CGE hands-on training workshop on GHG inventories Jan 8-12 Environmental Management Corp. Republic of Korea Dr. Kyoung-sik Choi

Objectives Test and analysis for Tier 1 method Feasibility study of Tier 2 Method CH4 Emission Coefficient constant by characteristics of landfill - Landfill Condition – –Climate Comparison between Tier 1 and Tier 2 Developing of reliable emission method by Tier 2 method

Apply IPCC Default value Underestimate Emission IPCC Method Measurement of Emission Reliability Problems Measurement & Development of Reliability Developing Status IPCC Good Practice How? [Initial Status] [MOE Proposal] Developing status

Emission Patterns in Landfill Extraction Well Surface Diffusion Time Emission Rate Crack or Weak Point A B CH4 Emission rate in landfill vs Time

IPCC Good Practice Guidance Default Method : Tier 1 AssumptionAssumption –MSW landfilled in a year would be converted completely into CH 4 which would be emitted from the landfill in the same year Limitation to applicationLimitation to application –Only applicable for landfills demonstrating constant quality and quantity of MSW with respect to time

Default MethodDefault Method CH 4 = (MSW T x MSW F x L 0 –R) x (1-OX) MSW T = Total MSW generated (Gg/yr) MSW F = Fraction of MSW disposed at Landfills L 0 = Methane generation potential (Gg CH 4 /Gg waste) L 0 = MCF ⅹ DOC ⅹ DOC F ⅹ F ⅹ 16/12 MCF = Methane Correction Factor (fraction) DOC = Degradable organic carbon (fraction) DOC F = Fraction DOC dissimilated F = Fraction by volume of CH 4 in landfill gas R = Recovered CH 4 (Gg/year) OX = Oxidation factor (fraction)

Tier 2 : FOD MethodTier 2 : FOD Method Assumption Assumption Assumption total landfill sites as a similar type landfillAssumption total landfill sites as a similar type landfill Annual waste amount is a certain level during landfill periodsAnnual waste amount is a certain level during landfill periods Application Application To record disposal activity data in the landfillTo record disposal activity data in the landfill Q CH4 (CH 4 Emission : ton/yr) = k × L 0 × M 0 M CH4 ( CH 4 Emission : ton) =M 0 × L 0 × {exp(-kc)-exp(-kt)}

Questions GHG emission calculation correct?GHG emission calculation correct? Degree of the exact data necessary?Degree of the exact data necessary? Different from existing research?Different from existing research?

Decision Tree Are waste disposal activity data obtainable for the current inventory year? YES Are waste disposal activity data available for previous years? Estimate CH4 emissions using the First Order Decay (FOD) method YES Use IPCC default values, per capita or other methods to estimate activity data Estimate CH 4 emissions using the IPCC default method NO Is this a key source category (Note 1)? NO Obtain or estimate data on historical changes in solid waste disposal YES NO

Selection of Emission Method Tier 1 available data for disposal activity in the landfill?  Key parameter for Tier 1 Method (1) Total MSW (2) DOC (3) DOC F (4) MCF (5) R (6) OX CH 4 Emission(ton/yr) = (MSW T x MSW F x MCF x DOC x DOC F x F x 16/12 – R) x (1-OX)

Credibility diagnosis of variable on landfill area Landfill quantity(MSW T x MSW F )Landfill quantity(MSW T x MSW F ) –National statistics data “national waste generation and treatment status” DOC(organic carbon)DOC(organic carbon) –Carbon content of organic waste  96 national waste statistics investigation, developed nations data –Development of estimation equation for domestic conditions DOC(%) = x FW x PA x WO x RU x SL x AN x OT Uncertainty and possibility of error Accuracy of carbon content according to waste characteristic Use of existing document data

DOC F (fraction DOC dissimilated)DOC F (fraction DOC dissimilated) –IPCC Good Practice basic value : 0.5~0.6 Average value : 0.55 selectionAverage value : 0.55 selection –Comparison of domestic and international data Dong-a Construction(1997) : domestic waste -> 0.596Dong-a Construction(1997) : domestic waste -> USA EPA : domestic waste -> 0.584USA EPA : domestic waste -> Uncertainty and possibility of error DOC F data on sludge, animal and plant waste and other combustibes Use of existing document data Decide by basic experiment

MCF(Methane correction factor)MCF(Methane correction factor) –IPCC basic value Sanitary landfill : 1.0Sanitary landfill : 1.0 Non-sanitary landfill : 0.4~0.8Non-sanitary landfill : 0.4~0.8 –Select 1.0 by MCF Foundation : present landfill in progress is sanitary landfillFoundation : present landfill in progress is sanitary landfill Uncertainty and possibility of error Non-sanitary landfill that has finished landfill Investigation of non-sanitarylandfill ’ s role in the perspective of generation quantity

R(recovery ratio of CH4)R(recovery ratio of CH4)  Status of landfill LFG recovery use Uncertainty and possibility of error In cases of flaring, exact estimation of CH4 oxidation quantity is difficult Difficult to ensure national statistics data  Necessity of systematic data collection  OX(oxidation factor)  Sanitary landfill : 0.1  Select 0.1 by regarding domestic landfill as sanitary landfill Uncertainty and possibility of error Difficult to estimate exact OX on-site

Variable value decided at current research studies variable IPCC USA MOE Current Research (2000) (2000) MCF 0.6~ DOC(%) estimation equation 18~ development of indigenous equation DOC F 0.5~ F R(%) each landfill each landfill OX 0.0~

Estimation equation of CH4 generation quantity CH 4 total emission quantity(ton/yr) = x DOC x MSW L CH 4 original emission quantity(ton/yr) = x DOC x MSW L IPCC : 712,619 ton CH 4 MOE(2000) : 987,384 ton CH 4 Current research result : 637,934 ton CH 4

Change of landfill GHG estimation equation Tier 1 Tier 2 PreconditionPrecondition –Investigation on landfill record of national landfill site Investigation item : landfill quantity, landfill waste, landfill periodInvestigation item : landfill quantity, landfill waste, landfill period Expected problemsExpected problems –Estimation of disposal activity data on non- sanitary landfill –Insufficient investigation on plant waste landfill

Flow diagram of CH4 generation quantity of domestic landfill by Tier 2 Classify national landfill according to landfill characteristic Decide CH4 generation rate constant according to landfill characteristic Decide landfill quantity, landfill year and CH4 generation rate constant In cases of regarding national landfill as singular landfill Estimation of CH4 generation quantity of specific year

Decision Method of for CH4 emission CH4 generation dynamic equation Developed Method IPCC Method

Developed Fortran Codes

Ulsan Sung-am landfill

Decision of main variable of Tier 2 : CH4 emission factor and CH4 generation rate constant Landfill CH4 emission factor(L 0 ) CH4 emission factor(L 0 )(ton-TCE/ton-Waste) CH4 emission velocity constant (k : yr -1 ) (k : yr -1 ) Note 1 time 2 times Average 1 time 2 times Average Ulsan city, Sung-am Dong Kyong-gi province, Yong-in city Choong-nam province, Bo- ryung city Choong-book province, Jae- chun city Insufficient landfill record data Choong-nam province, Chun-an city

CH4 emission quantity for each landfill by Tier 1 Landfill Landfill quantity and average during investigation period Total GHG emission quantity during investigation period(TCE) Average GHG emission quantity during investigation period(TCE) GHG emission quantity for year 2001(TCE) Ulsan city, Sung-am Dong 1,605,966ton(6 years) Average : 267,661 ton 489,578 ton 81,597 ton 40,574 ton Kyong-gi province, Yong- in city 308,628 ton(6 years) Average : 51,438 ton 96,167 ton 16,028 ton 10,578 ton Choong-nam province, Bo- ryung city 73,073 ton(3 years) Average : 24,358 ton 6,343 ton 2,114 ton 1,942 ton Choong-book province, Jae- chun city 147,167 ton(4 years) Average : 36,792 ton 13,055 ton 3,264 ton 3,292 ton Choong-nam province, Chun- an city 336, 404 ton(6 years) Average : 56,067 ton 90,191 ton 15,032 ton 7,296 ton

Comparison between Tier 1 & Tier 2 method Results (Yongin Landfill) Tier 1 Result Tier 2 Result

Conclusion Introduction and development of improved CH4 estimation equation and finalization of CH4 generation rate constant decision methodIntroduction and development of improved CH4 estimation equation and finalization of CH4 generation rate constant decision method –IPCC applies yearly average landfill quantity In cases of severe changes in yearly landfill quantity, credibility of emission estimation results decreaseIn cases of severe changes in yearly landfill quantity, credibility of emission estimation results decrease CH4 emission quantity estimated during landfill had Tier 1 with results much higher than Tier 2 resultsCH4 emission quantity estimated during landfill had Tier 1 with results much higher than Tier 2 results –Due to the hypothesis that Tier 1 emits landfill waste at the same time as it is landfilled

Precondition to estimate Tier 2Precondition to estimate Tier 2 –Collection of landfill record information –Classification according to national landfill characteristics Landfill waste, landfill method, landfill period and date, landfill quantity, climateLandfill waste, landfill method, landfill period and date, landfill quantity, climate It is assumed that CH4 emission estimation by Tier 2 is possible within 1~2 years in the near futureIt is assumed that CH4 emission estimation by Tier 2 is possible within 1~2 years in the near future Unsatisfactory management of statistics data on landfill quantity and characteristicsUnsatisfactory management of statistics data on landfill quantity and characteristics –Due to inconsistency, data follow-up and CH4 emission quantity estimation is difficult –Necessary to develop guide on landfill waste management