1 / 19

Introduction to 2006-IPCC guidelines

Workshop CH4 from waste, March 8th -9th, 2006. Introduction to 2006-IPCC guidelines. In the next hour. Changes compared to previous methods Some backgrounds Why 1st order decay model (FOD) Changed mathematics FOD Single-phase vs. multi-phase Why default oxidation

dash
Télécharger la présentation

Introduction to 2006-IPCC guidelines

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Workshop CH4 from waste, March 8th -9th, 2006 Introduction to 2006-IPCC guidelines Intro IPCC-model, Copenhagen

  2. In the next hour • Changes compared to previous methods • Some backgrounds • Why 1st order decay model (FOD) • Changed mathematics FOD • Single-phase vs. multi-phase • Why default oxidation • Measuring and estimating recovery • Default values • Introduction to the spreadsheet-model Intro IPCC-model, Copenhagen

  3. Methane emissions emission = (formation – recovery)*(1-oxidation) Intro IPCC-model, Copenhagen

  4. Most important changes compared to ‘96 RG and ‘00 GPG • Improved estimate of waste and DOC • 1st order decay model (FOD) strongly recommended • and facilitated in a model • slightly different mathematics FOD • improved default values • Waste generation • Waste composition • Model parameters • recovery preferably measured, conservative estimation methodology introduced • C-storage, harvested wood in landfill Intro IPCC-model, Copenhagen

  5. Estimating DOC landfilled Default values for • MSW-produced • Other wastes produced • Composition waste • DOC-content waste fractions • Fraction landfilled • Historical development amounts waste Intro IPCC-model, Copenhagen

  6. Estimating DOC landfilled (2) Bulk waste approach: • Little information available • MSW-generated * % landfilled = MSW landfilled • MSW landfilled * DOCMSW = DOC in MSW landfilled Intro IPCC-model, Copenhagen

  7. Estimating DOC landfilled (3) Material stream approach: • Country specific information available • MSW-generated * % landfilled = MSW landfilled • MSW landfilled * % food waste = food waste landfilled • Food waste landfilled * DOCfw = DOC in food landfilled Intro IPCC-model, Copenhagen

  8. Calculation of methane formation • Methane potential as in ‘96-RG and ’00-GPG L0 = 0,5 * 16/12 * DOCf * DOC * MCF • Defaults for DOCf and MCF • Delayed release of methane potential: first order decay (FOD)-model Intro IPCC-model, Copenhagen

  9. Why FOD? • Methane is formed throughout decades • Starting point emission inventory: ‘where and when’ • GPG, 2000: ‘Important when practices change rapidly’ • GPG, 2000: ‘1996-default method overestimates effect of reduced landfilling in the period 1990-2010, FOD is good practice’ • For transparency reasons FOD for all countries Intro IPCC-model, Copenhagen

  10. Better estimation of emission reduction Intro IPCC-model, Copenhagen

  11. Better estimation of emission reduction (2) Intro IPCC-model, Copenhagen

  12. Changes to ‘96-guidelines/’00-GPG • Facilitated by development of internet • More complicated methodology • Still easy to use • Reason for changes Intro IPCC-model, Copenhagen

  13. Changes in algorithm • FOD 1996: formation = L0 * k * e-kt (1) • GPG ’00: correction factor • FOD 2006: formation = L0* (e-k(t-1)-e-kt) (2) • Validated older models (1) are not „wrong“ Intro IPCC-model, Copenhagen

  14. Single-phase vs. Multi-phase • Waste is not waste but food, paper, wood, etc. • Single-phase • Average k-value for all streams • Reactions are fully dependent • Decay of food waste is delayed and wood waste is accelerated • Multi-phase • Discrete k-values for each stream • Reactions are fully independent • Wood is wood and degrades as wood, irrespective of other wastes present Intro IPCC-model, Copenhagen

  15. Single-phase vs. Multi-phase (2) • Truth will lie in the middle • No experimental support for either of both options • No theoretical support for either of both • Both options are facilitated in the model Intro IPCC-model, Copenhagen

  16. Recovery Starting point ‘00 GPG: • only measured amounts recovered!!!!! • (recovery estimates tend to be way too optimistic) ’06-guidelines: • Measurements highly recommended • Conservative default estimation methods introduced • 20% recovery efficiency • 35% of installed capacity Intro IPCC-model, Copenhagen

  17. Recovery (2) Few measurements available: • 10-85% efficiency (Netherlands: 37% average) • However mostly closed landfills Most relevant landfills still have parts in exploitation Conservative default efficiency: ~20% (Dutch experience, to my opinion not that conservative) Intro IPCC-model, Copenhagen

  18. Recovery (3) Recovery and flare capacity • Conservative default utilisation factor: 35% • Based on US and Dutch experiences Main reasons for non-use • Overestimated gas formation – Overdesigned equipment • Poor working hours (down to 80%) • Back-up systems Intro IPCC-model, Copenhagen

  19. Oxidation default value: 10% No change compared to ’96-RG and ’00-GPG May be higher, but highly uncertain • Very difficult to measure • 13C-analysis • CO2 and CH4 mass balance • Heterogeneous pathway of emissions due to cracks, etc. • Highly variable (CH4-flux, soil-type, vegetation) • Dependent on climatological conditions, season • Few data available Intro IPCC-model, Copenhagen

More Related