Plastic: In the bag?

Plastic bags and film have long been a headache for the UK resources industry, as, for many waste processors sorting mixed waste, the film is difficult to separate from other, more valuable two-dimensional waste streams (such as paper), and can easily become trapped in machinery. 

Indeed, according to WRAP’s 2011 report ‘Cleaning and Recycling of Residual Mixed Plastic Film’, for most reprocessors ‘this waste stream is seen as a complication – difficult to collect, even more difficult to sort, with little or no commercial value to be seen at the end of the process’.

Other barriers to the uptake of film recycling include a lack of market for mixed films, which can come in a variety of colours and polymers, though most are made from polyethelyne (PE) or polypropylene (PP). There’s also the fact that many films are contaminated with other streams, such as food waste. 

Due to these barriers, this waste stream has historically gone to landfill, been sent to the Far East for reprocessing (and, in some cases, disposal), or littered – at an estimated cost of £10 million a year in England alone, according to anti-litter campaigning body Keep Britain Tidy.

So, many sighed in relief when the UK’s first facility for reprocessing post-consumer polyethylene bags and packaging films opened in 2013, with Energy Secretary Ed Davey saying the facility’s ‘pioneering technology means local authorities and businesses [would] no longer have to export, landfill or incinerate their waste plastic bags’ when he visited the plant in May 2014 (pictured, centre, between PlasRecycle Chief Executive Duncan Grierson and Chairman Paul Levett).

Built by PlasRecycle with £10.7 million of finance from investors (including the Foresight Environmental Fund, the London Waste and Recycling Board (LWARB) and WRAP), the Woolwich-based plant opened in 2013 with the promise of annually processing 20,000 tonnes of plastic film into a ‘clean’ plastic granulate for manufacturing new black sacks and carrier bags.

PlasRecycle has spent the last four years developing the top-secret ‘high-tech’ proprietary process that can convert ‘what has historically been regarded as a waste material into a useful product’.

The process involves a plethora of steps, but the three main processes are: size reduction and removal of contaminants; washing (as otherwise the resultant product would be too odorous and not fit for much use); and melt filter extrusion and pelletisation.

This article was taken from Issue 78

But it’s not been smooth sailing, Chief Executive of PlasRecycle, Duncan Grierson, tells Resource: “The plant was designed to process around 20,000 tonnes per annum of infeed. However, we are still making changes to the plant, which is not yet able to process at that level. 

“We started running the plant in September 2013 and have had an absolutely torrid time over the last year! But we can see light at the end of the tunnel. With further changes over the next few months we hope to get to the specified tonnage.” He adds that the biggest issue to date has been dealing with contamination, which typically comprises “paper, card, rigid plastics, cans, glass, crisp packets and others”. 

As such, the plant is not yet producing a material that can be used in closed-loop recycling. “We are currently selling the plastic pellet that we produce to manufacturers of damp-proof membrane and other thick film applications”, Grierson explained, adding, “but we hope to improve quality over time to go back into thin film applications such as bags.”

With England’s plastic bag levy coming into effect in ‘autumn 2015’, it’s hoped that the blight of plastic film litter (and its detrimental effects) will be curbed. In the meantime, eyes will remain on PlasRecycle to see if it can deliver the sustainable solution that the UK so desperately needs.