Evaluation of dual permeability of gas flow in municipal solid waste: Extraction well operation

Abstract

The dual permeability model (DPM) is used to describe the gas flow in landfills under the preferential flow effect. A steady‐state radial DPM was developed in this study to predict gas distribution at extraction well operations. Two typical cases of a short‐term pumping field test from a single extraction well were also studied. The sensitivity of kf/km and mass transfer coefficient in the DPM was simulated. The mechanism of higher deviation between the simulation result and the test could be explained by the gas flux and influence radius, as determined by the single permeability model based on gas pressure distribution in the radial direction. The reliability of the DPM in the prediction of gas flux and influence radius in extraction wells was initially verified. The study provides evidence of the improvement of the design and operation parameters of extraction wells in landfills using the proposed method. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1381–1386, 2016