Water & Wastewater Treatment

WATER TREATMENT As well as drinking water, Dryden says AFM can improve swimming pool quality and human health And the tide may be beginning to turn. A Scottish Water plant in Inverness has been commissioned to study the effectiveness of AFM in improving drinking water. Dr Dryden is so convinced of future demand his company is already planning to build a second plant in Fife next year which will have the capacity to process a further 160,000t/year. Maintaining the supply of recycled glass is a key aspect of the business. The current plant already uses a quarter of all the green bottles used in Scotland. If both plants are operating at full capacity, Dryden Aqua would be able to use every single used green bottle in the country. The AFM produced by both plants would be almost enough to supply every water treatment plant in Europe. Dryden is already in talks with supermarkets, with local authorities and with community organisations on the ground to ensure he can be sure of having enough green bottles to keep the factories running. He hopes to see a scheme where consumers who return green glass to bottle banks can be awarded extra loyalty points and hopes community groups will be able to use money from their recycling efforts to fund local projects. Dryden Aqua is also participating in a major study of water quality in public swimming pools in an attempt to show the need for improved water filtering systems. Dryden is deeply concerned about the lack of water quality standards in UK swimming pools and believes improving water quality and reducing chemical overload in public swimming pools would have major health benefits. As a former marine biologist Dryden is proud that AFM is used in public aquariums around the world - including the Istanbul Aquarium and the Oceanagraphic Museum in Monaco, founded by Jacques Cousteau. The health of fish and aquatic mammals in water cleaned by AFM has reduced the need for chemicals and improved the health of whales and dolphins in captivity. It is one of the reasons he is so convinced of the effectiveness of his product. "I thought - we have improved the health of the dolphins - now let's improve the health of the people." nnn Technology focus: AFM Activated Filter Media (AFM) was developed by Dryden Aqua research to replace sand in all mechanical water treatment applications. AFM is manufactured from a specific type of glass and processed to provide a hydraulicallyoptimised media - in terms of particle-shape and particle-size distribution. The glass then proceeds through an activation process to increase the surface area by 300 times more than ordinary crushed glass or sand. The high surface area is negatively charged (zeta potential) to adsorb organics and small particles. The surface also has permanent metal oxide catalysts that give a high redox potential to make AFM self-sterilising. Green magic - Dryden Aqua's AFM, which comes from re-engineered Howard Dryden says, "AFM is all about removing unwanted glass pathogens and compounds, such as priority substances and phosphate. The permanent surface structure of AFM creates a water membrane that acts like a selective molecular sieve, so we have the ability to focus different types of AFM to remove different chemicals including; ferric, manganese, tributyltin, chromium and arsenic from the water. "Not only does AFM outperform sand and other media types on water quality, but it is also safe and it is saving our clients a small fortune on their operating costs. AFM should also last for 50 years in a drinking water system. In effect it will last for the life of the filtration system." 18 Water & Wastewater Treatment January 2014 wwtonline.co.uk

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