Abstract
This study focuses on the effect of mixing hydrodynamics, generated in unbaffled square stirred tanks with different liquid-level heights (H), on floc growth during flocculation over the same shear-rate range (Gave = 10–70 s−1) by using an in-situ recognition system for floc morphology. The hydrodynamic environments under each combination of H and Gave were characterized by calculated circulation time (tc) and impeller tip speed (Nd). It was found that the temporal evolution of floc size appeared to be sensitive to the value of H at a given Gave, and with increasing Gave, greater difference occurred at the same flocculation moments for different H-value cases. Also, under a fixed Gave-value condition, the H-value effect on floc size evolution at steady state of flocculation was shown to largely depend upon the predominant growth mechanism(s). An appropriate liquid-level height should be required to bring about an optimal combination of tc and Nd, thereby maximizing floc growth rate under both aggregation-dominated and breakage-dominated circumstances for enhancing floc formation and subsequent particle removal efficiency. The present study may provide useful insights into the design and operation of stirred-tank reactors for flocculation.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
