Aquaculture or aquafarming is the controlled breeding of aquatic, therefore in water, living organisms - in particular fish, mussels, crabs and algae. Aquaculture is gaining importance due particularly to overfishing.
Compared to classic fish production in ponds, only a tenth of the water volume is needed for production in closed loop farms. The low volume of water needed is achieved by cleaning the fish water in a naturally developed biological filter. This allows pure water to return to the circulation system.
The water must be enriched with oxygen (O2) for the breeding of fish in pools that are small compared to natural conditions. This normally occurs through ceramic diffusers, however, these are very susceptible to wear.
The EDUR solution includes a multiphase pump that is able to promote a water-oxygen mixture. Instead of the pump that is needed to maintain the circulation process as it is, an EDUR section-type pump is installed in which pure oxygen (O2) is injected. This oxygen is added in a solution in the water within the multistage pumps and is added to the breeding tank. Through the pressure drop (pressure release) in the tank, the oxygen escapes in fine bubbles and enriches the water with oxygen.
It is also possible to inject the oxygen into the pump after the first stage (impeller) to increase efficiency. The oxygen is compressed higher through the increased pressure at this point and the volume is reduced so that altogether more oxygen can be added to the system.
The combination of highly efficient EDUR multiphase pumps as well as the complete elimination of system components susceptible to wear reduces the costs per liter of added oxygen to an absolute minimum.
Thus, EDUR provides a reasonable solution for aquacultures to reduce operating costs of energy-intensive closed loop farms.