Surface Aeration System Modeling using COMSOL

G. Selembo, P. Selembo, J. Stanton, and G. Paulsen
University of North Carolina
Charlotte, NC

Surface aeration systems are used in the wastewater treatment industry for the transfer of oxygen in the activated sludge process. These systems are capital intensive and also require a significant amount of energy to operate. Scale-up and design of these systems is largely empirical, and due to the size of these systems, modifications for experimental testing can be economically prohibitive. Small improvements in system efficiency can result in substantial savings in electrical costs.

The goal of this project is to develop improved techniques for predicting surface aeration system performance. The rotating machinery model (part of the CFD module within COMSOL) is well suited for the structure of the problem. Modeling of these systems involves many aspects of COMSOL, including free surface modeling, multiple mass transfer zones, and two phase bubbly flow.