Criteria for Distinguishing Floc Sedimentation and Gel-Like Network Sedimentation of Cohesive Fine-Grained Sediment in a Turbulent Flow

Zhongfan Zhu

College of Water Sciences, Beijing Normal University, Beijing, China.

DOI: 10.4236/gep.2014.25004                

Abstract

The study on the criteria used to distinguish floc sedimentation and gel-like network sedimentation of cohesive fine-grained sediment in a turbulent flow has rarely been carried out. In this preliminary study, we derive three criteria to distinguish these two different sedimentation phases by considering the comparison of the time that a characteristic floc takes to settle through mean distance between characteristic flocs and the time that it takes to move through the same distance under the influence of a turbulent flow. These criteria incorporate physical and chemical factors that have been verified to have some influences on the sediment flocculation in some published literatures, and a simple analysis result is found to be consistent with our qualitative understandings of flocculation phenomenon of cohesive fine-grained sediment.

Keywords

Criteria, Floc Sedimentation, Gel-Like Network Sedimentation, Cohesive Sediment, Turbulent Flow

Conflicts of Interest

The authors declare no conflicts of interest.

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