James Winslade Instructor, Environmental Resources Training Center Southern Illinois University-Edwardsville
In Memory of Steven Fiepke Chief Operator Village of Algonquin WWTP Skilled in Operation Dedicated to his Craft Dedicated to sharing his knowledge with others Passed Away 12/18/11
Purpose and Method What Nutrient Removal Processes are in use at this time in Illinois? How widespread is the practice of nutrient removal? Information gathered through a survey of wastewater operations staff by personal contact and through the help of Operator groups in several locations in the state Not able to contact all plants.
Some History Concern with phosphorus dates back to 1970 s and concern with eutrophication in the Great Lakes. Phosphates removed from laundry detergents. Concerns with nutrient discharge to Chesapeake Bay Hypoxic Zone in the Gulf of New Mexico Concerns with Mississippi River Basin Local Environmental Group Involvement
The Present Majority of plants within the state are not required at this time to limit discharge of total nitrogen and phosphorus Phosphorus limitation of 1 mg/l for major discharges and areas where receiving stream is considered impaired for phosphorus downstream Permits requiring monitoring of total nitrogen and total phosphorus in effluent
Ammonia-the initial focus Plants required to limit discharge of ammonia in effluent on a seasonal basis (April-October) Effluent ammonia limits lower during warmer period of the year due to increased nitrification potential in receiving streams Processes involved include activated sludge process control modifications to insure nitrification Increase MCRT Operate in Extended Aeration Mode Several processes involve separate facilities for nitrification Bio-Towers, RBC s
Oxidation Ditch-Extended Aeration Troy, Illinois- example Operated in Extended Aeration Mode Maintain MCRT sufficient to maintain nitrification
Bloomington-Normal Bio-Towers following Trickling Filters
Urbana-Champaign Sanitary District High Rate Trickling Filters Follow Activated Sludge System which provides Secondary Treatment for CBOD Removal and Phosphorus Removal
Peoria, Illinois RBCs RBCs for nitrification 68 Shafts Follow Activated Sludge System
Next Focus Phosphorus Physical-Chemical Processes Chemical addition for precipitation of phosphorus and removal from the effluent by clarification and/or filtration used by many systems in state. Normally does not require major facility modifications Installed in several BNR facilities for polishing and backup to the biological system
Chemical Phosphorus Removal Chemicals Used Alum, Ferric Chloride, Sodium Aluminate, Poly Aluminum Chloride, Lime May be dosed at multiple points in system Clarification and Filtration important
Clarification and Filtration Clarification and Filtration instrumental in meeting phosphorus limits for both biological and chemical processes Improper clarifier operation may adversely affect phosphorus removal Multiple filter types in use
Next Focus-Biological Nutrient Removal Processes Processes may be used for removal of nitrogen or phosphorus alone or as a combined system Utilize either separate zones or cycles to establish conditions for removal of nitrogen and/or phosphorus removal Zones include anaerobic (no DO and no nitrate), anoxic (low DO and nitrate), and oxic or aerated Often include control by on-line process instrumentation
Multi-channel Oxidation Ditch City of Robinson, East Dundee, Highland, Lake of the Hills, Rochelle Outer Channel forms anoxic zone for denitrification and may aid in phosphorus removal May be configured for nitrate recycle Utilize ORP and DO probes for DO control
A/O or Phoredox Urbana Champaign Sanitary District Anaerobic Zone ahead of Aerobic zone Return of RAS to anaerobic tank Effluent TP 0.5 mg/l
A2/O, Pho-redox City of Plano Anaerobic, anoxic, and aerobic basins Nitrate recycle to anoxic zone RAS to anaerobic Zone Eff TP 0.7 to 0.9 mg/l
Counter Current Aeration-Schreiber Continuously Sequencing Reactor DuQuoin, Marion, Chester, Anna, Belleville under construction Operating cycle Aeration on 60 min. Aeration off 180 min. Traveling bridge provides mixing to tank
Counter Current Aeration DuQuoin Performance Ammonia 0.04 to 0.05 mg/l Eff TP 0.4 to 0.5 mg/l Eff TSS 1.0 to 1.5 mg/l Eff BOD 1.0 to 1.5 mg/l Flow 1.5 MGD
Sequencing Batch Reactor Waterloo, Caseyville Township, Marisa Insert anoxic fill and/or anoxic mix fill into cycle program for denitrification
Biolac Roxana In Start-up Aerated lagoon Alternating control of aeration headers aerated/anoxic
Vertical Loop Reactor (Siemens) Lake of the Hills Operates as anaerobic zone preceding multichannel oxidation ditch RAS returns to head of VLR Operates at -300 ORP
Vertical Loop Reactor Performance NH3 0.1 mg/l Inf TP 7 to 12 mg/l Eff TP 0.1 mg/l Flow 3.3 MGD Multiple VLRs being installed for Springfield
5 Stage Bardenpho - Algonquin 5 Basins-Anaerobic, Anoxic, Aeration, Anoxic, Short Term Aeration Anaerobic-mixers turned off periodically to enhance anaerobic conditions Nitrate recycle to 1 st Anoxic Basin
5 Stage Bardenpho 2 nd Anoxic basin equipped for methanol feed but not used at this time Maintain sludge blanket in primary clarifiers to develop VFA s for phosphorus removal in anaerobic zone
5 Stage Bardenpho Performance 2010 2011 CBOD - <2 mg/l NH3 -.06 to.18 mg/l Total P -.039 to 1.08 mg/l TSS 3 to 9 mg/l Total N 3.49 to 5.43 mg/l Flow 3.5 MGD
Control System Technology Several systems in state use combination of on line sensors for control of aeration and mixing Combination of ORP probes and Dissolved Oxygen Probes may be used in conjunction with computer program or stand alone
In Summary Variety of Processes in use Biological processes utilize various designs to develop anaerobic, anoxic, and aerated zones or cycles Overall results are positive not only for nutrients, but for overall plant operation I want to extend my thanks to all who provided information and material for use in this presentation Questions?