Innovative removal of N, P and organic matter in effluents from recirculating aquaculture system

Coordinator: Per Bovbjerg Pedersen, National Institute of Aquatic Resources, Technical University of Denmark
Total budget: EUR 1 million
Duration: 2,5 years, 1.4.2017-30.9.2019

Summaries of annual reports:

Recirculating aquaculture systems (RAS) provide technology for sustainable fish production in nutrient-sensitive areas such as Baltic Sea. Although RAS implies reduced discharge, most of the nitrogen (as nitrate) and some of the phosphorous and organic matter are, however, still found in the outlet of the production unit. Additional removal in terms of cost-efficient end-of-pipe treatment is therefore needed to reduce final discharge and comply with environmental conditions and regulations in the Baltic Sea.
Innovative solutions improving the efficiency and reducing the use of external resources are thus imparative for future development. Therefore, BONUS CLEANAQ seeks to develop novel technologies and procedures for brackish/saline aquaculture systems investigating and optimizing 1) Single-sludge denitrification using fish waste as carbon source 2) Carbon-free denitrification; using woodchip-supported denitrification and/or electrochemical removal 3) Removal of the phosphate load using organic flocculants.
To optimize the techniques, state-of-art stable isotope and molecular methods will be used for the analysis of microbial processes to support mass balance calculations in fish production using experimental and full-scale RAS. The technologies developed and applied through the project will support the design and application of resource-efficient technologies, ultimately allowing RAS to decouple fish production from environmental impact in the Baltic region.

Keywords: recirculation, end-of-pipe treatment, microbial processes, denitrification, P-removal

Partners: Denmark, Finland, Sweden

For more information visit the BONUS CLEANAQ's website and the BONUS projects' website.