Design Considerations - GHD...• Conventional activated sludge SVI correlations may not be appropriate for design/evaluation • Designs should be based on site -specific column tests,

Design Considerationsfor BioMag® FacilitiesThor Young | Principal Manager

Introduction Overview of BioMag® Process

GHD @ WEFTEC 2014

Waste Activated Sludge (WAS)

Clarifier Reactor Influent Effluent Mixed Liquor

Return Activated Sludge (RAS)

MLSS, mg/L 3,000 Loading Rate

Capacity

Biological Floc

Conventional Activated Sludge Process Solids loading rate < clarifier capacity

GHD @ WEFTEC 2014

MLSS, mg/L 3,000





Capacity…increase MLSS… …clarifier at capacity To achieve better treatment…

(BNR/ENR)

GHD @ WEFTEC 2014





CapacityFurther increase MLSS… …clarifier overloaded MLSS, mg/L 4,000

…solids in effluent

GHD @ WEFTEC 2014

BallastedWasteActivatedSludge(B-WAS)

VirginMagnetite

WasteActivatedSludge(WAS)

ClarifierReactorInfluent EffluentMixed Liquor

Return Activated Sludge (RAS)MagSilo Ballasted Return Activated Sludge (B-RAS)

Ballasted

MLSS, mg/L6,000 Loading Rate

Capacity

MagnetiteFeedSystem

…improved settling …high-quality effluent

…enhanced clarifier capacity

…wasted magnetite?

GHD @ WEFTEC 2014

WAS)

VirginMagnetite

(WAS)((WAS)(B(WAS)B-(WAS)-WAS)(WAS)WAS)

ClarifierEffluent

MagSilo

MLSS, mg/LLoading Rate

Capacity

MagnetiteFeedSystem

…high-quality effluent

…enhanced clarifier capacity

Magnetite

MLSS, mg/L6,000

GHD @ WEFTEC 2014

Shear Mill Ballasted Waste Activated Sludge (B-WAS)

Virgin Magnetite


Mag Silo Ballasted Return Activated Sludge (B-RAS)

Ballasted


Capacity

Recovered Magnetite

Waste Activated Sludge (WAS) Magnetic Recovery

Drum

Magnetite Recovery System

GHD @ WEFTEC 2014

Ballasted Waste Activated Sludge (B-WAS)

Virgin Magnetite



Ballasted

Recovered Magnetite


Drum

Ballast Mix Tank

Shear Mill

Magnetite Recovery System

Ballasted Mixed Liquor

Ballast Mix Tank

Ballasted Waste Activated Sludge (B-WAS)

Virgin Magnetite

Clarifier Reactor Influent Effluent


Recovered Magnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Overview Preliminary Treatment

Biological Processes

Aeration and Mixing

Secondary Clarifiers

Chemical Addition

Solids Wasting

Magnetite Recovery

Magnetite Feed

Pipes and Open Channels

Solids Treatment

BallastedMixed Liquor

BallastMix Tank


VirginMagnetite

ClarifierReactorInfluent Effluent

MagSilo Ballasted Return Activated Sludge (B-RAS)

RecoveredMagnetite

Waste Activated Sludge (WAS)MagneticRecovery

Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank


VirginMagnetite

Ballasted Return Activated Sludge (B-RAS)

RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated


ClarifierClarifierReactorReactorEffluent

Ballasted Return Activated Sludge (B RAS)

Reactor

Ballasted Return Activated Sludge (BBallasted Return Activated Sludge (B

Preliminary Treatment

Influent

Primary Clarifier 2-mm Fine Screen

2-mm Fine Screen (B-WAS)


Equipment needed to protect magnetite recovery equipment from rags, debris, fibrous materials


BallastMix Tank


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RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank


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RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated


ClarifierClarifierEffluentMixed Liquor


ReactorInfluent

BioMag compatible with:• Conventional aeration• Extended aeration• 4-Stage Bardenpho• 5-Stage Bardenpho• Modified Ludzack-Ettinger (MLE)• Sequencing Batch ReactorsTypical MLSS concentrations:• Conventional: 2,000 – 4,000 mg/L• BioMag: 5,000 – 8,000 mg/L (excl. magnetite)

– Double or triple biological treatment capacity within existing tank volume

• "Charging" system with magnetite takes weeks


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014


BallastMix Tank


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ClarifierClarifierReactorReactorInfluent Effluent


RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated


Microbial Kinetics• No negative impacts to nitrification/denitrification

shown by McConnell et al. (2010)• Improved simultaneous nitrification-denitrification

observed by Jimenez et al. (2013), possibly from– Biofilm formed on magnetite– Magnetite facilitates electron transfer

• Further investigation needed on SND kinetics

Filamentous Growth• Magnetite weighs down filamentous floc and

improves clarifier performance• Additional measures required in severe cases


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank


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RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated



Aeration & Mixing

Reactor

& Mixing

Influent

Aeration Considerations:• Increased MLSS and

biomass will decreasealpha (oxygen transfer coefficient)

• Aeration system will need to be evaluated• Magnetite does not increase alpha

(independent testing by McKean et al., 2013)

BioMag has been tested with:• Coarse-bubble diffusers,• Fine-bubble diffusers,• Jet aeration, and• Mixers with air sparge

2003 Krampe & Krauth. Oxygen transfer into activated sludge with high MLSS concentrations

α @ 3,000 mg/L ≈ 0.8

α @ 8,000 mg/L ≈ 0.5


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank


VirginMagnetite


RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated



Aeration & Mixing

Reactor

& Mixing

Influent

Mixing Considerations:• Maintain ballasted

solids in suspension– Supplemental mixing for aerated tanks– May need to upsize mixers in unaerated tanks– Watch out in corners and behind mixers

Design Guidelines• HP per gallon varies based on tank geometry• Minimum velocity of 1.5 fps along tank floor• CFD has been attempted with mixed results

Moody et al. (2011). Beyond Desktop Evaluation: Key Design Criteriafor Mixing and Settling of Magnetite-Impregnated Mixed Liquor


BallastMix Tank


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RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank


VirginMagnetite


RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated



Aeration & Mixing

Reactor

& Mixing

Influent

Recommendations:• Systems that allow for

independent mixing and aeration preferred(e.g. jet aeration systems, mixers with air sparge)

• Involve mixer manufacturer early in design• Consider a low-DO zone to promote SND


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank


VirginMagnetite


RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated

ClarifierClarifierEffluent

Chemical Addition

InfluentClarifierReactor

pH, Alkalinity

• Magnetite does notimpact alkalinity or pH

• Metal salts required for enhanced TP removal– Effluent TP < 0.2 mg/L without filtration– Compatible with alum, ferric, PACl– Magnetite does not impact chemical stoichiometry

• Polymer required upstream of secondary clarifier– Feed rate = ½–2 mg/L x (Plant + RAS flow)– Size system to provide dose at peak flows– Avoid insufficient or excessive mixing– Dry feed more cost-effective for large facilities

Metal Salt Polymer


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank


VirginMagnetite


RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated

EffluentEffluent


Mixed LiquorBallasted

Mixed LiquorReactorReactor

Influent


Clarifier

25

4035

100

Average Peak0

20

40

60

80

100

Sol

ids

Load

ing

Rat

e, lb

/d/ft

²

• Peak solids loading increased by 150%

• SLR does not include weight of magnetite

• Hydraulic loading rate has not been a limiting factor to date; limits unknown


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014


RAS)

Shear Mill

Ballasted Return Activated Sludge (B

Shear Mill

Mag

Waste Activated

Mag

EffluentEffluent



Mixed LiquorReactorReactor

Influent

Ballasted Return Activated Sludge (BBallasted Return Activated Sludge (B RAS)-

ClarifierDesign Guidelines• Conventional activated sludge SVI correlations may not

be appropriate for design/evaluation• Designs should be based on site-specific column tests,

pilots, or consultation with system supplier• Loading rates on previous slide may be used as guide• No impact on mechanisms (negligible load increase)

Additional Considerations• BioMag is well-suited for sludge blanket level detectors• Tested on circular and rectangular clarifiers• Suction manifold clarifiers headers recommended• Special considerations needed for peripheral feed


VirginBallast

Mix TankMagnetite

RecoveredMagnetite

MagneticRecoverySludge (WAS) Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated

Ballasted Return Activated Sludge (Bbe appropriate for design/evaluationbe appropriate for design/evaluationMagbe appropriate for design/evaluationMagbe appropriate for design/evaluationbe appropriate for design/evaluationbe appropriate for design/evaluation

•Silo•SiloDesigns should be based on siteDesigns should be based on siteDesigns should be based on siteDesigns should be based on siteDesigns should be based on siteDesigns should be based on siteBallasted Return Activated Sludge (BDesigns should be based on siteBallasted Return Activated Sludge (BDesigns should be based on siteDesigns should be based on siteSiloDesigns should be based on siteSiloDesigns should be based on siteDesigns should be based on siteDesigns should be based on siteDesigns should be based on siteBallasted Return Activated Sludge (BDesigns should be based on siteBallasted Return Activated Sludge (BBallasted Return Activated Sludge (B-Ballasted Return Activated Sludge (Bspecific column tests, specific column tests, specific column tests, specific column tests, Ballasted Return Activated Sludge (Bspecific column tests, Ballasted Return Activated Sludge (BBallasted Return Activated Sludge (Bspecific column tests, Ballasted Return Activated Sludge (Bpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplierpilots, or consultation with system supplier

• LLLoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideVirginoading rates on previous slide may be used as guideVirginoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideoading rates on previous slide may be used as guideVirginoading rates on previous slide may be used as guideVirginoading rates on previous slide may be used as guideoading rates on previous slide may be used as guide

• No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)Ballast

No impact on mechanisms (negligible load increase)Ballast

No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)VirginNo impact on mechanisms (negligible load increase)VirginMagnetiteNo impact on mechanisms (negligible load increase)MagnetiteNo impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)No impact on mechanisms (negligible load increase)VirginNo impact on mechanisms (negligible load increase)VirginMagnetiteNo impact on mechanisms (negligible load increase)MagnetiteNo impact on mechanisms (negligible load increase)

Additional ConsiderationsAdditional ConsiderationsAdditional ConsiderationsAdditional ConsiderationsAdditional ConsiderationsAdditional Considerations• BioMagBioMag is well-suited for sludge blanket level detectorssuited for sludge blanket level detectorsRecoveredsuited for sludge blanket level detectorsRecoveredsuited for sludge blanket level detectorssuited for sludge blanket level detectorssuited for sludge blanket level detectorsShear Mill

suited for sludge blanket level detectorsShear Mill• Tested on circular and rectangular clarifiersTested on circular and rectangular clarifiersTested on circular and rectangular clarifiersMagnetiteTested on circular and rectangular clarifiersMagnetiteTested on circular and rectangular clarifiersTested on circular and rectangular clarifiersTested on circular and rectangular clarifiersTested on circular and rectangular clarifiersTested on circular and rectangular clarifiersTested on circular and rectangular clarifiersTested on circular and rectangular clarifiers

• Suction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiersSuction manifold clarifiers headers recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedMagneticheaders recommendedMagneticheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommendedheaders recommended•Waste Activated•Waste ActivatedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedWaste ActivatedSpecial considerations needed for peripheral feedWaste Activated Sludge (WAS)Special considerations needed for peripheral feedSludge (WAS)Special considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedRecoverySpecial considerations needed for peripheral feedRecoveryDrumSpecial considerations needed for peripheral feedDrumSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedSpecial considerations needed for peripheral feedWaste ActivatedSpecial considerations needed for peripheral feedWaste Activated

1995 Daigger. Development of Refined Clarifier Operating Diagrams Using an Updated Settling Characteristics Database


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank

Magnetite

RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated



Solids Wasting


BallastVirginMagnetite

ReactorReactorInfluent


Shear Mill

RAS)Ballasted Return Activated Sludge (B-RAS)Ballasted Return Activated Sludge (BBallasted Return Activated Sludge (BBallasted Return Activated Sludge (B RAS)Ballasted Return Activated Sludge (B

Design Considerations• Don't include magnetite in SRT calculations• Consider different options for wasting

– Clarifier underflow (B-RAS)


12,000 – 16,000mg/L TSS

Avoid progressive cavity pumps


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank

Magnetite

RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated


Solids Wasting




Shear Mill



Mixed LiquorMixed LiquorMixed LiquorMixed LiquorMixed LiquorMixed LiquorMixed LiquorDesign Considerations• Don't include magnetite in SRT calculations• Consider different options for wasting

– Clarifier underflow (B-RAS)– Classifying selector (surface wasting)

• Target foam-causing organisms• Increased flow to recovery equipment


12,000 – 16,000mg/L TSS6,000 – 8,000 mg/L TSS


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

BallastMix Tank

Magnetite

RecoveredMagnetite


Drum

Shear Mill

VirginMagnetite

MagSilo

Waste Activated


Solids Wasting






Mixed LiquorMixed LiquorMixed LiquorMixed LiquorMixed LiquorMixed LiquorMixed LiquorDesign Considerations• Don't include magnetite in SRT calculations• Consider different options for wasting

– Clarifier underflow (B-RAS)– Classifying selector (surface wasting)

• Target foam-causing organisms• Increased flow to recovery equipment

– Classifying selector to gravity thickener• Target foam-causing organisms• Reduced flow to recovery equipment• Storage capacity for operational flexibility• HRT allows polymer to biodegrade

• Consider providing flexibility to use various means


Thickener

Shear Mill

ThickenedB-WAS

6,000 – 8,000 mg/L TSS

1-5% solids


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014


BallastMix Tank

VirginMagnetite



Mix Tank

Ballasted

Solids Wasting

Further Considerations• Not all B-WAS is wasted (biological floc attached to recovered magnetite)• Keep in mind when sizing B-WAS pumps and magnetite recovery system

Assuming95% magnetite capture efficiency and 25% biological solids return rate…

RecoveredMagnetite


20,000 gal/day1,000 lb/day MLSS1,000 lb/day magnetite

50 gal/day250 lb/day MLSS950 lb/day magnetite

19,950 gal/day750 lb/day MLSS

50 lb/day magnetite


B-WASRecovered MagnetiteWAS


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Magnetite Recovery




Shear Mill

MagneticRecovery

Drum

BallastMix Tank

VirginMagnetiteMagnetite

Sludge (WAS)Waste Activated Sludge (WAS)


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Magnetite Recovery

Shear Mill

Shear Mills• Improves magnetite recovery efficiency,

particularly at high flow and load conditions• High electrical load

– Operators have to weigh cost of energy use with cost of reduced magnetite recovery

• Yearly blade replacement, depending on use• Variable speed drives to run at constant torque• Should be near Magnetic Recovery Drums• Loud! Consider siting in basement

GHD @ WEFTEC 2014

Magnetite Recovery




MagSilo Ballasted Return Activated Sludge (B

Shear MillShear MillShear Mill

Mix Tank

RecoveredMagnetite


Drum

Shear MillShear MillShear MillBallastedWasteActivatedSludge(B-WAS)

Shear MillsShear Mills•• Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency, Improves magnetite recovery efficiency,

particularly at high flow and load conditionsparticularly at high flow and load conditionsparticularly at high flow and load conditionsparticularly at high flow and load conditionsparticularly at high flow and load conditionsparticularly at high flow and load conditionsparticularly at high flow and load conditionsMagparticularly at high flow and load conditionsMagparticularly at high flow and load conditionsparticularly at high flow and load conditionsparticularly at high flow and load conditions•Silo•SiloHigh electrical loadHigh electrical loadHigh electrical loadHigh electrical loadSiloHigh electrical loadSiloHigh electrical loadHigh electrical loadHigh electrical load

– Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use Operators have to weigh cost of energy use with cost of reduced magnetite recoverywith cost of reduced magnetite recoverywith cost of reduced magnetite recoverywith cost of reduced magnetite recoverywith cost of reduced magnetite recovery

Virginwith cost of reduced magnetite recovery

Virginwith cost of reduced magnetite recoverywith cost of reduced magnetite recoverywith cost of reduced magnetite recoverywith cost of reduced magnetite recovery

• Yearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useBallast

Yearly blade replacement, depending on useBallast

Yearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useVirginYearly blade replacement, depending on useVirginMagnetiteYearly blade replacement, depending on useMagnetiteYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on useYearly blade replacement, depending on use• Variable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueMix TankVariable speed drives to run at constant torqueMix TankVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueMix TankVariable speed drives to run at constant torqueMix TankVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueMix TankVariable speed drives to run at constant torqueMix TankVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torqueVariable speed drives to run at constant torque• Should be near Magnetic Recovery DrumsShould be near Magnetic Recovery DrumsShould be near Magnetic Recovery DrumsShould be near Magnetic Recovery DrumsShould be near Magnetic Recovery DrumsShould be near Magnetic Recovery DrumsShould be near Magnetic Recovery DrumsShould be near Magnetic Recovery DrumsShould be near Magnetic Recovery Drums• Loud! Consider siting in basementLoud! Consider siting in basementRecoveredLoud! Consider siting in basementRecoveredLoud! Consider siting in basementLoud! Consider siting in basementLoud! Consider siting in basement


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

MagneticRecovery

Drum

Magnetic Recovery Drums• Retrieves magnetite from B-WAS• Permanent magnet—not an electro-magnet• Flow meters and valves to evenly distribute flow• Hydraulic and solids loading rates

– Provided by manufacturer– Consider all sludge wasting options– Consider biological solids capture rate

• Variable speed drives to adjust rotation speed• Continuous operation recommended• Wet environment

Magnetite Recovery

MagnetiteMagnetite

Sludge (WAS)

GHD @ WEFTEC 2014

MagneticRecovery

Drum


Mix Tank

VirginMagnetite


MagSilo Ballasted Return Activated Sludge (B

Recovered Shear MillMagnetite

Sludge (WAS)

Magnetite


Magnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery DrumsMagnetic Recovery Drums•• Retrieves magnetite from BRetrieves magnetite from BRetrieves magnetite from BRetrieves magnetite from BRetrieves magnetite from BRetrieves magnetite from BRetrieves magnetite from BRetrieves magnetite from B--WASWASWASWASWASWASWASWASWASWASWASWASWAS•Mag•MagPermanent Permanent MagPermanent MagPermanent magnetmagnetmagnetmagnetmagnetmagnet—not an not an electroelectro-magnetmagnet•Silo•SiloFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowSiloFlow meters and valves to evenly distribute flowSiloFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowFlow meters and valves to evenly distribute flowBallasted Return Activated Sludge (BFlow meters and valves to evenly distribute flowBallasted Return Activated Sludge (B

•• Hydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading ratesHydraulic and solids loading rates––Virgin–VirginProvided by manufacturerProvided by manufacturerProvided by manufacturerProvided by manufacturerProvided by manufacturerProvided by manufacturerProvided by manufacturerProvided by manufacturerVirginProvided by manufacturerVirgin––– Consider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsBallastConsider all sludge wasting optionsBallastConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsMagnetiteConsider all sludge wasting optionsMagnetiteConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting optionsConsider all sludge wasting options– Consider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateMix TankConsider biological solids capture rateMix TankConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rateConsider biological solids capture rate

• Variable speed drives to speed drives to speed drives to speed drives to speed drives to speed drives to adjust rotation speed• Continuous operation Continuous operation RecoveredContinuous operation RecoveredContinuous operation Continuous operation Continuous operation Continuous operation recommendedRecoveredrecommendedRecovered• Wet environmentWet environmentWet environmentWet environment

Magnetite Recovery

FM

M


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014




MagnetiteVirginMagnetite

Silo

Waste Activated

Recovered WasteActivatedSludge(B-WAS)

RecoveredMagnetite


Drum

Shear MillRecoveredMagnetite

Sludge (WAS)

Magnetite Recovery

BallastMix Tank

Ballasted Return Activated Sludge (BBallasted Return Activated Sludge (B

Recovered

Ballasted Return Activated Sludge (BBallasted Return Activated Sludge (BBallasted Return Activated Sludge (B

BallastedWaste


Ballast Mix Tank• Blends magnetite into mixed liquor• Pump or gravity flow to reactor distribution box• Arrangements for multiple drums

B-RAS (100-200 gpm)


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Magnetite Feed

Magnetite Feed System• Storage: magnetite silo (30-day storage)

– Small installations may use skid hopper• Conveyance: pneumatic system

– Air compressor, dryer, and conveyor– Storage silo should be near ballast mix tank

• For long distances:– Water eductor and carrier fluid may be required

VirginMagnetite

MagSilo

Air Compressor

Air Dryer

Air Compressor

CONVEYOR

GHD @ WEFTEC 2014

Influent

RecoveredMagnetite


Magnetite Feed


BallastMix Tank

ClarifierClarifierReactorInfluent Effluent


Recovered

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– Small installations may use skid hopperSmall installations may use skid hopper• Conveyance: pneumatic systemConveyance: pneumatic systemConveyance: pneumatic systemConveyance: pneumatic systemConveyance: pneumatic systemConveyance: pneumatic systemConveyance: pneumatic systemConveyance: pneumatic systemBallasted Return Activated Sludge (BConveyance: pneumatic systemBallasted Return Activated Sludge (B

– Air compressor, dryer, and conveyorAir compressor, dryer, and conveyor– Storage silo should be near ballast mix tank

Ballast•Ballast For long distances:For long distances:For long distances:For long distances:–– Water Water Water Water Water Water

VirginVirginVirginMagnetiteMagnetiteMagnetiteMagnetiteMagnetiteMagnetite

MagSilo

Air Compressor

Air Dryer

Air Compressor

CONVEYORCONVEYORCONVEYORCONVEYORCONVEYORCONVEYORCONVEYORCONVEYORCONVEYORCONVEYOR


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

Redundancy and Emergency Operations

• Magnetite recovery equipment not required to meet treatment requirements

• Shear Mills– Not critical, may be bypassed– May be shut off during low flows

• Magnetic Recovery Drums– Redundancy recommended but not required– Many small facilities only have one unit

• Ballast Mix Tank– Mixer should be running at all times– Provide a spare mixer or gearbox/motor

• Magnetite Feed System– May be taken out of service for a few days– Standby air compressor & dryer optional


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Pipes and Open Channels


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Design considerations:• Velocities for pipes and open channels:

– 1.5 feet per second– 2 fps for re-suspension of settled magnetite– Consider startup and diurnal low flows

• Avoid low points in gravity pipes• Provide fillets and sloped floors for channels• Run pumps at high speed to flush pipes

– Automatic program– Particularly recommended for RAS pumps

• Provide mixers for distribution boxes– VFDs to allow for speed/power optimization


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Solids Handling and Treatment


BallastMix Tank

BallastedWasteActivatedSludge(B WAS)

VirginMagnetite



RecoveredMagnetite

Magnetic

Shear Mill

(B-WAS)MagneticRecoveryDrum

GHD @ WEFTEC 2014

Design considerations for solids treatment and handling processes• Expect a amount of magnetite in solids process• No impact on treatment and stabilization processes

– No issues anticipated with obtaining Class A biosolids• Residual magnetite may improve gravity thickener performance

Sludge (WAS)


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014


BallastMix Tank


VirginMagnetite



RecoveredMagnetite


Drum

Shear Mill

GHD @ WEFTEC 2014

Installations

Notes: Partial installation and pilot list provided by Evoqua Water Technologies, July 2014. Startup year for facilities currently under construction are estimated based on construction schedule.

Facility Name Location Startup Year Pilot History Average Flow,mgdLong Trail Brewing Company VT 2008 No pilot 0.013

Allenstown WWTF NH 2011 No pilot 1.3

Sturbridge WWTF MA 2012 2007 1.3

Upper Gwynedd WWTP PA 2014 2009 3.0

Smithsburg WWTP MD 2014 (est.) 2013 0.3

Easterly WWTP MA 2014 (est.) No pilot 5.5

Mystic WPCF CT 2014 (est.) 2009 1.4

Marlay-Taylor WWTP MD 2014 (est.) No pilot 6.0

Phillipsburg WWTP NJ 2015 (est.) No pilot 5.4

Front Royal WWTP VA 2016 (est.) No pilot 5.3

Taneytown WWTP MD In design 2010 5.0

Opequon/Hedgesville WWTF WV In design 2011 1.6

Kemptville WPCP Ontario In design 2013 3.1

Winebrenner WWTP MD In design 2009 2.2

Thank you

Documents

Design Considerations - GHD...• Conventional activated sludge SVI correlations may not be appropriate for design/evaluation • Designs should be based on site -specific column tests,