Development of a Contact Filter for the Removal of Fine Particulates from Recirculating Aquaculture Facilities

Summary:
Solids removal is an essential process in any recirculating aquaculture system. Failure to remove the solids, which are generated from fish wastes, uneaten feed, and bio-floc, incurs negative effects on fish health through both direct and indirect means. The purpose of this study was to determine if a new type of filter, termed the contact filter, will provide the desired effect of fine particulate removal with relatively low impact on current system processes. The device in question is essentially a depth filter employing an extremely porous bio-carrier media as its packed bed. The advantage of such a device is that it has a relatively low pressure drop removing the need for additional pumping costs. The filter is also designed to be self cleaning removing the need for additional work loads, or labour costs. Initial tests performed on the contact filter indicate that the filter is effective at the removal of fine particulates. Overall solids capture efficiencies as high as 51% have been measured across the filter. The pressure drop across the filter is approximately 440 Pa after cleaning, and rises to about 540 Pa after 36 hours of operation without cleaning. Recommendations are proposed in the final report to improve the clean cycle of the filter. The increased efficiency of solids removal allows operators of RAS to reduce even further their dependency on new make-up water.

Project Lead: Kelly Cove Salmon

Total Project Cost: $92,750
           
DFO-AIMAP Contribution: $50,000

Other Financial Support:

• Recipient: Kelly Cove Salmon/ Cooke Aquaculture Inc.
• University of New Brunswick, UNB

For more information please contact the regional coordinator.

Maritimes Region: Cindy.Webster@dfo-mpo.gc.ca