Sidewall-Box Airlift Pump Provides Large Flows for Aeration, C0_2 Stripping, and Water Rotation inLarge Dual-Drain Circular Tanks

摘要

There are many ways to maintain water quality in recirculating aquaculture systems. A sidewall-box airlift pump is a new alternative for large circular dual-drain tanks that is extremely simple, but could also reduce both capital and variable costs ifit can replace more expensive and higher head axial flow or centrifugal pumps and the gas transfer columns that they supply. The sidewall airlift pump is a spin-off idea that came to the lead author after he visited the Danish model trout farms, which use huge airlift channels to move over 50 m3/min (14,000 gal/min) through a single raceway loop. Kaare Michelsen of Danish Aquaculture developed these large airlift pumps to operate at an ainwater ratio of 0.3:1 and produce a total lift of approximately 20 cm by using four airlifts around the d-ended raceway. The Danish approach to large-scale airlift pumps certainly provides the opportunity for large-scale fish farm applications, i.e., potentially much larger applications than the traditional 8-15 cm dia airlift pipes used by some in North America.