AWWA WQTC62513

This slide presentation presents a treatment plant optimization effort by the Birmingham, Alabama, Water Works Board. Project objectives included: design and build a mobile conventional treatment pilot plant; use pilot plant to test treatment modifications off-line; and, work to optimize current treatment practices to meet upcoming regulations as well as test alternative processes, e.g. granular activated carbon (GAC). The overall testing approach included: design and construction of pilot plant; bench scale tests for screening of process alternatives; pilot testing for verification of selected alternatives; and, recommendations and implementation. A second part of the project involved a distribution system pilot study with objectives that included: investigate possible leaching of aluminum, lead, and copper already present in the distribution system during a transition from higher to lower pH levels system-wide; quantify concerns about possible destabilization of protective calcium carbonate layers on unlined cast iron and galvanized pipe; evaluate switch from free chlorine to chloramines on pipe corrosion; assess advantages / disadvantages of switching to a corrosion inhibitor for corrosion control; and, recommend a corrosion inhibitor for full-scale consideration if necessary. Overall pilot test results for treatment plant optimization included: optimized organics removal; maintain turbidity removal; and, reduce finished water aluminum, resulting in lower finished water pH. Overall pilot test results for the distribution system included: corrosion control strategy outlined; and, developed plan to minimize transient poor water quality with finished water pH change.