Abstract: A compact dissolved-air-flotation (DAF) clarifier treats raw water with suspended solid contaminants first in a flocculator at the center of an annular tank where microscopic air bubbles float flocked contaminants to form a floating sludge layer. The flocculator has a fixed, cylindrical sidewall. A first clarification, calming and degassing occur here. The water then flows radially outwardly into the tank with a straight cylindrical outer wall where further quiet clarification occurs. A third level of clarification occurs in a lower portion of the tank, specifically, within a set of fixed, inclined lamellae, where a final clarification occurs. The bottom wall of the tank has a set of apertures which allow a gravity flow of clarified water through a layer of pressurized gas to an underlying collection compartment. A set of rotating paddles push the sludge layer up a ramp to an opening in an inclined discharge conduit.

Abstract: A compact dissolved-air-flotation (DAF) clarifier and clarification process utilize three zones for clarification which operate in sequence in a single clarifier. Raw water with suspended solids enters a flocculator at the center of an annular tank where microscopic air bubbles introduced to the inflow float flocked contaminants to form a floating sludge layer. A first clarification, calming and degassing occur here. The water then flows radially outwardly into the tank where further quiet clarification occurs. A third level of clarification occurs in a lower portion of the tank, specifically, in a set of plate-like lamellae, radial and conical, which form inclined channels where a final clarification occurs. The bottom wall of the tank has a set of apertures which allow a gravity flow of clarified water through a layer of pressurized gas to an underlying collection compartment.

Abstract: A compact dissolved-air-flotation (DAF) clarifier and clarification process utilize three zones for clarification which operate in sequence in a single clarifier. Raw water with suspended solids enters a flocculator at the center of an annular tank where microscopic air bubbles introduced to the inflow float flocked contaminants to form a floating sludge layer. A first clarification, calming and degassing occur here. The water then flows radially outwardly into the tank where further quiet clarification occurs. A third level of clarification occurs in a lower portion of the tank, specifically, in a set of plate-like lamellae, radial and conical, which form inclined channels where a final clarification occurs. The bottom wall of the tank has a set of apertures which allow a gravity flow of clarified water through a layer of pressurized gas to an underlying collection compartment.

Abstract: Raw feed water is continuously clarified at a large throughput rate in a single, shallow tank using a flotation process carried out simultaneously in multiple sectors of the tank. Raw water feeds into a rotating trough. A fixed manifold system in the trough dispenses pressurized water containing dissolved air to release microscopic air bubbles. A set of headers each radially extend outwardly from the rotating trough. Each header distributes water and bubbles to a sector of the tank with a net zero velocity. A set of rotating extractors each receive clarified water from the bottom of a preceding sector. A set of scoops skim floated sludge from the water in the tank. The sludge is lifted, as by the rotation of the scoop and/or by a pumped conduit, over the rotating trough to a sludge outlet pipe. In one form the scoop has at least two blades each with an eccentrically located, radially extending compartment that receives, lifts, and then dumps the skimmed sludge as the scoop rotates about its axis.

Abstract: Raw feed water is continuously clarified at a large throughput rate in a single, shallow tank using a flotation process carried out simultaneously in multiple sectors of the tank. Raw water feeds into a rotating trough. A fixed manifold system in the trough dispenses pressurized water containing dissolved air to release microscopic air bubbles. A set of headers each radially extend outwardly from the rotating trough. Each header distributes water and bubbles to a sector of the tank with a net zero velocity. A set of rotating extractors each receive clarified water from the bottom of a preceding sector. A set of scoops skim floated sludge from the water in the tank. The sludge is lifted, as by the rotation of the scoop and/or by a pumped conduit, over the rotating trough to a sludge outlet pipe. In one form the scoop has at least two blades each with an eccentrically located, radially extending compartment that receives, lifts, and then dumps the skimmed sludge as the scoop rotates about its axis.

Abstract: A compact water treatment plant has at least one vertical stack of dissolved air flotation (DAF) type clarifiers. Raw water is directed first to a single stage clarifier with a shallow tank. Its output is fed to an underlying two stage clarifier, preferably one with tall, mutually isolated cells, inclined baffles over a filtration medium in each cell, a cell-by-cell backwash capability, and an arrangement for isolating the first filtrate from the clarified water. Preferably, there are two such stacks in side-by-side array to provide a peak-load capacity, redundancy, and extreme compactness. Also preferably, clarified water from the single stage clarifier flows to the two stage clarifier via a bioreactor and an associated DAF clarifier. A source of aeration defines an upper, aerobic zone in the reactor where bacteria act on organic contaminants (COD's and BOD's). Strips of a deep pile, woven textile form a biocarrier. The strips oscillate in the tank.

Abstract: A tank with a generally flat, rectilinear bottom wall receives raw water for clarification by flotation. An array of lamellae define a set of generally vertically oriented channels. Flotation occurs in each channel. The channels are preferably inclined. A pair of endless chains or the like rotate alongside the tank to move a succession of mutually spaced, paddle-like lamellae through the tank. Sliding seals secured to the edge or edges of the lamellae isolate individual channels, or groups of channels, as they move through the tank. The channels lock and move a column of water through the tank with substantially no turbulence.