The following summary is based largely on the DEFRA document Guidance on Best Available Treatment Recovery and Recycling Techniques (BATRRT) and treatment of Waste Electrical and Electronic Equipment (WEEE) .
Fluids – these are typically found in heating and cooling appliances, such as fridges and freezers (coolant circuit) and oil-filled radiators. The WEEE Directive requires the removal of all fluids from WEEE. Fluids must be safely removed prior to crushing or shredding operations. Cooling appliances containing refrigerants (fridges and freezers) – most refrigerators reaching the waste stream are between 10 and 15 years old and are therefore likely to contain Ozone Depleting Substances (ODS) (e.g. CFCs and HCFCs). Units manufactured after 1994 are unlikely to contain CFCs.
Fridges and freezers identified as containing ammonia must have their ammonia extracted and transferred to a suitable container pending disposal. As well as presenting a fire and explosion risk, ammonia is potentially hazardous to both the environment and human health.
Capacitors containing polychlorinated biphenyls (PCBs) – Historically PCBs were used extensively in electrical equipment such as capacitors and transformers. However, their use in open applications was widely banned in 1972 and they have not been used in the manufacture of new equipment since 1986. Plants that had been installed prior to 1986 were allowed to continue until the end of their working life. Thus it should be assumed that capacitors manufactured before 1976 contain PCBs. However, unless an appliance is more that 20 years old the chance that it contains capacitors containing PCBs is very remote. All uses of PCBs were to be phased out by the year 2000. For guidance re capacitors containing polychlorinated biphenyls see “Do you know how to work safely with PCBs?
Mercury containing components such as switches or back-lighting
Mercury is used in fluorescent lamps, medical equipment, data transmission, telecommunications and mobile phones. Its use in electrical and electronic equipment has declined significantly in recent years and its use is banned (save certain exempt uses) from 2006. Apart from batteries, most other mercury containing items are likely to be found on a circuit board. Thus removing the circuit board would result in removal of most mercury containing competent such as switches.
Increasing numbers of non-CRT flat panel screens (such as liquid crystal display (LCD), laptop and desk top monitors and plasma screens) are entering the waste stream and requiring specialist treatment. In 2010, an estimated 9 million flat screens were likely to have been sold. Whilst evidence suggests that since the mid-2009 there is a switch to LED back-lit screens this is relatively slow and the use of back-lights containing mercury will continue. It is considered that there will over 145,000 tonnes of flat panel displays in the waste stream by 2016/17. One of the main issues surrounding the treatment and recovery of flat panels at end of life is the presence of mercury containing fluorescent back-lights required in particular to illuminate the LCD, laptop and desk top monitor screens from behind (NB: plasma screens do not present the same hazard). Manufacturers declare an average of 3.5mg of mercury per back-light and the average 37” television can have up to 18 lamps but research suggests this value is often higher. The current main option for treatment is manual disassembly to remove the mercury containing back-lights for specialist treatment and the separation of the remaining material streams. This has high labour costs and potential health and safety implications. For further information see WRAP report on flat panel display recycling technologies .
Toner cartridges, liquid and paste, as well as colour toner – commonly found in printers, fax machines and photocopiers. These should be removed whole and intact so as to prevent the dispersal of toner and then stored in suitable labelled containers.
Asbestos waste and components which contain asbestos – asbestos has been used in older appliances such as electric coffee pots, toasters and irons. Asbestos was also a component of some electric heaters and other items that benefited from the heat resistant properties of the material. Modern appliances are not permitted to contain asbestos; however, operators of treatment facilities need to be vigilant for items which might contain asbestos. Appliances that are over 20 years old might contain asbestos and therefore should be examined carefully and treated accordingly. Detailed risk assessment, training and safe systems of work will be required for handling products likely to contain asbestos. Work should be organised so that materials likely to contain asbestos are identified and work not initiated without adequate controls being taken in accordance with Control of Asbestos at Work Regulations 2006.
Lead and other substances including phosphorous pentachloride in CRTs –lead and other substances hazardous to health such as phosphorous pentacholoride can be liberated during the processing of the glass to remove the fluorescent coating.
Components containing refractory ceramic fibres (RCFs) – mainly used in furnace/heater/kiln linings. Respirable RCFs are classified as category 2 carcinogen. Although RCFs may be used in both domestic appliances and building heating appliances, the insulation material used in domestic electrical appliances are more likely to contain components based on mineral wools rather than RCFs. Appliances which might contain RCFs must be examined to determine if they contain RCFs and appropriate controls put in place before they are removed (see further guidance on RCFs).
Components containing radioactive substances – can be found in a variety of equipment in many commercial settings (e.g. fill level detectors, static eliminators, radium luminised dials, old trim phones) as well as smoke detectors.
Information taken from http://www.hse.gov.uk/waste/waste-electrical.htm