Moving baffle for improving solids transport and reducing labor costs and phosphorous discharge in aquaculture raceways

Flow-through raceways have velocities below that needed to remove solids from rearing areas and thus require intermittent, manual sweeping to remove the solids producing long solid residence times and exposure to mechanical breakage which results in increased phosphorous leaching and poor fish health. This SBIR proposal offers a novel moving baffle as a new technology to solve these concerns. Preliminary work at WSU has shown that a moving baffle can lead to enhancements in velocities and solids removal. The preliminary work, though, has also shown areas where design improvements are needed. The proposal objectives are aimed at resolving identified barriers and moving the concept towards commercialization. Specific objectives are to: (1) improve the design of the baffle so that it can travel freely as well as address issues with fish movement, crowding, and mechanical breakage addressed by earlier reviews, (2) develop strategies to retrofit the moving baffle to various raceway conditions, and (3) evaluate the performance of the baffle in terms of fish health, water quality parameters, and cleaning effectiveness. Objectives will be accomplished through a team comprised of AEB Engineering, WSU researchers, and Andgar Corporation, an industrial fabricator. A completed prototype of the moving baffle will remove solid waste from the raceways with minimal breakage and phosphorous leaching via the increased flow velocities resulting from the baffles movement under hydraulic head pressure and as a result aid considerably in the management and practices at flow-through commercial fisheries and hatcheries.