In the wake of reports that utilities with anaerobic digestion have poor dewaterability conditions after implementing enhanced biological phosphorus removal (Bio-P) processes, the Water Environment & Reuse Foundation is partnering with Bucknell University to determine the viability of Bio-P.

Solids handling is a critical component of wastewater treatment, providing an opportunity to recover valuable resources such as energy, nutrients and carbon-rich soil amendments. However, it can comprise 50 percent of overall treatment costs to the utility.

A large portion of these costs are associated with final dewatering, in particular for the use of polymer. It has been reported that utilities with anaerobic digestion have poor dewaterability conditions after the implementation of enhanced Bio-P removal processes, and that the impact is serious enough to make Bio-P uneconomical from a whole-plant perspective.

In order to assure the viability of Bio-P, WE&RF has entered into a contract with Bucknell University to determine if this phenomenon is more widespread, and to better understand and address dewaterability performance and its impact on Bio-P and P-recovery.

Discussions from the Water Environment Federation, WE&RF and Leaders Innovation Forum for Technology’s Intensification of Resource Recovery Forum showed a data gap and lack of consensus on reporting dewaterability parameters, along with an absence of a defined singular mechanism for the dewaterability impact.

The new research is intended to fill that gap and address the relevant fundamental mechanisms on dewaterability, effective plant operating parameters and overall performance of different enhanced biological phosphorus removal treatments.

This research will be conducted in two phases. Phase 1 will focus on fundamental laboratory-based research to test and develop the biofloc model hypothesis in an effort to help explain why Bio-P processes cause a deterioration in floc properties in anaerobic digesters, and a subsequent deterioration in dewaterability measured by a decrease in cake solids.

Phase 2 will include applied field research to further understand solutions to the poor dewaterability associated with Bio-P systems with an emphasis on solutions that enhance phosphorus recovery.

Utility partners have committed to pilot and full-scale testing. The project is anticipated to take 24 months, with laboratory research taking 10 months. 
For more information about the project, contact Christine Radke at cradke@werf.org.

The WE&RF is a 501(c)(3) charitable corporation seeking to identify, support and disseminate research that enhances the quality and reliability of water for natural systems and communities with an integrated approach to resource recovery and reuse. It also facilitates interaction among practitioners, educators, researchers, decision makers and the public.