Aeration Control

Aeration Control and Energy Saving Techniques


We have extensive experience in designing, developing and commissioning aeration control systems and blower control systems for the treatment of waste water/effluent. We have worked with most of the UK water companies, directly or via the major process design companies. We work worldwide, with recent design and commissioning projects in Australia, USA, South Africa, Brazil and China. We also provide control systems for industrial effluent treatment such as in the paper manufacturing process and food industries.

With our experience of aeration and blower control systems and exposure to different philosophies, we are able to implement energy efficient solutions. We implement a range of different algorithms to achieve effective and efficient operation of the blowers, pressure control and DO control.


The control techniques include:

  • DO control direct from blower output
  • DO control via flow control valves using PID algorithm
  • DO control via flow control valves using incremental algorithms including “direction of change”
  • Pressure control using diurnal profile
  • Pressure control using “most open valve” with incremental control
  • Pressure control using “most open valve” with direct proportional control
  • Pressure control with “Setpoint Creep”

These control techniques are used mainly to reduce the blower discharge pressure to give significant energy savings. A small reduction in the blower discharge pressure will result in significant energy savings - a rule of thumb we have found is that by reducing the Blower Discharge Pressure by 10 mBar you achieve a 1% energy saving.


Whilst much of our work has been with the highly efficient HST blowers, these techniques can be applied to existing aeration systems. The savings achieved will be greater with the older (less efficient) blowers.


We have the skills to review existing control system installations and design cost effective improvements to give immediate energy savings. Often no additional instrumentation or equipment is required and so investment is relatively small, with minimum disruption to the operating plant. Our engineers can design the efficient control algorithms, modify the control system and test and commission on site. Our experience covers all the major PLC and SCADA manufacturers including the legacy systems.


Whether you are seeking a review of your current systems or a complete redesign, a relatively small investment to implement the latest control techniques will result in real energy savings.