More than just a bin bag
12 August 2016
It's not easy being green - neither is producing a refuse sack from 100% recycled waste. Catherine Hackett visited one of the UK's largest recycling facilities of polythene waste to find out more about the challenges the industry faces
The urgency to recycle is greater than ever. Oceans will contain more plastic than fish by 2050 unless the world takes radical action to stop rubbish leaking into the seas, according to a recent report from the World Economic Forum.
And yet, while green credentials may influence our purchasing decisions, when it comes to everyday items such as bin liners, price and performance top the list.
The challenge for manufacturers of recycled products is to tick all three boxes. This is no mean feat as the process of recycling highly contaminated waste into second-life products requires significant time and investment, as I discovered during a visit to BPI Recycled Products' manufacturing site in Heanor, Derbyshire, where polythene from agricultural waste is recycled and reprocessed into refuse sacks and bin liners.
The polythene plastic used on farms to protect crops arrives at the site to be washed, cleaned and extruded or ‘re-born’ as Low Density Polyethylene (LDPE) and Linear Low Density Polyethylene (LLDPE) pellets. Traditionally, this material would have been buried, burnt or landfilled. The plastic is initially checked by hand as items can become mixed up in the bale.
"We have found bottle tops, beer cans and even knives and iPhone cases mixed in with the plastic before," refuse operations director Paul Rampling says.
The waste then enters the washing plant – the noisiest area, where machines whir and grind 24 hours a day as they wash off contaminants. Farm waste is one of the trickiest to recycle with up to 60% contamination by soil, sand, and/or stones.
In the recycling area the heat is palpable. It is dominated by an enormous cylinder, which turns out to be one of the largest recycling machines in Europe. It was installed last year as part of BPI's three-year strategy to invest in new processes and technology.
Inside this cylinder, the waste is chopped up, heated and melted into pellets, with any remaining contamination filtered out.
Once the plastic is in pellet form it is ready for manufacture and the extrusion process gets underway. The pellets are melted down into molten polymer, which is dyed and made into sheet format at the desired thickness.
A new extruder is being installed that will speed up production and enable BPI to manufacture multi-layer films, leading to a thinner but stronger product.
Gerry McGarry, business director of BPI Recycled Products, says: "In the past five years, the technology has really started to develop and move forward. The latest technology now uses less energy and can produce a lot faster at a better quality.
"The new machines we have installed are a multi-million pound investment but we either move ahead or be overtaken by the Far East."
Inside the bag conversion hall, a new wrapping unit that is faster and more efficient turns the extruded plastic sheet into a bag. It seals the bottom and creates a perforation at the top for the tie before winding it up into a roll. The bags are now ready to be packed and distributed.
More than green
BPI recycles up to 70,000 tonnes of plastic waste each year, from which it produces 30 million sacks a week, including its Green Sacks. Made from 100% recycled waste, they have a low carbon footprint, having been manufactured in the UK from UK waste. Every tonne of recycled polythene used to make the Green Sacks is said to save 1.8 tonnes of crude oil, reduce energy use by two thirds and entail 90% less water usage compared to a tonne of virgin polythene.
BPI says that every tonne of polythene recycled to make Green Sacks cuts sulphur dioxide emissions by 33% and nitrous oxide emissions by 50%. It also prevents the release of 1.5 tonnes of CO2 into the atmosphere. But while the environmental benefits of recycled products are attractive to consumers, it is essential that they are competitively priced and offer performance benefits.
Gerry McGarry says: "We invest heavily in recycling but there's no point if the actual product isn't fit for purpose. BPI manufactures its Green Sack range from 100% recycled UK farm waste polythene because its linear polymer make-up provides higher tensile strength and impact resistance, which results in a superior quality refuse sack."
This quality is backed up by technical certifications including CHSA (Cleaning & Hygiene Suppliers Association) and UN approval. BPI also recently achieved Zero Waste to Landfill Certification from Valpak at three of its manufacturing sites – Heanor, Rhymney and Stroud.
Gerry adds: "We're not out there to be the cheapest – we innovate and offer a high service level. In our sector it's crucial that the order arrives on time, in the right quantity and at the right price."
Collecting waste and turning it into refuse sacks is a well-established sector – BPI has been doing it for three decades – but it still faces a number of challenges.
Finding waste is as time consuming as making the product. BPI is constantly on the look-out for new areas of scrap and is moving into highly contaminated waste streams to meet supply. Cleaning waste is also an issue.
Gerry explains: "The technology isn't quite there yet – 70% of polythene waste is exported from the UK to China as it's easier to remove the contamination by hand over there."
Despite this, he believes that more could be done to increase UK recycling targets. BPI is involved in initiatives that it hopes will act as a catalyst for change, including partnerships with WRAP (Waste & Resources Action Programme) and The Ellen MacArthur Foundation. Both aim to accelerate the transition to the circular economy – an industrial economy that produces no waste and pollution – by engaging with key stakeholders.
With the UK poised to 'go it alone' as Brexit negotiations get underway, BPI believes that recycling more waste into second-life products could benefit the nation immensely by not only reducing landfill but also conserving resources and creating UK manufacturing jobs.