MWEA Process Seminar- Case Studies on Bio-P Implementation … - Bio P_MWEA Process... · 2015. 11....

Post on 22-Aug-2020

1 views 0 download

transcript

MWEA Process Seminar-

Case Studies on Bio-P Implementation

Eagle Eye Banquet Facility

Bath, MI

November 12, 2015

The Kalamazoo River is an impaired

water body. The Kalamazoo Water

Reclamation Plant (KWRP) is a

Signatory to the voluntary Lake Allegan /

Kalamazoo River Phosphorus TMDL

(Total Maximum Daily Loading)

agreement since 1997. TMDL season is

April through September.

TMDL Phosphorus

Reduction Strategy

Early 1980’s- Phosphorus Removal by

Alum Precipitation

1997- KWRP Signs on to Kalamazoo/Lake

Allegan TMDL - Point Source Discharger

2001-2002 KWRP Piloted Ferric Chloride

1997-2005 Soluble Phosphorus Increased

- Annual average Up 44%

- Daily Loading over 1,000 lbs/day

- Peak loading exceeding 3,100 lbs/day

November 2005 to May 2006

- Worked with Industrial Users

- Source Reduction

June 2006

- Largest Phosphorus Discharger

Changed Process

- Switched to Sulfuric from Phosphoric

- 32% Decrease Soluble Phosphorus

Expected an Improved Nutrient Balance

Strategy Modifications

2006-2008

- Decreased BOD Loadings

- Largest SIU Decreased by 70%.

The Nutrient Balance Did Not Improve

March 2007

- KWRP & Tetra Tech Conduct Pilot Test

- Enhanced Biological Phosphorus

Removal (EBPR) in twin 40,000 gpd Units

- Modified Aeration Tanks to 3 anaerobic

and 1 swing zone

- Seeded pilot trains - KWRP mixed liquor

- Within 30 days EBPR train working

- EBPR @ 0.33 mg/L Psol

- Activated Sludge @ 1.62 mg/L Psol

May to June 2007

- EBPR Train Struggle

- EBPR Psol @ 1.95 mg/L

- Activated Sludge @ 2.73 mg/L

- Tetra Tech Evaluated Conditions

June 2007

- Primary Thickener Fermentation

- Increased Volatile Fatty Acids (VFA)

- Better Food Source for Phosphorus

Accumulating Organisms (PAO)

2007- October 2009

- Piloted various configurations

- Piloted Biological Nutrient Removal

(BNR) with anoxic zones and mixed

liquor recirculation

2008-2010

- Fermenting and VFA Production

Improved KWRP Phosphorus Removal

- Nutrient Balance Improved

- Fermenting 0.93 & w/o 1.14

2008-2010

- Created Favorable BNR Conditions

KWRP to Enhance Phosphorus

Removal

- Treatability Study Conducted

- Design & Modified Secondary

Treatment to Incorporate BNR

2011

- Retrofitted 9 Aeration Basins

- 3 Zone A2O BNR system

- Membrane Fine Bubble Diffusers

- Energy Efficient Blowers

- Total Project Cost - $ 7,556,000.

Anaerobic Zone – Complete Absence of Oxygen

Anoxic Zone – No Free Oxygen but as Oxidized

Nitrogen Compounds

Recirculation Pump

Aerobic Zone with Fine Bubble Diffusers

TMDL Phosphorus Strategy Results

Strategy

Influent Soluble

Phosphorus

lbs/day

Chemical

Addition

gpd

Effluent Total

Phosphorus

lbs/day

1997-2001 Chemical Addition - Alum

TMDL – 8 of 30 months 809

1861

All Mon/yr 114

2002-2006

Chemical Addition - Ferric

Industrial Source Psol Reduction

TMDL – 22 of 30 months

858 1498

All Mon/yr 78

2007-2010

Chemical Addition - Ferric Due to

BOD Reduction - Piloted BNR,

Fermented Primary Solids

TMDL- 17 of 24 months

558 428

9 Mon/yr 89

2011-2015 BNR Implementation

TMDL – 26 of 30 months 520

144

5 Mon/yr

56

BNR Benefits

Lower Chemical Costs - reduced feed

Lower Hauling Costs - less chemical sludge

Better Settling Sludge - PAO / exopolymers

Lower Disinfection Costs - less chloramines

Nitrate Recirculation - oxygen recovery 17%

Challenges / Surprises

Fermenting - VFA production (carbon source)

Temperature - high temp struggle (predictable)

Filamentous Organisms - M. Parvicella

Dewatering - reduced cake solids (slight)

Nitrates - hinder performance

Questions ???