The effluent of anaerobic reactors such as the UASB and the AnMBR contains nitrogen in two main forms: ammonium (NH4) and ammonia (NH3). To remove and recover the nitrogen from the effluent, ammonium stripping can be applied.

In this process, ammonium is first converted to ammonia, which is then stripped with air. Once the ammonia is in gas form it can be absorbed in a solution, for instance with sulphuric acid to obtain ammonium sulphate. This end product can be used to replace artificial fertilisers.

The use of ammonium stripping to obtain ammonium sulphate is applied in demosite Helsingborg.

For more information please download the factsheet.