Introduction. Development of Application Procedure of the Tier 2 Methodology for CH 4 Emission from Korean Landfills HALLYM UNIVERSITY

Transcription

1 Development of Application Procedure of the Tier 2 Methodology for CH 4 Emission from Korean Landfills Seungdo Kim Dept. of Environmental System Eng. Hallym University Introduction 1

2 Hierarchy of Solid Waste Management in Korea Reduction Reuse Recycling Energy Recovery Incineration Landfill Treatment Trend of Municipal Solid Waste in Korea Year Landfill Incineration Recycling (% ) (% ) (% )

3 ombustiblesnon-combustiblesrecyclablesmunicipalsolidwastemsw Compositional Generation Rate(2001 year) Item ItemCTotal (ton/day) Sum (ton/da y) Food wastes (%) Generation 48, , Landfill 21, , Inci neration 6, , Recycling 20, , Papers (%) Woods (%) Rubber &Leather (%) Plastics (%) Others (%) Sum (ton/da y) 5, , Briquette ash (%) ㅡ 8.48 Metals & Glasses (%) Earth & Sand (%) Others (%) Sum (ton/da y) 14, , Papers(%) Glasses (%) ㅡ Metals (%) ㅡ Cans (%) ㅡ Plastics (%) Others (%) Management Schemes of MSW in Korea Source Separation MSW Recycling No Yes Food wastes Aerobic digestion Anaerobic digestion Animal feeding Others Papers Plastics Meta ls Inorganic wastes Organic wastes Landfill Ash Incineration 3

4 Estimation Methodology of CH 4 from Landfill : Tier 2 Questions to be Answered Why should we apply the Tier 2? How much the accuracy may be improved as a result of applying the Tier 2? What would be the most efficient approaches to adopt the Tier 2? 4

5 Methane Emission from Landfill: (1) Extraction Well, (2) Surface Diffusion Recovery of Me thane A Extraction Well B Surface Diffusion Crack or Weak Point Emission Pattern of CH 4 from Landfill over time Composite Generation Pattern of CH 4 CH 4 emission from solid waste landfilled durin g the 1 st year 2 nd year 3rd ye ar Generation Rate of CH 4 (ton/yr) Year 5

6 Methodologies suggested by IPCC Tier 1 CH 4 (ton/yr) = (MSW T x MSW F x MCF x DOC x DOC F x F x 16/12 R) x (1-OX) Assumptions (1) CH 4 generated by the waste is released in the same year the waste is deposited (2) Landfilled amount is relatively constant over time If waste disposal increases at about 2% per year over a 20~30 year period, the Tier 1 method would overestimate emissions by about 20~25%. Methodologies suggested by IPCC Tier 2 Q CH = L 0 Mt {exp( kc) exp( kt)} 4 Basics L 0 : Methane Generation Potential M t : Annual amount of solid waste landfilled k : Methane generation constant (yr -1 ) (1) CH 4 is emitted over a long period of time rather than instantaneously (2) First-order decay model has been broadly used to model generation rate of CH 4 from landfills 6

7 Decision Tree for CH 4 Emissions from Solid Waste Disposal Sites What are the difficulties in applying the Tier 2? Lack of information on MSW landfilled previously resulting in difficulty in estimating L value 0 Lack of information on how to measure the surface diffusion of CH 4 resulting in difficulty in estimating k value 7

8 Methane Generation Kinetics Methane Generation Kinetic Equation dm dt CH 4 = k L0 M sw Tier 2 Q CH = L 0 Mt {exp( kc) exp( kt)} 4 Revised Tier 2 Q CH N [ exp{ k( t i) } exp{ k( t i 1) }] ( t) = 0( ) 0( ) + 4 M i L i i= 1 Key Parameters for Tier 2 Methodology L 0 (Methane Generation Potential) L 0 = MCF x DOC x DOC F x F x 16/12 MCF: 0.4~1.0 DOC: Country Specific Equation DOC(%) = x FW x PA x WO x RU x SL x AN x OT DOC F : 0.5~0.6 F: 0.4~0.6 8

9 Key Parameters for Tier 2 Methodology k (Methane Generation Constant) (1) First Methodology k = β + β 2 4αγ 2α where 2 2 c t QCH 4 α =, β = t c, γ = 2 L M 0 t (2) Second Methodology Best fit to generation rate of CH 4 at a certain year Surface Diffusion Measurements Digital Thermometer Sampling Port 19cm Floating Tube 48cm 9

10 Fortran Code for Estimating k value Fortran Output TCE 경과연수 (year) 0 0

11 L 0 and K values for Korean Landfills L 0 : 0.15~0.30 ton-ch 4 /ton-waste k : 0.04~0.09 yr -1 IPCC default value : 0.05 yr -1 Comparison of CH 4 emission from a Korean Landfill between Tier 1 and Tier 2 30, , , TCE(ton/yr) 15,000 TCE(ton/yr) , , Year Year Tier 1 Tier 2 1

12 Estimation procedures for CH 4 emission by the Tier 2 Classification of landfills by characteristics Estimation of k values for characteristic landfills Estimation of CH 4 emissions form individual landfills Summation of CH 4 emission from individual landfills Considerations on changing emission methodology from Tier 1 to Tier 2 Pre-requisitesrequisites Collecting information on landfill histories of all landfills: landfill amount, compositions of solid wastes, and landfill period etc. Monitoring the seasonal emission rates of CH 4 from the surfaces of representative landfills Predicted Problems Uncertainty arising from the assumption of the landfill histories of non-sanitary landfills Difficulty in data managements: QA/QC and UA 2

13 Thank you very much! 3