City of Geneseo, Illinois

Geneseo’s Wastewater Treatment Plant uses process trickling filters and solids contact in which to treat the waste.  This is a biological process in which microorganisms remove the waste from the water by converting it into settlable matter that can be removed more easily from the system.  The plant is designed to handle an average of 1.5 million gallons per day and 4 million gallons per day during wet weather.

Process Stages:
Stage 1       The flow entering the plant from the collection system is screened through an automatic bar rack located in the head-works  where debris is removed before it can cause a problem for the pumping equipment.  Then the flow passes through the grit removal chamber  located near the control building  where inorganic material such as sand and gravel are removed to prevent wear on equipment and take up wasted space in the system.

 Stage 2       The flow is pumped up to the Primary Clarifiers  where 75% of the solids are settled out and pumped into the digesters .  Any floating material is skimmed off and added to the digesters  as well.

 Stage 3       The flow from the Primary Clarifiers is then gravity fed to the Rock Trickling Filter  where a mass of microorganisms (Zooleal) convert part of the waste that is suspended in the water into settlable matter.  The flow then passes through the Plastic Trickling Filter where the same process occurs. 

 Stage 4       The flow from the trickling filters then enters the Solids Contact Tanks  where a mass of microorganisms are concentrated.  Air is added to the tanks to provide mixing and oxygen for a stable environment.  Any remaining suspended waste is converted to a settlable material. 

 Stage 5       From the Solids Contact Tanks the flow proceeds to the Final Clarifiers  where the treated waste settles and is returned to the Contact Tanks  or the Primary Clarifiers  where it is removed from the system.  The remaining water of approximately 98% purity is discharged via pumps  into the Geneseo Creek or the Green River.

Stage 6       The solids that are removed from the system are pumped into the digesters  where anaerobic bacteria breakdown the solids.  After the solids are properly digested it can be either put on the Vacuum Assisted Beds and then spread on farmland or it can be pumped into the Sludge Hauler and injected into the farmland.