Methodology for In Situ Column Testing to Improve Accuracy during Design and Specification of Aeration Systems

Abstract

When designing wastewater aeration systems, fine-pore diffusers are typically selected for their potential energy efficiency. Because aeration is one of the most energy-intensive unit operations during treatment, the accurate quantification of aeration performance parameters is crucial to minimize the process energy footprint. Oxygen transfer efficiency in process water is the key design parameter; however, performance indicators that account for fouling and increased pressure drop with time must be considered. Both fouling and pressure drop increase cause an increase in blower power requirements. This paper presents a new approach to improve this design procedure, without altering the technical structure of the classical approach. Although the administrative and bidding milestones are underway (i.e., in the first few months of the project), an independent aeration team can test candidate diffusers suitable for design in an in situ aeration column. Subsequently, an extended fouling test in the plant’s wastewater can be carried out within the design timing, providing the designers with site-specific aeration performance data. This methodology improves the accuracy of the design process and increases overall energy savings.