Sequencing Batch Reactor (SBR)

  • Proven and tested methodology  all over the world for the last 7‐8  decades.

    • Several modifications available  for specific requirements.

    • Uninterrupted power supply  required for aeration and sludge  recirculation.

    • Reactor sludge levels to be  carefully monitored and sludge is  to be withdrawn from the system.

    • 80‐90% removal of bacteria.

    • 90‐99% removal of viruses

The Sequencing Batch Reactor (SBR) is an Activated Sludge Process designed to operate under non-steady state conditions. An SBR operates in a true batch mode with aeration and sludge settlement both occurring in the same tank. The major differences between SBR and conventional continuous-flow, activated sludge system is that the SBR tank carries out the functions of equalization aeration and sedimentation in a time sequence rather than in the conventional space sequence of continuous-flow systems. In addition, the SBR system can be designed with the ability to treat a wide range of influent volumes whereas the continuous system is based upon a fixed influent flow rate. Thus, there is a degree of flexibility associated with working in a time rather than in a space sequence.

SBR produce sludge with good settling properties providing the influent wastewater is admitted into the aeration in a controlled manner. Controls range from a simplified float and timer based system with a PLC to a PC based SCADA system with color graphics using either flow proportional aeration or dissolved oxygen controlled aeration to reduce aeration to reduce energy consumption and enhance the selective pressures for BOD, nutrient removal, and control of filaments. An appropriately designed SBR process is a unique combination of equipment and software. Working with automated control reduces the number of operator skill and attention requirement.


  • Better resistance to sludge bulking than other types of activated sludge systems.

  • No need for external clarifiers.

  • No need for external clarifiers.

  • Greater system flexibility and control than other types of activated sludge systems.

  • Less land required and less processing equipment to maintain than other types of activated sludge systems.

  • Greater ability to meet effluent limitations (organic and nutrient) than other types of activated sludge waste/ Wastewater treatment systems.

  • Can retrofit existing tanks, basins, and ponds.


  • Low maintenance and user friendly design.

  • Eliminates all diffusers and associated network costs.

  • Eliminates all diffusers and associated network costs.

  • Easy to integrate nitrification/ denitrification cycles and to facilitate biological phosphorus removal.

  • Eliminates the need for separate mixers.

  • Surface mounted allows for ease of inspection and maintenance.

  • Tested and proven controls package.

  • Eliminates final clarifiers and associated pumping.

Multi-reactor Batch and Single-reactor Continuous Flow designs available.