The time has finally come: The selective desalination process is now being tested under real-life conditions at the waterworks of the Oldenburgisch-Ostfriesischer Wasserverband on Langeoog. The project partners from the BMBF-funded innovatION joint project met on Langeoog to launch the pilot plant.

For the practical tests, DEUKUM GmbH and elkoplan staiger GmbH built a pilot plant which can desalinate up to 100 L/h of water. However, this is not a conventional full desalination, but a selective electrochemical partial desalination. The selective desalination can be achieved by modified membranes, which have been developed by the Leibniz Institute of Polymer Research Dresden e.V. and FUMATECH BWT GmbH over the last three years, and adapted process parameters. With the help of selective desalination, brackish water can thus also be used as an alternative resource for drinking water production. In the case of partial desalination on Langeoog, mainly only sodium and chloride are to be removed from the brackish water, leaving calcium and magnesium in the water.    
So far, however, the process has only been tested on a small scale at the Chair of Process Engineering in Hydrosystems at TU Dresden. Hanna Rosentreter is excited to be able to put the pilot plant on Langeoog into operation: "This is the moment for which we have worked hard together as a team over the last few years. Now we can also analyze the long-term behavior. There have been hardly any studies on this so far, but they are crucial for product development."

Since on Langeoog the freshwater lens is surrounded by saline water, the Carl von Ossietzky University Oldenburg is additionally investigating whether the partially desalinated water is also suitable for infiltration for groundwater recharge.           
Following the tests on Langeoog, the pilot plant is to be tested at the Kreisverband für Wasserwirtschaft Nienburg in the future in order to investigate the selective removal of nitrate.