Author(s): Shehua Huang; Kun Chen; Yang Tian; Tianyu Sui
Linked Author(s):
Keywords: Activated carbon particle; Microporous structure; Sedimentation rate; Density correction coefficient
Abstract: Powdered activated carbon (PAC) has good adsorption performance to impurities in industrial wastewater. The characteristics of activated carbon particles’ motion in water are closely related to sewage treatment efficiency. In this paper, the sedimentation characteristics of PAC particles are studied experimentally. The microstructures of PAC particles and the specific surface area are measured and analyzed firstly. The relationship between the particle size and density of the activated carbon particles and the pore structure parameters has been obtained. Then, sedimentation characteristics of PAC particles in still water are studied by referring to the measurement method of settling velocity. The theoretical settling velocity of activated carbon particle is calculated by using the Stokes formulation of flow over spherical particle at very small Reynolds numbers. By comparing the theoretical results with the experimental data, the moisture content of activated carbon in the water is discussed. The mixed density of the activated carbon particles in water is calculated and a formula for calculating the sedimentation rate of PAC particles is deduced. Finally, the factors influencing the settling velocity of the activated carbon are analyzed. The results show that the sedimentation rate of the activated carbon increases with the increase of the particle size and density. The water temperature was positively correlated with the settling velocity. In the non-flocculating concentration range, the settling velocity of activated carbon particles decreases with the increase of the concentration.
Year: 2018