Tight volcanic reservoirs, characterized by strong heterogeneity and a well-developed fracture network, are usually difficult to develop. The development of effective ways to enhance production in such reservoirs is an important task in research work for oil and gas field development. The method of enhancing production by imbibition is a promising technology for oil recovery in tight reservoirs. In this paper, based on the production data of horizontal wells in tight volcanic reservoirs, we have studied the imbibition mechanism during fracturing fluid flowback. Nuclear magnetic resonance (NMR) technology was used for analysis. First, the wire-cutting technique was used to simulate fractures generated by hydraulic fracturing in the core. Then the core was filled with quartz sand. Then the migration of fluid between small pores and macropores during the imbibition process was studied by low-field NMR analysis. The research results show that the imbibition displacement of fracturing fluid under high pressure can effectively increase the recovery rate, while the soaking time can affect the imbibition exchange of fluid between crack and matrix. Due to the small pore radius and high capillary resistance of the volcanic rock, the imbibition stability time is longer. The pore size distribution of volcanic rock was analyzed quantitatively by NMR and mercury intrusion porosimetry. The results show that the dynamic imbibition process occurs mainly in pores less than 2 ìm.
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References
P. M. Oen, M. Engell-Jensen, and A. A. Barendregt, “Skjold field, Danish North sea: early evaluations of oil recovery through water imbibition in a fractured reservoir,” SPE 15569, SPE Reserv. Eng., 3(01), 17-22 (1988).
T. Babadagli and I. Ershaghi, “Imbibition assisted two-phase flow in natural fractures,” SPE 24044, SPE Western Regional Meeting, 30 March–1 April, Bakersfield, CA, USA (1992).
S. Al-Lawati and S. Saleh, “Oil recovery in fractured oil reservoirs by low IFT imbibition process,” SPE 36688, SPE Annual Technical Conference and Exhibition, 6-9 October, Denver, Colorado, USA (1996).
Y. Li and N. C. Wardlaw, “Mechanisms of nonwetting phase trapping during imbibition at slow rates,” J. Colloid Interface Sci., 109(2), 473-86 (1986).
L. Yang, H. Ge, X. Shi, et al., “Experimental and numerical study on the relationship between water imbibition and salt ion diffusion in fractured shale reservoirs,” J. Nat. Gas Sci. Eng., 38, 283-297 (2017).
Z. Yang, X. Liu, H. Li, Q. Lei, Y. Luo, and X. Wang, “Analysis on the influencing factors of imbibition and the effect evaluation of imbibition action in tight reservoirs,” Pet. Explor. Dev., 46(4), 1-7 (2007).
D. Xu, B. Bai, H. Wu, et al., “Mechanisms of imbibition enhanced oil recovery in low permeability reservoirs: effect of IFT reduction and wettability alteration,” Fuel, 224, 110-119 (2019).
T. Liang, F. Zhou, J. Lu, D. DiCarlo, and Q. Nguyen, “Evaluation of wettability alteration and IFT reduction on mitigating water blocking for low-permeability oil-wet rocks after hydraulic fracturing,” Fuel, 209, 650-660 (2017).
X. Wang, X. Peng, S. Zhang, Z. Du, and F. Zeng, “Characteristics of oil distributions in forced and spontaneous imbibition of tight oil reservoir,” Fuel, 224, 280-288 (2018).
R. Zhu, C. Zou, et al., “Characteristics and distribution of continental tight oil in China,” J. Asian Earth Sci., 178, 37-51 (2019).
S. Hu, Rþ Zhu, Sþ Wu, B. Bai, Z. Yang, and J. Cui, “Exploration and development of continental tight oil in China,” Pet. Explor. Dev., 45(4), 790-802 (2018).
Z. Cheng, Z. Ning, X. Yu, Q. Wang, and W. Zhang, “New insights into spontaneous imbibition in tight oil sandstones with NMR,” J. Pet. Sci. Eng., 179, 455-464 (2019).
Q. Ma, S. Yang, D. Lv, M. Wang, J. Chen, G. Kou, and L. Yang, “Experimental investigation on the influence factors and oil production distribution in different pore sizes during CO2 huff-and-puff in an ultra-high-pressure tight oil reservoir,” J. Pet. Sci. Eng., 178, 1155-1163 (2019).
J. J. Howard and E. A. Spinler, “Nuclear magnetic resonance measurements of wettability and uid saturations in chalk,” SPE Adv. Technol., 3(1), 60-65 (1995).
Q. You, H. Wang, Z. Yan, Y. Liu, J. Fang, and C. Dai, “Experimental study on spontaneous imbibition of recycled fracturing ow-back uid to enhance oil recovery in low permeability sandstone reservoirs,” J. Pet. Sci. Eng., 166, 375-380 (2018).
L. Yang, N. Dou, X. Lu, et al., “Advances in understanding imbibition characteristics of shale using an NMR technique: a comparative study of marine and continental shale,” J. Geophys. Eng.,15(4), 1363-1375 (2018).
J. Wang, H. Liu, J. Xia Jing, et al., “Mechanism simulation of oil displacement by imbibition in fractured reservoirs,” Pet. Explor. Dev., 44(5), 761-770 (2017).
A. Y. Foley, H. A. Nooruddin, and M. J. Blunt, “The impact of capillary backpressure on spontaneous counter-current imbibition in porous media,” Adv. Water Res., 107, 405-420 (2017).
S. Peng and X. Xiao, “Investigation of multiphase uid imbibition in shale through synchrotron-based dynamic micro-CT imaging,” J. Geophys. Res. Solid Earth, 122(6), 4475-4491 (2017).
M. Mirzaei and D. Dicarlo, “Imbibition of anionic surfactant solution into oil-wet capillary tubes,” Transp. Porous Media, 99(1), 37-54 (2013).
X. Gu, C. Pu, H. Huang, F. Huang, Y. Li, Y. Liu, and H. Liu, “Micro-influencing mechanism of permeability on spontaneous imbibition recovery for tight sandstone reservoirs,” Pet. Explor. Dev., 44(6), 948-954 (2017).
F. Wang and Z. Pan, “Numerical simulation of chemical potential dominated fracturing fluid flowback in hydraulically fractured shale gas reservoirs,” Pet. Explor. Dev., 43(6), 971-977 (2016).
P. Kathel and K. K. Mohanty, “EOR in tight oil reservoirs through wettability alteration,” SPE 166281, SPE Annual Technical Conference and Exhibition, 30 September–2 October, New Orleans, Luisiana, USA (2013).
C. Dai, R. Cheng, X. Sun, Y. Liu, H. Zhou, et al., “Oil migration in nanometer to micrometer sized pores of tight oil sandstone during dynamic surfactant imbibition with online NMR,” Fuel, 245, 544-553 (2019).
S. Deng, W. Lü, Q. Liu, Z. Leng, T. Li Tong, et al., “Research on displacement mechanism in conglomerate using CT scanning method,” Pet. Explor. Dev., 41(3), 365-370 (2014).
N. Jia, W. Lü, T. Chang, et al., “Anew method for precisely measuring core porosity with high efficiency and no destruction,” Acta Pet. Sin., 39(7), 824-828 (2018).
C. Yong, J. H. Zhang, Z. X. Zeng, et al., “Experimental investigation on oil migration and accumulation in tight sandstones,” J. Pet. Sci. Eng., 160, 267-275 (2018).
C. Lyu, Z. Ning, Q. Wang, and M. Chen, “Application of NMR T2 to pore size distribution and movable uid distribution in tight sandstones,” Energ. Fuel., 32(2), 1395-1405 (2018).
H. Gao and H. Li, “Determination of movable uid percentage and movable uid porosity in ultra-low permeability sandstone using nuclear magnetic resonance (NMR) technique,” J. Pet. Sci. Eng.,133, 258-267 (2015).
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This work was supported by Science and Technology Major Project of CNPC (No. 2017E-0405) and Science and Technology Project of CNPC (No. kt2017-18-05).
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Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 5, pp. 89 – 93, September – October, 2020.
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Kong, C., Wang, Z., Chang, T. et al. Novel Method for Studying, the, Imbibition Production Mechanism Using NMR. Chem Technol Fuels Oils 56, 844–851 (2020). https://doi.org/10.1007/s10553-020-01197-5
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DOI: https://doi.org/10.1007/s10553-020-01197-5