Waste Reprocessing Infrastructure in Scotland

Appendix 1 – Methodology

Introduction

The primary data sources for this work are the SEPA Waste from All Sources (WFAS) database^[100] and the SEPA Waste Sites and Capacity Tool^[101].

SEPA Waste Sites and Capacity Tool offer the finest level of granularity for assessing specific materials, but they require careful processing to deal with double counting that could arise from the inclusion of waste which is transferred between sites, as well as due to potential errors in the way data has been recorded by individual sites.

High-level statistics derived from SEPA WFAS are already processed by SEPA in order to limit double counting of waste, and in many of the specific material cases the classifications used there could be applied directly.

Materials

The specific materials investigated in this work are:

• Plastic
• Aluminium
• Steel
• Paper and Card
• Glass
• Wood
• Fibre-based composites
• Electronic waste
• Batteries
• Renewable energy installations
• Organic waste
• Textiles
• Mattresses
• Construction materials (concrete)
• Tyres

The materials identified are those which arise in the greatest quantities within Scotland (excluding soils) and where the greatest amount of data and information on their associated reprocessing landscapes is available.

Waste arisings

Data on waste arisings were sourced from the SEPA Waste from all Sources (WFAS) dataset. SEPA WFAS provides data for 33 waste categories, matching the European Waste Classification Statistic (EWC-Stat) waste types. A direct or close match between materials and EWC-stat category was found in a majority of cases (10 materials; see Table A1). WFAS data was used to establish a tonnage of each material collected separately (‘generated’), as well as arisings through other treatment of mixed materials.

As some materials are also contained within residual waste, Zero Waste Scotland Household Waste Composition Analysis Report^[102] was used to provide an estimated tonnage of each material within residual waste from households where relevant which could be available for processing if separated properly for recycling. Due to lack of relevant waste composition data for residual waste from Commercial & Industrial (C&I) and Construction & Demolition (C&D) sectors, it was not possible to estimate the potential tonnage of priority materials in residual waste from these sources.

Fibre-based composites (drink cartons), mattresses, construction materials (concrete) and renewable energy installations do not align with EWC-Stat categories. For textile waste, whilst an EWC-Stat category exists, the information provided by the SEPA WFAS data against this category is incomplete and was therefore not used.

In order to determine waste arisings for fibre-based composites and construction materials, site returns data was used, based on matching of EWC codes and elimination of sites which did not carry out recycling/reprocessing (see below). The EWC code mapping for each of these materials is given in Table A1.

For mattresses, renewable energy installations and textiles, EWC codes cover multiple waste types and are not exclusive to these particular materials, and are therefore not best suited for determining arisings. In these cases, other published sources have been used to establish waste arisings as referenced in the relevant sections of the report.

Table A1: Summary of EWC-stat, EWC codes and Other streams categories used to calculate arisings and capacity estimates for materials considered in this report. Starred (*) items indicate that caveats apply to the use of the stated method of calculation of arisings; these are detailed in the notes column. Starred (*) EWC codes indicate that the waste is considered hazardous.

Material

Plastic

EWC-stat categories

Plastic

Other streams

Household and similar wastes

Other streams type

Dense Plastic, Plastic films and flexibles

EWC codes

02 01 04; 07 02 13; 12 01 05; 15 01 02;16 01 19; 17 02 03; 17 02 04*; 19 12 04; 20 01 39

EWC Description

Agricultural and Food Production: Waste plastics (except packaging); Organic Chemical Processes: Waste plastic; Shaping/Treatment Of Metals And Plastics: Plastics shavings and turnings; Packaging, Cloths, Filter Materials: Plastic packaging; Not Otherwise Specified: Plastic; C&D Waste and Asbestos: Plastic; C&D Waste and Asbestos: Glass, plastic and wood containing or contaminated with hazardous substances; Waste/Water Treatment and Water Industry: Plastic and rubber; Municipal And Similar Commercial Wastes: Plastics

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis^[103]

Material

Alu-minium

EWC-stat categories

Metallic wastes, non-ferrous; Metallic wastes, mixed ferrous and non-ferrous

Other streams

Household and similar wastes

Other streams type

Aluminium drink cans; Aluminium packaging

EWC codes

02 01 10; 12 01 03; 12 01 04; 15 01 04; 16 01 18; 17 04 02; 19 10 02; 19 12 03; 20 01 40

EWC Description

Agricultural and Food Production: Waste metal; Shaping/Treatment of Metals and Plastics: Non-ferrous metal filings and turnings; Shaping/ Treatment of Metals and Plastics: Non-ferrous metal dust and particles; Packaging, Cloths, Filter Materials: Metallic packaging; Not Otherwise Specified: Non-ferrous metal; C&D Waste and Asbestos: Aluminium; Waste/Water Treatment and Water Industry: Non-ferrous waste; Waste/Water Treatment and Water Industry: Non-ferrous metal; Municipal and Similar Commercial Wastes: Metals

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis.

Material

Steel

EWC-stat categories

Metallic wastes, ferrous; Metallic wastes, mixed ferrous and non-ferrous

Household and similar wastes Steel drink cans; Other ferrous packaging

EWC codes

02 01 10; 12 01 01; 12 01 02; 15 01 04; 16 01 17; 17 04 05; 17 04 09*; 19 01 02; 19 10 01; 19 12 02; 20 01 40

EWC Description

Agricultural And Food Production: waste metal; Shaping/Treatment Of Metals And Plastics: ferrous metal filings and turnings; Shaping/Treatment Of Metals And Plastics: ferrous metal dust and particles; Packaging, Cloths, Filter Materials: metallic packaging; Not Otherwise Specified: ferrous metal; C&D Waste And Asbestos: iron and steel; C&D Waste And Asbestos: metal waste contaminated with hazardous substances: Waste/Water Treatment And Water Industry: ferrous materials removed from bottom ash; Waste/Water Treatment And Water Industry: iron and steel waste; Waste/Water Treatment And Water Industry: ferrous metal; Municipal And Similar Commercial Wastes: metals

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis.

Material

Paper and Card

EWC-stat categories

Paper and Card

Other streams

Household and similar wastes

Newspaper, magazines and directories; Other recyclable paper; Recyclable paper packaging; Non-recyclable paper; Thin (Grey) Card Packaging; Thick (Brown) corrugated cardboard packaging; Cartons and other card/plastic laminate packaging; Other card; Heavily contaminated card & other composite card

EWC codes

15 01 01; 19 12 01; 20 01 01

EWC Description

Packaging, Cloths, Filter Materials: paper and cardboard packaging; Waste/Water Treatment And Water Industry: paper and cardboard; Municipal And Similar Commercial Wastes: paper and cardboard

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis

Material

Glass

EWC-stat categories

Glass wastes

Other streams

Household and similar wastes

Drinks bottles; Other glass packaging; Non-packaging glass

EWC codes

10 11 03; 10 11 11*; 10 11 12; 15 01 07; 16 01 20; 17 02 02; 17 02 04*; 19 12 05; 20 01 02

EWC Description

Thermal Process Waste (Inorganic): waste glass-based fibrous materials; Thermal Process Waste (Inorganic): waste glass in small particles and glass powder containing heavy metals (for example from cathode ray tubes); Thermal Process Waste (Inorganic): waste glass other than those mentioned in 10 11 11; Packaging, Cloths, Filter Materials: glass packaging; Not Otherwise Specified: glass; C&D Waste And Asbestos: glass; C&D Waste And Asbestos: glass, plastic and wood containing or contaminated with hazardous substances; Waste/Water Treatment And Water Industry: glass; Municipal And Similar Commercial Wastes: glass

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis

Material

Wood

EWC-stat categories

Wood wastes

Other streams

Household and similar wastes Wooden packaging; Non-packaging wood

EWC codes

02 01 03; 02 01 07; 03 01 04*; 03 01 05; 03 03 01; 15 01 03; 15 01 10*; 17 02 01; 17 02 04*; 19 12 06*; 19 12 07; 20 01 37*; 20 01 38

EWC Description

Agricultural And Food Production: plant-tissue waste; Agricultural And Food Production: wastes from forestry; Wood And Paper Production: waste bark and cork; Wood And Paper Production: sawdust, shavings, cuttings, wood, particle board and veneer containing hazardous substances; Wood And Paper Production: sawdust, shavings, cuttings, wood, particle board and veneer other than those mentioned in 03 01 04; Wood And Paper Production: waste bark and wood; Packaging, Cloths, Filter Materials: wooden packaging; Packaging, Cloths, Filter Materials: packaging containing residues of or contaminated by hazardous substances; C&D Waste And Asbestos: wood; C&D Waste And Asbestos: glass, plastic and wood containing or contaminated with hazardous substances; Waste/Water Treatment And Water Industry: wood containing hazardous substances; Waste/Water Treatment And Water Industry: wood other than that mentioned in 19 12 06; Municipal And Similar Commercial Wastes: wood containing hazardous substances; Municipal And Similar Commercial Wastes: wood other than that mentioned in 20 01 37; Municipal And Similar Commercial Wastes: biodegradable waste

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis.

Material

Fibre-based composites

EWC-stat categories

Composite packaging

Other streams

Household and similar wastes

Cartons and other card/plastic laminate packaging

EWC codes

15 01 05

EWC Description

Packaging, Cloths, Filter Materials: composite packaging

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis. Due to the small tonnage of the relevant EWC code coupled with the limitations in the public data available from SEPA on waste infrastructure capacity we are unable to provide a confident capacity figure exclusive to fibre-based composites waste.

Material

Electronic Waste

EWC-stat categories

Discarded equipment (excluding discarded vehicles)

Other streams

Household and similar wastes

EWC codes

16 02 09* 16 02 13* 16 02 14 16 02 15* 16 02 16 20 01 35* 20 01 36

EWC Description

Not Otherwise Specified: transformers and capacitors containing PCBs; Not Otherwise Specified: discarded equipment containing hazardous components other than those mentioned in 16 02 09 to 16 02 12; Not Otherwise Specified: discarded equipment other than those mentioned in 16 02 09 to 16 02 13; Not Otherwise Specified: hazardous components removed from discarded equipment; Not Otherwise Specified: components removed from discarded equipment other than those mentioned in 16 02 15; Municipal And Similar Commercial Wastes: discarded electrical and electronic equipment other than those mentioned in 20 01 21 and 20 01 23 containing hazardous components; Municipal And Similar Commercial Wastes: discarded electrical and electronic equipment other than those mentioned in 20 01 21, 20 01 23 and 20 01 35

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis

Material

Batteries

EWC-stat categories

Batteries and accumulators wastes

Other streams

Household and similar wastes

Batteries

EWC codes

16 06 01*; 16 06 02*; 16 06 03*; 16 06 04; 16 06 05; 16 06 06*; 20 01 33*; 20 01 34

EWC Description

Not Otherwise Specified: lead batteries; Not Otherwise Specified: Ni-Cd batteries; Not Otherwise Specified: mercury-containing batteries; Not Otherwise Specified: alkaline batteries (except 16 06 03); Not Otherwise Specified: other batteries and accumulators; Not Otherwise Specified: separately collected electrolyte from batteries and accumulators; Municipal And Similar Commercial Wastes: batteries and accumulators included in 16 06 01, 16 06 02 or 16 06 03 and unsorted batteries and accumulators containing these batteries; Municipal And Similar Commercial Wastes: batteries and accumulators other than those mentioned in 20 01 33

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis

Material

Organic waste

EWC-stat categories

Animal and mixed food waste; Vegetal wastes

Other streams

Household and similar wastes Mowing, cutting and pruning garden waste; Food (avoidable) - in packaging; Drinks (avoidable) - in packaging; Food and drink (avoidable) – loose; Inedible parts of food; Cooking oil

EWC codes

02 01 01; 02 01 02; 02 02 01; 02 02 02; 02 02 03; 02 02 04; 02 03 01; 02 03 04; 02 05 01; 02 06 01; 02 07 01; 02 07 04; 20 01 08; 20 02 01; 20 02 02

EWC Description

Agricultural And Food Production: sludges from washing and cleaning; Agricultural And Food Production: animal-tissue waste; Agricultural And Food Production: sludges from washing and cleaning; Agricultural And Food Production: animal-tissue waste; Agricultural And Food Production: materials unsuitable for consumption or processing; Agricultural And Food Production: sludges from on-site effluent treatment; Agricultural And Food Production: sludges from washing, cleaning, peeling, centrifuging and separation; Agricultural And Food Production: materials unsuitable for consumption or processing; Agricultural And Food Production: materials unsuitable for consumption or processing; Agricultural And Food Production: materials unsuitable for consumption or processing; Agricultural And Food Production: wastes from washing, cleaning and mechanical reduction of raw materials; Agricultural And Food Production: materials unsuitable for consumption or processing; Municipal And Similar Commercial Wastes: biodegradable kitchen and canteen waste; Municipal And Similar Commercial Wastes: biodegradable waste; Municipal And Similar Commercial Wastes: soil and stones

Notes

Other streams breakdown based on Zero Waste Scotland HH waste composition analysis

Material

Tyres

EWC-stat categories

Rubber wastes

EWC codes

16 01 03; 19 12 04

EWC Description

Not Otherwise Specified: end-of-life tyres; Waste/Water Treatment And Water Industry: plastic and rubber

Notes

EWC-stat "Rubber wastes"

Material

Construction materials (concrete)

EWC-stat categories

Mineral waste from construction and demolition

EWC codes

10 13 14;17 01 01; 17 01 06*

EWC Description

Thermal Process Waste (Inorganic): waste concrete and concrete sludge; C&D Waste And Asbestos: concrete; C&D Waste And Asbestos: mixtures of, or separate fractions of concrete, bricks, tiles and ceramics containing hazardous substances

Notes

Material contained within ‘mineral waste from construction and demolition’ category. EWC codes included are not exclusively concrete waste.

Reprocessing capacity

For the 10 materials with a matching EWC-Stat waste type, SEPA WFAS data shows the destination of the waste: disposed, recovered, recycled (domestic) and recycled (export). For these materials, trends in arisings and destinations were investigated for the period from 2016 to 2023 (no data for 2019/2020 due to cyber-attack on SEPA), providing insights into the proportion of waste remaining in Scotland to be reprocessed.

To provide an overview of recycling and reprocessing infrastructure in Scotland, information on current infrastructure was sourced from the SEPA Waste Sites and Capacity Tool. This tool is updated annually, and provides data on facility types, geographical location, permitted capacities, waste types, tonnages, and methods of treatment for licensed sites required to submit data returns to SEPA.

For most all materials, with the exception of mattresses, renewable energy installations and textiles, site returns data was analysed to identify inputs of the specific EWC codes matching the material (see Table A1). Data contained in Table B (inputs – licenced sites) and Table D (outputs) was used to determine the number of sites handling each material (including transfers and storage). SEPA National Waste Team provided additional commentary and insight into the nature of operations by these sites.

The following data filtering process was then used to identify the number of sites which reported to SEPA that they had treated the material of interest on-site in 2023:

SEPA Site Returns -> Licenced Site Returns -> Table C (treated) -> Material EWC codes

SEPA provides the following definitions for methods by which this waste is managed:

• Management method: BT (Biological treatment), Correct use in Table C: All wastes undergoing biological treatment on-site, e.g. anaerobic digestion, bio-treatment of sludges.
• Management method: CT (Chemical treatment), Correct use in Table C: All wastes undergoing chemical treatment on-site, e.g. neutralisation, oil regeneration.
• Management method: CP (Composted), Correct use in Table C: All wastes undergoing composting on-site (including in-vessel and windrow).
• Management method: CS (Crushed and screened), Correct use in Table C: All wastes crushed and screened on-site, e.g. rubble and glass into aggregate.
• Management method: PT (Physical treatment), Correct use in Table C: All wastes undergoing primarily physical treatment on-site, examples include:
  • Manual/mechanical sorting of residual and comingled waste and mixed skips
  • Stripping down vehicles and de-polluting engines
  • Shredding/fragmentising metal waste
  • Mechanical biological treatment (MBT) of residual waste
  • Centrifugation, autoclaving and pyrolysis
• Management method: RC (Recycled), Correct use in Table C: All wastes that are recycled to a final product or end-of-waste criteria on-site.
• Management method: OT (Other treatment), Correct use in Table C: All wastes undergoing any other kind of treatment on-site not specified above.

All of these management methods are considered as treatment for the purposes of this report. SEPA National Waste Team provided additional commentary and insight into the nature of treatment at these sites. These sites are listed in Appendix 4.

Data on Accredited Reprocessors was also used in the analysis. For Packaging Waste (Plastic, Glass, Aluminium, Steel, Paper and Card, Wood and Fibre-based composite packaging) as well as Batteries and WEEE, accredited reprocessors recycle or recover waste packaging discarded by United Kingdom (UK) businesses and households. They sell electronic packaging recovery notes (PRNs) to packaging producers and reinvest the income into the recycling of packaging.

A register of accredited reprocessors is available on the National Waste Packaging Database and WEEE public registers and a list of the accredited reprocessors registered with Scottish registration is included in Appendix 3.

Capacity gap

The available information on waste arisings, destination of these wastes and the number of facilities actively treating this waste formed a picture of the overall domestic reprocessing landscape for each material, highlighting the materials for which significant amounts are recycled outside of Scotland. Although commentary has been provided, a specific capacity gap (indicating a potential need for reprocessing infrastructure in Scotland) for each material stream has not been calculated as materials flow out of Scotland for reprocessing for various reasons (e.g. existing contracts, economics, established end markets etc.), meaning that the fact material is not reprocessed in Scotland does not necessarily indicate that infrastructure capacity is not available. Extensive industry engagement would be required to develop sector specific understanding, which has not been included as part of this desktop-based report.