weao sdc 2015 nutrient recovery at the ashbridges bay wastewater treatment plant tania farah amal...
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WEAO SDC 2015
Nutrient recovery at the ashbridges bay wastewater
treatment plant
Tania Farah Amal Ghamrawi
David TranRose Zhao
Ashbridges Bay wASTEwater Treatment Plant
ABTP Fast Facts
Location City of Toronto
Effluent Discharge
Lake Ontario
Nominal Capacity
818 MLD
Equivalent Population
1,524,000
Sewershed Area Serving
25,000 ha
ECA Effluent Discharge Limits
Parameter Limit
SS [mg/L] 25
SS Loading Rate (kg/day)
20,450
CBOD5 [mg/L] 25
CBOD5 (kg/day) 20,450
pH 6 – 8.5
TP [mg/L] 1
TP Loading Rate (kg/day)
818
E-Coli [CFU/100 mL] 200
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Toronto Water Strategic Plan
Mission Statement
Provide quality water services to the Toronto community while protecting public health, safety and property in an environmentally and a fiscally responsible manner
Guiding Principles
I. Continuous Service Delivery Improvement
II. Financial Vitality, Viability and Sustainability
III. Operational Excellence
IV. Infrastructure Management
V. Employer of Choice
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ABTP Current initiatives
Water Quality Improvement
Process changes to encourage nitrification Increased SRT and DO
concentrations
Improved DO control instrumentation programming
Additional 10 million kWh is used per
year
Resource Recovery Initiatives
Recycling of effluent water for non-potable use
Use of digester gas for process and building heat
Beneficial use of biosolids
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Objective of Project
Reduce the TKN and ammonia of the centrate streams to approaching plant influent levels.
Two additional areas in which the plant could adopt a resource recovery approach to:
Benefit the operations Lessen the
environmental impact Reduce the cost of
treatment
PHASE I PHASE II
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PHASE I Planned approach
Centrate Treatment Options
Resource Recovery
Treatment
Struvite Recovery
Ammonia Stripping
Ion Exchange
Phase I-1
Phase I-2
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Centrate Characteristics
Centrate Characteristics
Parameter Value
Nominal Centrate Flow (L/s)
84(8 MLD)
TKN (mg/L) 907
Ammonia (mg/L) 590
Phosphorous (mg/L) 139
TSS (mg/L) 1959
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Nutrient Recovery Options
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Struvite Recovery options
Factor DHV Crystalacto
r®
Multiform Harvest
Inc. Crystallize
r
NuReSys®
Process
Ostara Pearl® Process
PacquesPHOSPHAQ
™
Country 5 0 10 0 10 0
Reactor Type
5 10 10 0 10 0
Chemicals Used
10 0 10 10 10 0
HRT 15 10 10 8 10 0
P Reduction
15 10 8 0 8 7
NH3-N Reduction
15 10 0 0 10 10
Full Scale Plants
5 3 0 8 10 2
Odour Control
10 10 10 0 10 0
Capital Costs
20 7 5 9 0 10
TOTAL 100 755 670 440 770 465
oSTARA PEARL® PROCESSMg+2 + NH4
+ + PO43- + 6H2O MgNH4PO46
H2OThe OSTARA Advantage Up to 94% PO4
3- and 30% NH3 removal efficiencies Canadian 8 Full Scale Municipal InstallationsRenewable fertilizer production Reduces:
Chemical use Nutrient loads Operation and maintenance costs Greenhouse gas emissions
Process Requirements
MgCl2 6000 kg/day
NaOH 800 kg/day
Heat 16 GJ/day
Power 2350 kWh/day
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Ostara
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OSTARA PEARL® PROCESS
Waste Activated Sludge StrippingTo Remove Internal Phosphorous
Improved biosolids cake
4% increase in solid content
20% decrease in volume
25% Influent P
20% Influent P
Ostara
EXPECTED EFFLUENT CHARACTERISITCS
Centrate
Flow (m3/d) 7273
TSS (mg/L) 1959
PO4-P (mg/L)
139
NH3-N (mg/L)
590
TKN (mg/L) 907
WASSTRIP®
Flow (m3/d) 3391
TSS (mg/L) 500
PO4-P (mg/L)
374
NH3-N (mg/L)
30
Pearl® Effluent
Flow (m3/d)
10665
TSS (mg/L)
1495
PO4-P (mg/L)
34
NH3-N (mg/L)
331
TKN (mg/L)
547
Objective
Influent
Centrate
Ammonia (mg/L)
25.4 590
TKN (mg/L) 50.9 907
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Ostara
Nutrient removal
Centrate Treatment Options
Resource Recovery
Biological Treatment
Nitrification-Denitrification
Nitritation-Denitritation
Partial Nitritation-Anammox
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Biological Treatment of Nitrogen
Biological
Nitrification-Denitrification
Nitritation-Denitritation
Partial N-Anammox
1 mole Nitrate
1 mole Nitrite 1 mole Nitrite
1 mole Ammonia ½ mole Nitrogen Gas
25% O2
75% O2
40% C
60% C
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Biological Treatment of nitrogen
1 mole Nitrate
1 mole Nitrite 1 mole Nitrite
1 mole Ammonia ½ mole Nitrogen Gas
25% O2
40% C
60% C
Biological
Nitrification-Denitrification
Nitritation-Denitritation
Partial N-Anammox
75% O2
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Partial N-Anammox
Biological Treatment of nitrogen
1 mole Nitrate
½ mole Nitrite 1 mole Nitrite
1 mole Ammonia ½ mole Nitrogen Gas
25% O2
40% C
60% C
Biological
Nitrification-Denitrification
Nitritation-Denitritation 40% O2
75% O2
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Partial Nitritation-Anammox Processes
Partial Nitritation-Anammox
DEMON® SBR
ANITATM Mox MBBR
2-Stage SHARON®-ANAMMOX®
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Partial Nitritation-Anammox Processes
DEMON® SBR
ANITATM Mox
SHARON®-ANAMMOX®
TN Removal (%)
85 80 90
Energy (kW-h kg-1)
1.0-1.3 1.45-1.75 4.17
Start-Up Time (Months)
2-5 3-4 3-5
Operator Attention
High Low Low
Maintenance
High Low Medium 18
Preliminary Reactor Characteristics
Soluble BOD Removal
ANITATM Mox
Nitrification
Volume 1200 m3 3500 m3 900 m3
SWD 5.0 m 5.0 m 5.0 m
Air Flow Requirement
6500 Nm3/h14000 Nm3/h
5000 Nm3/h
Effluent NH4-N
441 mg/L 72 mg/L 30 mg/L
Effluent TKN -- 157 mg/L 111 mg/L
Effluent TSS -- -- 1500 mg/L
Alkalinity Consumption
-- 1600 mg/L 300 mg/L19
Dissolved Air Flotation Unit
Effluent TKN 40-50 mg/L
Design BASIS
Reduce Cost and Energy
Lessen Environmental
Impact
Improving Operations
Resource Recovery
• TN removal in addition to ammonia removal
• Improved final effluent
• TN removal in addition to ammonia removal
• Improved final effluent
• Ferric chloride eliminated
• Coarse to fine diffusers
• Ferric chloride eliminated
• Coarse to fine diffusers
• Non-chemical sludge• Less sludge volume • Safer to use on land
• Non-chemical sludge• Less sludge volume • Safer to use on land
• Requirement for: • Struvite Recovery
• Requirement for: • Struvite Recovery
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PROCESS SELECTED: A2O
Anaerobic
Anoxic
Aerobic Second
ary Clarifier
Influent
VFA WAS
RAS
NMLR
Secondary Effluent
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DESIGN SPECIFICATION
ANAEROBIC
ANOXIC
AEROBIC
25.4%
25.4%
49.2%
1.5 h
1.5 h
2.9 h
Aeration Tanks
Parameter
Value
Total Volume
201,902 m3
Total HRT 5.9 h
RAS 490,800 m3/d
MLSS 3,000 mg/L
Loading
Current A2O
TKN 9.72 mg/L
1.0 mg/L
Ammonia
7.72mg/L < 1.0 mg/L
TN 25 -30 mg/L
10 mg/L 22
ANITATM Mox Overall Benefits
Overall project scope: ≈ $20-25 million
Service Life: >20 years
No additional chemicals
No carbon source
pH is self-regulated DO is automatically adjusted
No heavy maintenance
Simple operation
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Ostara Overall benefits
Capital Cost of Ostara:$20 million Includes 2 Pearl®
10000 Reactors, a building and WASSTRIP® Tank
Expected Annual Savings: $5 million
Expected Payback Period: 4-6 years
Ostara Savings
Ferric Chloride Elimination
$1,259,000
WAS Thickening Polymer
$138,000
Biosolids Dewatering Polymer
$775,000
Sludge Handling and Disposal
$2,467,000
N Removal $317,00ABTP Expected
Production: 15.2 tonnes/day Crystal Green® Fertilizer WERF,
2014
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Ostara
A2/O Overall Benefits
Estimated Annual Savings: $3.6 million
Savings not quantified: switching from coarse to fine air bubble diffusers
A2O Savings
Ferric Chloride Elimination
$1,259,000
WAS Thickening Polymer $238,000
Biosolids Dewatering Polymer
$500,000
Sludge Handling and Disposal
$1,592,000
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Updated Schematic of ABTP
Phase I-1
Phase I-2
Phase II
Acknowledgements
Dr. Rajesh SethUniversity of WindsorAssociate Professor
Department of Civil and Environmental Engineering
Faculty Advisor
Dr. Edwin TamUniversity of WindsorAssociate Professor
Department of Civil and Environmental Engineering
Faculty Advisor
Sailesh SinghGolder Associates
Water Treatment EngineerIndustry Advisor
Michael ReaumeStantec Consulting Engineer in Training
Industry Advisor
Derek LyckeOstara Nutrient Recovery
Technologies Technical Director, Nutrient
Recovery Solutions
David PearceVeolia Water Technologies
Sales Director
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