The event, Sustainable Engineering Solutions for the Water Industry Using Recycled Materials, was held at the Royal Armouries and was attended by more than 100 industry professionals from all over the country.
It was organized by Wakefield-based testing specialists Aqua Enviro and reported on four trials funded by WRAP, three of them in the Yorkshire region.
Delegates heard from Mark Lowe, operations director with Aqua Enviro, who reported on the trials his organization had conducted at four facilities: vegetable processing company JE Hartley, at Thorganby, near York; Yorkshire Water’s sewage treatment works in Malton, North Yorkshire; Croda Chemicals GB in Rawcliffe Bridge, near Goole; and a paper and board mill owned by Georgia Pacific, in Bury, near Manchester.
Lowe said the reports showed that filtration media made from 100 per cent recycled glass was capable of removing suspended solids from effluent more effectively than traditional materials, provided the right size of glass was used. He added that as a manufactured product, it could be tailored to suit specific wastewater and conditions.
Lowe said the tests at the four sites had all shown the most effective material was medium-grade glass. The key to media performance was whether it enabled back washing - the pumping of clean water backwards through the filters, flushing them clean of sludge – to be conducted most efficiently. Fine glass, for example, was impressive at removing solids but its use meant backflushing was required more often than with medium-grade material.
Delegates at the event also heard a keynote address from Andy Dawe, WRAP’s Materials Sector Manager for Glass.
He explained his organization, a Government-funded, not-for-profit agency, existed to create stable and efficient markets for recycled materials and products, and remove barriers to waste minimization, re-use and recycling.
He said: “WRAP is running a campaign to encourage and promote the use of materials made from recycled glass and we’re delighted with the results of the trials which Aqua Enviro has conducted. These remove any doubt that filtration media made from recycled glass are viable commercially and offer performance benefits, compared to traditional materials and there is a good business case for using it.
“Increasing volumes of products made from this material are becoming available, as 2.5 million metric tons of container glass enters the waste stream each year and processing capacity in line with the British Standards Institute PAS 102 specification increases.”
Dawe explained there was now a steadily rising demand for materials made from recycled glass across sectors such as grit blasting, cementitious products, brick and tile fluxing, and sports turf, in addition to filtration.
He said: “Our work is intended to push the UK towards its target under the European Union packaging directive, which says 60 per cent of used glass must be recycled by 2008. It’s likely that in 2005, we will have surpassed the 50 per cent level.”
Other speakers at the event included; Kristian Dietrich of utility firm Yorkshire Water, Graham May of turkey producer Bernard Matthews, Paul Barter from wastewater treatment company Hydro International, Richard Whale of water engineers Atkins and Professor David Butler of Imperial College London.