More Affordable, Reliable and Recoverable Nutrient Removal

Jim Fitzpatrick Senior Process Engineer

More Affordable, Reliable and Recoverable Nutrient Removal

James Barnard Global Practice & Technology Leader

Oct

ober

19,

201

6

2

Fitzpatrick & Barnard | More Affordable, Reliable and Recoverable Nutrient Removal |

• Drivers• Optimize conventional treatment• Avoid unintended consequences• Wet-weather strategies• Closing thoughts and open discussion

AgendaOctober 19, 2016

Drivers

• Aquatic ecology• Agricultural needs• Regulatory pressures• Economics

4


Phosphorus freshwater harmful algal blooms (HAB)Nitrogen Estuary and marine eutrophication and hypoxia

Near and far.Large and small. Point and non-point.

October 19, 2016

http://water.usgs.gov/nasqan/images/nasqan_ms_web.jpg

Lake Erie, 2011

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016)

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201

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sults

5


Case-by-case watershed studies

• Prevent internal reservoir nutrient cyclingA. Keep reservoir mixed/aerated. Prevent stratification.B. Supply nitrates, air, and/or oxygen to hypolimnion. Occoquan Reservoir etc.

Cubas et al., Water Environment Research, Feb 2014, 123-133.

Sometimes nitrates actually decrease HABOctober 19, 2016

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ce: h

ttp:

//w

etla

ndin

fo.e

hp.q

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ogy/

http://wetlandinfo.ehp.qld.gov.au/wetlands/ecology/

http://wetlandinfo.ehp.qld.gov.au/wetlands/ecology/


“The phosphorus content of our land, following generations of cultivation, has greatly diminished. It needs replenishing. I cannot over-emphasize the importance of phosphorus not only to agriculture and soil conservation, but also the physical health and economic security of the people of the nation. Many of our soil deposits are deficient in phosphorus, thus causing low yield and poor quality of crops and pastures…."

-President Franklin D. Roosevelt, 1938

Increasing population requires better phosphorus management

October 19, 2016

6

7

Return to agricultural roots

October 19, 2016Fitzpatrick & Barnard | More Affordable, Reliable and Recoverable Nutrient Removal |

From K. Ashley et al. A brief history of phosphorus: From the philosopher’s stone to nutrient recovery and reuse. Chemosphere (2011), doi:10.1016/j.chemosphere.2011.03.001

8


2012 Great Lakes Water Quality AgreementOctober 19, 2016

From https://www.epa.gov/glwqa/recommended-binational-phosphorus-targets#what-targets

Reduce spring TP and OP loads 40% to control cyanobacteria

Reduce TP loads 40% to control hypoxic “Dead Zone”

Additional research to address excess Cladophora

https://www.epa.gov/glwqa/recommended-binational-phosphorus-targets#what-targets

9

Fitzpatrick & Barnard | More Affordable, Reliable and Recoverable Nutrient Removal | October 19, 2016

10


• Increased monitoring, research, and planning• Integrated and adaptive watershed management

1. Agricultural Best management practices (BMPs)2. Urban stormwater CSO control, wet-weather flow treatment3. POTWs Tiered point source limits (BNR, ENR, LOT, etc.). TP generally higher

priority than TN for GLUMR states.4. Watershed trading

State regulatory strategiesOctober 19, 2016

11


Not a substitute for project-specific alternatives evaluations and opinions of probable costs

• Low hanging fruits:• TP removal POTW• TN removal Agriculture (sometimes POTW)

Historical costs of different practices

October 19, 2016

Source: WEF (2015) The Nutrient Roadmap, Figures 5.12 and 5.13

Optimize conventional treatment

• Phosphorus removal• Fermentation and VFA• Side-stream EBPR (S2EBPR)

• Precipitation and floc adsorption— Iron (ferrous, ferric)— Aluminum (alum, PACl, aluminate)— Calcium (lime)— Magnesium

• Clarification / filtration• Media adsorption / ion exchange• Chemicals + UF membranes• Reverse osmosis

• Air or steam stripping• Ion exchange• Break-point chlorination• Activated carbon

Many alternatives for nutrient removal

13BNR = Biological Nutrient Removal. Phosphorus and nitrogen.

PHOSPHORUS CONTROL NITROGEN CONTROL

Physical/ChemicalProcesses

BiologicalProcesses


Struvite Precipitation

• Ammonification (hydrolysis)• Nitrification• Denitrification• Deammonification (anammox)

Enhanced Biological Phosphorus Removal• “Luxury Uptake”• “Bio-P Removal”• Phoredox (AO)

Applying BNR lessons from Mother Nature

14“We’ve come a long way, baby” - Loretta Lynn, 1978


Barnard introduces PhoRedox & Bardenpho in South Africa

U.S. patents for A/O, A2O, etc.

Primary sludge fermentation in northwest U.S. and Canada

DeammonificationStruvite Recovery

1970’s 1980’s 1990’s 2000’s

S2EBPR

2010’s

15


In hindsight…side-stream RAS anaerobic zone, chemical P recovery, mainstream P uptake

• High-rate activated sludge• No nitrification• All influent to aeration basin

• RAS stripper tank• 30-40 hr SRT• P release from deep anaerobic conditions

• Supernatant treated with lime• P removed as calcium hydroxy-apatite, Ca10(PO4)6(OH)2

• Fuhs & Chen find phosphate accumulating organism (PAO) Acinetobacter

Early phosphorus removal

Aerated Settling

Effluent

Stripper

Wasted Biomass

Return Biomass

Influent Wastewater

Lime

P-enriched Lime Sludge

Phostrip Process (1962)

October 19, 2016

16


Barnard’s original pilot had side-stream anaerobic zone with mixed liquor fermentation

• Fermenter basin not deemed important at the time• Excellent phosphorus removal resulted that could not be

replicated in laboratory• Barnard suggested biomass (with PAO) should pass through

anaerobic phase with low ORP to trigger EBPR• Suggested Phoredox process by adding anaerobic zone

Mixed liquor fermentation (MLF)

Waste Activated Sludge100 m3/d Daspoort Pretoria WWTP Pilot (Barnard, 1972)

October 19, 2016

17


Researchers found Accummulibacter predominant PAO

L e g e n d

(A) (B)

(C) (D)

Anaerobic Anoxic Aerobic

Reduced Nitrates to Anaerobic zone

Phoredox process flow sheets

October 19, 2016

18


• Volatile fatty acids (VFAs) drive EBPR mechanism of phosphate accumulating organisms (PAO)

• Anaerobic zone required• Mixture of VFAs required for PAO

to thrive

Conventional EBPR thinking

Acetic47%

Propionic40%

Butyric8%Isobutyric

2%

2-Methylbutyric1% Isovaleric

1% Valeric1%

Fermentate AnalysisWakarusa WRF (Lawrence, KS 2007)

PAO Luxury Uptake Mechanism(Fuhs & Chen, 1975)

Oxic(Aerobic)

Anaerobic

VFA

First Fermenter Kelowna BC, 1979

October 19, 2016

10-mgd WWTP saving $80,000 per year with EBPR instead of chemicals

• Collection system odor control projects “robbed” VFA

• Different alternatives over 11-yr period:• Alum• Molasses (boost rbCOD)• Fermentation (boost VFA)

• Now ferment in primary clarifiers, PS fermenter and anaerobic zones

19

Case study of EBPR optimization


10-mgd Eagles Point WWTPCottage Grove, MN

20


Example of EBPR + filters:McDowell Creek WWTP

October 19, 2016

From Schauer, P. and deBarbadillo, C. (2009) Pushing the Envelope with Low Phosphorus Limits, PNCWA

21


Example of chemical P removal + filters:Northwest Cobb WRF

October 19, 2016

From Schauer, P. and deBarbadillo, C. (2009) Pushing the Envelope with Low Phosphorus Limits, PNCWA


22

Westbank with Fermenter

TN < 6 mg/L BOD < 5 mg/L TSS < 2 mg/L TP < 0.15 mg/L

Westside Regional WWTP, aka “West Bank WWTP” (West Kelowna, BC)

X

October 19, 2016

Regional District of Central Okanagan

http://www.regionaldistrict.com/


23

Westside Regional WWTP

Primary Anaerob Anoxic 1 Anoxic 2 Anoxic 3 Aerobic 1 Aerobic 2 Aerobic 35.36 20.56 2.20 1.84 1.60 0.50 0.20 0.03

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00Pr

imar

y

Anae

rob

Anox

ic 1

Anox

ic 2

Anox

ic 3

Aero

bic 1

Aero

bic 2

Aero

bic 3

Phos

phor

us m

g/L

P uptake in Anoxic and Aerobic Zones

October 19, 2016

Tetrasphaera ferment and denitrify. Non-filamentous variety also PAO.

Non-filamentousTetrasphaera

24


• Mixed Liquor Fermenters• Sacramento, CA• Olathe, KS• Pinery AWWTP, CO• Henderson, NV• Blue Lake & Seneca WWTP, MN• Joppatowne, MD• South Cary, NC• St. Cloud, MN

Other U.S. examples of side-stream EBPR (S2EBPR)

Off-line MLF Basin with 5-stage Bardenpho5.3-mgd Cedar Creek WWTP

(Olathe, Kansas)

S2EBPR Design for 181-mgd BNR EchoWater Project

(Sacramento, California)

Anaerobic Anaerobic Anoxic

OFFONInfluent

RAS MLR

In-line MLF (Pinery, Henderson, St. Cloud, etc.)

October 19, 2016


S2EBPR retrofits easier than conventional EBPR

S2EBPR in 75+ facilities in 10+ configurationsOctober 19, 2016

25

26


Dunlap et al., 2016; Stokholm-Bjerregaard et al., 2015

• Side-stream promotes PAO species Tetrasphaera, which also ferments higher carbon to VFA

• Accumulibacter PAO use VFA produced by Tetrasphaera, which also denitrify under anoxic conditions

Latest research: S2EBPR performs better than conventional EBPR

October 19, 2016

• Side-stream protected from wet weather flows• Why did we miss this until now?

• Tetrasphaera need ORP -300 mV; most anaerobic zones struggle to get -150 mV• Impossible to achieve with NO3 or DO present• Turbulence, air entrainment, or coarse bubble

air mixing prevent low ORP• Mixing energy too high (>0.08 hp/kcf)• Weak primary effluent dilutes VFA


• Static mixing chimney

• Low-speed impellers

Energy efficient mixing is one key

October 19, 2016

27

RAS

MLR

Primary Effluent

Anaerobic or Anoxic Zone

Mixing Chimney

28


IF we need even lower TP…

October 19, 2016

Exceptions to above breakpoints. Case-specific studies recommended.

WE&T, Oct 2011, pp 52-55

A - C

hem

ical

Relia

ble

Al, F

e or

Ca

B - B

ioch

emic

ally

Relia

ble

VFA

A an

d/or

B+

Filtr

ation

Terti

ary

Syst

em

0.01

0.1

1

Annu

al A

vera

ge E

fflue

nt T

P (m

g/L)

Tertiary Alternatives• Chemically enhanced settling

/ filtration / DAF• Media adsorption / IX• Algal-based activated sludge• RO membrane

Significant sustainability questions about overly stringent TN limits for POTWs.

• Post anoxic/oxic• 4 or 5-stage Bardenpho

• Denitrifying filter• Deammonification vs.

imported carbon• Point vs. non-point load

reductions. Watershed nutrient trading?

• Stratified reservoirs may benefit from nitrates in hypolimnion for HAB control (Cubas et al., 2014).

IF we need even lower TN….

29

AX OX AX OX

NH3-N: 0.1 to 2 mg/LTN: 3 to 5 mg/L

TP: 0.5 to 1.5 mg/L

AN

MeOH (usually)

AX OX

NH3-N: 0.1 to 2 mg/LTN: 3 to 5 mg/L

TP: 0.2 to 0.5 mg/L

MeOH (or equal)

AN



• Increased process stability• Biological selector helps prevent sludge bulking,

decrease sludge volume index (SVI).• Side benefits from denitrification

• Recover some alkalinity. Better nitrification and effluent buffering.

• Offset some O2 demand. Potentially lower aeration costs.

• More stable sludge blanket in secondary clarifier.• Potential nutrient recovery

Other reasons to consider BNR besides effluent quality

October 19, 2016

30

Avoid unintended consequences• Solutions to biosolids impacts

32Important for reaching energy, carbon footprint and nutrient goals…sustainably.

Causes• PAOs in WAS

anaerobically release (PO4)3-, Mg2+ and K+.

• NH4+ released later

during digestion.

Consequences• Nutrient recycle• Struvite scaling• Vivianite scaling if Fe2+

present• Decreased biosolids

dewaterability

Making BNR work with anaerobic digestion

From Shimp, G.F.; Barnard, J.L.; Bott, C.B. It’s always something. Water Environment & Technology,

June 2014, 26(6), 42-47.



Project-specific evaluation and selection

Struvite Sequestration Struvite Recovery

• Reduce nuisance scaling and deposits• Reduce P & N recycle loads• Improve biosolids dewaterability• Optional fertilizer recovery add-on

• Reduce nuisance scaling and deposits• Reduce P & N recycle loads• Decrease P in biosolids• Recovered fertilizer product

Turn struvite problem into the solutionOctober 19, 2016

33


Choices include Ostara Pearl®, MHI Multiform™, CNP AirPrex®, Schwing Bioset/NuReSys®, KEMA Phred™, and DHV Crystalactor ®

Main Goals• Minimize nuisance

scaling and deposits• Improve biosolids

dewaterability• Reduce P & N

recycle loads• Decrease P content

of biosolids• Recover fertilizer

product

Struvite recovery/sequestration gaining traction

October 19, 2016

34

35


• 1.4 BGD capacity• TP ≤ 1 mg/L (1 Feb 2018)

• Optimize EBPR• Reduce TP recycle

• Predicted struvite recovery• 5,350 lb/day PO4-P• 7,700 ton/yr fertilizer

World’s largest nutrient recovery facility

Stickney WRP

Struvite Recovery Facility

Pearl® Reactor (Upper Level)

2016 Opening

Product Silos

October 19, 2016

• Minimizes ammonia return• Digester liquors ideal for anammox• Advantages to conventional

nitrification/denitrification:• Much less energy• No carbon required• Lower alkalinity demand

Also consider side-stream deammonification for TN

36


Leading edge technology for digester return streams

Blue Plains AWTP Blue Plains AWTP

World’s Largest Facility (DEMON®, Under Construction)

Pilot■ Henrico, VA■ Brooklyn, NY■ Egan WRP, MWRDGC, IL■ Robert W. Hite WRF, Denver, CO■ Joint WPCP, Los Angeles County, CA■ Mill Creek WWTP, Cincinnati, OH■ St. Joseph, MO■ Tomahawk WWTF, Johnson County, KS

Full-Scale■ HRSD, VA■ Alexandria, VA■ Greeley, CO■ Guelph, Ontario, CAN■ Durham, NC■ Washington, DC■ Pierce County, WA■ Egan WRP, MWRDGC, IL

Since 2012

Wet-weather strategies• Don’t upset your BNR bugs• BNR can be designed to “weather the storm”

38Maximizing biological treatment of wet-weather flows

• Temporary change to contact stabilization mode for wet-weather flows

• “Biological contact” or “biocontact”

• Good fit for plug-flow basins

Deep step-feed helps “weather the storm”


MJHB with Wet-Weather Step-Feed

AX OXANAX

2Qavg < Q < 3Qavg

Blue River Main WWTP Johnson County, Kansas

3-stage Modified Johannesburg

39Another way to reduce SLR to clarifiers… temporarily.

• Transfer some RAS or MLSS to offline storage.• Return biomass after storm flows pass.• Good fit for complete-mix baxins, oxidation ditches, etc.

Biomass transfer accomplishes same thing


MLSS = 1,000 mg/L(Off-loading MLSS)

MLSS = 2,300 mg/LMLSS = 2,300 mg/L

BioWin Process Modelof RAS Transfer OperationsOffline Biomass Storage

Rogers, Arkansas5-stage Bardenpho with Oxidation Ditch


Blending or auxiliary treatment for higher peaking factors

October 19, 2016

40

Background diagram from: U.S. EPA, Sanitary Sewer Overflows and Peak Flows Listening Session, June 30, 2010

Background diagram from: U.S. EPA, Sanitary Sewer Overflows and Peak Flows Listening Session, June 30, 2010

Auxiliary

Great Lakes HRT exampleOctober 19, 2016

41


Toledo, OhioBay View Water Reclamation Plant

232-mgd DensaDeg HRC Facility

• Nitrifying activated sludge with parallel HRC train

• 45 mgd average dry weather• 70 mgd annual average• 400 mgd peak hour

Parameter Average Effluent (mg/L, 2007-2009)

TSS 21

CBOD5 22

TP 0.3


Consider dual-use for both dry and wet weather benefits

October 19, 2016

42Examples include Fox Metro, IL; Johnson County, KS; Little Rock, AR

CO

MP

RE

SS

IBLE

MED

IA F

ILT

RA

TIO

NSl

udge

/ Ba

ckw

ash

PrimaryClarifiers

Aeration

SecondaryClarifiers

HRC or HRF

DegrittingScreening

Disinfection

PrimaryClarifiers

Aeration

SecondaryClarifiers

HRC or HRF

DegrittingScreening

Disinfection

Aeration

SecondaryClarifiers

HRC or HRF

DegrittingScreening

Disinfection

Headworks Headworks Headworks

Closing thoughts and open discussion

44


BNR at lower cost, lower energy and smaller footprint

Granular activated sludge expands to U.S.

October 19, 2016

• Aqua-Aerobic Systems, Inc.• Exclusive U.S. supplier• Full-scale demonstration at Rock River WRD (Rockford, IL)

• Black & Veatch• Teaming agreement with RHDHV

GranularActivated

Sludge

ConventionalActivatedSludge

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwj5iLPq877PAhUJ3YMKHbNUCdoQjRwIBw&url=http://www.inys.org/royal-haskoningdhv-to-support-inys-launch-in-jakarta/&psig=AFQjCNHWuFk3tfS3gNhnZyC1QEon65sodQ&ust=1475593356598688

45


Stay tuned!• http://www.barleyprize.com/• #barleyprize• B&V on judging panel

Seeking radically cheaper technology for <0.01 mg-P/L

October 19, 2016

http://www.barleyprize.com/



http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjqnOOQ_OnOAhXGZCYKHWraAPEQjRwIBw&url=http://www.evergladesfoundation.org/2016/05/17/george-barley-water-prize-launching-in-summer-2016/&psig=AFQjCNFlTlcRJiK4SCwk8eKx3twCBWjnOQ&ust=1472675020470855

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjk8NT0gOrOAhUIRiYKHfzrC8sQjRwIBw&url=http://www.evergladesfoundation.org/&psig=AFQjCNHX51FC5gjh2JcxJsjomGnCXOh2Xw&ust=1472676284234732

46


Site-specific optimization. No one-size-fits-all.

Side-stream EBPR (S2EBPR)• Increase reliability of chemical-free phosphorus removal• Increase EBPR feasibility and performance for more process flow sheets• Lower cost than conventional EBPR• If anaerobic digestion evaluate struvite recovery and deammonification

Wet-Weather Flows• Optimize existing facilities with step-feed or biomass transfer• Consider auxiliary treatment for peaking factors 3

Regulatory Strategy• Sustainable goals must recognize site-specific water body response, influent

carbon limitations, energy/carbon footprint and nonpoint sources.• Annual average limits. Daily, weekly, or monthly not practical for

eutrophication concern.• TP=0 not feasible due to soluble non-reactive phosphorus (sNRP).• TN=0 not feasible due to recalcitrant dissolved organic nitrogen (rDON).

Total inorganic nitrogen (TIN) limits vs TN. Colorado & Ohio precedence.

SummaryOctober 19, 2016

www.bv.com

© Black & Veatch Holding Company 2012. All Rights Reserved. The Black & Veatch name and logo are registered trademarks of Black & Veatch Holding Company.

• Jim Fitzpatrick | Senior Process Engineer• 913.458.3695 | [email protected]

• Dave Koch | Client Services Director• 312.683.7829 | [email protected]

• James Barnard | Global Practice & Technology Leader• 913.458.3387 | [email protected]•

• Diane Sumego | Client Services Director• 913.458.4799 | [email protected]

http://www.bv.com/

mailto:[email protected]





Bullpen

49

How will we meet growing phosphorus demand?


From S. Van Kauwenbergh. (2010), World Phosphate Rock Reserves and Resources. Presented at Center for Strategic and International Studies

Recovery is part of long-term solution


…different fates and ecosystem responses

Different nutrients … different forms …

October 19, 2016

50

Total KjeldahlNitrogen (TKN)

NH3-N

ORG-N

rDON

NO2-N

NO3-N

Total Nitrogen

(TN)

Total Inorganic Nitrogen (TIN)

OP or PO4-P

ORG-P

Total Phosphorus

(TP)

Reactive Phosphorus

sNRP

51


Potentially lower life-cycle costs

Why consider enhanced biological phosphorus removal (EBPR)?

2.0 1.5 1.0 0.5

Rel

ativ

e Li

fe C

ycle

Cos

t

Effluent TP in mg/L

Chemical Addition

Conversion to EBPR

October 19, 2016

Each POTW is different.

• Not just BOD, TSS, NH3-N and TP

• Influent fractions of C, N and P species• VFAs for EBPR• Readily biodegradable

COD (rbCOD) for denitrification

• Daily and seasonal variations

• Bad odors usually good sign for BNR

Special sampling study for BNR planning and optimized design

52

0

5

10

15

20

25

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

VFA/rbCOD ratio

rbCO

D/O

P ra

tio

Reedy Creek (South Carolina)

McDowell Creek (North Carolina)Reliable EBPR above the curve

EBPR model curveNo

Fermentation

HRSD VIP (Virginia)

Eagles Point WWTP (Minnesota)

With Fermentation


53


• Measure influent TKN and Ammonia

• RDON can only be measured from full-scale or pilot activated sludge BNR plant to remove all forms of biodegradable nitrogen.

• TIN better indicator of activated sludge performance than TN.

Nitrogen fractions

Total Kjeldahl Nitrogen (TKN)

NH3-N

ORG-N

rDON

NO2-N

NO3-N

Total Nitrogen

(TN)

Total Inorganic Nitrogen (TIN)

October 19, 2016

54


• Measure influent OP after acid digestion to determine total reactive phosphorus

• sNRP can only be measured from full-scale or pilot activated sludge plant.

Phosphorus fractions

OP or PO4-P

ORG-P

sNRP

Total Phosphorus

(TP)

Reactive Phosphorus

October 19, 2016


Example of conventional EBPR

October 19, 2016

55However…EBPR observed in full-scale facilities without mainstream anaerobic zone.

Oxic Cell 1

Anaerobic Cell 3 effluent

Mixers24-mgd Clean Water Plant

Wyoming, Michigan

56


Adsorption without metal salt dosing• Polymeric metal oxide media

developed by Asahi• In-situ regeneration with NaOH• Long-term pilots in U.S. and

Japan

October 19, 2016

Cross sectionExterior Surface Internal Structure

Fibril

Cavities


Fibril

Cavities

Exterior Surface Cross Section Internal Structure

• 0.13-mgd demonstration at Kasumigaura Lake WWTP (near Tokyo) averaged TP < 0.03 mg/L during first year

• 10-mgd facility on hold, pending ultralow permit limits

57


Another S2EBPR example

October 19, 2016

MLE process exhibited EBPR performance

Iowa Hill WWTF (Breckenridge, CO)

Sec ClrBAF

Flash Mix

Rxn Chamber

Densadeg

Filtered

0

0.05

0.1

0.15

0.2

0.25

0.3

9/8/2011 9/9/2011 9/10/2011

Effl

uent

Ort

ho P

mg/

L

Courtesy: Chris Maher, Upper Blue Sanitation District

58


• Step-Feed Denitrification – No ML recycle pumping, but limits denite capacity.

• Oxidation Ditch – Bio-denitro™, Oxystream™, Carousel®, and others. Can use ditch velocity instead of separate pumps to recycle mixed liquor in some cases.

• Cycled Aeration – alternate anoxic/oxic• Small Footprint Options

Lots of variations on MLE and BNR themes

October 19, 2016

Suspended Growth Fixed-Film HybridSequencing Batch Reactor (SBR)

Biologically Active Filter (BAF)

Integrated Fixed-Film Activated Sludge (IFAS)

• Static media• Moving mediaMembrane Bioreactor

(MBR)Moving Bed Biofilm Reactor (MBBR)

Magnetite Ballasted Biomass (BioMag™)Granular Activated Sludge

3-stage usually offers most bang for buck.Many different configurations and variations.

Anaerobic Zone• No DO and no NOX

• Fermentation• P release• Biomass selector

MLE process can be added for TN control

59

Anoxic Zone• DO < 0.5 mg/L• NOX from ML recycle• Heterotrophic

denitrification

Oxic Zone• DO: 2-3 mg/L• P uptake and removal with WAS• Autotrophic nitrification• Heterotrophic BOD removal

OXAn

oxic

Typical Range (not TBEL)TP: 0.5 to 1.5 mg/LNH3-N: 0.1 to 2 mg/LTN: 6 to 10 mg/L

AN AX

Mixed Liquor Recycle

Modified Ludzack-Ettinger (MLE)



Site-specific process modeling and cost evaluations

Step-Feed Alternative• No mixed liquor recycle

pumping lower energy• Modest denitrification

• O2 & ALK benefits• Process stability

• Evaluate ammonia bleed-through

Consider step-feed anoxic zones vs. MLEOctober 19, 2016

60

AnoxicAnoxic/OxicSwing Zone

Mixers

ML Recycle Pump

RAS

PE

Pri mary Effl

u ent130-mgd Mill Creek WWTP, Cincinnati, OHBNR Alternatives Study

0

2

4

6

8

10

12

14

1Q 2Q 3Q 4Q 5Q 6Q 7Q 8Q

Efflu

ent N

O3,

mg/

L

Mixed Liquor Recycle Ratio

Inf TKN = 30 mg/L

61


Tertiary P removal strategies

October 19, 2016

Also dissolved air flotation (DAF), algal-based systems, low-pressure membrane filters (MBR or tertiary) and reverse osmosis alternatives

AChemically Enhanced

Clarification and Polishing

Filters

BChemically Enhanced Two-Stage

Filters

CFiltration and Adsorption

Media with P Recovery


Clarification (CEC) and Polishing

Filters

62

CEC generally involves 4 steps

1. Coagulant Addition. Rapid mix. Add metal salt and/or cationic polymer to “break” colloids (de-emulsify)

3. Flocculation. Medium to low turbulence. Build floc and “sweep” small particles into floc. Enhance floc settling.

4. Clarification. Non-turbulent. Separate solids from liquids.

2. Flocculant Addition. Rapid mix. Add anionic or nonionic polymer. Optional if steps 1 and 3 are ideal.

Turbulence


Jar tests to evaluate and guide full-scale optimization

• Coagulation• Al3+/Fe3+/Ca2+ dose• Alkalinity/pH• Rapid mixing criteria

• Flocculation• Polymer type and dose• Rapid mixing criteria• Slow mixing criteria• Sludge recirculation

Steps 1-3 determine success

63


• Coagulant dose higher than PO4 precipitation alone• Metal hydroxyl floc formation

• pH/alkalinity• Deflocculation from monovalent cations

64

Clarification mechanisms

Gravimetric

Filtration*

* Generally requires particle conditioning, depends upon waste and filter type.

Flotation

SettlingSurface ChargeNeutralization

CoagulationCo-precipitation

FlocculationAdsorption

Particle Conditioning

Sieving (Surface) Adsorption (Depth)


CEC example - Durham AWTF (Tigard, OR)

October 19, 2016

65


Conventional drinking water technologies

Tertiary clarifier with paddle flocculator Dual media granular filters

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwi-1b_K7unOAhUD0iYKHevDAIIQjRwIBw&url=http://www.cleanwaterservices.org/about-us/our-history/&psig=AFQjCNEK0p3ssJCW4mZvD0Rab_AdwOauEg&ust=1472671354220877

Other full-scale examplesOctober 19, 2016

66


Facility Capacity(mgd) Technology

Average Effluent TP

(mg/L)Farmers Korner WWTF

(Breckenridge, CO) 3 EBPR, alum, tube settlers, mixed media filters 0.002 - 0.04

Snake River WWTP (Summit County, CO) 2.6 Alum, plate settlers, mixed

media filters <0.01 – 0.04

Rock Creek AWTF (Hillsboro, OR) 39 EBPR, alum, tertiary clarifiers,

granular media filters 0.04 – 0.09

Durham AWTF (Tigard, OR) 24 EBPR, alum, tertiary clarifiers, granular media filters 0.05 – 0.1

F. Wayne Hill WRC (Gwinnett County, GA) 60 EBPR, lime, tertiary clarifiers,

filters, membranes <0.08

Alexandria AWWTP (Alexandria, VA) 54 EBPR, ferric, alum, plate

settlers, dual media filters 0.04 – 0.1

Upper Occoquan WRP (Centreville, VA) 42 High lime clarification,

multimedia granular filters 0.02 – 0.1

Noman Cole WPCP (Fairfax County, VA) 67 EBPR, ferric, tertiary clarifiers,

dual/mono media filters 0.02 – 0.13

From USEPA (2007) Advanced Wastewater Treatment to Achieve Low Concentration of Phosphorus, EPA 910-R-07-002 and Schauer, P. and deBarbadillo, C. (2009) Pushing the Envelope with Low Phosphorus Limits, PNCWA

67

ACTIFLO® Turbo

1 3 42

High-rate CEC = smaller footprintDensaDeg®

Clarifier / ThickenerReactor

Turbine DriveTurbine Draft Tube

FlowSplitter

Polymer

Sludge Recirculation Sludge

Blowdown

Settling Tube

Assembly

LaunderAssembly

Recirculation ConeLifting Assembly

Settling Tube Support

Sludge Recycle Pump

Coagulant

Rapid Mix

Reactor

Clarifier / ThickenerReactor

Turbine DriveTurbine Draft Tube

FlowSplitter

Polymer

Sludge Recirculation Sludge

Blowdown

Settling Tube

Assembly

LaunderAssembly

Recirculation ConeLifting Assembly

Settling Tube Support

Sludge Recycle Pump

Coagulant

Rapid Mix

Reactor

1 3 42

RAPISAND™

1 3 42

CoMagTM

CoMagTM

Magnetic Filter

(Optional)

1 3 42


Full-scale examples with high-rate CEC

About another 27 DensaDegs, 171 ACTIFLOs, 12 BioMags and 8 CoMags treating wastewater since 1989


Average Effluent TP

(mg/L)Iowa Hill WWTF

(Breckenridge, CO) 1.5 Alum, DensaDeg, DynaSand filter 0.017 - 0.13

Flat Creek WRF (Gainesville, GA) 20 EBPR, alum, DensaDeg <0.13

South Lyon CWP (South Lyon, MI) 4 Alum, Actiflo <0.07

Metro Syracuse WWTP (Onandaga County, NY) 126 PACl / ferric, Actiflo 0.05 – 0.09

Sturbridge WPCF (Sturbridge, MA) 1.6 BioMag BNR, alum,

CoMag 0.039

Billerica WWTP (Billerica, MA) 5.5 Alum, CoMag 0.036

68


From USEPA (2007) Advanced Wastewater Treatment to Achieve Low Concentration of Phosphorus, EPA 910-R-07-002 and case study material from Degremont (2008), Kruger (2012), and Evoqua (2015).

69



October 19, 2016




Filters


Filters




Filters

70

Blue PRO®: ferric oxide coated sand filter

Potential PROS• Continuous backwash and sand

regeneration• 30% less chemical than other

technologies• Hydrous ferric oxide return• Small footprint

Potential CONS• Higher headloss than

settling alternatives

Fe3+

final effluent

secondary effluent

mixer Continuous backwash sand filter

reject

Fe3+

mixer

reject

Continuous backwash sand filter


adapted from Benish et al. (2007)

https://www.bluewater-technologies.com/index.html



71


DynaSand® D2: co-precipitation + sand filter

October 19, 2016

Similar pros and cons as Blue PRO®

Al3+

final effluentsecondary

effluent

mixer DynaSand Deep Bed

DynaSand Standard

Bed

reject

Lamella

Thickener

AL3+

mixer

adapted from Benish et al. (2007)

Full-scale examples with chemically enhanced two-stage filters



Average Effluent TP

(mg/L)Hayden Regional WWTP

(Hayden, ID) 0.25 Ferric, Blue PRO 0.009 – 0.036

Stamford WWTP (Stamford, NY) 0.5 Poly-aluminum-silicate-

sulfate (PASS), DynaSand D2 0.005 – 0.06

Walton WWTP (Walton, NY) 1.55 PACl, DynaSand D2 0.005 – 0.06

Manotick WWTP(Ontario, Canada) 0.04 DynaSand D2 <0.03

October 19, 2016

72

From USEPA (2007) Advanced Wastewater Treatment to Achieve Low Concentration of Phosphorus, EPA 910-R-07-002 and Schauer, P. and deBarbadillo, C. (2009) Pushing the Envelope with Low Phosphorus Limits, PNCWA

DynaSand® D2 dual sand filtrationActiflo® + sand filters

ZeeweedTM tertiary ultrafiltration membranes

Side-by-side piloting at Lakeshore WPCP (Innisfil, Ontario)


Blue PRO® dual reactive sand filtration

October 19, 2016

73


74


Ultra low P effluent from all technologies during steady-state and diurnal phases

October 19, 2016

Similar results from comparative piloting including Westborough, MA (Hart et al., 2009); Coeur d’Alene, ID (Benisch et al. ,2007); Spokane, WA (Esvelt et al., 2010)

From deBarbadillo et al. (2009) Lakeshore Water Pollution Control Plant Phosphorus Removal Pilot Testing

75



October 19, 2016




Filters


Filters





• Granulated ferric oxides• Activated aluminum oxides• New polymeric metal oxide

• High selectivity for phosphate over competing anionsPO4

3- >> F- > SO42- > Br- , Cl-, NO2

- , NO3-

• High breakthrough capacity even at high flow rate• Repeatable adsorption/desorption cycle

Adsorption media alternatives

October 19, 2016

76


Average diameter 0.55 mm

True density of raw material 28 lbs/gal

Bulk density of beads 2.9 lbs/gal

Porosity 85%

Adsorption capacity 15 g-P/L-R

Resistance to acid & alkali pH 2 to 14

77


Removal and recovery process

In situ media regeneration. Phosphorus recovery.

October 19, 2016

SecondaryEffluent Filter Treated

Water

Solid/liquid separation

pHControl

Tank

ＡＣ

PrecipitationReactor

DesorptionTank

LimeTank

Ｂ AcidTank

CausticTank

AdsorptionTowers

Adsorption

Desorption

Recovery

Neutralization

Carrousel Operation Two columns in series Third column stand-by

Waste

Phosphorus-LadenSolids

U.S. pilot confirmed long-term piloting in Japan

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%Percentage of measurements at or below value

(Phase 1A, 1B, 2, & 3)

Fina

l Effl

uent

P S

peci

es (m

g/L)

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

Fina

l Effl

uent

TSS

(mg/

L) a

nd

Turb

idity

(NTU

)

OP (Hourly Online Data)OP (Daily Composite Lab Data)TP (Daily Composite Lab Data)Dissolved TP (Grab)Soluble Non-reactive P (Grab)Turbidity (Daily Composite)TSS (Daily Composite)

78


From Fitzpatrick et al. (2010) First U.S. Pilot of a New Media for Phosphorus Removal and Recovery, WEFTEC

79


Status of adsorption technology• Polymeric metal oxide media

developed by Asahi• In-situ regeneration with NaOH• Long-term pilots successful in

U.S. and Japan

October 19, 2016


Fibril

Cavities


Fibril

Cavities

Exterior Surface Cross Section Internal Structure

• 0.13-mgd demonstration at Kasumigaura Lake WWTP (near Tokyo) averaged TP < 0.03 mg/L during first year

• 10-mgd facility designed, pending ultralow permit limits

80

Concept for ultra-low P and recovery without Fe, Al or Ca salts


Sludge

Anaerobic Digestion

Dewatering Centrifuge

Biosolids

Primary Clarifiers Activated Sludge EBPR

ThickeningCentrifuge

Fermenter & Thickener

Struvite Fertilizer

VFA Effluent Filter

Anaerobic Release Tank

StruviteReactor

Mg2+

(PO4)3-

Mg2+

K+

NH4+

Phosphorus Adsorption

Media

DesorptionFluid

(PO4)3-, OH-

OH-

WASSTRIP® and Struvite Recovery

ASAHI

H+

MgNH4(PO4)·6H2O

K+

10% (PO4)3-

80% (NH4)+


BNR design must account for nutrients from biosolids dewatering

October 19, 2016

81

Anaerobic Digestion

DewateringBiosolids

Primary Clarifiers Anaerobic | Oxic

Thickening

Particulate PChemical Precipitation

WASwithPAOs

(PO4)3-, Mg2+, K+, NH4+

Particulate N & PN & P in cells

NH4+

(PO4)3-, Mg2+, K+

Secondary Clarifiers

Typical Range (not TBEL)NH3-N = 0.1 to 2 mg/LTP = 0.5 to 1.5 mg/L

82Wet-weather flows = entirely different environmental conditions

Opposite ends of the permitting spectrumOctober 19, 2016Fitzpatrick & Barnard | More Affordable, Reliable and Recoverable Nutrient Removal |

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

22,000

20 30 40 50 60 70 80 90 100

Mau

mee

Riv

er Fl

ow R

ate

(cfs

)

WPCP Daily Average Flow Rate (mgd)

8/2/2007 - 7/31/2013 Flow Data

Maumee @ Coliseum Blvd Maumee @ Anthony Blvd 36 cfs

Existing permit used 36 cfs as Q7,10 for low-flow WQBELs

Existi

ng p

erm

it av

erag

e de

sign

= 60

mgd

Existi

ng p

erm

it pe

ak

desig

n =

70 m

gd

Future Permit ConditionsDesign Average = 74 mgdDesign Peak = 85 to 100 mgd

Fort Wayne, Indiana (8/2/2007 - 7/31/2013)

Clarification alternativesOctober 19, 2016

83


Settling-Based Filtration-Based Flotation-Based1. Conventional Settling -Rectangular, Circular, Square, RTB, Shaft 1. Shallow Granular Media 1. Conventional

Floatables Removal -Skimmers, Scum baffles2. Vortex (Swirl Concentrator) 2. Deep Granular Media

3. Lamella Settler 3. Microscreens, Woven Media -Salsnes Filter, Eco MAT™ Filter

2. Dissolved Air Flotation (DAF)

4. Chemically Enhanced Settling4. Floating Media -MetaWater HRFS, BKT BBF-F

a. Conventional Basinb. Sequencing Batch- e.g. ClearCove Harvester™

c. Lamella Settler 5. Pile Cloth Media-Aqua-Aerobic Systems 3. Polymer-aided DAF

-Various suppliersd. Solids Contact / Recirculation- e.g. DensaDeg®, CONTRAFAST®

6. Compressible Media-Fuzzy Filter™, WWETCO FlexFilter™

e. Ballasted Flocculation- Microsand (e.g. ACTIFLO®, RapiSand™)- Magnetite (e.g CoMag™) 7. Fixed-Film Contact

-Biological Aerated Filter (BAF), BioFlexFilter™

4. Biocontact + DAF -Captivator®5. Suspended Growth Contact

-BIOACTIFLO™, BioMag™, Bio-CES

Enhanced RemovalSmall Footprint (High-Rate Treatment)Primary Removal Equivalent *

* If coagulation/flocculation provided, HRT EHRT (in some cases)


• Generally not. Stick closely to 40 CFR 133 definition:• Monthly average. Across entire POTW.• 001, A01, B01 approach is reasonable for blending or auxiliary treatment.• 85% metric not appropriate for separate peak flow discharge.

Is 85% removal reasonable during peak flows?

October 19, 2016

84

0%10%20%30%40%50%60%70%80%90%

100%

Event 1 Event 2 Event 3

Rem

oval

thro

ugh

Activ

ated

Sl

udge

Pro

cess

Bay View WRP - Toledo, OhioPeak Flow Pathogen Removal Study (2011-Present)

Total Suspended Solids (TSS) Bichemical Oxygen Demand, 5-day (BOD5)

Nelson WWTP - Johnson County, Kansas Wet Weather Flow Study (2003-2008)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 20 40 60 80 100 120 140

Nel

son

WW

TP B

OD

Rem

oval

, %

Nelson WWTP Collection System Flow Rate, mgd

Normal ConditionsPeak Wet Weather Flows

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0100200300400500600700800900

Nel

son

WW

TP B

OD

Rem

oval

, %

Nelson WWTP Influent BOD, mg/L

Normal ConditionsPeak Wet Weather Flows


Are we focused on the right problem?

CDC 2009-2010 report ~50% of outbreaks in U.S. surface waters were associated with cyanobacteria toxins…not pathogens

October 19, 2016

85http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6301a2.htm#fig1

Only 22% (296 of 1326 cases) were untreated venues

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6301a2.htm

86Longer term average limits and flow-tiered WQBEL offer compliance remedies.

Expect short-term higher effluent levels during peak wet-weather flows


GPS-X Model Predictions for Wet-Weather EvaluationP.L. Brunner WPCP (Fort Wayne, Indiana)

Monthly NH3–N Limit1.8 mg/l

Daily NH3–N Limit4.2 mg/l

Overly Stringent?


• Flow-tiered WLA and WQBEL.• Determine receiving stream flow rate and mixing zone

above which there is no reasonable potential to exceed facility’s wasteload allocation (WLA).

• Average weekly limits. Different statistics than MDL. Ohio, Missouri and others.

• WLA based on dynamic water quality model instead of steady-state.• More accurately reflects actual environmental fate and

transport.• More widely available and accepted now than when

recommended by USEPA guidance (1991).

Potentially better alternatives to overly stringent maximum daily limits

October 19, 2016

87


Standard approach may lead to overly stringent MDL based on chronic instead of acute

Scrutinize WQBEL derivation procedures

October 19, 2016

88

Source: Technical Support Document for Water Quality-based Toxics Control, EPA/505/2-90-001, March 1991

89


State-of-the-art guidance includes:

October 19, 2016

Sustainable solutions require site-specific plans, design and management

http://news.wef.org/wp-content/uploads/2014/10/WEF-Publication-Resource-Recovery-Cover.jpg

Engineering

More Affordable, Reliable and Recoverable Nutrient Removal