AWWA WQTC71506

This powerpoint presentation begins by providing a brief overview of how water softening controls inorganic scaling and fouling problems. A new generation of reactor, TURBOMIX, is presented that is equipped with antivortex baffles, internal sludge recirculation, and a draft tube reactor that enhances mixing efficiency and produces a highly homogenous mixture. A laboratory scale investigation is presented that had the following objectives: to reduce CaCO₃ nucleation and crystals formation time to < 20 minutes; and, to determine the impacts of solids/sludge recirculation ratio, water quality, and co-occurring contaminants [PO₄]. A pilot scale investigation was conducted on-site for six weeks to evaluate two technologies with and without sludge recirculation: CFSTR + sand ballasted settling [ACTIFLO system]; and, TURBOMIX + sand ballasted settling [ACTIFLO system]. The study compared CaCO₃ crystal formation kinetics and determined the impact of sludge recirculation. Includes figures.