A large scale closed vessel UV disinfection plant from Dutch UV specialist Berson is treating drinking water for around 650,000 people in Paris, France. Located to the north of the city in the suburb of Méry-sur-Oise, the UV plant is one of the largest European installations of Berson’s InLine range of UV equipment. Five InLine 1500 units are installed in parallel to provide disinfected drinking water at the rate of 7500 m3/h.
Berson, a Halma company, is now supplying its medium pressure UV disinfection systems in the UK for the first time. Although new to the UK market, Berson’s UV technology for municipal water and wastewater applications is well established on the European continent, the USA and Australia. The company has many successful reference sites, of which Méry-sur-Oise is just one.
The Méry-sur-Oise plant uses water from the nearby River Oise. Following pre-treatment and nanofiltration the water is pumped through five UV units positioned in parallel, which kills any remaining microorganisms. The treated drinking water is supplied to 37 districts in the northern suburbs of Paris, with daily production totalling 340,000 m3.
The InLine units feature Berson’s innovative MultiWave medium pressure UV lamps, which are orientated perpendicular to the water flow to achieve optimum UV exposure. Unlike conventional UV lamps, MultiWave lamps produce a broad spectrum of wavelengths which act on the whole micro-organism, rather than its DNA alone, ensuring permanent deactivation.
An integral sensor monitors UV light intensity in each treatment chamber, while a custom-built control panel provides communication between the UV units and the plant control room. Also incorporated in each UV unit is an automatic wiping mechanism which cleans the quartz sleeves surrounding the lamps and keeps them free of water-borne deposits.