Aerobic Granular Sludge TechnologyBrian Bates

Channel Manager – AquaNereda®

Nereda® is a registered trademark of Royal HaskoningDHV.

Presentation Outline

• Aerobic Granular Sludge– History– Definition– Granule Formation– Process Description

• Process Comparison & Design Approach• Applications and Existing Installations• Solids Handling• Demonstration Facility / Pilot System• Summary

Aerobic Granular Sludge

Short History of Granules

• Prior to 1914: Biofilms• 1914: Activated sludge flocs• 1970’s: Anaerobic granules• 1990’s: Aerobic granules – RHDHV begins research• 2005: Construction of first full scale plant (industrial)• 2009: First full-scale plant (municipal) • 2016: Aqua Aerobic signs licensee agreement

• 2017: Aqua starts construction of first US demonstration plant (municipal)• 2017: Aqua builds first US Pilot Plant

Aerobic Granular Sludge Definition

“Granules making up aerobic granular activated sludge are to be understood as aggregates of microbial origin, which do not coagulate under reduced hydrodynamic shear, and which subsequently settle significantly faster than activated sludge flocs.”

• True microbial biomass• Minimum particle diameter of ~ 0.2 mm• AGS SVI5 is comparable to SVI30 of

typical activated sludge

Aerobic Granular Sludge Workshop 2004 Munich, Germany

Aerobic Granular SludgeConventional Activated Sludge vs Granule Structure

Source: engineersjournal.com

Conventional Activated Sludge Aerobic Granular Sludge

Aerobic Granular SludgeGranule Structure

Source: engineersjournal.com

Conventional Activated Sludge Mixed Microbial Community

Aerobic Granular Sludge Layered Microbial Community

PAODenitrifiersNitrifiers

AerobicAnoxicAnaerobic

Fish Analysis (Fluorescence In Situ Hybridization)

GAO FluoNit Cy3PAO Cy5

DO c

once

ntra

tion

Granule profile

AquaNereda® Granule

Aerobic Granular SludgeGranule Structure

Influence of DO

• Population distribution depends on DO

• Oxygen will be diffused in the granule

• Important to control the aerobic and anaerobic zone

Source: Mark van Loosdrecht Presentation WEFTEC 2016

O2 Concentration greater than 2 mg/l

O2 Concentration less than 0.5 mg/l

Aerobic Granular Sludge

Flocs

4 g/l

SVI5

Granules

8 g/l or more

SVI5

• Excellent Settling Properties• Increased MLSS

Granule FormationSelection Mechanisms

1) Hydraulic selection for fast settling particles2) Biology selection of EPS forming microorganisms

Selection MechanismsHydraulic Selection

• Selective wasting• Wash out smaller particles • Dense granules settle faster than CAS• Decrease settling time

transformation

• PAO’s form EPS• EPS is the chemical backbone of the granule• Dense bacterial gathering allow rapid settling

Selection MechanismsBiology Selection

AquaNereda Process

• Simple one-tank reactor concept• Timed cycle flexibility• Enhanced biological nutrient removal• No sludge recirculation

Grit Removal and Screening

Side StreamSludge Thickening

Pre-EQ (if needed)AGS

Reactors

Digester

Tertiary Filtration

and Disinfection(if needed)

Influent

AquaNereda® Process Flow

Effluent

AquaNereda® Process Cycle

AquaNereda® Process Cycle

Fill/Draw– Influent enters– Readily Available Carbon – High F/M– P-release– Effluent is displaced

AquaNereda® Process Cycle

React– Influent flow is terminated– Aerobic and anoxic conditions– Simultaneous nitrification/ denitrification – Nitrate transported by diffusion

into granule layers– P-Uptake– Automated control of the process

AquaNereda® Process Cycle

Settle– Influent flow still terminated – Granules separate from treated water– Sludge is wasted– Maintain desired concentration of biomass

…ready for a new cycle.

Advantages

• Excellent settling properties

• Up to 75 % smaller footprint

• Up to 50% energy savings

• Increased capacity

• Sustainable robust technology

• No support media

• No bulking sludge

• Chemical savings

Source: T.R. Devlin Aerobic Granular Sludge Presentation

AdvantagesUp to 75% Footprint Reduction

Garmerwolde, NL WWTP

35%

65%

Flow Split

~135’

~158’

https://www.royalhaskoningdhv.com

Frielas, Portugal WWTP

1 of 6 Aeration basins was retrofitted into a Nereda®

reactor

AdvantagesUp to 50% Energy Savings

Frielas WWTP, Portugal

Advantages Up to 50% Energy Savings

• High substrate and oxygen utilization rates

• Compact bioreactor

• Automated Control Process

Garmerwolde, NL WWTP

Advantages Up to 50% Energy Savings

Chemical Unit A/B system

2014 2015

Fe ton 119 130

Coagulant ton PEactive 39 30

Flocculant ton PEactive 8.4 7

PAC kgal 38 37

C-source kgal 189 159

Nereda

2014 2015 2016

25 8 0

- - -

- - -

- - -

- - -

AdvantagesSignificant Chemical Savings

Data from Garmerwolde, NL WWTP

In 2015, 8 ton of Fe was used during storm events.

In 2016, the operator better managed the system and used no Fe

AdvantagesProcess Robustness

• Robust during less favorable conditions:

• Salinity fluctuations• Chemical spikes• pH fluctuations• Load variations Activated sludge and

granular sludge with shock addition of 5,000 ppm NaCl after 5 min of settling

AGSCAS

AquaNereda®

Process Comparison & Design Approach

ComparisonAquaNereda® System

Single Tank Reactor DesignComparison to Typical Multi-Stage BNR System

SecondaryAerobic

1 Hr HRT

PrimaryAerobic

12-18 Hr HRT

AnaerobicReactor

2 Hr HRT

SecondaryAnoxic

2 Hr HRT

PrimaryAnoxic

2 Hr HRT

1Q1Q 3-5Q

Comparison5-Stage BNR System

RAS

ComparisonAquaNereda® System

Single Tank Reactor Design

Foot

prin

t

BNR SBR MBBR MBR

25%25%

45%50%

100%

ComparisonFootprint

Note: Ballasted Floc footprint will depend on Process retrofitted

Ballasted Floc

60% - 45%

Ener

gy

BNR SBR MBBR MBR

ComparisonEnergy

Ballasted Floc

40%

100%

65%50%

70%

Note: Ballasted Floc Energy consumption will depend on Process retrofitted

75% - 50%

Design Approach

Ideal Application

• Retrofit Applications - Any existing process- Higher flows and loads

• New construction• Limited footprint • Plant expansion• Upgrade to BNR requirements • Industrial plants

Application Guidelines

• Typically applied with flows greater than 1 MGD

• Tanks deeper than 18 ft ideal (as low as 15 ft possible)

• Required 6 mm perforated plate upstream screening

• Flexible basin geometry

Typical System Components

• Aeration system• Pumps• Valves• Internal process piping• Weir assembly• Instrumentation• Controls

Existing Installations40 Plants Worldwide!

Nereda® Plants Around the World

Vika, Ede (NL) 0.07 2005Cargill, Rotterdam (NL) 0.18 2006Smilde, Oosterwolde (NL) 0.13 2009STP Gansbaai (RSA) 1.3 2.5 2009STP Epe (NL) 2.1 10 2011STP Garmerwolde (NL) 7.9 25 2013STP Vroomshoop (NL) 0.40 1.3 2013STP Dinxperlo (NL) 0.82 3.6 2013STP Wemmershoek (RSA) 1.3 3.0 2013STP Frielas, Lisbon (PT) 3.2 11.7 2014STP Ryki (PL) 1.5 2.9 2015Westfort Meatproducts, IJsselstein (NL) 0.37 2.1 2015STP Clonakilty (IRL) 1.3 3.9 2015STP Carrigtwohill (IRL) 1.8 5.4 2015

Phase 1 17 29 2016Phase 2 23 39 2025

STP Kingaroy (AUS) 0.7 2.9 2016STP Simpelveld (NL) 1.0 6.0 2016STP Cork Lower Harbour (IRL) 4.8 12 2017

Start-up

STP Deodoro, Rio de Janeiro (BR)

Daily average flow (MGD)

Peak flow (MGD)Operational plants

Nereda® Plants Around the World

STP Jardim Novo, Rio Claro (BR) 6.4 11 2017STP Hartebeestfontein (RSA) 1.3 1.3 2017STP Ringsend, Dublin (IRL) 159 317 2021STP Highworth (UK) 0.45 1.2 2017STP Alpnach (CH) 3.7 12 2017STP Zutphen (NL) 2.7 3.5 2017STP Faro – Olhão (PT) 5.4 12 2018STP Utrecht (NL) 15 84 2018Plants under designSTP Österröd, Strömstad (S) 1.0 2.3 2017STP Tatu, Limeira (BR) 15 22 2017

Phase 1 5.0 8.2 2019Phase 2 6.6 11 2024Phase 1 29 54 2018Phase 2 41 76 2025Phase 1 6.0 12 2018Phase 2 18 35 2025

STP Kendal (UK) 6.9 11.1 2018STP Barston (UK) 5.8 9.0 2019STP Kloten (CH) 6.9 18 2019STP Tijuco Preto, Sumaré (BR) 0.005 0.009 2019STP Walsall Wood (UK) 1.9 4.1 tbdSTP Radcliffe (UK) 1.4 2.9 tbdSTP Breskens (NL) 0.92 6.3 2018STP Great Dunmow (UK) 0.50 1.3 2018

STP São Lourenço, Recife (BR)

Daily average flow (MGD)

Peak flow (MGD) Start-up Plants under construction

STP Jaboatão, Recife (BR)

STP Jardim São Paulo, Recife (BR)

Nereda® Plants Around the World

STP Utrecht (NL) 0.40 3.8 2014-2022

Anonymous Petrochemicals (NL) 2011-2017

STP Daldowie (UK) 43 60 2014-2017

STP Dalmarnock (UK) 36 46 2014-2017

Macclesfield (UK) 0.001 0.004 2017Newmarket (UK) 0.001 0.004 2017STP Sha Tin (HK) 0.26 2016

Daily average flow (MGD)

Peak flow (MGD) Start-upPilots and demo’s

Parameters Influent Effluent

BOD5 333 2TSS 341 5TN - 4TP 9.3 0.34

Epe, Netherlands 2011 Greenfield – 3 Reactors

FlowsAverage

Flow (MGD)Peak Flow

(MGD)

2.1 9.5

• First full scale municipal installation in the NL• Granulation occurred over winter months with water temp below 10 degrees C• Nereda reduced energy consumption by 40%

Epe, Netherlands 2011 Start- Up

Parameters Influent Effluent

BOD5 230 10TSS 264 12TN 70 3TP 10 1

Kingaroy , AustraliaGreenfield – 2 Reactors

FlowsAverage

Flow (MGD)Peak Flow

(MGD)

0.71 2.85

June 16 till February 17

Ringsend, Ireland, 2019Retrofit – Expansion and Upgrade

FlowsAverage

Flow (MGD)Peak Flow

(MGD)

159 314

• Retrofit SBR• To be built in stages • Handles high salinity• Increased MLSS to 8 g/l

• This plant demonstrates that there are not upper limits to increasing capacity

Rio de Janerio, Brazil, 2016Greenfield

Parameters Effluent

BOD5 25TSS 10NH4-N 1PO4-P 1.5

FlowsAverage

Flow (MGD)Peak Flow

(MGD)

22.8 38.8

Rio de Janerio, Brazil, 2016Greenfield

• Operational just prior to the start of the 2016 Olympic games

• 10 times the capacity of the original design

Solids Handling

Solids Handling• AGS produces more EPS, but the chain is different than CAS EPS*

• Characterized as Alginate Like Exopolysaccarides (ALE)**

• Unlike the slimy EPS found in CAS, ALE forms clumps

– Therefore, despite the increase in EPS, it does not negatively impact solids handling

*Lin et al., 2012, **Lin et al., 2010 Untreated AGS Sludge

Solids HandlingDinxperlo, NL

0.1 - 0.3%Total Solids

0.8 – 1.0%Total Solids

2.3 – 2.5%Total Solids

Courtesy of GEA

Digestion &

Solids HandlingDecanter Centrifuge Pilot Results

• AquaNereda 22% cake Polymer 17-20 #/DT *

• SBR 18-20% cake Polymer 25 #/DT

• CAS 18-22% cake Polymer 22-30 #/DT

*GEA pilot study in Dinxperlo, NLGEA CF4000 Pilot

AquaNereda®

Demonstration Facility

Aerobic Granular Sludge Demonstration Facility – Rockford, IL0.2 MGD AGS

Reactors

Process Building

Filters

Blowers

AquaNereda®

Reactor

Sludge Holding

Demonstration FacilityRockford, IL - 0.2 MGD AGS

Construction of a 0.2 MGD AquaNereda® reactor with associated pretreatment, instrumentation and mechanical equipment

AquaNereda®

Reactor

Sludge Holding

Demonstration Facility Objectives

• Quicker access for operators to visit than travelling to Europe• Granule formation to seed future plants• Use for future seminars

Pilot Plant

Aerobic Granular Sludge Pilot Plant #1

Aerobic Granular Sludge Pilot Plant

Aerobic Granular Sludge Pilot Plant #2

Aerobic Granular Sludge Pilot Plant #2

Aerobic Granular Sludge Pilot Plant #3

Compact, single reactor design

Summary

AquaNereda® Summary• AGS reduces footprint, increases capacity and reduces energy• Compact, sustainable, robust• Achieves BNR and Bio-P removal • Over 40 installations worldwide • Demo facility and pilot are resources to assist with implementation in

the U.S.

Questions?

Design Examples

Design ExampleGreenfield – Example #1

• 1.0 MGD equalized flow• Influent equalization • Excess flow diverted to existing ponds• Compared with Oxidation Ditch• (2) AquaNereda reactors 43 ft x 43 ft x 21 ft WL• Savings of over 50% on area

Future Treatment Plant Location

Design ExampleGreenfield – Example #1

Design ExampleGreenfield – Example #2

• Existing tricking filters• Upgrade to meet BNR• Comparing to flow-through activated sludge BNR process

Design ExampleGreenfield – Example #2• Design Flow = 46 MGD Avg / 65 MGD Max• AquaNereda reactors would fit in 3/4 of the aeration basins area• Recommend (6) reactors / volume = 2.2 MG each

Secondary Clarifier 1

Secondary Clarifier 2

Secondary Clarifier 3

Secondary Clarifier 4

Secondary Clarifier 5

Secondary Clarifier 6

BNR Reactors AquaNereda

Influent Equalization

Influent Equalization

Design ExampleRetrofit – Example #1

• 2.8 MGD Average Flow / 5.9 MGD Maximum Flow• (3) Existing SBR tanks 90 ft x 80 ft x 16.4 ft Water Level• Convert basins to AquaNereda 80 ft x 68 ft• Split 80 ft x 21 ft into ancillary basins

AquaNeredaReactor #1

AquaNeredaReactor #2

AquaNeredaReactor #3

Equalization and Sludge Basins

Design ExampleRetrofit – Example #2

• Existing two train system 4 MGD total (Ammonia only)• No additional land available• Retrofitting one of the trains to AquaNereda for 3.5 MGD / 7.2 MGD• Splitting tank into 2 AquaNereda reactors• AquaNereda designed for TN of 5 mg/l and TP of 1 mg/l

AquaNeredaReactors

Equalization Basin

AquaNereda® Summary

• Compared to other BNR Process– Smaller footprint– Energy savings

• Ideal for greenfield or retrofit• Nutrient removal• Fits any basin geometry