Bulk box aerators: Advantages and design
Fisheries Bioengineering Symposium: American Fisheries Society Symposium 10
Colt J;White RJ;
American Fisheries Society
Many of the problems associated with packed-column aerators in salmon hatcheries (splashing, icing, wall flow, channeling, blasting, uneven flow control, fouling, and wasted space) can be reduced or eliminated by using a container with a large surface area (bulk box) for the media, rather than the usual battery of small (300-mm-diameter) columns. The recommended bulk box design includes layers of 25-mm-diameter pall media rings arranged on their sides, a media bed area sized for a hydraulic loading of 1,000-3,000 L/(min/m2), bed depth calculated with a stage efficiency equation, a plate distributor designed according to an orifice flow equation, a stilling box to minimize inflow turbulence, and a modular box structure with louvered sides for ventilation. A bulk box can be used to increase aeration performance (oxygen in, nitrogen out) and decrease the costs of construction and operation of a packed column aeration system.