Dynamic Variation Character of CBM Reservoir Permeability during Depletion of High-Rank Coalbed Methane

Abstract:

Article Preview

China is rich in CBM resources, but so far, some production wells present low production and rapid decline trend. In addition to these objective factors such as low permeability and complexity of geological structure of CBM reservoir, there is still the most important problem during the exploitation techniques that is the lack of understanding to dynamic variation character of CBM reservoir permeability, which leads to the unreasonable work of depletion for coalbed methane.Using P&M model and parameters from 3# coal seam of Shanxi Formation, Permian system in Qinshui basin, the permeability variations of this block (first decline, then ascend, reaching 2.8 times of initial permeability at the end) were analyzed, revealing good depletion prospect of this CBM field, and pointed that the higher Young's modulus is, the more obvious matrix shrinkage is and the higher gas saturation is, the more favor for permeability improvement through sensitivity analysis. Finally, two suggestions were proposed, (1) add the 'permeability variations' to the parameters for CBM block select, which may find the "innate" in the late development of the poor condition of properties easy to improve, develop potential for larger blocks. (2) Adjust and optimize the depletion method (amplitude and frequency of bleeding, pressure reduction) according to the permeability variation characters discussed in this paper

Info:

Periodical:

Advanced Materials Research (Volumes 233-235)

Edited by:

Zhong Cao, Lixian Sun, Xueqiang Cao, Yinghe He

Pages:

2267-2271

DOI:

10.4028/www.scientific.net/AMR.233-235.2267

Citation:

G. Z. Li et al., "Dynamic Variation Character of CBM Reservoir Permeability during Depletion of High-Rank Coalbed Methane", Advanced Materials Research, Vols. 233-235, pp. 2267-2271, 2011

Online since:

May 2011

Export:

Price:

$35.00

In order to see related information, you need to Login.

In order to see related information, you need to Login.