页岩气藏“井工厂”模式下水平井裂缝分布优化

摘要/Abstract

摘要：

与常规气藏单井开发模式相比,“井工厂”开发技术具有大幅提高作业效率、降低工程成本等优点。页岩气藏“井工厂”小井距布井以及体积压裂模式下存在井间干扰和缝间干扰,影响井组整体开发效果。基于非结构PEBI网格技术自主研发了压裂水平井PEBI网格模拟器,并以微地震监测结果为依据,将水平井组体积压裂形成增产改造体积区（SRV）（考虑为椭圆形）,综合考虑了页岩气吸附解吸、扩散和非线性渗流机制,采用控制体有限单元法建立了均质页岩气藏“井工厂”模式定压生产条件下压裂水平井组数值模拟模型,计算对比了单井生产和井组生产累计产量的差异,讨论了均质页岩气藏井组不同压裂裂缝分布方式和水平井布井方式对井组累计产量的影响。研究结果表明：小井距布井产生的井间渗流干扰使得井组产量低于单井产量叠加之和;单井U型布缝模式能一定程度上减少干扰,使得其井组累计产量要优于均匀和反U型布缝模式;水平井交叉布井下累计产量要优于平行布井。

关键词: 页岩气, 井工厂, 压裂水平井, 产量, 优化

Abstract:

Compared with the single well development mode of the conventional gas reservoirs, multi-well pad technology has several advantages such as great improvement of operating efficiency and reduction of project cost. Strong interference between the wells and between the fractures exist in small well spacing and network fracturing mode of multi-well pad for shale reservoir, which affect the overall development effect of the well group. Based on the unstructured PEBI grid technology, its simulator for fracturing horizontal wells is developed independently. According to the results of microseismic monitoring, the stimulated reservoir volume（SRV） area formed by the network fracturing of horizontal well groups are assumed to be ovals. Considering the adsorption, desorption, diffusion and nonlinear seepage mechanisms of shale gas, the numerical simulation model of the fracturing horizontal well group in the multi-well pad mode is established by the finite element method. The difference between the cumulative production of the single well and the well group is compared, and the influence of the layout mode of the fractures and the horizontal wells on the cumulative production in homogeneous shale gas reservoirs are discussed. The results show that the inter-well seepage interference makes the cumulative production of the well group lower than the sum of that of a single well. U-shape layout mode of the fractures for single well can reduce the interference to a certain extent, which make the cumulative production of the well group superior to that of the uniform mode and the inverted U-shape mode. The cumulative production of cross distribution of horizontal wells is better than that of parallel mode.

Key words: shale gas, multi-well pad, fractured horizontal well, production, optimization

中图分类号:

TE37

段永刚,张泰来,魏明强等. 页岩气藏“井工厂”模式下水平井裂缝分布优化[J]. 油气藏评价与开发, 2019, 9(6): 78-84.

Yonggang DUAN,Tailai ZHANG,Mingqiang WEI, et al. Optimization of fracture layout of fractured horizontal well in multi-well pad mode of shale gas reservoirs[J]. Reservoir Evaluation and Development, 2019, 9(6): 78-84.

图/表 8

图1

图2

图3

表1

图4

图5

图6

图7

参考文献 20

[1]	查树贵, 刘利平, 廖朋 , 等. 水平井地震地质导向技术及其在涪陵页岩气田的应用[J]. 石油物探, 2018,57(3):369-377 .
[2]	王敏生, 光新军 . 页岩气“井工厂”开发关键技术[J]. 钻采工艺, 2013,36(5):1-4.
[3]	邹才能, 董大忠, 王玉满 , 等. 中国页岩气特征、挑战及前景(二)[J]. 石油勘探与开发, 2016,43(2):166-178.
[4]	叶飞 . “工厂化”作业模式在威远页岩气开发中的应用探讨[J].石化技术, 2017(4):239-240.
[5]	赵国英 . 水平井“工厂化”部署与设计优化——以四川威远页岩气藏为例[J]. 天然气勘探与开发, 2018,41(1):51-57.
[6]	李彬, 付建红, 秦富兵 , 等. 威远区块页岩气“井工厂”钻井技术[J].石油钻探技术, 2017(5):18-23.
[7]	冯福平, 雷扬, 陈顶峰 , 等. 基于有限元数值模拟的致密储层体积压裂效果影响参数分析[J].油气藏评价与开发, 2019(1):29-33.
[8]	刘欣, 张莉娜, 张耀祖 . 川东南页岩气井压裂参数对开发效果的影响——以LP-133HF井为例[J]. 油气藏评价与开发, 2018,8(5):77-80.
[9]	DIAZ DE, SOUZA O C, SHARP A, MARTINEZ R C, et al. Integrated unconventional shale gas reservoir modeling: A worked example from the Haynesville shale, De Soto Parish, North Louisiana[C]// paper SPE-154692-MS presented at the SPE Americas Unconventional Resources Conference 5-7 June2012, Pittsburgh, Pennsylvania, USA.
[10]	YU W, SEPEHRNOORI K. Optimization of multiple hydraulically fractured horizontal wells in unconventional gas reservoirs[C]// paper SPE-164509-MS presented at the SPE Production and Operations Symposium, 23-26 March 2013, Oklahoma City, Oklahoma, USA
[11]	RAMANATHAN V, BOSKOVIC D, ZHMODIK A, et al. A simulation approach to modelling and understanding fracture geometry with respect to well spacing in multi well pads in the Duvernay-A case study[C]// paper SPE-175928-MS presented at the SPE/CSUR Unconventional Resources Conference, 20-22 October 2015, Calgary, Alberta, Canada.
[12]	AWADA A, SANTO M, LOUGHEED D, et al. Is that interference? A workflow for identifying and analyzing communication through hydraulic fractures in a multi-well pad[C]// paper URTEC-2148963-MS presented at the Unconventional Resources Technology Conference, 20-22 July 2015, San Antonio, Texas, USA.
[13]	SCHOFIELD J, RODRIGUEZ-HERRERA A, GARCIA-TEIJEIRO X. Optimization of well pad & completion design for hydraulic fracture stimulation in unconventional reservoirs[C]// paper SPE-174332-MS presented at the EUROPEC 2015, 1-4 June 2015, Madrid, Spain.
[14]	安永生, 吴晓东, 韩国庆 . 基于混合PEBI网格的复杂井数值模拟应用研究[J].中国石油大学学报(自然科学版), 2007(6):60-63.
[15]	蔡强, 杨钦, 孟宪海 , 等. 二维PEBI网格的生成[J]. 工程图学学报, 2005,26(2):69-72.
[16]	李玉坤, 姚军 . 复杂断块油藏Delaunay三角网格自动剖分技术[J].油气地质与采收率, 2006(3):58-60.
[17]	MAYERHOFER M J, STEGENT N A, BARTH J O, et al. Integrating Fracture Diagnostics and Engineering Data in the Marcellus Shale[C]// paper SPE-145463-MS presented at the SPE Annual Technical Conference and Exhibition, 30 October-2 November 2011, Denver, Colorado, USA.
[18]	庄惠农 . 气藏动态描述和试井[M]. 北京: 石油工业出版社, 2004.
[19]	魏明强, 段永刚, 方全堂 , 等. 页岩气藏压裂水平井产量递减曲线分析法[J]. 天然气地球科学, 2016,27(5):898-904. doi: 10.11764/j.issn.1672-1926.2016.05.0898
[20]	陈辉, 孙秀芝, 吕广忠 . 压裂水平井裂缝布局研究[J]. 石油天然气学报, 2013,35(1):141-144.

外区储层孔隙度（φ₂）	储层有效厚度（h）/m	各压裂水平井井底流压（P_wf）/MPa	天然气相对密度（r_g）	内区渗透率（k₁）/10^-3μm²	Langmuir压力（P_L）/MPa
0.05	16	12	0.57	0.05	10.4
裂缝半长(x_f)/m	Langmuir体积（V_L）/ （m³·m^-3）	综合扩散系数（D_k）/ （m²·s^-1）	压裂水平井间距（D_r）/m	各SRV区储层孔隙度（φ₁）	压裂水平井井数（N）/个
125	3	1×10^-9	500	0.08	3
原始地层压力（p_i）/MPa	储层温度/℃	外区渗透率（k₂）/10^-3μm²	裂缝间距（d_f）/m	裂缝数量（n_f）/条	水平井长度（L）/m
20	60	5×10^-4	100	10	1 000