Final Report Compositional Analysis of Kerbside Collected ... · Compositional Analysis of Kerbside Collected Small WEEE 6 1.0 Trial Objectives The objectives stated by WRAP were

Final Report

Compositional Analysis of Kerbside Collected Small WEEE

This report describes the dismantling of a large sample of small household WEEE items collected over a nine week period in Bury St Edmunds, Suffolk. It focuses on an analysis of the separated materials found during the trial, in particular the batteries and plastic components.

Project code: MDD009 Research date: April – June 2008 Date: February 2009

WRAP helps individuals, businesses and local authorities to reduce waste and recycle more, making better use of resources and helping to tackle climate change.

Written by: Keith Freegard and Michael Claes, Axion Recycling Ltd.

Front cover photography: Example of dismantled electric iron WRAP and Axion Recycling Ltd 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

Compositional Analysis of Kerbside Collected Small WEEE 3

Executive summary A kerbside collection trial was carried out across 20,000 households in Bury St Edmunds, Suffolk in order to assess the potential of this collection method as a means to capture small domestic appliances separately from ‘black-bag’ household waste. The trial was carried out over a nine week period and residents were sent a letter to explain the type and size of WEEE items that would be accepted in the kerbside collection trial. Nearly three tonnes of small WEEE items were collected in the trial, a total of 2,101 individual items. The skips of items were sorted and catalogued by product type and WEEE category, before being shipped for dismantling and further analysis. The most common items found in this collection were kettles, phones, irons, toasters and assorted chargers/transformers. It was noted that, once thrown into a bulk waste skip, the damage and contamination of the products effectively prevented any potential for re-use, even though many items were seen to be in working order. Manual dismantling of a sample of 300 items was used to measure the material composition of the collected WEEE material. This revealed that around half of the mass was light ferrous metal and a third was plastic components, with printed circuit boards accounting for 8% of the collected mass. The plastic components were further analysed by polymer type and for the presence of brominated flame-retardant additives. The whole sample was checked for battery content and these were removed from the WEEE items, weighed and sent for further analysis by battery type. In total 9.26kg of batteries were removed from the whole sample, just 0.3% by mass. It was noted that many battery powered items are thrown away only after the battery cells have been removed by the last user. A simple evaluation of the manual dismantling process applied to these small, lightweight items showed that the direct cost per tonne for dismantling far exceeds the material value of the WEEE stream. However it is clear that there is sufficient potential revenue to be derived from well-separated material output streams to justify an efficient bulk treatment method yielding high quality, well-liberated materials. Local authorities who are considering a similar kerbside collection of small WEEE are encouraged to carefully select the collection frequency. In this trial it was felt that a three or six monthly frequency of collection would work best and that well-advertised, fixed dates should be used in order to maximize the collection volumes. It was concluded from this trial, that while the mass per household collected during the period was small (at 0.14kg per household), the collection method has potential to ‘rescue’ a large number of small items from the domestic ‘black-bin’ waste stream. If collected as part of a community collection scheme there is potential for re-use of many items which have been disposed of due to a lack of need by the last-user, rather than due to reaching the end of their functional life.


ContentsIntroduction and Background .............................................................................................................. 5 1.0 Trial Objectives ........................................................................................................................ 6 2.0 Methodology ............................................................................................................................ 6

2.1 Collection and categorisation................................................................................................7 2.2 Dismantling into material fractions........................................................................................9 2.3 Detailed analysis of plastics and battery fraction ..................................................................13

3.0 Summary of Catalogued Items .............................................................................................. 14 4.0 Results of Dismantling Exercise............................................................................................. 16

4.1 Total mass of WEEE collected, analysed by category. ...........................................................16 4.2 Material composition of the dismantled WEEE sample...........................................................17 4.3 Material composition of each WEEE category .......................................................................19 4.4 Total battery mass ............................................................................................................23 3.5 Identification of plastics components by polymer type and additive content...................................23 3.6 Average WEEE arising per household ..................................................................................27

5.0 Economic Evaluation of the Output Process and Separated Streams .................................... 28 5.1 Evaluation of dismantling costs...........................................................................................28 5.2 Statistical evaluation of errors ............................................................................................29

6.0 Conclusions ............................................................................................................................ 30 7.0 Recommendations.................................................................................................................. 30 Appendix 1 - WEEE Component Data Sheet ...............................................................................................31 Appendix 2 – Summary of Battery Collection by Chemistry from G&P Batteries Ltd ........................................32 Appendix 3 – Material Composition by Category .........................................................................................33 Appendix 4 – Polymer type and Bromine measurements by WEEE Category..................................................34 Appendix 5 – Copy of Letter sent to All Households in the Trial Area ............................................................37 Appendix 6 – Key to Polymer Type Abbreviations .......................................................................................39


Introduction and Background The WEEE Regulations were implemented across the UK in July 2007 and have now been operational for over one year. The early reports on the mix of collected WEEE items suggest that the increase in the volume of small household electrical items entering the separated waste stream has not been as large as was previously predicted, with most of the collected tonnage centred round large domestic appliances, such as fridges and TV monitors. The 2006 EU Battery Directive came into force across Europe on the 26 September 2008. This places new responsibilities on the waste collection and processing sector to remove potentially hazardous end-of-life batteries from all electrical and electronic waste. This trial was organised by WRAP against this legislative background, in order to:

gather information about the volume and mix of electrical items which arise from a kerbside collection scheme; and

to analyse the number and type of batteries associated with domestic waste electrical equipment. The collection took place in Bury St Edmunds, Suffolk in a region which already demonstrates a very strong recycling performance across other separated kerbside materials. The trial ran for a nine week period from April to June 2008 and covered 20,000 households. Axion Consulting were contracted by WRAP to sort the collected items, transport them to a dismantling centre and to analyse the separated materials. Batteries were removed from the whole sample and sent onto G&P Batteries Ltd for further analysis.


1.0 Trial Objectives The objectives stated by WRAP were to collect data regarding the material composition and itemisation of the waste electrical and electronic equipment (WEEE) generated by the Bury St Edmunds collection trial. Specific aims were to determine:

the total mass of WEEE items collected;

the material composition of a representative fraction of dismantled items;

the total mass in each of the 10 WEEE categories;

the material composition within each of these categories, such as metal, circuit boards, plastics, cable,

batteries, glass etc.;

the total battery mass in the dismantled sample and the whole collection;

the mass of non-WEEE material;

identification of plastics by type and flame retardant content;

the average arising per household in the trial, in terms of number and mass of items;

the potential values/gate fees of the separated streams and, based on the measured quantities, estimate of the net value of a collected and processed small WEEE stream.

This list of objectives was used by Axion Consulting to design and structure the dismantling and analysis process. 2.0 Methodology The trial was conducted in three stages, as shown in Figure 1:

1. collection and categorisation; 2. dismantling into material fractions; 3. detailed analysis of the plastics and battery fraction.

The first stage was conducted in Bury St Edmunds at a local waste recycling depot. The second stage took place at Bruce Metals Ltd in Sheffield. The analysis of the plastics was carried out by Axion Polymers in their Salford laboratory and the batteries were sent onto G&P Batteries Ltd for further evaluation.

Figure 1 – Flow chart showing the stages of the trial

Mixed WEEE collection

Categorisation

Metal Circuit board Wiring Batteries

Dismantling and Compositional Analysis

Plastics

Further analysis by Axion Polymers

Further analysis by G&P Batteries

Ltd

Recycled by Bruce Metals Ltd

Stage 1 - Sorting

Stage 2 - Dismantling

Stage 3 - Analysis


2.3 Collection and categorisation Waste electrical and electronic equipment (WEEE) was collected from the Bury St Edmunds area (20,000 houses, 44,000 residents) over the period from 7 April to 6 June 2008, a period of nine weeks. Bury St Edmunds is well known for its high rate of recycling (50% of domestic waste in 2006) and could therefore be expected to produce a high participation rate by its residents. The collection returned 2,101 individual items in total, which were then stored in two skips (Image 1).1 Residents were advised of the trial and encouraged to take part by means of a letter delivered to each individual household. A copy of the letter is included in Appendix 5. The letter also included a clear list of the electrical items that WOULD be accepted via the kerbside collection method, and gave instructions on how to dispose of larger WEEE items and those specifically not wanted for reasons of potential hazard (e.g. deep-fat fryers).

1 Collection information from Dan Sage, St Edmundsbury Council

____________________________ Image 1 - The first skip of collected WEEE from the Bury St Edmunds area

___________________________ Image 2 – The pallet cages and bulk bags ready for transport to Bruce Metals Ltd, Sheffield


These items were then sorted according to the numbered WEEE categories, as follows: Category Description

1 Large household appliances 2 Small household appliances 3 IT and telecommunications equipment 4 Consumer equipment 5 Lighting equipment 6 Electrical and electronic tools 7 Toys, leisure and sports equipment 8 Medical devices 9 Monitoring and control instruments 10 Automatic dispensers Miscellaneous wiring

In addition to the 10 WEEE categories, a category labelled miscellaneous wiring was used due to:

a) the large amount of tangled wiring found in the skip; and b) not being able to associate items such as chargers, extension cables, kettle bases and power leads

to individual items or categories.

During the sorting phase, it became apparent that the cables connected to items were inhibiting the process due to the tangled mass that they created. These large bundles of wires were separated and then placed into the miscellaneous wiring bulk-bag. The miscellaneous wiring category also contained a few small items which were too entangled to separately remove. Sorted items were placed in 12 pallet cages, with the excess items being placed into five bulk bags. One bulk bag was used for the non-WEEE material found in the collection skips (Images 2 and 3). The pallet cages and bulk bags were then labelled by category and then transported to Bruce Metals Ltd in Sheffield for dismantling and the detailed component analysis. Many of the items collected were in good (and possibly working) condition. However there was considerable contamination from grease, oil, and dirt that added to the difficulty, and potential safety risk, of the sorting phase. There were also several sharp items, including hacksaw blades, electric carving knives and many food-blender blades. The safe handling of these items needs to be taken into account when sorting through a pile of collected WEEE in this manner. This also indicates how the ‘throw it in the skip’ approach to waste collection tends to make downstream re-use of any working or repairable items much more difficult to achieve.

______________________________ Image 3 – Axion employee retrieving items from a skip for sorting


There were several items of note collected including five electric blankets, a chainsaw (disposed of on site owing to safety concerns), a deep fat fryer (again disposed of on site) and two laptops (collected with screens intact). There were also four televisions collected (one pocket TV and three miniature black and white portable versions). Other items collected included ceramic pots, a non-electric children’s mobile and many presentation/storage boxes for shavers. The whole sample was catalogued and packed ready for dispatch to the dismantling site in Sheffield by a licensed waste carrier.

2.3 Dismantling into material fractions The pallets of collected items were shipped to Bruce Metals Ltd in Sheffield for manual dismantling of a representative sample of items into their main material components. Bruce Metals Ltd was chosen on the basis of Axion’s previous experience of working with them on similar WEEE trials. They have the necessary trained staff and facilities to carry out the detailed separation exercise and also have the required waste licensing needed to dispose of the residual materials at the end of the trial. From the total of 2,101 collected items, a sample of 300 was selected for detailed analysis (approximately 14% of the total items collected). These were then manually dismantled to determine their material content. The selection of the items to be dismantled was based upon a ranking of all the items by the frequency of each item type. For the most common items in the sample (kettles, irons and phones) it was decided to aim for 10 of each item as the number to be dismantled. This is based upon the assumption that the majority of electrical items are very similar in design and thus do not display a great variation in material make-up across different manufacturers’ brands. There is therefore little additional data to be gained by dismantling more than this. This approach, of selecting a sub-set from each different item type, was applied across the whole sample set, until down to the single or double occurring items. In this ‘tail-end’ of the sample it was decided to pick a random selection of items across the range for detailed analysis. Table 1 shows this frequency ranking and compares the target sample number with those that were actually dismantled within the limitations of time and resources to do the work.


Table 1 – Items with a frequency greater than 10, showing sample size and actual number dismantled


The dismantling was performed by two employees of Bruce Metals Ltd, under the supervision of project engineers from Axion Recycling Ltd (Images 4, 5 and 6).

Each item was stripped down to its individual components and the separated parts were placed in a plastic container ready for weighing and data recording on a numbered record sheet (Appendix 1). In this way each item

Image 4 - Bruce Metals employees dismantling items for compositional analysis

Image 5 - Axion employee recording the mass of an item on a WEEE component data sheet.

Image 6 – separated metal components from dismantled items.


was given a unique reference number and the data was collected in an organised manner. After the trial was complete, it was also possible to sum up the weights of the individual component splits and to compare the total with the mass of the whole item. This acted as a data-check of the weighing exercise to ensure that no component weights had been missed during the process. An example of this for the toaster in Image 7 is shown in Table 2. This highlights a discrepancy, possibly incurred as a result of the accuracy limitations of the scales used, as discussed in Section 5.2, Statistical evaluation of errors.

Table 2 – Component breakdown for toaster shown in Image 7

_______________________________________ Image 7 – Dismantled toaster


2.3 Detailed analysis of plastics and battery fraction The dismantled components were then separated by material type and sorted into either bulk-bins or individual sample bags. Materials sorted into bulk-bins:

metal – to be recycled as mixed, light-iron scrap; power cable and internal wiring; and printed circuit boards – for low-grade copper recovery.

Material collected in sample bags for further analysis:

plastic components; and batteries – sorted by type and category.

The plastic components were placed in bags and labelled with the item reference number. These were then transported to Axion Polymers’ laboratory for analysis of plastic type and flame retardant content. Batteries from the dismantled items were collected in labelled sample bags and held by Bruce Metals Ltd. At WRAP’s request it was decided to inspect every item from the original collection for any possible battery content. This was carried out by Bruce Metals Ltd in the days following the detailed dismantling process. Once all the batteries had been removed and properly segregated, the complete battery sample was boxed up and made ready for collection by G&P Batteries Ltd. Once the entire bulk sample had been checked for batteries, the remaining items were disposed of via Bruce Metals Ltd’s normal recycling process.


3.0 Summary of Catalogued Items Table 3 below shows the number of items counted and sorted into each of the WEEE categories during the on site sorting exercise. This is broken down by percentages in Figure 2. In total 2,101 items were counted form the collection skips. Not surprisingly, the majority of these items fell into the three WEEE categories associated with smaller household electronic items – categories 2, 3 and 4. Table 3 – Number of items in each category from the collection in Bury St Edmunds

No. Category Number collected % of total

1 Large household appliances 0 0 2 Small household appliances 826 39 3 IT and telecommunications equipment 568 27 4 Consumer equipment 362 17 5 Lighting equipment 92 4 6 Electrical and electronic tools 68 3 7 Toys, leisure and sports equipment 42 2 8 Medical devices 1 0 9 Monitoring and control instruments 25 1

10 Automatic dispensers 0 0 Miscellaneous wiring 117 6

Total 2,101 100

Figure 2 – Percentage of items by category of the total collection

Table 4 below summarises the total mass of material collected in the trial. This is split into the mass of items which were actually dismantled (approximately 350kg) and the remaining mass of items left in the sorted pallet cages. In total the collected WEEE items weighed 2.8 tonnes. The dismantled items listed in this table were

IT and telecommunications equipment, 27%

Small household appliances, 39%

Consumer equipment, 17%

Electrical tools, 3%

Lighting equipment, 4%

Miscellaneous wiring, 5%Toys, leisure and sports equipment, 2%

Medical devices, 0.05%

Monitoring and control Instruments, 1%


weighed at a weigh station accurate to 5kg, giving an indicative weight for these items. A more accurate figure is given in Table 5, where the weights were obtained using a laboratory quality top-pan balance accurate to ±0.1g. The statistical evaluation of errors is discussed further in Section 5.2. Table 4 – Total mass of WEEE by category of the entire collection from Bury St Edmunds

WEEE Category of pallets as labelled Mass of items NOT

dismantled (kg) including weight of the pallet

Mass of dismantled Items (kg)

2 799 134 3 632 61 4 663 122

5 (including monitoring and Medical devices) 234 9 6 Including Toys 314 21

Misc Wiring (including kettle bases) 296 2 Non WEEE 110 0

Total 3,048 350

Total Mass: 3,398kg

MINUS Weight of Pallets: 590kg

TOTAL WEIGHT OF WEEE COLLECTED: 2,808kg


4.0 Results of Dismantling Exercise

4.3 Total mass of WEEE collected, analysed by category. During the trial period, a total of 300 items were dismantled and the component weights recorded on data sheets. These weights were obtained using a laboratory quality top-pan balance accurate to ±0.1g, giving a more accurate figure than that shown in Table 4. The majority of the items were from categories 2 and 3 (small household appliances and IT and telecommunications equipment) - a total of 186 items or 62% of the dismantled sample. Table 5 below shows distribution of the dismantled sample by weight and the number of items in each category. The pie chart in Figure 3 shows the percentage distribution by number of items across the categories.

Table 5 - showing mass of WEEE by category

No. Category Number of items

Weight (kg)

Percentage number of

items 1 Large household appliances 0 0 0% 2 Small household appliances 111 126.69 37% 3 IT and telecommunications equipment 75 67.16 25% 4 Consumer equipment 66 120.11 22% 5 Lighting equipment 15 7.66 5% 6 Electrical and electronic tools 8 13.03 3% 7 Toys, leisure and sports equipment 10 8.43 3% 8 Medical devices 1 0.22 0% 9 Monitoring and control instruments 7 2.72 2%

10 Automatic dispensers 0 0 0% Miscellaneous wiring 7 1.78 2%

Total 300 347.80 100%

Figure 3 - pie chart showing the percentage number of items per WEEE category from the analysed items (note that categories 1 and 10 (large household appliances and automatic dispensers) are not represented on this chart because none were collected)

Percentage of Analysed Items per Category

25.0%, IT/Telecomms

2.3%, Monitoring Devices

2.3%, Misc Wiring

37.0%, S. Household

22.0%, Consumer Equipment

5.0%, Lighting Equipment

0.3%, Medical Devices

3.3%, Toys, Leisure and Sports Equipment

2.7%, Electrical Tools


When compared with the distribution of the full collected sample of 2,101 items shown in Table 3 and Figure 2, it is clear that the smaller sample of 300 items shows a representative spread of items across categories. Statistical check of the sample weights The items selected for dismantling were each weighed accurately and this enabled a representative average weight to be estimated for each of the most common electrical items. For example, 11 kettles were dismantled, the average mass of which was 785g. This average weight of a kettle was then multiplied by the total number of kettles collected (248), to give a projected mass of 195kg of kettles collected: 785g x 248 items = 195 kg of kettles.

This was repeated for all items and the estimated average mass of all the collected items was then used to make a statistical projection of the total mass of all the collected items. This exercise yields a projected total mass of 2,431kg for the full sample of 2,101 items, giving an average mass of approximately 1.2kg for each small household item. This calculation excluded miscellaneous wiring, kettle bases and non-WEEE items. This statistically projected mass was then compared with the weighed mass of the whole sample as follows: Net Mass of WEEE items delivered to Bruce Metals 2,808kg (from Table 4) Projected mass of total sample from individual weights 2,431kg Weight of the mixed wiring and kettle bases and non-WEEE items 406kg Total projected mass (2,431 + 406) 2,837kg Difference (2,837 – 2,808) 29kg These figures indicate that the chosen sampling method gave a result which was representative of the total mass of material. The total mass projected by the statistical extrapolation from the smaller sample comes out very close to the actual mass of the parent distribution (within 1%).

4.3 Material composition of the dismantled WEEE sample Each of the 300 items was dismantled and its material composition was recorded on a ‘WEEE Dismantling Component Data Sheet’ (See Appendix 1). The individual data sets were then combined to give an overall split of material types across the sample as shown in Table 6 below. The discrepancy between the total of 347.8kg shown in Table 5 and the total of 348.3kg shown here represents an experimental error of less than 0.15%.

Table 6 – Table showing total mass of WEEE analysed by material type

Material Total mass (kg) from data sheets Percentage of total material

Light metal/ferrous 167.1 48 Wiring 21.4 6.1

Printed circuit board 28.3 8.1 Plastics 109.9 31.5 Batteries 2.5 0.7

Liquid crystal displays 0.9 0.3 Glass 2.8 0.8

Other components 15.4 4.4 Total Mass of WEEE

analysed 348.3 100

Metal parts are the largest mass at nearly half of the total with plastics accounting for a further third of the input mass. The percentage composition of materials from the analysed items is shown in Figure 4.


Figure 4 – Percentage composition of materials from analysed items across all WEEE categories collected.

% Mass of Component Materials across all categories

Metal48%

Plastic32%

Wiring6%

PCBs8%

Batteries1%

Glass1%

LCDs0% Other (inc. Wood

+ Fabric)4%

Metal

Plastic

Wiring

PCBs

Batteries

Glass

LCDs

Other (inc. Wood + Fabric)


4.3 Material composition of each WEEE category

The pie charts below show the mass of material types by WEEE category. The data has been taken from the table in Appendix 3 which was compiled from the individual item data sheets. ______________________________________________________________________________ Figures 5 – 13 Showing the material composition by percentage in each category.

% Mass Category 2 Small Household Appliances

Printed Circuit Boards

1%

Light Metal / Ferrous

54%

Wire9%

Batteries1%

Plastics34%

Glass0%

Liquid Crystal Displays

0% Other1% Light Metal / Ferrous

Wire


Batteries

Plastics

Glass


Other

% Mass Category 3 IT/Telecoms

Wire4%


14%

Batteries0%


32%

Plastics44%

Glass3%


0%

Other3%


Wire


Batteries

Plastics

Glass


Other


% Mass Category 4 Consumer Equipment

Wire3%


13%

Batteries0%


53%

Plastics21%

Glass0%


0%

Other10%


Wire


Batteries

Plastics

Glass


Other

% Mass Category 5Lighting

Batteries8%

Glass5%

Wood4% Light Metal /

Ferrous36%

Wire11%


3%

Plastics33%


Wire


Batteries

Plastics

Glass

Wood


% Mass Category 6Electric Tools


0%

Batteries0%

Other0%


60%Wire12%

Plastics28%


Wire


Batteries

Plastics

Other

% Mass Category 7Toys and Sports Equipment

Fabric0% Light Metal /

Ferrous19%

Wire2%


14%

Batteries0%

Plastics65%


Wire


Batteries

Plastics

Fabric


% Mass Category 8 Medical Devices

Wire1%

Batteries0%

Other0%


31%


22%

Plastics46%


Wire


Batteries

Plastics

Other

% Mass Category 9 Monitoring and Control Devices

Wire1%


9%

Other0%

Plastics57%


33%

Batteries0%


Wire


Batteries

Plastics

Other


4.3 Total battery mass Table 7 below shows the mass of batteries by WEEE category. During the dismantling exercise at Bruce Metals Ltd, batteries were collected by hand from the 300 items that were analysed in detail. These were weighed and noted on the item’s data sheet. It was observed that a large number of battery powered items are only discarded once the last user has removed the batteries from the item, possibly so they could be re-used in another unit. Staff from Bruce Metals Ltd then went through the whole of the rest of the sample (1,801 items) looking for batteries and sorting them by category. The total weight of the batteries from each category is shown in Table 7.

Table 7 – Table showing total battery mass by WEEE category.

Dismantled sample Remaining items from original

collection (1,801 items)

Total for full collection (2,101

items)

Category

No of items

containing batteries

Mass batteries

(kg)

Mass batteries

(kg)

Total mass

batteries (kg) %

2 ‐ Small household 17 1.30 57% 4.10 59% 5.40 58% 3 ‐ IT/ telecoms 11 0.20 9% 1.00 14% 1.20 13% 4 ‐ Consumer equipment 6 0.30 13% 1.36 20% 1.66 18% 5 ‐ Lighting 1 0.50 22% 0.10 1% 0.60 6% 7 ‐ Tools 0 0.00 0% 0.40 6% 0.40 4%

Totals 35 2.30 100% 6.96 100% 9.26 100%

The total mass of batteries was then collected by special transport for shipping to G&P Batteries Ltd for analysis. The results of the classification of batteries by type is shown in Appendix 2. It should be noted that the scales used to make these measurements at G&P Batteries Ltd were only accurate to 0.5kg. However the following broad split can be seen:

around one third of the batteries are nickel cadmium power packs; just under one quarter are nickel metal hydride battery type; just over one quarter are lithium ion type cells; and lithium thionyl chloride batteries account for most of the remainder of batteries, as total button cell

weight was trivial.

The weigh system used was not able to detect the small button cell batteries collected in the trial, as the total mass was less than 0.5kg of this battery type. 3.5 Identification of plastics components by polymer type and additive content The samples of plastics which had been separated from each item were delivered to Axion Polymers’ laboratory in Salford where further analysis of plastic type was carried out using a Fourier Transform Infrared (FTIR) micro-spectroscopy instrument (Images 8 and 9). Presence of flame retardant additives was inferred by bromine content as assessed using an X-Ray Fluorescence (XRF) analyser (Image 10). From the 300 dismantled items, 100 were chosen as a representative sample and then analysed for plastic type and flame retardant content. In total, 216 plastic components were analysed by this method, from the 100 dismantled items selected for testing.


____________________________________________ The majority of electrical items had several different types of plastic in the separated components. In some cases, plastic type could be identified visually by using the in-mould plastic identification code (PID code). However, in several samples it was found that the stamped PID code did not match with the polymer type indicated by the infra-red analysis. This has been noted in earlier studies and shows that sometimes third-party moulders of plastic components switch polymer type without always informing the end-user of the change or making a mould modification to alter the PID code. The infra-red analyser works by making a comparison of the collected spectra of absorbed infra-red light across a range of wavelengths with a large library of stored ‘known samples’. In this manner the unit is able to offer the best-fit of the measured unknown sample’s spectra to the stored library. Often the machine can return several results for the degree of fit between the sample spectra and those stored in the library. In this case each degree of fit is quoted as a percentage to indicate how closely the unknown sample matches with the library spectrum. Only high percentages (above circa 70% fit) are used to give a positive identification of the unknown plastic material. Plastics were analysed for bromine content using the XRF analyser. Bromine is found in many common forms of flame retardant additive and was widely used in the 1980s and 1990s in electrical goods. Some forms of brominated flame retardants (BFRs) have been banned for use in electrical items under the RoHS regulations and the WEEE Directive states in Annex 2 that plastic containing brominated flame retardant should be separately removed and treated.

Image 8 – The FTIR instrument

____________________________ Image 9 – Close up of sample on FTIR instrument


Most of the tested plastic parts contained background levels of between 1 and 50ppm bromine. This very low reading on the instrument falls below the limits of detection for the instrument (LOD = 100ppm for Br) and can thus be considered as ‘background noise’. However, items often had concentrations of 500 – 100,000ppm, indicating additive treatment of the polymer with BFR compounds. Typically BFRs were added at levels of 4% to 9% to deliver the required level of flame protection, with occasional higher levels being used in some applications. Table 8 shows a summary of the number of different polymer types seen in the 216 individual components that made up the 100 items selected for detailed study. This is shown graphically in Figure 14 and the data table on which these figures are based is shown in Appendix 6. It can be seen that the top five polymer types identified in the sample represent over 60% of the number of items, indicating how the selection of plastic materials for different electrical and electronic products often results in the use of the same polymer material. It is also worth noting that the styrenic group of engineering polymers (e.g. HIPS, ABS, SAN etc) represents over half of the number of plastic components identified in this trial.

_________________________________________________________ Image 10 The XRF analyser


Table 8 – Frequency of plastic type across all WEEE categories (Note: a key to the full name of each polymer type is shown in Appendix 6)

Plastic Type Frequency Percentage

ABS 43 20% PP 22 10% PS 27 13% PC 23 11%

SAN 21 10% ACR 14 6% PA 9 4%

DMPS 7 3% PB 6 3%

PCABS 6 3% PEP 6 3% HIPS 5 2% PET 5 2% POM 5 2% PE 4 2%

PVC 4 2% UP 3 1%

ABS+PC 1 0% ABS-HIPS 1 0%

AEC 1 0% FR-ABS 1 0%

PD 1 0% PP-SE 1 0% Total 216 100%

Figure 14 - The frequency of plastic types

Frequency Composition of Plastic Types

05

101520253035404550

AB

S

PP

PS

PC

SA

N

AC

R

PA

DM

PS

PB

PC

AB

S

PE

P

HIP

S

PE

T

PO

M PE

PV

C

UP

AB

S+P

C

AB

S-H

IPS

AE

C

FR-A

BS

PD

PP

-SE

Plastic Type

Num

ber o

f Par

ts

The bromine testing results are summarised in Table 9 below, which only shows a ‘positive’ bromine detection result when the reading on the XRF instrument is above 100 ppm, its limit of detection for bromine.


Table 9 – Total number of items with positive bromine content

Bromine ppm result

Plastic type

Items with positive Bromine content High Low

Average Bromine content ppm

ABS 7 190,440 938 36,038 PET 3 80,860 8,780 46,770 PP 2 703 207 455

SAN 3 10,640 213 4,437 ACR 5 3,313 412 1,515

FR-ABS 1 100,510 100,510 100,510 PS 5 3,255 132 1,336 PC 1 106 106 106

Total 27 This table indicates that, for the type of WEEE items found in a domestic collection scheme, there is not a particularly high incidence of plastic components that have been treated with brominated flame retardants. Only 27 parts from the total 216 tested show a ppm bromine reading of above 100. While there are a few very high bromine levels (e.g. 8, 10 & 19%) the majority of the flame retardant treated plastic parts have a few percent of bromine content detected by the XRF method (Note: 10,000ppm = 1% ). High bromine content was measured in a relatively small proportion of the components, primarily in ABS, acrylic and polystyrene items from categories 2, 3 and 6 (small household appliances, IT and telecommunications equipment and electronic and electrical tools). This is consistent with the use of brominated flame retardants in items in these categories which may be left ‘switched on’ and unattended for some time. The observations in this study of polymer type and distribution of BFR additives across WEEE categories agree well with those made in an earlier study of 1,500 plastic components carried out by Axion Recycling in 2005 in Hampshire2. 3.6 Average WEEE arising per household The collection covered 20,000 houses from the Bury St Edmunds area, however it is unlikely that all of the homes in the trial area actually participated in the collection trial. The average number of items arising and the average mass of WEEE arising per house are estimated below: Average number of items per household Total number of items/number of houses = average arising 2,101 items/20,000 houses = 0.11 items per house Average mass arising per household Total mass/number of houses = average mass of arising 2808kg/20,000 houses = 0.14kg per house As the average mass of the collected items was 1.2kg per item, the approximate number of participating households could be around 1 in 10 properties, or around a 10% rate of participation. However as some households will have put out more than 1 item over the trial period, the actual rate of participation will probably have been lower than this estimated 10% rate.

2 Final Report on the Pilot Phase of the HNRT WEEE Project by Axion Recycling Ltd. The Sorting and Identification of Plastics from WEEE And ‘Closed-Loop’ Recycling of Polymers for Use in New E&E Goods – Feb 2006


5.0 Economic Evaluation of the Output Process and Separated Streams

5.3 Evaluation of dismantling costs Source data regarding potential sales prices of light metal, wiring, low-grade circuit board and plastics came from Axion Polymers, and Bruce Metals Ltd. Both of these companies have considerable experience of trading material from the treatment and processing of WEEE. However, it must be noted that these prices do vary considerably from month to month, and they are thus shown as an indication of average market rates during Q3 2008 in the UK. Table 9 below compares the likely revenues and costs for a manual dismantling operation for small mixed WEEE of the type collected in this trial. It must be stated that this data is estimated from a detailed dismantling of the WEEE items down to fully separated components in order to allow accurate weighing of the sampled products. It is very unlikely that a commercial operation would carry out the split of material to the level of detail that was applied in this experimental situation.

Table 10 – Comparison of likely material revenues to labour costs for this manual dismantling trial based on material values in Q3 2008

INCOME from materials

Material Sales prices (£/t) Mass in sample (kg) Mass % of items Value per

tonne of collected

WEEE Light metal/ ferrous 150 167 51% 76

Wiring 500 21 6% 32 Low Grade Circuit Board 100 29 9% 9

Plastics 50 110 34% 17 328 100% 134

COSTS of dismantling

Operatives Job cost inc overhead(£/hr)

Hours No of operatives Total (£)

General 10 9 2 180 Supervisor 15 2 1 30

Total labour cost / day 210 Days worked on sample= 3 No of days for 1 tonne 9 Labour cost/ tonne 1,921 The cost and revenue table above shows that, based on market date in Q3 2008, while it may be possible to earn an income of circa £134 per tonne from the sale of well segregated material streams derived from high quality manual dismantling, the associated labour cost per tonne required to break-down small domestic items is very high. The analysis indicates that manual dismantling for this type of small domestic WEEE is unlikely to ever be commercially viable, even if one allowed for a doubling of the mass flow rate through the manual dismantling work-benches. As a comparison, an earlier study of manual dismantling on UK collected WEEE gave an estimated direct labour cost of £240 - £375 per tonne3. However this work was done with the full range of WEEE categories and thus included many televisions, vacuum cleaners and lawn-mowers in the sample, having a huge impact upon the mass rate of dismantling during the trial. The alternative disposal route for separately collected WEEE in the UK is bulk treatment at an authorised treatment facility (ATF). Axion’s market research in Q3 2008 indicates that bulk WEEE recyclers in the UK are likely to pay a positive price of around £100 per tonne (less transport charge) for mixed small WEEE of this type.

3 Initial report on Trial Processing of 5 tonnes of Waste Electrical Material -Keith M Freegard AXION RECYCLING LTD For Hampshire Natural Resources Trust – April 2004


This is a substantial saving on landfill cost, which would be the inevitable route for disposal of these small items, had they not been segregated from the residual waste stream by means of this collection trial. Recent changes in material values are noted, as are regional variations in material values. Collection costs will also vary significantly depending on the frequency and scope of collection.

5.3 Statistical evaluation of errors In this trial the main measurements taken were the mass of individual components and larger weights of whole pallets of WEEE items. In the manual dismantling part of the work, one set of weighing scales, accurate to ±0.1g was used. This means that each individual component weight could have an error of 0.1 of a gram. Therefore an item containing five components could have a maximum component mass cumulative error of 0.5g when the collected data was combined on the data sheet. As average item weight is around 1.2kg per item, this represents a percentage error of just 0.04% on the dismantling weight data. The full pallets were weighed at a weigh station accurate to 5kg, this would account for some of the differences seen in the total component mass taken from the component data sheets compared with the masses taken at Bruce Metals Ltd for each of the bulk bins of separated materials, metal, wire and printed circuit boards. Batteries were weighed at G&P Batteries Ltd on scales accurate to 0.5kg, which can be seen from the values given in Appendix 2. Some battery masses were not included. For example button batteries taken from the 300 dismantled items had a total mass of 57g, however this mass was omitted from the G&P Batteries Ltd summary of the battery collection because the mass was too small for their weighing scales to measure. Overall, apart from the battery input weights, the level of error incurred from the instruments used is consistent with the accuracy required in the results tables quoted in the report.


6.0 Conclusions The main conclusions from the WEEE dismantling exercise are as follows:

1. Kerbside collection of small household WEEE may provide a useful basis for diverting a mass of items, which may previously have been placed in the residual waste stream, into a separately collected waste category for onward re-use, recycling or recovery.

2. The act of storing the kerbside collected items in a bulk waste skip effectively prevents any potential for re-use of the items due to contamination, breakage and mixing with other items.

3. In this collection trial, 2,101 items were collected at a total mass of 2,808kg over a nine week period. The average mass of each item was 1.2kg, with the majority coming from categories 2 and 3 (small household appliances and IT and telecommunications equipment).

4. From the 20,000 households included in the trial, this represents a collection of only 140 grams of WEEE per household. However, given the low level of advertising of the trial this was seen to be an encouraging level of collection.

5. The dismantling of a sample of 300 items from the total collected mass showed that about half of the mass is ferrous metal and a third of the mass is plastics.

6. Styrenic polymers were the most common, followed by polyolefins. A relatively small proportion of the plastic components contained brominated flame retardants. However these materials would still have to be separated during re-processing if the bulk composition is to be kept below the generally accepted commercial limit of 0.1% (1000ppm).

7. A simple economic analysis indicates manual dismantling of the small WEEE items is very unlikely to be commercially viable. However the value of the separated material streams derived from bulk processing of mixed small domestic appliances does show that a positive net income is achievable.

7.0 Recommendations The following recommendations are made based upon the findings and observations of the people involved in the trial:

1. Kerbside collection of small WEEE items could be a useful way for local authorities to divert material away from landfill and to boost householders’ awareness of the need to separate end-of-life electrical equipment. However one of the main findings from this trial is that the collection frequency needs to be either quarterly or every six months, if the volume of equipment from each collection round is to be maximized.

2. There is a large potential to boost the re-use of items, based upon the number of products which were seen to be in a working state during this trial. It is felt that working with a local community group to help organise the collection and subsequent testing of the items would be a good way to make this happen.

3. The advertising that is likely to be needed to promote a successful kerbside small WEEE collection at the above frequency is also seen as a good opportunity to promote the separate disposal of larger WEEE items via the local authority collection facilities and thus further increase recycling rates.


Appendix 1 - WEEE Component Data Sheet

WEEE component data sheet Ref No

Operator Name Date Item Description Time WEEE Category Start Manufacturer name Finish

Brand name Tot.

Mins Date of manufr. Estimated age

Mass of Complete ItemWt. kgs.

Component List Material type Wt. kgs.

Hazard? Y/N

1 2 3 4 5 6 7 8 9 10 Batteries Type Number 1 2 3 4 5 6 7 8 Total of Components Mass Separability Index

Easy < 1 - 2 - 3 - 4 - 5 > Hard

Comments


Appendix 2 – Summary of Battery Collection by Chemistry from G&P Batteries Ltd

Collection details Depot name Bruce Metals, March Street, Sheffield, S9 5DQ Date of batteries collection 30/6/08

Was this your first attempt to collect this container(s):

Y

If N, please give details of previous attempts.

Number of containers collected: 1 small box

Gross weight of collection: (kgs)

Batteries data Total weight of batteries collected: (kgs) 11 kgs

Total weight of batteries by chemistry (kgs) Alkaline/Zinc Carbon Nickel Cadmium – Power Packs 3.5 kgs Primary Lithium Nickel Metal Hydride – Packs 2.5 kgs Lithium Ion – Packs 3 kgs Lead Acid Button Batteries Lithium Thionyl Chloride – Cells 2 kgs Any further comments (e.g. condition of containers on collection) 1 man = 0.5 hrs

NOTE:- Axion have verified that the input warehouse weigh-scales at G+P are only for large pallets of material. They are accurate to the nearest 0.5kg only – hence the figures above are in effect rounded to the nearest half kilo. The button battery mass was not included.


Appendix 3 – Material Composition by Category Category 2 Items Category 3 Items

Number of items dismantled: 111 Number of items dismantled: 75Average mass of item: 1,217.21 g Average mass of item: 835.93 g

Material Mass (g) % of Total Mass Material Mass (g) % of Total MassLight Metal / Ferrous 71,189 53 Light Metal / Ferrous 19,588 32Wire 12,367 9 Wire 2,656 4Printed Circuit Boards 1,989 1 Printed Circuit Boards 8,683 14Batteries 1,340 1 Batteries 298 0Plastics 45,406 34 Plastics 26,392 43Glass 34 0 Glass 1,955 3Liquid Crystal Displays 0 0 Liquid Crystal Displays 1 0Other 1,466 1 Other 1,756 3Total (Kg) 134 100 Total (Kg) 61 100

Category 4 Items Category 5 Items

Number of items dismantled: 66 Number of items dismantled: 15 gAverage mass of item: 1,820 g Average mass of item: 511

Material Mass (g) % of Total Mass Material Mass (g) % of Total MassLight Metal / Ferrous 63,901 52 Light Metal / Ferrous 2,678 36Wire 3,877 3 Wire 791 11Printed Circuit Boards 16,004 13 Printed Circuit Boards 240 3Batteries 339 0 Batteries 563 8Plastics 25,712 21 Plastics 2,474 33Glass 478 0 Glass 337 5Liquid Crystal Displays 0 0 Wood 317 4Other 12,174 10 Total (Kg) 7 100Total mass (Kg) 122 100

Category 7 Items

Category 6 Items Number of items dismantled: 10Average mass of item: 843

Number of items dismantled: 7 gAverage mass of item: 1,862 g Material Mass (g) % of Total Mass

Light Metal / Ferrous 1,580 19Material Mass (g) % of Total Mass Wire 192 2Light Metal / Ferrous 7,518 60 Printed Circuit Boards 1,184 14Wire 1,462 12 Batteries 0 0Printed Circuit Boards 6 0 Plastics 5,374 64Batteries 0 0 Fabric 28 0Plastics 3,467 28 Total (Kg) 8 100Other 46 0Total (Kg) 12 100

Category 9 Items

Category 8 Items Number of items dismantled: 7Average mass of item: 243

Number of items dismantled: 1 gAverage mass of item: 218 g Material Mass (g) % of Total Mass

Light Metal / Ferrous 549 33Material Mass (g) % of Total Mass Wire 23 1Light Metal / Ferrous 67 31 Printed Circuit Boards 155 9Wire 3 1 Batteries 3 0Printed Circuit Boards 47 22 Plastics 936 56Batteries 0 0 Other 0 0Plastics 100 46 Total (Kg) 2 100Other 0 0Total (Kg) 0 100

Total component mass of all Categories: 348 Kg


Appendix 4 – Polymer type and Bromine measurements by WEEE Category

Table showing plastic type and Bromine concentration (ppm) by category

Category 2

Plastic type Number of items % of components

by plastic type Av. Bromine Conc. (ppm)

High / Low conc. (ppm)

PET 1 1% 8780 8780 ABS 11 13% 2075 11890 / 2 SAN 12 15% 896 10640 / 2 PD 1 1% 88 88

HIPS 1 1% 61 61 PP 20 24% 57 703 / 2 PA 5 6% 18 53 / 2 PC 9 11% 12 59 / 2

PVC 2 2% 12 12 /11 PC-ABS 2 2% 5 7 / 2

PEP 5 6% 4 8 / 2 PS 3 4% 4 4 / 3 UP 3 4% 3 4 / 3

POM 4 5% 2 3 / 2 PE 1 1% 2 2

ACR 2 2% 2 2 Total 82 100%

Category 3

Plastic type Number of

components % of components

by plastic type Av. Bromine conc. (ppm)


FR-ABS 1 2% 100510 100510 ABS 12 21% 15880 190440 / 2 PS 5 9% 350 1740 / 2

ABS+HIPS 1 2% 114 114 ACR 8 14% 106 415 / 2

PC-ABS 1 2% 48 48 HIPS 3 5% 31 86 / 2 PET 2 3% 10 16 / 3

PP-SE 1 2% 5 5 PB 5 9% 3 5 /2 PA 1 2% 3 3

DMPS 6 10% 3 5 / 2 SAN 5 9% 3 5 / 3 PC 5 9% 3 6 / 0

ABS+PC 1 2% 2 2 PE 1 2% 2 2

Total 58 100%


Category 4



by plastic type Av. Bromine conc (ppm)


PET 1 4% 80860 80860 ACR 3 11% 1480 3313 / 1119 ABS 7 25% 342 2347 / 3 PS 12 43% 320 3255 / 2 PC 3 11% 14 27 / 5

SAN 1 4% 9 9 PE 1 4% 3 3

Total 28 100%

Category 5





SAN 1 5% 2458 2458 ACR 1 5% 2315 2315 PS 3 15% 44 132 / 3 PC 4 20% 14 50 / 2

PEP 1 5% 8 8 POMS 1 5% 4 4 ABS 2 10% 4 4 PET 2 10% 4 6 / 2 PB 2 10% 2 8 / 4 PE 3 15% 1 3 / 2

Total 20 100%

Category 6





PET 1 9% 50670 50670 SAN 1 9% 213 213 PP 2 18% 22 41 / 3

PVC 1 9% 9 9 PEP 1 9% 5 5 PA 3 27% 3 5 / 2 PC 1 9% 2 2

ABS 1 9% 2 2 Total 11 100%

Category 7





ABS 4 400 239 938 / 6 PVC 1 100 4 4 ACR 1 100 2 2 HIPS 1 100 2 2 Total 7 700


Category 8

Plastic type

Number of components

% of components by plastic type

Av. Bromine conc. (ppm)

DMPS 1 50 5 ABS 1 50 2 Total 2 100

Category 9





ABS 2 17 175405 21210 / 14600 PS 4 33 256 1012 / 2 PC 1 8 106 106

PC-ABS 1 8 17 17 Total 8 67


Appendix 5 – Copy of Letter sent to All Households in the Trial Area



Appendix 6 – Key to Polymer Type Abbreviations Key to Polymer Type Names Plastic type Full name ABS Poly(Acrylonitrile Butadiene Styrene) ABS+PC Poly(Acrylonitrile Butadiene Styrene) + Polycarbonate ABS+HIPS Poly(Acrylonitrile Butadiene Styrene) + High Impact Polystyrene ACR acrylic AEC acylon nylate etylene styrene (AES?) DMPS Polydimethylsiloxane FR-ABS Flame retardent - ABS HIPS High impact polystyrene PA Polyacrylate PB Polybutadiene PC Polycarbonate PCABS Polycarbonate + ABS PD Polydimethyl PE Polyethylene PEP Polyethylene Propylene PET Polyethylene Terephthalate POM Polyoxymethylene (Acetal) PP Polypropylene PP-SE Polypropylene + ? PS Polystyrene PVC Polyvinyl Chloride SAN Poly(Styrene Acrylonitrile) UP Unsaturated Polyester (Thermoset)

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Final Report Compositional Analysis of Kerbside Collected ... · Compositional Analysis of Kerbside Collected Small WEEE 6 1.0 Trial Objectives The objectives stated by WRAP were