Method and apparatus for mixing and surface skimming water treatment basins

摘要

A method and apparatus for mixing a body of liquid in a treatment basin and for removing floating matter from the surface of the basin. A propeller type downflow mixer is buoyantly supported on a float in the basin with the inlet side of the mixer below the liquid level and the discharge side of the mixer arranged to direct the pumped liquid downwardly in the basin for mixing material in the basin. A shield is provided on the float overlying the inlet side of the pump to inhibit direct passage of liquid from the area of the basin above the shield and to induce an inflow pattern below the surface of the liquid toward the inlet of the pump. A scum receiving trough is mounted on the float and extends along the outer margin of the float with the upper weir edge adjacent the surface of the liquid in the basin to receive matter floating on the surface of the basin. Material received in the trough is selectively discharged to a receiver outside the basin.