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Tue, 05 February, 2019

Your carpet waste – our feedstock for polypropylene production

The ISOPREP project builds on the achievements of an Innovate UK project entitled ‘High Performance Polymers (HiPerPol),’ which developed a method for solvent based recycling of end-of-life polypropylene (PP) into virgin quality PP that was demonstrated at laboratory scale.  The aim of ISOPREP is to develop this process at pilot scale.  Although applicable to a wide range of PP waste products, our chosen post-consumer product to demonstrate the ISOPREP recycling process is waste carpet.

Carpet is the most popular floor covering used in both commercial and domestic properties in the UK and a notable source of PP waste.  In fact, the fibres of household carpet are thought to contain up to 50% PP, making it a perfect choice as our feedstock.

In the UK alone, around 400,000 tonnes of waste carpet is generated per year, with 56% of this directly ending up in landfills.  As carpet takes around 20 – 30 years to completely decompose, it poses an environmental hazard being left in landfills.  Of the waste carpet diverted away from landfill, currently only 42,000 tonnes are reused or recycled and used in equestrian surfaces and animal bedding.  The majority of waste carpet not recycled or diverted to landfill is used as solid recovered fuel (SRF) which is a high-yield source of energy for producing heat and electricity.  Although it is a good source of energy, burning SRF releases CO2 into the atmosphere, adding to greenhouse gas emissions and disregards the value of waste carpet as a PP resource.  In addition, using waste carpet as SRF necessitates further consumption of limited fossil fuel resources to replenish the PP supply chain.

TWI is set to be the home of the ISOPREP pilot plant and in preparation has already received the feedstock – a whopping 1 tonne of waste carpet.  The waste carpet was sourced by project partners Axion Recycling Ltd. - via a UK carpet recycler - from a UK household waste recycling centre. 

Keep up to date with all ISOPREP news and project updates by following us on our twitter account @ISOPREPproject.