收稿日期: 2014-05-20
修回日期: 2014-07-29
网络出版日期: 2015-01-10
基金资助
国家科技重大专项课题(编号:2011ZX05034-00;2011ZX05042-03);河南理工大学杰出青年基金项目(编号:J2013-03)联合资助.
The Changing Laws of Dynamic Water Porosity about the Coal Reservoir in Single Phase Flow Stage
Received date: 2014-05-20
Revised date: 2014-07-29
Online published: 2015-01-10
查明煤层气井排采过程中动水孔隙度的变化规律能为产水量准确预测、排采工作制度合理制定提供依据。借助复变函数理论和弹塑性力学理论，构建了原始状态不同裂隙展布下储层应力分布的数理模型|结合损伤理论、有效应力原理以及结构变形理论，构建了排采过程中应力与结构的损伤动态演化模型|基于水运移平衡条件以及储层孔裂隙展布规律，耦合应力、结构变形损伤作用，构建了单相水流阶段动水孔隙度的数理模型。以沁水盆地樊庄区块为例，计算得出:当裂隙宽度为0.1μm左右时，裂隙周围应力、结构损伤加剧，相关研究佐证了这一结论。随着排采的进行，储层压力的降低，动水孔隙度呈指数形式减小并最终趋于稳定。随孔隙度的增大呈线性增大|随尺寸较小的裂隙比例增大呈线性降低。
张崇崇，王延斌，倪小明，王向浩 . 单相水流阶段煤储层动水孔隙度变化规律[J]. 天然气地球科学, 2015 , 26(1) : 154 -159 . DOI: 10.11764/j.issn.1672-1926.2015.01.0154
Finding out the changing laws of dynamic water porosity can provide the theory base for predicting the water production and making drainage working flow in drainage stage of coal bed methane wells.According to the theory of complex variable functions,elastic and plastic mechanics,the mathematical model about reservoir fracture stress distribution was established in original state under different fracture distribution.According to the damage theory,principle of effective stress,and the structural deformation theory,the stress and damage evolution model was established during the dynamic changes of production process.According to water migration equilibrium conditions and the pore and fracture distribution,coupled with the effect of the stress and deformation of the structure,the mathematical model of dynamic water porosity was established.Taking Fanzhuang block of Qinshui Basin as a calculating example,the results show that:the critical width of the crack is 0.1μm according to the changing values of the stress and structural damage,and it can be testified by related research results.The reservoir water porosity is reduced exponentially and tends to be stable finally in the drainage process.It increases linearly with the increase of porosity,reduces linearly with the increase in smaller crack ratio.
Key words： Single phase flow; Dynamic water porosity; Fissured structure; Damage; Deform
［1］Ni Xiaoming,Wang Yanbin,Jie Mingxun,et al.Reasonable production intensity of coal bed methane wells in initial production[J].Journal of Southwest Petroleum University,2007,29(6):101-105.［倪小明,王延斌,接铭训,等.煤层气井排采初期合理排采强度的确定方法[J].西南石油大学学报,2007,29(6):101-105.］
［2］George R.Coates,Lizhi Xiao.NMR Logging Principles & Applications［M］.Texas:Gulf Publishing Company,1999.
［3］Yao Yanbin,Liu Dameng.Comparison of low-field NMR and mercury intrusion porosimetry in characterizing pore size distributions of coals[J].Fuel,2012,95(5):152-158.
［4］Zhao Yi,Hu Bin,Zhang Luqi,et al.Calculation of reservoir irreducible water saturation based on NMR experiment and mercury penetration experiment[J].Science and Technology Review,2010,28(11):64-68.［赵毅,胡斌,张路崎,等.基于核磁共振和压汞实验的储层束缚水饱和度计算方法[J].科技导报,2010,28(11):64-68.］
［5］Xian Deqing,Fu Shaoqing,Xie Ranhong.Study on NMR logging bulk volume of irreducible water model[J].Nuclear Electronics & Detection Technology,2007,27(3):578-582.［鲜德清,傅少庆,谢然红.核磁共振测井束缚水模型研究[J].核电子学与探测技术,2007,27(3):578-582.］
［6］Wang Xiaochang,Fan Yiren,Deng Shaogui,et al.Irreducible water saturation determ ination based on centrifugal test data[J].Journal of China University of Petroleum,2009,33(3):76-80.［王晓畅,范宜仁,邓少贵,等.基于离心试验数据确定束缚水饱和度[J].中国石油大学学报:自然科学版,2009,33(3):76-80.］
［7］Gao Shusheng,Ye Liyou,Xiong Wei,et al.Nuclear magnetic resonance measurements of original water saturation and mobile water saturation in low permeability sandstone gas[J].Chinese Physics Letters,2010,27(2):1-2.
［8］Cheng Yuanfang,Shen Haichao,Zhao Yizhong,et al.Study on fluid-solid coupling of physical variation of gas hydrate reservoirs during natural gas development[J].Acta petrolei Sinica,2010,31(4):607-612.［程远方,沈海超,赵益忠,等.天然气水合物藏开采物性变化的流固耦合研究[J].石油学报,2010,31(4):607-612.］
［9］Lu Baoping,Xu Zenghe.Mathematical model for fluid-solid coupling near well bore in elastic-plastic oil reservoir[J].Acta Petrolei Sinica,2006,27(5):131-134.［路保平,徐曾和.井眼周围可变形储层流—固耦合数学模型[J].石油学报,2006,27(5):131-134.］
［10］Fu Xuehai,Qin Yong,Wei Chongtao,et al.An analysis of fluid effect during coalbed methane drainage in the well QNDN1[J].Natural Gas Industry,2010,30(6):48-51.［傅雪海,秦勇,韦重韬,等.QNDN1井煤层气排采的流体效应分析[J].天然气工业,2010,30(6):48-51.］
［11］Zhang Guangming,Liu He,Zhang Jin,et al.Mathematical model and nonlinear finite element equationfor reservoir fluid-solid coupling[J].Rock and Soil Mechanics,2010,31(5):1657-1663.［张广明,刘合,张劲,等.储层流固耦合的数学模型和非线性有限元方程[J].岩土力学,2010,31(5):1657-1663.］
［12］Yang Manping,Li Yun,Peng Caizhen.Analysis of stress sensitivity for irreducible water of gas reservoir[J].Natural Gas Geoscience,2004,15(4):391-395.［杨满平,李允,彭彩珍.气藏储层含束缚水的应力敏感性分析[J].天然气地球科学,2004,15(4):391-395.］
［13］Fu Xuehai,Qin Yong.Coalbed Methane Geology［M］.Xuzhou:China University of Mining and Technology Press,2007:34-41.［傅雪海,秦勇.煤层气地质学［M］.徐州:中国矿业大学出版社,2007:34-41.］
［14］Liu Yourong,Tang Huiming.Rock Mechanics［M］.Wuhan:China University of Geosciences Press,1999:60-68.［刘佑荣,唐辉明.岩体力学［M］.武汉:中国地质大学出版社,1999:60-68.］
［15］Ni Xiaoming,Zhagn Chongchong,Wang Yanbin,et al.The change law about the coal matrix shrinkage during water-gas flow stages[J].Natural Gas Geoscience,2013,24(5):1069-1074.［倪小明,张崇崇,王延斌,等.气、水两相流阶段煤基质收缩变化规律研究[J].天然气地球科学,2013,24(5):1069-1074.］
［16］Terzaghi K.Die Berechnung der Durchlaeassigkeitsziffer desTones AuS dem Verlauf der Hydrodynamoschen Spannun-gserscheinungen,Sitzungsber[J].Sitzungsber Akad Wiss Wien Math Natur Wisslln,1923,132:125-138.
［17］Gao Yanfa,Zhang Jinsong.Mines Rockmass Mechanics［M］.Xuzhou:China University of Mining and Technology Press,2000:36-40.［高延法,张劲松.矿山岩体力学［M］.徐州:中国矿业大学出版社,2000:36-40.］
［18］Yao YanBin,Liu Dameng,Cai Yidong,et al.Advanced characterization of pores and fractures in coals by nuclear magnetic resonance and X-ray computed tomography[J].Science China:Earth Sciences,2010,53(11):854-862.
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