deammonification for cost-effective sidestream …€¦ · deammonification for cost-effective...

Deammonification for Cost-Effective

Sidestream Treatment

MWEA Process Seminar

November 8, 2017

Lucy Pugh, P.E., BCEE

Vice President

Wastewater Technical Practice Leader

Overview

1. What is deammonification? - the fundamentals

2. Why deammonification?

3. Sidestream deammonification

– DEMON suspended growth

– AnitaMox attached growth

– ANAMMOX granular sludge

4. Mainstream deammonification

Fundamentals of Deammonification

Fundamentals of Nitrification - Denitrification

Oxygen demand 4.57 g / g NH+4-N oxidized

Carbon demand 4.77 g COD / g NO-3-N reduced

1 mol Ammonia

(NH3/ NH4 +)

1 mol Nitrite(NO2

- )

1 mol Nitrate(NO3

- )

75% O2

100% Alkalinity

Autotrophic Nitrification

Aerobic Environment

1 mol Nitrite(NO2

- )

½ mol Nitrogen Gas

(N2 )

25% O2

40% Carbon

60% Carbon

Heterotrophic Denitrification

Anoxic Environment

Fundamentals of Nitritation - Denitritation

1 mol Ammonia

(NH3/ NH4 +)

1 mol Nitrate(NO3

- )

½ mol Nitrogen Gas

(N2 )

25% O2

40% Carbon

60% Carbon

1 mol Nitrite(NO2

- )

1 mol Nitrite(NO2

- )

• 25% reduction in oxygen

• 40 % reduction in carbon demand

• 40% reduction in biomass production


Carbon demand 2.86 g COD / g NO-3-N reduced

Autotrophic Nitritation

Aerobic Environment

75% O2

100% Alkalinity

Heterotrophic Denitrification

Anoxic Environment

Fundamentals of Deammonification


1 mol Ammonia

(NH3/ NH4 +)

1 mol Nitrate(NO3

- )

25% O2

40% Carbon

NH4+ + 1.32 NO2

- + 0.066 HCO3- + 0.13 H+

0.26 NO3- + 1.02N2 + 0.066 CH2O0.5N0.15 + 2.03 H2O

0.44 mol N2+ 0.11 NO3-

0.57 mol NO2-

Partial Nitritation

Aerobic Environment

ANAMMOX Deammonification

Anaerobic Ammonium Oxidation Autotrophic

Nitrite Reduction

(New Planctomycete, Strous et. al. 1999)

• > 60% reduction in oxygen

• Eliminate demand for supplemental carbon

• 50% of the alkalinity demand

Partial Nitritation 40% O2

50% Alkalinity

Why Deammonification?

- A Strategy for Energy Neutrality

Overall Benefit of Deammonification Processes

– Eliminates need for carbon - available for energy recovery

– Significant reduction in energy demand possible

– Reduction in alkalinity demand

0

1

2

3

4

5

6

7

Nitrification /

Denitrification

Nitritation /

Denitritation

Deammonification

(a.k.a. ANAMMOX)

kW

-hr /

kg

N r

em

ove

d

Typical Energy Demand Ranges

Activated-sludge

Aeration 55.6%

Pumping & Screening 7%

Aerated Grit Removal 1%

Primary Clarifiers 1%

Aeration48%

RAS Pumping 2%

Secondary Clarifiers 1%

Chemical Addition 2%

Filter Feed Pumping 4%

Filtration 2%

Gravity Thickening

0%

Dissolved

Air Flotation 7%

Gravity Belt

Thickener 1%

Anaerobic Digestion

9%

Belt Filter Press 1%

Centrifuge 8%

Chlorination 0%

UV Disinfection 4%

Lighting & Misc. 2%

400 MLD (105 mgd) Nitrifying Activated Sludge Facility

Distribution of Energy Usage for a

Typical BNR WWTP

The Road to Sustainable and Efficient

Nitrogen Management

1. A-Stage – maximize carbon capture

2. Biosolids – maximize energy recovery

3. B-Stage – minimize carbon and energy demand for nutrient management

1 3

3

2

Sidestream Deammonification Technologies

Centrate / Filtrate Characteristics

13

Screening Primary clarifier Biological treatmentSecondary

clarifier

River

Refuse

Sand,

grease

ThickenerDigester

Gas holder CHP

Dewatering

Sludge disposal /

beneficial reuse

SidestreamTreatment

• 1% plant influent flow

• Rich in nitrogen and phosphorus

• 15 to 25% plant influent TN load

• Ammonia: 500 to 3,000 mg-N/L

• Phosphorus: 200 to 800 mg-P/L

• Temperature: 30 to 38C

• Insufficient alkalinity for complete nitrification

• Insufficient carbon for denitrification

Reduce

Effluent TN by

≈ 20%

Challenges of Sidestream Deammonification

– Low growth rate • approximate 10 day doubling time at 30C

• <10 day has been reported (Park et. al - 5.3 - 8.9 days)

• SRT (>30 days)

– Sensitive to:• Nitrite

− Toxic- irreversible loss of activity based on concentration and exposure time

− NH4+ : NO2

- ratio 1 : 1.32

• DO - reversible inhibition

• Free ammonia (<10 -15 mg/l)

• Temperature >30C preferred

• pH (neutral range)

Sidestream Nitritation – NOB Repression

– Control

• Elevated NH3-N concentrations

• Elevated temperature (30-35 deg C)

• Low SRT (1-2 days)

• Low DO (~0.5 mg/L)

– NOB Repression Mechanisms

• Free NH3 –N inhibition of NOB > AOB

• Nitrous acid inhibition of NOB > AOB

• AOB max growth rate > NOB max growth rate at high temperatures

• AOB DO affinity > NOB DO affinity (perhaps only at high temperatures)

Deammonification Technologies

– DEMON® Suspended Growth SBR

• World Water Works

• 54 facilities in operation

• York River, VA; Alexandria, VA; Blue Plains, DC

– Cleargreen® Suspended Growth SBR

• Infilco Degremont

• 3 pilots / 3 plants in design

– TerraMox® Hybrid Suspended and Attached

• Clariant/SÜD Chemie - seepex

• 4 operational facilities (Germany)

– ANITA™Mox Attached Growth MBBR

• Veolia Water / Krüger


• James River, VA; South Durham, NC

– ANAMMOX® Granular Sludge

• Paques (Ovivo markets technology in NA)

• 26 facilities in operation; many in design/construction

ANAMMOX® Granular Process

DEMON®, Cleargreen, Terra-N

ANITATM MOx MBBR

Each DEMON cycle involves 3 time-controlled phases:

1. Fill / React – cyclical aeration and mixing

2. Settling phase

3. Decant / Discharge phase

Demon® Operational Philosophy

Reaction Settling Decant

Each DEMON process cycle involves

3 time-controlled phases:

1. Reaction – cyclical aeration

and mixing

2. Settling

3. Decant / Discharge

Demon® Operational Philosophy

Overview of Several DEMON® Plants

Facility Load

(kg N / d)

Tank Vol. (m3) Design Loading Rate

(kg N / m3 / d)

Apeldoorn 1,900 2,900 0.66

Thun 400 600 0.67

Glarnerland 250 360 0.69

Strass 600 500 1.20

• Typical volumetric design criterion = 0.7 kg N / m3 / day

• Typical removal ~90% NH3-N and ~85% TN

• Effluent NO3-N ~10% of NH3-N removed; less if bCOD available

SRT Control – cyclone retains DEMON® granules and wastes NOBs

MLSS Overflow Underflow

Greatest Anammox activity

in the cyclone underflow

• Initially the startup period for DEMON was slow

• Strass started up over a 2 year period

• Startup of Glarnerland, Switzerland occurred within 50 days using

Strass seed and a cyclone

Robust System – reliable operations and faster startup

Strass Full Scale DEMON® – Energy Savings

– 84% TN Removal at design loading rate of 0.7 kg N / m3 / day

– 1.0 - 1.3 kW-hr / kg N removed

DeammonificationNitritation /

Denitritation

Co-D

igestion

2002

81%

2003

84%

2004

95%

2005

108%

2006

105%

2007

109%

2008

124%

%

Ne

t E

ne

rgy

Pro

ducer

DEMON® Sequencing Batch Reactor – Energy Demand

– Strass undertook many energy efficiency activities

– With the introduction of DEMON® it became a net energy producer

Ma

instr

eam

De

am

monific

atio

n

Future

175%?

Sidestream

Treatment

20,200

lbs /day

NH3-N

Mainstream

Treatment

105,000

lbs/day

TKN

Operational Cost Savings

• $8.5M / year (methanol, alkalinity,

sludge processing)

• 9 year payback

• Risk mitigation for effluent TN





















ANITATM MOx MBBR

ANITA™Mox – MBBR process

• Simultaneous aerobic and anaerobic conditions in

biofilm layers

− NH3-N, alkalinity and DO in the bulk liquid

− AOBs in the outer aerobic layer

− ANAMMOX in the inner anaerobic layer

MBBR

BiofilmMedia

Liquid

Nitritation

NH4+

NO2-AOB

Anammox

N2 O2

Aerobic

AnoxicSimultanous aerobic and anoxic layers in biofilm

ANITA™Mox – MBBR process

BiofilmMedia

Liquid

Nitritation

NH4+

NO2-AOB

Anammox

N2 O2

Aerobic

AnoxicSimultanous aerobic and anoxic layers in biofilm

• ANAMMOX organisms in biofilm are protected from high

concentrations in the bulk liquid

• Less vulnerable to inhibitory compounds

− DO: 2 mg/L vs. 0.2 mg/L suspended

− NO2-N: 50 mg/L vs. 5 mg/L suspended

K5800 m2/m3

BiofilmChip M1200 m2/m3

ANITA™Mox – Different Media

MBBR = Media + Screen +Aeration

Mitigate risk of losing Anammox biomass

ANITATM Mox MBBR Deammonification

• Soljunda WWTP, Malmo, Sweden

− Pilot “BioFarm”

− Tested carrier media, mixing, aeration

• Patented aeration control to prevent NO3-

N production <10% without supplemental

mixing

• Continuous aeration 0.6 – 1.6 mg/L DO

• Demonstrated energy demand of

1.45 – 1.75 kWh / kg

NH3-N removed (Christesson et al., 2011)

ANITATM Mox Performance – Soljunda BioFarm

– ~90% NH3-N removal; ~85% TN removal

– Patented DO control strategy reduces NO3 production

<11%

– 1.4 – 1.7 kWh/kgN-NH4 removed

– Removal rates of up to 1.2 kg TN / m3 / day

– Loading rates up to 1.4 kg N / m3 / day

(Christesson et al., 2011)

BiofilmChip™

Best Performer

James River TP – Newport News, VA

– Centrate characteristics

• Flow = 0.075 MGD

• NH3-N = 890 mg/L

• Temperature = 30 °C

– Retrofit of existing tank

– Seeded from Malmö BioFarm

– James River also has 16 MGD Hybas™

(IFAS) treatment

– Serves as BioFarm


33


Process startup period – 4 months to reach full NH4-N load

4 Month Start-up Phase


30-day performance test – 90% NH3-N and 83% TN removal

83%

90%

ANITA™ Mox – Ease of Operation

– Simple, robust, reliable

– Preferred for conditions with high inert TSS

Process Attribute Promotes Ease of

Operation

Continuous flow √

304 SS air grids (reduced maintenance) √

No decanting √

No sludge wasting (MBBR) √

No SRT control √

No pre-settling √

No equipment to recycle Anammox (MBBR) √

Resistant to nitrite in influent √

U.S.-based process support and MBBR expertise √

LA County Sanitation District, CA – Pilot Stress Testing

Summary of robustness and perturbation testing

Test

No.Scenario

Perturbation

Period

Recovery

Time

1 Process power outage 24 hr < 8 hr

2 System underfeed 24 hr < 8 hr

3 System overfeed (2X) 24 hr 16 hr

4 Under aeration (No Air) 24 hr 32 hr

5 Over aeration (+23%) 24 hr < 8 hr

BiofilmMedia

Liquid

Nitritation

NH4+

NO2-AOB

Anammox

N2O2

Aerobic

AnoxicBiofilm

Media

Liquid

Nitritation

NH4+

NO2-AOB

Nitritation

NH4+

NO2-AOB

Anammox

N2

Anammox

N2O2O2

Aerobic

Anoxic

= 0.5-1.5

mg/L

MBBR

x AOB in biofilm = NO2- limitation

Updates on Ongoing Technology Development

IFAS 3X the loading rate of MBBR but requires a clarifier

BiofilmMedia

Liquid

Nitritation

NH4+

NO2-

AOB

Anammox

N2O2

AnoxicMedia

Liquid

Nitritation

NH4+

NO2-

AOB

Anammox

N2O2

Anoxic

< 0.5

mg/L

Flocs

(1-3 g/L)

AOB in flocs = less NO2- limitation

0

1

2

3

0 2 4 6 8

N-r

em

oval (g

N/m

2.d

)

N-NO2 (mg/L)

IFAS ANITA™Mox – Bench-scale

MBBR IFAS

0

2

4

6

8

10

0 5 10 15 20 25 30

N-r

em

oval (g

N/m

2.d

)N-NO2 (mg/L)

Higher N-removal rates with higher NO2 level

Higher NO2 level in IFAS





















ANITATM MOx MBBR

Principle One Step ANAMMOX®

NH4

+

NO2

-

NO3

-

N2

NH4

+

NH4

+

O2

Principle One Step ANAMMOX®

2 NH3

+ 1.7 O2 1.14 NO

2- + 0.86 NH

3 0.88 N

2+ 0.24 NO

3-

Benefits of AOB-ANAMMOX granules?

• Robust - less sensitive to NO2-N inhibition and scaling

• Compact reactors

• Responds well to peak flows and loads

• Better separation from influent TSS

• Rapid settling velocities 5 – 10 m/h

Single-Stage ANAMMOX® Process

• Second generation design: Single Stage

− Both nitritation and Anammox reactions

− Air lift design initially used for aeration

− Gas/liquid/solids separation modules

• Controlled by:

− Continuous aeration

− DO adjusted to control NOB growth

− NO2 -N

− Hydrodynamic conditions select for

granulated sludge; lighter flocculated solids

not retained

• Granular biomass beneficial

− Operate solids at 10 to 15 g/L

− Diffusion resistance reduces sensitivity to

inhibition e.g. NO2 > 30 mg/L

~1mm Dia. Granules

~1mm Dia. Granules

Upflow Granulation Process: ANAMMOX®

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

27-Mar 16-Apr 6-May 26-May 15-Jun

ammonia load (kg/m³.d)

ammonia removed (kg/m³.d)• Rendac Performance

‒ Biofuels Plant (The Netherlands)

‒ Design load: 5,700 kg-N/d

‒ Startup 1 month with seeding

• Removal rates 1.4 – 1.6 kg N/m3/d

‒ 85% TN removal

• ANAMMOX® systems in China

successfully treating loads up

to 11,000 kg-N/d at design

loading of 2 kg-N/m3/d

• Energy consumption reported

to be 1.0 to 1.5 kW-hr/kg-N-

removed

Comparative Summary of Deammonification Processes

Suspended

SBR

(DEMON®)

Attached

MBBR

(ANITATM Mox)

Granular

Single-Stage

(ANAMMOX®)

Volumetric

Loading Rateskg N

/m3/day0.7 – 1.2

0.7 – 1.2

IFAS > 3.2 ?1.4 – 2.0

Performance

TN Removal%

~90% NH3-N

~85% TN

~90% NH3-N

~85% TN

~90% NH3-N

~85% TN

Energy Demand kW hrs/

kg N

removed1.0 – 1.3 1.2 – 1.75 1.0 – 1.3

Startup 1-2 months with

cyclone &

30% seeding

~4 mo w/

10% seeding

1 mo

w/ seeding

Sensitivity /

Flexibility

pH & DO control

NO2 < 5 mg/l

Pre-settling

DO control

Tolerates elevated

DO & NO2 well

DO control

Tolerates

elevated NO2

• Pros: energy efficient; widely used; very small footprint

• Cons: operator attention, NO2-N tolerance

Sidestream Deammonification - Proven Technology

Second Generation(building on lessons learned

from first applications)

First Applications

First

Demonstration

Pilot

Final Generation

Mature Technology

ANAMMOX

DEMON

IFAS AnitaMox

MBBR

AnitaMox

Terra-NClear Green

Sidestream Treatment

70 operational facilities

Proven process, sustainable, small footprint, cost-effective

60% less oxygen

90% less carbon

50% less alkalinity

40% less biomass

“Future Ready for New Frontiers”

- Mainstream Deammonification

Strass WWTP, Austria-Cold Climate Full Scale Mainstream Deammonification Demonstration

– First cold climate demonstration

– A-B type plant

– Temperature 10-12°C range

– A-Stage - ½ day SRT high rate

activated sludge with 65% carbon

capture for energy recovery

– B-Stage - carousel type aeration

tank providing high DO transient

anoxia (DO 0-1.7 mg/L).

– Sidestream DEMON for AOB &

Anammox bio-augmentation

– Cyclones for mainstream Anammox

retention

0

5

10

15

20

25

1-Dec 11-Dec 21-Dec 31-Dec 10-Jan 20-Jan 30-Jan

2010/2011 NO3-N effluent 2010/2011 NO2-N effluent 2011/2012 NO3-N effluent 2011/2012 NO2-N effluent

nit

roge

n c

on

cent

rati

on

(mg

N/L

)

0

5

10

15

20

25

1-Dec 31-Dec 30-Jan 29-Feb 30-Mar 29-Apr 29-May

2010/2011 NO3-N effluent 2010/2011 NO2-N effluent 2011/2012 NO3-N effluent 2011/2012 NO2-N effluent

nit

rog

en

co

nce

ntr

ati

on

(m

g N

/L)

Conventional BNR

Effluent Nitrogen 2010

Mainstream Deammonification

Effluent Nitrogen 2011

Full Scale Cold Climate Success - Strass WWTP, Austria

Deammonification performance was better and more reliable than

the conventional BNR process resulting in less nitrogen to the river

Mainstream Granular Deammonification Performance at Dokhaven

WWTP, Rotterdam at Cold Temperatures

• At temperatures down to 12 C,

removal rates sustained at

80% to 100% of that expected

at 20C

• Need good DO control and

control of BOD and TSS from

the A-Stage

• High BOD and TSS

loading will

encourage growth of

NOB and other

microorganisms that

hamper selection of

AOB on the granule

surface

Key Findings of Mainstream Granular ANAMMOX

3-year Demonstration

– NOB activity was successfully suppressed and controlled.

– High removal rates were achieved with a low NOB activity.

– Long term process stability remains a challenge; fluctuations in influent BOD

are an important factor.

– Fluctuating BOD loads can be better handled in a plug flow reactor, instead of

the mixed tank reactor as used in the demonstration project.

– New full scale demonstration planned for China

Conclusions

• Sidestream deammonification is a proven, mature

technology.

• Mainstream deammonification strategy is promising.

• When upgrading your plant, consider incorporating

sidestream deammonification along with flexibility for

mainstream in the future.

Thank you!

[email protected]

(616) 574-8321

November 8, 2017

deammonification for cost-effective sidestream …€¦ · deammonification for cost-effective...

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