Laboratory Test Study on Rapid Chemical Deposition of Fresh Dredger Fill

Abstract

After hydraulic reclamation of the dredger fill, as the deposition of surface sludge requires a relatively long time, the consolidation treatment cannot be immediately performed until the sludge-water separation is completed and the separated water is drained. The laboratory test makes a research on the effects of chemical agents and drainage condition on the sludge deposition process. The research shows that the early-stage deposition velocity of sludge is increased obviously and the sludge-water separation time is shortened after water hydrophobing agents and polymeric flocculants are added. However, the later-stage deposition velocity is slow and the deposition strength is low. Thus, certain drainage conditions are required to increase the later-stage deposition velocity and deposition strength of sludge.