-Combined chlorines fall from 0.9 ppm to just 0.3 ppm-
Since replacing its ozone water treatment system with two Hanovia UV disinfection systems, Alton Towers Resort, the UK’s leading theme park resort, has seen a dramatic fall in combined chlorines in its large indoor leisure pool – from 0.9 ppm to just 0.3 ppm. Combined chlorine levels in its whirl pool are also lower.
Photo: http://www.halmapr.com/hanovia/AltonTowers.jpg (855 KB)
Combined chlorines (or chloramines) are responsible for the distinctive ‘chlorine’ smell associated with indoor chlorinated pools. They also cause sore eyes and irritated skin and are a major cause of rust within indoor pool complexes.
“Prior to installing UV, on a typical busy Saturday with over 3,000 visitors, we’d see combined chlorine levels of around 0.9 ppm in the main pool,” said Waterpark Manager Kevin Carr. “That was a good figure, but since we switched to UV it’s closer to 0.3 ppm – this is an incredibly low value. From the perspective of swimmers and employees the difference means a much better poolside environment, with none of the chlorine smell or sore eyes typically associated with indoor pools. Last summer some of the life guards complained about having sore, red eyes, but that is now a thing of the past.”
Chlorine dosing is still required in UK indoor public pools, even if UV or ozone is used as the primary disinfectant. “We add 1.0 ppm of free chlorine at pH 7.25 and this is sufficient to ensure a high level of residual protection for our visitors,” added Kevin.
The Hanovia UV systems installed at Alton Towers Resort are medium pressure PSP units. The system for the main pool treats up to 1,018 m3/hour; that for the whirl pool treats up to 166 m3/hour, based on a UV dose of 60 mJ/cm2. For both systems automatic wipers keep the quartz sleeves housing the UV lamps clean, so the only regular maintenance required is changing the lamps every twelve months.
Commenting on the installation, Hanovia’s UK Sales and Service Manager Diane White said: “The UV systems were purchased and installed by FT Leisure, the swimming pool water treatment and filtration specialists, who have been very professional and easy to deal with throughout the project. FT Leisure now also has the contract to service the entire pool water treatment system.”
“The fact the Hanovia UV systems are so easy to use is a major advantage,” continued Kevin. Our employees are all busy, so knowing that they can just rely on the systems to work effectively in the background has a tangible value. Someone simply checks the UV systems’ control panels once a day and logs the parameters to record usage and condition.”
The water treatment process for both the main pool and the whirl pool are the same, with 100% of the water passing through six medium sand filters before passing through the UV systems. This is followed by an injection of free chlorine before the water passes back to the pool or whirl pool.
Based in the United Kingdom, with a worldwide distributor network, Hanovia (www.hanovia.com) is a world leader in UV disinfection technology for swimming pool, aquaculture and industrial applications. The company has over 80 years’ experience in the design, development, manufacture and distribution of UV systems worldwide. Hanovia is a subsidiary company of Halma p.l.c. (www.halma.com).
For further news stories from Hanovia and to subscribe to the Hanovia RSS News Feed please visit the Hanovia News Blog at http://halmapr.com/news/hanovia/ .