System will be the fifth of its kind in the state of Alabama
The city of Florence, Ala.'s Wilson Lake Water Treatment Plant will be home to Alabama's fifth MIEX treatment system. The 8 million gal per day system, designed in conjunction with Engineers of the South, will remove dissolved organic carbon (DOC) from the plant's Tennessee River raw water source to reduce disinfection by-product (DBP) formation. The system will be applied as pretreatment to the plant's existing conventional treatment process and will allow for compliance with the U.S. Environmental Protection Agency (EPA) DBP regulations.
The city selected the process based on its ability to remove sufficient DOC from the plant's raw water source to reduce DBP formation by more than 40%, ensuring compliance with Stage 2 DBP Rule requirements. Additionally, its positive impact on the plant's downstream treatment processes such as coagulation, sedimentation and filtration were also an important consideration for the utility.
The Wilson Lake Water Treatment Plant recently received its Six-Year Optimized Plant Award from the Alabama Department of Environmental Management (ADEM), for meeting process optimization goals set by ADEM and EPA. Installation of the MIEX system is expected to help the plant continue to optimize its process in the future. The DOC removal achieved by MIEX pretreatment was demonstrated to reduce the water's coagulant demand by 50%, which should reduce the utility's coagulant costs and solids generation as well as improve the performance of the plant's filtration process.
"From the time we saw the results of the first bench scale tests and the impact that MIEX treatment had on DBP formation and our coagulation process, we knew we had identified the right process for ensuring compliance with current and future DBP regulations,” said Mike Doyle, utilities director for the city of Florence. “We look forward to progressing with the construction of the system."
The water treatment plant construction project was bid in October 2012. Construction, by BH Craig, is expected to begin in late 2013, with system commissioning occurring in summer of 2014.