Primaries

Primary treatment serves to remove many of the floatable and settleable solids. In the primary settling tanks, the flow velocity is slowed so the heavier materials will sink to the bottom and the floatable material will move to the surface. Metal bars, known as flights, skim across the surface of the water removing the floating scum before turning downward to scrap away the material that has settled to the bottom. The cleaned water goes to the next process of aeration and the solids are pumped to the gravitational thickener for further processing.

Primary Settling



Primary Clarifiers

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