Sanitaire ICEAS SBR Process

The advanced Sanitaire ICEAS process is a fully-automated and simple-to-operate biological treatment system:

  • Operates on a time-based control system allowing continuous inflow of wastewater during all phases of the cycle.
  • Uniquely suited to flow and load variations.
  • Achieves processes of biological oxidation, nitrification, denitrification, phosphorus removal and liquid/solids separation continuously in a single basin.
  • Expands easily and produces high quality effluent.
  • Provides two treatment zones (pre-react and main-react) separated by a non-hydrostatic baffle wall, which deflects flow and creates a quiescent main react zone during settle and decant.
  • Utilizes the pre-react zone as a biological selector for enhancing the growth of desirable organisms.
  • Offers flexibility for meeting specific application needs with engineered process cycles.
  • Proven robust over the last 35 years with over 800 installations worldwide.


The three phases common to all ICEAS process cycles:

  1. 1) React
  2. 2) Settle
  3. 3) Decant


During the react phase, raw wastewater flows into the pre-react zone continuously to react with the mixed liquor suspended solids. Depending on the treatment objectives, the react phase will have periods of aeration, anoxic mixing, anaerobic conditions, or a combination thereof. As the basin continues to fill, biological oxidation/reduction reactions take place simultaneously to treat the wastewater.


During the settle phase, basin agitation from the react phase (aeration and/or mixing) is stopped to allow the solids to settle to the bottom of the basin. Raw wastewater continues to flow into the pre-react zone as the main-react zone settles. As the solids settle, a clear layer of water will remain on top of the basin.


During the decant phase, the decanter rotates downward to draw off the clear, treated water for discharge to the effluent line. Raw wastewater continues to flow into the pre-react zone during the decant phase. Sludge is typically wasted from the basin during this phase of the cycle.