Title:
PULSE DETONATION CRACKING AND PERMEABILITY-INCREASING METHOD FOR COAL-BED GAS WELL
Document Type and Number:
WIPO Patent Application WO/2018/076492
Kind Code:
A1
Abstract:
Disclosed is a pulse detonation cracking and permeability-increasing method for a coal-bed gas well, applied to coal-bed gas well mining for a coal bed (1) with a low gas permeability. In the method, first, a positive-electrode coal-bed gas well bore (2) and a negative-electrode coal-bed gas well bore (3) are constructed from the ground to the coal bed (1). A fixed platform (4) having a positive electrode (5) installed thereon and a high voltage pulse device (7) are placed downwardly to a coal-bed pre-permeable portion in the positive-electrode coal-bed gas well bore (2) by means of a derrick (11), and another fixed platform (4) having a negative electrode (6) installed thereon is placed downwardly to a coal-bed pre-permeable portion in the negative-electrode coal-bed gas well bore (3) by means of the derrick (11). Next, the coal bed (1) between the positive electrode (5) and the negative electrode (6) is broke down with a high voltage to extract coal bed gas from the positive-electrode coal-bed gas well bore (2) and the negative-electrode coal-bed gas well bore (3). The high energy generated by a high-voltage electrical pulse directly acts on the coal bed (1) and forms a plasma channel in the coal bed (1) between the positive electrode (5) and the negative electrode (6). Huge energy passes though the plasma channel instantly, and a high temperature thermal expansive force and a shock wave formed act on the coal bed (1), effectively increasing the number of cracks in the coal bed (1) and creating a good condition for gas flow in the coal bed (1).
Inventors:
LIN BOQUAN (CN)
YAN FAZHI (CN)
ZHANG XIANGLIANG (CN)
KONG JIA (CN)
LIU TING (CN)
ZHU CHUANJIE (CN)
YAN FAZHI (CN)
ZHANG XIANGLIANG (CN)
KONG JIA (CN)
LIU TING (CN)
ZHU CHUANJIE (CN)
Application Number:
PCT/CN2016/110047
Publication Date:
May 03, 2018
Filing Date:
December 15, 2016
Export Citation:
Assignee:
UNIV CHINA MINING (CN)
International Classes:
E21F7/00; E21B43/26
Foreign References:
| CN104863561A | 2015-08-26 | |||
| CN104832149A | 2015-08-12 | |||
| CN104863628A | 2015-08-26 | |||
| CN104453827A | 2015-03-25 | |||
| US4084638A | 1978-04-18 |
Attorney, Agent or Firm:
NANJING RUI HONG PATENT AND TRADEMARK OFFICE LLP (CN)
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