3상 거동 상대투수율 선정에 따른 불포화대 및 포화대 내NAPL 거동 특성 연구

Abstract

Differences in subsurface migration of LNAPL/DNAPL contaminants caused by a selection of 3-phase (aqueous, NAPL,and gas) relative permeability function (RPF) models in numerical modeling were investigated. Several types of RPFmodels developed from both experimental and theoretical backgrounds were introduced prior to conducting numericalmodeling. Among the RPF models, two representative models (Stone I and Parker model) were employed to simulatesubsurface LNAPLs/DNAPLs migration through numerical calculation. For each model, the spatiotemporal distribution ofindividual phases and the mole fractions of 6 NAPL components (4 LNAPL and 2 DNAPL components) were calculatedthrough a multi-phase and multi-component numerical simulator. The simulation results indicated that both spilledLNAPLs and DNAPLs in the unsaturated zone migrated faster and reached the groundwater table sooner for Stone Imodel than Parker model while LNAPLs migrated faster on the groundwater table under Parker model. This resultssignified the crucial effect of 3-phase relative permeability on the prediction of NAPL contamination and suggested thatRPF models should be carefully selected based on adequate verification processes for proper implementation of numericalmodels.