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http://dx.doi.org/10.17137/korrae.2020.28.4.69

A Study on the Optimization of Sedimentation Efficiency through Controlling Stirring Speed and Baffle Angle  

Kwak, Sung-Keun (DOHWA Engineering Co., Ltd.)
Kim, Choong-Gon (Bioresource Center, Institute for Advanced Engineering)
Publication Information
Journal of the Korea Organic Resources Recycling Association / v.28, no.4, 2020 , pp. 69-75 More about this Journal
Abstract
This study was conducted to improve the solid-liquid separation efficiency of clarifiers. To do so, the study did a bio-flocculation experiment simply by controlling the stirring speed (rpm) and baffle angle of a clarifier on a lab scale, but without using a coagulant. For the purpose of the experiment, the feed wall of a clarifier was so improved that a baffle could be installed on the clarifier. Then, it was ensured to change its stirring speed (to 0.0rpm, 0.6rpm, and 1.2rpm), with the angle fixed at 10°. As a result, it was found that concentration efficiency increased by 2.0%, and effluent removal efficiency (SS concentration) by 7.8%, at a stirring speed of 0.6ppm. This indicates the bio-coagulation efficiency of sludge increased with changing stirring speeds. Then, the baffle angle of the sedimentation unit was changed to analyze how the changed baffle angle would affect the sedimentation of sludge. As a result, it was found that the compression of sludge interface was very effective at a baffle angle of 20°. It is hoped that these experimental findings will be useful in improving the sedimentation efficiency of circular clarifiers.
Keywords
Sedimentation unit; Bio-flocculation; Circular clarifier; Baffle; Stirring speed;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
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