Provide PDF Format
AWWA ACE68641
- Pilot Testing of Dissolved Air Flotation and Inclined Plate Settlers at Charleston's 118 MGD Hanahan Water Treatment Plant
- Conference Proceeding by American Water Works Association, 11/01/2008
- Publisher: AWWA
$12.00$24.00
This powerpoint presentation begins by providing background information on the Hanahan Water Treatment Plant in Charleston, South Carolina. Objectives of a pilot testing program included:verify bench-scale coagulation conditions;monitor performance of pilot units;determine impacts of various loading rates(settled water quality andfilterability);determine optimal clarification operating conditions;evaluate performance of dual-media filters;evaluate clarification and filtration performance for removal ofturbidity,TOC, UV<sub>254</sub>, andapparent color; and,evaluate the operational robustness of each unit. The presentation presents comparisons of: clarification; filtration; organics removal; and, optimal run. A technical and economic evaluation presents the following topics: LeopoldClari-DAF; IDI AquaDAF; MRI Plates; project costs; operating costs; and, 20-year present worth costs. Presentation summary of findings includes:overall treatment -- all three processes could provideacceptable treatment at optimized conditions;flocculation --fragile floc created challenging issues for all processes, longer floc times required than often seen, andfloc aid polymer important, particularly for plate settlers;plate settlers had higher median headloss rate (in/hr)than the DAF units in winter testing, in summer testingmedian headloss rates were similar; loading rates of approximately 6 gpm/sf (Leopold), 8gpm/sf (IDI), and 0.25 gpm/sf (MRI) are appropriate. Atthese loading rates, the plate settlers had the lowestcapital, operation and maintenance (O&M), and present worth cost;utilize plate settler technology at a loading rate of 0.25gpm/sf for future clarification basins --good process performance during pilot testing,familiarity of plant staff with process,lowest capital and O&M costs, andsize basin for potential future loading rate of approximately0.4 gpm/sf pending results of continued optimizationefforts. Includes tables, figures.