Recovery and recycling options for white goods

About 75% of the 400,000 tonnes of domestic appliances discarded in the UK each year are processed by fragmentisers and a proportion of this, mainly metal, is recycled, according to a Warren Spring Laboratory (WSL) study.1 Design to ease dismantling could boost the recycling and refurbishment rate. WSL also recommends a funding mechanism to pay for CFC removal from insulation foam.

A draft German law currently under consideration would oblige dealers to accept or collect used appliances for recycling. Once the law is adopted, pressure is expected for similar measures to be extended throughout the EC on harmonisation grounds.

In the UK, the Government is encouraging the reuse and recycling of materials, while the Advisory Committee on Business and the Environment has recommended that the amount of metal disposed of to landfill should be minimised. Pollutants contained in some white goods, such as PCBs and CFCs, have already come under legislative pressure.

It is this background which prompted the Department of Trade and Industry to commission a report from WSL on the recycling of discarded electrical appliances. The study analyses arisings of white goods scrap, reviews current recycling and refurbishment options, and discusses how PCBs, CFCs and the increasing plastics content could affect recovery operations.

The table below shows the UK's annual arisings of white goods scrap. Some 37% of the tonnage is accounted for by washing machines, although these only represent 20% of the number of appliances scrapped.

Of the total, 260,000 tonnes consists of metal and 45,000 of plastic. Washing machines, cookers and refrigeration equipment account for 75% of the metal arisings, while plastics come mainly from fridges and freezers and vacuum cleaners (see table ). The large proportion of "other" materials from washing machines is due to the concrete balance weights used to steady the spinning drum.

On recycling, the report concludes that fragmentisers are an ideal option for processing items with a high metal content. Indeed, 315,000 tonnes of white goods, 75% of the total, are processed through fragmentisers.However, with the reject fraction at 38% for fridges, 25% for washing machines and 13% for cookers, the actual amount recycled is much lower.

Fragmentisers are probably not the best option for items with higher plastics contents, WSL believes, unless the residue is incinerated with energy recovery rather than landfilled.

Dismantling may be one option for these appliances and may be used to increase revenue at civic amenity sites through the sale of recovered items. However, WSL found that it may not be cost-effective for some goods.

For washing machines, it was relatively easy to remove the main motor, but further dismantling to recover the stainless steel inner drum was "unlikely to become economic" due to difficulties in separating the main bearing from the inner drum.

To dismantle a cooker, over 40 screws had to be undone to remove the heating elements. But for fridges and freezers the compressor units were easy to remove and markets exist for the dismantled product. The same was true of the transformer in microwaves, but it took 15 minutes to gain access.

The most promising dismantling operation to recover plastics is for vacuum cleaners. One manufacturer is conducting trials to recover the ABS. However, the process is currently uneconomic because of the low price of virgin ABS.

One of the drawbacks to dismantling has been poor design. Only now have manufacturers begun to mark plastics and reduce the number of sizes and types of screws used. WSL recommends that fewer types of plastics should be used and that unlike plastics should not be bonded together. Fillers and additives that do not cause problems for recycling should be used. In addition, modular construction would ease the task of removing different sections of the product.

There is some promise in refurbishment of white goods. Some washing machines disposed of at civic amenity sites are being sold for refurbishment. However, the reject rate is over 90%. Refurbishment is uncommon for cookers and refrigerators and is likely to remain so - partly because spare parts are difficult to obtain for ageing machines.

WSL's study found that the PCB content of white goods is declining because of legislation introduced in the last two decades. No PCBs are likely to be found in items disposed of after 2000, the report concludes.

CFCs pose a problem in the disposal of refrigeration equipment although there is currently no UK legislation requiring CFC recovery from refrigerators, unlike the USA, the Netherlands and some other countries. The present CFC recovery rate was recently estimated at 20% (ENDS Report 219, p 14 ).

Commercial equipment is available for the removal of CFCs contained in insulation foam. However, at a cost of o15-20 per refrigerator, WSL says that a funding mechanism would be needed to make a treatment scheme viable.

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