Mechanism of Sediment Flocs Formation in the Three Gorges Reservoir

Abstract:

Settling velocity of sediment increases if flocculating occurred, and this enlarges deposition in reservoirs. According to water environmental factors in the Three Gorges reservoir, potential energy and forces between particles are evaluated based on DLVO theory. The critical water dynamics conditions were obtained by comparing extremum in synthetic potential curve and kinetic energy caused by relative velocity between particles. It is found that sediment flocculating is apt to happen when water level is high according to flow dynamics in the Three Gorges reservoir. The flocs are relatively loose and which is prone to be broken by water shear force. So the settling velocity of the flocculation is limited and the critical diameter of sediment is 0.019mm under which the sediments are affected by flocculating, and the settling velocity should be revised according to the limited settling velocity of flocculation when sediments are smaller than the critical diameter.

• Periodical: Advanced Materials Research (Volumes 955-959)
• Pages: 2988-2995
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.955-959.2988
• Online since: June 2014
• Authors: Dang Wei Wang*, Zu Wen Ji, Zhan Di Dong, Hai Hua Hu
• Keywords: Sediment Flocculation, Settling Velocity, Three Gorges Reservoir

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