The DEamMONification process for nitrogen removal is an energy-saving technology for ammonia removal from high strength wastewater. The process was developed at the University of Innsbruck, Austria.

The DEMON process is a nitrification/deammonification process in which ammonia and nitrite are simultaneously converted to nitrogen gas, without the use of organic carbon. Process control is based on minute variations in pH, resulting in a very simple and stable process operation. This results in significant savings when compared to conventional nitrification-denitrification processes:

• 50 % on energy for nitrification, since only half of the influent ammonia load needs to be nitrified;
• 100 % on carbon source, since ammonia is used as electron donor.

The DEMON process has been installed at 9 full scale installations with 6 more under construction or startup. The DEMON system at Apeldoorn WWTP, the Netherlands, has an ammonia removal capacity of 1500 kg/day.