lca waste dizertatii

8/8/2019 LCA Waste Dizertatii

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Life Cycle Environmental Aspects ofLife Cycle Environmental Aspects of

Landfills and WasteLandfills and Waste--toto--Energy SystemsEnergy SystemsMeeting of the Committee on Geological and

Geotechnical Engineering

Board on Earth Sciences and Resources,National Research Council

February 1, 2007

Keith WeitzRTI International


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ObjectivesObjectives

Background on life cycle concept

Landfill discussion

Waste-to-energy discussion

Summary of life cycle tradeoffs


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What is Life Cycle Assessment?What is Life Cycle Assessment?

A systems analysis, not

isolated operations.

Considers upstream anddownstream burdens.

Multi-media and multi-pollutant.

Main components:

Goals and Scoping

Inventory Analysis

Impact Assessment

Interpretation


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Life Cycle for Solid Waste ManagementLife Cycle for Solid Waste Management

Collection RecyclingandComposting

WTE

MaterialsRecycling

AshLandfill

MSWLandfill

CompostProduct

Use


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Life Cycle Inventory ModuleLife Cycle Inventory Module

Waste Management

Activity/Operation

Energy Materials

Solid

Waste

AirEmissions

Products

Energy

Water

Pollution ResidualWaste


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LandfillsLandfills


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Old Landfill DesignOld Landfill Design Managed DumpsManaged Dumps


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Modern Landfill DesignModern Landfill Design HighlyHighly

Engineered SitesEngineered Sites


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US Federal MSW Landfill StandardsUS Federal MSW Landfill Standards

Location restrictions.

Composite liners requirements.

Leachate collection and removal system requirements.

Operating practices.

Groundwater monitoring requirementsrequires testing.

Closure and postclosure care requirements.

Corrective action provisions for control and clean up landfill

releases to achieve groundwater protection standards. Financial assurance for environmental protection during

closure and post-closure care.


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LandfillLandfill LeachateLeachate Collection andCollection andTreatment: Offsite or OnsiteTreatment: Offsite or Onsite

Leachate Collection System

Offsite

Treat

ment

OnsiteTreatment


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Landfill Gas Collection andLandfill Gas Collection and

Management:Management: FlareFlare or Energy Recoveryor Energy Recovery

Landfill Gas Collection System

Flare

EnergyRecovery


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WasteWaste--toto--EnergyEnergy


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WasteWaste--toto--EnergyEnergy SystemsSystems

Thermal Systems:

Mass Burn

Controlled-Air, Modular-Municipal

Gasification

Pyrolysis

Non-Thermal Systems: Anaerobic digestion

Hydrolysis


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Mass Burn TechnologyMass Burn Technology

Well proven technology for MSW.

Minimum waste preparation.

Higher capital cost.

Complete burnout residues.

Reduce waste volume by 75-80%.

Metals can be recovered. Ash can be reused or landfilled.


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Mass Burn WTE Plant: Water and AirMass Burn WTE Plant: Water and AirPollution Control SystemsPollution Control Systems

Waste

water

Baghouse

Modern Mass Burn WTE Plant


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Life Cycle Comparison of LandfillLife Cycle Comparison of Landfilland WTE Optionsand WTE Options


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Net Total Cost for WTE and LandfillNet Total Cost for WTE and LandfillOptionsOptions

Per 1,800,000 tons of waste and assuming equal 20 mile haul distance.

0

50,000,000

100,000,000

150,000,000

200,000,000

250,000,000

Landfill - Vent Landfill - Flare Landfill - Energy WTE

Annual

Cost($)


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Net Total Energy Consumption forNet Total Energy Consumption forWTE and Landfill OptionsWTE and Landfill Options


-30,000,000

-25,000,000

-20,000,000

-15,000,000

-10,000,000

-5,000,000

0

5,000,000


A

nnualEnergyConsumption(MBTU


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Net Total Life Cycle Carbon EmissionsNet Total Life Cycle Carbon Emissionsfor WTE and Landfill Optionsfor WTE and Landfill Options


-200,000

-100,000

0

100,000

200,000

300,000

400,000

500,000

Landfill - Vent Landfill - Flare Landfill - Energy WTEAnnualCarbonEm

issions(MTCE


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Net Total Life Cycle Criteria EmissionsNet Total Life Cycle Criteria Emissionsfor WTE and Landfill Optionsfor WTE and Landfill Options


-10,000,000

-9,000,000

-8,000,000

-7,000,000

-6,000,000

-5,000,000

-4,000,000

-3,000,000-2,000,000

-1,000,000

0

1,000,000

2,000,000

3,000,000

4,000,000

5,000,000


Pound

sPM

SOxNOx

CO


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Summary of Life Cycle TradeoffsSummary of Life Cycle Tradeoffs

Both are well established and tested, accept

unprocessed waste, have pollution controlrequirements.

Landfill typically cheaper

WTE more efficient at recovering energy

WTE avoids landfill methane

WTE can include metals recovery

WTE produces ash that must be managed


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Thank YouThank You

Keith A. Weitz

RTI International

3040 Cornwallis RoadRTP, NC 27709

Ph: 919-541-6973

Fax: 919-541-7155

Email: [email protected]

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