Wastewater Treatment Facility Tour

Introduction

• Speaker: Ryan Gifford, Wastewater Superintendent, Wisconsin Rapids Wastewater Department
• Purpose: Virtual tour of the facility and its processes for public education.

Wastewater Collection

• Sewage from homes flows into underground pipes, directed towards the facility through lift stations.
• Lift stations pump sewage to the headworks building.

Treatment Processes

Headworks Building

• Wastewater undergoes initial treatments:
  • Bar Screen: Removes rags and inorganic material.
  • Grit Chamber: Settles out heavy materials like sand and rocks.

Primary Clarifier

• Function: Allows wastewater to slow down, permitting heavy solids to settle.
• Duration: Wastewater spends 2-5 hours here.
• Removes approximately 30% of Total Suspended Solids (TSS) and Biochemical Oxygen Demand (BOD).
• Two primary clarifiers provide redundancy for maintenance.

MBBR (Moving Bed Biofilm Reactor)

• Process: Treats primary effluent with microorganisms consuming soluble BOD, nitrogen, and phosphorus.
• Aeration: Dissolved oxygen is monitored and adjusted via blowers.
• This process removes 99% of BOD and is more efficient than conventional systems.

Secondary Treatment

• Activated Sludge Process: Further stabilizes wastewater and ensures removal of nitrogen, phosphorus, and BOD.
• Duration: Wastewater spends 3-5 hours in aeration basins.

Final Clarifiers

• Purpose: Settles out microbes after treatment; the clear water flows to disinfection.
• Two final clarifiers allow for adjustments based on hydraulic incidents.

Disinfection Process

• UV Disinfection System: Active May 1 - October 31; uses UV bulbs to kill remaining bacteria.
• Monitored for water clarity; adjusts power based on transmittance.

Anaerobic Digesters

• Types: Two thermophilic digesters (heated to 131°F) and one mesophilic digester (heated to 98°F).
• Function: Reduce volatile organic solids by 40-70% and produce methane gas.
• Methane is used for generating power (CHP) and heating digesters.
• Class A Product: Digested solids can be used as fertilizer due to the T-PAD process.

Solids Treatment

• Fan Press: Thickens and dewaters sludge.
• Rotating Drum Thickeners: Removes clear water from waste activated sludge, concentrating solids.

Combined Heat and Power (CHP) Generator

• Capacity: 330 kW generator powered by methane.
• Provides approximately 62% of the facility’s power needs.

Laboratory Operations

• Key Tests Conducted:
  • Biochemical Oxygen Demand (BOD): Monitored daily.
  • pH Testing: Ensures neutrality.
  • Total Suspended Solids (TSS): Monitored regularly.
  • Total Phosphorus: Critical for nutrient monitoring.

Collection System Maintenance

• Vac Trucks: Maintain sewer lines, clean pipes, and handle stormwater catch basins.
• Televising Rig: Inspects underground pipes for damage or blockages.
• Inflow and Infiltration (I/I) Issues: Focus on preventing clear water from entering the sanitary sewer system.

Awards and Recognition

• Operations Award: Recognizing improvements in the facility.
• Laboratory Excellence Award: Acknowledges outstanding lab management and data accuracy.
• Project of the Year Award: For new force main project, emphasizing collaboration and environmental protection.

Conclusion

• Importance of community awareness regarding wastewater treatment and responsible sewer usage.
• Appreciation for staff efforts and commitment to environmental protection.