Chemical Clarification of Dredged Material

Laboratory and design procedures have been developed for chemical clarification of dredged material containment area effluents based on results of laboratory and field tests. The design is suitable for normal disposal operations including remote locations, high and variable flows and solids loadings, and temporary and intermittent operation. The treatment system requires minimal equipment and operation. Low viscosity, highly cationic liquid polymer is applied at the drainage structure of the primary containment cell. Mixing for dispersing polymer and flocculation is provided by turbulence of flow through the discharge culvert. A small secondary cell is used for settling and storage of treated material. Design parameters are determined by jar tests. Major cost components are polymer, labor, and construction. The cost for equipment, labor, and polymer should range from $\$0.08/{\mathrm{yd}}^3-0.25/{\mathrm{yd}}^3$ $(\$0.10/m^3-0.33/m^3)$ (1981 dollars) of in situ sediment dredged and is dependent on the production rate, polymer dosage, and treatment system design.