A quick search on the internet about carpet lifespan will heave up any number of self-help sites, telling the average carpet consumer to start afresh every 5-10 years. This advice, along with the never-ending cycle of commercial rebranding, has contributed to the piles of abandoned carpets that now make up at least two per cent of yearly landfill waste.

Carpet waste going to landfill is estimated to be at 400,000 tonnes each year, and this comparatively small figure (compare it to the 7.2 million tonnes of food and drink waste households alone throw out each year, for example) means carpet is considered a niche waste stream. Yet despite this, the organisation Carpet Recycling UK (CRUK) has made it its mission to reduce carpet as landfill waste. The organisation’s target is to divert 25 per cent of carpet waste from landfill by 2015, and figures so far are certainly encouraging: the amount of carpet waste diverted from landfill has risen from two per cent at the birth of the organisation in 2008 to 10 per cent in 2010 and 16.5 per cent in 2011.

There are three main options for carpet waste diverted from landfill, which currently stands at 66,000 tonnes per annum. Jane Gardner, Manager of CRUK, explains that “due to the high calorific value of carpet shreddings, they can be used as a fuel flock replacement in cement kilns”, and so 50 per cent, or roughly 34,000 tonnes, is sent for energy recovery. The remaining 32,000 tonnes are divided between reuse and recycling, options that are both increasingly popular and more environmentally sound.

Carpet tiles are the likeliest candidates for reuse as they are separate units, which facilitate quick sorting and grading. Tiles that are deemed reusable (the majority, as carpet tends to be disposed of for aesthetic reasons rather than due to lack of durability), are then cleaned and sold on to charitable organisations or
low-income households at a lower price than a manufacturer could offer. Gardner notes that the carpet manufacturing industry has seen a move in recent years to develop carpet tiles that don’t require any adhesives, which means that more tiles are of a suitable grade to be reused.

Any tiles that are deemed unsuitable for reuse are sent for energy recovery or to be recycled by carpet reprocessing organisations, along with off-cuts from manufacturers and carpet from specialist collection sites. As a composite material, carpet poses an expensive and difficult problem for recyclers. The complex makeup and the relatively small tonnage mean there have historically been few outlets able to process carpet waste, and so figures have remained low for some time. There are two main varieties of carpet: wool carpets, which come predominantly from households and are made up of wool fibres and latex; and mixed synthetic carpets, which come from more commercial environments and are made up of nylon, polypropylene, latex and chalk. Both varieties also have backing, which has historically been made out of jute or polypropylene. This variety of materials and constituent parts makes the reprocessing of carpets costly.

CRUK is working to help change both the attitude towards carpet and the lack of reprocessors able to manage carpet waste. It has embarked on a series of trials with machine manufacturers and recyclers, with the aim of developing high-value outlets for carpet waste. Previous trials have shown pure polypropylene successfully recovered from carpets at a quality high enough to make products such as buckets and plant pots. Research like this has encouraged more manufacturers and recyclers to focus on carpet as a viable material, and to drive recycling (and reuse) of diverted carpet waste up from 33 per cent in 2010 to 48 per cent in 2011.

To recover the raw materials from the carpet waste, the backing has to be liberated from the fibres, or ‘fluff’; materials are often separated using near infrared sensors (NIRs) that distinguish between fibre types. Carpets with synthetic fibres can then be broken down and reprocessed for use in the construction industry as plastic products such as scaffolding boards and hoarding boards. Synthetic carpet shreddings are also popular for use in equestrian surfaces when mixed with rubber crumb and sand. Woollen fibres, on the other hand, tend to be used in non-woven products such as mattresses, floor underlay and sound insulation. Additionally, these natural fibres are high in nutrients like nitrogen, so can be used for compost and as a soil enhancer.

Creating high-value end products from recycled waste carpet requires contamination levels to be kept as low as possible. Simon Macaulay, Managing Director of Anglo Recycling Technology, a company that handles and processes recycled waste fibres, states that: “The carpets need to be as dry and clean as possible for the materials recovered to be of a high enough standard to be worth the reprocessing cost and energy used.” He adds that as contamination levels come down, higher quality materials can be created from reprocessed carpets.

As the recycling of carpets rises, instances of closed-loop recycling have also begun to appear. The firm Aquafil SPA, based in Northern Italy, has started production of a fibre called Econyl®. Aquafil SPA buys plastic polymer waste products such as discarded fishing nets and nylon carpet fibres already separated from their backing. A chemical process then treats the nylon turning it into caprolactam, which is the basic component of both Nylon 6 and Nylon 66 (the two main plastic polymers used in carpets). Carpet manufacturers then buy back this reprocessed nylon yarn (which Aquafil SPA claims uses 39 per cent less energy than its virgin equivalents) for use in their new products.

Aquafil SPA is currently the only manufacturer in Europe to make a product of this type. There is much interest in the product however: many carpet manufacturers, such as Desso and Interface, are already using the service. At this early stage, the process isn’t fully closed-loop due to the use of plastics from other sources, but it is moving in that direction. Aquafil USA President Franco Rossi recently reaffirmed the carpet industry’s desire for closed-loop recycling when he talked of how Aquafil seeks to “fulfil customers’ needs and stay close to what they want”.

It seems that what with new technological advances being championed by organisations such as CRUK and Aquafil SPA, carpet recycling is becoming more prominent in the industry. There’s still a long way to travel to reach the 25 per cent diversion from landfill target, but here’s hoping the road will be soft and recycled underfoot.