Table Of Content

Final report Environmental benefits of recycling – 2010 update An update to the 2006 WRAP report Environmental Benefits of Recycling, reviewing high quality Life Cycle Assessments from around the world to assess the impact of alternative waste management options for a range of materials, and discuss the findings for each material in the context of the UK. Project code: SAP097 Research date: March- December 2009 Date: March 2010 WRAP’s vision is a world without waste, where resources are used sustainably. We work with businesses and individuals to help them reap the benefits of reducing waste, developing sustainable products and using resources in an efficient way. Find out more at www.wrap.org.uk Written by: Jean-Charles Michaud, Laura Farrant and Olivier Jan from Bio Intelligence Service Birgitte Kjær and Ioannis Bakas, from the Copenhagen Resource Institute Front cover photography: WRAP, Bio Intelligence Service, and Copenhagen Resource Institute 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 steps have been taken to ensure accuracy, WRAP cannot accept responsibility or be held liable to any person 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 WRAP cannot guarantee the performance of individual products or materials. This material is copyrighted. It may be reproduced free of charge subject to the material being accurate and not used in a misleading context. The source of the material must be identified and the copyright status acknowledged. This material must not be used to endorse or used to suggest WRAP’s endorsement of a commercial product or service. For more detail, please refer to WRAP’s Terms & Conditions on its web site: www.wrap.org.uk Executive summary Context In 2006, WRAP (Waste & Resources Action Programme) published a major research report, Environmental Benefits of Recycling, based on an international review of life cycle analyses (LCA) that evaluated the impact on the environment of recycling, landfilling or incineration of key materials in UK waste streams. The review assessed 55 ‘state of the art’ LCAs on paper and cardboard, glass, plastics, aluminium, steel, wood and aggregates. The conclusion was clear – most studies show that recycling offers more environmental benefits and lower environmental impacts than the other waste management options. With the emergence of new waste management options and new waste streams in the last three years, WRAP has decided to update this report and ensure that policy makers and stakeholders are aware of the latest conclusions from LCA data on waste management options. The methodology behind the new report remains the same1 – careful screening of over 200 LCAs published worldwide since 2006 against strict criteria to focus on only the highest quality analyses. However, the scope of the review was changed in several ways:  New waste management technologies were added: composting and energy from waste (EfW) technologies such as anaerobic digestion, pyrolysis and gasification.  New waste streams/materials were added: food waste, garden waste, textiles and biopolymers.  Some materials were excluded from further analyses – aluminium, steel, glass and aggregates – as the results of the first study (that recycling is the preferred waste management option for these materials) are not impacted by the new technologies. In summary, the material / technology combinations of this study are shown in the following table (those included in the first report are highlighted in grey) Anaerobic  Recycling Composting Incineration  Landfill Pyrolysis Gasification digestion Paper and card x x x Plastics x x x x Biopolymers x x x x x Food and garden waste x x x x Wood  x x x Textiles x x x The key impact categories used for the assessment of the different waste management options were:  depletion of natural resources  climate change potential  cumulative energy demand  water consumption 1 The criteria used for the selection were: (i) the study had to be an LCA or LCA-like; (ii) includes a comparison of two or more end-of-life scenarios for the material fraction under study; (iii) representation of recycling or composting among the waste management options assessed; (iv) robustness of the publication, either peer reviewed or published in a scientific journal; (v) transparency in the assumptions made; (vi) primary research and not a review of previous work; (vii) no ambiguity in the way impacts are ascribed to materials; (viii) plausibility of the waste management options. Environmental benefits of recycling – 2010 update 1 Key conclusions from the LCA studies Because of the international nature of the study, the review has attempted to interpret the results in terms of UK impact. The key parameter in this respect in the energy mix used in the scope of a specific LCA, which might be quite different from that in the UK. The key conclusions are outlined below by material/waste type. Paper and cardboard  The results of the first study are confirmed in that landfilling of paper and cardboard is the least preferable option, particularly from a climate change potential and energy demand perspective.  The comparison between recycling and incineration appears more complex, as better energy recovery efficiencies have been built into the more recent LCAs. In general, the data shows that recycling is preferable for energy demand and water consumption, but they are comparable for climate change.  The key parameter affecting the comparison between these two alternatives is the energy mix used in recycling and virgin paper manufacture. Where the energy recovered through incineration replaces the use of fossil fuels (as in the UK), the environmental benefits are augmented, especially with regard to climate change potential and depletion of natural resources.  The type of paper and card also has a significant influence. For example, it is more beneficial from an environmental point of view to recycle high quality products such as office paper.  Looking to the future, as the UK moves to a lower-carbon energy mix, collection quality improves and recycling technology develops, then recycling will become increasingly favoured over energy recovery for all impact categories Plastics  The results confirm that mechanical recycling is the best waste management option in respect of the climate change potential, depletion of natural resources and energy demand impacts. The analysis highlights again that these benefits of recycling are mainly achieved by avoiding production of virgin plastics.  The environmental benefits are maximised by collection of good quality material (to limit the rejected fraction) and by replacement of virgin plastics on a high ratio (1 to 1).  Incineration with energy recovery performs poorly with respect to climate change impact, but pyrolysis appears to be an emerging option regarding all indicators assessed, though this was only analysed in two LCA studies.  Landfill is confirmed as having the worst environmental impacts in the majority of cases.  As the UK moves to a lower-carbon energy mix, recycling will become increasingly favoured. Biopolymers  Although biopolymers are only just emerging in the various waste streams, the limited data shows the good environmental performances of mechanical and chemical recycling regarding energy demand, depletion of natural resources and climate change potential.  However, for LCA studies that did not consider recycling as an option in the analysis, the data shows that incineration is a preferred option.  A main advantage of biopolymers that is often highlighted is the fact that some of them are degradable or compostable. Nevertheless, the analysis pointed out that composting does not appear to be advantageous for energy demand and depletion of natural resources compared to the other alternatives.  Two studies also assessed anaerobic digestion. The results for these scenarios showed that anaerobic digestion performs better than composting regarding both indicators analysed: climate change potential and energy demand. The advantage of anaerobic digestion over composting comes from the recovery of the biogas produced via electricity and heat production. Food & garden waste  Anaerobic digestion probably qualifies as the most preferable option, especially for climate change potential and depletion of natural resources. However, this conclusion should be qualified by the fact that this option was included in less than half of the selected studies.  Composting brings benefits as a result of the compost that can be used as a substitute for products such as peat or fertilisers. However, as composting is not associated with energy recovery, it generally does not perform well compared to the other options for depletion of natural resources and energy demand. Environmental benefits of recycling – 2010 update 2  Following anaerobic digestion; composting and energy recovery are generally comparable in their contribution to climate change potential.  The analysis also highlighted that home compost bins should be properly managed (aerated and with a mix of input materials) to avoid anaerobic conditions forming, leading to methane emissions.  Incineration with energy recovery presents another good environmental performance for the four indicators, despite the relatively low heating value. The key parameter, especially regarding climate change potential, is the energy mix. The benefits brought by incineration are greater if the energy produced substitutes fossil energies. Wood  Based on the lack of published LCAs, recycling of wood waste has been given little attention by LCA practitioners. As a result, a comparative analysis between the waste management options for wood waste could not be conducted.  However, from the data available, the key conclusion is that incineration with energy recovery is preferable for energy demand while recycling is preferable for climate change potential. On the other hand, landfill is to be avoided due to the associated methane emissions. Analysis of a larger set of indicators would be required in order to be able to come up with reliable evidence of the benefits of wood recycling. Textiles  There is a large gap in terms of LCAs conducted over the waste management options for textiles. Of interest is that no study has been found assessing ‘closed-loop’ recycling, whereby recycled fibres are used in the manufacture of new clothing.  Despite this lack of data, four studies were reviewed to provide a qualitative comparison of the environmental impacts of different options. The overall conclusion is that textile recycling brings substantial environmental benefits. The scale of the benefits mainly depends on the recovery routes and the material production that is avoided. General conclusion and recommendations This report reinforces the key conclusion of the first report that recycling of paper/cardboard, plastics and biopolymers for most indicators assessed provides more environmental benefits than other waste management options. For wood and textiles, more studies are needed to be able to make firmer conclusions regarding the environmental benefits of recycling for these materials. It is disappointing to note that there are very few LCAs which include an assessment of more innovative technologies such as gasification, pyrolysis and anaerobic digestion. This probably reflects the requirement for a lot of process data to model a particular option, which can be sparse in the case of the newer technologies. However, the results of the few selected studies that included anaerobic digestion and pyrolysis are very encouraging. There needs to be a stronger evidence base on certain materials (textiles, biopolymers and wood) and the more innovative EfW technologies. LCA studies need to focus on a larger set of indicators rather than only on climate change potential or energy demand. There are also LCA methodological issues that need clarification, such as the treatment of biogenic carbon and the time period considered for landfill impacts; greater clarity on these matters will help in the comparison of waste management options. Environmental benefits of recycling – 2010 update 3 Contents 1.0  Introduction.............................................................................................................................6  2.0  Methodology for the selection and assessment of LCA studies...............................................7  2.1  Literature review...................................................................................................................7  2.2  Publications selection criteria..................................................................................................7  2.2.1  The study was an LCA or LCA-like study.....................................................................7  2.2.2  The study included a comparison of two or more end-of-life scenarios for the material under study...........................................................................................................................8  2.2.3  Transparency in the assumptions made......................................................................8  2.2.4  No ambiguity in the way impacts are ascribed to materials..........................................8  2.2.5  Plausibility of the waste management options.............................................................9  2.3  Analysis of the selected studies..............................................................................................9  3.0  Results of the comparative analysis of the selected publications.........................................11  3.1  Introduction to the methodology used for results comparison................................................11  3.2  Paper and carboard.............................................................................................................12  3.2.1  Presentation...........................................................................................................12  3.2.2  Comparison between the various end-of-life options.................................................13  3.2.3  Detailed comparison between the various treatment options.....................................17  3.2.4  Conclusion..............................................................................................................29  3.2.5  Comparison with the results from the previous report edition....................................30  3.2.6  Data gaps/further research......................................................................................31  3.3  Plastics...............................................................................................................................32  3.3.1  Presentation...........................................................................................................32  3.3.2  Comparison between the various end-of-life options.................................................33  3.3.3  Detailed comparison between the various treatment options.....................................38  3.3.4  Conclusion..............................................................................................................53  3.3.5  Comparison with the results from the previous report edition....................................54  3.3.6  Data gaps/further research......................................................................................54  3.4  Biopolymers........................................................................................................................55  3.4.1  Presentation...........................................................................................................55  3.4.2  Comparison between the various end-of-life options.................................................57  3.4.3  Detailed comparison between the various treatment options.....................................60  3.4.4  Conclusion..............................................................................................................73  3.4.5  Data gaps/further research......................................................................................73  3.5  Food and garden waste.......................................................................................................74  3.5.1  Presentation...........................................................................................................74  3.5.2  Comparison between the various end-of-life options.................................................76  3.5.3  Detailed comparison between the various treatment options.....................................78  3.5.4  Conclusion..............................................................................................................90  3.5.5  Data gaps/further research......................................................................................91  3.6  Wood..................................................................................................................................92  3.6.1  Presentation...........................................................................................................92  3.6.2  Comparison between the various end-of-life options.................................................93  3.6.3  Comparison with the results from the previous report edition....................................94  3.6.4  Data gaps/further research......................................................................................94  3.7  Textiles...............................................................................................................................96  3.7.1  Presentation...........................................................................................................96  3.7.2  Comparison between the various end-of-life options.................................................97  3.7.3  Data gaps/further research......................................................................................99  4.0  Relevance of the findings in the UK context........................................................................100  4.1  The UK context.................................................................................................................100  4.1.1  Waste management..............................................................................................100  4.1.2  Environmental challenges in relation to waste management....................................100  4.1.3  Waste strategy.....................................................................................................102  4.1.4  Summing up: influence of the UK policy on end-of-life options.................................103  4.2  Relevance of findings in the UK context for paper and cardboard.........................................103  4.3  Relevance of findings in the UK context for plastics.............................................................107  Environmental benefits of recycling – 2010 update 4 4.4  Relevance of findings in the UK context for biopolymers......................................................110  4.5  Relevance of findings in the UK context for food and garden waste......................................112  4.6  Relevance of findings in the UK context for wood................................................................115  4.7  Relevance of findings in the UK context for textiles..............................................................118  Appendix 1 Description of the selected environmental indicators................................................... 126 Appendix 2 Summary of key elements from the studies on paper & cardboard...............................127 Appendix 3 Summary of key elements from the studies on plastics.................................................158 Appendix 4 Summary of key elements from the studies on biopolymers.........................................199 Appendix 5 Summary of key elements from the studies on food & garden waste...........................224 Appendix 6 List of selected studies...................................................................................................238 Appendix 7 List of rejected studies...................................................................................................241 Environmental benefits of recycling – 2010 update 5 1.0 Introduction From the point of view of sustainable development, improving waste management is essential if society’s environmental impacts are to be reduced. Identifying waste management channels with lower environmental impacts is thus a key issue. The waste hierarchy illustrated in Figure 1 is often used as a rule of thumb followed by public policies. However, a recurring theme in the debates that surround waste and resources management is the extent to which the recycling of materials offers genuine benefits to the environment. Often, critics of the policy drive towards greater recycling assert that the act of recycling may in fact have little or no benefit to the environment, suggesting that more energy may be used in getting materials to the recycling facility than is saved by the process of recycling. Figure 1 Schematic diagram showing the waste hierarchy In order to compare waste management routes in environmental terms, the Life Cycle Assessment (LCA) methodology is currently seen as the best approach to use. The strength of LCA is that the methodology allows comparison of two or more different products or processes by quantifying the service given by the products or processes. The weakness of LCA is that the results of the assessment are very sensitive to the scope of the study, to the hypothesis made, etc. To compare environmental impacts of numerous waste management routes, one solution is to review and compare existing Life Cycle Assessment (LCA) studies on waste management and to analyse the impacts of each hypothesis. To analyse the different burdens or benefits of each waste management option, WRAP (Waste & Resources Action Programme) reviews and commissions relevant LCAs. The purpose of this study is to update the Environmental Benefits of Recycling published by the WRAP in 2006. This study reviews LCA studies and compares the various possible options for waste management. This study was undertaken by Bio Intelligence Service (BIOIS) and the Copenhagen Resource Institute (CRI, former Danish Topic Centre on Waste and Resources). Collaboration with WRAP took place throughout the study. Materials covered by this study are paper and cardboard, plastics, biopolymers, food and garden waste, wood and textiles. The waste management options that are studied are composting, energy recovery (incineration, anaerobic digestion, pyrolysis and gasification), landfill and recycling. Table 1 shows the combinations of materials and treatment options covered in the study (the combinations materials/disposal options included in the previous edition are highlighted in grey). Some options, such as gasification or pyrolysis, could in theory be used for most of the fractions but the literature review has pointed out large data gaps, therefore these options could not be assessed. Environmental benefits of recycling – 2010 update 6 Table 1 Overview of the materials and treatment options under study Anaerobic  Recycling Composting Incineration  Landfill Pyrolysis Gasification digestion Paper and card x x x Plastics x x x x Biopolymers x x x x x Food and garden waste x x x x Wood  x x x Textiles x x x 2.0 Methodology for the selection and assessment of LCA studies 2.1 Literature review The main objective of this step was to identify all published LCA studies that compare two or more waste management options for one or more fractions included in the field of this review. An exhaustive review of LCA publications was carried out using the following sources of information:  International scientific journals and databases: International Journal of LCA, Science Direct, Springer  Publications by relevant worldwide organisations in waste management and life cycle assessment: National Environment Protection Agencies, European Joint Research Center (JRC), DEFRA, WRAP  BIOIS and CRI’s own databases  BIOIS and CRI’s contact network The extensive literature review led to the identification of around 220 studies. 2.2 Publications selection criteria In order to be able to choose the publications suitable and relevant for analysis, a list of selection criteria was established. The objective was to narrow the selection to transparent and high-quality studies. The criteria used for the selection were:  the study was an LCA or LCA-like study  the study included a comparison of one or more end-of-life scenarios for the material fraction under study  representation of recycling or composting among the waste management options assessed,  robustness of the publication: the publication should have been either peer reviewed or published in a scientific journal  transparency in the assumptions made  primary research and not a review of previous work  no ambiguity in the way impacts are ascribed to materials  plausibility of the waste management options Further details regarding these selection criteria are given below. 2.2.1 The study was an LCA or LCA-like study The choice was made to focus on LCA studies because LCA is currently considered as the most reliable method for analysing the environmental impacts of products and services. One of the main advantages of LCA is that it enables a quantitative evaluation of potential environmental impacts on several indicators. The LCA methodology has been standardised by the International Standards Organization (ISO) (ISO 14040 and 14044 standards). Environmental benefits of recycling – 2010 update 7 Within the requirements of ISO 14040 and 14044, the LCA must consist of the following steps:  Goal and scope definition which defines the goal and intended use of the LCA, and scopes the assessment concerning system boundaries, function and flow, required data quality, technology and assessment parameters,  Inventory analysis which consists in collecting data on inputs (resources and intermediate products) and outputs (emissions, wastes) for all the processes in the product system.  Impact assessment, phase during which inventory data on inputs and outputs are translated into indicators of potential impacts on the environment, on human health, and on the availability of natural resources.  Interpretation of results where the results of the LCI and LCIA are interpreted according to the goal of the study and where sensitivity and uncertainty analysis are performed to qualify the results and the conclusions. In addition, the ISO standards require that LCAs disclosed to the public are submitted to a critical review performed by independent LCA experts to ensure that the methods and results are scientifically and technically valid. The fulfilment of the ISO standards is thus a guarantee for quality and transparency. Except for some studies published by recognised organisations (US EPA for example), the fulfilment of the ISO 14040-series was required for the publication selection. 2.2.2 The study included a comparison of two or more end-of-life scenarios for the material under study In order to be able to conduct a comparison between various end-of-life scenarios, the systems compared must have the same functional unit and equivalent system boundaries, data quality and impact assessment methodologies. In practice, it is thus very difficult to compare LCA results for scenarios from different studies. In the present study, the choice has thus been made to conduct numerical comparisons only for scenarios analysed in a single publication. This implies that each selected study must include a comparison between at least two end-of-life options for a given fraction. This criterion was the most restrictive one and some studies of high quality and interest had to be excluded with respect to this criterion. Nevertheless, it ensured the overall coherence of the study. 2.2.3 Transparency in the assumptions made The variability of the results from one LCA study to another is often very high since results are highly dependent on the assumptions made. It is also common for studies on similar systems to lead to different conclusions. When conducting comparisons across various studies, it is therefore essential to be able to identify the key parameters that can explain why conclusions differ from one study to another. The transparency of the assumptions made was thus considered as an important criterion for the publications selection step. Most identified studies satisfied this criterion fully but a lack of information in this area was sometimes observed when the study was only reported in a journal article without an associated report. Requests were made to authors for further information but this was very difficult obtain, in particular for studies over two years old. 2.2.4 No ambiguity in the way impacts are ascribed to materials The objective of the study was to come up with an evaluation of the environmentally preferable end-of-life options for the range of considered fractions. The selected LCAs were thus required to present material-specific results. High quality LCAs comparing end-of-life options for municipal solid waste as a whole were therefore not suitable for selection. Environmental benefits of recycling – 2010 update 8

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Final report Environmental benefits of recycling – 2010 update An update to the 2006 WRAP report Environmental Benefits of Recycling, reviewing high quality Life Cycle Assessments from around the world to assess the impact of alternative waste management options for a range of materials, and discuss the findings for each material in the context of the UK. Project code: SAP097 Research date: March- December 2009 Date: March 2010 WRAP’s vision is a world without waste, where resources are used sustainably. We work with businesses and individuals to help them reap the benefits of reducing waste, developing sustainable products and using resources in an efficient way. Find out more at www.wrap.org.uk Written by: Jean-Charles Michaud, Laura Farrant and Olivier Jan from Bio Intelligence Service Birgitte Kjær and Ioannis Bakas, from the Copenhagen Resource Institute Front cover photography: WRAP, Bio Intelligence Service, and Copenhagen Resource Institute 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 steps have been taken to ensure accuracy, WRAP cannot accept responsibility or be held liable to any person 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 WRAP cannot guarantee the performance of individual products or materials. This material is copyrighted. It may be reproduced free of charge subject to the material being accurate and not used in a misleading context. The source of the material must be identified and the copyright status acknowledged. This material must not be used to endorse or used to suggest WRAP’s endorsement of a commercial product or service. For more detail, please refer to WRAP’s Terms & Conditions on its web site: www.wrap.org.uk Executive summary Context In 2006, WRAP (Waste & Resources Action Programme) published a major research report, Environmental Benefits of Recycling, based on an international review of life cycle analyses (LCA) that evaluated the impact on the environment of recycling, landfilling or incineration of key materials in UK waste streams. The review assessed 55 ‘state of the art’ LCAs on paper and cardboard, glass, plastics, aluminium, steel, wood and aggregates. The conclusion was clear – most studies show that recycling offers more environmental benefits and lower environmental impacts than the other waste management options. With the emergence of new waste management options and new waste streams in the last three years, WRAP has decided to update this report and ensure that policy makers and stakeholders are aware of the latest conclusions from LCA data on waste management options. The methodology behind the new report remains the same1 – careful screening of over 200 LCAs published worldwide since 2006 against strict criteria to focus on only the highest quality analyses. However, the scope of the review was changed in several ways:  New waste management technologies were added: composting and energy from waste (EfW) technologies such as anaerobic digestion, pyrolysis and gasification.  New waste streams/materials were added: food waste, garden waste, textiles and biopolymers.  Some materials were excluded from further analyses – aluminium, steel, glass and aggregates – as the results of the first study (that recycling is the preferred waste management option for these materials) are not impacted by the new technologies. In summary, the material / technology combinations of this study are shown in the following table (those included in the first report are highlighted in grey) Anaerobic  Recycling Composting Incineration  Landfill Pyrolysis Gasification digestion Paper and card x x x Plastics x x x x Biopolymers x x x x x Food and garden waste x x x x Wood  x x x Textiles x x x The key impact categories used for the assessment of the different waste management options were:  depletion of natural resources  climate change potential  cumulative energy demand  water consumption 1 The criteria used for the selection were: (i) the study had to be an LCA or LCA-like; (ii) includes a comparison of two or more end-of-life scenarios for the material fraction under study; (iii) representation of recycling or composting among the waste management options assessed; (iv) robustness of the publication, either peer reviewed or published in a scientific journal; (v) transparency in the assumptions made; (vi) primary research and not a review of previous work; (vii) no ambiguity in the way impacts are ascribed to materials; (viii) plausibility of the waste management options. Environmental benefits of recycling – 2010 update 1 Key conclusions from the LCA studies Because of the international nature of the study, the review has attempted to interpret the results in terms of UK impact. The key parameter in this respect in the energy mix used in the scope of a specific LCA, which might be quite different from that in the UK. The key conclusions are outlined below by material/waste type. Paper and cardboard  The results of the first study are confirmed in that landfilling of paper and cardboard is the least preferable option, particularly from a climate change potential and energy demand perspective.  The comparison between recycling and incineration appears more complex, as better energy recovery efficiencies have been built into the more recent LCAs. In general, the data shows that recycling is preferable for energy demand and water consumption, but they are comparable for climate change.  The key parameter affecting the comparison between these two alternatives is the energy mix used in recycling and virgin paper manufacture. Where the energy recovered through incineration replaces the use of fossil fuels (as in the UK), the environmental benefits are augmented, especially with regard to climate change potential and depletion of natural resources.  The type of paper and card also has a significant influence. For example, it is more beneficial from an environmental point of view to recycle high quality products such as office paper.  Looking to the future, as the UK moves to a lower-carbon energy mix, collection quality improves and recycling technology develops, then recycling will become increasingly favoured over energy recovery for all impact categories Plastics  The results confirm that mechanical recycling is the best waste management option in respect of the climate change potential, depletion of natural resources and energy demand impacts. The analysis highlights again that these benefits of recycling are mainly achieved by avoiding production of virgin plastics.  The environmental benefits are maximised by collection of good quality material (to limit the rejected fraction) and by replacement of virgin plastics on a high ratio (1 to 1).  Incineration with energy recovery performs poorly with respect to climate change impact, but pyrolysis appears to be an emerging option regarding all indicators assessed, though this was only analysed in two LCA studies.  Landfill is confirmed as having the worst environmental impacts in the majority of cases.  As the UK moves to a lower-carbon energy mix, recycling will become increasingly favoured. Biopolymers  Although biopolymers are only just emerging in the various waste streams, the limited data shows the good environmental performances of mechanical and chemical recycling regarding energy demand, depletion of natural resources and climate change potential.  However, for LCA studies that did not consider recycling as an option in the analysis, the data shows that incineration is a preferred option.  A main advantage of biopolymers that is often highlighted is the fact that some of them are degradable or compostable. Nevertheless, the analysis pointed out that composting does not appear to be advantageous for energy demand and depletion of natural resources compared to the other alternatives.  Two studies also assessed anaerobic digestion. The results for these scenarios showed that anaerobic digestion performs better than composting regarding both indicators analysed: climate change potential and energy demand. The advantage of anaerobic digestion over composting comes from the recovery of the biogas produced via electricity and heat production. Food & garden waste  Anaerobic digestion probably qualifies as the most preferable option, especially for climate change potential and depletion of natural resources. However, this conclusion should be qualified by the fact that this option was included in less than half of the selected studies.  Composting brings benefits as a result of the compost that can be used as a substitute for products such as peat or fertilisers. However, as composting is not associated with energy recovery, it generally does not perform well compared to the other options for depletion of natural resources and energy demand. Environmental benefits of recycling – 2010 update 2  Following anaerobic digestion; composting and energy recovery are generally comparable in their contribution to climate change potential.  The analysis also highlighted that home compost bins should be properly managed (aerated and with a mix of input materials) to avoid anaerobic conditions forming, leading to methane emissions.  Incineration with energy recovery presents another good environmental performance for the four indicators, despite the relatively low heating value. The key parameter, especially regarding climate change potential, is the energy mix. The benefits brought by incineration are greater if the energy produced substitutes fossil energies. Wood  Based on the lack of published LCAs, recycling of wood waste has been given little attention by LCA practitioners. As a result, a comparative analysis between the waste management options for wood waste could not be conducted.  However, from the data available, the key conclusion is that incineration with energy recovery is preferable for energy demand while recycling is preferable for climate change potential. On the other hand, landfill is to be avoided due to the associated methane emissions. Analysis of a larger set of indicators would be required in order to be able to come up with reliable evidence of the benefits of wood recycling. Textiles  There is a large gap in terms of LCAs conducted over the waste management options for textiles. Of interest is that no study has been found assessing ‘closed-loop’ recycling, whereby recycled fibres are used in the manufacture of new clothing.  Despite this lack of data, four studies were reviewed to provide a qualitative comparison of the environmental impacts of different options. The overall conclusion is that textile recycling brings substantial environmental benefits. The scale of the benefits mainly depends on the recovery routes and the material production that is avoided. General conclusion and recommendations This report reinforces the key conclusion of the first report that recycling of paper/cardboard, plastics and biopolymers for most indicators assessed provides more environmental benefits than other waste management options. For wood and textiles, more studies are needed to be able to make firmer conclusions regarding the environmental benefits of recycling for these materials. It is disappointing to note that there are very few LCAs which include an assessment of more innovative technologies such as gasification, pyrolysis and anaerobic digestion. This probably reflects the requirement for a lot of process data to model a particular option, which can be sparse in the case of the newer technologies. However, the results of the few selected studies that included anaerobic digestion and pyrolysis are very encouraging. There needs to be a stronger evidence base on certain materials (textiles, biopolymers and wood) and the more innovative EfW technologies. LCA studies need to focus on a larger set of indicators rather than only on climate change potential or energy demand. There are also LCA methodological issues that need clarification, such as the treatment of biogenic carbon and the time period considered for landfill impacts; greater clarity on these matters will help in the comparison of waste management options. Environmental benefits of recycling – 2010 update 3 Contents 1.0  Introduction.............................................................................................................................6  2.0  Methodology for the selection and assessment of LCA studies...............................................7  2.1  Literature review...................................................................................................................7  2.2  Publications selection criteria..................................................................................................7  2.2.1  The study was an LCA or LCA-like study.....................................................................7  2.2.2  The study included a comparison of two or more end-of-life scenarios for the material under study...........................................................................................................................8  2.2.3  Transparency in the assumptions made......................................................................8  2.2.4  No ambiguity in the way impacts are ascribed to materials..........................................8  2.2.5  Plausibility of the waste management options.............................................................9  2.3  Analysis of the selected studies..............................................................................................9  3.0  Results of the comparative analysis of the selected publications.........................................11  3.1  Introduction to the methodology used for results comparison................................................11  3.2  Paper and carboard.............................................................................................................12  3.2.1  Presentation...........................................................................................................12  3.2.2  Comparison between the various end-of-life options.................................................13  3.2.3  Detailed comparison between the various treatment options.....................................17  3.2.4  Conclusion..............................................................................................................29  3.2.5  Comparison with the results from the previous report edition....................................30  3.2.6  Data gaps/further research......................................................................................31  3.3  Plastics...............................................................................................................................32  3.3.1  Presentation...........................................................................................................32  3.3.2  Comparison between the various end-of-life options.................................................33  3.3.3  Detailed comparison between the various treatment options.....................................38  3.3.4  Conclusion..............................................................................................................53  3.3.5  Comparison with the results from the previous report edition....................................54  3.3.6  Data gaps/further research......................................................................................54  3.4  Biopolymers........................................................................................................................55  3.4.1  Presentation...........................................................................................................55  3.4.2  Comparison between the various end-of-life options.................................................57  3.4.3  Detailed comparison between the various treatment options.....................................60  3.4.4  Conclusion..............................................................................................................73  3.4.5  Data gaps/further research......................................................................................73  3.5  Food and garden waste.......................................................................................................74  3.5.1  Presentation...........................................................................................................74  3.5.2  Comparison between the various end-of-life options.................................................76  3.5.3  Detailed comparison between the various treatment options.....................................78  3.5.4  Conclusion..............................................................................................................90  3.5.5  Data gaps/further research......................................................................................91  3.6  Wood..................................................................................................................................92  3.6.1  Presentation...........................................................................................................92  3.6.2  Comparison between the various end-of-life options.................................................93  3.6.3  Comparison with the results from the previous report edition....................................94  3.6.4  Data gaps/further research......................................................................................94  3.7  Textiles...............................................................................................................................96  3.7.1  Presentation...........................................................................................................96  3.7.2  Comparison between the various end-of-life options.................................................97  3.7.3  Data gaps/further research......................................................................................99  4.0  Relevance of the findings in the UK context........................................................................100  4.1  The UK context.................................................................................................................100  4.1.1  Waste management..............................................................................................100  4.1.2  Environmental challenges in relation to waste management....................................100  4.1.3  Waste strategy.....................................................................................................102  4.1.4  Summing up: influence of the UK policy on end-of-life options.................................103  4.2  Relevance of findings in the UK context for paper and cardboard.........................................103  4.3  Relevance of findings in the UK context for plastics.............................................................107  Environmental benefits of recycling – 2010 update 4 4.4  Relevance of findings in the UK context for biopolymers......................................................110  4.5  Relevance of findings in the UK context for food and garden waste......................................112  4.6  Relevance of findings in the UK context for wood................................................................115  4.7  Relevance of findings in the UK context for textiles..............................................................118  Appendix 1 Description of the selected environmental indicators................................................... 126 Appendix 2 Summary of key elements from the studies on paper & cardboard...............................127 Appendix 3 Summary of key elements from the studies on plastics.................................................158 Appendix 4 Summary of key elements from the studies on biopolymers.........................................199 Appendix 5 Summary of key elements from the studies on food & garden waste...........................224 Appendix 6 List of selected studies...................................................................................................238 Appendix 7 List of rejected studies...................................................................................................241 Environmental benefits of recycling – 2010 update 5 1.0 Introduction From the point of view of sustainable development, improving waste management is essential if society’s environmental impacts are to be reduced. Identifying waste management channels with lower environmental impacts is thus a key issue. The waste hierarchy illustrated in Figure 1 is often used as a rule of thumb followed by public policies. However, a recurring theme in the debates that surround waste and resources management is the extent to which the recycling of materials offers genuine benefits to the environment. Often, critics of the policy drive towards greater recycling assert that the act of recycling may in fact have little or no benefit to the environment, suggesting that more energy may be used in getting materials to the recycling facility than is saved by the process of recycling. Figure 1 Schematic diagram showing the waste hierarchy In order to compare waste management routes in environmental terms, the Life Cycle Assessment (LCA) methodology is currently seen as the best approach to use. The strength of LCA is that the methodology allows comparison of two or more different products or processes by quantifying the service given by the products or processes. The weakness of LCA is that the results of the assessment are very sensitive to the scope of the study, to the hypothesis made, etc. To compare environmental impacts of numerous waste management routes, one solution is to review and compare existing Life Cycle Assessment (LCA) studies on waste management and to analyse the impacts of each hypothesis. To analyse the different burdens or benefits of each waste management option, WRAP (Waste & Resources Action Programme) reviews and commissions relevant LCAs. The purpose of this study is to update the Environmental Benefits of Recycling published by the WRAP in 2006. This study reviews LCA studies and compares the various possible options for waste management. This study was undertaken by Bio Intelligence Service (BIOIS) and the Copenhagen Resource Institute (CRI, former Danish Topic Centre on Waste and Resources). Collaboration with WRAP took place throughout the study. Materials covered by this study are paper and cardboard, plastics, biopolymers, food and garden waste, wood and textiles. The waste management options that are studied are composting, energy recovery (incineration, anaerobic digestion, pyrolysis and gasification), landfill and recycling. Table 1 shows the combinations of materials and treatment options covered in the study (the combinations materials/disposal options included in the previous edition are highlighted in grey). Some options, such as gasification or pyrolysis, could in theory be used for most of the fractions but the literature review has pointed out large data gaps, therefore these options could not be assessed. Environmental benefits of recycling – 2010 update 6 Table 1 Overview of the materials and treatment options under study Anaerobic  Recycling Composting Incineration  Landfill Pyrolysis Gasification digestion Paper and card x x x Plastics x x x x Biopolymers x x x x x Food and garden waste x x x x Wood  x x x Textiles x x x 2.0 Methodology for the selection and assessment of LCA studies 2.1 Literature review The main objective of this step was to identify all published LCA studies that compare two or more waste management options for one or more fractions included in the field of this review. An exhaustive review of LCA publications was carried out using the following sources of information:  International scientific journals and databases: International Journal of LCA, Science Direct, Springer  Publications by relevant worldwide organisations in waste management and life cycle assessment: National Environment Protection Agencies, European Joint Research Center (JRC), DEFRA, WRAP  BIOIS and CRI’s own databases  BIOIS and CRI’s contact network The extensive literature review led to the identification of around 220 studies. 2.2 Publications selection criteria In order to be able to choose the publications suitable and relevant for analysis, a list of selection criteria was established. The objective was to narrow the selection to transparent and high-quality studies. The criteria used for the selection were:  the study was an LCA or LCA-like study  the study included a comparison of one or more end-of-life scenarios for the material fraction under study  representation of recycling or composting among the waste management options assessed,  robustness of the publication: the publication should have been either peer reviewed or published in a scientific journal  transparency in the assumptions made  primary research and not a review of previous work  no ambiguity in the way impacts are ascribed to materials  plausibility of the waste management options Further details regarding these selection criteria are given below. 2.2.1 The study was an LCA or LCA-like study The choice was made to focus on LCA studies because LCA is currently considered as the most reliable method for analysing the environmental impacts of products and services. One of the main advantages of LCA is that it enables a quantitative evaluation of potential environmental impacts on several indicators. The LCA methodology has been standardised by the International Standards Organization (ISO) (ISO 14040 and 14044 standards). Environmental benefits of recycling – 2010 update 7 Within the requirements of ISO 14040 and 14044, the LCA must consist of the following steps:  Goal and scope definition which defines the goal and intended use of the LCA, and scopes the assessment concerning system boundaries, function and flow, required data quality, technology and assessment parameters,  Inventory analysis which consists in collecting data on inputs (resources and intermediate products) and outputs (emissions, wastes) for all the processes in the product system.  Impact assessment, phase during which inventory data on inputs and outputs are translated into indicators of potential impacts on the environment, on human health, and on the availability of natural resources.  Interpretation of results where the results of the LCI and LCIA are interpreted according to the goal of the study and where sensitivity and uncertainty analysis are performed to qualify the results and the conclusions. In addition, the ISO standards require that LCAs disclosed to the public are submitted to a critical review performed by independent LCA experts to ensure that the methods and results are scientifically and technically valid. The fulfilment of the ISO standards is thus a guarantee for quality and transparency. Except for some studies published by recognised organisations (US EPA for example), the fulfilment of the ISO 14040-series was required for the publication selection. 2.2.2 The study included a comparison of two or more end-of-life scenarios for the material under study In order to be able to conduct a comparison between various end-of-life scenarios, the systems compared must have the same functional unit and equivalent system boundaries, data quality and impact assessment methodologies. In practice, it is thus very difficult to compare LCA results for scenarios from different studies. In the present study, the choice has thus been made to conduct numerical comparisons only for scenarios analysed in a single publication. This implies that each selected study must include a comparison between at least two end-of-life options for a given fraction. This criterion was the most restrictive one and some studies of high quality and interest had to be excluded with respect to this criterion. Nevertheless, it ensured the overall coherence of the study. 2.2.3 Transparency in the assumptions made The variability of the results from one LCA study to another is often very high since results are highly dependent on the assumptions made. It is also common for studies on similar systems to lead to different conclusions. When conducting comparisons across various studies, it is therefore essential to be able to identify the key parameters that can explain why conclusions differ from one study to another. The transparency of the assumptions made was thus considered as an important criterion for the publications selection step. Most identified studies satisfied this criterion fully but a lack of information in this area was sometimes observed when the study was only reported in a journal article without an associated report. Requests were made to authors for further information but this was very difficult obtain, in particular for studies over two years old. 2.2.4 No ambiguity in the way impacts are ascribed to materials The objective of the study was to come up with an evaluation of the environmentally preferable end-of-life options for the range of considered fractions. The selected LCAs were thus required to present material-specific results. High quality LCAs comparing end-of-life options for municipal solid waste as a whole were therefore not suitable for selection. Environmental benefits of recycling – 2010 update 8

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