Effects of symmetrically alternative rotating flow on flocculation

来源期刊：中南大学学报(英文版)2003年第4期

论文作者：徐继润 张育新 邢军 孙永正 徐海燕 刘正宁 康勇

文章页码：338 - 341

Key words：flocculation; shearing rate; symmetric and alternative rotating flow

Abstract: A symmetrically alternative rotating flow pattern was designed for flocculation process in order to produce large and dense flocs. The special effects of a symmetrically alternative rotating flow on the diameter and density of flocs were investigated. The results show that under the new fluid conditions, the primary particles on the outer part of the formed flocs may be cut down and the flocs contract at the end of the original rotating direction; then fluid changes its rotating direction, an opposite shearing is imposed to the flocs and makes some primary particles slide along the floc surface, leading to a denser floc; meanwhile, the broken and unflocculated particles on the trajectory may have opportunities to penetrate into or cohere to the flocs. Compared with the conventional rotating flow, the new-designed flow pattern can not only keep the floc size (even enlarge the floc diameter if a suitable flow is chosen) but also increase the floc density effectively.