The Flotofilter performs a two-stage clarification process in one single tank. It combines two perfectly complementary water purification technologies:

  • Dissolved Dir Flotation (DAF) clarification, perfect for removal of a significant amount of suspended solids (SS), but giving a relatively poor degree of clarification in the low concentrations range and
  • double granular media (sand/anthracite) filtration, perfect for achieving excellent filtered water quality, but accepting only low SS loading

Typically the Flotofilter is used in multiple cells in order to provide continuous operation of the plant. Thus, every single cell can be isolated individually for backwashing without significantly overloading the other cells by the additional flow they receive during the backwash of the cell.

KWI Flotofilter

Main advantages:

  • Turbidity less than 0.5 NTU
  • High hydraulic load: 10 m³/(m².h) (filtration)
  • Algae removal efficiency: up to 98 %
  • High sludge concentration: max. 3% of solid content, with low chemical consumption
  • Smaller footprint and less piping & instrumentation than conventional DAF + media filter
  • Suitable for revamping existing WWTPs


Product sheet

KWI DAF in municipal sewage application

Main applications:

  • Drinking water production from surface water is a typical application for Flotofilter technology. During the warm season, these waters might contain a significant amount of algae and organic matter that is particularly difficult to separate by sedimentation. Dissolved air flotation technology gives excellent clarification efficiency before the granular media filtration step.
  • Drinking water production from borehole water might also require a first clarification step before sand filtration to prevent an occasional increase in the turbidity and extend the operation cycle of the sand filters.
  • Tertiary treatment for hard COD and phosphorus removal

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