In May of next year, an Anammox® system will be opened in the Dokhaven waste water purification plant of ZHEW in Rotterdam. Through the combination of the Anammox® process with de existing nitrogen removal plant (SHARON - process), a high level of sustainable and economical nitrogen removal from the rejection water of the sludge digestion plant will be achieved.
The Anammox® process was developed in the 1990s by the Delft University of Technology. Paques, that specialises in the development and manufacture of biological water purification systems, then developed the process for commercial purposes. ZHEW, that was involved in the development of the process from a very early stage, saw the economic and environmental benefits of the process, and decided to commission the first industrial application of the Anammox® process.
Brocadia Anammoxians
The Anammox® process is based on the short-circuiting of the nitrogen cycle: ammonium and nitrite are converted directly into harmless nitrogen gas. The bacteria used to trigger this process, Brocadia Anammoxidans, occurs naturally in ammonium-rich environments.
The process creates a saving of about 70% in aeration energy and works entirely without chemicals. Both the operational costs and the CO2 emissions are ten times lower compared with conventional nitrification/denitrification processes. Moreover, the system only requires half the space.
As well as applications in municipal waste water treatment, the Anammox® process is also very interesting for the treatment of all types of waste water with a relatively high nitrogen level and a low organic density, occurring in the (petro)chemical, food, fertiliser, and manure processing industries.
There is already international interest in the process; not only in Europe, but also in Japan and Australia. (Source: Paques / May, 2002)
Fore more information: Cost-effective ammonia removal for waste water treatment
