1 Flow diagram with the different phases of the project Processing trials for household film waste 11

12 2.0 Description of the technology used in the project The technology used during the trial was a Pellenc Mistral NIR with a Turbosorter. NIR sorting technology works by illuminating objects on a conveyor belt and detecting the wavelength of reflected light. Depending on the type of material, different wavelengths of light are reflected and a special sensor above the belt can determine the material type from this fingerprint of wavelengths. The equipment then instructs a row of air jets further down the conveyor belt to fire out any material that it has been programmed to search for. The material blown away by the air jets is referred to as the eject fraction, whereas the material that is unaffected is called the reject/drops fraction. The machine can be programmed to eject the target material (the desirable fraction) or the non-target fraction (the undesirable fraction). NIR technologies are well established in UK MRF operation and can be supplied by a range of different companies. The unique aspect of the NIR used in this project is that it is designed to retain the position of the film on the conveyor belt. As film is so lightweight, it can easily be blown about and change position on the conveyor once it has been detected. If this happens the air jets may not target the correct material, resulting in not all of the detected film being ejected. This can mean that the film contaminates the desirable/target fractions. This issue was addressed by covering the conveyor as it enters the NIR and generating an air flow which moves at the same speed as the conveyor. This effectively pins the feed material to the conveyor, preventing lightweight items from rolling or being blown about. The objective of this airflow is to improve the accuracy of the NIR sorter and improve separation efficiencies where lightweight items, such as plastic films, are found in the feed material. This system is known as a Turbosorter and a schematic of the equipment is given in Figure 2 (more information on the NIR sorter can be found in Appendix 1). Figure 2 Schematic of Pellenc NIR with Turbosorter NIR technology cannot be used to separate different densities of PE, as they all share the same infrared spectrum. For this reason the NIR sorters produce a PE film fraction containing HDPE, LDPE, LLDPE and MDPE, which can then be recycled into a PE pellet. Processing trials for household film waste 12

13 3.0 Generation of feedstock for the sorting trial The demonstration trials to test the Pellenc NIR equipment were hosted at a MRF in France. In order to ensure the relevance of the trials to the UK market, it was essential to test the equipment s performance when processing UK sourced household recyclable material, as the composition of household waste in France differs considerably to that of household waste in the UK. Environmental legislation prohibits the transport of mixed municipal waste from the UK to France. As a result, it was necessary to collect suitable feedstock in the UK and conduct an initial processing before the material could be exported for the trial under green list controls 2, in compliance with relevant legislation. The objective of this phase of the project was to process material from UK co-mingled kerbside collections and separate 3D fraction, such as cans and plastic bottles, from the 2D fraction, comprised of mixed paper and films. The 2D material would then be suitable for export to France as a feedstock for the trial. This would not adversely affect the realism of the trial, as 2D and 3D materials are typically separated during routine MRF operations prior to further material sorting. Generation of the 2D feedstock was conducted at Casepak s MRF in Leicester, UK, by adapting its existing waste separation processes (see Section 3.2 for further details). The MRF currently processes 26 tonnes of dry mixed recyclables per hour (approximately 150,000 tonnes per annum), including household plastic film. The site is licensed to process up to 360,000 tonnes of material each year 3. Based on Casepak s assessment of the typical paper and film content of its feed material, it was estimated that approximately 150 tonnes of 2D material would be required in order to meet the objectives of the subsequent NIR processing trials in France. 3.1 Source of feedstock Feedstock was sourced from household kerbside co-mingled collections from Walsall Metropolitan District Council (WMDC) and South Holland District Council (SHDC). Material specified for collection from these local authorities is detailed in Appendix 2. Images of the unprocessed, mixed dry recyclables are shown in Figure 3 and Figure 4. 2 Environment Agency (2012), Green list controls, 3 Casepak (2012), Recycling Excellence, Collection & Processing Facility, Processing trials for household film waste 13

14 Figure 3 Unprocessed material from WMDC kerbside co-mingled recycling collections Figure 4 Unprocessed material from SHDC kerbside co-mingled recycling collections 3.2 Processing of feedstock to generate 2D waste stream Processing the co-mingled kerbside recyclables to generate the 2D feedstock for the trials involved several procedural and plant modifications to be undertaken by Casepak. Film, which is typically removed from the mixed dry recyclable stream through a series of hand picking stations and optical sorting units, was allowed to pass through the MRF with other recyclable materials. The existing optical sorters at the MRF were programmed to enable plastic films to remain in the paper streams. In addition, conveyor diverts were used to recombine the mixed paper and news & pams (newspaper and pamphlets) lines and to discharge material to a covered storage bunker outside of the MRF building. Processing trials for household film waste 14

15 During processing, large pieces of film (e.g. large refuse sacks) were manually removed at the front end picking station to reduce blockages and potential damage to downstream equipment. This film material was blended in with the final 2D material at the end of the trial to increase the quantity of film for the subsequent trials and to ensure that the feedstock processed was representative of the original material received at the Casepak MRF. Figure 5 shows the loading of co-mingled kerbside recyclable materials at the MRF. Figure 6 shows the 2D feedstock material being diverted to an exterior covered bunker. Figure 5 Loading of co-mingled kerbside recyclables for processing at the Casepak MRF Figure 6 The 2D feedstock generated was diverted to an exterior covered bunker Processing trials for household film waste 15

16 3.3 Compositional analysis Compositional analysis was conducted on samples of the 2D output material to assess the film content and to verify that the film content was sufficiently high to meet the requirements of the subsequent processing trials in France. During the course of the assessment three samples, weighing approximately kg each, were taken from different parts of the output pile and were hand sorted into film and non-film material categories. Figure 7 shows the compositional analysis work being undertaken at Casepak. Figure 7 Compositional analysis area used at Casepak MRF A total of 478 kg of 2D material was analysed. The results of the indicative compositional analysis are shown in Table 1. Table 1 Composition analysis of the 2D product fraction produced at Casepak MRF Sort 1 Sort 2 Sort 3 Average Amount sorted (kg) n/a Film (weight %) 3.5% 6.6% 8.8% 6.3% Non-film (weight %) 96.5% 93.4% 91.2% 93.7% In total, tonnes of 2D material was generated at the Casepak MRF, including 413 kg of oversized plastic film initially removed by the hand pickers, which was blended back into the final product. The final film composition of the bulk load was estimated to be approximately 6.6%. With a 95% confidence level in the results, the estimated film and non-film content of the 2D material is shown in Table 2 along with the error limits within a 95% confidence. An explanation of how the errors have been estimated is given in Section 4.4. Processing trials for household film waste 16

17 Table 2 Error limits on final 2D product composition Component Composition Error Film 6.6% ± 0.3% Non-film 93.4% ± 0.9% At this level of confidence and error limits, the film content of the material sent to BS Environnement lies between 9.19 tonnes and 9.63 tonnes. This was considered to be sufficient for the subsequent processing trials in France, based on the minimum tonnage that would be required for subsequent phases (i.e. reprocessing and manufacturing). 3.4 Transport of 2D feedstock The processed 2D material was loaded into 92 cubic metre walking floor vehicles and the mass of each load was recorded at the weighbridge at the Casepak MRF. Based on belt weight measurements, a total of 310 tonnes of material from WMDC and SHDC were processed during approximately 12 hours (excluding planned stoppages and plant breakdown). The feed material was processed at a rate of 25.2 tonnes per hour (typical plant processing speeds at the Casepak facility are 26 tonnes per hour). 3.5 Assessment of 2D feedstock The 2D material generated at the Casepak MRF was transported to the BS Environnement MRF in Nîmes, France, for the sorting trial. The 2D material was segregated on site at BS Environnement to mitigate the risk of contamination by local waste streams being collected from Nîmes (see Figure 8). The material was subjected to a visual examination and it was noted that the feedstock for the trial also contained some contaminants, including textiles and compressed dry recyclables like drinks cans. The breakdown of the composition was not calculated. Figure 8 UK feedstock segregated at the BS Environnement MRF Processing trials for household film waste 17

18 4.0 Methodology for the trials 4.1 Trial equipment set-up at BS Environnement The BS Environnement MRF is equipped to process both 2D and 3D household waste materials. However, given that the feedstock prepared at Casepak MRF was mainly 2D, modifications were made to the plant to bypass processing equipment typically used to sort 3D material. The process plant set-up used for the trials is shown in Figure 9. The full process flow set-up of the BS Environnement MRF is available in Appendix 4. Table 3 provides a description of the functional operating units shown in Figure 9. Table 3 Description of the functional operating units used during the trials Unit of operation Hand pick Overband magnet Disc screen NIR A NIR C Trial operational description Manual removal of large pieces of cardboard, large film, black film and other contamination; this was kept separate from the final product stream Recovery of ferrous material from the infeed stream Separation of the incoming material into 2D, 3D and fines fractions Set to eject all plastic film from fibre and other material Set to eject all material in order to minimise the material going to stream 10 Mixer 1 A mixing point for stream 10 and 11 NIR D Set to eject PE and PP film for test 1 and 4 Set to eject PE only for test 2 and 3 Processing trials for household film waste 18

19 Figure 9 BS Environnement trial process flowsheet Processing trials for household film waste 19

20 4.2 Description of tests conducted In order to determine the separation efficiency of the NIR sorters and generate sufficient film for subsequent film reprocessing, four different tests were conducted at the BS Environnement MRF as detailed below: Test 1: preliminary equipment assessment (low volume test to ensure that the equipment was correctly configured); Test 2: large scale processing of 2D feed material to generate a sufficient quantity of film suitable for subsequent reprocessing at Régéfilms; Test 3: test to measure the performance of NIR A in recovering all plastic film and the performance of NIR D in recovering PE film only (both HDPE and LDPE); and Test 4: to measure the performance of NIR A in recovering all plastic film and the performance of NIR D in recovering PE film (both HDPE and LDPE) and PP film Test 1: Preliminary equipment assessment This was a preliminary test to ensure that the plant equipment was correctly configured and that the functional operating unit requirements detailed in Table 3 were being achieved. A summary of Test 1 is shown in Table 4. Table 4 Summary of Test 1 Objective NIR A setting NIR D setting Trial time Amount processed Average throughput To determine the approximate product yield and quality being generated by the BS Environnement MRF equipment to ensure correct operation during subsequent trials Eject all plastic film (HDPE, LDPE, PP, PS and PVC) Eject PE film only 10 minutes 1,394 kg 8.24 t/h Test 2: Generation of PE film feedstock for onward reprocessing at Régéfilms Test 2 was the main test involving the processing of the majority of the 2D feedstock material. This test led to the generation of a PE film product, containing both HDPE and LDPE, that would be suitable for further reprocessing at Régéfilms. Table 5 provides a summary of Test 2. Processing trials for household film waste 20

21 Table 5 Summary of Test 2 Objective NIR A setting NIR D setting Trial time Amount processed To generate a sufficient quantity of PE film suitable for use in subsequent reprocessing trials at Régéfilms Eject all plastic film (HDPE, LDPE, PP, PS and PVC) Eject PE film only 13 hours 106,814 kg Average throughput 8.22 t/h Test 3: Assessment of PE film separation efficiency Test 3 assessed the individual performance of NIR A and D when producing a pure PE film product, such as that required for Régéfilms. The NIR settings were the same as for Test 2, as shown in Table 6. Table 6 Summary of Test 3 Objective NIR A setting NIR D setting Trial time Amount processed Average throughput To measure the performance of NIR A in recovering all plastic film and the performance of NIR D in recovering PE film only (both HDPE and LDPE) Eject all plastic film (HDPE, LDPE, PP, PS and PVC) Eject PE film only 2 hours 16,328 kg 8.16 t/h Test 4: Assessment of PE and PP film separation efficiency This test was undertaken to assess the performance of the Pellenc NIRs in recovering both PP and PE film from other film and materials. This test also allowed for the examination of the likely maximum PP content to be present in the PE film and how this may affect the purity of final product. The test details are summarised in Table 7. Processing trials for household film waste 21

22 Table 7 Summary of Test 4 Objective NIR A setting NIR D setting Trial time Amount processed Average throughput To measure the performance of NIR A in recovering all plastic film and the performance of NIR D in recovering PE film (both HDPE and LDPE) and PP film Eject all plastic film (HDPE, LDPE, PP, PS and PVC) Eject PE and PP film 2 hours 10 minutes 21,284 kg 9.82 t/h 4.3 Mass balance methodology A mass balance is an assessment tool, which provides information about the total quantity of material processed and the amount of material being sorted into eject and reject fractions at each stage of the process. A mass balance was carried out for all four tests described in Section 4.2. In Test 1, the total quantity of material collected in each of the output product bunkers was relatively small. The output fractions were placed into separate bins provided by BS Environnement and weighed on small scales, with an error of ± 0.5 kg. For the remaining tests, where larger quantities of material were processed, it was necessary to use an alternative methodology; after completion of each test, material collected in each of the output product bunkers was treated as follows: all the material was baled and clearly labelled (Figure 10); the bales were loaded on to a flatbed truck, which was driven on to the weighbridge for weighing (Figure 11). The weighbridge scale had an error of ±20 kg; the weight of the truck and bales was recorded, and the weight of the truck subtracted from the total weight to give the weight of the bales only; and the material was then off loaded and the procedure was repeated for the other streams for all tests. Processing trials for household film waste 22

23 Figure 10 Fibre bales prepared for weighing All of the bales of film produced for reprocessing at the Régéfilms site (Test 2) were individually weighed at the BS Environnement weighbridge as shown in Figure 11. Figure 11 Weighing of individual film bale at the BS Environnement weighbridge Processing trials for household film waste 23

24 4.4 Compositional analysis methodology This section discusses the tools and methodology used in carrying out composition analysis of the output product streams Sample size calculator A model was developed by Axion using standard statistical techniques to determine the sample size required for assessment and the resulting accuracy of results at the desired confidence interval. The statistical model required the input of the following information: the average weight of an item (e.g. a piece of plastic film); an estimated stream composition; the desired error in the stream composition. This is the tolerable error of the estimated composition; and the confidence level in the stream composition (0% low confidence 100% high confidence). A low confidence interval indicates that we were not sure of the composition of the material entered into the calculator and vice versa for high confidence intervals. If the predicted sample size was too large for practical analysis, a more realistic sample size was entered to enable a revised calculation of the resulting errors in the compositional analysis results; in cases where a smaller sample size had to be assessed, the likely error on the results is larger. At the end of a product stream composition analysis, the actual final composition recorded was used to replace the estimated composition, to obtain a more accurate indication of the likely error in the final compositions recorded Representative sampling Compositional analysis was conducted on streams 9, 11, 12, 14 and 15 (see Figure 9) for tests 1, 3 and 4 only. Composition analysis was not conducted for Test 2 as the same NIR settings for Test 3 were used. For each output stream in each test, representative sample sizes determined by the sample calculator were taken for assessment. For streams 9, 12, 14 and 15 in each test, representative samples were obtained by spreading a tarpaulin in the output product bunker and collecting material for five minutes. If the material collected within the five minute period was not sufficient, the same procedure was repeated until the sample weight was equal to the chosen sample size from the sample size calculator. The samples were then bagged (see Figure 12) and set aside for compositional analysis. Processing trials for household film waste 24

25 Figure 12 Samples collected for compositional analysis As stream 11 was an intermediate stream (i.e. located between two pieces of operating equipment), samples collected at this point could only be collected on an instantaneous basis due to accessibility restrictions brought about by the plant layout. Here, the samples were collected by manually diverting the NIR A eject fraction for 30 seconds at three different times during the test. The collection of material was timed and the product weighed for throughput estimation and compositional analysis for all three tests. It is important to note that instantaneous throughput and composition analysis are not as reliable as they do not enable fully representative samples to be assessed. However, understanding the composition of stream 11 was important to gain insight into the mass flow of each component around Mixer 1, enabling performance analysis of both NIR A and NIR D. Figure 13 shows the point at which samples for stream 11 were collected. Figure 13 NIR A eject (stream 11) sourcing point Processing trials for household film waste 25

26 For the identified streams (including stream 11), the quantities of material for analysis ranged from 30 kg for the plastic film stream (stream 14) to 150 kg for the fibre rich stream (streams 9 and 12) Compositional analysis exercise Once samples were collected from each test, the compositional analysis for each product stream was carried out in two stages. The first stage involved separating materials within the sample into the categories identified in Table 8 and the second stage involved a more detailed assessment of the plastic film fraction, which was further separated into different polymer types. Table 8 Sub-sample analysis categories Categories Examples Plastic film HDPE, LDPE, LLDPE, PP, black film, other films (metalised - PE), other films (non-metalised) Fibre Composite cartons Other recyclables Waste Fines Paper, card, newspapers, magazines Juice carton, milk cartons Steel and aluminium cans, plastic bottles, other recyclables Black plastic films, textiles, non-recyclable items < 50mm material Figure 14, Figure 15 and Figure 16 show examples of the different material categories given in Table 8 that were identified during the trials. Figure 14 Example of mixed plastic film (left) and fibre (right) Processing trials for household film waste 26

27 Figure 15 Example of composite cartons (left) and other recyclables (right) Figure 16 Example of textiles found in the waste stream (left) and fines (right) During the first stage analysis, the following procedure was used to separately analyse every product stream in each test: a sub-sample of the collected product stream, weighing 5 10 kg, was placed onto the sorting tables shown in Figure 17; The sub-sample was then separated into the identified categories (Table 8): the separated fractions were then weighed and entered into Axion s statistical composition analysis model 4 ; following completion of the sub-sample compositional analysis, the plastic film fraction was then stored for the second stage analysis of polymer type examination; and the above steps were repeated until a consistent composition was reflected by the model. The model demonstrated that for each product stream, the compositional analysis data collected was sufficiently representative following the analysis of six to eight sub-samples. 4 Axion s compositional analysis model is a statistically robust tool which measures the variance in overall sample composition with each additional sub-sample analysed. By monitoring this variance, it is possible to determine when a sufficient number of sub-samples have been analysed to provide statistically robust results. In addition to providing confident results with error limits, the tool also reduces the time and labour required to complete the analysis. Processing trials for household film waste 27

28 Figure 17 Set-up of compositional analysis area Upon the completion of the first stage compositional analysis, all the plastic film collected from the sub-samples of each product stream was further analysed to provide an indicative assessment of the polymer types present in the film fractions. There is no established scientific method for manually identifying different film polymer types accurately, unless conducting laboratory tests such as flame tests 5. As flame tests were not a viable analysis tool during the tests, personnel extensive experience in manual film identification was used to distinguish the different polymer types in the material processed - see Figure 18. The assessment was conducted by evaluating various physical properties of the polymers including: noise characteristics; visual assessment; texture; and the tear behaviour of the film. Further details on the sorting criteria are provided in Table 9. 5 Bluewater Recycling Association, Polymer Identification, Processing trials for household film waste 28

29 Table 9 Film identification characteristics Polymer type Characteristics 6 HDPE LDPE LLDPE PP Metalised film (PE) Black film Other film Crinkly noise, typically used by supermarkets for singlet bags (e.g. carrier bags and t-shirt bags) Smooth feel and soft tear (e.g. recycling collection bags and bubble wrap) Stiff feel, typically used to wrap a four/six pack of soft drinks (e.g. stretch wrap and dry cleaning film) Crinkly noise, easy to tear and typically used in packing of sweets (e.g. most woven bags and cigarette over wrap) Have shiny surfaces, such as crisp packets and chocolate wrappers (e.g. potato chip bags) Black in colour (e.g. domestic bin bags) Other plastic film that did not exhibit the above properties and could not be easily identified. This includes composite films made of several layers Figure 18 Manual assessment of polymer types during hand sorting of trial outputs 6 PlasticBagRecycling.Org, Determining the type of plastic film, Processing trials for household film waste 29

30 In situations where the polymer types could not be easily identified by the above characteristics, an NIR hand held tool (Figure 19) provided by Pellenc was used to more accurately identify the polymer type. Using an NIR gun for each item is more time consuming, and as a result, was only used in cases where the manual sort was uncertain. Figure 19 Polymer testing using NIR hand held equipment Processing trials for household film waste 30

31 5.0 Results The results of the four tests, along with a comparison between Test 3 and Test 4 are detailed within this section. To assess the performance of the NIRs, the following values were calculated: Quality (Q) Quality, referred to as Q from this point onwards, is considered as a measure of how good a unit is at separating the target material (in this case PE/PP film) into the valuable product stream. It is calculated by using the following formula: A high Q value is desirable, representing a high efficiency in separating the target material into the product stream with little target material being lost to the non-product stream. A low Q value means that a large quantity of target material is being lost into the non-target stream. It is important to note that, Q is a measure of yield not product purity. Reject (R) Reject, referred to as R from this point onwards, is a measure of how good a unit is at separating the non-target material into the non-product (waste) stream. It is calculated using the following formula: A high R value is desirable, meaning that the majority of non-target material is separated into the non-product stream. Conversely, a low R value shows that a significant proportion of the non-target material has been sorted into the target stream. High Q and R values indicate that separation equipment in question is working in a good capacity, whilst low Q and R values show poor equipment performance. Purity Purity is the proportion of desirable product in an output stream. Purity can be calculated in two different ways. It can be calculated using the following formula: Alternatively, the purity can be calculated by the summation of the composition of the target material in the product stream: A high purity value is desirable and shows that the product stream contains predominantly target material. A low purity value indicates that the product stream contains predominantly non-target material and is of inferior quality. Therefore, even if the value R is high, there could still be a relatively high proportion of non-target material entering the product stream, leading to a low purity. Processing trials for household film waste 31

32 Error propagation For all the composition analysis that was undertaken, the errors were calculated using Axion s in-house sample calculator, discussed in Section To convey these errors for the Quality (Q), Reject (R) and Purity, the rules of error propagation were applied. Determining the errors in final performance analysis values enabled a confident judgement of the performance of the NIR s tested at the BS Environnement trial to be reached. The rules of error propagation 7 applied to all the samples analysed were a) addition or subtraction and b) multiplication or division. Details on the calculation of each rule can be found in Appendix 3. These two rules were applied to all the composition analysis that was carried out during the trials. They were also applied to all the calculated compositions in the mass balances. The errors were conveyed in the final Quality, Reject and Purity results for each NIR whose performance was analysed improving the confidence in the results. This can be seen in the following sections. 5.1 Test 1: Preliminary equipment assessment The purpose of Test 1 was to obtain initial estimates of the performance of the equipment. For this reason the trial was conducted over a short period of time (10 minutes) and as a consequence the results are not wholly representative of the efficiency of the equipment, but provide a preliminary indication of whether or not the plant was operating properly. A full mass balance was conducted and the data can be found in Table 28, Appendix 4. In the following section the most relevant results of the trial are presented. The mass balance over the disc screen and composition for each stream is given in Table Harvard University, Rules for Error Propagation, Processing trials for household film waste 32

33 Table 10 Performance of disc screen in Test 1 Throughput (kg/h) Disc screen Composition of stream Target PE film in feed % Other materials in feed 7, % Total in feed 7, % Target PE in film 2D fraction % Other materials in 2D fraction 2, % Total in 2D fraction 2, % Target PE film in 3D fraction % Other materials in 3D fraction 3, % Total in 3D fraction 3, % Target PE film in fines % Other materials in fines 1, % Total in fines 1, % It can be seen that although the material fed into the BS Environnement MRF had already been separated into a 2D fraction, the disc screen still removed a significant proportion of the feed into the 3D stream. Table 11 shows that 44.5% of the material fed into the disc screen was recovered as 3D and 19.3% as fines. Since such a high proportion of the feed material was classified as 3D, and an on-site visual assessment of this stream indicated a high proportion of 2D items, it suggests the disc screen was not operating at optimum efficiency. However, since the purpose of Test 1 was to assess the performance of the NIR separators, this was not a key concern for the trial. Table 11 Split of products from the disc screen during Test 1 Percentage of feed reporting to each stream 2D material 36.2% 3D material 44.5% Fines 19.3% Table 12 shows the throughput and compositional data for each of the three NIR sorters used. Figure 20 gives the mass balance on the flow diagram. Processing trials for household film waste 33

34 Table 12 Mass balance on NIR A, C and D for the Test 1 Target PE film in feed Other materials in feed Total in feed Target PE in film eject Other materials in eject Total in ejects Target PE film in drops Other materials in drops Total in drops Throughput (kg/h) NIR A NIR C NIR D Composition Throughput (kg/h) Composition Throughput (kg/h) Composition % % % 3, % % % 3, % 2, % 1, % % % % % 2, % % % 2, % % 8 0.3% 4 1.4% % 2, % % % 2, % % 1, % Processing trials for household film waste 34

35 Figure 20 BSE mass balance using data from Test 1 Throughput: 58 kg/h PE film content: 0% Ferrous 4 Throughput: 3468 kg/h PE film content: 5.7% Feed (2D material from Casepak) Throughput: 8241 kg/h PE film content: 7.5% 1 Hand Pick 2 Large Cardboard and Film Throughput: 370 kg/h PE film content: 10% 3 Overband Magnet Fines 6 5 Disc Screen 3-D fraction 7 NIR C 2-D fraction Throughput: 2835 kg/h PE film content: 3.7% 8 -ve on minimized stream 7 feed 10 NIR A Mixer 1 -ve Fibre 12 +ve All Plastic Film 11Throughput: 900 kg/h PE film content: 21.2% NIR D Paper/Fibre (JRM) Throughput: 2568 kg/h PE film content: 0.3% NIR D Sorting Instructions Test 1: +ve PE and PP films Test 2: +ve PE films Plastic Film Flow Key Throughput: 1509 kg/h PE film content: 18.2% +ve on maximized stream 7 feed 9 -ve on contaminants 15 Throughput: kg/h PE film content: 89.1% Film Recovery Flow 3D Material Other Unwanted Product Ejected Fraction Contamination Throughput: 2548 kg/h PE film content: 4% Throughput: 1002 kg/h PE film content: 2.9% Processing trials for household film waste 35

36 Table 13 Quality, Reject and purity for NIR A and D in Test 1 NIR A Error NIR D Error Quality (Q) 95.7% ± 1.3% 84.9% ± 1.9% Reject (R) 78.4% ± 1.0% 98.0% ± 1.4% Total film content in product 22.2% ± 1.3% 90.4% ± 2.2% PE Purity 21.2% ± 1.3% 89.1% ± 2.2% This preliminary trial demonstrated that NIR A was recovering 95.7% of film fed to it (as a minimum 94.4% when the error is accounted for) and NIR D was creating a high purity PE film product, with a purity of 89.1% (minimum of 86.9%) while still recovering 84.9% (minimum of 83.0%) of the film fed into it. NIR C was programmed to eject all material to minimise the throughput of the drop fraction going to Mixer 1 (Figure 9), since in theory this should have only been 3D material. Due to the set-up of the plant all the material was ejected to prevent it from entering NIR D. Approximately 90% of material fed into NIR C was ejected; however, due to the inefficiency of the disc screen further upstream in the process a large amount of film was lost in this stream. It is important to note this plastic film loss, as it indicates that less film was available for recovery by NIR D. The preliminary test successfully demonstrated the NIR sorters were performing as expected (despite the losses experienced), and as a result, successive trials were conducted with no change to the NIR operating parameters Mass balance analysis around Mixer 1 In Section 4.4.3, the measurement of instantaneous throughput of NIR A ejects in stream 11 ( Figure 21) was taken due to restrictions in access. During Test 1, the instantaneous throughput measured ranged from 600 to 1,050 kg/h. This range indicated that material flow in stream 11 was not at steady state (constant). A representative mass flow for the NIR A ejects was required to calculate the efficiency of the NIR sorter. Taking an average of the range on measured throughputs would not be representative of the exact process operation due to: the human error brought about by starting and stopping the stopwatch; the limited period of time over which the measurements were taken; and the significant variability in composition between each sample. Throughout the collection of these samples, it was observed that the material coming into Mixer 1 was approximately split between 75% from stream 11 and 25% from stream 10 (Figure 21). The low flow rate of stream 10 was expected as NIR C was set to eject all feed material it processed to a product bay rather than allowing it into the mixer. Processing trials for household film waste 36

37 Figure 21 Snapshot of Mixer 1 material flow Upon compositional analysis of the collected samples from NIR A eject, the values of Q and R were calculated for a range of different throughputs from the NIR A rejects as shown in Table 14. A comparison of the separation efficiencies at different throughputs was fundamental in establishing a mass balance around Mixer 1. Table 14 Mass balance variation around Mixer 1 NIR A performance Throughput (kg/h) Quality Error Reject Error % ± 1.3% 84.5% ± 1.1% % ± 1.3% 81.3% ± 1.0% % ± 1.3% 78.4% ± 1.0% 1, % ± 1.0% 75.7% ± 1.0% Notably from Figure 22, the variation in the Q values were not significantly affected by the change in throughput, with an increase of only 3.0% observed as the throughput is increased from 600 to 1,050 kg/h. Similarly, despite nearly doubling the throughput, the reject rate decreased by a minimal amount of 8.8%. In both cases, the error in the result (Table 14) is also fairly constant throughout the different throughputs. From this analysis, it is clear that an increase in throughput of this magnitude does not significantly affect the performance of NIR A. Processing trials for household film waste 37

38 Separation Efficiency (Q and R) Figure 22 Comparison of NIR A performance with increasing throughput 100.0% Quality - Q Reject - R 95.0% 90.0% 85.0% 80.0% 75.0% 70.0% Throughput (kg/h) The feed rate of NIR D (stream 13, refer to Figure 9) was calculated to be 1,187 kg/h by using the flow rates of the eject and reject streams from NIR D which were measured. Since it has been shown that fluctuations in the throughput have little effect on the efficiency of the NIR it was decided that the 3:1 split of throughput between NIR A ejects and NIR C rejects would be used to calculate the throughput of the NIR A ejects. This was calculated as 900 kg/h. This throughput was used as the mass balance in all subsequent calculations. 5.2 Test 2: Generation of PE film for Régéfilms The primary aim of this test was to produce a high purity PE film product which could then be reprocessed by Régéfilms to produce pellets for film extrusion. As the setting for this test were the same as for Test 1, it was not necessary to conduct further compositional analysis on any of the product streams. Instead, a mass balance over the whole plant was performed; the results of the mass balance are provided in Table 15. Processing trials for household film waste 38

39 Table 15 Mass balance of whole plant for Test 2 Total mass of each stream (kg) % of feed reporting to each stream Material fed into plant 105, % Handpicked cardboard 1, % Ferrous 1, % Fines 23, % NIR A reject (non-film) 25, % NIR C reject (3D non-film) 33, % NIR D reject (non-film) 17, % NIR D eject film product 2, % It can be seen that 2,040 kg of film product was produced during the test. Only 1.9% of the total feed material processed was recovered as product in this trial. This is low considering the feed contained 7.4% film, and the recovery would be expected to be closer to this value. One reason for the lower yield of film product was the inefficiency of the disc screen, as discussed in the Section 5.1. The waste 3D fraction and fines fraction from the disc screen contained a significant amount of film which should have been sorted into the 2D fraction, and so was lost as waste and could not be recovered in the product stream. It can be assumed that the composition of the various fractions obtained from this trial is the same as that measured in Test 3, as identical operating conditions were used. 5.3 Test 3: Assessment of PE film separation A full mass balance and compositional analysis was carried out during Test 3. Full details of the assessments can be found in the Table 29, Appendix 4 and Table 32, Appendix 5 respectively. Key results and findings of the test are discussed in this section. In this test the Quality (Q) and Reject (R) were calculated for NIR A and D to assess their performance. NIR D was set to eject only PE film; the same settings were used as in Test 2. Table 16 shows the mass flows and composition of each stream entering and exiting the NIR sorters. Processing trials for household film waste 39

40 Composition Table 16 Mass balance on NIR A and D for Test 3 Throughput (kg/h) NIR A Composition Throughput (kg/h) NIR D Composition Target PE film in feed % % Other materials in feed 3, % % Total in feed 4, % 1, % Target PE in film eject % % Other materials in eject % % Total in ejects % % Target PE film in reject 9 0.3% % Other materials in reject 3, % % Total in reject 3, % % Figure 23 provides a graphical illustration of the composition of each product stream assessed during Test 3. It should be noted that there is a low concentration of PP film in the NIR D ejects (which is the PE product stream). The presence of PP film could be as a result of: Incorrect identification by NIR D; or Presentation of feed material to NIR D, i.e. a piece of PE film on top of a piece of PP film resulting in both pieces of film being ejected by the NIR. Figure 23 Composition of NIR feed and product streams during Test 3 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% Other material PP film PE film 0% NIR A Feed NIR A Ejects NIR A Rejects NIR D Feed NIR D Ejects NIR D Rejects Processing trials for household film waste 40

41 Table 17 Q and R of NIR A and D for Test 3 NIR A Error NIR D Error Quality (Q) 95.9% ± 1.4% 78.7% ± 3.1% Reject (R) 82.6% ± 2.8% 97.7 % ± 1.7% Total film content in product 24.7% ± 1.4% 92.3% ± 3.9% PE Purity 23.6% ± 1.4% 91.5% ± 3.9% The Q, R and purity of PE film in the eject fraction for both NIR sorters are provided in Table 17. The data collected shows that the NIR A was able to eject the majority of the film fed into it (approximately 95.9%) while allowing for 82.6% of the non-target material to be separated into the reject stream. NIR A was able to increase the purity of the film from 5.3% in the feed to 23.6% in the eject stream. This is far from pure, however it must be noted that the purpose of NIR A is to eject all plastic film not just PE, and since the ejects are to be processed again using a second NIR (NIR D) it is more advantageous to recover the majority of the PE film at this stage rather than increasing its purity. NIR D had a lower Q than NIR A, meaning less PE film was ejected and more allowed to pass through to the reject stream (21.3% of PE film fed into NIR D was lost). However, the purpose of NIR D was to increase the purity of the film product, and with an R of 97.7% (97.7% of the nontarget material fed into the NIR was separated into the reject stream) and an increase in the film purity from 23.6% to 91.5%, it demonstrates it has achieved this effectively. 5.4 Test 4: Assessment of PE and PP film separation Once again a full mass balance and compositional analysis was carried out. Full results are shown in Table 30, Appendix 4 and Table 33, Appendix 5 respectively. Analysis of the performance of NIRs A and D are discussed in this section. Test 4 was conducted to determine the maximum likely contamination of the PE film if PP film was also recovered, and the resulting effect on the PE separation efficiency. To do this NIR D was programmed to eject both PE and PP film. The mass flows and composition of each stream are provided in Table 18. Processing trials for household film waste 41

42 Composition Table 18 Mass balance on NIR A and D for Test 4 NIR A Throughput Composition (kg/h) NIR D Throughput Composition (kg/h) Target PE film in feed % % Target PP film in feed % % Other materials in feed 4, % 1, % Total in feed 4, % 1, % Target PE film in eject % % Target PP film in eject % % Other materials in eject % % Total in ejects % % Target PE film in reject 8 0.2% % Target PP film in reject % 2 0.2% Other materials in reject 3, % 1, % Total in reject 3, % 1, % Figure 24 shows the compositions from Test 4. It can be seen that there is clearly more PP film in the NIR ejects than in Test 3 when PP was not ejected. Figure 24 Composition of the NIRs feed and product streams in Test 4 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% Other material PP film PE film 0% NIR A Feed NIR A Ejects NIR A Rejects NIR D Feed NIR D Ejects NIR D Rejects Processing trials for household film waste 42

43 The Q and R for both NIR sorters are given in Table 19. Three Q values were calculated for this test; one considering PE only as the target stream, one considering PP only as the target stream and one considering both PE and PP as the target steam. Table 19 Q and R of NIR A and D for Test 4 NIR A Error NIR D Error Quality (Q) PE only 96.5% ± 1.2% 76.5% ± 1.7% Quality (Q) PP only 94.0% ± 0.3% 83.5% ± 0.8% Quality (Q) PE and PP 96.3% ± 1.2% 76.8% ± 1.9% Total film content in product 27.0% ± 1.2% 89.7% ± 1.8% Reject (R) 84.1% ± 1.2% 97.8% ± 1.8% PP and PE Purity 25.2% ± 1.1% 84.2% ± 2.2% Test 4 yielded similar results to Test 3. A comparison between the two trials will be given in the following section. Interestingly, the Q value for PP is higher than that for the PE for NIR D. This could be because the throughput is far less for PP (12.5 kg/h rather than 230 kg/h for the PE), allowing it to be sorted more effectively. 5.5 Comparison of results from Test 3 and Test Assessment of NIR A performance Tests 3 and 4 provided detailed information about the performance of NIR A in recovering all plastic film from the 2D feed material. Comparing the results of the two tests provides an indication of the variation in Q, R and purity values recorded during the like-for-like tests and an indicative assessment of the accuracy of the results. As NIR A had the same settings for both Test 3 and Test 4, it is anticipated that the Q, R and purity values should be similar. Table 20 compares the performance of NIR A on both tests. Figure 25 provides a graphical representation of the data. Table 20 Performance of NIR A in Test 3 and Test 4 NIR A Test 3 Error NIR A Test 4 Error Quality (Q) (PE only) 95.9% ± 1.4% 96.5% ± 1.2% Reject (R) 82.6% ± 2.8% 84.1% ± 1.2% PE Purity 23.6% ± 1.4% 25.5% ± 1.1% Processing trials for household film waste 43

44 Figure 25 Performance of NIR A in Test 3 and Test 4 It can be seen that the performance of NIR A does not change significantly between the two tests. The Q and R values calculated are slightly higher in Test 4, as is the purity; however, slight fluctuations in Q and R would be expected, as feed quality may change throughout the tests. Furthermore, since the values for Test 4 lie within the same error limits as Test 3 (as shown in Figure 25), it may be that the sampling methodology used could be a reason for the slightly different values Assessment of NIR D performance Tests 3 and 4 provided detailed information about the performance of NIR D in recovering PE film only, and PE and PP film as a combined target stream. Comparing the results of the two tests provides an indication of the variation in Q, R and purity values for each of these different settings. Table 21 shows a comparison of the performance of NIR D in both trials and Figure 26 is a graph of the data. Table 21 Performance of NIR D in Test 3 and Test 4 NIR D Test 3 Error NIR D Test 4 Error Quality (Q) (PE only) 78.7% ± 3.1% 76.5% ± 1.7% Reject (R) 97.7% ± 1.7% 97.8% ± 1.8% PE Purity 91.5% ± 3.9% 84.2% ± 2.2% Processing trials for household film waste 44

45 Figure 26 Performance of NIR D in Test 3 and Test 4 As expected, since PP film is also ejected in Test 4, the PE purity achieved by NIR D was lower than in Test 3, reducing by 7.4% when PP was also ejected. In Test 4, 4.8% of the film product was PP, whereas when only PE was targeted (in Test 3) 0.5% of the product was PP Commentary on NIR A and NIR D performance It may be expected that the recovery efficiency of PE would increase if PP is also fired on based on the fact that in NIR A when all film is ejected, the Q value is very high. However this was not what was observed in the trials. The Q value for PE was lower in Test 4, meaning that less of the available film was recovered. However, it was only 2.2% lower and this may be attributed to fluctuations in the feed quality; this fall is within the errors of the test data. Overall, the NIRs were able to perform the desired separations efficiently, creating a high purity film product and recovering a large proportion of the film fed into the sorters. Processing trials for household film waste 45

46 6.0 Generation of PE pellet 6.1 Methodology This section of the report considers the reprocessing of the PE film generated in the first two stages of the project. This stage of the project aimed to determine if the sorted PE film produced by the NIR separators could be successfully reprocessed by a film recycling plant into PE pellets suitable for resale and downstream product manufacturing. It was proposed that the film fraction separated by the Pellenc NIR equipment would be processed at the Régéfilms facility in Abidos, South France. The Régéfilms facility currently produces recycled PE pellets from a mixture of European sourced household film and agricultural film. Régéfilms typically find that the agricultural film it sources has lower levels of contamination than household film sources and a higher bulk density, making it easier for them to process. In normal operation both film types are reprocessed together through the plant producing a high quality pellet. The facility utilises a range of separation techniques in order to clean the PE film to a level at which it can be extruded into a high quality pellet at a reasonable throughput rate. Figure 27 shows a flow diagram of the process employed by Régéfilms. The washing phase is used to remove any dirt and oil/fat contamination that may be on the surface of the film. Removing these contaminants reduces the generation of gas through the extrusion process and also minimises the extruder filtration requirements, resulting in higher quality pellet production. Figure 27 Flow diagram of Régéfilms process Feed Feed Preparation NIR A NIR B waste Metal and all other contaminants Remaining contaminants excluding metal PE pellet product Washing and Extruding Process waste 6.2 Results It was demonstrated that PE pellets could be successfully produced from the UK sourced household film at the Régéfilms facility, as shown in Figure 28. A total of 2.67 t of baled household PE film from BS Environnement MRF was processed at a rate of 0.88 t/h to generate a clean film fraction. From this, 1.79 t of PE pellet was produced at a rate of 0.52 t/h. Processing trials for household film waste 46

47 Figure 28 PE pellet produced from UK household film During the trial, a mass balance was undertaken to determine the yield and losses during reprocessing. Data from the mass balance assessment can be viewed in Table 22. The scales used had an error of ±1 kg and a mass of 1.5 kg was subtracted when material was weighed in a bulk bag in order to account for the tare weight of the bag. The overall yield for the trial was calculated to be 66.6%. Table 22 Mass balance for Régéfilms trial Stream Inputs Outputs PE film feed material generated at BS Environnement MRF NIR A ejects (metal and other contaminants) Weight of stream (kg) % of feed 2, % NIR B ejects (other contaminants) % Feed preparation, washing and extrusion waste, loss of moisture and losses from start/stopping of line % Product (PE pellet) 1, % It should be noted that the 66.6% yield is based on the total mass of the feed. Typically Régéfilms find that the film infeed contains 10% moisture by weight. Furthermore since less than 3 tonnes of film was processed, the losses from starting and stopping the line are significant compared with the plant usual 24 hour production. Processing trials for household film waste 47

48 Régéfilms conducted its standard laboratory testing on the PE product, which included measuring the moisture, Melt Flow Index (MFI) and density. Table 23 shows the results of the testing along with the specifications for standard product. Two bags of product were made and representative samples were taken from both and analysed. Table 23 Physical properties of PE pellets Moisture (ppm) MFI (g/10 minutes) Density (kg/l) Bag Bag Normal Régéfilms specification < <MFI< <Density<0.94 The analysis shows that the PE pellet produced from the film met the Régéfilms specification for all three laboratory tests. This is a further indication that the pellet produced will be suitable for use in the manufacture of refuse sacks. In addition to the above, Régéfilms staff commented on the low level of contamination in the separated and cleaned film prior to extrusion and were overall satisfied with the way in which the film was reprocessed and the fact there were no major operating issues. 6.3 Conclusions The following conclusions can be drawn from the reprocessing trial at Régéfilms: the NIR separators were able to remove unwanted material of the UK sourced household plastic film to a level at which it was possible to successfully produce PE pellets; no major obstacles were encountered during processing and the film handled in a comparable manner to Régéfilms standard post-consumer film infeed, although at a lower throughput rate; the lower throughput rate was likely due to the absence of agricultural film, which is normally used by Régéfilms to increase the bulk density and reduce overall contamination levels; and laboratory analysis showed that the PE pellet met Régéfilms product specification for moisture, MFI and density and the lack of surface defects indicated low gas content. Processing trials for household film waste 48

49 7.0 Manufacture of end-product This section of the report details the manufacturing trial undertaken by CeDo at its UK facility in Telford. CeDo is a European leader in the manufacture and supply of consumer film products. Its product range includes refuse sacks, bin liners and cling film. CeDo operates a film recycling facility in the Netherlands, which processes primarily agricultural film. The PE pellet produced from this recycling operation is currently used in the manufacture of refuse sacks. The objective of this phase of the project was to determine if the PE pellets produced by Régéfilms were of a sufficiently high quality to be used for end markets applications. Refuse sacks were chosen to be produced to allow a direct comparison with the refuse sacks produced by CeDo. CeDo s standard post-consumer recyclate (PCR) is sourced predominantly from agricultural film in Europe as well as kerbside collections in Germany, and does not contain any UK kerbside collected film. Throughout this section, trial PCR will refer to the PE pellets produced at Régéfilms from the UK sourced household film. CeDo PCR will refer to the PCR produced by CeDo in the Netherlands, primarily from agricultural film and currently used in the manufacture of its products. 7.1 Process description Refuse sack products are manufactured from specific quantities of recycled PE polymer, chalk and small quantities of virgin Medium Density Polyethylene (MDPE), referred to as the recipe. The chalk is a bulking agent and the virgin MDPE improves the physical properties of the refuse sacks. The quantity of each material used is dependent upon the end product specification and the physical properties required. The typical recipe used by CeDo to produce saleable refuse sacks contains 40% PCR, and the breakdown of the other components is shown in Figure 29. Figure 29 Recipe used for comparison of PCR In-House Recyclate, 23% Virgin MDPE, 7% Post- Consumer Recyclate, 40% Chalk, 30% The CeDo manufacturing facility is equipped with a large range of film blowing lines in order to produce the range of products it supplies. Film blowing is the process of extruding a polymer through a ring-shaped die into a bubble. The bubble is then collapsed into a sheet of film and rolled up. A schematic of a film blowing line is given in Figure 30. Figure 31 shows a film bubble during the processing trial at CeDo. Processing trials for household film waste 49

50 Figure 30 Schematic of film blowing line Figure 31 Blowing of PE film during CeDo trial 7.2 Methodology The initial test aimed to compare the properties and quality of the trial PCR with CeDo s standard PCR using a well-established recipe. Subsequent tests were then conducted to determine how the Processing trials for household film waste 50

51 quality of the film produced from the trial PCR varied according to the proportion of PCR used in the recipe and the thickness of the film bags produced. To increase the PCR content more PCR was added and the amount of in-house recyclate was reduced. The levels of virgin MDPE and chalk were kept constant throughout all samples. The thickness of the film bags produced can be reduced by increasing the speed of the rollers, which pull the film through the collapsing frame without altering the overall throughput. The following samples shown in Table 24 were manufactured and sampled during the trial. Table 24 PCR content and thickness of refuse sacks made using trial PCR PCR Content Thickness 40% 22 μm 40% 17 μm 50% 22 μm 63%, no desiccant 22 μm 63%, with desiccant 22 μm 63%, with desiccant 17 μm 7.3 Results and conclusions Refuse sacks were successfully manufactured by CeDo using household plastic film derived from UK. Figure 32 shows examples of different refuse sacks manufactured; (left to right) CeDo recipe ; trial recipe 40%, 22μm; trial recipe 50%, 22μm and trial recipe 63%, 17μm with desiccant. Figure 32 Rolls of refuse sacks made using various quantities of PCR Processing trials for household film waste 51

52 Refuse sacks were manufactured to the following specifications with no significant processing problems: 22 µm thick film containing 40% CeDo PCR. This was a control sample produced using normal specifications to compare the trial material to; 22 and 17 µm thick film containing 40% trial PCR; 22 µm thick film containing 50% trial PCR; 22 µm thick film containing 63% trial PCR; and 22 and 17 µm thick film containing 63% trial PCR and 1% desiccant. The trial PCR was shown to be of a high quality for the following reasons: all film was successfully blown with no bubble collapses, except for when processing 17 μm thick film. This is considered very thin and bubble collapse at this thickness are to be expected; all film produced using the trial PCR had very few gels (small black dots caused by polymer chains bonding) or visual contaminants, resulting in high quality aesthetics; lensing in the film caused by moisture only became an issue at high trial PCR contents of 63%; however, this was easily resolved by adding a desiccant. The addition of desiccants is a standard procedure in film manufacturing, dependent upon the feed material used; when tested, the resulting film had mechanical strength of a comparable standard to the film manufactured using standard CeDo PCR; and even at high trial PCR content, the film showed strong physical properties. The main concerns over the material produced during this stage were: the film produced using trial PCR had a distinct odour when compared to CeDo PCR, which could have impact in its saleability. If this end market application is to be pursued, the trial PCR could be blended with other material to reduce the odour; alternatively, a retailer and customer perception analysis could be considered to determine the saleability of the product; and the test conducted was of a small scale; the results obtained may not be representative of the likely quality on a wider scale. In conclusion, the test found that the trial PCR processed was of a high quality, with properties comparable to the standard PCR used by CeDo. This demonstrates that the NIR sorters analysed can successfully and effectively separate the household PE film from other recyclables, allowing for the production of the high quality film. Larger scale production trials may be required, identifying alternative end market applications, along with retailer and customer perception testing to examine the consistency of outputs and the likely impact of characteristics such as odour could have on the saleability of the final product. Processing trials for household film waste 52

53 8.0 Economic assessment In order to determine the commercial benefits of a MRF investing in and using NIR of the type tested, to produce a high purity film bale (containing greater than 90% pure PE film), an economic assessment was carried out to compare the technology against an alternative approach of hand picking a film stream from dry recyclables. The economic assessment compared the Net Present Value (NPV) of a MRF using hand picking against an equivalent MRF using NIR sorters to produce separated mixed paper and film product streams from the 2D fraction of co-mingled kerbside collected dry recyclables. The assessment is based on a typical MRF separating 150,000 tpa co-mingled kerbside collected recyclables at a rate of 25 tph (6,000 operational hours per year). It assumes that both the hand picking and NIR sorting options would use the same upstream 2D/3D separation process to remove 3D material and fines. As a result, the economic assessment considers only the separation of the 2D fraction into mixed paper and film product streams. It is acknowledged that additional NIRs or hand pickers would be required to clean up the paper fraction, and the value of this stream has been taken to be below average to account for the reduced quality output. Simplified process flows were used for each option (hand picking and NIR sorting). Figure 33 gives the mass balance for the 2D/3D separation and screening. Values are based on information gathered during the trials at Casepak and BS Environnement and assumptions based on Axion s experience. Figure 33 2D/3D separation mass balance for both options Figure 34 shows the mass balance for the hand picking option. The calculations were based on the 2012 WRAP report, Film reprocessing technologies and collection schemes 8. The model uses 16 hand pickers per shift, working at a rate of 0.04 t film/h. Processing trials for household film waste 53

54 Figure 34 Mass balance for hand picking of film from 2D fraction Figure 35 shows the mass balance for the NIR sorting option. The data obtained from the BS Environnement NIR efficiency trial was used in the calculations. Figure 35 Mass balance for NIR sorting of film from 2D fraction In order to perform the economic analysis, the values given in Table 25 have been used. These values have been taken from published data, liaison with MRF operators and from Axion s experience in the waste and recycling sector. Table 25 Product/feed values used for economic assessment >90% pure PE film bale 75 8 Grade C film ( 80% PE film) 5 Un-separated 2D stream (6% film) Mixed paper stream (<1% film) WRAP (2012), Film reprocessing technologies and collection schemes, 9 WRAP (2012). Gate Fees Report 2012, 10 LESTSRECYCLE.COM (2013), Waste paper prices, Note: Lower value for mixed paper applied due to contamination in product output. Processing trials for household film waste 54

55 Grade C film is a product typically produced by MRFs and has an estimated composition of 85% PE film. This value was chosen after discussions with MRF operators giving a specification of the grade C film product. The remainder of the material contains paper, non-pe film, rigids and metal contaminants. Table 26 shows the operating and capital costs for each option, along with the annual revenue from the mixed paper stream and film product stream. The operating cost for the hand picking line is based on a cost of 10/h for labour with an additional 20,000/year for costs such as heating and electricity for the picking shed. An installation cost of 375,000 has been used for each NIR sorter, with a 10/h operating cost. The additional revenue can be calculated by adding the sales from the paper and film streams to the savings gained by not selling the un-sorted 2D fraction for 20/t. Table 26 Annual costs and revenues for each film sorting option Hand picking NIR sorting Capital cost 75, ,000 Operating cost 980, ,000 Additional annual revenue through sales of paper and film 3,860,000 4,170,000 Net revenue 2,880,000 4,050,000 The table above shows that producing a high grade film output leads to higher revenues (an additional 310,000 per year), furthermore the operating cost is significantly lower for NIR sorting compared to hand picking, leading to greater net revenue for this option. This means that even if the high grade film was sold at Grade C film prices as calculated in this model, NIR sorting would still remain the preferable option. If the price of high purity film is equal to Grade C bales, NIR sorting gives a net income 1.17 million per annum more than hand sorting. Table 27 gives the NPV for each option after five and ten years. It shows once again that using NIR sorting is significantly more profitable than hand picking film. Table 27 NPV for each option Hand picking NIR sorting NPV after 5 years 10,850,000 14,620,000 NPV after 10 years 17,630,000 24,160,000 The analysis suggests that using NIR sorters may be more beneficial than hand sorting, attributable primarily to the significantly reduced operating cost of the NIR sorters. This indicative analysis is useful for MRF operators who are currently using hand picking and are seeking to replace this operation with NIR sorters. This assessment can also be used to inform the initial design stage of a new build MRF when considering the feasibility of hand picking and NIR sorting for film streams. 11 WRAP (2012), Film reprocessing technologies and collection schemes, Processing trials for household film waste 55

56 In order to ensure that an accurate estimate of the economic viability of using NIRs is conducted for a specific site, it is recommended that a bespoke assessment is conducted prior to any investment decisions being made; this assessment should take into account any site specific issues, such as composition of infeed material, and material price data trends. It should also be advised that this assessment has been conducted on the assumption that suitable buyers for all of the material produced can be secured. Processing trials for household film waste 56

57 9.0 Overall conclusions 9.1 NIR sorting The tests conducted at the BS Environnement MRF in France demonstrated that the NIR sorters tested were able to either effectively recover the majority of PE film (over 95%) fed into them at a low purity giving a high yield, or produce a high purity PE film (91%) product whilst minimising losses at a lower yield. It was also shown that the NIRs can effectively recover PP if programed to do so. 9.2 Reprocessing stage using film separated by the NIRs The film output generated during the sorting trials at the BS Environnement MRF was transported to Régéfilms reprocessing facility in Abidos, South France. A reprocessing test was conducted to determine whether quality PE pellets could be generated from the film. It was demonstrated that: the NIR separators at BS Environnement MRF were able to remove unwanted material of the UK sourced household film to a level at which it was possible to successfully produce PE pellets using the Régéfilms process; no major obstacles were encountered during processing and the film handled in a comparable manner to Régéfilms standard film infeed (i.e. agricultural and household), although at a lower throughput rate; the lower throughput rate was likely due to the absence of agricultural film, which is normally used by Régéfilms to increase the bulk density and reduce overall contamination levels; and laboratory analysis showed that the PE pellet met Régéfilms product specification for moisture, MFI and density and the lack of surface defects indicated low gas content. The PE pellet was considered to be of good quality and suitable for end products application. Manufacturing test at CeDo found that the pellets from the trial processed at a high quality, with properties comparable to the standard pellet used by CeDo. This demonstrates that the NIR sorters tested successfully and effectively separated the household PE film from other recyclables, allowing for the production of the high quality film. As the test was conducted at a small scale, large scale production tests may be required to analyse differences in the quality of the feedstock from a wider source. Depending on the end market, retailer and customer perception tests to examine the consistency of outputs and the likely impact of characteristics like odour could have on the saleability of the final product. 9.3 Economic assessment: Use of Pellenc NIR to replace hand sorting operations An economic assessment suggests that using NIR sorters like the one tested in UK MRFs processing kerbside co-mingled recyclables may be more beneficial than hand sorting; this is attributable primarily to the significantly reduced operating cost of the NIR sorters. This indicative analysis is useful for MRF operators who are currently using hand picking and are seeking to replace this operation with NIR sorters. This assessment can also be used to inform the initial design stage of a new build MRF when considering the feasibility of hand picking and NIR sorting for film streams. In order to ensure that an accurate estimate of the economic viability of using NIRs is conducted for a specific site, it is recommended that a bespoke assessment is conducted prior to any investment decisions being made; this assessment should take into account any site specific issues, such as composition of infeed material, and material price data trends. It should also be advised Processing trials for household film waste 57

58 that this assessment has been conducted on the assumption that suitable buyers for all of the material produced can be secured. Processing trials for household film waste 58

59 Appendix 1 Additional information about the sorting technology assessed Introduction The technology assessed during this project was a Pellenc Mistral NIR with a Turbosorter. NIR sorting technology works by illuminating objects on a conveyor belt and detecting the wavelength of reflected light. Depending on the type of material, different wavelengths of light are reflected and a special sensor above the belt can determine the material type from this fingerprint of wavelengths. The equipment then instructs a row of air jets further down the conveyor belt to fire out any material that it has been programmed to search for. The material blown away by the air jets is referred to as the eject fraction, whereas the material that is unaffected is called the reject/drops fraction. The machine can be programmed to eject the target material (the desirable fraction) or the non-target fraction (the undesirable fraction). NIR technologies are well established in UK MRF operation and can be supplied by a range of different companies. The TurboSorter The unique aspect of the NIR assessed is that it is designed to retain the position of the film on the conveyor belt. As film is so lightweight, it can easily be blown about and change position on the conveyor once it has been detected. If this happens the air jets may not target the correct material, resulting in not all of the detected film being ejected. This can mean that the film contaminates the desirable/target fractions. This issue was addressed by covering the conveyor as it enters the NIR and generating an air flow which moves at the same speed as the conveyor. This effectively pins the feed material to the conveyor, preventing lightweight items from rolling or being blown about. The objective of this airflow is to improve the accuracy of the NIR sorter and improve separation efficiencies where lightweight items, such as plastic films, are found in the feed material. This system is known as a Turbosorter. The TurboSorter provides a totally enclosed system that stabilises the light-weight articles, which are projected within the air flow along a known and predictable trajectory. Processing trials for household film waste 59

60 The illumination system Pellenc has developed a new illumination system to aid the NIR sorting process, which aims to optimise the concentration of light on each object to be sorted, as shown below. Reflector Lamp Object The detection system Pellenc NIR technology uses high speed, high quality scanning mirrors. Light reflected from objects is gathered from the detection spot within a few microseconds. The light is carried via an optical fibre bundle from the gathering optics to a dedicated spectrometer, which is safely located in the temperature controlled electrical cabinet of the machine. This spectrometer restricts acquisition to a few dedicated wavelengths, optimised for the most appropriate portions of the NIR spectrum. The optical scanning with focused illumination line is shown on the left below and the dedicated spectrometer shown on the right below. Processing trials for household film waste 60

61 Description of Pellenc NIR technologies used in the trials at BS Environnement and Régéfilms Name of facility Name of machine Type of machine TurboSorter Patented lighting system Patented NIR detection and settings Metal Detection: Nozzle operated induction sensors to remove metal Blowing techniques and output boxes BS Environnement NIR A Mistral with NIR spectrometer Yes Yes Separation of plastics from fibre No Dedicated NIR D Mistral with dedicated spectrometer: SPIN/Films Yes Yes Separation of PE Films from other plastics No Dedicated Processing trials for household film waste 61

62 Appendix 2 Details of Local Authority kerbside collection schemes used in the trial Walsall Metropolitan District Council Walsall Metropolitan District Council (WMDC) currently provides the following kerbside waste collection services: weekly kerbside co-mingled recycling collection, green wheeled bins; weekly garden waste collection, brown bin; and weekly residual waste collection, grey wheeled bins. Further details regarding materials specified for kerbside co-mingled recycling collections are provided below 12. Requested items Plastic bottles, tubs and trays: Plastic bottles (milk, pop, water, cleaning products, beauty products), margarine tubs, butter tubs, soft cheese tubs, egg boxes, yoghurt pots, cream pots, white ready meal food trays, clear fruit trays; Paper and card: Newspapers and magazines, junk mail, greeting cards, envelopes, wrapping paper, yellow pages, telephone directories, paperback books, writing paper, printer paper, shredded paper, cardboard and corrugated boxes, cereal boxes, washing powder boxes, milk or fruit juice cartons, egg boxes; Food and drink cans: Food cans, drink cans, aerosol cans (no lighter fuel cans); Glass: Glass bottles (all colours), jars (no tops); Carrier bags: Empty carrier bags only (no other types of plastic bag, no black bin liners, no bagged waste); and Other: Tin foil, foil dishes. Excluded items Black bin liners; Bagged waste; Food wrappers; Bubble wrap; Shiny plastic wrappers for example crisp packets, sweet wrappers, tea bag packets; Pet food pouches; Toys; Electrical goods; Tupperware; Polystyrene; Black food trays; Hardback books; Pyrex or cooking dishes; Window glass; Picture glass; Drinking glasses; Mirrors; Food waste; Nappies; Clothes; Garden waste; and Batteries. 12 WMDC (2012), Recycling collection, Processing trials for household film waste 62

63 South Holland District Council South Holland District Council (SHDC) currently provides the following kerbside waste collection services: weekly kerbside co-mingled recycling collection, materials may be presented in SHDC green sacks, carrier bags, cardboard boxes or a suitable rigid container for collection; and weekly residual waste collection, grey wheeled bins. Further details regarding materials specified for kerbside co-mingled recycling collections are provided below 13. Requested items Paper and cardboard; All plastic bottles; Plastic carrier bags; Yoghurt pots; Margarine tubs; Ice cream tubs; Plastic film (type not specified); Food/drinks cans; Aerosols; Glass bottles and jars; Clean tin foil; Waxy cartons; Catalogues; and Clothing and shoes. Excluded items Broken glass; Electrical items; Toys; Wood; Liquids; Polystyrene; Nappies; Sanitary products; Pet bedding; Garden waste; Food waste; Clinical waste; and Commercial waste. 13 SHDC (2012), Green bag for recycling, D79AE3E1F351/0/Greensackprint.pdf Processing trials for household film waste 63

64 Appendix 3 Error propagation For all the composition analysis that was undertaken, the errors were calculated using Axion s inhouse sample calculator, discussed in Section To convey these errors for the Quality (Q), Reject (R) and Purity, the rules of error propagation were applied. Determining the errors in final performance analysis values enabled a confident judgement of the performance of the NIR s tested at the BS Environnement trial to be reached. The rules of error propagation 14 applied to all the samples analysed are as follows: 1. Addition or subtraction When calculating the Purity of a particular item in a stream for example PE film. A summation of all the PE fractions (HDPE, LDPE, LLDPE, etc.) was required. Consequently if the composition of the different PE films are a, b, c. and the errors (uncertainty) are, the Purity is calculated as follows: Then for the errors: 2. Multiplication or division When calculating the quality or reject for the same components a,b,c, Q is calculated as follows: Then for the error uncertainty: These two rules were applied to all the composition analysis that was carried out during the trials. They were also applied to all the calculated compositions in the mass balances. The errors were conveyed in the final quality, reject and purity results for each NIR whose performance was analysed improving the confidence in the results. 14 Harvard University, Rules for Error Propagation, Processing trials for household film waste 64

65 Appendix 4 Process Flow Diagrams Figure 36 Casepak MRF block flow diagram and mass balance UK Co-Mingled MSW (South Holland and Walsall Council) S-1 Casepak MRF S-3 2-D Material (to BSE France) S-2 3-D Material (incl losses) Composition Analysis Film Recovery 58.0% Data Collected at Casepak Stream no. S-1 S-2 S-3 Feeds from UK Co-Mingled MSW Casepak Casepak Feeds to Casepak 3-D Material BS Environment Material description Infeed 3-D Product 2-D Product Film Total Tonnage (tonnes) Non Film Total Composition (w/w %) Film 5.34% 4.24% 6.59% Non Film 94.66% 95.76% 93.41% Total % 100.0% % Processing trials for household film waste 65

66 Figure 37 Normal operating flow at BS Environnement MRF Ferrous 4 10 Fines 7 Feed 1 Hand Pick (5 People) 3 Overband Magnet 1 5 Star Separator NIR A NIR B Mixer Hand Pick (3 people) 15 Fibre (Paper, Magazine and Envelope) 2 Large Objects ve Plastic Film (except PP film) 13 +ve Cartons NIR C +ve Fibre 16 Mixer 2 18 Large Paper and Cardboard Key; Normal Mode Machine in conveyor mode Feed Material Product Stream Landfill Large Flats No PP film recycled Rigid Plastic & Film ELA Metal Residue Mixer 3 Hand Pick (1 person) Contamination NIR D 23 Rigid Plastic, ELA Metal, Residue 22 Plastic Film Contamination 24 Kinesorter E Paper and Cardboard (fines) Clear PET HDPE Hand Pick (1 Person) Hand Pick (1 Person) 37 Contamination ve (up) Dark PET Dark PET 31 +ve (down) Contamination NIR G (bi canal) +ve (up) ELA ve (down) Contamination ELA (Tetrapacks) Mixer 8 +ve (up) PET +ve (down) HDPE, ELA NIR F Rigid Plastic, ELA Metal, Residue +ve (up) HDPE, PET, ELA 26 Mixer 6 Mixer ve (down) Fibre NIR H (bi canal) +ve (down) Fibre 46 Paper and Cardboard (Large) Mixer 7 46 Overband Magnet 2 48 ECS Ferrous Non - Ferrous Waste Processing trials for household film waste 66

67 Appendix 5 Mass Balance Table 28 Mass balance for Test 1: Preliminary equipment assessment Trial Time 10 minutes Stream Description Weight (kg) % of feed reporting to each stream 1 In Feed % 2 Hand Pick % 4 Ferrous % 6 Disc Screen Fines % 9 NIR C Eject % 12 NIR A Reject % 14 NIR D Eject % 15 NIR D Reject % Table 29 Mass balance for Test 3: Assessment of PE film separation Trial Time 2 hours 10 minutes Stream Description Weight (kg) % of feed reporting to each stream 1 In Feed % 2 Hand Pick % 4 Ferrous % 6 Disc Screen Fines % 9 NIR C Eject % 12 NIR A Reject % 14 NIR D Eject % 15 NIR D Reject % Processing trials for household film waste 67

68 Table 30 Mass balance for Test 4: Assessment of PE and PP film separation Trial Time 2 hours Stream Description Weight (kg) % of feed reporting to each stream 1 In Feed % 2 Hand Pick % 4 Ferrous % 6 Disc Screen Fines % 9 NIR C Eject % 12 NIR A Reject % 14 NIR D Eject % 15 NIR D Reject % Processing trials for household film waste 68

69 Appendix 6 Composition Analysis Table 31 Composition analysis for Test 1: Preliminary equipment assessment NIR A Eject NIR A Reject NIR C Eject NIR D Eject NIR D Reject Component Composition Error Composition Error Composition Error Composition Error Composition Error LDPE Film 18.3% 0.9% 0.1% 0.1% 1.8% 0.3% 43.7% 1.5% 1.3% 0.2% HDPE Film 12.9% 0.9% 0.2% 0.1% 1.9% 0.3% 42.8% 1.5% 1.3% 0.2% LLDPE Film 1.3% 0.2% 0.0% 0.0% 0.0% 0.0% 2.2% 0.4% 0.0% 0.0% PP Film 1.9% 0.2% 0.0% 0.0% 0.6% 0.2% 0.7% 0.2% 0.4% 0.1% Metalized PE Film 0.7% 0.2% 0.0% 0.0% 0.2% 0.1% 0.4% 0.2% 0.4% 0.1% Other Film 1.1% 0.2% 0.0% 0.0% 0.4% 0.1% 0.6% 0.2% 0.6% 0.1% Black Film 0.0% 0.0% 0.0% 0.0% 0.1% 0.1% 0.0% 0.0% 0.1% 0.1% Fibre 55.8% 2.9% 99.0% 0.5% 88.7% 1.8% 5.9% 1.1% 88.0% 1.1% Composite cartons 2.0% 0.4% 0.0% 0.0% 1.0% 0.3% 0.3% 0.2% 0.9% 0.2% Other Recyclables 2.6% 0.6% 0.1% 0.1% 2.5% 0.5% 0.3% 0.2% 3.2% 0.3% Non-Recyclables 3.1% 0.5% 0.3% 0.1% 1.1% 0.3% 0.8% 0.3% 2.4% 0.3% Fines (< 50 mm) 0.3% 0.2% 0.2% 0.1% 1.7% 0.2% 2.2% 0.3% 1.4% 0.1% Processing trials for household film waste 69

70 Table 32 Composition analysis for Test 3: Assessment of PE film separation NIR A Eject NIR A Reject NIR C Eject NIR D Eject NIR D Reject Component Composition Error Composition Error Composition Error Composition Error Composition Error LDPE Film 14.4% 1.0% 0.1% 1.0% 1.1% 0.3% 49.0% 1.5% 2.7% 0.2% HDPE Film 20.2% 1.0% 0.1% 1.0% 2.0% 0.3% 41.4% 1.5% 2.6% 0.2% LLDPE Film 0.6% 0.1% 0.0% 0.1% 0.1% 0.1% 0.8% 0.4% 0.0% 0.0% PP Film 1.0% 0.3% 0.0% 0.3% 0.2% 0.1% 0.5% 0.2% 1.6% 0.1% Metalized PE Film 0.1% 0.1% 0.0% 0.1% 0.2% 0.1% 0.2% 0.2% 0.9% 0.1% Other Film 0.1% 0.1% 0.0% 0.1% 0.3% 0.1% 0.4% 0.2% 1.3% 0.1% Black Film 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% Fibre 56.8% 3.1% 99.2% 3.1% 89.4% 1.7% 3.2% 1.1% 78.3% 1.1% Composite cartons 2.1% 0.3% 0.1% 0.3% 1.5% 0.4% 0.2% 0.2% 0.9% 0.2% Other Recyclables 2.2% 0.6% 0.1% 0.6% 2.4% 0.5% 0.7% 0.2% 4.1% 0.3% Non-Recyclables 1.9% 0.6% 0.2% 0.6% 1.5% 0.4% 2.0% 0.3% 4.6% 0.3% Fines (< 50 mm) 0.6% 0.2% 0.1% 0.2% 1.4% 0.2% 1.5% 0.3% 2.7% 0.1% Processing trials for household film waste 70

71 Table 33 Composition analysis for Test 4: Assessment of PE and PP film separation NIR A Eject NIR A Reject NIR C Eject NIR D Eject NIR D Reject Component Composition Error Composition Error Composition Error Composition Error Composition Error LDPE Film 25.1% 0.9% 0.2% 0.1% 1.5% 0.3% 52.9% 1.6% 3.4% 0.3% HDPE Film 11.2% 0.7% 0.1% 0.1% 1.1% 0.3% 29.5% 1.5% 1.1% 0.2% LLDPE Film 0.3% 0.1% 0.0% 0.0% 0.0% 0.0% 1.0% 0.3% 0.1% 0.1% PP Film 1.7% 0.3% 0.0% 0.0% 0.3% 0.1% 5.0% 0.9% 0.2% 0.1% Metalized PE Film 0.3% 0.10% 0.0% 0.0% 0.6% 0.2% 0.6% 0.2% 0.3% 0.1% Other Film 0.4% 0.2% 0.0% 0.0% 0.2% 0.1% 0.7% 0.3% 0.5% 0.1% Black Film 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% Fibre 50.9% 3.4% 99.3% 0.6% 87.7% 1.9% 4.6% 1.4% 84.8% 1.5% Composite cartons 1.8% 0.3% 0.1% 0.1% 0.8% 0.3% 0.0% 0.0% 1.0% 0.2% Other Recyclables 3.4% 0.6% 0.1% 0.1% 3.5% 0.5% 0.4% 0.3% 3.7% 0.4% Non-Recyclables 4.7% 0.3% 0.0% 0.1% 1.6% 0.4% 3.7% 0.8% 2.9% 0.4% Fines (< 50 mm) 0.3% 0.1% 0.1% 0.1% 2.7% 0.3% 1.6% 0.3% 2.1% 0.2% Processing trials for household film waste 71

72