Study on mechanical properties test of coal rock and fracturing stimulation methods
The CBM reservoir in China has the characteristics of complex geological structure,low permeability and strong adsorption ability,etc.These problems present challenges to the exploitation of coalbed methane.The tests of density,sound,uniaxial compressive strength are carried out to obtain the physical and mechanical property parameters of coal rock samples of Qinshui basin.At the same time,stress sensitivity experiments are taken by the permeability testing device.Moreover,the effects of confining pressure on permeability of coal rock are studied.The numerical simulation model of fracturing on CBM reservoir is built up based on the experimental results and formation distribution conditions.Moreover,the influence factors on hydraulic fracturing are studied.The experimental results show that: different coal samples have different densities and acoustic time,and the differences of Poisson ratio,elastic and volume modulus between samples are great.There is proportionality between uniaxial compressive strength and elastic modulus of coal rock.Based on the same displacement pressure,the permeability of coal rock decreases with increasing confining pressure,meanwhile,the damage rate of coal samples is higher.The pseudo-3D model of 2D flow has a perfect performance in analyzing the fracture development during hydraulic fracturing in coal seam.The crack width decreases with increasing elastic modulus,and the crack developments towards the height direction.Based on the same crack length,fracture height will increase with the pump injection flow increasing.
coal seam mechanical parameters stress sensitivity hydraulic fracturing numerical simulation
Tingting Jiang Xiujuan Yang Xiangzhen Yan
College of pipeline and civil engineering China University of Petroleum Qingdao,China
国际会议
西安
英文
1-5
2012-10-01（万方平台首次上网日期，不代表论文的发表时间）