Author(s): Ruicai Wang; Weijie Xu; Teng Wu; Jie Qin; Guilan Tao

Linked Author(s): Teng Wu, Jie Qin

Keywords: Dredged mud; Flocculants; Silty sand-to-clay ratio; Sedimentation time of mud; Sediment permeability coefficient

Abstract: Adding flocculants into dredged mud can achieve rapid sedimentation of solid particles. However, the flocculation treatment effect varies considerably due to extensive variation of the silty sand-to-clay ratio. In order to clarify the problem, the experimental study of flocculation was carried out by adding different types of flocculants. This paper analyzes the effect of the silty sand-to-clay ratio on mud flocculation in terms of flocculants dosage, sedimentation time of mud, sediment water content and sediment permeability coefficient etc. As the silty sand-to-clay ratio of mud increases, the results show that the optimal amount of anionic polyaerylamide (APAM) is gradually reduced while the optimal amount of poly alumina chlorine (PAC) gradually increased, and the sedimentation time of mud is gradually reduced but the sediment permeability coefficient increased. Among the experimental groups of APAM, PAC and no flocculants, the APAM’s flocculation had the shortest sedimentation time of mud, the largest decrease of sediment water content, and the largest increase of sediment permeability coefficient, but the upper liquid of the sample is a little turbid. While for the PAC’s flocculation, the sedimentation time of mud and the sediment permeability coefficient are between the APAM’s and no flocculants’, but its upper liquid of sample is clear. The results of the study may provide a reference for the engineering treatment of dredged mud.

DOI: https://doi.org/10.3850/IAHR-39WC2521711920221915

Year: 2022