HAVBRUK2-Stort program for havbruksforskning

The practical trial at Sunndalsøra was planned for 2022. The trial will run until January 2023. A 60-day Atlantic salmon trial using 6 individual RAS unit tanks with 2 different levels of contamination to produce off-flavor production. KTH sent coated bacteria sedimentation plates which were installed in the test tanks. Alborg and Aarhus University had given advice on planning and carrying out the experiment. Stockholm Water Technology visited Sundnalsøra for three days before the experiment. This was done to test and learn the CDI unit. Due to some problems with facility bookings at Sunndalsøra, the trial was postponed until the end of the year. This summer there was a project meeting in Stockholm at KTH Royal Institute of Technology. A student "Ahinav Singh Parmar" from the "Norwegian University of Environmental and Biosciences, (NMBU) is writing his master's thesis in the experimental part of the project. With the exception of a small delay, all scheduled tasks run as scheduled.

Fin fish aquaculture is currently experiencing significant pressure to improve its environmental sustainability to allow it to continue its rapid growth. As a result of these pressures, the industry is increasingly adopting land-based recirculating aquaculture systems (RAS), where water usage is minimised and the risks of release of inbred strains with associated diseases into wild populations is eliminated as are the associated nutrients that cause local environmental problems. Perhaps the biggest barrier to this industry migration to RAS, is the development of off-taste in these systems caused by the accumulation of geosmin and other chemicals to which the human palate is particularly sensitive. These chemicals are produced by microbial communities in biofilms and in the water column. The current solution to this off-taste development is to purge fasting fish for up to 14 days in clean water with associated significant weight and value loss. Traditional antimicrobial techniques to combat the off-taste micro-organisms are unavailable in RAS due to their negative impact on biofilters as well as their toxic effects on the growing fish. This consortium consists of a strong combination of University, RTD and Industrial partners from Denmark, Sweden and Norway with expertise in RAS systems, biofilm development and microbial off-flavour chemical production, as well as nanomaterials and water quality control. The CDI-NANO-RAS project aims at testing novel technologies for the control of off chemicals in RAS as well as purging systems. We hypothesise that the combined use of novel capacitive deionization (CDI) technology and photocatalytic nanotechnological surface coatings can provide an energetically efficient method for the control of off-taste development in RAS as well as in reducing the duration and water usage in pre-harvest purging. The overall aim is to develop cost effective solutions applicable for the modern RAS industry.