Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal

The coal-bed methane (CBM) resources in soft and low-permeability coals are assumed to be as much as 15 × 1012 m3 in China. Indirect fracturing technology can be an effective method to successfully extract methane within soft coals. The key to the success of this technique is to optimize the paramet...

Full description

Saved in:
Bibliographic Details
Main Authors: Wenfeng Yuan, Xigui Zheng, Niaz Muhammad Shahani
Format: Article
Language:English
Published: Wiley 2022-01-01
Series:Geofluids
Online Access:http://dx.doi.org/10.1155/2022/7436051
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832564472905990144
author Wenfeng Yuan
Xigui Zheng
Niaz Muhammad Shahani
author_facet Wenfeng Yuan
Xigui Zheng
Niaz Muhammad Shahani
author_sort Wenfeng Yuan
collection DOAJ
description The coal-bed methane (CBM) resources in soft and low-permeability coals are assumed to be as much as 15 × 1012 m3 in China. Indirect fracturing technology can be an effective method to successfully extract methane within soft coals. The key to the success of this technique is to optimize the parameters, such as water injection flow rate and fracture initiation location, so that the hydraulic fracturing parameters enable the fractures to pass through the interface between coal and rock and propagate sufficiently into the coal. This paper focuses on solving the above problems by focusing on discontinuities and plastic characteristics of soft coals. Voronoi polyhedron was used to simulate the discontinuities of coal, and the constitutive relations of ductile fracture-seepage and elastoplastic damage-seepage are, respectively, given to the discontinuities and coal matrix. A numerical model was established based on the above theory to simulate the effect of stress difference Δσ, coal-rock interface friction coefficient fc,r, water injection flow rate iw, and distance between the well and the interface Dop on indirect fracturing fractures. The results show that the HFs area in the coal is positively correlated with Δσ, fc,r, and iw, and it first increases and then decreases with the decrease of Dop. The above results were applied in the Zhaozhuang mine of Qinshui Basin by optimizing Dop = 1 m and iw = 8 m3/min, so that CBM production has been greatly increased. The results can provide theoretical support for the efficient development of CBM in fractured and low-permeability coal seam areas.
format Article
id doaj-art-5a2799283c994506b0b8da77768e7e5e
institution Kabale University
issn 1468-8123
language English
publishDate 2022-01-01
publisher Wiley
record_format Article
series Geofluids
spelling doaj-art-5a2799283c994506b0b8da77768e7e5e2025-02-03T01:10:58ZengWileyGeofluids1468-81232022-01-01202210.1155/2022/7436051Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability CoalWenfeng Yuan0Xigui Zheng1Niaz Muhammad Shahani2School of MinesSchool of MinesSchool of MinesThe coal-bed methane (CBM) resources in soft and low-permeability coals are assumed to be as much as 15 × 1012 m3 in China. Indirect fracturing technology can be an effective method to successfully extract methane within soft coals. The key to the success of this technique is to optimize the parameters, such as water injection flow rate and fracture initiation location, so that the hydraulic fracturing parameters enable the fractures to pass through the interface between coal and rock and propagate sufficiently into the coal. This paper focuses on solving the above problems by focusing on discontinuities and plastic characteristics of soft coals. Voronoi polyhedron was used to simulate the discontinuities of coal, and the constitutive relations of ductile fracture-seepage and elastoplastic damage-seepage are, respectively, given to the discontinuities and coal matrix. A numerical model was established based on the above theory to simulate the effect of stress difference Δσ, coal-rock interface friction coefficient fc,r, water injection flow rate iw, and distance between the well and the interface Dop on indirect fracturing fractures. The results show that the HFs area in the coal is positively correlated with Δσ, fc,r, and iw, and it first increases and then decreases with the decrease of Dop. The above results were applied in the Zhaozhuang mine of Qinshui Basin by optimizing Dop = 1 m and iw = 8 m3/min, so that CBM production has been greatly increased. The results can provide theoretical support for the efficient development of CBM in fractured and low-permeability coal seam areas.http://dx.doi.org/10.1155/2022/7436051
spellingShingle Wenfeng Yuan
Xigui Zheng
Niaz Muhammad Shahani
Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal
Geofluids
title Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal
title_full Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal
title_fullStr Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal
title_full_unstemmed Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal
title_short Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal
title_sort optimization of indirect fracturing process parameters based on mechanical properties of fractured and low permeability coal
url http://dx.doi.org/10.1155/2022/7436051
work_keys_str_mv AT wenfengyuan optimizationofindirectfracturingprocessparametersbasedonmechanicalpropertiesoffracturedandlowpermeabilitycoal
AT xiguizheng optimizationofindirectfracturingprocessparametersbasedonmechanicalpropertiesoffracturedandlowpermeabilitycoal
AT niazmuhammadshahani optimizationofindirectfracturingprocessparametersbasedonmechanicalpropertiesoffracturedandlowpermeabilitycoal