There is a general tendency amongst salmon farming companies to produce larger and larger smolt (post smolt) in an attempt to enhance production at sea. With increase in sizes from the often 80-120 gram smolt, sizes in the future will be in the 200-500 grams or even larger. This will entail a need for a considerable increase in smolt production capacity and also entail that part of this production will take place in saltwater.
IAA are specialists with regards to waste management in having a department that deals with sludge handling and effluent treatment within the agricultural sector, a sector where the problems are considerable more complex than what is the case for aquaculture. We can provide tailor made solutions.
With stricter and stricter guidelines for effluent discharge but also with water and energy conservation in mind, we apply de-nitrification increasingly as standard in our RAS whereby make-up water requirements are reduced to 50-80 l/kg feed fed or even less.
Guidelines for CO2 in salmon smolt production have also become stricter. With the combination of centralized and de-centralized de-gassing in our RAS concept, water exchange in the tanks can be kept at 1,3 – 2 times per hour, i.e. we don’t need to flush out CO2 to maintain acceptable levels and we can avoid the increase in pumping and extra water treatment capacity otherwise needed with associated extra costs.
Post smolt production in RAS, will for the latter part of their life cycle, take place in saltwater. Saltwater contains naturally occurring high Sulphate concentrations that can/will create problems in RAS that apply stationary filter technology to entrap solids, i.e. those bio filter concepts that rely on back washing. In these situations there is a real risk of Sulphate Reducing Bacteria (SRB) activity. SRB will have ideal conditions in sludge laden environments and will hamper normal bio filter operation and capacity. In worse case sulphite may be formed, which will have growth inhibiting effect on the fish. This can even happen at sulphite concentrations below the analytical detection level. With IAA’s MBBR technology, none of these phenomena will or can take place.
At IAA, we want to be competitive – we strive to supply value. Our RAS designs focus a lot on minimizing costly piping and concrete structures. We also have a new TURN-KEY concept which has been received with great interest from our customers. It is a concept based on a new structure between the customer and IAA. All uncertainties and unnecessary costs in connection with carrying out a project are eliminated. It makes life easier and there are significant savings.
Finally, IAA can provide well thought out service and management packages that ensures full understanding and optimal performance of a RAS.