Laserfiche WebLink
MWMC FACILITIES PLAN <br /> <br />TABLE 3.2.2-6 <br />WPCF Anaerobic Digestion Unit Processes and Equipment · <br />MWMC Facilities Plan, Eugene-Springfield <br /> <br /> Capacity, (each/total <br /> Equipment Type Quantity firma/totalb) <br /> <br />Digesters Anaerobic, fixed cover, 85-foot-diameter, 3 19,432/38,864/58,295 lb VSS/day <br /> 27.6 foot SWD, active volume = 1.14 MG <br /> each, DWMM SLR = 0.15, DWMM SRT <br /> =15 days <br /> <br />Biosolids Storage Fixed cover, 60-foot-diameter 2 360,000/360,000/720,000 gal <br />Tanks <br /> <br />Digested Sludge Progressive cavity with AFD, 75 hp 2 430/430/860 gpm <br />Pumps <br /> <br />Notes: <br />a Total firm capacity is with largest unit out -of service. <br />bTotal capacity is with all units in service. <br /> <br />Facultative Sludge Lagoons and Brying Beds <br />The FSLs are located at the BMF facility offsite of the WPCF. The lagoons were constructed <br />to provide storage and further stabilization of digested biosolids received from the WPCF. <br />Anaerobically digested biosloids are pumped from the sludge holding tanks at the WPCF <br />through a 5.5-mile-long pipeline, to the four facultative lagoons at the BMF Facility. The <br />lagoons provide the additional detention time for natural processes to further stabilize the <br />biosolids and reduce pathogens. <br /> <br />Sealed asphalt drying beds provide for the stabilized biosolids to be dewatered for 6 to <br />10 weeks in the dry season. Dewatered biosolids are recycled through land application on <br />cooperative farms. Supernatant from the lagoon is returned to the WPCF. Table 3.2.2-7 <br />summarizes the biosolids stabilization unit processes and associated equipment. <br /> <br />TABLE 3.2.2-7 <br />WPCF Biosolids Stabilization Unit Processes and Equipment <br />MWMC Facilities Plan, Eugene-Springfield <br /> <br /> Capacity, (each/total <br /> Equipment Type Quantity firma/totalb) <br /> <br />Biosolids Stabilization Facultative lagoons, 6.25 acres 4 6,806/20,419/27,225 lb VSS/day <br />Lagoons each, 13.5 ft depth <br /> <br />Drying Beds Asphalt lined, 1.85 acres each, 0.48 13 1,393 CY <br /> ft depth, 67 lb/cf density <br /> <br />Notes: <br />aTotal firm capacity is with largest unit out -of service. <br />b Total capacity is with all units in service. <br /> <br />Biosolids Dewatering <br />The original design provided for the stabilized biosolids to be dewatered for 6 to 10 weeks <br />in thirteen sealed asphalt drying beds. However, lower than anticipated solids processing <br />efficiency (primarily because of variable summer weather conditions) required the addition <br /> <br />3-14 MWMC 3.0 REV11DOC <br /> <br /> <br />