Biosolids Drying SystemsCan they be part of an energy efficient project?

Agenda

Biosolids: The Problem

Biosolids Dryers

Case Studies

Proposed Approach

Biosolids: The Problem

What are Biosolids?

Biosolids Processing Optionso Thickeningo Dewatering o Drying

Treatment Technology: ThickeningGravity Thickening Flotation Thickening Mechanical Thickening

Advantages

• Lowest capital, energy, and O&M costs

• Simple to design, operate and maintain

• Good performance • Highest performance (4% to 6%)

• Require small to moderate size for working area

• Simple to design and operate

Disadvantages

• Lowerperformance

• Require larger footprint

• Aesthetic and odor concerns

• Highest capital, energy, and O&M costs

• Significant operator attention to operate and maintain

• Require larger footprint

• Medium capital, energy, and O&M costs

• Two waste streams (filtrate and belt washwater)

Treatment Technology: DewateringNatural Dewatering Mechanical Dewatering

Advantages

• Simple to design and operate• Requires less energy • Lower operational and chemical

costs

• High performance (20% - 35%)• Adaptable to varying influent solids

conditions• Moderate disposal and hauling costs• Requires small land area• Low capital costs

Disadvantages

• High capital costs• Effectiveness depends on climatic

conditions• Require periodic excavation and

removal of dewatered sludge -> expensive

• Require large land area

• Medium to high energy and chemical costs

• Requires moderate to significant operator attention

• Two waste streams (filtrate and belt washwater)

Treatment Technology: DryingOpen-Air Drying Mechanical Drying

Advantages

• Simple to design and operate• Requires minimal energy input• Lower O&M and chemical costs

• Achieve up to 97% solids• Low disposal and hauling costs• Requires low to moderate land area

Disadvantages

• Effectiveness depends on climaticconditions

• May require years to achieve the desired solids content

• Require large land area• Lower solids content output

• Higher energy, thermal, and chemical costs

• High capital costs• Two waste streams (filtrate and belt

washwater)

Biosolids Dryers

Graphic courtesy of Gryphon Environmental, LLC.

Operating Principle

Graphic courtesy of ELIQUO STULZ

Benefits

Disposal Methods• Burial in a Landfill • Beneficial Reuse

Regulatory Requirements/Guidelines

• Design residuals treatment processes:o 10 States Standardo AWWA Water Treatment Plant Design

• Disposal:o 1972 Clean Water Act (NPDES/USEPA) –

Regulation of Discharges to Natural Waterways, Regulation of Discharge into Sewer Systems

o Subtitle D of the Resource Conservation and Recovery Act (USEPA) – Regulation of Permanent Lagoons and Landfills

o 40 CFR 503 and 40 CFR 507 (ASCE/AWWA/EPA) – Regulation of Land Application

Type of Sludge Quality & Quantity

Disposal Types Available

Regulatory Restrictions

Sludge Quantity Reduction

Treatment Processes

Design Selection

Evaluation Approach

Desktop Analysis

Biosolids & Drying• Biosolids composition• Biosolids conveyance, storage and end

user loading• Alternate means of disposal during dryer

outages• Reduce costs and provide flexibility in

operation• Daily operations• Final equipment sizing and costs• Fuel source gas cleaning, blending,

compression, safety, and distribution.

Case Study:

Onondaga Water Environmental Protection (WEP)

Sludge Disposal Cost $3.4M Annually

Sludge Dryer Cost $14.5M (installed)

Dryer Fuel & Power Cost $500,000

Sludge Disposal Savings -$2.1M

Simple Payback 9.1 years

Diesel FuelEnergy Savings

23,700 Wet Tons Sludge Hauled Reduction

99 Miles of Hauling

234,000 Gallons Diesel Fuel

32,300 mmBTU in Energy Savings

Landscape Spreading Energy Savings

39,000 Wet Tons 15,000 Wet Tonnage

180 BTU/LB 16 BTU/LB due to Increased % Solids

14,000 mmBTU 500 mmBTU

13,500 mmBTU in Energy Savings

Case Study:

Village of Endicott Wastewater Treatment Plant

Project Driverso Address Failing

Infrastructureo Address Inefficient

Processo Do What Is “Right”

What makes a successful project?o Maintain Class A

Biosolidso Eliminate Existing

Compost Operation (Energy and Labor Costs)

o Enhanced Septage Receiving

What Are My Options?

o Do Nothingo Modify the

Existing Process (Can We Make it More Efficient?)

o Change the Process

Dryer Design Criteria o Utilize Excess Digester

Gas at Dryero “Future Max Month”

Solids Loading conditions within approximately 40 hours of operation per week

o Disposal to farmers with potential winter storage under existing canopy structure

Sludge Dryer Cost $3.0M (installed)Dryer Fuel & Power Cost -$14,250

Project Savings -$0.3M

Simple Payback 9.5 years

Proposed Approach for Sludge Drying

ICE: INTEGRATED CAPITAL & ENERGY IMPROVEMENTS

exploring the seen

and unseen.

ICE Approach Planning Phase Design Project

Improvements Implementation Results

ICE Benefits • Save Money, Reduce

Energy, Operational, & Maintenance Costs• Increase Revenue• Integrate Energy Efficiency

into Capital Improvement Programs• Additionally - Meet More

Stringent Regulations

Onondaga County WWTP• A comprehensive ICE evaluation

was performed on the six WWTPs making up the County System

• Over $24.5 million of integrated energy and capital improvements

• Over 6.3 million KWHrs of electrical savings and $2.1M of savings annually

• $2.3 million in energy incentives

• 11.6 year payback

Questions

Washington CountyEnergy Performance Contract

City of North Tonawanda Wastewater Treatment PlantBiosolids Dryer Analysis

Endicott Wastewater Treatment Plant UpgradesEngineering Design & Construction Services

Onondaga CountyEnergy Study & Energy Performance Contract

Town of AmherstBiosolids Dryer Analysis

Village of GowandaBiosolids Dryer Evaluation

Erie County Water AuthorityBiosolids Dryer Evaluation

Private Industrial ClientDryer Procurement & Design

Drinking Water Sludge

EPC for Biosolids Drying

Currently in Construction

Increased Revenues &

Biosolids Drying

THANK YOU