SWIRL TECHNOLOGY - ENHANCEMENT OF DESIGN, EVALUATION, AND APPLICATION

While different forms of swirl and vortex technologies have been devel oped during the last thirty years, their major function has been the d ual purpose of how regulation and settleable-solids concentration for combined sewer overflows. A variety of opinions have developed regardi ng the application of these technologies, which vary from overwhelming support to reservations of their effectiveness. Performance of swirl/ vortex devices depends on the settling characteristics of the suspende d solids and the fraction of dissolved solids in the storm flow. When correctly installed with other controls of the combined-sewerage or se parately sewered storm-water system, swirl/vortex devices can play an important role in combined sewer overflow and storm-water discharge po llution control. Reliable determination of performance depends princip ally upon accurate sampling techniques, suspended solids and other pol lutant analyses, and settling-velocity distribution of the influent an d effluent. Simultaneous flow-rate measurement synchronized to samplin g times is also necessary. This paper discusses design, evaluation, an d application practice enhancements for the use of swirl/vortex techno logies as part of a combined sewer overflow and storm-water pollution control system.