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Developing Bulk WEEE Polymer Separation and Analysis Techniques - WR0202

Axion Recycling proposes to concentrate on Research theme 2 ‘Systems for resource recovery’; Programme area 2.3 ‘Sorting systems, including processing and reprocessing technologies’. Our emphasis will be on the systems and logistics of handling non-MSW plastic wastes from electrical, electronic and similar equipment, the reprocessing of wastes into primary products and secondary products, and integrated systems that handle these and other types of waste.

The expected benefits of the project are proof of practical and commercial viability of sorting and separation systems for waste electrical and electronic equipment (WEEE). The beneficiaries will be the many companies, large and small, in the UK which are currently developing infrastructure and processing systems to cope with the rapid growth in supply of WEEE for recycling in the UK as a result of the WEEE Directive. The work will also benefit organisations that are developing systems to treat polymers and shredder residue from end of life vehicles.

Axion proposes to research systems to maximise recovery of high quality, uncontaminated plastics from WEEE and their subsequent processing to realise maximum environmental and economic gain.

Axion aims to develop separation methods and procedures for full separation of WEEE polymers by polymer type and within each polymer type into those which contain brominated flame retardants (BFRs) and those which do not.
Recycling of WEEE polymers and separate treatment of BFR-containing materials will be essential in future for the UK to ensure compliance with the requirements and targets of the WEEE Directive. DEFRA support will help to ensure that policy targets can be achieved. This research will complement and build upon process development work that a consortium led by Axion is undertaking for WRAP.

There is very little public domain information that we have found anywhere on the performance of alternative bulk separation systems specifically for WEEE polymers.

The project will build on and complement work currently being done by Axion and some of the project partners on a WRAP funded project to develop a process to extract brominated flame retardants (BFRs) from WEEE plastics. The focus of this project is primarily on development of a process to extract BFRs once a polymer containing these materials has been isolated. Initial polymer separation trials are being carried out in the course of the WRAP project. This work has highlighted that there is very little practical knowledge available on how to separate these materials economically.

The WEEE and RoHS Directives require separation of BFR containing polymers when recycling WEEE plastics. This means that separation of polymers by type and into BFR and non-BFR fractions is essential for any WEEE recycling system.

The practical trials proposed for this new research will test and compare techniques for separating different polymer types and also for separating polymers of the same type with and without BFRs. The resulting analysis will be of benefit to all organisations involved in recycling polymers.

The WRAP research has demonstrated that it is very difficult to measure the performance of a polymer separation process by visual means. In most cases the contaminants in a separated sample are white chips, just like the target material. The semi-automatic polymer particle characterisation system that will be developed in the course of the research is novel and will be of enormous benefit for any organisation developing or operating a bulk waste polymer separation process.
Part A

Objective: Develop test methods to characterise real WEEE polymer streams and to measure the performance of WEEE separation processes

Measure & Test the attainment of objective: Wolfson Electrostatics, BIRAL and Axion, working together, will develop a semi-automated system for characterising the type, BFR content and density, piece by piece, of the WEEE polymer streams fed to and resulting from the bulk separation processes.

This system will be used to analyse the feed and product streams to:

· Optimise/improve in the design of the separation processes
· measure and compare the efficiencies of the separation processes that are tested

The design of this system will be based on a small scale manual characterisation trial that is currently being carried out by Axion and Wolfson Electrostatics as part of their WRAP-funded BFR extraction project. This small scale trial has highlighted the need for a semi automated system to provide vital design and performance data for large scale WEEE separation systems.

Part B (To be run concurrently with part A)

Objective: Conduct rigorous experiments to compare a range of alternative bulk separation techniques for WEEE polymers

Measure & Test the attainment of objective: Axion, working with London Metropolitan University and a range of subcontractors and equipment suppliers will conduct practical separation trials using carefully characterised and statistically meaningful samples of real WEEE to test a range of alternative bulk separation techniques for WEEE polymers. Methods will include hydrocyclones, centrifugation with variable density media, jigging, tribo electric separation, optical sorting and possibly froth flotation Separated polymers will be processed to produce final moulded products in collaboration with a major electronic equipment manufacturer

Part C

Objective: Evaluate the separation processes tested in terms of their commercial and technical performance and their environmental impact when operated at full commercial scale

Measure & Test the attainment of objective: Axion will evaluate and compare the separation solutions tested during the project in terms of their technical and commercial performance and will work with a suitable subcontractor to evaluate their environmental impact.
Project Documents
• Final Report : Final Report: Developing bulk WEEE polymer separation and analysis techniques   (4154k)
• Executive Summary : Delivering bulk WEEE polymer separation and analysis techniques   (85k)
Time-Scale and Cost
From: 2005

To: 2007

Cost: £209,000
Contractor / Funded Organisations
Axion Recycling Limited
incl. processing and reprocessing              
Environmental Impact              
Environmental Protection              
Method Development              
Monitoring and evaluation              
Performance measurement and benchmarking              
Sorting systems              
Systems for Resource Recovery              
Techniques & methodolgies for waste management              
Waste collection and handling systems              
Waste Management              
Fields of Study
Waste Management