The operators are also making significant savings on water replacement. The Hanovia ultraviolet disinfection systems were installed by Davey Water Products on behalf of Franklin District Council and Community Leisure Management in the town of Pukekohe, south of Auckland.
“Our main purpose for installing the systems was to control chloramines, which are responsible for the distinctive, and at times overwhelming, ‘chlorine’ smell associated with indoor chlorinated pools,” said Franklin District Council’s Property Manager Gwyn De Arth. “Chloramines cause sore eyes and irritated skin and create a very corrosive environment for pool equipment – they are in fact a major cause of rust within indoor pool complexes. Since the system was installed people have really noticed the difference and many visitors have commented on the dramatically improved environment,” he continued.
“Although we still need to add some chlorine for residual disinfection, the amount is much reduced, and chloramine levels are now consistently below 0.2ppm. We have people returning to the pool who kept away before as they were so badly affected by the chloramines. One boy from a local primary school couldn’t take part in swimming classes because of a chlorine allergy, now he happily takes part with no reaction,” added Gwyn.
In addition, a member of a local swimming group called ‘Accessible Aquatics’ had to stop attending as he was having a skin reaction to chlorine. “He’s come back and is really enjoying it,” added one of the group’s volunteers, Elaine Brown. “In fact, everyone in the group has nothing but good things to say about the benefits of the ultraviolet disinfection system,” she said.
The impacts of the ultraviolet disinfection system have been felt beyond the immediate issue of swimmer comfort. Since the switch to ultraviolet disinfection there has been a huge reduction in the amount of dilution water required. “Previously, we had to dump the pool water every week – this has now been reduced to just once a month. When you take into account the increase in visitors we are now getting, combined with the reduction in costs for water, lost energy and chemicals, the savings have been considerable,” concluded Gwyn.
The ultraviolet disinfectionunits installed at Franklin Pool are Hanovia medium pressure PSP UV systems, one of which can each treat up to 200 m3/hour, the other 100 m3/hour, based on a UV dose of 60 mJ/cm2. Automatic wipers keep the quartz sleeves housing the ultraviolet lamps clean, so the only regular maintenance required is changing the lamps every twelve months – a simple operation that is carried out by on-site staff. In addition, Hanovia ultraviolet disinfection systems are compact and can usually be installed within existing pipework, making installation a straightforward process.
Based in the United Kingdom, Hanovia 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. For more information please visit the company's website at www.hanovia.com . Hanovia is a subsidiary company of Halma p.l.c. (www.halma.com) and is represented in Australia by Fluidquip Australia (Pty) Ltd. (www.fluidquip.com.au).