OXYGEN MASS-TRANSFER FUNDAMENTALS OF SURFACE AERATORS

The current state-of-the-art oxygen mass transfer analysis for surface aerators is essentially limited to the first-order, exponential model employed in the ASCE Standard for the Measurement of Oxygen Transfer in Clean Water. This simple model has been used for several decades to characterize the oxygen mass transfer performance of surface aerators as well as many other types of aerators. This study develops a more f undamentally rigorous oxygen mass transfer model for surface aerators which provides a more physically realistic description of the actual o xygen transfer mechanisms. This new oxygen mass transfer model separat es the oxygen transfer process into a liquid spray mass transfer zone and a surface reaeration mass transfer zone. The model independently a nalyzes the oxygen transfer process within these two distinctively sep arate zones and provides the methodology and techniques for quantitati vely determining the oxygen transfer rate within each of these importa nt, but fundamentally different, oxygen mass transfer zones.