Fermentation Enhanced Nutrient Removalat Janesville WWTF WWOA – 46th Annual Conference

October 11, 2012

Presented by: Nathan Cassity, AECOMJoe Zakovec, Janesville Wastewater Utility

Presentation Outline

• Project background• BNR design• Startup and operation• Supplemental carbon pilot• What’s next?

Project Background

Project Background

• Current flow of 14 MGD• Serves population of 60,000• Biological phosphorus removal (BPR) first

incorporated 2001 to 2003– Anaerobic / Oxic (A/O) configuration– Included backup chemical P removal facilities– Influent lacked sufficient VFAs– Chemical polishing used off and on

Project Background

Mixing Basins

Aeration Basins

PE PERAS

Anaerobic AerobicMixed Liquor

2003 A/O Process Configuration

20% anaerobic volume

80% aerobic volume

Project Background

2003 A/O Process Configuration

Project Background

• 2010 – 2011 upgrade project– $32 million upgrade– Capacity increase to 20 MGD– Incorporated biological nutrient removal

(BNR)– New cogeneration facilities– Renovation of several 30+ year-old facilities

Biological Nutrient Removal Design

Biological Nutrient Removal Design

• Project goals:– Enhance biological phosphorus removal to

eliminate chemical polishing• Effluent phosphorus goal between 0.3 mg/L and

0.5 mg/L– Incorporate biological nitrogen removal

• Effluent nitrogen goal between 6 mg/L and 8 mg/L

• Resources utilized– BioWin computer simulations– AECOM Canada experts

Biological Nutrient Removal Design

• Process configuration– Anaerobic / Anoxic / Oxic (A2O)

Anaer. Anoxic Aerobic

RAS WAS

Influent EffluentMixed Mixed Aerated

Internal Nitrate Recycle

Biological Nutrient Removal Design

PE RAS

Anaerobic

Aerobic

Mixed Liquor2011 A2O Process Configuration

12% anaerobic volume21% anoxic volume67% aerobic volume

Anaerobic

Anaerobic Aerobic Aerobic

Anoxic

Anoxic

Swing

SwingAnoxic

Anoxic

Swing

Anoxic

Anoxic

Swing

Biological Nutrient Removal Design

2011 A2O Process Configuration

PE RAS

Anaerobic

Aerobic

Anaerobic

Anaerobic

Aerobic Aerobic

Anoxic

Anoxic

Swing

Swing

Anoxic

Anoxic

Swing

Anoxic

Anoxic

Swing

Biological Nutrient Removal Design

• Fermentation incorporated into design due to low wastewater strength– Primary sludge is pumped to the fermenters– Fermenters store and thicken the sludge– VFA production is based on time and temperature– Operation based on target SRT

FermentersOverflow(VFAs)

Primarysludge

Fermented primary sludge

Biological Nutrient Removal Design

Fermenter SRT vs VFA Production

0.0

50.0

100.0

150.0

200.0

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

time - days

mg/

L

Acetic Acid

• Overflow from fermenters provides the necessary VFA for biological phosphorus removal

• The remaining VFA flows into the anoxic zone for biological nitrogen removal

Biological Nutrient Removal Design

Anaer. Anoxic Aerobic

RAS WAS

Influent EffluentMixed Mixed Aerated

Internal Nitrate Recycle

Fermenter Overflow (VFAs)

Biological Nutrient Removal Design

Anaerobic Zones

Anoxic Zones Aerobic Zones

VFAs

Nitrate Recycle

Swing

Biological Nutrient Removal Design

• System components– Baffle walls

• Create boundaries for the environments• Minimize short-circuiting

Biological Nutrient Removal Design

• System components– Mixers

• Keep tankage completely mixed without aeration

Biological Nutrient Removal Design

• System components– Nitrate recycle pumps

• High flow, low head pumping between tankage

Biological Nutrient Removal Design

• System components– Swing zones – aeration can be turned on or

off

Startup and Operation

Startup and Operation

• BNR system overview

Fermenters

Anaerobic

Anoxic

Notconvertedyet

Aerobic

Startup and Operation

• Fermenters and anaerobic zones

Fermenter Overflow (VFAs)

Startup and Operation

• Fermenter overflow– Flow of 0.9 MGD– 7% of forward flow– Currently generating

1000 lbs/day VFA

Date Volatile Acids (mg/L)

01/03/12 10001/24/12 8702/14/12 12502/22/12 11502/28/12 21603/07/12 21803/14/12 18303/14/12 16303/21/12 6003/27/12 11804/04/12 7204/09/12 15004/18/12 12104/24/12 10505/04/12 139Average 132

Startup and Operation

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

5/17/2011 7/6/2011 8/25/2011 10/14/2011 12/3/2011 1/22/2012 3/12/2012

Efflue

nt Pho

spho

rus (mg/L)

Janesville Effluent Phosphorus

Start-up

Ethanol Waste Addition

Ethanol Waste Removal

Average 0.50 mg/L

Startup and Operation

• Biological Phosphorus Removal– Increase VFAs using fermentation

Fermenter Overflow (VFAs)

Total Phosphorus Average 0.09 mg/L

Total Nitrogen Average 5 mg/L

**Ethanol Plant Waste Being Received**

0

1

2

3

4

5

6/20/2012 6/30/2012 7/10/2012 7/20/2012 7/30/2012 8/9/2012 8/19/2012

Efflue

nt Pho

spho

rus (mg/L)

Janesville Effluent PhosphorusMost Recent Two Months

Startup and Operation

Total Phosphorus Average 0.35 mg/L

Total Phosphorus Average 0.50 mg/L

Startup and Operation

• Anoxic and aeration zones

0

2

4

6

8

10

12

14

16

5/27/11 7/16/11 9/4/11 10/24/11 12/13/11 2/1/12 3/22/12 5/11/12 6/30/12 8/19/12

Efflue

nt Nitrogen (m

g/L)

Janesville Effluent Total Nitrogen 2011 ‐ 2012

Startup and Operation

Start-upEthanol Waste Addition

Ethanol Waste Removal Average

7.0 mg/L Average 5.5 mg/L

Supplemental Carbon Pilot

Supplemental Carbon Pilot

• Pilot Project– Evaluate feeding supplemental carbon from

QLF Specialty Products • Liquid molasses blend product• 7.3 lbs COD per gallon (875,000 mg/L)

• Pilot Goal– Stabilize BPR performance near 0.10 mg/L

effluent total-P (no filters and no ferric chloride)

Supplemental Carbon Pilot

• QLF product fed into fermenters– Fermenters convert product to VFA’s– VFA loading in fermenter overflow increased

Fermenters

Overflow (VFAs) to Anaerobic Zones

Primarysludge

Fermented primary sludge

80 gpd QLF Feed(600 lb/d COD)

0

50

100

150

200

250

300

12/23/11 02/11/12 04/01/12 05/21/12 07/10/12 08/29/12

Volatile Acids (m

g/L)

Janesville Fermenter Overflow Volatile Acids

Supplemental Carbon Pilot

1000 lbs/day VFA

1600 lbs/day VFA

Started feeding 80gpd QLF Solution

Ave. temp. in July was 94°F

0

0.5

1

1.5

2

2.5

3

7/12/2012 7/22/2012 8/1/2012 8/11/2012 8/21/2012 8/31/2012 9/10/2012

Efflue

nt Pho

spho

rus (mg/L)

Janesville Effluent Phosphorus

Supplemental Carbon Pilot

Industrial Discharge?

Started feeding 80 gpd QLF Solution

0.10 mg/L P Average0.35 mg/L P Average

What’s Next?

What’s Next?

• 2012 Fall / Winter Activities– Continue supplemental carbon feed pilot– Continue BNR optimization study

• Analysis and adjustment of operating parameters• Stabilization of biological phosphorus removal

– Evaluate (based on above results) if TMDL P limits can be achieved without upgrades.

Fermentation Enhanced Nutrient Removalat Janesville WWTF WWOA – 46th Annual Conference

October 11, 2012

Presented by: Nathan Cassity, AECOMJoe Zakovec, Janesville Wastewater Utility