Patent ID: 6015497
Filing Date: 2000-01-18
Classification: C02F,Y02W

Abstract:
A system for the filtration of water used for cultivating aquatic animals, comprising:(a) an aqua-culture tank containing a level of water therein;(b) a filtration tank elongated vertically which has a top at a height above the level of water in the aqua-culture tank, a bottom, a horizontal cross-section and a screen having openings, which said screen spans said horizontal cross-section of said filtration tank below said top and at a height above the level of water in the aqua-culture tank;(c) a bed of buoyant filter media comprised of particles which are larger than the openings in said screen, said bed having a top and a bottom disposed below said screen;(d) a filtration tank influent line fluidly connecting said aqua-culture tank to a point in said filtration tank which is below the bed of buoyant filter media;(e) a circulation pump disposed in said filtration tank influent line;(f) a gas supply line connected to a point in said filtration tank which is below the bed of buoyant filter media; and(g) a filtration tank effluent line fluidly connecting a point in said filtration tank above said screen to said aqua-culture tank;whereby, when water is being pumped upwardly through said filtration tank said buoyant filter media is constrained by said screen, but when water is not being pumped a water level in said filtration tank equalizes with said water level in said aqua-culture tank, thereby permitting said buoyant filter media to float loosely in said water for ease of agitation.