Flocculation batch settling

Scott K.J., 1970. Continuous thickening of flocculated suspensions - comparison with batch settling tests and effects of floe compression using pyrophyllite pulp, Ind. Eng. Chem. 

There is a gradual transition from particulate setthug into the zone-settling regime, where the particles are constrained to settle as a mass. The principal characteristic of this zone is that the setthug rate of the mass, as observed in batch tests, will be a function of its solids concentration (for any particular condition of flocculation, particle density, etc.). 

Conditions favoring efficient separation of flocculent metal precipitates in a basin include a low surface overflow rate, adequate depth, and inlet and outlet designs for a uniform velocity field with minimal short circuiting or stagnation. Solids separation is likely to limit the overall efficiency of metals removal in treatment, so pilot studies include batch and continuous flow settling column studies.18... 

The flocculation process was scaled up to treat 20,000 gallons per batch. The supernatant from each batch was analyzed for dioxin, then treated with activated carbon for removal of residual organics The settled floe was returned to the lagoon for dewatering. 

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