Nitrogen removal for stricter demands - Sweden Water Research

Nitrogen removal for stricter demands

New environmental permits for wastewater treatment plants tend to demand lower effluent concentrations than before.

A VA SYD PROJECT In addition to total nitrogen, very low levels of ammonia nitrogen may be required for new environmental permits, especially when the recipient is a small water body. Such levels can be challenging to achieve based on how the treatment plants are presently designed. This is partly due to that in situations with very high flows, the wastewater is normally bypassed by the biological treatment.

In this project, we investigate how a far-reaching nitrification for low ammonium levels (<0.5 mg/L as yearly average) can be achieved with a compact biofilm pro-cess. The design of a biofilm process is optimized to achieve post-nitrification (after a conventionally designed main biological process) and at the same time treat all wastewater even at peak flow situations.

The project is in part financed by Sweden Water Research.

The project has also received funding of approximately 2.5 MSEK from Interreg South Baltic (www.southbaltic.eu) via the project “ISMA – Innovative solutions for sewage sludge management in small wastewater treatment plants” where VA SYD together with partners around the southern Baltic Sea develop environ-mentally friendly technology for small sewage treatment plants. The objective of ISMA is to reduce the discharge of pollutants from wastewater and sludge into the environment, to test innovative green technologies and develop best practices. Cross-border cooperation with universities and other water utilities will be an important part. ISMA is coordinated by Rybno Commune (Poland) and other partners are University of Warmia and Mazury in Olsztyn (Poland), Lithuanian Research Center for Agriculture and Forest (Lithuania), BEOF – Bornholm Energie og Forsyning (Denmark), VA SYD and Klaipėda University (Lithuania).

  • To develop knowledge about how the process should be designed and operated
  • To determine the appropriate load, volume, operating mode and control strategies