Experimental study on transport characteristics of sediment waste products with forced recirculation flows in an aquaculture pond

Atthe shrimp farm in Okinawa prefecture, Japan, recirculation flow was gen erated by operating water wheels in an aquaculture pond to maintain appropriate environ ment for the growth of shrimp. The recirculation flow causes the secondary current of the first kind and can accumulate sediment to the center part of the recirculation. However, when a separation wall was installed in the center of the pond for aquaculture management, mass mortality of shrimp occurred due to disturbance of the recirculation flow. It is considered that the separation wall disturbed the recirculation flow and disabled the accumulation of sediment waste products such as leftovers and feces. This study aims to establish a sediment accumula tion method in square shaped aquaculture pond. We use square shaped pond (3 m x 3 m) as a model of aquaculture pond and polycarbonate pellets (specific gravity 1.17) as a model of waste products. We conduct the laboratory experiment with different pump discharges. The effect of spin-up to the sediment transport is also examined by changing the supply method of sediment.