Laserfiche WebLink
3 E×ISTING WASTEWA~ER FACIUT)ES <br /> <br />TABLE 32.2-1 <br />WPCF Pretreatment Facility Unit Processes and Equipment <br />MWMG Facilities Plan, Eugene-Springfield <br /> <br /> Capacity, (each~otal <br /> Equipment Type Quantity flrm~/totalb) <br /> <br />Screenings Grinder Inhne (rated at 150 cubic feet of screenings 2 1,000/1,000/2,000 gpm <br /> per hour) <br /> <br />Grit Removal Aerated Grit Chambers (101,000 galtons 4 58.3/1751233 mgd <br /> each; design cdteda of 2.5 minutes <br /> detention time at peak flow) <br /> <br />Grit Slumj Pumps Recessed impeller 4 300/900/1,200 gpm <br /> <br /> Preaeration Chambers (152,000 gallons each; design 4 14.6/43.8/58.4 mgd <br /> criteda of 15 minutes detention time at <br /> average flow) <br /> <br />Screenings Impeller Washer 2 2,000/2,000/4,000 gpm <br />WashedOompactor Shafted Screw Conveyor and Compactor <br /> <br /> Compacted Shaftless, Dual-Drive, Reversing <br /> Screenings/Gdt Grit 2 900/900/1,800 lb/hr <br /> Conveyor Screenings 2 1,400/1,400/2,800 lb/hr <br /> <br /> Solids Loadout Conveyor Shaftless Screw <br /> Gnt 2 900/900/1,800 Ih/hr <br /> Screenings 2 1,400/1,400/2,600 lb/hr <br /> <br /> Gnt Separation Cyclones 4 300/900/1,200 gpm <br /> Classifiers 2 600/600/1,200 gpm <br /> <br /> Notes: <br /> a Total firm capacity is with largest unit out-of-service. <br /> b Total capacity is with all unas in service. <br /> <br /> Primary Treatment <br /> The MWMC WPCF currently uses a total of four primary clarifiers to treat screened and <br /> degritted raw sewage. The existing primary clarifiers are circular, have outboard launders, <br /> and are 135 feet in diameter. Each clarifier receives effluent from the plant's existing <br /> headworks through a dedicated 60-inch-diameter pipe. Primary sludge is accumulated at <br /> the bottom of the clarffier and thickened through compaction. Primary sludge solids are <br /> drawn off with intermittent sludge pumping and a thin sludge blanket is maintained within <br /> the clarifier. Table 3.2.2-2 summarizes the prin-mry treatment processes and equipment. <br /> <br /> MWMC_3 0_REV11 DOC 3-9 <br /> <br /> <br />