DESIGN OF ONE BILLION GALLON PER DAY FINE SCREEN FACILITIES FORTHE ADVANCED WASTEWATER TREATMENT PLANTAT BLUE PLAINS

摘要

The District of Columbia Water and Sewer Authority's Advanced Wastewater Treatment Plant atrnBlue Plains, with a design average daily flow of 370 million gallon per day (mgd), and designrnpeak flow of 1,076 mgd, currently utilizes coarse back clean/back return bar screens to screen therninfluent combined wastewater entering its two screening facilities. As part of an upgrade to thernplant’s headworks, the screening facilities will be retrofitted with 6-mm fine screens, screeningsrnconveyance systems and two screenings loading stations. The screenings facilities upgrades willrnbe constructed concurrently with upgrades to other major plant processes and installation of arnplant-wide computer control system. This paper presents the design features that werernincorporated to increase the reliability of the screenings removal process while minimizingrnmaintenance requirements. Additional design features integrated to overcome the constraints ofrnconstructing within existing facilities that must be maintained in continuous operation, duringrnseveral concurrent plant-wide upgrades, are also presented.