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Aerobic Digestion for the 21 st Century
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Page 1: Aerobic Digestion for the 21 Century · Aerobic Digestion is a process to: 1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid ...

Aerobic Digestion for the 21st Century

Page 2: Aerobic Digestion for the 21 Century · Aerobic Digestion is a process to: 1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid ...

Presentation Overview

About Aerobic DigestionAerobic Digestion ImprovementsAerobic Digestion in the Real World

2

Page 3: Aerobic Digestion for the 21 Century · Aerobic Digestion is a process to: 1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid ...

Digestion Expertise

3

WEFTEC 1997 ‐ 2001

VOL III 1999WORKSHOPDIGESTIONAEROBIC

Fine Tuningthe Controlled

Aerobic DigestionProcess

Class B

Of Meeting

While Digesting

Thicker Sludges

The Challenge

VOL I 1997

WORKSHOPDIGESTION

AEROBIC

CD-ROM

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Digestion Expertise

4

MOP 11 Operation of Municipal WWTP

Volume III:             

Solids Processes

Chapter 31: 

Aerobic Digestion

Author: 

Elena Bailey

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Digestion Expertise

5

MOP No. 8 5th Ed., 2009 Design of Municipal WWTPs

Volume III: 

Solids Processing and Management

Chapter 25:  Stabilization

Section 3 : Aerobic Digestion

Author:     Miguel  Vera

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About Aerobic Digestion

6

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What is Aerobic Digestion?

Aerobic Digestion is a process to:

1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid process but without new food they use their own biomass (endogenous respiration).

2. Stabilize the sludge so that it is safer for human contact, does not attract vermin (vectors), and odors are reduced.

7

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When is Aerobic Digestiontypically used?

1. When it is required by local regulatory agencies2. When the facility will be land applying their 

biosolids and needs to meet Class B requirements.3. When the facility wants to reduce the volume of 

sludge for final disposal4. When there are concerns about odors5. When there is no primary sludge (think BNR)

8

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Pluses and minuses of Aerobic Digestion

Pluses1. Inherently safer than anaerobic digestion2. Lower capital cost compared to anaerobic digestion3. Ease of operationMinuses1. Higher energy costs2. Temperature sensitive

9

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10

Aerobic Digestion Chemistry

Aerobic Digestion is a biological process similar to Activated Sludge.  

Activated Sludge = GrowthAerobic Digestion = Decay

Process control is required to maintain healthy biomass

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11

Biological Processes

1. Digestion:C5H7NO2 + 5O2 = 4CO2 + H2O + (NH4HCO3)Biomass  Ammonium Carbonate

2. Nitrification:NH4

+ + 2O2 = H2O + 2H+ + NO3‐

Ammonia                 Acid Nitrate

3. Digestion with Nitrification:C5H7NO2 + 7O2 = 5CO2 + 3H2O + HNO3Biomass  Nitric Acid

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12

Biological Processes

4. Digestion with Nitrification:C5H7NO2 + 7O2 = 5CO2 + 3H2O + HNO3Biomass Nitric Acid

5. Denitrification:C5H7NO2 + 4NO3

‐ + H2O = NH4+ + 5HCO3

‐ + 2N2Biomass Nitrate            Ammonia                 N Gas

Alkalinity

6. Complete Nitrification / Denitrification:C5H7NO2 + 5.75O2 = 5CO2 + 3.5H2O  + 0.5N2Biomass  N Gas

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Factors affecting the rate of digestion:

1. Temperature 

2. pH

3. Stability of the sludge

4. Biological diversity

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Traditional Digester DesignPrior to Class B Requirement

10 – 20 Days SRT (M&E, 1991)

Mixing Air ‐ 30 scfm/1,000 cf

No Performance Requirements

14

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503 Regs Change the Game

15

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Aerobic Digestion – Regulatory Requirements40 CFR Part 5031. Class B with respect to Pathogens:•60 Days @ 15 C or 40 Days @ 20 C

OR•Pathogens ≤ 2,000,000 CFU

2. Class B with respect to Vector Attraction Reduction•Volatile Solids Reduction ≥ 38%    

OR•SOUR ≤ 1.5 mg/L O2

16

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Aerobic Digestion – Regulatory Requirements (cont.)

17

0%

10%

20%

30%

40%

50%

60%

VS

S D

estru

ctio

n (%

)

0 200 400 600 800 1000 1200 1400 1600 1800 2000

Temp-SRT (deg. C-day)

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18

Aerobic Digestion Chemistry

18% Oxygen Savings:

3. Digestion with Nitrification:C5H7NO2 + 7O2 = 5CO2 + 3H2O + HNO3

Versus

6. Complete Nitrification / Denitrification:C5H7NO2 + 5.75O2 = 5CO2 + 3.5H2O  + 0.5N2

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19

Aerobic Digestion Chemistry

pH Cycle:

1. Digestion: (pH UP)C5H7NO2 + 5O2 = 4CO2 + H2O + NH4

+ + HCO3‐

2. Nitrification: (pH DOWN)NH4

+ + 2O2 = H2O + 2H+ + NO3‐

4. Denitrification: (pH UP)C5H7NO2 + 4NO3

‐ + H2O = NH4+ + 5HCO3

‐ + 2N2

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Aerobic Digestion Chemistry

Nitrogen Cycle:

1. Digestion:C5H7NO2 + 5O2 = 4CO2 + H2O + NH4

+ + HCO3‐

2. Nitrification: NH4

+ + 2O2 = H2O + 2H+ + NO3‐

4. Denitrification:C5H7NO2 + 4NO3

‐ + H2O = NH4+ + 5HCO3

‐ + 2N2

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Aerobic Digestion Temperature

• Optimum Range: 20°C – 30°C

• Rate (10°C)   ½ Rate (20°C)

• Nitrification stops at  5°C

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Techniques to Improve ProcessPerformance

22

1. Series or Batch Operation 2. Sludge Thickening3. Aerobic & Anoxic Operation4. Temperature Control5. Operational Flexibility

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1. Series / Batch Operation

23

Advantages:

• Reduces short‐circuiting of partially digested sludge

• Requires 50% less volume to achieve same volatile solids reduction

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Series / Batch Operation

Clyde, OH       2.5 MGD  WWTP

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2. Thickening

25

Advantages:

• Smaller digesters

• Less digested sludge

• Higher sludge temperature

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Thickening

0

0.5

1

1.5

2

2.5

3/24/2004 4/3/2004 4/13/2004 4/23/2004 5/3/2004 5/13/2004 5/23/2004 6/2/2004 6/12/2004 6/22/2004 7/2/2004 7/12/2004

Perc

ent S

olid

s

Date of Measurement

Total Digester Solids Concentration

Hauling Cost Savings

40%

Hauling Cost Savings

60%

Hauling Cost Savings

60%

Previous Maximum Concentration = 1.1%

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3. Aerobic / Anoxic Operation

27

Advantages:

• Reduce O2 requirements by 18%

• Preserve alkalinity

• Reduce total nitrogen

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Aerobic / Anoxic Operation

Bellville, TX 0.95 MGD WWTP

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Effect of AO/AX on VSR

Ref.: I. Al‐Ghusain, et. al., Environmental Technology, Vol. 25, 2004

T = 20C, SRT = 10 d

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4. Temperature Control

30

Advantages:• Increased digestion rate

• Maintains healthy biomass

• Provides consistent operation and performance year around

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Effect of Temp on VSR

Ref.: I. Al‐Ghusain, et. al., Environmental Technology, Vol. 25, 2004

SRT = 10 dAnoxic Cycle = 8 hr

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32

Designs should incorporate the following as much as possible:

• Ability to control sludge thickness in digesters

• Ability to control air flow to each basin

• Ability to monitor pH, DO, & T

5.  Flexibility

Page 33: Aerobic Digestion for the 21 Century · Aerobic Digestion is a process to: 1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid ...

Aerobic Digestion Improvements

33

Page 34: Aerobic Digestion for the 21 Century · Aerobic Digestion is a process to: 1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid ...

Effects of Thickening on Aeration

1. Lowering of alpha values

2. Mixing is as important as aeration

3. Seasonal thinningmay be necessary

6/13/2014

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Product Features

35

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Above Water Orificing

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Ease of Access

37

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The Diffuser in Action

38

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Improved Mixing Ability

39

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40

Oxygen Transfer Efficiency

4%

6%

8%

10%

12%

14%

16%

6 8 10 12 14 16 18 20

Oxy

gen

Tran

sfer

Eff

ecien

cy

Submergence Depth (ft)

Diffuser Performance CurvesTransMax and MS

TransMaxMS

Airflow Rate:15-25 scfm/diffuser

TM

MS

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Tank Geometry

Abilities of the single drop diffuser must be kept in mind

1. Oxygen transfer efficiency improves with depth

2. Mixing ability increases with depth as well

3. Varying sidewater depths can be problematic for shear tubes, blowers, and header arrangements 

6/13/2014

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G‐TAD Process

42

G‐TADstands for:

Gravity Thickened Aerobic Digestion

Page 43: Aerobic Digestion for the 21 Century · Aerobic Digestion is a process to: 1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid ...

Gravity Thickener

43

Page 44: Aerobic Digestion for the 21 Century · Aerobic Digestion is a process to: 1. Reduce the quantity of sludge for disposal. Bacteria continue metabolism as they do in the liquid ...

Aerobic Digester

44

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Working Together

45

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G‐TAD Process Flow

Pre‐Mix

1

1. Waste sludge is pumped into Pre‐mix

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G‐TAD Process Flow

Pre‐Mix

GravityThickener

2

1

2. Sludge flows into Gravity Thickener

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G‐TAD Process Flow

In‐LoopDigester

Pre‐Mix

GravityThickener

2

1

3

4

3. Thickened sludge airlifted into Digester4.  Nitrified sludge overflows into Pre‐mix

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G‐TAD Process Flow

In‐LoopDigester

Pre‐Mix

GravityThickener

2

1

3

4

5

6

5. Scum airlifted into Digester6. Supernatant returned to head of plant

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G‐TAD Process Flow

IsolatedDigester

In‐LoopDigester

Pre‐Mix

GravityThickener

2

1

3

4

5

7 6

7. Class B sludge removed for disposal

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G‐TAD Batch Operating Cycle

DIGESTER #1 CYCLE

DIGESTER #2 CYCLE

Feed StageDay 1 ‐ 2        Fill Digester #1   Day 3 ‐ 14      In‐loop Thickening

Batch StageDay 15 ‐ 26     Isolation          Day 27 ‐ 28     Draw down

Batch StageDay 1 ‐ 12          IsolationDay 13 ‐ 14        Draw Down

Feed StageDay 15 ‐ 16  Fill Digester #2Day 17 ‐ 28  In‐loop Thickening

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G‐TAD Process

52

G‐TAD Installation ReferencesLocation

Design Flow

Plant Configuration

Commission Date

Stockbridge, GA 1.5 MGD SBR 2002

Belleville, TX 0.95 MGD Complete Mix 2002

Clermont, FL 2.0 MGD Oxidation Ditch 2002

Gardner, KS 2.5 MGD Oxidation Ditch 2003

Woodland, WA 1.3 MGD SBR 2003

Myrtle Creek, OR 2.9 MGD Oxidation Ditch 2004

Shelton, WA 2.5 MGD Oxidation Ditch 2004

Amherst, OH 6.1 MGD Oxidation Ditch 2004

Blue Mtn. Lake, PA 0.14 MGD RBC 2004

Brenham, TX 3.55 MGD Complete Mix 2004

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M‐TAD Process

53

M‐TADstands for:

Mechanical Thickened Aerobic Digestion

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M‐TAD Process

54

The PAD‐M process is…An enhanced digestion process to achieve guaranteed Class B biosolids

• with conventional equipment• in a reduced volume, • using less energy.

REDUCE VOLUME

VOLATILE SOLIDS 

REDUCTION

ENSURESPATHOGENREDUCTION

MECHANICAL THICKENER

AIR AIR AIR

OPTIONAL STORAGE

DIGESTER 1 DIGESTER 2

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M‐TAD Process

55

Thickened Sludge

Raw SludgeMechanical Thickener

Filtrate

Aerobic Digester No. 1Aerobic Digester No. 2 Aerobic Digester No. 3

Optional Cover for Temp. Ctrl. Class B Digested Sludge

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Diffusers with Shear Tubes

6/13/2014

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Diffusers with Draft Tube

6/13/2014

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M‐TAD Process

58

LocationDesign Flow

Plant Configuration

Thickening Method

Clyde, OH 1.9 Oxidation Ditch GBT

Los Lunas, NM 0.7 Extended Aer. GBT

Paris, IL 1.4 1° & 2° Sludge GBT/BFP

Myrtle Beach, SC 12.6 Ext. Aer. & RBC RDT

Sanford, FL 7.2 Extended Aer. GBT

Lynden, WA 1.8 Oxidation Ditch RDT

Warsaw, IN 3.9 Oxidation Ditch GBT

Burlington, IA 7.6 C.A.S. DAF

Ideal for:Larger WWTPs  

Conversion of existing anaerobic and holding tanks 

M‐ ITADnstallation References

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Bellefonte M‐TAD Process

59

Rotating Biological Contactor followed by M‐TAD Process

Engineer: Nittany EngineeringHistory:• Objective was to produce Class B 

biosolids for land application• Retrofit of equalization basin into 

three aerobic digesters in series.• PAD‐M process designed for solids 

loading increase from 2 MGD to 3.2 MGD.

• Thickening to 4% solids was required to meet Class B criteria without having to build additional tanks at 3.2 MGD flow.

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Bellefonte M‐TAD Process

60

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Bellefonte M‐TAD Process

61

Longer SRT from thickening complimented by outstanding temperature control results in 

outstanding VS reduction

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Bellefonte M‐TAD Process

62

First Quarter 2010 Second Quarter 2010

Rep Number CFU/Dry Gram Rep Number CFU/Dry Gram

1 175 1 268

2 4,715 2 704

3 934 3 1,622

4 173 4 1,679

5 1,117 5 2,370

6 970 6 2,647

7 5,048 7 414

Geometric Mean 956 Geometric Mean 1,040

Third Quarter 2010 Fourth Quarter 2010

Rep Number CFU/Dry Gram Rep Number CFU/Dry Gram

1 2,360 1 268

2 2,785 2 83

3 164 3 380

4 976 4 269

5 179 5 633

6 602 6 10,400

7 <59 7 <57

Geometric Mean 480 Geometric Mean 364

Pathogen Data

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Mem‐TAD Process

63

Mem‐TADstands for:

Membrane Thickened Aerobic Digestion

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Mem‐TAD Process

Combines a Membrane Thickening Tank with two Aerobic Digesters

Guaranteed Class B Biosolids

Capable of between 3% & 5% solids

No polymer required or attention to decanting

Continuous thickening ‐ independent of wasting schedule

Reuse quality permeate

64

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MEMBRANE TECHNOLOGY OVERVIEW

65

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Definitions

FLUX:  The rate of filtration per unit area of membrane material is called flux.

TMP:  The pressure difference across a membrane during filtration is called transmembrane pressure (TMP).

PERMEABILITY:  The ratio of flux to TMP is referred to as permeability.

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Pressure when permeate suspended ‐ Pressure when permeating time ‐ Head loss in piping (Friction , fittings, etc)=    TMP

Suction methodP

Constant Level

G

Constant discharge

FM

TMP

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Membrane Cartridges

Chlorinated Polyethylene membrane; ultrasonically welded to both sides of an ABS

plate

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Membrane Thickener Data

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• Nominal pore size 0.4 micron, effective pore size 0.1 micron

• Effective filtration area 8.6 ft2 to 15.1 ft² per cartridge

• MBT Design flux 5 gfd @ 20° C

• MBT Cross flow velocity is 2.25 ft / sec

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Submerged Membrane Unit (SMU)

Manifold

Membrane case

Membrane cartridges

Diffuser caseDiffuser

Tubes

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Physical ResponsibilityDesign of The Submerged Membrane Unit (SMU)

Acts like an air lift pump•Continuous Course bubbles at the bottom•Fully enclosed•Air scour in constant contact with membrane through full range of travel•Continuous movement of mixed liquor, keeps tank contents well mixed and in suspension

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Biofilm ‐ Basics

All submerged membranes have a biofilm.What is a biofilm?• A complex dynamic matrices comprised of microorganisms, EPS/SMP, non‐biological solids, substrates, metabolites, interior pores and channels

What do biofilms do?• Create a dense secondary membrane that can allow for enhanced nutrient removal and degradation of refractory organics

Why do we care?• Biofilms serve as the primary filter and represent a changing resistance to filtrate flow (affects plant ops.)

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Biofilm Conditions

Ideal Thick

Increased TMP

Non‐Uniform

Variable TMPStable TMP High TMP

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The Biofilm (A Dynamic Membrane)Permeate

MLSS + Air (Cross Flow)

Serves as primary filtering mechanism (0.1 m)

Biofilm control is key to membrane performance in mixed liquor (biohydraulics)

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Types of Membrane Fouling

adsorption pore clogging particle deposition

A: macromolecules on membrane matrixB: macromolecules (aggregates) and cell debrisC: not serious if cells alone; serious w/ interstices

filled by EPS (Extracellular Polymeric Substances)

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BiofoulingIn UF Membranes (Choi et. al., 2005)

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Biofilm Management

Air Scouring• The rise velocity of bubbles impacts shear force and boundary layer thickness

• Rise velocity is a function of flowrate, geometry and flow resistance 

• Intensity requirement is a function of deposition rate (flux) and fluid viscosity

• Defined air flow pathways promote even distribution• Turbulent velocity (slug flow) maximizes effect

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Air Scour

Ideal

Stable TMP (RC)

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How does SMU Air Scour work?

Continuous cross‐flow of mixed liquor and air maintains optimum biofilm thickness

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Chemical Cleaning (CIP)

Maintenance Cleaning• Intended to remove surface (biofilm or 

cake) fouling.1

• Does not involve taking tanks out of service for extended periods of time (~1‐4hr)

• Routine procedure• Can return to MBR filtration mode in 

~15 minutes

Recovery Cleaning• Intended to “dislodge particles 

from membrane microstructure.”1

• May take from >4‐24hrs.

• Requires that membranes be soaked in concentrated chemical solution.

• Generally a non‐routine procedure

1 Membrane Systems for Wastewater Treatment, WEF 2006.

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CIP Strategies

Enviroquip utilizes Maintenance Cleaning only (no Recovery Cleaning) to address irreversible fouling.

Operating at low TMPminimizes deep pore fouling and extends membrane service life.

High concentration, frequent dosing can impact sludge quality and increases TDS, making effluent less suitable as RO feed

Minimizing chemical exposure minimizes membrane deterioration and extends membrane service life.

Reducing downtime also reduces owner risk while improving system flexibility.

M

R

M

R = Recovery Cleaning (~24hr)

M = Maintenance Cleaning (~2hr)

Others

EQ

1 year

5.0

0.0

10.0

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Enviroquip Maintenance Clean

Control Valve

Pressure Regulator

Chemical Eductor

Stock Chemical Supply

Flowmeter

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CIP Cartridge Distribution

• Cleaning takes approximately 2‐4 hour / MBR basin, using a dilute solution of 0.5% Sodium Hypochlorite or Citric Acid

• In‐situ cleaning of membranes without draining MLSS• Chlorine dosage less than that typically used for 

filamentous microorganism control• No tank liners required

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86

-1.50

-1.00

-0.50

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4:48 7:12 9:36 12:00 14:24 16:48 19:12 21:36 0:00 2:24Time (min)

Line

Pre

ssur

e (p

sig)

Relaxation(King County DNR EW200 Pilot)

No Relax

Sample Date: 10/11/05

Avg. Gross Flux = 16.3 gfd1

Air Scour = 0.014 SCFM/ft2

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Minimum Maintenance Of Membrane Thickener 

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• Automated Diffuser Cleaning, approx. 30 min/day

• Membrane Relax, approx. 1min/10min

• Chemical Cleaning, in‐situ clean every 6 months, approx 2 hour duration

NO NEED TO DRAIN TANKS OR TAKE OUT OF SERVICE FOR CHEMICAL CLEANING!

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Mem‐TAD Process

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Digester 1

Digester 2

Anox. Basin

MBT

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SHOW ME THE BENEFITS

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Case Studies of Aerobic Digestion Processes with Membrane Thickening

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Dundee WWTP, Michigan

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MBR and Mem‐TAD 

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Dundee WWTP, Michigan

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Digester #1

Digester #2

MBT

Engineer: ArcadisHistory:• Objective was to reduce the hauling 

to 2 times per year. Tanks are designed to store 180 days at 3% solids.

• Operator friendly when compared to other systems.

• Enviroquip’s Aerobic Digestion experience rated higher when evaluated against other vendors/technologies.

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Membrane Thickener Tank

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Digester 1

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93

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Digester 2

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Dundee WWTP, Michigan

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Sep & Oct 2005 Operation

0

1

2

3

4

5

6

Date

% solids

WASMBT ThickenerDigester #1Digester #2

Thickening Performance

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Dundee WWTP, Michigan

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0

1

2

3

4

9/5 9/15 9/25 10/5 10/15

BODTSSNH3

MBT Permeate Results

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Dundee WWTP, Michigan

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January 2007 to June 2008 DataSustainable Permeate Quality 

before it’s blended with MBR effluent BOD: 1.12  mg/lTSS: 2.00  mg/lNH3‐N: 0.22  mg/lNO3‐N: 0.03  mg/l TP: 1.09  mg/l

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Dundee WWTP, Michigan Sludge Hauling Cost Summary 

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Years Gallons Hauled Dry Tons Yearly Cost

2004 (0.6 MGD SBR) 248,885 – Belt943,200 – Truck1,192,100 ‐ Total

22.67 – Belt99.39 – Truck122.06 ‐ Total

$16,850 – Belt$30,088 – Truck$46,938 ‐ Total

2005 (1.2 MGD MBR)MBT operational for2nd half of year only

572,400 – Belt432,000 – MBT1,004,400 ‐ Total

55.62 – Belt47.55 – MBT103.17 ‐ Total

$39,135 – Belt$14,623 – MBT$53,758 – Total

2006 887,400 ‐MBT 130.48 – MBT* $32,739 ‐MBT

Belt press was needed for years 2003 ‐05 due to lack of storage space.Sludge Hauling costs for first full year of operation of MBT in 2006 was $32,739 which is lower than the last 5 years

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99

McFarland Creek, OH MBR + Mem‐TAD

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SMUs Installed Directly in Digesters

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100

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McFarland Creek WWTP, Ohio 

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Membrane thickening at McFarland Creek WWTP was able to thicken up to 5% solids.  

0

10,000

20,000

30,000

40,000

50,000

60,000

11/29 1/18 3/9 4/28 6/17 8/6 9/25 11/14 1/3 2/22

TSS (

mg/

L)

Date

Thickening tank 2

Thickening tank 2

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Union Rome WWTP, OhioEngineer: CT Consultants

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MBR and Mem‐TAD 

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Union Rome WWTP, Ohio

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0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

Dec-09 Jan-10 Mar-10 May-10 Jun-10 Aug-10 Sep-10

Con

cent

ratio

n (%

)

Date

Union Rome WWTP Membrane Thickening TS Results

Effluent TSInfluent TS

The TS concentration was MORE THAN TRIPLED by thickening with membranes at Union Rome 

WWTP.  

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Union Rome WWTP, Ohio

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January 2010 to October 2010 Data

Sustainable Permeate Quality after it’s blended with MBR effluent 

BOD: <1.0  mg/lTSS: <1.0  mg/lNH3‐N: <0.1 mg/lTP: <5.0  mg/l

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Membrane Thickening

Combines a Membrane Thickening Tank with a Solids Holding Tank.

Thickening not Class B!

Capable of between 3% &  5% solids

No polymer required 

Continuous thickening ‐ independent of wasting schedule

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Membrane Thickening Process Flow Diagram

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WAS

To Hauling or Dewatering

Thickened Sludge Return

4Q Recycle

MBT SHT

Permeate

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Woodside NY – 0.30 MGD

Driver: Reduce Hauling costs

Retrofit system following Conventional Activated Sludge

Operational since Feb. 2008

Using Existing Tanks (2‐25’ dia. x 15’ deep)

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Woodside, NY

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109

Woodside MBT Compartment / SHT

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Woodside, NY Results

Thickening of CAS solids to 3.0 to 3.5% 

Reduced the number of trucks by Half in 2008Reduced amount of Nitrogen in the sludge and permeate

Low operator attendance required

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Eco‐MAT

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Operations: What don’t you do?

Start the unit up each day

Shut the unit down each day

Check the polymer system

Check the unit repeatedly throughout the day

Check the polymer system

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Operations: What do you do?

Collect daily process data

Perform visual inspection of system

Chemical clean membranes 3 – 4 times per year

Perform regularly scheduled preventative maintenance

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MBT – Aerobic Dig. InstallationsDate Plant City State Liquid Process MBT/ PAD-K

Jun-04 Dundee WWTP Dundee MI MBR PAD-KJun-04 Arlington WWTP Arlington WA SBR MBTJul-04 Troy WWTP Troy MO MBR PAD-KAug-04 McFarland Creek WWTP Chagrin Falls OH MBR PAD-KNov-04 Gnadenhutten WWTP Gnadenhutten OH MBR PAD-KApr-05 Delphos WWTP Delphos OH MBR StormmasterApr-05 Cottonwood WWTP Manor TX MBR PAD-KAug-05 Lewes WWTP Lewes DE MBR MBTNov-05 East Dundee WWTP East Dundee IL CAS PAD-KApr-06 Yakama IN Casino Toppenish WA MBR PAD-KMay-06 Woodside STP Yaphank NY CAS PAD-KMay-06 Stoutsville WWTP Stoutsville OH MBR MBTJun-06 North Lewisberg WWTP North Lewisberg OH MBR MBTJul-06 Harvest Monrovia Hunstville AL MBR MBTJul-06 Bob's Creek WWTP Lincoln County MO MBR PAD-KAug-06 Hamden WWTP Hamden OH MBR MBTAug-06 Shelton WWTP Shelton WA MBR MBTSep-06 Lake of the Pines WWTP Auburn CA MBR PAD-KNov-06 Concrete WWTP Concrete WA MBR PAD-KDec-06 Providence Estates O'Fallon MO MBR PAD-KFeb-07 Westford-Acton WWTP Acton MA MBR MBTApr-07 Winlock WWTP Winlock WA MBR PAD-KJun-07 Burwell Road WWTP Hunstville AL MBR MBTJun-07 Highland Lake Estates WWTP Monroe NY MBR MBTApr-08 Alpine WWTP Alpine WY MBR PAD-KJul-08 Union Rome WWTP Union Rome OH MBR PAD-KOct-09 C'oeur d'Alene Casino C'oeur d'Alene ID MBR PAD-KDec-09 Cayce WWTP Cayce SC OX PAD-K

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AirBeam Covers

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AirBeam® covers help to aid in temperature control and integrates Ovivo’s aeration equipment

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AirBeam with Diffusers

6/13/2014

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AirBeam Covers

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AirBeamComponents

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AirBeam Covers

6/13/2014

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AirBeam with Draft Tube

6/13/2014

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Is Aerobic Digestion Right for You

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Right for You?

Aerobic Digestion is very good for anyone who has a nutrient limit on their effluent

We are able to remove nitrogen (and phosphorus with the mem‐TAD) thus lowering the impact of recycle streams on the liquid process

Mem‐TAD systems can be fed around the clock, this means less of a shock on the liquid stream biomass

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Right for You?

Our products and systems (especially the membranes) are ideal for expanding existing capacity of treatment plants

This is a huge issue as towns and cities have to do more with less all the time

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Right for You?

Membrane products produce reuse quality effluentAs water becomes more and more valuable this feature is going to become more and more important for wastewater plants

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Right for You?

Coarse bubble diffusers work extremely well in deep tanks, always be on the lookout for a plant that has existing deep tanks and/or one looking to lower it’s blower power requirements.

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Thank You for your Time and Attention!

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