Open AccessFinite element analysis of damage region of CBM well based on underbalance reconstruction technology
Author(s) -
Xitao Bao,
Jianhua Yang,
Yifei Yan,
Xiangzhen Yan
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/729/1/012026
Subject(s) - coalbed methane , coal , petroleum engineering , permeability (electromagnetism) , methane , porosity , finite element method , geology , coal mining , environmental science , materials science , geotechnical engineering , engineering , structural engineering , waste management , chemistry , biochemistry , organic chemistry , membrane
The reserves of coalbed methane (CBM) in China are very high. But the characteristics of “three low” (low pressure, low permeability, low porosity), thin formation and shallow burial depth for the CBM reservoirs may cause problems of long production cycle and slow increase in production. For above problems, a new reconstruction method for coal bed methane formation named underbalance reconstruction was introduced. By this method, a jet generator was lowered to perforated interval. Then, with the nitrogen injected and blowout, reconstruction results of coalbed reservoir can be achieved. Considered the process of underbalance reconstruction, coalbed reservoir properties and mechanical properties of coalbed, mechanical model of coalbed methane well was built and analyzed by finite element method. Afterwards, damage area of different nitrogen injecting cycle can be characterized. And the effect of underbalance reconstruction for coal bed methane formation can be obtained. Then, parameters of reconstruction technology can be optimized and optimization scheme can be supplied for the underbalance reconstruction for coal bed methane formation.