Experimental study on flocculation-accelerated deposition of dredger fill

After hydraulic reclamation of the dredger fill, the mud needs some time to deposit. The reinforcement treatment cannot be carried out until the sludge-water separation is completed and the separated water is drained. Through laboratory tests, the effects of chemical agents, drainage condition, slurry concentration and soil weight on the sludge deposition process are investigated. The field tests on one hundred thousand square meters are carried out. The results show that the early-stage deposition velocity of sludge increases 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. Improving the weight of soil and mud concentration has a certain effect on the deposition of the construction site. The chemical reinforcement method is feasible.