This paper describes a rapid in-line coagulation, flocculation, and separation process for water treatment. Innovations include rapid coagulation, floc conditioning, and pin floc separation. Spiral mixing structures with custom shear rates are developed to enhance aggregation kinetics of colloidal particles, resulting in 50% reduction in coagulant dosage and floc conditioning to create dense uniformly sized pin floc. Fluidic separation structures with designed size cut-off and efficiency are developed for hydrodynamic separation of the pin floc, eliminating sedimentation, and reducing process time from hours to minutes. Advantages of this small footprint, compact, low energy system include significant savings in reduced land use, chemical cost, and operational and maintenance overhead. Applications include municipal water, waste water reclaim, industrial water, pre-treatment for RO, and almost any instance where this generic capability to separate neutrally buoyant particles may be used to reduce TSS loading from a fast flowing fluid.
Lean, M.; Kole, A.; Seo, J.; Voelkel, A. R.; Chang, N. E.; Hsieh, H. B.; Melde, K. Innovative hydrodynamic clarification for water treatment. Singapore International Water Convention - SIWW 2009; 2009 June 23-25; Singapore.