A Streamlined Approach to Multi Facility Master Planning with Triple Bottom Line Optimization Vera Gouchev, P.E. January 22, 2018 NEWEA 2018 Annual Conference and Exhibit

Outline

1.  Study Goals 2.  Current Operations

3.  State-of-Good-Repair 4.  5-Year Plan Approach

5.  Multi-Facility Planning Tool 6.  25-Year Plan Approach

7.  Conclusions and Next Steps 8.  Q+A

Westchester County, NY Water Resource Recovery Facilities (WRRFs)

§  7 WRRFs, 5 to 120 MGD §  Discharge effluent to

Hudson River and Long Island Sound

§  Produce 19,700 Dry Tons sludge annually

Study Goals •  Perform detailed assessment of current

operations, practices, and equipment •  Develop 5-Year and 25-Year plans to mitigate

future risks while balancing County priorities

Westchester County WRRFs: Residual Process Matrix

Facility Thickening Dewatering Digestion

New Rochelle (NR) 21 MGD + Mamaroneck (MM) 23 MGD

Port Chester (PC) 6 MGD + Blind Brook (BB) 5 MGD

Ossining (OS) 7 MGD

Peekskill (PK) 10 MGD

Yonkers Joint (YJ) 120 MGD

Residuals Asset Evaluation

•  Developed Capital Plan based on maintaining State of Good Repair (SOGR)

•  Evaluated 1,607 residuals assets •  SOGR 5-Year Plan = $3.2 million •  SOGR 25-Year Plan = $120-150 million

•  Of this total, $80-120 million related to digester tank refurbishments at YJ WRRF (may be partially offset by final 25-Year recommendation – will be discussed in upcoming slides)

Evaluation of Current Operations Energy Usage Profile •  Hazen’s Energy Efficiency Tool (HEET) used to determine

fraction of power used for solids handling operations across the seven facilities

Evaluation of Current Operations Operating Cost Analysis

Digests + Dewaters

Digests Dewaters

Thickens Thickens

•  Range - $191/DT to $650/DT •  Average - $241/DT

Evaluation of Current Operations Development of County-wide Mass Balance

seven seven

5-Year Improvement Planning

•  Find opportunities for low capital cost improvements

•  Reduce liquid sludge volume •  Provide foundation for future, larger-

scale improvement projects proposed in the 25-Year plan

Goals

5-Year Improvement Strategy Opportunity for Centralization

•  Combine treatment of sludge from four facilities (PK, OS, BB, and PC) at one facility (PK)

•  PK selected based on digester capacity and space availability

OS WRRF

PK WRRF Centralized Dewatering

PC WRRF

BB WRRF

WAS Thickened Sludge

Capital Improvements at PK •  Build Storage •  Enhance Digestion with

Combined Heat and Power and FOG

•  Rehab of Decommissioned Dewatering Facility

5-Year Plan – Mass Balance

5-Year Plan – Source of Savings Estimated $1.1 MM/yr savings with 5-Year Plan Improvements

25-Year Improvement Planning

•  Reduce wet mass •  Reduce dry mass •  Lower unit disposal Costs by achieving

Class A biosolids •  Increase biogas production for CHP

Goals

25 Year Plan –Technology Options

Thermal hydrolysis Thermo-chemical pretreatment Utrasonication Oxidation (chemical) Biological pretreatment

Pretreatment Technologies Dewatering Technologies

Post-dewatering Technologies

Energy Recovery

Stabilization Technologies Anaerobic Digestion (AD) HSOW Co-Digestion Acid-Gas Phased AD High Solids AD Temperature Phased AD (TPAD) Pasteurization Neutralizer Process

Belt Filter Press (BFP) Centrifuge Screw Press Rotary Fan Press Electro-Dewatering Geotextile Tube Dewatering

Thermal Drying Gasification (Thermochemical) Pyrolysis (Thermochemical) Plasma-Assisted Thermal Oxidation (Thermochemical) Chemical Drying (for High Quality Fertilizer Production) Composting

Combined Heat and Power Biogas for thermal energy Biogas for biofuels Biogas for pipeline injection

Nutrient Recovery Ammonia Recovery Struvite Crystallization

25 Year Plan – Shortlist Technology Options

Thermal hydrolysis Thermo-chemical pretreatment Utrasonication Oxidation (chemical) Biological pretreatment

Pretreatment Technologies Dewatering Technologies

Post-dewatering Technologies

Energy Recovery

Stabilization Technologies Anaerobic Digestion (AD) HSOW Co-Digestion Acid-Gas Phased AD High Solids AD Temperature Phased AD (TPAD) Pasteurization Neutralizer Process

Belt Filter Press (BFP) Centrifuge Screw Press Rotary Fan Press Electro-Dewatering Geotextile Tube Dewatering

Thermal Drying Gasification (Thermochemical) Pyrolysis (Thermochemical) Plasma-Assisted Thermal Oxidation (Thermochemical) Chemical Drying (for High Quality Fertilizer Production) Composting

Combined Heat and Power Biogas for thermal energy Biogas for biofuels Biogas for pipeline injection

Nutrient Recovery Ammonia Recovery Struvite Crystallization

Multi-Facility Planning Tool

COST AND MASS BALANCE

Multi-Facility Planning Tool

Multi-Facility Planning Tool

Triple Bottom Line Results Output

Parameter Dry Tons per Year Processed Total Annual O+M Costs Range Estimated Capital Cost Annual O+M Cost Savings Range Estimated Payback Time Unit Processing Cost $/DT Total Wet Tons per Year Disposed Total Dry Tons per Year Disposed Estimated YJ Ammonia Load from Dewatering Estimated PK Ammonia Load from Dewatering Carbon Footprint Additional FTEs Required Trucks per Day at YJ

Priority Matching

35% 25% 20% 20%

Available Marks

Future Risk Mitigation Future Risk

Strategy and Rank

Stabilization Requirements

Loss of Class B Biosolids

Disposal Options

Sustainability Mandates

Nutrients in Dewatering

Recycle

YJ TPAD 1st

++ ++ ++ -

YJ Co-Digestion + PK Central Drying

2nd

++ ++ + 0

YJ Central Hydrolysis

3rd ++ ++ + - -

SustainabilityMandates,(2)LossofClassBBiosolidsDisposalOp;ons,(3)Stabiliza;onRequirements,and(4)FutureNutrientLimits

Sensitivity Analysis – Total Unit Costs

Baseline Class B Disposal Cost

$75/WT

Existing

5-Year Plan (Centralized Dewatering)

25-Year Plan (Centralized Class A Biosolids)

[VALUE]/DT

[VALUE]/DT

$0

$200

$400

[VALUE]/DT

[VALUE]/DT

$0

$200

$400

[VALUE]/DT

[VALUE]/DT

$0 $100 $200 $300 $400

Future Class B Disposal Cost

$150/WT

25 Year Plan Strategy Reduces Wet Mass

Reduces Dry Mass

Lower Unit

Disposal Cost

(Class A)

IncreasesBiogas $

Five Year Plan - PK Central Dewatering + Co-Digestion PK Central Drying YJ Central Hydrolysis YJ Temperature Phased Anaerobic Digestion YJ Co-Digestion YJ + PK Hydrolysis PK Central Drying + YJ Co-Digestion YJ Struvite Recovery *

Reduces Wet Mass

Reduces Dry Mass

Lower Unit Disposal

Cost (Class A)

IncreasesBiogas $

•  Transform YJ into a Centralized Class A biosolids facility by converting existing digesters to Temperature Phased Anaerobic Digestion

•  Process cake from PK and NR to Class A at YJ

•  Covers all seven WRRFs •  $30-$45 million

25-Year Plan – Mass Balance

25-Year Plan – Source of Savings Over $5 million/yr extra savings with 25-Year Plan Improvements

Conclusions

•  5-Year Plan sets up 25-Year Plan

•  25-Year Plan has multiple options with potential to save $100/DT depending on truck traffic/capital/ammonia loading. Class A is KEY. TPAD economics based on reusing YJ digesters.

•  Total $45-$67 million

Wet tons

Thank you for your attention

Acknowledgements

•  Westchester County, NY: •  Department of Public Works and Transportation (DPWT)

•  Department of Environmental Facilities (DEF)

•  Our project partners: