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Biological recycling of nutrient wastes

Instead of discharging valuable nutrients and biochemicals we should rather save them by recycling.

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Biological recycling and reuse of organic and inorganic compounds for new bioproduction in industrial side streams are often based on natural processes adapted to industrial conditions. Success criteria include knowledge of production biology and technology, harvesting, processing, product and market and regulations. In order to realize the expected growth in salmon farming, challenges related to feed supply and waste discharges must be solved. The supply of harvestable fish stocks is limited and more than half of the nutrients in the feed used in fish farming are currently lost to the environment. Discharges of waste from fish farming are basically both, pollution and loss of resources. Quality and quantity of sludge varies depending on the time of year (biomass in the production unit, feed type and amount of feed), species (salmon, trout, char) and size (juvenile, post-smolt) and sludge handling technology (dry matter from 10 -> 90%). Recycling of valuable proteins and lipids from sludge through so-called secondary bioproduction of marine low-trophic species with potential as feed ingredients can be an important contribution to further growth in Norwegian aquaculture. Production of e.g. microalgae, macroalgae, polychaete worms and sea cucumbers can be an important source of lipids, proteins and minerals and other valuable resources such as bioactive components, antioxidants and pigments of high commercial value. To develop industrial production of low-trophic species as new marine raw materials, new knowledge is needed about the species' life cycle, production technologies and processing methods that take care of valuable components. SINETF actively works on biological and technological solutions to better utilize waste streams and convert them into valuable products. We have laboratories to produce marine plants and animals on side streams, and we have the necessary laboratories to analyze and process the biomass.