Advances in Pretreatment and Clarification Technologies

The ever-evolving water treatment market continues to improve treatment technologies. Pretreatment using coagulation, flocculation, and sedimentation is being replaced by newer treatment technologies providing enhanced water quality; improved sustainability; smaller footprints; reduced chemical usage; and reduced environmental impacts.

Compared to conventional sedimentation, inclined plates more effectively remove solids with a smaller footprint.

Dissolved air flotation (DAF) removes solids through floatation using micro-bubbles. They effectively remove coagulated turbidity and total organic carbon, algae, and some taste and odor compounds.

Sludge blanket clarifiers and solids contact clarifiers combine flocculation and sedimentation resulting in reduced footprints. Flocculated solids within the unit enhance flocculation through interparticle collisions.

Ballasted flocculation provides high-rate clarification by fixing flocs to a ballast resulting in footprints 5–15% that of conventional treatment and rapid start-up times.

Adsorption using ion exchange and PAC often augment coagulation and clarification by suspending the media in the bulk flow through mixing.