BOC’s new SOLVOX® OxyStream technology for land-based aquaculture programmes provides a whole-life option with significant advantages over other systems.
Aquaculture Show UK, Aviemore, Scotland. 23-24 May 2012. BOC are in the Alfresco Marquee, Stand 6.
SOLVOX® OxyStream tackles three critical conditions essential for an effective and efficient aquaculture process: it efficiently dissolves oxygen into the stock tank water, directly at point of use; creates the correct hydrodynamics with adjustable directional flow into the aquatic environment; and strips out potentially harmful gases such as dissolved nitrogen. In addition, the system is easily installed – both in new and retrofit projects – and is virtually maintenance-free.
The technology is particularly suitable for the increasing trend to ongrow fish to post-smolt stage in the same location through to maturity. All through this process the salinity is increased and the SOLVOX® OxyStream will operate over a full range of salinity conditions from fresh to seawater. This avoids any need to transfer fish from land-based tanks to sea cages as they grow.
SOLVOX® OxyStream technology from BOC, a member of The Linde Group, is a combined oxygenation and flow control system, which dissolves the optimal amount of oxygen in the inlet water flow, distributing it evenly at all depths with an adjustable flow pattern through the tank. The fish stock benefit from the physical exercise involved in swimming against the current created evenly in the whole of the tank. The flow regime can be tailored to fish size, stock density and fish species, such as salmon, sea bass or cod. The OxyStream systems are designed and built for each growing tank profile, installed as single units or pairs in each tank, dependant on size. Now water flow and oxygen dosing can be individually controlled for each tank catering for varying biomass, thereby increasing efficiency.
The micro-bubbles created by SOLVOX® OxyStream create the additional benefit of reducing the concentration of dissolved inert gases such as nitrogen or argon. Oversaturation of nitrogen, for example, even in relatively small quantities, can endanger the wellbeing of fish stocks, slowing growth and increasing the possibility of disease and ultimately, increasing mortality. With the installation of SOLVOX® OxyStream, external degassing units to prevent inert gas build-up will often be rendered obsolete.
Depending on the application, pumping pressures as low as 0.05 to 0.2 bar can be sufficient to oxygenate the incoming water, strip nitrogen and create optimal tank hydrodynamics. This low operating pressure makes the system very energy efficient. OxyStream also requires very low maintenance as it is not associated with any ancillary equipment to manage water pressure.
According to BOC Technical Specialist Keith Nicholson, “The move to whole life farming in land-based facilities allows much closer monitoring of the maturation process. Disease can be better controlled and since the fish remain in the same tank, there is a reduced risk of stock loss by reducing transfer between storage units and negating the use of well boats and tankers on transfer to sea cages. However, until recently, maintaining the oxygen levels and quality of the environment in land-based facilities over a sustained period was a difficult challenge. The SOLVOX® OxyStream solution makes this a problem of the past. It means that whole-life on-land aquaculture is now an attractive and cost effective option for the industry.”