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Water solution: Boost your wastewater plant aeration performance thanks to a single integrated control system


Value proposition

Main drivers:
Reduce power consumption and operating costs.
Improve effluent quality.
Optimizating oxygenation and sludge injection in aeration process.

Solution in brief:
Automation control is key in three control areas of the activated sludge sewage treatment plant.

a. The aeration automation control - air blowers are driven by variable speed drive to optimize the flow according to the biological process demand.

b. The Return Activated Sludge (RAS) automation control - essentially to maintain the F/M ratio (Food to micro-organism ratio) in the aeration tank MLSS (mixed-liquor suspended solids) .

c. The Wasting Activated Sludge (WAS) automation control - base the control on calculations that utilize mixed liquor (ML) and return activated sludge (RAS) total suspended solids (TSS) concentrations.

Value propositions:

  • Saves 20 - 30% of power consumption of blowers by reducing power consumption of aeration blowers. 
  • Increase plant operation stability by improving F/M (food to micro-organism) ratio control accuracy and accuracy of solids inventory control. The F/M ratio maintained well will bring years of trouble free sewage treatment plant operation (STP) operation.
  • Improve efficiency and reduce operating costs by reducing the need for manual sampling and thus the time required for sampling, sample processing, and eliminates human errors associated with wasting calculations and lag time.
  • Retrofitting old wastewater treatment plants with automated blower output control.

Differentiation factors:

  • A single integrated control system optimizes the overall plant performance.
  • One-Schneider point-of-contact and turnkey project capability.
  • To establish good references with major WWTP EPC (engineering, procurement & construction) players





Main characteristics

Oxygen sensors of ORP instrument should be well placed in the anoxic-aeration tanks to send 4 - 20 mA signals to the PLC.
  • The DO concentrations in the aeration tank should be in the range of 1.5 to 4 mg/L. The DO level in the anoxic phase should be zero or near zero, i.e. without oxygen.
  • The dissolved oxygen content will remain at the DOCO (DO cut-off) so long as the chemical constituency of the sewage in-coming to tank remains the same and within the capabilities of the system and the oxygenation process continues with a constant air supply by weight.
  • DO should be adequate at all times in the system. When oxygen limits the growth of microorganisms, filamentous organisms may predominate and the settleability and the activated sludge process may be poor.
  • Proper food-to-microorganism (F/M) population ratio is the single most important parameter affecting the efficiency of an activated sludge system and the health of the biomass.

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Solution breakdown

Main services:
  • Engineering services: Services
Main products & systems: