• Available in steel or concrete tanks
  • Can be built in circular or rectangular shape
  • Suitable for small to medium plants
  • BBR of IFAS option available

Extended Aeration plants provide a low cost, odor and nuisance-free Sewage Treatment Plant that produces a high degree of treatment. Extended aeration treatment plants are used worldwide to provide simple and effective wastewater treatment.



  • Low capital operating costs
  • Excellent treatment performance with low sludge production
  • Stable during shock and stress loading
  • Fulfillment of regulatory requirements
  • Ease of installation
  • Low maintenance and operations requirements
  • Variable blower operation for seasonal load adjustments



The Extended Aeration Process, a modification of the Activated Sludge Process, effectively treats the contaminants in wastewater. The standard basis of design includes an aeration system, providing a 24-hour detention time and a final settling tank, with an effective 4-hour detention time. Diffused air is introduced into the aeration tank, this provides the proper environment for the development of aerobic bacteria. These bacteria thrive on the materials contained in the wastewater. The prolonged period of aeration, in addition, oxidizes a portion of the solids in the system. Oxygenation by diffused aeration provides operating flexibility and standby reserve to meet the demanding requirements of varied package plant applications. Separation of the solids from the mixed liquor developed in the aeration tank takes place in the settling compartment. The clarified effluent is withdrawn for reuse or discharged into a receiving stream from the top of the settling tank. The settled solids are rapidly pumped from the bottom of the settling tank back to the aeration system. These Extended Aeration Plants are proven workhorses, providing excellent Biochemical Oxygen Demand (BOD) and Total Suspended Solids (TSS) removal efficiency. Only minimal routine housekeeping and operational tasks are required of the plant operator.