Suspended solid abatement in a conical fluidized bed flocculator

doi:10.1007/s11783-012-0415-x

Front Envir Sci Eng

2013, Vol. 7

Issue (1) : 127-134 https://doi.org/10.1007/s11783-012-0415-x

RESEARCH ARTICLE

Suspended solid abatement in a conical fluidized bed flocculator

Dandan ZHOU¹, Shuangshi DONG¹(

), Keyu LI², Huizhong JIANG¹, Dandan SHANG¹

1. Key Laboratory of Groundwater Resources and Environment (Ministry of Education), Jilin University, Changchun 130026, China; 2. China Northeast Municipal Engineering Design and Research Institute, Changchun 130021, China

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Abstract

With the random movement of silica gel beads in a conical fluidized bed, micro-vortices resulting from the fluidization promoted the collision and aggregation of suspended fine kaolin powders. The abatement efficiencies of the suspended fine solids under several hydrodynamic conditions were studied, and a suitable control strategy for operating the conical fluidized bed flocculators was identified. The suspended solids abatement efficiency was found to increase with increasing Camp Number and flocculation time (T), but decreased with the increase of velocity gradient (G) within the range studied in this research (165.1–189.6 s^-1). The abatement efficiencies were all more than 60% at the range of G = 165–180 s^-1 and T = 15–33 s at an initial kaolin solid concentration of 150 mg·L^-1, polymer aluminum chloride dosage of 60 mg·L^-1 and sedimentation time of 20 min. However, the formation of flocs was influenced by the liquid backmixing. Excessive backmixing caused the breakup of flocs and resulted in difficulty for the fine powders to aggregate and sediment to the reactor bottom. The results of the calculated fractal dimension and measured free sedimentation velocity of flocs obtained at different runs showed similar flocs properties, and indicated an easy control strategy for sedimentation of the flocs.

Keywords conical fluidized bed flocculation velocity gradient

Corresponding Author(s): DONG Shuangshi,Email:dongshuangshi@gmail.com

Issue Date: 01 February 2013

Cite this article:

Dandan ZHOU,Shuangshi DONG,Keyu LI, et al. Suspended solid abatement in a conical fluidized bed flocculator[J]. Front Envir Sci Eng, 2013, 7(1): 127-134.

URL:

https://academic.hep.com.cn/fese/EN/10.1007/s11783-012-0415-x
https://academic.hep.com.cn/fese/EN/Y2013/V7/I1/127

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