loading page

Combining continuous flow aerobic granulation using an external selector and carbon-efficient nutrient removal with AvN control in a full-scale simultaneous nitrification-denitrification process
  • +3
  • Pusker Regmi,
  • Belinda Sturm,
  • Devinda Hiripitiyage,
  • Nancy Keller,
  • Sudhir Murthy,
  • Jose Jimenez
Pusker Regmi
Brown and Caldwell

Corresponding Author:[email protected]

Author Profile
Belinda Sturm
The University of Kansas
Author Profile
Devinda Hiripitiyage
The University of Kansas
Author Profile
Nancy Keller
City of Pueblo
Author Profile
Sudhir Murthy
NEWhub
Author Profile
Jose Jimenez
Brown and Caldwell
Author Profile

Abstract

The James R. Dolorio Water Reclamation Facility in Pueblo, Colorado, uses AvN aeration controls to lower aeration energy while promoting carbon-efficient nutrient removal and hydrocyclone-based wasting to achieve SVI improvements and process intensification. The results from the full-scale installation showed that hydrocyclone-based wasting helped improve settling characteristics by reducing the SVI from 200 ± 52 mL/g to 83 ± 22 mL/g within weeks of operation. PAO and nitrifiers were preferentially retained in dense flocs and granules, while lighter heterotrophic and filamentous organisms were preferentially wasted, thus uncoupling the SRT of these two fractions relative to overall SRT. The SRT of dense aggregates was estimated at 14.4 ± 3.4 days and for lighter flocs at 7.1 ± 2.3 days. The use of AvN control with continuous low DO conditions resulted in low DO conditions (< 0.4 mgO2/L) reducing air demands by 50% while providing excellent nitrogen (effluent TIN < 11 mg/L) and TP removal (effluent TP < 1 mg/L) at low primary effluent COD/N ratio of 6.0. The presence of comammox was demonstrated through molecular analysis, while ex-situ batch tests revealed the presence of DPAO, which could have attributed to the energy and carbon-efficient biological nutrient removal.