Tube Flocculator

Objective and Motivations

The goal of any flocculation process is to transform suspended colloidal particles into flocs that can be removed by sedimentation. The design of sedimentation tanks is dictated by the settling velocity of the flocs. One of the goals for the AguaClara team is to develop a sedimentation tank that will form a fluidized floc blanket, which will help clean water as it flows into the sedimentation tank from the flocculator. To develop this floc blanket the flocculator must produce flocs that fall within a particular range of settling velocities. Therefore, it is important to research the parameters that affect flocculation and the resulting floc size distribution.

Our goal is to determine the parameters (such as optimal energy dissipation rate, hydraulic residence time, etc.) that will produce fast settling flocs that can remove the greatest percentage of the turbidity in the water.

The apparatus

Experimental apparatus

Research

*Influence of flocculator length and alum dosage on flocculation
*Fluid shear influences on flocculation
*Archive

FAQs, Basics, and Cleaning

If you are new to the team or would like to know more about the upkeep of our experimental setup, check out the basics. An excellent resource for information on the FReTA setup is Ian Tse's M.S. thesis: Fluid shear influences on hydraulic flocculation systems characterized using a newly developed method for quantitative analysis of flocculation performance. This thesis contains detailed information on the Process Controller states, rules, and set points as well as descriptions of the data analysis process.

References

Pratsinis, S., & Spicer, P. (1996). Shear-induced flocculation: the evolution of floc structure and the shape of the size distribution at steady state. Water Research, 30(5), 1049. Retrieved from Environment Index database.