Flocculation process scale

Cluster fractals that are created by diffusion-limited flocculation processes are described mathematically by power-law relationships like those in Eqs. 6.1 and 6.5. These relationships are said to have a scaling property because they satisfy what in mathematics is termed a homogeneity condition 22... 

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. 

Sometimes the effect of the detention time is so strong that the overflow rate can be ignored and the scale-up is based on the so-called second order test procedure (as the flocculation process usually follows a second order reaction model ). The required detention time is determined by testing the residual solids concentrations in the supernatant under the conditions of mild shear. 

A similar technique to the Bureau of Mines trommel process called pellet flocculation has been used in Japan on a number of substrates on an industrial scale (47) using equipment made by the Ebara-Infilco Co. Combinations of inorganic salts such as lime with polyacrylamides are used as flocculants. 

Flocculation or clarification processes are solids-liquid separation techniques used to remove suspended solids and colloidal particles such as clays and organic debris from water, leaving it clear and bright. Certain chemicals used (such as alums) also exhibit partial dealkaliz-ing properties, which can be important given that the principal alkaline impurity removed is calcium bicarbonate—the major contributory cause of boiler and heat exchanger scales (present in scales as carbonate), although closely followed by phosphate. 

Another full-scale process combines catalytic oxidation including biodegradation, adsorption, precipitation/flocculation, and reverse osmosis [120]. 

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