Docstoc

Communications NREL PowerPoint Presentation Template with Dark ... - PowerPoint

Document Sample
Communications NREL PowerPoint Presentation Template with Dark ... - PowerPoint Powered By Docstoc
					                             Climate Technology Partnership Workshop
                         jointly organized by KEMCO, U.S. EPA and NREL

                                      14-15 June 2004, Seoul, Korea



          Gas Generation and Recovery
         Model Developed for Thailand and
          Feasibility Study for Cheong ju

                       Presented by David L. Howard
                 Based largely on presentations developed by
             Brian Guzzone of U.S.EPA LMOP and Alex Stege of
                               SCS Engineers
Korea Energy Management Corporation
                     Presentation Outline
          • Factors affecting a site’s potential for landfill
            gas utilization
          • Using the factors to perform feasibility study
            at Cheong ju landfills
          • Using the factors to analyze potential of
            landfills for a country - Thailand
          • Possible follow on steps after completing
            initial analysis with the models


Korea Energy Management Corporation
        Potential Landfill Gas Project Sites
   • Factors affecting a site’s
     potential for landfill gas
     utilization
       – Site location
       – Waste quantity and
         composition
       – Waste disposal rates: past
         and future
       – Climate and moisture
       – Other considerations



Korea Energy Management Corporation
                   Disposal Site Location
   – Landfill serves
     population which
     generates significant
     quantities of waste
   – Landfill open or is
     recently closed
   – Facility with power
     needs located near
     landfill
   – Landfill located near
     power grid


Korea Energy Management Corporation
                               Site Location
   • Site acceptance
        – Landfill gas utilization
          project is to be
          accepted by the local
          government and
          community
        – Demonstrates
          commitment to
          improving local
          environment

Korea Energy Management Corporation
                    Waste Disposal Rates
   • Waste quantity
       – >0.3 million metric tons of
         waste in place and >0.5
         million metric tons capacity
   • Waste composition
       – Higher organic waste % =
         higher methane production
   • Waste age
       – Older waste produces less
         methane




Korea Energy Management Corporation
                            Site Conditions
  • Status of Landfill Operation
       – Open or recently closed
  • Landfill Type
       – Managed Landfills
            • daily cover, compaction
            • leachate management
            • liner
       – Dump Sites Present challenges
            • Poor design and management
            • Fires
            • Scavengers
  • Landfill Depth
       – Greater than 5 m preferred
       – Greater than 10 meters is optimal
Korea Energy Management Corporation
           Climate and Moisture Levels
  • Climate
       – High rainfall at sites
         contributes to rapid waste
         decay
       – Sites with low rainfall have
         slower waste decay
  • Management of Moisture
    in the Landfill
       – Leachate management
       – Landfill stability




Korea Energy Management Corporation
                    Other Considerations
• Geology/ Hydrogeology
     – Presence of liner and/or clay
       soils beneath site
• Temperature
     – Methane production is
       maximized between 35-57
       degrees Celsius
• Other factors:
     – Landfill design
     – Site-specific factors




Korea Energy Management Corporation
         Utilization Options for Landfill
                       Gas
  • Are there uses for the
    energy recovered?
  • Direct use
  • Electricity generation
  • Gas processing
  • Emerging technologies




Korea Energy Management Corporation
            Are There Uses For The Energy
                     Recovered?

    • Ask yourself these questions, are there….
    1) Residential areas that could use a supplemental source of
       fuel?
    2) District heating plants that can use medium quality gas?
    3) Industrial facilities nearby that can use medium quality gas?
    4) Medium-quality gas distribution networks?



Korea Energy Management Corporation
            Are There Uses For The Energy
                     Recovered?
    • Additionally...
    5) Are high-quality gaseous fuels very costly, making gas
       processing potentially cost effective?
    6) Are there electric power distribution systems that do (or
       can) obtain power from project such as landfills?
    7) Would you consider gas recovery as a lost-cost alternative
       approach for reducing methane emissions even if it is not
       profitable in its own right?


Korea Energy Management Corporation
          Identify Other Favorable Options
     • Find Supportive
       Project Partners
         – Regulatory agencies
         – Utility companies
         – Governmental agencies
         – Private industry
         – Adjacent land owners
           and residents
         – Multi-lateral banks
         – Financial institutions


Korea Energy Management Corporation
                          Cheong ju Landfill

        • In 2002, SCS Engineers, a U.S. EPA
          contractor conducted a feasibility
          analysis of the two Cheong ju landfills
        • Purpose of the study was to determine
          options for developing LFG projects at
          the sites



Korea Energy Management Corporation
              Criteria Used for the Analysis
      •   Reviewing Solid Waste Management Practices
      •   Reviewing Site Information
      •   Preparing a Landfill Gas Recovery Estimate
      •   Preparing a Landfill Gas System Concept
      •   Evaluating Energy Utilization Options
      •   Reviewing the Institutional Framework
      •   Reviewing Emission Reduction Credit Criteria
      •   Performing an Environmental Effects Assessment
      •   Performing an Economic Evaluation
Korea Energy Management Corporation
               Model Used to Estimate Gas
                      Production
                              • Q = Lo R (e-kc - e-kt)
    • Where:
        –   Q = Methane generated in current year (m3/yr)
        –   Lo= Methane generation potential (m3/Mg of refuse)
        –   R = Average annual waste acceptance rate (Mg/yr)
        –   k = Methane generation rate constant (1/yr)
        –   c = Time since/to landfill closure (yr)
        –   t = Time since landfill opened (yr)


Korea Energy Management Corporation
                         Economic Analysis

        • Once the gas production is estimated
            – Collection system is modeled
            – Utilization options analyzed
            – Potential for generation of carbon credits
              assessed
            – Economic analysis included
                 • Cash flow analysis
                 • Net Present Value analysis



Korea Energy Management Corporation
                         Economic Analysis
                             continued
        • Evaluation of economic results strategy
            – Minimising the initial capital investment that is
              necessary to implement the initial LFG recovery
              system.
            – Maximising LFG recovery rates (within the
              limitations of the above item) by focusing on
              selected portions of the disposal area.
            – Maximising the value of the Emission Reduction
              Credits.


Korea Energy Management Corporation
     Application to a Nationwide Analysis

      • At about the time the Cheong ju feasibility
        study was complete, EPA with the World
        Bank analyzed landfill gas potential in
        Thailand.
      • The evaluation used many of the same
        tools to provide a country wide data base
        of the economic potential of landfills


Korea Energy Management Corporation
                               Approach
      • Thailand landfill gas model based on
        USEPA’s LandGEM
      • Thailand landfill gas model outputs:
           – Estimates landfill gas generation rates
           – Estimates landfill gas recovery potential
      • Evaluation of suitability of site
        conditions based on responses to
        World Bank disposal practices
        survey.
Korea Energy Management Corporation
            USEPA’s Thailand Landfill Gas
                      Model
          • Model inputs - site specific information:
               – Historic and projected waste disposal rates
               – Average annual rainfall

          • Model inputs - regional information:
               – Thailand waste composition
          • Model equation estimates annual landfill gas
            generation
          • Model estimates annual landfill gas recovery


Korea Energy Management Corporation
                         Key Model Inputs
      • Annual waste
        disposal rates
      • Methane decay
        rate (“k”)
      • Methane
        generation
        potential (“Lo”)
      • Collection
        efficiency
Korea Energy Management Corporation
             Model Inputs – Disposal Rates
        • Mass of waste disposed each year
             – Historical disposal data estimated using
               data obtained from World Bank
             – landfill practices survey of municipalities
             – Estimated future disposal rates account for
               site capacities
             – Possible regional or provincial disposal
               sites scenario


Korea Energy Management Corporation
          Model Inputs – Rate Constant (k)
         • “k” – refuse decay rate constant
           (units = 1/year)
              – Sets rate of waste decay and methane
                production
              – Influenced by waste moisture – use annual
                rainfall
              – High rainfall at Thailand sites (900 – 5000
                mm per year) create very high k values
              – High k values confirmed by Chiang Mai
                University study
Korea Energy Management Corporation
                   Model Inputs – Methane
                   Generation Potential (Lo)
         • “L0” – methane generation potential
           (units = m3 methane per metric tonne
           [Mg] of waste)
             – Total amount of methane one tonne of
               waste produces
             – Thailand Lo estimate based on Bangkok
               waste composition



Korea Energy Management Corporation
                  Model Inputs – Collection
                         Efficiency
           • Collection efficiency =
                     Amount of landfill gas collected
                     Amount of landfill gas generated
           • Collection efficiency based on:
                – Type of facility (landfill vs. dump)
                – Type/design of collection system
                – Extent collection system covers waste volume
                – Waste characteristics – permeability
                – Collection system operation
Korea Energy Management Corporation
                  Methodology – Model
                       Equation
            • Landfill gas generation equation:
            Landfill gas generation = 2 k L0 M e-kt
            where:
                k = refuse decay rate (1/yr)
                L0 = methane generation potential (m3/Mg)
                M = mass of waste deposited per year (Mg)
                t = age of waste (years)
            Note: This derivative of earlier model shows generation
            in one year.
Korea Energy Management Corporation
                             Methane
                         Rate Constant (k)
          • Range of observed values:
               – 0.01 1/year (desert landfills) to 0.45 1/year
                 (“bioreactors”)
          • Estimated range of k values for Thailand
            disposal sites:
               – 0.065 to 0.15 (1/yr)
          • Estimated k value for Cheong ju site
               – 0.085 (1/yr) based on rainfall analysis



Korea Energy Management Corporation
                        Methane
                Generation Potential (Lo)
        • Range of observed values:
            • 0 - 312 m3 methane/Mg of waste
        • Estimated Lo value for Thailand disposal
          sites:
            – 78 m3CH4/Mg
            – Based on average organic and solids content
        • Estimated Lo value for Cheong ju
            – 39 m3CH4/Mg
            – Based on average organic and solids content

Korea Energy Management Corporation
             Projected LFG Recovery
                       Rate
        • Landfill gas recovery = landfill gas
          generation x collection efficiency
        • Collection efficiency Thailand sites:
            – Engineered and sanitary landfills: 60%
            – Open and controlled dump sites: 50%

        • Collection efficiency Cheong ju
            – Based on planned system: 75%

Korea Energy Management Corporation
        Evaluation of Suitability of Landfill
                 Site Conditions
    • World Bank survey of sites-Thailand
         – Management practices
              • Daily cover , compaction of waste
              • Presence of clay or plastic liner
              • Presence of leachate drainage system
         – Environmental conditions
              • Leachate adequately contained
              • No fires
              • No scavengers living on landfill
         – Depth of waste: > 5 m

Korea Energy Management Corporation
                     Modeled Thailand Sites
    Central Region:
    • 11 landfills, 5 dump
      sites
    • Sites with largest landfill
      gas potential currently:
         –   Bangkok-Kampangsean
         –   Bangkok-Ratchathewa
         –   Nonthanburi
         –   Pathum Thani                San

    • Sites with largest future          Suk

      landfill gas potential:
         – Bangkok-Kampangsean
         – Bangkok-Ratchathewa

Korea Energy Management Corporation
                                Sample Model Output – Bangkok-
                                    Kampangsaen Landfill
                                                             Landfill Gas Generation and Recovery
                                                               Bangkok- Kampangsaen Landfill

                                          20,000                                                                  30
        Gas Flow at 50% Methane (m3/hr)




                                                                                                                       Project Generation Potential (MW)
                                                                                                                  25
                                          15,000
                                                                                                                  20


                                          10,000                                                                  15

                                                                                                                  10
                                           5,000
                                                                                                                  5

                                              0                                                                   0
                                               1990   1995     2000    2005   2010    2015    2020      2025   2030

                                                      Generation, k=0.08             Recovery, k=0.08
                                                      Generation, k=0.15             Recovery, k=0.15

Korea Energy Management Corporation
                       Sample Model Output – Megalo
                                                       Exhibit 4-1
                                Landfill Gas Generation and Recovery Projection (Flow)
                                         Megalo Landfill, Cheongju, South Korea

                      1,200




                       900


                                                                                                Generated
        LFG (m3/hr)




                       600                                                                      Recovered
                                                                                                Passive


                       300




                         0
                         2001    2006    2011    2016   2021    2026    2031   2036      2041
                                                        Year




Korea Energy Management Corporation
                      Overview of Results
                           Thailand
                                     Existing Sites:
         Size of Potential Landfill Gas Facilities   Suitability of Landfill Conditions for
                                                                LFG Developm ent
                                                                             not
              0.5-1 MW
                             4-10 MW                     low            assessed
               2 sites
                              2 sites                   5 sites            3 sites

        0.2-0.5
                                                                                    high
          MW
                                                                                   24 sites
        13 sites
                                                        medium
                                        <0.2 MW         24 sites
                                        39 sites



              Potential Regional or Provincial Sites:
             2 landfills can accommodate regional waste (1-8 MW)
             8 landfills can accommodate provincial waste (0.2-7 MW)
Korea Energy Management Corporation
                                  Existing Sites
                          Potential Projects at Large Disposal Sites*
                                           Project          Project           Landfill
             Site Name                     Capacity         Duration         Suitability
                                            (MW)            (Years)         for Project

             Bangkok-Kampangsean                 10        15 (2004-2018)    medium
             Bangkok- Ratchathewa                4         16 (2004-2019)     high
                                                0.5        23 (2004-2026)     low
             Nonthaburi
                                                0.7        10 (2013-2022)
             Nakorn Ratchasima                  0.5        12 (2004-2015)     high
             Nakorn Pathom                      0.4        23 (2004-2026)     high
             Pathum Thani                       0.4        10 (2004-2013)     high
             Hat Yai                            0.4        16 (2004-2019)       -
                                                0.2        35 (2004-2038)    medium
             Phitsanulok
                                                0.5        14 (2013-2026)
                                                0.2        42 (2004-2045)       low
             Kampang Phet
                                                0.3        31 (2012-2042)
             Songkhla                           0.2        50 (2004-2053)      high
             *Includes sites with capacities > 1,000,000 tons

Korea Energy Management Corporation
                        Potential Regional Sites

                           Potential Projects at Potential Regional Sites*
                                               Project            Project           Landfill
              Site Name                        Capacity           Duration         Suitability
                                                (MW)              (Years)         for Project
                                                  2-5          20 (2008-2013)            high
              Chiang Mai                          5-8          14 (2014-2027)
                                                  2-5          14 (2028-2041)
                                                  1-2          14 (2008-2012)            low
              Ubon Ratchathani                    2-3          11 (2013-2023)
                                                  1-2          14 (2024-2032)
              *Assumes disposal site will receive all waste from the home province and
              neighboring provinces.




Korea Energy Management Corporation
           Confidence Levels for Model
                    Results
     • Sources of Uncertainty:
          –   Methodology – model accuracy
          –   Data quality
          –   Collection efficiency
          –   Other factors
     • Estimates in the range of +/- 30 %
     • Model accuracy improved by field studies



Korea Energy Management Corporation
                   Options for follow up:
                   Field Testing Program
   • Field testing at
     potential
     project sites
        • Install test wells
        • Perform testing
          and monitoring
        • Field Testing
          Issues
        • Confidence
          Levels

Korea Energy Management Corporation
                          Install Test Wells




         • Install vertical extraction wells or horizontal
           collectors in the landfill
         • Flare recovered gas to control discharge
Korea Energy Management Corporation
                           Perform Testing
                           and Monitoring
   • Balance the well
     field
   • Recover gas
     continuously
     during testing
     period

    Monitor gas quantity and quality at the
     flare station and at each well
    Review test results
Korea Energy Management Corporation
                      Field Testing Issues
• Advantages:
     – Provides site-specific data
     – Provides information on
       landfill leachate levels
• Disadvantages:
     – Cost increase
     – Potential inaccuracies
     – Limited information on
       seasonal variations

Korea Energy Management Corporation
             Confidence Levels for Field
                  Testing Program
     • Sources of inaccuracy:
          – Estimating total landfill gas flow from field test
               • Landfill gas from only portion of site during field test
               • Need estimated waste volume under influence of
                 test wells
          – Recovery during test may not be sustainable
            over long term
     • Can extend testing program to improve
       accuracy
Korea Energy Management Corporation
                    Options for follow up:
                      Feasibility Study

      • Recommend feasibility studies for potential
        project sites
           – Refine landfill gas recovery projections by calibrating
             model to results of field test
           – Project developer likely to require feasibility study
           – Feasibility study can include evaluation of project
             financial information



Korea Energy Management Corporation
                                      Summary
     • Information on landfill gas recovery rates
       critical for finding suitable project sites and
       sizing equipment
     • Analysis can be done for single sites or all
       sites in the country
     • Follow-up studies at potential project sites
       may be warranted
          – Field testing
          – Feasibility studies



Korea Energy Management Corporation

				
DOCUMENT INFO