9943871 unfccgreen-house-training


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  • National communications preparation is an evolving process. New UNFCCC guidelines and GPG2000 have created new possibilities to surpass difficulties and limitations that have been flagged. UNFCCC’s User Manual for the Guidelines on National Communications from Non‑Annex I Parties is a new tool that needs to be considered. COP = Conference of the Parties IPCC = Intergovernmental Panel on Climate Change NAI = non-Annex I Party (Party not included in Annex I to the Convention) UNFCCC = United Nations Framework Convention on Climate Change GHG = greenhouse gas(es).
  • This handbook is a tool to overcome the complexities of a sector like Waste, that has both biological processes as a simple chemical process (namely incineration). EFDB = IPCC emission factor database AD = activity data EF = emission factor
  • Waste sector is relevant in countries with large urban populations, particularly in countries with cities that have more than one million inhabitants (that is the case for all the above mentioned countries). As the main source is generally methane (CH 4 ) emissions from solid waste disposal sites, this gas is the most relevant. In countries with low agricultural and industrial emissions, the waste sector may also become a significant source of nitrous oxide (N 2 O). Analysis of national communications has shown that methane emissions from solid waste disposal sites is commonly a key source
  • There are two types of processes associated with waste management: Rotting Burning In the first case, the emissions come from (anaerobic) decomposition occurring slowly and liberating carbonaceous and nitrogenous substances. In the second case, emissions include carbon dioxide, due to the oxidation processes involved.
  • The decomposition of waste is a biochemical process triggered by micro-organisms. In this slide, the processes (source, process and emissions) that lead to the different emissions are pointed out.
  • Characteristics of this category are presented here: Type of activity Characteristics of the process Emissions produced Accounting issues
  • In this slide, additional details of the decomposition process are presented in order to help explain the basic biochemistry of the process. This is relevant for the correct interpretation of the influence of physical factors in the process.
  • Practices that are not fully represented in the IPCC 1996GL or the GPG2000 are presented in this slide. These practices are common in NAI countries and are here to raise the debate on the approaches used to deal with them.
  • In this slide, the characteristics of proper landfills are presented. This slide is here to remind that in many NAI countries these conditions are not fully achieved.
  • This slide stresses the importance of waste composition as a factor in methane production.
  • In this slide, the stress is on the importance of physical factors, essentially moisture and temperature. The slide is a reminder of the influence of weather on methane production.
  • In this slide, the uncertainty related to chemical conditions is presented as an important factor limiting accuracy.
  • In this slide, an idea of the importance of the source category is presented. Also, the importance of the industrial waste-water subcategory is stressed.
  • In this slide, the particular characteristics of methane emissions from waste water are presented. Note that they are different than those for solid waste.
  • The concept of biochemical oxygen demand is essential for understanding the decomposition processes in water.
  • Particularities concerning waste incineration are raised: Combustion of biomass-based matter not to be accounted Nitrous oxide a product of incineration of protein-rich organic matter (sludge)
  • From IPCC 1996GL.
  • This and the next slide present an algorithm that is valid for any sector, and it is here for the sake of completeness.
  • Calculation methods proposed for this source category in IPCC 1996GL.
  • This simple method, used in several cases by NAI countries, gives good approximate results if decomposition conditions are optimal.
  • This is the simplest method.
  • This calculation method requires more knowledge about the waste stream composition, but this is easily obtainable.
  • This equation presents all the factors relevant to calculate the emissions of methane using the simple method.
  • Notice the relationship between the amount of DOC dissimilated fraction and temperature, indicating the influence of one physical factor on the process.
  • This slide lists the major caveats that restrict the wider application of this simple method.
  • This slide and the following four slides present the improvements introduced to this calculation by GPG2000, leading to the Tier 1 or Default Method.
  • This slide presents some approaches that may be used when activity data indicate different conditions.
  • Here, the main differences between Tier 1 and Tier 2 are highlighted.
  • In this base equation, the time relationship is evident – variables “c” and “t”.
  • The good practice equation introduced here gives a clear idea of the dynamics and additional to the calculation process.
  • This slide lists the required factors.
  • The methane generation rate constant is the keystone of Tier 2. A good understanding of this factor is vital for the proper application of Tier 2. Proper calculation of “k” is essential.
  • The slide presents the factors upon which “k” depends. Through careful evaluation of national circumstances, values can be generated to replace the default values.
  • This slide repeats the previously stated concept of methane generation potential, and it is here in the interest of completeness.
  • The slide presents additional factors that determine REAL emissions. Recovery and oxidation and the order in which to deal with them are included here.
  • The countries that have used this equation.
  • Another possible but uncommon calculation route is briefly introduced here.
  • Key uncertainties relating to SWDS emissions.
  • The basic assumptions relating to methane and nitrous oxide emissions from waste-water treatment.
  • The slide presents the use of a simplified approach for domestic and commercial waste water. This method is efficient for most countries.
  • GPG2000 includes a simple calculation for methane from waste water. It is called the “check method” and its factors, including its default values, are presented in this slide.
  • For the basis of this method, see the factors presented on slide 25.
  • A comparison of BOD and COD is presented here. This is important with respect to the prevailing measurement practices. Methane conversion factor (explained on the next slide) is introduced.
  • First, the approach of IPCC 1996GL is challenged by the first two statements. The use of expert knowledge is stressed by the last statement.
  • Some important characteristics of industrial waste waters are stressed: On site calculations ONLY Keep the focus on KEY industries
  • The equation version of the algorithm from the previous slide is presented here.
  • Notice the similarities with slides 67 and 68.
  • This slide presents the equation derived from the previous slide.
  • Key uncertainties for waste-water treatment emissions are presented here.
  • In this slide, the main characteristics of waste incineration accounting are presented.
  • The equation for carbon dioxide stresses the need to differentiate the four types of waste: municipal, hazardous, clinical and sludge.
  • In this slide presente two equations for calculting nitrous oxide emissions, depending on the data available: First equation uses emission factor Second equation uses nitrous oxide emission concentration in flue gas
  • This slide presents the major assumptions used in calculating carbon dioxide emissions from waste incineration.
  • The particularities of nitrous oxide calculation are stressed. The calculation must take into account the composition of waste and the incineration process.
  • Here, the most common general reporting recommendations are presented.
  • Here, the most common QA/QC reporting recommendations are presented.
  • Notice the importance of “k” value (methane generation rate constant), waste composition and comprehensiveness of the assessment.
  • In this slide, major issues to do with reporting on this source category are stressed: Separation between flaring and recovery, documentation of parameter changes and time series consistency.
  • Some key details on reporting are presented here for review. COD = chemical oxygen demand.
  • Some key details on reporting are presented here as reminders.
  • Parties are recommended to review the above-mentioned section of the Guidelines to check if the method is applicable according to national circumstances.
  • The issues related to EF default values and the relationship between the source category and the Energy sector are highlighted here.
  • In several cases GPG 2000 provides a better and simpler calculation tool than does IPCC 1996GL.
  • This slide is just meant to draw attention to the fact that no new tables were introduced in GPG2000..
  • This slide, introduces the problems found, categorizes them and proposes approaches to deal with them.
  • Lack of coverage of issues relevant to NAI countries is presented here.
  • Some suggestions to lacks or gaps identified are proposed.
  • Some suggestions to fix deficiencies.
  • Some methodological issues not properly covered by the Table 6.A .
  • Common problems related to AD and EF for NAI countries.
  • This slide presents an approach for dealing with AD scarcity.
  • BOD = biochemical oxygen demand
  • 9943871 unfccgreen-house-training

    1. 1. CGE Greenhouse Gas Inventory Hands-on Training Workshop WASTE SECTOR
    2. 2. Overview <ul><li>Introduction </li></ul><ul><li>IPCC 1996GL ( Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories ) and GPG2000 ( Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories ) </li></ul><ul><li>Reporting framework </li></ul><ul><li>Key source category analysis and decision trees </li></ul><ul><li>Tier structure, selection and criteria </li></ul><ul><li>Review of problems </li></ul><ul><ul><li>Methodological issues </li></ul></ul><ul><ul><li>Activity data </li></ul></ul><ul><ul><li>Emission factors </li></ul></ul><ul><li>IPCC 1996GL category-wise assessment and GPG2000 options </li></ul><ul><li>Examination and assessment of activity data and emission factors: data status and options </li></ul><ul><li>Uncertainty estimation and reduction </li></ul>
    3. 3. Introduction
    4. 4. Introduction <ul><li>COP2 adopted guidelines for preparation of initial national communications (decision 10/CP.2) </li></ul><ul><li>IPCC guidelines used by 106 NAI Parties to prepare national communications </li></ul><ul><li>New UNFCCC guidelines adopted at COP8 (decision 17/CP.8) provided improved guidelines for preparing GHG inventory </li></ul><ul><li>UNFCCC User Manual for guidelines on national communications to assist NAI Parties in using latest UNFCCC guidelines </li></ul><ul><li>Review and synthesis reports of NAI inventories highlighted several difficulties and limitations of using IPCC 1996GL (FCCC/SBSTA/2003/INF.10) </li></ul><ul><li>GPG2000 addressed some of the limitations and provided guidelines in order to reduce uncertainties </li></ul>
    5. 5. Purpose of this Handbook <ul><li>GHG inventories are mostly biological sectors, such as Waste, and characterized by: </li></ul><ul><ul><li>methodological limitations </li></ul></ul><ul><ul><li>lack of data or low reliability of existing data </li></ul></ul><ul><ul><li>high uncertainty </li></ul></ul><ul><li>This handbook aims at assisting NAI Parties in preparing GHG inventories using the IPCC 1996GL, particularly in the context of UNFCCC decision 17/CP.8, focusing on: </li></ul><ul><ul><li>the need to shift to GPG2000 and higher tiers/methods to reduce uncertainty </li></ul></ul><ul><ul><li>complete overview of the tools and methods </li></ul></ul><ul><ul><li>use of IPCC inventory software and EFDB </li></ul></ul><ul><ul><li>review of AD and EF and options to reduce uncertainty </li></ul></ul><ul><ul><li>use of key sources, methodologies and decision trees </li></ul></ul>
    6. 6. Target groups <ul><li>NAI inventory experts </li></ul><ul><li>National GHG inventory focal points </li></ul>
    7. 7. NAI country examples <ul><li>Review of national communications: Argentina, Colombia, Chile , Cuba and Panama </li></ul><ul><li>GHG inventories show that the Waste sector may be significant in NAI countries </li></ul><ul><li>Commonly a significant source of CH 4 </li></ul><ul><li>In some cases a significant source of N 2 O </li></ul><ul><li>Solid waste disposal sites (SWDS) frequently a key source of CH 4 emissions </li></ul>
    8. 8. Definitions <ul><li>Waste emissions – Includes GHG emissions resulting from waste management activities (solid and liquid waste management, excepting CO 2 from organic matter incinerated and/or used for energy purposes). </li></ul><ul><li>Source – Any process or activity that releases a GHG (such as CO 2 , N 2 O, CH 4 ) into the atmosphere. </li></ul>
    9. 9. Definitions (2) <ul><li>Activity Data – Data on the magnitude of human activity, resulting in emissions during a given period of time (e.g. data on waste quantity, management systems and incinerated waste). </li></ul><ul><li>Emission Factor – A coefficient that relates activity data to the amount of chemical compound that is the source of later emissions. Emission factors are often based on a sample of measurement data, averaged to develop a representative rate of emission for a given activity level under a given set of operating conditions. </li></ul>
    10. 10. IPCC 1996GL and GPG2000 Approach and steps
    11. 11. Emissions from waste management <ul><li>Decomposition of organic matter in wastes (carbon and nitrogen) </li></ul><ul><li>Waste incineration (these emissions are not reported when waste is used to generate energy) </li></ul>
    12. 12. Decomposition of waste <ul><li>Anaerobic decomposition of man-made waste by methanogenic bacteria </li></ul><ul><ul><li>Solid waste </li></ul></ul><ul><ul><ul><li>Land disposal sites </li></ul></ul></ul><ul><ul><li>Liquid waste </li></ul></ul><ul><ul><ul><li>Human sewage </li></ul></ul></ul><ul><ul><ul><li>Industrial waste water </li></ul></ul></ul><ul><li>Nitrous oxide emissions from waste water are also produced from protein decomposition </li></ul>
    13. 13. Land disposal sites <ul><li>Major form of solid waste disposal in developed world </li></ul><ul><li>Produces mainly methane at a diminishing rate taking many years for waste to decompose completely </li></ul><ul><li>Also carbon dioxide and volatile organic compounds produced </li></ul><ul><li>Carbon dioxide from biomass not accounted or reported elsewhere </li></ul>
    14. 14. Decomposition process <ul><li>Organic matter into small soluble molecules (including sugars) </li></ul><ul><li>Broken down to hydrogen, carbon dioxide and different acids </li></ul><ul><li>Acids are converted to acetic acid </li></ul><ul><li>Acetic acid with hydrogen and carbon dioxide are substrate for methanogenic bacteria </li></ul>
    15. 15. Methane from land disposal <ul><li>Volumes </li></ul><ul><ul><li>Estimates from landfills: 20–70 Tg/yr </li></ul></ul><ul><ul><li>Total human methane emissions: 360 Tg/yr </li></ul></ul><ul><ul><li>From 6% to 20% of total </li></ul></ul><ul><li>Other impacts </li></ul><ul><ul><li>Vegetation damage </li></ul></ul><ul><ul><li>Odours </li></ul></ul><ul><ul><li>May form explosive mixtures </li></ul></ul>
    16. 16. Characteristics of the methanogenic process <ul><li>Highly heterogeneous </li></ul><ul><li>However, relevant factors to consider: </li></ul><ul><ul><li>Waste management practices </li></ul></ul><ul><ul><li>Waste composition </li></ul></ul><ul><ul><li>Physical factors </li></ul></ul>
    17. 17. Waste management practices <ul><li>Aerobic waste treatment </li></ul><ul><ul><li>Produces compost that may increase soil carbon </li></ul></ul><ul><ul><li>No methane </li></ul></ul><ul><li>Open dumping </li></ul><ul><ul><li>Common in developing regions </li></ul></ul><ul><ul><li>Shallow, open piles, loosely compacted </li></ul></ul><ul><ul><li>No control for pollutants, scavenging frequent </li></ul></ul><ul><ul><li>Anecdotal evidence of methane production </li></ul></ul><ul><ul><li>An arbitrary factor, 50% of sanitary land filling, is used </li></ul></ul>
    18. 18. Waste management practices (II) <ul><li>Sanitary landfills </li></ul><ul><ul><li>Specially designed </li></ul></ul><ul><ul><li>Gas and leakage control </li></ul></ul><ul><ul><li>Scale economy </li></ul></ul><ul><ul><li>Continued methane production </li></ul></ul>
    19. 19. Waste composition <ul><li>Degradable organic matter can vary </li></ul><ul><ul><li>Highly putrescible in developing countries </li></ul></ul><ul><ul><li>In developed countries, due to higher paper and card content, less putrescible </li></ul></ul><ul><li>This affects stabilization and methane production </li></ul><ul><ul><li>Developing countries: 10–15 years </li></ul></ul><ul><ul><li>Developed countries: more than 20 years </li></ul></ul>
    20. 20. Physical factors <ul><li>Moisture essential for bacterial metabolism </li></ul><ul><ul><li>Factors: initial moisture content, infiltration from surface and groundwater, as well as decomposition processes </li></ul></ul><ul><li>Temperature: 25–40°C required for a good methane production </li></ul>
    21. 21. Physical factors (II) <ul><li>Chemical conditions </li></ul><ul><ul><li>Optimal pH for methane production: 6.8 to 7.2 </li></ul></ul><ul><ul><li>Sharp decrease of methane production below 6.5 pH </li></ul></ul><ul><ul><li>Acidity may delay the onset of methane production </li></ul></ul><ul><li>Conclusion </li></ul><ul><ul><li>Data availability is too poor to use these factors for national or global methane emissions estimates </li></ul></ul>
    22. 22. Methane emissions <ul><li>Depend on several factors </li></ul><ul><li>Open dumps require other approaches </li></ul><ul><li>Availability and quality of relevant data </li></ul>
    23. 23. Waste-water treatment <ul><li>Produces methane, nitrous oxide and non-methane volatile organic compounds </li></ul><ul><li>May lead to storage of carbon through eutrophication </li></ul>
    24. 24. Methane emissions from waste-water treatment <ul><li>From anaerobic processes without methane recovery </li></ul><ul><li>Volumes </li></ul><ul><ul><li>30–40 Tg/yr </li></ul></ul><ul><ul><li>About 8%–11% of anthropogenic methane emissions </li></ul></ul><ul><ul><li>Industrial emissions estimated at 26–40 Tg/yr </li></ul></ul><ul><ul><li>Domestic and commercial estimated at 2 Tg/yr </li></ul></ul>
    25. 25. Factors for methane emissions <ul><li>Biochemical oxygen demand (BOD) (+/+) </li></ul><ul><li>Temperature ( >15°C) </li></ul><ul><li>Retention time </li></ul><ul><li>Lagoon maintenance </li></ul><ul><ul><li>Depth of lagoon ( >2.5 m, pure anaerobic; less than 1 m, not expected to be significant, most common facultative 1.2 to 2.5 m – 20% to 30% BOD anaerobically) </li></ul></ul>
    26. 26. Biochemical oxygen demand <ul><li>Is the organic content of waste water (“loading”) </li></ul><ul><li>Represents O consumed by waste water during decomposition (expressed in mg/l) </li></ul><ul><li>Standardized measurement is the “5-day test” denoted as BOD 5 </li></ul><ul><li>Examples of BOD 5 : </li></ul><ul><ul><li>Municipal waste water 110–400 mg/l </li></ul></ul><ul><ul><li>Food processing 10 000–100 000 mg/l </li></ul></ul>
    27. 27. Main industrial sources <ul><li>Food processing: </li></ul><ul><ul><li>Processing plants (fruit, sugar, meat, etc.) </li></ul></ul><ul><ul><li>Creameries </li></ul></ul><ul><ul><li>Breweries </li></ul></ul><ul><ul><li>Others </li></ul></ul><ul><li>Pulp and paper </li></ul>
    28. 28. Waste incineration <ul><li>Waste incineration can produce: </li></ul><ul><ul><li>Carbon dioxide, methane, carbon monoxide, nitrogen oxides, nitrous oxides and non-methane volatile organic compounds </li></ul></ul><ul><li>Nevertheless, it accounts for a small percentage of GHG output from the waste sector </li></ul>
    29. 29. Emissions from waste incineration <ul><li>Only the fossil-based portion of waste to be considered for carbon dioxide </li></ul><ul><li>Other gases difficult to estimate </li></ul><ul><ul><li>Nitrous oxide mainly from sludge incineration </li></ul></ul>
    30. 30. IPCC 1996GL <ul><li>Basis of inventory methodology for waste sector is: </li></ul><ul><ul><li>Organic matter decomposition </li></ul></ul><ul><ul><li>Incineration of fossil origin organic material </li></ul></ul><ul><li>Does not include concrete calculations for the latter </li></ul><ul><li>Organic matter decomposition covers: </li></ul><ul><ul><li>Methane from organic matter in both liquid and solid wastes </li></ul></ul><ul><ul><li>Nitrous oxide from protein in human sewage </li></ul></ul><ul><ul><li>Emissions of non-methane volatile organic compounds are not covered </li></ul></ul>
    31. 31. IPCC default categories <ul><li>Methane Emissions from Solid Waste Disposal Sites </li></ul><ul><li>Methane Emissions from Wastewater treatment </li></ul><ul><ul><li>Domestic and Commercial Wastewater </li></ul></ul><ul><ul><li>Industrial Wastewater and Sludge Streams </li></ul></ul><ul><li>Nitrous oxide from Human Sewage </li></ul>
    32. 32. Inventory preparation using IPCC 1996GL <ul><li>Step 1: Conduct key source category analysis for Waste sector where: </li></ul><ul><ul><li>Sector is compared to other source sectors such as Energy, Agriculture, LUCF, etc. </li></ul></ul><ul><ul><li>Estimate Waste sector’s share of national GHG inventory </li></ul></ul><ul><ul><li>Key source sector identification adopted by Parties that have already prepared an initial national communication, have inventory estimates </li></ul></ul><ul><ul><li>Parties that have not prepared an initial national communication can use inventories prepared under other programs/projects </li></ul></ul><ul><ul><li>Parties that have not prepared any inventory, may not be able to carry out the key source sector analysis </li></ul></ul><ul><li>Step 2: Select the categories </li></ul>
    33. 33. Inventory preparation using IPCC 1996GL (2) <ul><li>Step 3: Assemble required activity data depending on tier selected from local, regional, national and global databases, including EFDB </li></ul><ul><li>Step 4: Collect emission/removal factors depending on tier level selected from local/regional/national/global databases, including EFDB </li></ul><ul><li>Step 5: Select method of estimation based on tier level and quantify emissions/removals for each category </li></ul><ul><li>Step 6: Estimate uncertainty involved </li></ul><ul><li>Step 7: Adopt quality assurance/control procedures and report results </li></ul><ul><li>Step 8: Report GHG emissions </li></ul><ul><li>Step 9: Report all procedures, equations and sources of data adopted for GHG inventory estimation </li></ul>
    34. 34. Calculation of methane from solid waste disposal <ul><li>For sanitary landfills there are several methods: </li></ul><ul><ul><li>Mass balance and theoretical gas yield </li></ul></ul><ul><ul><li>Theoretical first order kinetics methodologies </li></ul></ul><ul><ul><li>Regression approach </li></ul></ul><ul><li>Complex models not applicable for regions or countries </li></ul><ul><li>Open dumps considered to emit 50%, but should be reported separately </li></ul>
    35. 35. Mass balance and theoretical gas yield <ul><li>No time factors </li></ul><ul><li>Immediate release of methane </li></ul><ul><li>Produces reasonable estimates if amount and composition of waste have been constant or slowly varying, otherwise biased trends </li></ul><ul><li>How to calculate: </li></ul><ul><ul><li>Using empirical formulae </li></ul></ul><ul><ul><li>Using degradable organic content </li></ul></ul>
    36. 36. Empirical formulae <ul><li>Assumes 53% of carbon content is converted to methane </li></ul><ul><li>If microbial biomass is discounted it reduces the amount emitted </li></ul><ul><li>234 m 3 of methane per tonne of wet municipal solid waste </li></ul>
    37. 37. Using degradable organic content (Base of Tier 1) <ul><li>Calculated from the weighted average of the carbon content of various components of the waste stream </li></ul><ul><li>Requires knowledge of: </li></ul><ul><ul><li>Carbon content of the fractions </li></ul></ul><ul><ul><li>Composition of the fractions in the waste stream </li></ul></ul><ul><li>This method is the basis for the Tier I calculation approach </li></ul>
    38. 38. Equation <ul><li>Methane emission = </li></ul><ul><ul><li>Total municipal solid waste (MSW) generated (Gg/yr) x </li></ul></ul><ul><ul><li>Fraction landfilled x </li></ul></ul><ul><ul><li>Fraction degradable organic carbon (DOC) in MSW x </li></ul></ul><ul><ul><li>Fraction dissimilated DOC x </li></ul></ul><ul><ul><li>0.5 g C as CH 4 /g C as biogas x </li></ul></ul><ul><ul><li>Conversion ratio (16/12) ) – Recovered CH 4 </li></ul></ul>
    39. 39. Assumptions <ul><li>Only urban populations in developing countries need be considered; rural areas produce no significant amount of emissions </li></ul><ul><li>Fraction dissimilated was assumed from a theoretical model that varies with temperature: 0.014T + 0.28, considering a constant 35°C for the anaerobic zone of a landfill, this gives 0.77 dissimilated DOC </li></ul><ul><li>No oxidation or aerobic process included </li></ul>
    40. 40. Example <ul><li>Waste generated 235 Gg/yr </li></ul><ul><li>% landfilled 80 </li></ul><ul><li>% DOC 21 </li></ul><ul><li>% DOC dissimilated 77 </li></ul><ul><li>Recovered 1.5 Gg/yr </li></ul><ul><li>Methane = (235*0.80*0.21*0.77*0.5*16/12) – 1.5 =19 Gg/yr </li></ul>
    41. 41. Limitations <ul><li>Main: </li></ul><ul><ul><li>No time factor </li></ul></ul><ul><ul><li>No oxidation considered </li></ul></ul><ul><li>DOC dissimilated too high </li></ul><ul><li>Delayed release of methane under increasing waste landfilled conditions leads to significant overestimations of emissions </li></ul><ul><li>Oxidation factor may reach up to 50% according to some authors, a 10% reduction is to be accounted </li></ul>
    42. 42. Default method – Tier 1 <ul><ul><li>Includes a methane correction factor according to the type of site (waste management correction factor). Default values range from 0.4 for shallow unmanaged disposal sites ( > 5m) to 0.8 for deep (<5m) unmanaged sites; and 1 for managed sites. Uncategorized sites given a correction factor of 0.6 </li></ul></ul><ul><ul><li>The former DOC dissimilated was reduced from 0.77 to 0.5 - 0.6, due to the presence of lignin </li></ul></ul>
    43. 43. Default method – Tier 1 <ul><li>The fraction of methane in landfill gas was changed from 0.5 to a range between 0.4 and 0.6, to account for several factors, including waste composition </li></ul><ul><li>Includes an oxidation factor. Default value of 0.1 is suitable for well managed landfills </li></ul><ul><li>It is important to remember to subtract recovered methane before applying an oxidation factor </li></ul>
    44. 44. Default method – Tier 1 Good Practice <ul><li>Emissions of methane (Gg/yr) = </li></ul><ul><ul><li>[(MSW T *MSW F *L 0 ) -R]*(1-OX) where </li></ul></ul><ul><ul><li>MSW T = Total municipal solid waste </li></ul></ul><ul><ul><li>MSW F = Fraction disposed at SWDS </li></ul></ul><ul><ul><li>L 0 = Methane generation potential </li></ul></ul><ul><ul><li>R = Recovered methane (Gg/yr) </li></ul></ul><ul><ul><li>OX = Oxidation factor (fraction) </li></ul></ul>
    45. 45. Methane generation potential <ul><ul><li>L 0 = (MCF*DOC*DOC F *F*16/12 (GgCH 4 /Gg waste)) </li></ul></ul><ul><ul><li>where: </li></ul></ul><ul><ul><ul><li>MCF = Methane correction factor (fraction) </li></ul></ul></ul><ul><ul><ul><li>DOC = Degradable organic carbon </li></ul></ul></ul><ul><ul><ul><li>DOC F = Fraction of DOC dissimilated </li></ul></ul></ul><ul><ul><ul><li>F = Fraction by volume of methane in landfilled gas </li></ul></ul></ul><ul><ul><ul><li>16/12 = Conversion from C to CH 4 </li></ul></ul></ul>
    46. 46. Other approaches <ul><li>Include a fraction of dry refuse in the equation </li></ul><ul><li>Consider a waste generation rate (1 kg per capita per day for developed countries, half of that for developing countries) </li></ul><ul><li>Use gross domestic product as an indicator of waste production rates </li></ul>
    47. 47. GPG2000 Approach
    48. 48. Theoretical first order kinetics methodologies (Tier 2) <ul><li>Tier 2 considers the long period of time involved in the organic matter decomposition and methane generation </li></ul><ul><li>Main factors: </li></ul><ul><ul><li>Waste generation and composition </li></ul></ul><ul><ul><li>Environmental variables (moisture content, pH, temperature and available nutrients) </li></ul></ul><ul><ul><li>Age, type and time since closure of landfill </li></ul></ul>
    49. 49. Base equation <ul><li>Q CH4 = L 0 R(e -kc - e -kt ) </li></ul><ul><ul><li>Q CH4 = methane generation rate at year t (m 3 /yr) </li></ul></ul><ul><ul><li>L 0 = degradable organic carbon available for </li></ul></ul><ul><ul><li>methane generation (m 3 /tonne of waste) </li></ul></ul><ul><ul><li>R = quantity of waste landfilled (tonnes) </li></ul></ul><ul><ul><li>k = methane generation rate constant (yr -1 ) </li></ul></ul><ul><ul><li>c = time since landfill closure (yr) </li></ul></ul><ul><ul><li>t = time since initial refuse placement (yr) </li></ul></ul>
    50. 50. Good practice equation <ul><li>Time t is replaced by t-x, normalization factor that corrects for the fact that the evaluation for a single year is a discrete time rather than a continuous time estimate </li></ul><ul><li>Methane generated in year t (Gg/yr) =  x [(A*k*MSW T (x)*MSW F (x)*L 0 (x)) * e -k(t-x) ] for x = initial year to t </li></ul><ul><li>Sum the obtained results for all years (x) </li></ul>
    51. 51. Good practice equation <ul><li>Where: </li></ul><ul><ul><li>t = year of inventory </li></ul></ul><ul><ul><li>x = years for which input should be added </li></ul></ul><ul><ul><li>A = (1-e -k )/k; normalisation factor which corrects the summation </li></ul></ul><ul><ul><li>k = Methane generation rate constant </li></ul></ul><ul><ul><li>MSW T (x)= Total municipal solid waste generated in year x (Proportional to total or urban population if no rural waste collection) </li></ul></ul><ul><ul><li>L 0 (x) = Methane generation potential </li></ul></ul>
    52. 52. Methane generation rate constant <ul><li>The methane generation rate constant k is the time taken for the DOC in waste to decay to half its initial mass (half-life) </li></ul><ul><li>k = ln2/t ½ </li></ul><ul><li>This requires historical data. Data for 3 to 5 half lives in order to achieve an acceptable result. Changes in management should be taken into account </li></ul>
    53. 53. Methane generation rate constant <ul><li>Is determined by type of waste and conditions </li></ul><ul><li>Measurements go from 0.03 to 0.2 per year, equivalent to half lives from 23 to 3 years </li></ul><ul><li>More degradable material and humidity lower half life </li></ul><ul><li>Default value: 0.05 per year, or a half life of 14 years </li></ul>
    54. 54. Methane generation potential <ul><ul><li>L 0 (x) = (MCF(x)*DOC(x)*DOC F *F*16/12 (GgCH 4 /Gg waste)) </li></ul></ul><ul><ul><li>where: </li></ul></ul><ul><ul><ul><li>MCF(x) = Methane correction factor in year x (fraction) </li></ul></ul></ul><ul><ul><ul><li>DOC (x) = Degradable organic carbon in year x </li></ul></ul></ul><ul><ul><ul><li>DOC F = Fraction of DOC dissimilated </li></ul></ul></ul><ul><ul><ul><li>F = Fraction by volume of methane in gas generated from landfill </li></ul></ul></ul><ul><ul><ul><li>16/12 = Conversion from C to CH 4 </li></ul></ul></ul>
    55. 55. Methane emitted <ul><li>Methane generated minus methane recovered and not oxidized </li></ul><ul><li>Equation: </li></ul><ul><ul><li>Methane emitted in year t (Gg/yr) = (Methane generated in year t (Gg/yr) - R(t))*(1 - Ox) </li></ul></ul><ul><ul><li>Where: </li></ul></ul><ul><ul><li>R(t) = Methane recovered in year t (Gg/yr) </li></ul></ul><ul><ul><li>Ox = Oxidation factor (fraction) </li></ul></ul>
    56. 56. Practical applications <ul><li>Base for Tier 2 approach </li></ul><ul><li>Applied earlier in: </li></ul><ul><ul><li>United Kingdom </li></ul></ul><ul><ul><li>The Netherlands </li></ul></ul><ul><ul><li>Canada </li></ul></ul>
    57. 57. Regression approach <ul><li>From empirical models </li></ul><ul><li>Statistical and regressional analysis applied </li></ul>
    58. 58. Uncertainties in calculations <ul><li>Methane actually produced </li></ul><ul><ul><li>Are old landfills covered? </li></ul></ul><ul><li>Quantity and composition of landfilled waste </li></ul><ul><ul><li>Is there historical data on waste composition? </li></ul></ul><ul><li>Methane actually produced </li></ul><ul><ul><li>Are landfill and waste management practices well known? </li></ul></ul>
    59. 59. Calculations of emissions from waste-water treatment <ul><li>Calculations for industrial and domestic and commercial waste water are based on biochemical oxygen demand ( BOD) loading </li></ul><ul><li>Standard methane conversion factor 0.22 Gg CH 4 /Gg BOD is recommended </li></ul><ul><li>For nitrous oxide and methane it is possible to base calculation on total volatile solids and apply the simple method used in the agriculture sector </li></ul>
    60. 60. Methane from domestic and commercial waste water <ul><li>Simplified approach </li></ul><ul><li>Data: </li></ul><ul><ul><li>BOD in Gg per 1000 persons (default values) </li></ul></ul><ul><ul><li>Country population in thousands </li></ul></ul><ul><ul><li>Fraction of total waste water treated anaerobically (0.1–0.15 as default) </li></ul></ul><ul><ul><li>Methane emission factor (default 0.22 Gg CH 4 /Gg BOD </li></ul></ul><ul><ul><li>Subtract recovered methane </li></ul></ul>
    61. 61. Equation <ul><li>Methane emission = </li></ul><ul><li>Population (10 3 ) x </li></ul><ul><li>Gg BOD 5 /1000 persons x </li></ul><ul><li>Fraction anaerobically treated x </li></ul><ul><li>0.22 Gg CH 4 /Gg BOD – </li></ul><ul><li>Methane recovered </li></ul>
    62. 62. GPG 2000 Approach
    63. 63. Good practice guidance – Check method <ul><li>WM = P*D*SBF*EF*FTA*365*10 -12 , where: </li></ul><ul><ul><li>WM = country’s annual methane emissions from domestic waste water </li></ul></ul><ul><ul><li>P = population (total or urban in developing countries) </li></ul></ul><ul><ul><li>D = organic load (default 60 g BOD/person/day) </li></ul></ul><ul><ul><li>SBF = fraction of BOD that readily settles, default = 0.5 </li></ul></ul><ul><ul><li>EF = emission factor (g CH 4 / g BOD), default = 0.6 or 0.25 g CH 4 / g COD (chemical oxygen demand) when using COD </li></ul></ul><ul><ul><li>FTA = part of BOD anaerobically degraded, default = 0.8 </li></ul></ul>
    64. 64. Check method rationale <ul><li>SBF is related to BOD from non-dissolved solids, which account for more than 50% of BOD. Settling tanks remove 33% and other methods 50% </li></ul><ul><li>Fraction of BOD in sludge that degrades anaerobically (FTA) is related to the processes, aerobic or anaerobic. Aerobic processes and sludge non-methane producing procedures may lead to FTA = 0 </li></ul>
    65. 65. Check method rationale <ul><li>Emission factor is expressed in BOD, however COD is used in many places </li></ul><ul><li>COD is 2 to 2.5 times higher than BOD, so the default values are 0.6 g CH 4 / g BOD or 0.25 g CH 4 / g COD </li></ul><ul><li>Emission factor is calculated from the methane producing factor stated above and the weighted average of methane conversion factor (MCF) </li></ul>
    66. 66. Methane conversion factor <ul><li>IPCC guidelines recommends to separate calculations for waste water and sludge. This influences the detailed approach calculation </li></ul><ul><li>Excepting sludge sent to landfills or for agriculture, this is not necessary </li></ul><ul><li>If no data are available, expert judgement of sanitation engineers may be incorporated: Weighted MCF = Fraction of BOD anaerobically degrades </li></ul>
    67. 67. Detailed approach <ul><li>Considers two additional factors: </li></ul><ul><ul><li>Different treatment methods used and total waste water treated using each method </li></ul></ul><ul><ul><li>MCF for each treatment </li></ul></ul><ul><li>The final result is the sum of the fractions calculated by the simplified approach, less the recovered methane </li></ul>
    68. 68. Equation <ul><li>Domestic and commercial waste-water emissions = </li></ul><ul><li>(   Methane calculated by simplified approach x </li></ul><ul><li>Fraction waste water treated using method i x MCF for method i) - methane recovered </li></ul>
    69. 69. Methane emissions from industrial waste water <ul><li>Industrial waste water may be treated in domestic sewer systems or on site </li></ul><ul><li>Only on-site calculations are covered in this section, the rest should be added to domestic waste-water loading </li></ul><ul><li>Most estimates used are for point sources </li></ul><ul><li>Focus on key industries is required and default values are provided </li></ul>
    70. 70. Emissions from industrial waste-water treatment <ul><li>Simplified approach: </li></ul><ul><ul><ul><li>Determine relevant industries (wine, beer, food, paper, etc.) </li></ul></ul></ul><ul><ul><ul><li>Estimate waste-water outflow (per tonne of product, or default) </li></ul></ul></ul><ul><ul><ul><li>Estimate BOD 5 concentration (or default) </li></ul></ul></ul><ul><ul><ul><li>Estimate the fraction treated </li></ul></ul></ul><ul><ul><ul><li>Estimate methane emission factor (default 0.22 Gg CH 4 /Gg BOD ) </li></ul></ul></ul><ul><ul><ul><li>Subtract any methane recovered </li></ul></ul></ul>
    71. 71. Equation <ul><li>Industrial waste-water emissions = </li></ul><ul><li>(    waste-water outflow by industry (Ml/yr) x </li></ul><ul><li>kg BOD 5 /I x </li></ul><ul><li>Fraction waste water treated anaerobically x 0.22) - Methane recovered </li></ul>
    72. 72. Detailed approach <ul><li>Similar to the used for estimating methane emissions from domestic and commercial waste water </li></ul><ul><li>Requires knowledge of: </li></ul><ul><ul><li>Specific waste-water treatments </li></ul></ul><ul><ul><li>MCF for each factor </li></ul></ul>
    73. 73. Equation <ul><li>Industrial waste-water Emissions = </li></ul><ul><li>(    Waste-water outflow by industry (Ml/yr) x </li></ul><ul><li>kg BOD 5 /l x </li></ul><ul><li>Fraction waste water treated using method i x MCF for method i) - Methane recovered </li></ul>
    74. 74. Uncertainties in calculations <ul><ul><li>Lack of information about volumes, treatments and recycling </li></ul></ul><ul><ul><li>Discharge into surface waters: </li></ul></ul><ul><ul><ul><li>Not anaerobic (default 0%) </li></ul></ul></ul><ul><ul><ul><li>Anaerobic (default 50%) </li></ul></ul></ul><ul><ul><li>Septic tanks (long retention times: more than 6 months) </li></ul></ul><ul><ul><ul><li>Long retention of solids (default 50%) </li></ul></ul></ul><ul><ul><ul><li>Short retention of solids (default 10%) </li></ul></ul></ul><ul><ul><li>Open pits and latrines (default 20%) </li></ul></ul><ul><ul><li>Other limitations: BOD, temperature, pH and retention time </li></ul></ul>
    75. 75. GPG2000 Approach
    76. 76. Emissions from waste incineration <ul><li>For carbon dioxide, only fossil fraction counts not biomass </li></ul><ul><li>Only accounted under waste sector when no energy is recovered </li></ul><ul><li>IPCC guidelines include a simple method </li></ul><ul><ul><li>It is good practice to disaggregate waste into waste types and take into account burn-out efficiency of incinerator </li></ul></ul>
    77. 77. Equation for carbon dioxide <ul><ul><li>CO 2 emission (Gg/yr) =  i (IW i *CCW i *FCF i *Ef i *44/12) </li></ul></ul><ul><ul><li>where i = MSW, HW, CW, SS </li></ul></ul><ul><ul><li>MSW municipal solid waste, HW hazardous waste, CW clinical waste and SS sewage sludge </li></ul></ul><ul><ul><li>IW i = Amount of incinerated waste type i </li></ul></ul><ul><ul><li>CCW i = Fraction of C content in waste type i </li></ul></ul><ul><ul><li>FCF i = Fraction of fossil C in waste type i </li></ul></ul><ul><ul><li>EF = Burn-out efficiency of combustion of incinerators for waste type i (fraction) </li></ul></ul><ul><ul><li>44/12 = Conversion from C to CO 2 </li></ul></ul>
    78. 78. Equation for nitrous oxide <ul><ul><li>N 2 O emission (Gg/yr) =  i (IW i *Ef i )*10 -6 where </li></ul></ul><ul><ul><li>IW i = Amount of incinerated waste type i (Gg/yr) </li></ul></ul><ul><ul><li>EF i = Aggregate emission factor for waste type i (kg N 2 O/Gg) or </li></ul></ul><ul><ul><li>N 2 O emission (Gg/yr) =  i (IW i *EC i *FGV i )*10 -9 </li></ul></ul><ul><ul><li>IW i = Amount of incinerated waste type i (Gg/yr) </li></ul></ul><ul><ul><li>EC i = N 2 O emission concentration in flue gas from waste of type i (mg N 2 O /Mg) </li></ul></ul><ul><ul><li>FGV i = Flue gas volume by amount of incinerated waste type i (m 3 /Mg) </li></ul></ul>
    79. 79. Emission factors and activity data for carbon dioxide <ul><ul><li>C content varies: sewage sludge, 30%; municipal solid waste, 40%; hazardous waste, 50%; and clinical waste, 60%. </li></ul></ul><ul><ul><li>It is assumed that there is very little <<virtually no>> fossil carbon in sewage sludge, 0%; high content in clinical and municipal, 40%; and very high content in hazardous waste, 90% </li></ul></ul><ul><ul><li>The efficiency of combustion is 95% for all waste streams, except hazardous, which is 99.5% </li></ul></ul>
    80. 80. Emission factors and activity data for nitrous oxide <ul><li>Emission factors differ with facility type and type of waste </li></ul><ul><li>Default factors can be used </li></ul><ul><li>Consistency and comparability are difficult due to heterogeneous waste types across countries </li></ul>
    81. 81. Reporting framework
    82. 82. General reporting recommendations <ul><li>It is good practice to document and archive all information required to produce the national inventory estimates </li></ul><ul><li>See GPG2000, Chapter 8, Quality Assurance and Quality Control, Section 8.10.1, Internal Documentation and Archiving </li></ul><ul><li>Transparency in activity data and the possibility to retrace calculations are important </li></ul>
    83. 83. Report quality assurance/quality control <ul><li>Transparency can be improved through clear documentation and explanations </li></ul><ul><ul><li>Estimate using different approaches </li></ul></ul><ul><ul><li>Cross check emission factors </li></ul></ul><ul><ul><li>Check default values, survey data and secondary data preparation for activity data </li></ul></ul><ul><ul><li>Cross check with other countries </li></ul></ul><ul><li>Involve industry and government experts in review processes </li></ul>
    84. 84. Reporting for methane from solid waste disposal sites <ul><ul><li>If Tier 2 is applied, historical data and k values should be documented, and closed landfills should be accounted for </li></ul></ul><ul><ul><li>Distribution of waste (managed and unmanaged) for MCF should be documented </li></ul></ul><ul><ul><li>Comprehensive landfill coverage, including industrial, sludge disposal, construction and demolition waste sites is recommended </li></ul></ul>
    85. 85. Reporting for methane from solid waste disposal sites <ul><ul><li>If methane recovery is reported an inventory is desirable. Flaring and energy recovery should be documented separately </li></ul></ul><ul><ul><li>Changes in parameters should be explained and referenced </li></ul></ul><ul><ul><li>Time series should apply the same methodology; if there are changes it is required to recalculate the entire time series to achieve consistency in trends (See GPG2000, Chapter 7,, Alternative recalculation techniques) </li></ul></ul>
    86. 86. Reporting for methane from domestic waste-water handling <ul><li>Function of human population and waste generation per person, expressed as biochemical oxygen demand </li></ul><ul><li>If in rural areas, only aerobical disposal; only urban population is accounted for </li></ul><ul><li>COD*2.5 = BOD </li></ul><ul><li>Recalculate whole time series </li></ul><ul><li>Calculations need to be retraced, particularly if there are changes to MCFs </li></ul>
    87. 87. Reporting for methane from industrial waste-water handling <ul><ul><li>Industrial estimates are accepted if they are transparent and consistent with QA/QC </li></ul></ul><ul><ul><li>Recalculations need to be consistent over time </li></ul></ul><ul><ul><li>Default data for industrial waste water is in GPG2000, Chapter 5, Table 5.4 </li></ul></ul><ul><ul><li>Sectoral tables and a detailed inventory report are necessary to provide transparency </li></ul></ul>
    88. 88. Reporting nitrous oxide emissions from waste water <ul><li>Based on IPCC Guidelines, Chapter 4, Agriculture, Section 4.8, Indirect N 2 O emissions from nitrogen used in agriculture </li></ul><ul><li>Future work on data, approaches and calculations is needed </li></ul>
    89. 89. Reporting for waste incineration <ul><li>All waste incineration is to be included </li></ul><ul><li>Avoid double counting with energy recovery, even when waste is used as a substitute fuel (e.g. cement and brick production) </li></ul><ul><li>Default ranges for emission estimates are provided in GPG2000, Chapter 5, Tables 5.6 and 5.7 </li></ul><ul><li>Support fuel, generally little, shall be reported in Energy sector; maybe important for hazardous waste </li></ul>
    90. 90. Key source category analysis and decision trees
    91. 91. Comparison
    92. 92. Comparison between IPCC 1996GL and GPG2000 Contains no detailed methodologies <<correct?>> <ul><li>New section including emissions from waste incineration covers: </li></ul><ul><li>CO 2 emissions </li></ul><ul><li>N 2 O emissions </li></ul>Calculation made on the basis of an approximation developed for the Agriculture sector (see chapter on Agriculture sector) Human sewage is indicated as an area for further development and no improvement over IPCC 1996GL is presented <ul><li>Keeps a separation between: </li></ul><ul><li>Domestic waste water </li></ul><ul><li>Industrial waste water </li></ul>Includes a “check method” for countries with difficulties to calculate the emissions from domestic waste-water handling Based on last year’s waste entering the disposal sites. Good approximation only for long-term stable conditions. First Order Decay is mentioned without specific calculations First Order Decay Method for Solid Waste Disposal Sites based on real- world conditions of decomposition IPCC 1996GL - default approach GPG2000
    93. 93. Key activity data required for GPG2000 and IPCC 1996GL <ul><li>Disposal activity for current year, default values or a per capita approach </li></ul><ul><li>Waste-water flows and waste-water treatment data required </li></ul><ul><li>Very detailed, industry specific data required </li></ul><ul><li>No specific methodology </li></ul><ul><li>Disposal activity for solid waste for several years </li></ul><ul><li>Less requirements with the check method for CH 4 emissions from domestic waste water </li></ul><ul><li>Top-down modification of IPCC 1996GL recommended due to high costs </li></ul><ul><li>Incineration amounts, composition (carbon content and fossil fraction) required for CO 2 </li></ul><ul><li>Emission measurements recommended for N 2 O </li></ul>IPCC 1996GL GPG2000
    94. 94. Key emission factors required for IPCC 1996GL and GPG2000 <ul><li>Most emission factors are common to both: </li></ul><ul><ul><li>Methane generation potential for SWDS </li></ul></ul><ul><ul><li>Human sewage conversion factor </li></ul></ul><ul><ul><li>Methane conversion factor </li></ul></ul><ul><li>New emission factors related to: </li></ul><ul><ul><li>Tier 2 for SWDS, particularly k value </li></ul></ul><ul><ul><li>Waste incineration (lack of some default values) </li></ul></ul>
    95. 95. Link between IPCC 1996GL and GPG2000 <ul><li>GPG2000 uses the same tables as were provided in IPCC 1996GL, based on the same categories </li></ul>
    96. 96. List of problems
    97. 97. Problems addressed <ul><li>Problems found by NAI experts in using IPCC 1996GL </li></ul><ul><li>Problems categorized into: </li></ul><ul><ul><li>Methodological issues </li></ul></ul><ul><ul><li>Activity data (AD) </li></ul></ul><ul><ul><li>Emission factors (EF) </li></ul></ul><ul><li>GPG2000 addresses some deficiencies found in IPCC 1996GL </li></ul><ul><ul><li>Strategies for improvement in methodology, AD and EF </li></ul></ul><ul><ul><li>Strategy for AD and EF – tier approach </li></ul></ul><ul><ul><li>Points to sources of data for AD and EF, including EFDB </li></ul></ul>
    98. 98. Methodological issues <ul><li>Methodologies that are not covered : </li></ul><ul><ul><li>Sludge spreading and composting, </li></ul></ul><ul><ul><li>Use of burning under conditions not reflected properly in the waste incineration section </li></ul></ul><ul><ul><li>Tropical conditions of many NAI Parties vis-à-vis methane generation </li></ul></ul><ul><ul><li>Use of open dumps instead of landfills </li></ul></ul><ul><ul><li>Lack of a proper calculation method for human sewage in the case of island countries or countries with prevailing coastal populations, and complexity of the methodology. </li></ul></ul>
    99. 99. Lack of waste methodologies that reflect national circumstances - Initiate field studies to generate methodologies, or use approaches proposed by Annex 1 countries for these categories. - Expand the proper sections to reflect the conditions prevailing in many NAI countries. <ul><li>The GPG2000 does not cover composting and sludge spreading, which are common practices in NAI countries </li></ul><ul><li>Burning and open dump processes are not well covered by GPG2000 and are frequent practices in NAI countries. </li></ul>Improvement suggested GPG2000 approach
    100. 100. More deficiencies in the methodologies - Initiate field studies to expand the methodology - Adopt the proposed methodologies covered in the Agriculture chapter differentiating according to geographical reality - The GPG2000 does not cover conditions for tropical countries and management practices for both solid wastes and waste waters - The approximation used in GPG2000 to calculate nitrous oxide from human sewage (the same approximation as in IPCC 1996GL) does not reflect properly the situation of coastal/island areas Improvement suggested GPG2000 approach
    101. 101. Complexity of methodology - Methods similar to the Check method for waste water should be provided to enhance completeness of reporting - The methodologies presented for Solid Waste Disposal Sites and Waste Incineration require data that are not commonly available in NAI countries Improvement suggested GPG2000 approach
    102. 102. Activity data problems Low reliability and high uncertainty of data Extrapolations based on past data used to apply Tier 2 for Solid Waste Disposal Sites CH 4 generation Lack of data on oxidation conditions Lack of data on composition of solid waste Lack of availability of disaggregated data Lack of time-series data for waste generation Lack of data on generated solid waste
    103. 103. Emission factor problems Default data commonly provides upper value, leading to overestimation Lack of emission factors in IPCC 1996GL for waste incineration (covered by GPG 2000) Low reliability and high uncertainty of data Lack of availability of methane conversion factors for certain NAI regions Lack of emission factors at disaggregated level Default data not suitable for national circumstances Inappropriate default values given in IPCC 1996GL
    104. 104. List of problems (Category wise)
    105. 105. CH 4 Emissions from Solid Waste Disposal Sites Table 6.A
    106. 106. Methodological issues <ul><li>Use of open dumps or open incineration </li></ul><ul><li>Recycling, commonly of wood and paper but even of organic waste </li></ul>
    107. 107. Activity data and emission factors <ul><li>Lack of activity data, both for the present and the required time series, for the waste flows and their composition </li></ul><ul><li>Default activity data for only 10 NAI countries </li></ul><ul><li>Values reflected for k parameter for the application of the First Order Decay method do not reflect tropical conditions of temperature and humidity. The higher k value in GPG2000 is 0.2 and the one in IPCC 1996GL is 0.4 </li></ul><ul><li>The proposed Methane Correction Factor, even using the lesser value, 0.4, may lead to overestimations, due to shallowness and the frequent practice of burning as a pretreatment at disposal sites </li></ul>
    108. 108. Emissions from Wastewater Handling Table 6.B
    109. 109. Methodological issues <ul><li>For CH 4 emissions from domestic waste-water handling, GPG2000 presents a simplified method called the “check method” avoiding the complexities in IPCC 1996GL </li></ul><ul><li>In NAI countries, national methods or parameters, or even activity data, may by available only infrequently </li></ul><ul><li>For CH 4 emissions from industrial waste-water handling, GPG2000 presents a “best practice” for cases where these emissions represent a key source, recommending the selection of 3 or 4 key industries </li></ul><ul><li>For emissions of N 2 O from human sewage, no improvements were made in GPG2000 over IPPC 1996 GL. This methodology has several limitations that have caused several NAI countries to declare it “inapplicable” </li></ul>
    110. 110. Activity data and emission factors <ul><li>Availability of activity data and emission factors is uncommon in NAI countries for CH 4 emissions from domestic waste water, and the “check method” may help to overcome this issue. In any case, GPG 2000 is an improvement in that it identifies potential CH 4 emissions </li></ul><ul><li>For CH 4 emissions from industrial waste water, in cases where it is a key source, it is feasible to work only with the largest industries </li></ul><ul><li>For N 2 O emissions from human sewage, the activity data needed are relatively simple and easy to obtain </li></ul>
    111. 111. Emissions from Waste Incineration Table 6.C
    112. 112. Methodological issues <ul><li>This source category was only briefly introduced in the IPCC 1996GL, but is fully developed in the GPG2000 </li></ul><ul><li>In NAI countries, incineration of waste (other than clinical waste) is uncommon due to high costs </li></ul><ul><li>Differentiation is made between CO 2 and N 2 O because the former is calculated with a mass balance approach and the latter depends on operating conditions </li></ul>
    113. 113. Activity data and emission factors <ul><li>GPG2000 recognizes the difficulties in finding activity data to differentiate the four proposed categories (municipal, hazardous, clinical and sewage sludge) </li></ul><ul><li>Do not request differentiation if data are not available when it is not a key source category </li></ul>
    114. 114. Review and assessment of activity data and emission factors: data status and options
    115. 115. Status of EFDB for the Waste sector <ul><li>EFDB is an emerging database </li></ul><ul><li>All experts are expected to contribute to EFDB. </li></ul><ul><li>Currently it contains only limited information on Waste sector emission factors </li></ul><ul><li>In future, with contributions from experts around the world, EFDB should become a reliable source of data for emission factors for GHG inventory </li></ul>
    116. 116. EFDB – Waste sector status 353 Total (as at October 2004) 0 Other (6D) 47 Waste Incineration (6C) 191 Wastewater Handling (6B) 115 Solid Waste Disposal on Land (6A) Emission factor records IPCC 1996GL category
    117. 117. Uncertainty estimation and reduction
    118. 118. Uncertainty estimation and reduction <ul><li>The good practice approach requires that estimates of GHG inventories be accurate </li></ul><ul><ul><li>they should neither be over- nor underestimated as far as can be judged </li></ul></ul><ul><li>Causes of uncertainty could include: </li></ul><ul><ul><li>unidentified sources </li></ul></ul><ul><ul><li>lack of data </li></ul></ul><ul><ul><li>quality of data </li></ul></ul><ul><ul><li>lack of transparency </li></ul></ul>
    119. 119. Reporting uncertainties from solid waste disposal sites <ul><li>Main uncertainty sources: </li></ul><ul><ul><ul><li>Activity data (total municipal waste MSW T and fraction sent to disposal sites MSW F ) </li></ul></ul></ul><ul><ul><ul><li>Emission factors (methane generation rate constant) </li></ul></ul></ul><ul><li>Other factors listed in GPG2000, Table 5.2: </li></ul><ul><ul><ul><li>Degradable organic carbon, fraction of degradable organic carbon, methane correction factor, fraction of methane in landfill gas </li></ul></ul></ul><ul><ul><ul><li>Possibly also methane recovery and oxidation factor </li></ul></ul></ul>
    120. 120. Reporting uncertainties from domestic waste-water handling <ul><li>Uncertainties are related to BOD/person, maximum methane producing capacity and fraction treated anaerobically (data for population has little uncertainty ( + 5%)) </li></ul><ul><li>Default ranges are: </li></ul><ul><ul><li>BOD/person and maximum methane producing capacity ( + 30%) </li></ul></ul><ul><li>For fraction treated anaerobically use expert judgement </li></ul>
    121. 121. Reporting uncertainties from industrial waste-water treatment <ul><li>Uncertainties are related to industrial production, COD/unit waste water (from -50% to +100%), maximum methane producing capacity and fraction treated anaerobically </li></ul><ul><li>Default ranges are: </li></ul><ul><ul><li>industrial production ( + 25%) </li></ul></ul><ul><ul><li>maximum methane producing capacity ( + 30%) </li></ul></ul><ul><li>For fraction treated anaerobically use expert judgement </li></ul>
    122. 122. Reporting uncertainties from waste incineration <ul><li>Activity data uncertainty on amount of incinerated waste assumed to be low ( + 5%) in developed countries. Some wastes, such as clinical waste, may be higher </li></ul><ul><li>Major uncertainty for CO 2 is fossil carbon fraction </li></ul><ul><li>For N 2 O default values, uncertainty is as high as 100% </li></ul>