Alpha Factors in Full-Scale Wastewater Aeration Systems

Surface active agents depress gas transfer at gas-liquid interfaces. They are present as measurable trace contaminants at all environmental and at most industrial gas-liquid interfaces. This paper presents the results of several studies, including lab and full scale studies that show the depression of gas transfer, usually quantified by the alpha factor, can be related to the Reynolds number and the level of wastewater treatment. Our results offer a tool for mass transfer prediction from flow regime and dynamic surface tension properties.