ASEKOL is a not-for-profit organisation that arranges take-back systems for WEEE on behalf of producers and importers of EEE. Based in Prague, ASEKOL was founded in July 2005 by leading market players in the consumer electronics, telecommunication and IT sectors (including LG, Panasonic, Samsung and Sony).
ASEKOL has built up more than 16,000 WEEE collection points across the Czech Republic including its unique provision of stationary collection containers, which came into play during this CRM recovery trial. (There are around 3,670 units in towns and cities across the country, equating to an average of one collection point per 655 people.)
Linking WEEE collection to CRM Recovery
ASEKOL initially completed a WEEE collection trial to access the materials required to undertake CRM recovery trials. Using a mix of mobile containers, stationary containers and collection yards, ASEKOL ensured that they got as close to the public as possible. Using this range of collection methods ensured that they were able to collect a sufficient amount for the recovery trials. The collection trial results are summarised below:
MEthodology – the recovery Trial process
The aim of the recovery phase of the ASEKOL trial was to develop and test suitable processes to maximise the recovery of target CRMs from the output fractions.
Three fractions with the highest potential for recovery were chosen for developing the methods:
- Precious metals (gold, silver, palladium);
- Rare-earth elements (cerium, dysprosium, holmium, lanthanum, neodymium, praseodymium, samarium); and
ASEKOL competed two treatment trial campaigns; one using WEEE from collection yards and the other using WEEE from stationary and mobile containers. Treatment trials were performed (in partnership with an Enviropol WEEE plant) on a special WEEE treatment line where a number of activities to depollute the WEEE items were performed (including shredding, milling and magnetic separation).
During the treatment trials, some of the WEEE collected was identified as suitable for re-use and did not enter the recovery trial phase. From a total of 22,571 items collected, 694 pieces (3%) were chosen as being potentially suitable for re-use (8.9% by weight). N.B. all of these were in the category of ‘IT and telecommunications equipment’; i.e. personal computers, laptops, tablets, monitors and mobile phones.
Laboratory Recovery Trials
The lab-based trials had a number of objectives, including:
- Extracting the three fractions identified as having the greatest potential for CRM recovery.
- Developing suitable methods for recovery of elements of interest.
A range of techniques and pieces of equipment were used to fulfil these objectives, including:
- Atomic absorption spectroscopy – to determine precious metals.
- Optical emission spectroscopy – to determine copper and rare-earth elements.
In very general terms, the recovery trial found that:
- For light fractions (< 0.5 mm) using screening and wet gravity separation techniques identified material with the highest purity and concentration of precious metals.
- For light fractions (0.71 – 1,5 mm) a combination of milling and electrostatic separation was the best method for recovery of precious metals.
- The concentration of rare-earth elements in the light fractions was very low.
- For fine ferrous fractions, screening was the most effective method for rare-earth element recovery.
- One thing noted during final trial evaluation results, was that it could be assumed that by the time WEEE enters the Czech Republic collection system, it is generally too old and / or damaged to be suitable for re-use.
- WEEE suitable for re-use was very unlikely to be arising in the small domestic appliances (SDA) stream within the Czech Republic trials, compared to other European countries.
- Development of various lab-scale recovery methods needs further work. However, ASEKOL did determine that for some of the fractions, they were able to extract more CRMs and rare-earth elements (although not to a saleable level) within the scope of their trial.
- For plastic fractions, ASEKOL found they are suitable for increasing recovery of CRMs after primary treatment through shredding. Milling and electrostatic separation was the most successful of these methods
- For fine ferrous fractions, hand-picking and / or a combination of baking, milling and sieving was most successful, although not necessarily suitable for upscaling to an industrial application.
Replication of Activities
- Within the scope of this project, a suitable recovery method was not found when using fine ferrous fractions. However, there is an opportunity for further trials to be focused on this material.
- Thanks to the opportunity to test and trial different techniques (and to collaborate with equipment manufacturers), ASEKOL plan to test more separation methods using fine ferrous fractions.
- Within this recovery trial, output fine ferrous fractions from the treatment line contained low concentrations of rare-earth elements suitable for further recovery. This situation may change in the future, however. The composition of this output fraction will evolve with innovations in electronic devices, leading to higher use of rare-earth elements. A lower volume of precious metals is also envisaged.
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