Refinement of Nitrogen Removal from Municipal Wastewater Treatment - - PowerPoint PPT Presentation

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Refinement of Nitrogen Removal from Municipal Wastewater Treatment - - PowerPoint PPT Presentation

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Refinement of Nitrogen Removal from Municipal Wastewater Treatment Plants Prepared for Maryland Department of the Environment Presented by: Gannett Fleming, Inc. Stephen B. Gerlach, PE & Carrie DeSimone In partnership with George Miles

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SLIDE 1

Prepared for

Maryland Department of the Environment

Refinement of Nitrogen Removal from Municipal Wastewater Treatment Plants

Presented by:

Gannett Fleming, Inc.

Stephen B. Gerlach, PE & Carrie DeSimone

In partnership with George Miles Buhr, LLC

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SLIDE 2

What is ENR? What is ENR? What is ENR? What is ENR?

  • Enhanced Nutrient Removal

Enhanced Nutrient Removal Enhanced Nutrient Removal Enhanced Nutrient Removal

  • Reduce nutrient discharges from

Reduce nutrient discharges from Reduce nutrient discharges from Reduce nutrient discharges from WWTPs WWTPs WWTPs WWTPs

  • Use of state

Use of state Use of state Use of state-

  • of
  • f
  • f
  • f-
  • the

the the the-

  • art microbial technology to break

art microbial technology to break art microbial technology to break art microbial technology to break down nitrogen before discharge down nitrogen before discharge down nitrogen before discharge down nitrogen before discharge

  • Next step from BNR

Next step from BNR Next step from BNR Next step from BNR

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SLIDE 3

Biological Nutrient Removal Program Biological Nutrient Removal Program Biological Nutrient Removal Program Biological Nutrient Removal Program (BNR Program) (BNR Program) (BNR Program) (BNR Program)

  • Implemented in 1983 by the Maryland Department of

Implemented in 1983 by the Maryland Department of Implemented in 1983 by the Maryland Department of Implemented in 1983 by the Maryland Department of the Environment (MDE) the Environment (MDE) the Environment (MDE) the Environment (MDE)

  • Included 66 plants of capacity

Included 66 plants of capacity ≥ 0.5 MGD 0.5 MGD Included 66 plants of capacity Included 66 plants of capacity ≥ 0.5 MGD 0.5 MGD

  • Plants retrofitted to achieve total nitrogen limits of 8 mg/l

Plants retrofitted to achieve total nitrogen limits of 8 mg/l Plants retrofitted to achieve total nitrogen limits of 8 mg/l Plants retrofitted to achieve total nitrogen limits of 8 mg/l

  • Goal was 40% reduction of nutrients to Chesapeake Bay

Goal was 40% reduction of nutrients to Chesapeake Bay Goal was 40% reduction of nutrients to Chesapeake Bay Goal was 40% reduction of nutrients to Chesapeake Bay (Bay) (Bay) (Bay) (Bay)

  • Have exceeded this goal

Have exceeded this goal Have exceeded this goal Have exceeded this goal

  • Actual reductions from 1985 levels=16.9 million pounds

Actual reductions from 1985 levels=16.9 million pounds Actual reductions from 1985 levels=16.9 million pounds Actual reductions from 1985 levels=16.9 million pounds

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SLIDE 4

Purpose of Enhanced Nutrient Removal Study Purpose of Enhanced Nutrient Removal Study Purpose of Enhanced Nutrient Removal Study Purpose of Enhanced Nutrient Removal Study (ENR Study (ENR Study (ENR Study (ENR Study – – 2002 2002 2002 2002 – – 2004) 2004) 2004) 2004)

  • Clea

Clear evidence p r evidence plants could exceed 8 mg/l ants could exceed 8 mg/l Clea Clear evidence p r evidence plants could exceed 8 mg/l ants could exceed 8 mg/l

  • EPA/

EPA/MDE/ MDE/Loc Local Go l Gove vernments looking to rnments looking to achie achieve further nitro e further nitrogen en EPA/ EPA/MDE/ MDE/Loc Local Go l Gove vernments looking to rnments looking to achie achieve further nitro e further nitrogen en reductions cost effectively reductions cost effectively reductions cost effectively reductions cost effectively

  • Enhancement of BNR Program in c

Enhancement of BNR Program in compliance with amended 200 mpliance with amended 2000 Enhancement of BNR Program in c Enhancement of BNR Program in compliance with amended 200 mpliance with amended 2000 Chesapeake Bay Agr Chesapeake Bay Agreement by furt ement by further reducing nutrients to the Ba her reducing nutrients to the Ba Chesapeake Bay Agr Chesapeake Bay Agreement by furt ement by further reducing nutrients to the Ba her reducing nutrients to the Bay y

  • GF/GMB asked to evalua

GF/GMB asked to evaluate 20 of the larg te 20 of the largest est GF/GMB asked to evaluate 20 of the larg GF/GMB asked to evaluate 20 of the largest est WWTPs WWTPs WWTPs WWTPs in MD in MD in MD in MD

  • Ev

Evalua aluate alternative te alternatives for re for redu ducing nitrogen in WWTP effluent cing nitrogen in WWTP effluent Ev Evalua aluate alternative te alternatives for re for redu ducing nitrogen in WWTP effluent cing nitrogen in WWTP effluent

  • Develop c

Develop cost estimate for alternatives estimate for alternatives Develop c Develop cost estimate for alternatives estimate for alternatives

  • Extrap

Extrapolate cost estimate to 6

  • late cost estimate to 66 plants in BNR Program which

plants in BNR Program which Extrap Extrapolate cost estimate to 6

  • late cost estimate to 66 plants in BNR Program which

plants in BNR Program which helped establish newly enacted flush tax helped establish newly enacted flush tax helped establish newly enacted flush tax helped establish newly enacted flush tax

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SLIDE 5

Cumberland WWTP Conococheague WWTP

Hagerstown WPCP

Westminster WWTP City of Frederick WWTP

Ballenger Creek WWTP Seneca WWTP

Freedom District WWTP Back River WWTP

Cox Creek WRF

Sod Run WWTP

Annapolis WRF

Hurlock WWTP

City of Cambridge WWTP

Salisbury WWTP Parkway WWTP Bowie WWTP

Little Patuxent WRF

Piscataway WWTP

Marley Taylor WRF

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SLIDE 6

Current Process Current Process Current Process Current Process

Cambridge MLE 8.1 Seneca MLE 20 Piscataway Step Feed 30 Parkway Bardenpho (4-Stage) 7.5 Annapolis Bardenpho (4-Stage) 13 Ballenger A2O 6 Marley-Taylor Schreiber System 6 Freedom District MLE 3.5

  • L. Patuxent

Johannesburg 22.5 Cumberland Step Feed 15 Sod Run A2O Modified 20 Westminster MLE/A2O 5 Hagerstown Modified Johannesburg 8 Conococheague MLE 4.1 Frederick A2O 7 Bowie VT2 3.3 Cox Creek MLE 15 Back River MLE 180 Salisbury Submerged (A2O) Trickling Filter 8.5 Hurlock Bardenpho (4-Stage) 1.65 RATED FLOW (MGD) PLANT EXISTING BNR PROCESS

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SLIDE 7

Phase I Phase I Phase I Phase I Approach Approach Approach Approach

  • Phase I (20

Phase I (2002 Phase I (20 Phase I (2002-

  • 2003):

2003): 2003): 2003): Evaluate ways to cost

Evaluate ways to cost effectively reduce N in effectively reduce N in Evaluate ways to cost effectively reduce N in Evaluate ways to cost effectively reduce N in plant discharges plant discharges plant discharges plant discharges

  • Primary considerations in developing alternatives

Primary considerations in developing alternatives Primary considerations in developing alternatives Primary considerations in developing alternatives

  • developed biological models at ea

developed biological models at each facility to estimate nitroge ch facility to estimate nitroge developed biological models at ea developed biological models at each facility to estimate nitroge ch facility to estimate nitrogen n n n remov removal capacity l capacity remov removal capacity l capacity

  • determined tank (reactor) volume

determined tank (reactor) volume requirem requirements ents for each plant uti for each plant uti determined tank (reactor) volume determined tank (reactor) volume requirem requirements ents for each plant uti for each plant utilizing lizing lizing lizing industry s industry standards andards and and individual plant data individual plant data industry s industry standards andards and and individual plant data individual plant data

  • site constraints

site constraints site constraints site constraints

  • existing plant configuration

existing plant configuration existing plant configuration existing plant configuration

  • cost effectivene

cost effectiveness of alternatives ss of alternatives cost effectivene cost effectiveness of alternatives ss of alternatives

  • Needed one or two processes that were proven and reliable

Needed one or two processes that were proven and reliable Needed one or two processes that were proven and reliable Needed one or two processes that were proven and reliable

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SLIDE 8

Breakdown of BNR Processes in Maryland Phase I Challenge

25% 6% 15% 6% 1% 6% 1% 3% 1% 7% 3% 6% 6% 1% 3% 1% 1% 1% 3%

MLE

A2O Activated Sludge Methanol Addition Oxidation Ditch Overland Lagoon Schreiber Bardenpho RBC Trickling Filter Step Feed

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SLIDE 9

Biological Nitrogen Removal Biological Nitrogen Removal Biological Nitrogen Removal Biological Nitrogen Removal Nitrogen Cycle Nitrogen Cycle Nitrogen Cycle Nitrogen Cycle ENR process takes ENR process takes additional time and additional time and requires additional tank requires additional tank volume beyond BNR. volume beyond BNR.

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SLIDE 10

Modified Modified Modified Modified Ludzack Ludzack Ludzack Ludzack-

  • Ettinger

Ettinger Ettinger Ettinger (MLE Process) (MLE Process) (MLE Process) (MLE Process)

Anoxic Oxic Clarifier Internal Recycle RAS

Cox Creek WRF, Anne Arundel Co. 15 mgd

WAS

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SLIDE 11

A A2

2O Process

O Process O Process O Process

Anoxic Anaerobic Oxic Internal Recycle Clarifier RAS

Sod Run WWTP, Harford Co. 20 mgd

WAS

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SLIDE 12

Bardenpho Bardenpho Bardenpho Bardenpho Process Process Process Process

  • Demonstrated ability

Demonstrated ability to to Demonstrated ability Demonstrated ability to to achieve 3 mg/l achieve 3 mg/l achieve 3 mg/l achieve 3 mg/l

  • Least co

Least costly o stly option tion Least co Least costly o stly option tion

  • Requires existing tank

Requires existing tank Requires existing tank Requires existing tank modification or additional modification or additional modification or additional modification or additional tankage tankage

Anoxic Oxic Anoxic Oxic Clarifier Internal Recycle RAS

tankage tankage

WAS

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SLIDE 13

Additional tankage Additional tankage required for Bardenpho quired for Bardenpho

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SLIDE 14

Separate Separate Separate Separate-

  • Stage

Stage Stage Stage Denitrification Denitrification Denitrification Denitrification Denitrification Denitrification Denitrification Denitrification Filters Filters Filters Filters

  • Recommended when existing

Recommended when existing Recommended when existing Recommended when existing process nearly achieves process nearly achieves process nearly achieves process nearly achieves complete nitrification complete nitrification complete nitrification complete nitrification

  • No cost effective space

No cost effective space No cost effective space No cost effective space available for additional available for additional available for additional available for additional re reacto actor v r volume lume re reacto actor v r volume lume

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SLIDE 15

Denitrification Denitrification Filters ilters

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SLIDE 16

Phase I Phase I Phase I Phase I Cost Estimating Cost Estimating Cost Estimating Cost Estimating

  • Process Equipment

Process Equipment Process Equipment Process Equipment

  • Denitrification

Denitrification Denitrification Denitrification filters; Blowers filters; Blowers; Pumps Pumps; Diffusers Diffusers filters; Blowers filters; Blowers; Pumps Pumps; Diffusers Diffusers

  • Obtained m

Obtained manufacturer cost for s anufacturer cost for several plants veral plants Obtained m Obtained manufacturer cost for s anufacturer cost for several plants veral plants

  • Extrapolated equipm

Extrapolated equipment ent costs sts to other plants to other plants Extrapolated equipm Extrapolated equipment ent costs sts to other plants to other plants

  • Other Costs

Other Costs Other Costs Other Costs

  • RSMeans

RSMeans RSMeans RSMeans es estimating tools timating tools es estimating tools timating tools

  • Operation and Maintenance Costs

Operation and Maintenance Costs Operation and Maintenance Costs Operation and Maintenance Costs

  • Factors applied for disciplines

Factors applied for disciplines Factors applied for disciplines Factors applied for disciplines

  • Architectural

Architectural Architectural Architectural

  • Civil

Civil Civil Civil

  • Mechanical

Mechanical Mechanical Mechanical

  • Electrical

Electrical Electrical Electrical

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SLIDE 17

STUDY METHODOLOGY STUDY METHODOLOGY STUDY METHODOLOGY STUDY METHODOLOGY TWO PHASES TWO PHASES TWO PHASES TWO PHASES

  • Phase II (20

Phase II (2003 Phase II (20 Phase II (2003-

  • 2004)

2004) 2004) 2004)

  • Present findings from Phase I to municipalities

Present findings from Phase I to municipalities Present findings from Phase I to municipalities Present findings from Phase I to municipalities

  • Request current operational data

Request current operational data Request current operational data Request current operational data

  • Discuss planned ex

Discuss planned expansion activities pansion activities Discuss planned expansion activities Discuss planned expansion activities

  • Solicit f

Solicit feed eed back on r back on report findings port findings Solicit feed Solicit feed back on report findings back on report findings

  • Update Phase I data, costs and conclusions

Update Phase I data, costs and conclusions Update Phase I data, costs and conclusions Update Phase I data, costs and conclusions

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SLIDE 18

PHASE II FEED BACK PHASE II FEED BACK PHASE II FEED BACK PHASE II FEED BACK

  • General acceptance of study recommendations

General acceptance of study recommendations General acceptance of study recommendations General acceptance of study recommendations

  • “One process is not suitable for every plant”

“One process is not suitable for every plant” “One process is not suitable for every plant” “One process is not suitable for every plant”

  • “Detailed designs need to be

“Detailed designs need to be performed for every plant” performed for every plant” “Detailed designs need to be “Detailed designs need to be performed for every plant” performed for every plant”

  • “Costs need to be indexed to Engineering News Record

“Costs need to be indexed to Engineering News Record “Costs need to be indexed to Engineering News Record “Costs need to be indexed to Engineering News Record (ENR)” (ENR)” (ENR)” (ENR)”

  • “Costs for some facilities are too low”

“Costs for some facilities are too low” “Costs for some facilities are too low” “Costs for some facilities are too low”

  • I&C

I&C I&C I&C

  • Foundation

Foundation Foundation Foundation

  • Engineering

Engineering Engineering Engineering

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SLIDE 19

Cost Estimates Revisions Cost Estimates Revisions Cost Estimates Revisions Cost Estimates Revisions

  • Moved costs for 2002

Moved costs for 2002 Moved costs for 2002 Moved costs for 2002

  • Sept. 2004

2004

  • Sept. 2004

2004

  • Applied 1

Applied 10% to site % to site Applied 1 Applied 10% to site % to site-

  • limited pl

limited plants such as Cox Creek and Sod Run ants such as Cox Creek and Sod Run limited pl limited plants such as Cox Creek and Sod Run ants such as Cox Creek and Sod Run

  • Added $50/ft

Added $50/ft Added $50/ft Added $50/ft2

2 for geotechnical at select plants

for geotechnical at select plants for geotechnical at select plants for geotechnical at select plants

  • Added methanol systems for each plant

Added methanol systems for each plant Added methanol systems for each plant Added methanol systems for each plant

  • Added methanol control at plants with

Added methanol control at plants with Added methanol control at plants with Added methanol control at plants with denite denite denite denite filters filters filters filters

  • Nitrate analyzers and loop controllers

Nitrate analyzers and loop controllers Nitrate analyzers and loop controllers Nitrate analyzers and loop controllers

  • Added lift pumping stations at plants with

Added lift pumping stations at plants with Added lift pumping stations at plants with Added lift pumping stations at plants with denite denite denite denite filters filters filters filters

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SLIDE 20

RAW INFLUENT SCREENING GRIT REMOVAL PRIMARY CLARIFIERS ANAEROBIC ANAEROBIC ANAEROBIC ANAEROBIC OXIC ANOXIC ANOXIC ANOXIC ANOXIC OXIC OXIC OXIC SECONDARY CLARIFIER FILTRATION UV DISINFECTION OUTFALL TO MONOCACY RIVER

Existing Ballenger Wastewater Treatment Plant 6.0 mgd

MIXED LIQUOR RECYCLE RAS

  • A2O Process
  • BOD:TKN = 7:1
  • Influent Avg. TKN – 38
  • Current TN Discharge: 146,100 lbs
  • Projected TN Discharge: 54,800 lbs
  • Reduction of 91,300 lb/yr

Case Study Case Study Case Study Case Study

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SLIDE 21

RAW INFLUENT SCREENING GRIT REMOVAL PRIMARY CLARIFIERS ANOXIC ANOXIC ANOXIC ANOXIC OXIC ANOXIC ANOXIC OXIC OXIC OXIC OXIC OXIC SECONDARY CLARIFIER FILTRATION UV DISINFECTION OUTFALL TO MONOCACY RIVER

Proposed Alternate for Ballenger Wastewater Treatment Plant

ANOXIC MIXED LIQUOR RECYCLE RAS

Sufficient volume for 4-Stage Bardenpho Add partition walls Increase MLSS 2500 3500 Adequate clarifier capacity Adequate pump capacity Increase IR 200% 500% Add additional IR pumps Add chemical phosphorus removal Adequate FeCl3 System Estimated Cost for ENR: $3,800,000

Case Study Case Study Case Study Case Study

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SLIDE 22

Case Study Case Study Case Study Case Study

Cox Creek Water Reclamation Facility Anne Arundel County 15 mgd

  • Existing MLE Process
  • Insufficient Reactor Volume Available
  • No Space for Additional Tankage
  • Solution – Denitrification Filter (requires

demo of digesters)

  • Current TN Discharge: 365,300 lb/yr
  • Projected TN Discharge: 136,990 lb/yr
  • Reduction of 228,310 lb/yr
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SLIDE 23

Case Study Case Study Case Study Case Study

Cox Creek Water Reclamation Facility Anne Arundel County 15 mgd

ESTIMATED COST FOR REFINEMENT OF NITROGEN REMOVAL AT COX CREEK WATER RECLAMATION FACILITY Item Cost Process Mechanical $9,782,000 Electrical $2,935,000 Mechanical $978,000 Architectural $978,000 Site work $1,956,000 Subtotal $16,629,000 Study, Design , and Construction Phase Engineering (15%) $2,494,000 Escalation per ENR Cost Index $1,164,000 Mobilization $1,663,000 Construction Contingency (25%) $4,157,000

Total Estimated Cost $26,107,000

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SLIDE 24

Cambridge Reconfiguration to Bardenpho 123,257

$1,750,000

$0.96 $0.22 Seneca Increase in internal recycle and Reconfiguration to Bardenpho 304,410

$4,140,000

$0.92 $0.21 Piscataway Reconfiguration to Bardenpho 456,600

$8,273,000

$1.22 $0.28 Parkway Methanol Trim and Final Clarifiers 91,415

$2,800,000

$2.04 $0.37 Annapolis Additional Reactor Volume 124,828 $5,062,000 $2.73 $0.39 Ballenger Increase in internal recycle and Reconfiguration to Bardenpho 91,323

$4,831,000

$3.56 $0.81 Marley-Taylor Addition of anoxic and

  • xic volume

25,200

$11,356,000

$30.29 $1.89 Freedom Process optimization and Reconfiguration to Bardenpho 53,235

$3,472,000

$4.38 $0.99

  • L. Patuxent

Denitrification filters 194,523

$28,000,000

$9.68 $1.78 Cumberland IR, RAS Pumps, additional reactor volume, reconfiguration to Bardenpho 228,308

$16,500,000

$4.85 $1.10 Sod Run Denitrification filters 304,410

$22,568,000

$4.98 $1.13 Westminster Denitrification filters 76,114

$8,600,000

$7.64 $1.72 Hagerstown

Denitrification filters

133,940

$8,900,000

$4.46 $1.11 Conococheague None NA

NA

NA NA Frederick Denitrification filters 104,528

$9,900,000

$6.37 $1.41 Bowie Denitrification filters 50,228

$1,000,000

$0.55 $1.75 Cox Creek Denitrification filters 228,308

$26,107,000

$7.69 $1.74 Back River Denitrification filters 2,739,690

$250,850,000

$6.15 $1.39 Salisbury NA 333,800

$30,175,000

$5.30 $4.18 Hurlock Additional reactor volume 50,228

$6,200,000

$8.30 $3.76

TOTA TOTAL 5,714, 714,000 000 AVE. $5. $5.90 90 $1. $1.38 38 NOTES NOTES: MAX MAX. $30. $30.29 29 $4. $4.18 18 MIN. MIN. $0. $0.55 55 $0. $0.21 21

CO COST PER G PER GALLON TR TREATED ( (3) ES ESTI TIMATED E ENR COST ST (SEP (SEPT. 20

  • T. 2004

04 ENG

  • ENG. NEWS

WS RECO CORD RD CO COST IND INDEX) X) CO COST PER PER PO POUN UND D RE REMOVED ( (2) PO POUN UNDS DS T TN RE REMOVED WI WITH EN TH ENR MO R MODIF DIFICAT CATION ONS S (1 (1) PL PLAN ANT EX EXIS ISTING (OR NG (OR CURR CURREN ENTLY DES TLY DESIGN GNED) ED) BNR BNR PROC OCESS ESS Johannesburg EN ENR M MODI DIFI FICATIONS Modified Ludzack-Ettinger (MLE) Modified Ludzack-Ettinger Step Feed 4-Stage Bardenpho 4-Stage Bardenpho Schreiber System A2O Modified Ludzack-Ettinger Step Feed A2 O Modified MLE/A

2O

Modified Johannesburg Modified Ludzack-Ettinger A2O VT2 Oxidation Ditch Modified Ludzack-Ettinger Modified Ludzack-Ettinger

A2O Trickling Filter

4-Stage Bardenpho

Total Pounds Nitrogen Total Pounds Nitrogen Removed with ENR: 5,714,000 Removed with ENR: 5,714,000 Cost per lb. removed Cost per lb. removed Cost per gal. treated

  • st per gal. treated

Avg Avg $ 5.90 5.90 $ 1.38 $ 1.38 Max Max $30.29 $30.29 $ 4.18 $ 4.18 Min Min $ 0.55 0.55 $ 0.21 $ 0.21

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SLIDE 25

Results Results Results Results

Cost per Gallon of ENR Cost per Gallon of ENR Cost per Gallon of ENR Cost per Gallon of ENR Improvements Improvements Improvements Improvements

$0.00 $0.50 $1.00 $1.50 $2.00 $2.50 $3.00 $3.50 $4.00 A n n a p

  • l

i s H u r l

  • c

k S a l i s b u r y C u m b e r l a n d P a r k w a y S e n e c a B a l l e n g e r C a m b r i d g e P i s c a t a w a y F r e e d

  • m

M a r l e y T a y l

  • r

L . P a t u x e n t S

  • d

R u n H a g e r s t

  • w

n W e s t m i n s t e r F r e d e r i c k B

  • w

i e B a c k R i v e r C

  • x

C r e e k ADDITIONAL REACTOR VOLUME REQUIRED CONVERSION TO BARDENPHO WITHIN EXISTING REACTOR VOLUME DENITRIFICATION FILTERS

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SLIDE 26

CONCLUSIONS CONCLUSIONS CONCLUSIONS CONCLUSIONS

  • Single phase implementation of

Single phase implementation of ENR is most cost effective ENR is most cost effective Single phase implementation of Single phase implementation of ENR is most cost effective ENR is most cost effective

  • Alternative carbon sources add flexibility

Alternative carbon sources add flexibility Alternative carbon sources add flexibility Alternative carbon sources add flexibility

  • Independent study required to establish best treatment

Independent study required to establish best treatment Independent study required to establish best treatment Independent study required to establish best treatment alternative alternative alternative alternative

  • Average costs

Average costs Average costs Average costs

$5.90 per pound nitrogen removed $1.38 per gallon treated

  • Closely matches previous BNR costs

Closely matches previous BNR costs Closely matches previous BNR costs Closely matches previous BNR costs

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SLIDE 27

Prepared for

Maryland Department of the Environment

Refinement of Nitrogen Removal from Municipal Wastewater Treatment Plants QUESTIONS?