The report is published by the Waste and Resources Action Programme (WRAP) to defend the practice of using recycled glass to make water filtration products.
– Andy Dawe, WRAP
The report, entitled “Environmental Impact Assessment of the Use of Recycled Glass as a Tertiary Filter Medium”, maintains that using recycled glass actually saves money and carbon emissions.
The findings challenge claims made a month ago by financial advisors Grant Thornton that grinding glass “generates more CO2 than if the glass was sent to landfill” (see letsrecycle.com story).
Grant Thornton described the government's policy towards recycling as “carbon blind”, and that energy-intensive processes such as glass grinding produced more emissions than if the glass was just disposed of.
The new study, however, has looked at recycled glass through its whole life cycle in one particular market.
Research carried out by Aqua Enviro at Yorkshire water's Malton sewage plant in 2004 found that recycled glass was found to be up to 10% more effective than traditional sand in the final stage of cleaning commercial and industrial waste water.
The improved efficiency led to a saving on how much power was needed to flush the water through the filter, thereby saving the equivalent of 1,261 kg of carbon dioxide emissions a year.
“Accurate”
Andy Dawe, glass technology manager and support programme coordinator at WRAP, told letsrecycle.com: “We're not decrying the Grant Thornton report, but we have additional information to allow a more accurate assessment of the environmental impact.”
“The improved pumping efficiency reduces CO2 emissions and energy costs. We see this as an extremely important market and an attractive environmental option,” he added.
Mr Dawe said that the carbon saving was four times the level calculated to be the saving from melting glass down.
He explained that in two years the amount of recycled glass used in filtration had already increased by 4,000 tonnes, which was testament to its potential, and that demand would grow with increasingly stringent filtration standards.
The use of recycled glass would also alleviate the need to quarry sand, and therefore deplete natural resources, he added.
Limitations
Despite its positives, however, Mr Dawe did acknowledge some limitations with the use of recycled glass.
The report found that more infrastructure was needed to reduce the environmental impact caused by transporting recycled glass over long distances, which produced more carbon dioxide than transporting sand.
Mr Dawe said: “The logistics would be improved by having new processing centres which would reduce the environmental impact from transport.”
WRAP's glass technology manager also agreed with Grant Thornton that melting down glass again and again for “closed-loop recycling” was still a preferable saying: “We would still consider the priority use of recycled glass as container manufacture as you can use you again and again.”
| Related links: |
Mr Dawe explained that as part of its remit, WRAP was just trying to develop alternative markets. With less demand for green and mixed glass in the UK compared to clear glass, water filtration provides an alternative to landfill.
He said: “We are working to provide an alternative market for glass.”
Register for free to comment