UK: glass sand to be used to filter water

Glass packaging waste could be about to revolutionize the water industry in the UK. Until now, specially quarried high grade white sand has been used to filter drinking water and remove bacteria and i…

Glass packaging waste could be about to revolutionize the water industry in the UK. Until now, specially quarried high grade white sand has been used to filter drinking water and remove bacteria and impurities. However a Scottish company has found a way to make a suitable artificial “sand“ by crushing glass bottle waste. The “green sand“ has been successfully tested by water companies and is being used in 50 swimming pools in Scotland to keep the water clean. With a GBP 1 million grant from the European Union and the UK Department for Environment, Food and Rural Affairs (Defra), Dryden Aqua of Bonnyrigg, near Edinburgh is building a factory to crush beverage bottles into a sand-like substance. The idea is not only to reduce quarrying of the scarce sand but also to develop new uses for waste glass. The UK currently uses 5.5 million tonnes of glass a year but recycles only 750,000 tonnes of this amount. The problem is particularly acute for green glass, which constitutes half the waste but is worth only GBP 15 per tonne, compared to GBP 30 per tonne for clear glass. Dryden Aqua scientist and managing director, Howard Dryden, has spent six years working on what he calls Active Filtration Media, or AFM. He admits that he has given what is no more than recycled glass a “fancy name” to remove the stigma of what many would regard as an inferior product. He says he needs beverage bottles for the sand to be sure that drinking water would not be contaminated by non-drinkable liquids. Crushed-down beverage glass looks like green sand but had fewer impurities than the real thing and performed better in trials. The factory has a daily production capacity of 100 tonnes of AFM, although Mr Dryden sees this as a large-scale pilot project rather than full production. He thinks the market will be able to use 250,000 tonnes of green sand a year. The plan is to build five or six factories in cities in the UK where the waste is generated, in order to cut down on transport. The factory will be completed this month and is expected to go into full production on 14 January 2004. Once it is providing a “regular” product, the government“s drinking water inspectorate will be asked to perform tests and approve it for general use by water companies.