Wastewater from the Lucas County collection system enters the WRRF through a 90-inch trunk sanitary sewer. Liquid ferrous chloride is injected into the raw influent sewage as an odor control and phosphorus removal aid. The influent wastewater is then split to the East and West Facilities.
Both sections utilize filter screens to remove material greater than 1/4" in size from the waste stream. The filtered influent then goes through grit removal in both facilities. The East portion utilizes an aerated grit chamber for grit removal while the West portion has a vortex type grit removal unit. The screenings and grit removed from the influents are transferred and stored on the plant’s sand filter drying beds, and then transported to a local landfill for disposal.
Both the East and West Facilities influent flows are measured via Parshall flumes following preliminary treatment. The influent wastewater is then pumped to the primary settling tanks. Primary sludge (including raw and waste activated sludge) is pumped from the primary clarifiers to the anaerobic digesters using progressive cavity pumps.
The primary effluents then flow by gravity to the aeration basins. Ferrous chloride is added to the aeration basin influent for both plants as a phosphorus removal aid. The primary effluent then receives secondary treatment via the activated sludge process in the aeration basins. The mixed liquor from the aeration basins then flows to the final clarifiers for solids separation from the secondary effluent. The clarified effluent flow is then measured in each plant via a Parshall flume prior to ultraviolet disinfection. The East & West effluents are then re-combined and discharge to the Maumee River.
As previously mentioned, the primary sludge from both the East & West Facilities are pumped to one of the three primary anaerobic digesters for stabilization, and then transferred to the secondary digester.
Methane gas that is produced in the digesters and is used to run the generators that produce electric power and hot water for the Digester / Cogeneration Complex including digester heating.
Digested sludge from the secondary digester is pumped to a centrifuge (with a back up belt filter press) for dewatering. The dewatered sludge is then hauled and stored on a sludge storage pad.
The dewatered sludge is land applied as Class B biosolids by a hauling contractor.