Citation
Lean, M. Rapid, Low energy, compact, scalable water treatment. Emerging Technologies Summit 2008; 2008 October 26-28; San Diego, CA.
Abstract
This presentation describes a highly scalable fluidic technology that presents a transformative approach to the practice of conventional water treatment. Features include: a high throughput, purely fluidic, continuous flow, membrane-less, size selective method for particulate extraction; and accelerated agglomeration kinetics from mixing and transporting chemical coagulant and raw water in confined channels. The former involves centrifugal force created in spiral flow channels to extract buoyant and denser particles, and transverse hydrodynamic forces to separate neutrally buoyant particles and divert the bands for extraction. The latter results in reduced chemical coagulant dosage by 50% due to the narrow size distribution resulting from fluid shear effects of seed particles for agglomeration. Together, the combined effects allow for in-line coagulation, floc formation, and immediate separation of pin floc from the effluent stream. This integrated approach using both spiral mixers and spiral separators eliminate flocculation and sedimentation steps, resulting in significant savings in capital cost (reduced land area, equipment, and infrastructures), and operations and maintenance cost (reduced chemical use, low energy, and faster processing time from raw to finished water). This technology is also directly relevant to many other applications including: industrial water purification, waste water reclaim, power plant cooling tower, pre-treatment for RO, and almost any instance where reduction of TSS loading prevents clogging and extends the time between cleaning for many MF and UF membranes.