A multi-scale model for CO2 sequestration enhanced coalbed methane recovery
A multi-scale model for CO2 sequestration enhanced coalbed methane recovery
G. X. WANG1(), X. R. WEI1, V. RUDOLPH1, C. T. WEI2, Y. QIN2
1. School of Engineering, University of Queensland, St Lucia Qld 4072, Australia; 2. School of Resources and Geoscience, China University of Mining & Technology, Xuzhou221008, China
This paper presents a multi-scale model to simulate the multicomponent gas diffusion and flow in bulk coals for CO2 sequestration enhanced coalbed methane recovery. The model is developed based on a bi-dispersed structure model by assuming that coal consists of microporous micro-particles, meso/macro-pores and open microfractures. The bi-disperse diffusion theory and the Maxwell-Stefan approach were incorporated in the model, providing an improved simulation of the CH4—CO2/CH4—N2 counter diffusion dynamics. In the model, the counter diffusion process is numerically coupled with the flow of the mixture gases occurring within macro-pores or fractures in coal so as to account for the interaction between diffusion and flow in gas transport through coals. The model was validated by both experimental data from literature and our CO2 flush tests, and shows an excellent agreement with the experiments. The results reveal that the gas diffusivities, in particular the micro-pore diffusivities are strongly concentration-dependent.
Corresponding Author(s):
WANG G. X.,Email:gxwang@uq.edu.au
引用本文:
. A multi-scale model for CO2 sequestration enhanced coalbed methane recovery[J]. Frontiers of Chemical Engineering in China, 2009, 3(1): 20-25.
G. X. WANG, X. R. WEI, V. RUDOLPH, C. T. WEI, Y. QIN. A multi-scale model for CO2 sequestration enhanced coalbed methane recovery. Front Chem Eng Chin, 2009, 3(1): 20-25.
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