Utvikling og optimalisering av norske rensesystemer for fisketransportvann basert på UV-teknologi for å imøtekomme nye norske krav

The overall idea of the project is to develop and optimize environmentally friendly water treatment technology to reduce the risk of transmission of pathogenic agents during fish transport according to the new Norwegian Transport regulation (FOR-2014-04-11-528). Developing an environmentally friendly technology which combines physical separation (filtration, cavitation etc.) and UV radiation, along with any other disinfection methods, also requires taking into account factors such as the construction of the fishing vessel, crew competence, daily routines for washing and disinfecting equipment / surfaces etc. Implementing such consideration will be needed to meet new and more stringent requirements from the Norwegian authorities and wellboat owners. The latter is dependent on this for continued competitiveness in the Norwegian and international market. The aim of the research work will be determining optimal conditions for design, operation and management of technology for effective removal of the organisms required acc. regulations, while energy consumption is minimized. Data will be generated as far as possible through experiments in laboratory scale, with extensive testing of various parameters and optimization. The first results show that UV irradiation alone is very effective in inactivating the relevant fish pathogens selected for this project; ie. Salmonid alfavirus (SAV) that causes pancreatic disease (PD) and amoebe that causes amoebic gill disease (AGD). However, AGD was very resistant to chlorine and ozone treatment, but not SAV. No synergistic effect could be observed with combination of UV irradiation and chlorine treatment. Subsequently, testing in larger scale tests were conducted to verify these promising results from the laboratory study, with expected fish transport water quality instead of clean water. The results confirmed the laboratory's study results; very good inactivation rate was observed in test water quality representative of fish transport water quality expected duirng well boat transport for same minimum UV dose than applied during the laboratory studies. Approximately 1m3 of test water was used per test with at leas 30 fishes were swimming in there for at least 3 weeks. The challenging water quality of the test water was confirmed by chemical analyzes done at the laboratory. The test was run with and without filter located upstream Then, on a larger scale, testing on NIVA's infection test room was carried out to verify these promising results from the laboratory study in fishing waters, instead of clean water. The results confirmed the laboratory's study results; it was possible to inactivate at least 3 logs of SAV with 25 mJ / cm2 UV dose as a minimum UV dose for approx. 1m3 test water where at least 30 fish have been swimming for at least 3 weeks; ie representative water quality of fishing waters during well boat transport. Challenging water quality for the test water was confirmed by chemical analyzes in the laboratory. The test was run with and without filter located upstream of the UV chamber; no inactivation rate difference could be observed as no live SAV was detected in any of the treated water samples. Approximately the same density of living SAV was observed in control samples collected after pumping but without treatment than in test water collected prior treatment. It was unfortunately not possible to confirm those treatment effect results onboard of a wellboat due to the logistic Challenges when an SAV-outbreak is observed. The project is organized as a partnership between Wellboat Owners association, four equipment/disinfection technology suppliers (Mentum AS, Xylem AS, Moss Hydro AS, Redox AS), 4 laboratories/reerach institutes (Norwegian Institute for Water Research, Norwegian Veterinary Institute, SINTEF and Labora AS) and 3 regulators (Norwegian Maritime Directorat, Norwegian Food Safety authority and DNV-GL).

Forskningsresultatene fra prosjektet bekrefter til myndighetene og næringsindustri at minimum UV-dose påkrevd i det nye PD-regelverket som trer i kraft i 2020 er tilstrekkelig for SAV. De fleste nye bygd brønnbåt har installert om bord et rensesystem basert på UV-teknologi som er miljøvennlig. De opererer UV-teknologi med UV doser som skal være lik eller høyere enn den minimum påkrevd UV dose; i.e. 25 mJ/cm2. Dermed burde være færre og færre PD-utbrudd. Men det registreres allikevel mange PD-utbrudd hvert år ved norske kysten. Dermed gjenstår det å bekrefte at behandlingseffekt om bord i brønnbåt er lik enn observert under dette prosjektet og/eller trengs det mer forsknings for å finne ut andre mulige vektor av SAV enn brønnbåt.

Kombinasjonen av filtrering og ultrafiolett bestråling (UV-bestråling) er vist å være en effektiv metode for desinfeksjon av ulike vanntyper, også for rensing av fisketransportvann på fiskefartøy. En kjemikaliefri rensing av ballastvann har mange fordeler. Det er imidlertid noen problemer som må løses for at norske UV-teknologier skal lykkes på det store norske markedet for behandlingssystemer for fisketransportvann. Den overordnete målsettingen i prosjektet er å videreutvikle og optimalisere renseteknologier for fisketransportvann som kombinerer filtrering, UV-bestråling og andre desinfiseringsmetoder. Dette for å tilfredsstille nye norsk Transportforskrift krav, og derved være konkurransedyktige nasjonalt. Prosjektet er organisert som et samarbeid mellom 5 norske leverandører av renseteknologi for behandling av sjøvann, brønnbåteierforening, en Diagnostic laboratoriet i Nord-Norge og 3 forskningsinstitutter. I tillegg er prosjektet støttet av 4 forskjellige myndighetsrepresentanter, asnvarlig for norsk regelverk. I prosjektet vil det bli gjennomført forsøk i laboratorieskala og i fullskala. Resultat fra forskningen skal bidra til å løse: - Problemene med partikkelfjerning som alle behandlingsteknologier for sjøvann i dag sliter med - Problemer med usikker effekt overfor UV-robuste fiskepatogener - Problemene med manglende analyseverktøy for å bestemme overlevende organismer før og etter UV-behandling - Problemer med usikker effekt og høyt energiforbruk ved fullskala UV-behandling av fisketransportvann FoU-resultatene vil bli benyttet for å komme fram til riktige betingelser for dimensjonering, drift og styring av teknologiene for effektiv fjerning av de organismene som kreves i.h.t. regelverket, samtidig som energiforbruket holdes lavest mulig. Prosjektet vil bidra til økt salg og økte markedsandeler for industripartnerne.