Category Archives: News

Sterner AS introduces NP Drumfilter in Norway

Sterner AS ( is a leading company in water treatment in Norway. Sterner has been working with microscreen filtration since the beginning of the 1990s, with over 900 drumfilters delivered, mainly for the aquaculture business.

The NP Drumfilter is now replacing Sterner’s earlier line of drumfilters, and is being launched in Norway by Sterner’s offices in Ski, Bergen and Leknes.

“Drumfilter technology has not seen any major development in the past 20 years. When Nils-Åke Persson mentioned that he was developing a new drumfilter, we were immediately interested. Our ambition is to be first with new and better solutions,” says the Managing Director of Sterner, Bjarne E. Pettersen.

Nils-Åke Persson’s comeback greeting


During 28 years in the water treatment industry, I founded and built Hydrotech into an industry leading microscreen manufacturer. Together with my partners, we developed the microscreen technology for aquaculture, industrial and municipal applications.

Since selling the original business, I have retained an active interest in filtration and microscreen technology, providing support in recent years to Nordic Water. Following approaches from a number of previous customers I have returned and established a new microscreen company together with my old partners, Rikard Olsson and Anders Mohlin; together, we make up NP Innovation.

Our first release is the NP Drumfilter; a development of our previous designs that have been so successful for more than 20 years. But of course, this is no longer enough, and that’s why we have improved, developed and verified the design in a number of areas. Check it out, and rest assured: there is more to come. You and the industry deserve better. A whole lot better.

Kind regards

Nils-Åke Persson
together with my partners Rikard Olsson and Anders Mohlin