Accession Number : ADA134731

Title :   Chemical Clarification Methods for Confined Dredged Material Disposal.

Descriptive Note : Final rept. Oct 78-Sep 81,


Personal Author(s) : Schroeder,P R

Full Text :

Report Date : Jul 1983

Pagination or Media Count : 150

Abstract : This report presents the results of verification studies on chemical clarification methods for dredged material disposal developed during the Dredged Material Research Program and provides laboratory procedures and design guidelines for designing treatment systems to clarify the effluent from a dredged material containment area. Guidelines are also presented on operating the systems and estimating the treatment costs. Thirty-five chemicals were screened in laboratory tests to determine which types of polymer were most effective in clarifying suspensions of fine-grained, freshwater sediments. Moderately high molecular weight, highly cationic polyamines performed well on the suspensions tested, which ranged in solids concentration from 0.21 to 2.1 g/l. The required polymer dosage increased with increasing solids concentration. The required dosage decreased as the mixing conditions were improved. Three field demonstrations were performed to determine the technical and economic feasibility of clarification by flocculants and to develop a treatment system that is simple, economical, and adapted to the disposal operation. Field tests showed that the treatment system was very effective. A preliminary laboratory and field investigation was performed to examine the polymer dosage requirements to treat dredged material slurries by injecting polymer into the dredge pipeline. Laboratory jar test procedures are presented to select an effective polymer (including dosage and feed concentration), to determine the mixing requirements, and to determine the mixing requirements, and to determine the relationship between the influent solids concentration or turbidity and the required polymer dosage.

Descriptors :   *Waste disposal , *Waste treatment , *Dredged materials , Chemicals , Waste management , Methodology , Laboratory procedures , Containment(General) , Effluents , Operation , Costs , Polymers , Suspended sediments , Fine grained materials , Molecular weight , Cations , Amines , Dosage , Solid wastes , Flocculants , Slurries , Concentration(Composition) , Laboratory tests , Field tests , Test methods

Subject Categories : Water Pollution and Control

Distribution Statement : APPROVED FOR PUBLIC RELEASE