Use of anammox systems to reduce nutrient concentrations

Haydee De Clippeleir, PhD. Research Program manager

DC Water

outline

• Nutrient removal: 1.0 3.0 • Sidestream deammonification:

– Process level benefits – Global plant benefits – Technologies

• Mainstream deammonification: a new paradigm shift for the plant of the future

1 mole Ammonia (NH3 / NH4

+) ½ mole Nitrogen Gas

(N2 )

75% O2 (energy) 100% Alkalinity (caustic)

1 mole Nitrite (NO2

-)

Autotrophic Aerobic Environment

Heterotrophic Anoxic Environment

Ammonia Oxidizing Bacteria (AOB)

1 mole Nitrite (NO2

-)

60% Org C

25% O2 (energy)

1 mole Nitrate (NO3

-)

Nitrite Oxidizing Bacteria (NOB)

40% Org C

Nitrification/Denitrification (1.0)

Nitrite Shunt/SND (2.0)

1 mole Ammonia (NH3 / NH4

+) ½ mole Nitrogen Gas

(N2 )

75% O2 (energy) 100% Alkalinity (caustic)

1 mole Nitrite (NO2

-)

Autotrophic Aerobic Environment

Heterotrophic Anoxic Environment

Ammonia Oxidizing Bacteria (AOB)

Potential Advantages: • 25% reduction in oxygen demand (energy) • 40% reduction in carbon demand • 40% reduction in biomass production

1 mole Nitrite (NO2

-)

60% Org C

1 mole Ammonia (NH3 / NH4

+) ½ mole Nitrogen Gas (N2 )

+ a little bit of nitrate (NO3

-)

0.5 mole Nitrite (NO2

-)

Autotrophic Aerobic Environment

Autotrophic Anoxic Environment

37% O2 (energy) ~50% Alkalinity

AOB

Potential Advantages: • 63% reduction in oxygen demand (energy) • Nearly 100% reduction in carbon demand • 80% reduction in biomass production

Deammonification (3.0) Anaerobic Ammonia Oxidizing Bacteria = Anammox

Anammox Bacteria

Sidestream Deammonification

Influent Primary Clarifier

Aerobic

Secondary Clarifier Tertiary

Anaerobic Digestor Dewatering Deammonification

Primary Clarifier

Secondary Clarifier Tertiary

Anaerobic Digestor Dewatering

Centrate

• ~1% of Total Plant Influent Flow • ~20-40% of the Total Plant TN load • NH4 Concentration between 900 – 1,500 mg N/L • Alkalinity/NH4 ratio ≅ 3.5-4.0 • Temperature 30 - 38°C • Alkalinity insufficient for complete nitrification • Insufficient carbon for denitrification

7

What’s the benefit on process level?

• Remove ~20% of the N load to the plant by treating the centrate separately

• Do it with: – No chemicals (caustic & methanol) – < 40% of the energy cost – (as compared to traditional nitrification-denitrification)

• Business case is very good, particularly if existing tanks can be used

• Risks: – Requires robust process control, particularly during startup – Process has been adequately demonstrated – Seeding required for fast startup

8

What`s the benefit on plant level?

• Anammox technologies are they key to achieve energy autarky:

0

1

2

3

4

5

6

7

Nitrification / Denitrification

Nitritation / Denitritation

Deammonification(a.k.a. ANAMMOX)

kW-h

r / k

g N

rem

oved

Typical Energy Demand Ranges

anammox

Without anammox With anammox

-53 -27 Wh IE-1 d-1

One-Step systems • SBR + Hydrocyclone Granular Sludge

(DEMON) – Strass, Austria – Demon GmbH – World Water Works, Inc.

• Upflow Granular Sludge

(CANON/ANAMMOX) – Olburgen, Netherlands – Paques (NL)

• Biofilm process (MBBR-style)

– ANITA Mox – Malmo, Sweeden • AnoxKaldnes – Kruger - Veolia

– Deammon -- Hattingen, Germany & Stockholm • Purac

10

S-curve for anammox technology

Susanne Lackner, Eva M. Gilbert, Siegfried E. Vlaeminck, Adriano Joss, Harald Horn, Mark C.M. van Loosdrecht (2014), Full-scale Partial Nitritation/Anammox Experiences - an Application Survey, Water Research

25%

75%

>100 Full-scale Installations

Municipal

Industrial

Status in North America – DEMON – HRSD York River; Started October 2012; operating – ANITA Mox – HRSD James River; Started November 2013; operating

– DEMON – Harvest Power/Reedy Creek, FL; started January 2014; operating

– DEMON – Alexandria, VA; in construction – ANITA Mox – South Durham, NC; in construction – DEMON – Philadelphia, PA; 90% design – DEMON- Guelph, Ontario; in construction – DEMON – Pierce County, WA; pilot complete; in construction – DEMON – DC Water Blue Plains; in construction – ANITA Mox – Chicago Egan MWRDGC; in construction – DEMON – Greeley, CO, in construction

– DEMON – New York DEP; pilot completion recent – ANITA Mox – LA County San District; pilot completion recent – DEMON – Chicago Egan MWRDGC; pilot completion Feb 2013, in construction – ANITA Mox - Denver MWRD; pilot completion Feb 2013, in design – MBBR-style process – New York DEP; pilot ongoing

– DEMON - Alexandria, VA + DCWater pilot (no cyclone) – DEMON – New York DEP + DCWater pilot (no cyclone)

DEMON technology

14 14

Seed Sludge Aeration System

Instruments & Controls

Tank

Blowers Decanter Mixer Cyclone

DEMON® Process Components

DEMON® – Control Strategy

• SBR configuration – typically 6 or 8 hour cycle time • Last hour of cycle - settle and decant • During React Period – multiple mini-cycles (10-30 mins):

• Aerate • Mix/fill • Mix

• Aeration: • DO ~0.2-0.5 mg/L (PID control or constant airflow) • pH based aeration control

15

DEMON® Control Strategy - Anammox Enrichment

• Continual enrichment of anammox – Large excess of activity – Provides stability

• Ability to Washout NOB if proliferation occurs

Anammox returned to Process

AOB/NOB/OHO/debris

16

DEMON at HRSD York River (15 MGD)

DEMON

DENITE FILTERS

HEADWORKS

AERATION BASINS

ANAEROBIC DIGESTION

THICKENING

DEWATERING

Implementation of DEMON at York River

19

Hydrocyclone for Biomass Wasting

• Retain anammox in small dense granules • SRT of anammox granules >> SRT of AOB,

NOB, heterotrophs, debris • Create “washout” conditions for NOB • Control activity of AOB population

DEMON feed Overflow Underflow

DEMON @ DC Water

ANITA MOX technology

ANITA Mox Process Components

Aeration System Instrumentation Centrate Feed

Mixers and Heaters K5 Media Media Retention 23

• Centrate Feed Control • Aeration Control

– Continuous and Intermittent – Four Different Modes

1. Airflow (scfm) 2. Fixed DO 3. Floating DO 4. pH-based DO or airflow

– Low pH air shutoff and air-on setpoints

• Mixer Control

Process Control

HRSD James River Treatment Plant (20 MGD)

ANITA™Mox Sidestream Deammonification MBBR

Biofilm Growth

Seed media 2/26/14

New media 4/10/14

Seed media 4/10/14

New media 2/26/14

New media 7/15/14

Seed media 7/15/14

Seed media 12/12/13

New media 12/12/13

Lesson learned… • Both processes are robust • Neither are “plug and play” • Huge excess of anammox activity is

accumulated • Anammox are not the issue… • All issues/problems related to slowing of

AOB kinetics, requires additional aeration = NOB

• Operator training issues are no big deal (with good centrate equalization)

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What`s next?

29

Minimum energy consumption

for concentration and polishing of remaining C and

N

Maximum energy recovery from concentrated organics

anammox in side line anammox in main line -27 Wh IE-1 d-1 +10 Wh IE-1 d-1

anammox

Mainstream Deammonification

• Main driver @ DC Water: methanol savings 1. Treat part of N-load in sidestream deammonification

system 2. Obtain mainstream short-cut nitrogen in main line

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

$0

$2

$4

$6

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0% 20% 40% 60% 80% 100%

Payb

ack

Peri

od, Y

rs

Cost

Sav

ings

, $M

M/Y

r

Nitrogen Removed by Deammonification, %

Cost Savings

Carbon Electricity Total Cost Payback (Years)

Take homes

• Sidestream deammonification is established technology: – Small systems – No chemical costs – Energy savings

• Mainstream deammonification is the future towards energy autarky – Make right technology choice right now

Thanks

Haydee De Clippeleir, PhD. Haydee.declippeleir@dcwater.com

Research Program manager

DC Water