1055. reducing phosphorus discharges from neorsd wwtps. esping€¦ · brown and caldwell /neorsd...
TRANSCRIPT
Reducing Phosphorus Discharges from the NEORSD WWTPs
August 27, 2014
Greg Binder, P.E.Elizabeth Toot-LevyNortheast Ohio Regional Sewer District
Don Esping, P.E.Jeff Ifft , P.E.Brown and Caldwell
Agenda
Brown and Caldwell /NEORSD 2
• Phase 1 Evaluation Screening• Potential Future Phosphorus Limits• Phosphorus Reduction Alternatives
• Phase 2 Evaluation• Easterly, Westerly, Southerly Alternatives• Averaging Period Impacts
• Conclusions
• Who we are…• Regional wastewater utility created in 1972 by court order• Separate and distinct from the City of Cleveland and
Cuyahoga County
• What we do…• Servicing all or part of 62 member communities• 1 million customers• 90+ billion gallons wastewater treated each year
Northeast Ohio Regional Sewer District
Brown and Caldwell/NEORSD
Westerly WWTCEasterly WWTP Southerly WWTC
Northeast Ohio Regional Sewer District
4Brown and Caldwell/NEORSD
355square miles
Easterly and Westerly: Basis for TP Limit Scenarios
Brown and Caldwell /NEORSD
5
Easterly: 80/400 mgdWesterly: 30/100 mgd
• Lake Erie Discharges• Current Monthly TP Limit = 1.0 mg/L• Potential Monthly TP limit = range of 0.3 to 0.7 mg/L
Southerly: Basis for TP Limit Scenarios
Brown and Caldwell /NEORSD 6
Southerly: 120/615 mgd
• Cuyahoga River Discharge• Current Monthly TP Limit = 0.7 mg/L• Potential Monthly TP limit = as low as 0.3 mg /L
• Continued Ferric vs Bio-P
• Tertiary Processes
Phase 1 – Alternative Screening
Brown and Caldwell/NEORSD 7
DAFTBallasted FlocFilters
Phase 1 Screening
Brown and Caldwell /NEORSD 8
• Evaluate Options based upon a monthly TP limit• Chemical P Removal
Potential Effluent TP Limit(mg /L)
Easterly Westerly Southerly
EffluentFiltration
Ballasted Floc
EffluentFiltration
Ballasted Floc
EffluentFiltration
Ballasted Floc
TertiaryClarification /
Filtration
Ballasted Floc /
Filtration
0.50 √ √ √ √ √ √
0.30 √ √ √ √ √ √
0.15 √ √
• Facility sizing• Solids impact• Planning level costs
Basis of Evaluation
Brown and Caldwell /NEORSD 9
General Flow Scheme
Tertiary TreatmentFerric Chloride
Caustic
FinalEffluent
Secondary Effluent
Monthly Effluent TP Limit Target Effluent TP
0.5 mg/L ≈ 0.40 mg/L
0.3 mg/L ≈ 0.24 mg/L
0.15 mg/L ≈ 0.12 mg/L
Tertiary ProcessMax Month Effluent TP
Filtration 0.24 mg/L
Ballasted Flocculation 0.2 mg/L
Tertiary Clarifiers/Ballasted Flocculation with Filtration (Southerly)
0.1 mg/L
Easterly WWTP
0
0.5
1
1.5
2
2.5
3
3.5
4
4.501
‐Jan
‐10
01‐M
ar‐10
01‐M
ay‐10
01‐Jul‐10
01‐Sep
‐10
01‐Nov
‐10
01‐Jan
‐11
01‐M
ar‐11
01‐M
ay‐11
01‐Jul‐11
01‐Sep
‐11
01‐Nov
‐11
01‐Jan
‐12
01‐M
ar‐12
01‐M
ay‐12
01‐Jul‐12
01‐Sep
‐12
01‐Nov
‐12
01‐Jan
‐13
01‐M
ar‐13
Total Pho
spho
rus, m
g/L
Influent Effluent
Easterly: Historical Influent and Effluent P
Average Influent = 2.0 mg/L= 1415 lb P/d
Easterly – Tertiary Treatment Facility and Impacts
Brown and Caldwell /NEORSD 12
Scenario Tertiary Capacity
mgdAdditional
FeCl3mg/L
Caustic Addition
gal/d
Solids IncreasePercent
Filtration
0.5 mg/L TP 55 5 40 +4
0.3 mg/L TP 200 5 100 +7
Ballasted Flocculation
0.5 mg/L TP 50 30 200 +9
0.3 mg/L TP 110 30 400 +17
“Optimized” Operation as Higher Ferric Dosage
-- 5 100 +4
“Optimized” Operation for Lower TP limit
Brown and Caldwell /NEORSD
Easterly - 0.5 mg/L TP Limit - Filters
Brown and Caldwell /NEORSD 14
To Lake Erie
Dry Weather Flow to Filters
Filters5 or 6 @ 40’x60’
Chemical Storage
and Handling
6 5
4 3
2 1
5 6
3 4
1 2
Pump Station
Additional Chemical Storage
Westerly WWTP
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
01
-Jan
-10
01
-Feb
-10
01
-Mar
-10
01
-Apr
-10
01
-May
-10
01
-Jun
-10
01
-Jul
-10
01
-Aug
-10
01
-Sep
-10
01
-Oct
-10
01
-Nov
-10
01
-Dec
-10
01
-Jan
-11
01
-Feb
-11
01
-Mar
-11
01
-Apr
-11
01
-May
-11
01
-Jun
-11
01
-Jul
-11
01
-Aug
-11
01
-Sep
-11
01
-Oct
-11
01
-Nov
-11
01
-Dec
-11
01
-Jan
-12
01
-Feb
-12
01
-Mar
-12
01
-Apr
-12
01
-May
-12
01
-Jun
-12
01
-Jul
-12
01
-Aug
-12
01
-Sep
-12
01
-Oct
-12
01
-Nov
-12
01
-Dec
-12
01
-Jan
-13
01
-Feb
-13
01
-Mar
-13
Tota
l Pho
spho
rus,
mg/
L
Influent Effluent
Westerly: Historical Influent and Effluent PAverage Influent = 1.9 mg P/L
= 430 lb P/d
Westerly -Tertiary Treatment Facility and Impacts
Brown and Caldwell /NEORSD 17
Scenario TertiaryCapacity
mgd
Additional FeCl3mg/L
Caustic Addition
gal/d
Solids IncreasePercent
Sludge Fe ContentPercent
Existing Ops -- 7 0 -- 1.7
Filtration
0.5 mg/L TP 21 7 5 4 2.8
0.3 mg/L TP 70 7 15 5 3.1
Ballasted Flocculation
0.5 mg/L TP 19 30 30 9 5.3
0.3 mg/L TP 45 30 60 14 6.7
Southerly WWTC
• Historical data not applicable with decommissioning Zimpro and secondary treatment modifications
• Estimate plant performance using BioWin®
Southerly - Approach
Brown and Caldwell /NEORSD 19
Southerly – Predicted Secondary Effluent without Fe
Brown and Caldwell /NEORSD 20
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0 10 20 30 40 50 60
SSAS
Efflue
nt TP, m
g/L
Model DayPredicted SSAS Effluent‐ Medium Range Predicted Monthly Discharge‐Medium Range
Predicted SSAS Effluent ‐ Upper Range Predicted Monthly Discharge‐Upper Range
Southerly– Filter Concept Footprint
Brown and Caldwell /NEORSD 21
30-day Average TP Permit Limit
(mg/L)
Capacity(mgd)
Number of Filters
0.50 130 13
0.30 250 20
0.15 225 20
28 existing
Normalized Costs for Further TP Reduction
22
$-
$100
$200
$300
$400
$500
$600
An
nu
aliz
ed $
/lb
TP re
mov
ed
Capital O&MFilters Ballasted Floc
Impact of Averaging Period- Filter Options
Brown and Caldwell /NEORSD 23
Plant/Averaging Period
0.5 mg/L TP 0.3 mg/L TPTertiary Capacity
(mgd)Tertiary Capacity
(mgd)Easterly
30 Day Average 55 200
90 Day Average 47 150
180 Day Average 43 140
Westerly
30 Day Average 21 70
90 Day Average 18 45
180 Day Average 15 33
Conclusions
Brown and Caldwell /NEORSD 24
Easterly and Westerly
Southerly• ≈ 65% itinerary average flow to achieve 0.5 mg/L TP• ≈ 90% of itinerary peak week flow treated to achieve 0.3 mg/L TP
Averaging periods can significantly reduce facility needs and costs
Item Filters Ballasted Floc
0.5 mg/L TP ≈ 65% Daily flow ≈ 60% Daily flow
0.3 mg/L TP ≈ 90% Peak week flow ≈ 55% Peak week flow
Solids Production Increase
5%– 10% 10% –20 %
Sludge Iron Content 0.5 – 1.0% pts 4-6 pts