Practical Solutions for Combined Sewer Overflow Control Engineering Healthy Waterways
PROCESS OVERVIEW 4 LEVELS OF TREATMENT 1. Screening (Coarse Screening (>1 MM), Fine Screening (<.15 MM) 2. Storage With Treatment at a Central Facility (Basins or Tunnels) 3. Remote Treatment (SanSep, High Rate Treatment such as Actiflo or DensiDeg) 4. Remote Storage and Treatment (Treatment Shaft)
GROSS SCREENING FLOATABLES, TRASH & DEBRIS >4 mm SUSPENDED SOLIDS 20% NUTRIENTS DISINFECTION - CHEMICAL - UV minimal Yes Doubtful
COARSE SCREENING PERFORATED PLATES BAND, STEP, STATIC, CYCLONE RAKED BAR SOLIDS CAPTURE, SOLIDS PASS-ON RAKE AND COMB, BRUSH NETTING SYSTEMS FLOATSEP
Raked Bar Screen - Installed Horizontally for Efficiency - Electro-Polished Stainless Steel -Modular Construction -Can Operate Completely Submerged
RAKED BAR SCREEN
Profile thru Raked Bar Screen (One Module) 1290 Void 50 Section 100 Section 50 Void Direction of Flow Direction of Flow Flow rises from the foul sewer and passes through the screen bars, the void sections on the screen creates turbulence as the flow rises and hits the blanking plates which run the width of the screen. This ensures the screenings are not compacted and are passed onto the wastewater treatment works for the screenings removal.
Cyclone Screen
CYCLONE INSTALLATION
FloatSep
HOW IT WORKS In a typical overflow structure, floating solids, oils and scum are discharge though the overflow weir Side baffles can retain floating material in the overflow chamber until the baffle is overtopped FloatSep uses a pair of baffles to induce a vortex to keep floating material moving down the sewer
Before Installation
BEFORE INSTALLATION
AFTER INSTALLATION
After Installation
WHAT CAN IT DO?
WHAT CAN IT DO?
FINE SCREENING FLOATABLES, TRASH & DEBRIS >.10 mm (.004 in) SUSPENDED SOLIDS 40-80% NUTRIENTS 30 40% DISINFECTION - CHEMICAL - UV Yes Yes
SanSep Gross Solids Separator (Continuous Deflective Separation ) access hatch inlet separation chamber outlet riser separation screen sump basket - optionally
SANSEP TECHNOLOGY BASIS Strong washing effect of incoming fluid keeps screen free of pollutants Conventional devices rely on direct screening - screens become blocked Direct screening - solids become caught on screen Indirect screening - solids swept past screen
SANSEP PEFORMANCE LOUISVILLE
SANSEP PERFORMANCE LOUISVILLE
CDS PERFORMANCE SOLIDS CHARACTERIZATION WET WEIGHT 2638 LB DRY WEIGHT 1000 LB 37.9% dry solids TRASH 35 LB 3.5 % ORGANIC 724 LB 72.4 % INORGANIC 241 LB 24.1 %
UV DISINFECTION PILOT TESTS
REMOTE STORAGE Near Surface Open Air Basins Near Surface Covered Basins Deep Tunnels
Near Surface Open Air Basins Least Expensive Storage Alternative May Generate Odors Very Large Footprint Require Cleaning After Every Event Easy Construction
NEAR SURFACE COVERED BASINS Can Be Expensive to Construct Very Large Footprint Require Cleaning After Every Event Fairly Easy Construction
DEEP TUNNELS Very Expensive Low Surface Footprint Complicated Construction Long Term Cleaning Problems
HIGH RATE CEPT (REMOTE TREATMENT) ACTIFLO DENSADEG MIXING W/ LAMELLA CLARIFIERS PWTech FINE SOLIDS SEPARATION (FSS)
CHEMICALLY ENHANCED PRIMARY CLARIFICATION FLOATABLES, TRASH & DEBRIS 100% SUSPENDED SOLIDS 95-99% NUTRIENTS BOD - PHOSPHORUS (Total) - TKN DISINFECTION - CHEMICAL - UV 50 70% 85 95% 30 40% Yes Yes
STORAGE WITH TREATMENT at a REMOTE SITE Deep Shaft Storage and Treatment
Innovative Vertical Treatment Shaft Process (Dry Weather Flow - Shaft Empty) Raked Bar Screen U.S. Patent No. 6503404/ Additional Patents Pending
WET WEATHER FLOW THROUGH CONDITION U.S. Patent No. 6503404/ Additional Patents Pending Pat. 6,503,404
POLLUTANT REMOVAL TSS 47 percent BOD 69 percent Ammonia Nitrogen 40 percent Phosphorus 25 percent
DEEP SHAFT FACILITY CSO 16 Shaft - Project Completion
QUESTIONS / DISCUSSION