NYWEA ENERGY SPECIALTY CONFERENCE

November 20, 2014

Towards Net-Zero Energy in Wastewater Treatment

Demonstration of ClearCove’s Enhanced Primary Treatment Technology

Alex Wright, ClearCove Systems & Mark Greene, O’Brien & Gere

2

Enhanced Primary

Treatment

• Benefits– Divert digestible material

• from secondary treatment

• to anaerobic digestion

– Higher TSS and BOD removal

– Coagulant addition leads to phosphorus removal

• Key Impact Areas of Evaluation– Chemical costs

– Hydraulic profile

– Readily degradable organics for N-removal

11/20/2014

3

Demonstration• CCS EPT Pilot

• Anaerobic Digestion Pilots

• Biochemical Methane Potential Testing

11/20/2014

4

EPT Pilot • 20,000 gal/day• Equalizes the flow • Stops the Flow• Removes 100% of the grit • Removes 100% of the fibers• Settles the high value organics

– Phys/Chem: chemical dosing and gravity– Colloidal capture

• Filters the effluent – 50 micron screen– Membrane Operation Benefit

• Removes the sludge to a classifying press

– Removes additional digestible organics– Removes and dewaters gross matter

11/20/2014

5

EPT Pilot• Wastewater pumped from influent

channel of IAWWTF• Wastewater enters both sides of the

tanks through the Influent Feed Chamber.

• Grit and dense solids settle out• Wastewater flows over 70 degree

weirs into the main chamber of the tank where the lighter solids settle out

11/20/2014

6

EPT Pilot • Screen box is lowered into low BOD, low solids supernatant after the settling period

• Wastewater flows through the screen and down a central effluent hose

• 50 micron stainless steel screen

• Air scour to deflect any floating material from coming in contact with screen

11/20/2014

Ithaca Influent Wastewater

Ithaca NY Results ClearCove’sEPT Effluent

The Best Biomass gets destroyed!

Suspended “Fuel”

7

ClearCove Results

Ithaca Primary Effluent

11/20/2014

8

Sludge Classifying Press

• Sludge from the EPT unit is processed through SCP

• SCP “cleans” sludge, removing inorganic solids and releasing encased organics.

11/20/2104

9

Pilot Digesters • 4 Fixed Volume Reactors

– 300-gallon, cone bottom– 100-gallon operating volume

• Hydraulic Mixing• Heating using IAWWTF hot water• Data logging for biogas flow and

digester temperature• Biogas measurements taken every

10 seconds (over 1 million readings over the course of the project)

11/20/2104

10

Pilot Digesters • Four (4) Feed Tanks

• Hydraulic Mixing• Solenoid valve diversion

to digester• Feedstock transfer by

buckets

11/20/2104

11

BMP• Bioprocess Control

– Automatic Methane Potential Test System (AMPTS II)

• (15) 640 ml reactors including controls

• Used to validate and correlate the digester pilot data

11/20/2104

12

Results• CCS EPT Pilot

• Anaerobic Digestion Pilots

• Biochemical Methane Potential Testing

11/20/2014

1311/20/2104

EPT/SCP Pilot Flow Schematic

1411/20/2104

15

Mini-Digester Flow SchematicTwo test units and two control units

11/20/2104

1610/2/2014

1710/2/2014

18

Plant Impacts• CCS EPT Pilot

• Anaerobic Digestion Pilots

• Biochemical Methane Potential Testing

11/20/2014

1911/20/2104

2011/20/2104

Actiflo

BACKWASH

21

Chemical Impact

• Current use

– 400-500 GPD Ferric Chloride

• Actiflo process

• 700 GPD peak

– 50-100 GPD Ferrous Sulfate

• Headworks

• Estimated use with EPT

– 400 GPD Ferric Chloride

11/20/2104

22

Reduction in Aeration Electricity IAWWTF uses 9,400 kWh/day

Aeration accounts for 48% (submetering) 72% for BOD removal (O2 demand)

28% for nitrification (O2 demand)

BOD removal in existing aeration 5,960 lb/day, 3,275 kWh/day

Energy = 0.55 kWh/lbrem

BOD removal with EPT 2,290 lb/day, 0.55 kWh/lbrem

Energy = 1,260 kWh/day

11/20/2104

-62%

2311/20/2104

24

Volatile SolidsCurrent

11/20/2104

• Mass Balance• Thousand Lb/day

• Gravity Primary Clarifiers• 28% VS capture

• Gravity Thickener• 43% VS capture

• Thickened Solids• 67% primary

• 33% secondary

7.3

18.8

26.1 6.1

9.517.0 30.0

13.0

19.5

60,000 scfd

25

Volatile SolidsEPT

11/20/2104

• Mass Balance• Thousand Lb/day

• Enhanced Primary Clarifiers• 84% VS capture

• Gravity Thickener• 43% VS capture

• Thickened Solids• 82% primary

• 18% secondary

7.3

18.9

26.2 1.5

5.017.0 30.8

13.6

24.7

100,000 scfd

EPT

2611/20/2104

26%

-45%

2.4x

2711/20/2104

Energy Production Potential

2.4 times

4.Xtimes

28

EPT Demonstration

Summary

• Sufficient amount of data collected

• Pilot EPT: 84% TSS removal

67% BOD5 removal

76% TP removal

• Primary sludge fraction of digester feed

– 67% current

– 82% with EPT

11/20/2104

29

Digestion Demonstration

Summary

• BMP Results

– IAWWTF Primary Sludge• 4.4 scf methane per lb VS fed

– Enhanced Primary Sludge• 6.6 scf methane per lb VS fed

– Statistically different with 95% probability

11/20/2104

30

Digestion Demonstration

Summary

• Pilot Results

– IAWWTF Primary Sludge• 4.1 scf methane per lb VS fed

• 13.4 scf methane per lb VS destroyed

– Enhanced Primary Sludge• 8.3 scf methane per lb VS fed

• 28.4 scf methane per lb VS destroyed

– Statistically different with 95% probability

11/20/2104

31

IAWWTF Impacts Summary

• Secondary Treatment Costs

– Decrease by 62%

– Savings of approx. $125,000/year

• Methane Generation from Primary Sludge

– Increase by 2.4x

• $325,000/year in kWh value

– Optimized upside potential is 4.5x

• $625,000/year in kWh value

* CNG economic $ value would be ~2x

– Potential for greater amount• Improved thickening

11/20/2104

32

Thank you!

11/20/2104

Rethink. Reduce. Renew.

Alex Wright, awright@clearcovesystems.com, (585) 269-8176

Mark Greene, mark.greene@obg.com, (315) 956-6271