Derivation and Verification of the Breakage Rate Coefficient during Flocculation Process Based on Shear Strength

Abstract:

The dynamics of flocculation is always one of the most interesting and difficult points for water treatment. The applicability of existing breakage rate coefficients was restricted due to the limitations of their theoretical derivation. In order to solve this problem, a breakage rate coefficient of flocculation process was derived based on shear strength. It could be described by the equation "s(m)=E₀Fr^1.2m^1/D". Then it was applied to a flocculation model which described the change of particle size distribution during flocculation. Laboratory scale experiments were carried out to verify the feasibility of the new breakage rate coefficient with the typical surface water in northwest China characterized by low temperature and low turbidity. Results indicated that both the change of particle size distribution with time and the effects of operation variables on the stable particle size distribution could be excellently simulated, agreeing well with the experimental results with the relative error ranged from 3% ~ 17%. It was demonstrated that the breakage rate coefficient based on shear strength could be used to describe the breakage rate of flocs during flocculation.

• Periodical: Advanced Materials Research (Volumes 779-780)
• Pages: 1482-1489
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.779-780.1482
• Online since: September 2013
• Authors: Jian Liu, Min Zhou, Jian Hao Zhou, Qi Chao Hu, Jun Guo He
• Keywords: Breakage Rate Coefficient, Flocculation, Low Turbidity, Low-Temperature, Shear Strength, Water Treatment

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