致密岩心带压渗吸规律实验研究

江昀; 许国庆; 石阳; 余玥; 王天一; 曾星航; 郑伟

doi:10.11781/sysydz202101144

致密岩心带压渗吸规律实验研究

doi: 10.11781/sysydz202101144

江昀^1,,
许国庆²,
石阳^1, ,,
余玥³,
王天一¹,
曾星航²,
郑伟¹

1.
中国石油勘探开发研究院, 北京 100083
2.
中国石化石油工程技术研究院, 北京 100101
3.
中国石油西南油气田分公司, 成都 610056

基金项目:

国家科技重大专项“致密油储层高效体积改造技术” 2016ZX05046-004

详细信息

作者简介:
江昀(1990-), 男, 博士, 工程师, 从事非常规储层改造基础理论研究。E-mail: jiangyun119@petrochina.com.cn

通讯作者:
石阳(1983-), 男, 高级工程师, 从事油气藏改造与保护。E-mail: shy312@petrochina.com.cn

中图分类号: TE311
计量
- 文章访问数: 662
- HTML全文浏览量: 173
- PDF下载量: 97
- 被引次数: 0
出版历程
- 收稿日期: 2020-06-19
- 修回日期: 2020-10-10
- 刊出日期: 2021-01-28

Forced imbibition in tight sandstone cores

1.
PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China
2.
SINOPEC Research Institute of Petroleum Engineering, Beijing 100101, China
3.
PetroChina Southwest Oil & Gas Field Company, Chengdu, Sichuan 610056, China

摘要

摘要: 致密油藏体积改造压后闷井过程中发生的渗吸置换，通常在压差（基质外部流体压力与孔隙压力之差）作用下进行，但渗吸置换物理模拟却通常在常压下进行（即自发渗吸），带压条件下的渗吸置换特征尚未提及。为研究压差作用下的渗吸置换（即带压渗吸）规律，首先，建立基于低场核磁共振测试技术的带压渗吸实验方法；其次，分析自发/带压渗吸的异同；最后，建立带压渗吸无因次时间模型。结果表明，质量分数为96.76%~97.25%的油相集中分布于纳米孔（1 ms ≤ T₂ ≤ 100 ms）内，纳米孔是主要储集空间；相比于自发渗吸，带压渗吸置换效率大幅提升是由强化的渗吸作用和压实作用共同造成的；岩心尺度建立的带压渗吸无因次时间模型可行，为确定油藏尺度压后闷井时间提供了新思路。
- 致密砂岩 /
- 带压渗吸 /
- 低场核磁共振测试 /
- 无因次时间模型 /
- 闷井时间
Abstract: Spontaneous imbibition (SI) generally occurs under forced pressure (pressure difference between hydraulic fluid pressure and original pore pressure) during a shut-in period. However, the experimental study of SI is commonly performed at atmospheric pressure and the effect of forced pressure is often neglected. In this study, the mechanism of SI in tight sandstone samples under forced pressure (forced imbibition, FI) was studied. A new experimental method for forced imbibition was firstly constructed based on low-field nuclear magnetic resonance(LF-NMR) measurements. After that, a correlation between SI and FI was discussed. Finally, a new dimensionless time model considering the effect of forced pressure for FI was constructed. The results showed that 96.76%-97.25% wt% of the oil was distributed in nano-pores (0.1 ms ≤ T₂ ≤ 100 ms) of core samples, occupying the major pore space. The ultimate oil recovery for FI was significantly improved relative to that of SI, which was associated with the synergetic effect of enhanced SI and compaction. The new dimensionless time model for FI was proved to be effective and it provides a new method to calculate shut-in time at field scale.
- tight sandstone /
- forced imbibition /
- LF-NMR /
- dimensionless time model /
- shut-in time

HTML全文

图 1 压后闷井过程中两相渗流区域示意

Figure 1. Schematic diagram for two-phase flow regions during shut-in period

下载: 全尺寸图片幻灯片

图 2 渗吸作用主导的两相渗流区内压差作用下逆向渗吸示意

Figure 2. Counter-current imbibition under forced pressure in two-phase seepage zone dominated by imbibition

下载: 全尺寸图片幻灯片

图 3 自发/带压渗吸实验装置示意

Figure 3. Schematic diagram of experimental devices for spontaneous imbition/forced imbition

下载: 全尺寸图片幻灯片

图 4 高压压汞测试中孔隙直径分布结果(a) 和低场核磁共振T₂谱(b)

Figure 4. Pore size distribution of core samples (a) and T₂ by Low-field nuclear magnetic resonance (b) in high pressure mercury injection

下载: 全尺寸图片幻灯片

图 5 自发/带压渗吸置换效率随时间(a)和时间平方根(b)变化关系曲线

Figure 5. Oil recovery for SI/FI vs. imbibition time (a) and its square root (b)

下载: 全尺寸图片幻灯片

图 6 有效孔隙半径随有效应力变化关系曲线

Figure 6. Effective pore radius vs. net confining stress

下载: 全尺寸图片幻灯片

图 7 自发渗吸T₂谱及孔隙油相分布(a) 和选定时间节点测定的T₂谱渗吸实验前后纳米孔隙内油相分布(b)

Figure 7. T₂ distribution during SI and corresponding frequency of oil distribution in pores at selected time intervals (a) and frequency of oil distribution in nanopores before and after SI (b)

下载: 全尺寸图片幻灯片

图 8 带压渗吸T₂谱及孔隙油相分布(a-d) 和选定时间节点测定的T₂谱渗吸实验前后纳米孔隙内油相分布(e-h)

Figure 8. T₂ distribution during FI and corresponding frequency of oil distribution in pores at selected time intervals (a-d) and frequency of oil distribution in nanopores before and after FI (e-h)

下载: 全尺寸图片幻灯片

图 9 渗吸置换效率随无因次时间变化关系曲线

Figure 9. Oil recovery as a function of dimensionless time

下载: 全尺寸图片幻灯片

表 1 带压渗吸实验岩心样品物性参数

Table 1. Petrophysical properties of tight core samples for forced imbibition experiment

类别	编号	深度/m	直径/cm	长度/cm	渗透率/(10^-3 μm²)	孔隙度/%
高压压汞	A11	2 179.7	2.51	1.76	0.034	10.54
	A12	2 179.9	2.53	1.71	0.030	9.71
	A13	2 180.4	2.53	1.70	0.048	12.53
	A14	2 180.6	2.53	1.72	0.031	8.79
	A15	2 180.6	2.53	1.71	0.049	11.32
自发/带压渗吸	A21	2 179.7	2.51	5.21	0.034	10.54
	A22	2 179.9	2.53	5.26	0.030	9.71
	A23	2 180.4	2.53	4.96	0.048	12.53
	A24	2 180.6	2.53	5.23	0.031	8.79
	A25	2 180.6	2.53	4.60	0.049	11.32
接触角	B11	2 176.6	2.53	1.35	0.048	12.37
	B12	2 177.6	2.53	1.28	0.057	10.69
	B13	2 178.4	2.53	1.32	0.023	8.42
含油量标定	B21	2 176.6	2.53	3.62	0.048	12.37
	B22	2 177.6	2.53	3.66	0.057	10.69
	B23	2 178.4	2.53	3.61	0.023	8.42
脉冲衰减	C1	2 179.2	2.51	3.24	0.026	10.25
	C2	2 180.5	2.52	3.21	0.015	7.57
	C3	2 180.8	2.52	3.27	0.037	10.67
	C4	2 180.7	2.53	3.51	0.014	7.36

下载: 导出CSV

表 2 带压渗吸实验流体样品物性参数(20 ℃, 1 atm)

Table 2. Physical properties of fluid samples for forced imbibition experiment

流体类型	密度/(g·cm^-3)	黏度/(mPa·s)	界面张力/(mN·m^-1)
煤油	0.83	2.53	26.82
氘水	1.09	1.25	72.75

下载: 导出CSV

表 3 平均值法表面弛豫率计算结果

Table 3. Calculation results of surface relaxation by average method

岩心编号	T_2LM/ms	R_p/nm	ρ/(μm·s^-1)
A21	3.11	34.2	2.75
A22	5.49	78.2	3.56
A23	2.08	58.5	7.02
A24	1.29	55.3	10.68
A25	3.20	81.4	6.37

下载: 导出CSV

表 4 基于低场核磁T₂值的孔隙类型分类

Table 4. Pore size classification based on T₂ value by low-field nuclear magnetic resonance

T₂/ms	孔隙直径/nm	孔隙类型
0.1~100	1~1 000	纳米孔
≥100	≥1 000	微孔/中孔

下载: 导出CSV

表 5 气体滑脱因子与平均孔隙半径计算结果

Table 5. Gas slippage factor and average pore radius

岩心编号	有效应力/MPa	克氏渗透率/(10^-3μm²)	气体滑脱因子/MPa	有效孔隙半径/μm
C1	2.5	0.016 0	0.34	0.53
	5.0	0.007 8	0.59	0.31
	10.0	0.002 0	1.42	0.13
	15.0	0.001 0	3.22	0.06
C2	2.5	0.009 5	0.60	0.30
	5.0	0.008 1	0.80	0.23
	10.0	0.001 6	1.45	0.13
	15.0	0.000 6	1.81	0.10
C3	2.5	0.018 0	0.38	0.48
	5.0	0.004 1	1.29	0.14
	10.0	0.002 1	1.90	0.10
	15.0	0.001 1	2.02	0.09
C4	2.5	0.009 2	0.56	0.33
	5.0	0.004 2	1.23	0.15
	10.0	0.003 6	1.99	0.09
	15.0	0.001 1	4.35	0.05

下载: 导出CSV

参考文献(33)

[1]	郭秋麟, 武娜, 陈宁生, 等. 鄂尔多斯盆地延长组第7油层组致密油资源评价[J]. 石油学报, 2017, 38(6): 658-665. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB201706005.htm GUO Qiulin, WU Na, CHEN Ningsheng, et al. An assessment of tight oil resource in 7th oil reservoirs of Yanchang Formation, Ordos Basin[J]. Acta Petrolei Sinica, 2017, 38(6): 658-665. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB201706005.htm
[2]	李忠兴, 屈雪峰, 刘万涛, 等. 鄂尔多斯盆地长7段致密油合理开发方式探讨[J]. 石油勘探与开发, 2015, 42(2): 217-221. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201502012.htm LI Zhongxing, QU Xuefeng, LIU Wantao, et al. Development modes of Triassic Yanchang Formation Chang 7 member tight oil in Ordos Basin, NW China[J]. Petroleum Exploration and Development, 2015, 42(2): 217-221. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201502012.htm
[3]	GHANBARI E, ABBASI M A, DEHGHANPOUR H, et al. Flowback volumetric and chemical analysis for evaluating load reco-very and its impact on early-time production[C]//SPE Unconventional Resources Conference Canada. Calgary, Alberta: Society of Petroleum Engineers, 2013.
[4]	CARPENTER C. Impact of liquid loading in hydraulic fractures on well productivity[J]. Journal of Petroleum Technology, 2013, 65(11): 162-165. doi: 10.2118/1113-0162-JPT
[5]	GHANBARI E, DEHGHANPOUR H. The fate of fracturing water: a field and simulation study[J]. Fuel, 2016, 163: 282-294. doi: 10.1016/j.fuel.2015.09.040
[6]	WANG Dongmei, BUTLER R, LIU Hong, et al. Flow-rate behavior and imbibition in shale[J]. SPE Reservoir Evaluation & Engineering, 2011, 14(4): 485-492.
[7]	DEHGHANPOUR H, LAN Q, SAEED Y, et al. Spontaneous imbibition of brine and oil in gas shales: effect of water adsorption and resulting microfractures[J]. Energy Fuels, 2013, 27(6): 3039-3049. doi: 10.1021/ef4002814
[8]	KATHEL P, MOHANTY K K. Wettability alteration in a tight oil reservoir[J]. Energy Fuels, 2013, 27(11): 6460-6468. doi: 10.1021/ef4012752
[9]	HABIBI A, XU M, DEHGHANPOUR H, et al. Understanding rock-fluid interactions in the montney tight oil play[C]//SPE/CSUR Unconventional Resources Conference. Calgary, Alberta, Canada: SPE, 2015.
[10]	HABIBI A, BINAZADEH M, DEHGHANPOUR H, et al. Advances in understanding wettability of tight oil formations[C]//SPE AnnualTechnical Conference and Exhibition. Houston, Texas: Society of Petroleum Engineers, 2015.
[11]	RAEESI B. Measurement and pore-scale modelling of capillary pressure hysteresis in strongly water-wet sandstones[D]. Laramie, Wyoming: University of Wyoming, 2012.
[12]	HATIBOGLU C U, BABADAGLI T. Oil recovery by counter-current spontaneous imbibition: effects of matrix shape factor, gravity, IFT, oil viscosity, wettability, and rock type[J]. Journal of Petroleum Science and Engineering, 2007, 59(1/2): 106-122.
[13]	AL-ATTAR H H. Experimental study of spontaneous capillary imbibition in selected carbonate core samples[J]. Journal of Petroleum Science and Engineering, 2010, 70(3/4): 320-326.
[14]	IFFLY R, ROUSSELET D C, VERMEULEN J L. Fundamental study of imbibition in fissured oil fields[C]//Fall Meeting of the Society of Petroleum Engineers of AIME. San Antonio, Texas: Society of Petroleum Engineers, 1972.
[15]	FATT I. The effect of overburden pressure on relative permeability[J]. Journal of Petroleum Technology, 1953, 5(10): 15-16. doi: 10.2118/953325-G
[16]	TIAN Xiaofeng, CHENG Linsong, CAO Renyi, et al. A new approach to calculate permeability stress sensitivity in tight sandstone oil reservoirs considering micro-pore-throat structure[J]. Journal of Petroleum Science and Engineering, 2015, 133: 576-588. doi: 10.1016/j.petrol.2015.05.026
[17]	SHAR A M, MAHESAR A A, CHANDIO A D, et al. Impact of confining stress on permeability of tight gas sands: an experimental study[J]. Journal of Petroleum Exploration and Production Technology, 2017, 7(3): 717-726. doi: 10.1007/s13202-016-0296-9
[18]	ZHANG Xiaoyun, MORROW N R, MA Shouxiang. Experimental verification of a modified scaling group for spontaneous imbibition[J]. SPE Reservoir Engineering, 1996, 11(4): 280-285. doi: 10.2118/30762-PA
[19]	MA Shouxiang, MORROW N R, ZHANG Xiaoyun. Generalized scaling of spontaneous imbibition data for strongly water-wet systems[J]. Journal of Petroleum Science and Engineering, 1997, 18(3/4): 165-178.
[20]	SCHMID K S, GEIGER S. Universal scaling of spontaneous imbibition for arbitrary petrophysical properties: water-wet and mixed-wet states and Handy's conjecture[J]. Journal of Petroleum Science and Engineering, 2013, 101: 44-61. doi: 10.1016/j.petrol.2012.11.015
[21]	MASON G, FISCHER H, MORROW N R, et al. Correlation for the effect of fluid viscosities on counter-current spontaneous imbibition[J]. Journal of Petroleum Science and Engineering, 2010, 72(1/2): 195-205.
[22]	STANDNES D C, ANDERSEN P Ø. Analysis of the impact of fluid viscosities on the rate of countercurrent spontaneous imbibition[J]. Energy & Fuels, 2017, 31(7): 6928-6940.
[23]	SAIDIAN M, KUILA U, RIVERA S, et al. Porosity and pore size distribution in mudrocks: a comparative study for Haynesville, Niobrara, Monterey and eastern European Silurian formations[C]//SPE/AAPG/SEG Unconventional Resources Technology Conference. Denver, Colorado: Unconventional Resources Technology Conference, 2014.
[24]	EL SAYED A M A, ELSAYED N A. Petrophysical properties of clastic reservoirs using NMR relaxometry and mercury injection data: Bahariya Formation, Egypt[J]. IOP Conference Series: Earth and Environmental Science, 2016, 44(4): 042018.
[25]	ZHAO Huawei, NING Zhengfu, WANG Qing, et al. Petrophysical characterization of tight oil reservoirs using pressure-controlled porosimetry combined with rate-controlled porosimetry[J]. Fuel, 2015, 154: 233-242. doi: 10.1016/j.fuel.2015.03.085
[26]	TINNI A, ODUSINA E, SULUCARNAIN I, et al. Nuclear-magnetic-resonance response of brine, oil, and methane in organic-rich shales[J]. SPE Reservoir Evaluation & Engineering, 2015, 18(3): 400-406.
[27]	WASHBURN E W. The dynamics of capillary flow[J]. Physical Review, 1921, 17(3): 273-283. doi: 10.1103/PhysRev.17.273
[28]	SAIDIAN M, PRASAD M. Effect of mineralogy on nuclear magnetic resonance surface relaxivity: a case study of Middle Bakken and Three Forks formations[J]. Fuel, 2015, 161: 197-206. doi: 10.1016/j.fuel.2015.08.014
[29]	KLINKENBERG L J. The permeability of porous media to liquids and gases[C]//. Drilling and Production Practice. New York: SPE, 1941: 200-213.
[30]	LOUCKS R G, REED R M, RUPPEL S C, et al. Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores[J]. AAPG Bulletin, 2012, 96(6): 1071-1098. doi: 10.1306/08171111061
[31]	TIAB D, DONALDSON E C. Petrophysics[M]. 3rd ed. Amsterdam: Gulf Professional Publishing, 2012: 371-418.
[32]	LEVERETT M C. Capillary behavior in porous solids[J]. Transactions of the AIME, 1941, 142(1): 152-169. doi: 10.2118/941152-G
[33]	LAN Qing, GHANBARI E, DEHGHANPOUR H, et al. Water loss versus soaking time: spontaneous imbibition in tight rocks[J]. Energy Technology, 2014, 2(12): 1033-1039. doi: 10.1002/ente.201402039