Berson supplied two InLine 250+ medium pressure UV systems, each disinfecting up to 100 m3/hour of backwash water. They are positioned after the ultra filtration units and before the sand filtration. Up to 5% of the produced drinking water at the Spannenburg plant (1.25 million m3/year) is used to backwash the sand filters. The installation of the UV systems enables this water to be reused as drinking water rather than being discarded.

An important feature of the Berson UV technology installed at Spannenburg is its UV-Tronic+ V5 PLC controller, the latest version of Berson’s UV-Tronic controller range. Based on a rugged industrial PLC and with an RS485-based ModBus interface, the UV-Tronic+ V5 links to the site’s SCADA control system and allows users to set up and manage the UV system’s operating parameters to exactly match their requirements.

Peter Sjoerdsma, Viten process engineer, said: “A year since it was commissioned the Berson UV systems are working very well and are completely reliable. The reused backwash water is completely biologically reliable and we are totally confident to use it as drinking water. We opted for UV as it is a clean technology that does not require the use of chemicals. Berson’s UV technology is already widely used by Vitens so we have good experience of their systems.”

The Spannenburg drinking water plant is operated by Vitens. Because the installation has been so successful Berson has now also been awarded the contract for an identical application in Zwolle, also operated by Vitens.