A.R. Völkel, M.H. Lean, N. Chang, J. Seo, A. Kole, H.B. Hsieh, K. Melde
hydrodynamic separation, dissolved contaminants, adsorption, precipitation
This paper describes a two-stage water treatment technology for removal of dissolved contaminants that is relevant to many water matrices. Removal is achieved by adapting conventional adsorption, coagulation and flocculation, or lime softening and/or soda ash (or pearl ash) protocol as a pre-treatment mixing conditioning step followed by a novel hydrodynamic separation stage. This hydrodynamic separator (HDS) uses centrifugal force to create fluid flow patterns that sweep particles in the transverse direction so that they relocate to either of two neutrally stable force equilibrium positions where they concentrate into a band. By placing a flow splitter at the end of the channel we obtain a clean effluent stream and a concentrated particle stream. Advantages of this technology over conventional practice include: small foot print, low energy requirement, rapid process, and continuous flow operation. Added benefits include no moving parts, high scalability, high modularity in construction, and low cost in materials and TCO. This technology has been tested on many raw water matrices. Results for efficient removal of scaling agents and dissolved hydrocarbon are discussed.