Removal of Suspended Clay Particles in Water by Weathered Volcanic Ash-Based Material


  • Nga Nguyen Thi Hang Department of water resources engineering, Thuy Loi University, 175 Tay Son, Dong Da, Ha Noi-100000, Viet Nam


Water treatment, Flocculation, Kaolinite, Montmorillonite, Surface charge neutralization.


The present study aims to investigate removal capacity of suspended clay particles in water by a flocculant prepared from weathered volcanic ash rich in allophane and imogolite. The optimum flocculant dosage and pH values of suspensions required to achieve maximum removal of clay particles were determined. Flocculation experiments of clay suspensions were conducted with jar test device in the laboratory. The results indicate that the flocculant performs well in removing clay particles. The highest efficiency was kaolinite removal approx. 98%), and lower capacity was with montmorilonite (approx. 93%). The optimum solid ratios of 0.2:1 and 1:1 are determined for flocculant to remove kaolinite (Kao) and montmorilonite (Mon). Solution pH affects the clay particle removal. The acidic condition of suspensions enhances flocculation and removal efficiency. Sedimentation time of 20 min is necessary for completed flocculation process of clay particles with flocculant. The results of flocculation tests clay particles also suggest that volcanic ash-based flocculants removed kaolinite particles more effectively than for montmorillonite. 


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How to Cite

Hang, N. N. T. (2017). Removal of Suspended Clay Particles in Water by Weathered Volcanic Ash-Based Material. American Scientific Research Journal for Engineering, Technology, and Sciences, 35(1), 58–66. Retrieved from