为明确聚表二元复合体系对不同模态岩心的驱替特征和剩余油动用规律,选用3种典型孔隙结构的天然岩心,分别从孔隙、岩心和矿场3个尺度研究孔隙结构差异对二元复合驱提高采收率的影响：①利用核磁共振原位驱替实验研究水驱、二元复合驱过程中各种孔隙结构岩心中的剩余油变化规律;②采用全直径岩心驱替实验研究不同孔隙结构岩心的驱替特征与驱替效果;③利用矿场开发数据对比双模态砂岩和复模态砾岩储集层二元复合驱开发特征的差异。研究结果表明：孔隙结构越复杂,水驱效果越差,二元复合驱提高采收率幅度越大;二元复合驱可以增加对单模态和双模态岩心中1~3 μm孔隙区间内剩余油的动用程度,但复模态岩心仍以动用孔隙半径大于3 μm孔隙区间内的剩余油为主;全直径岩心驱替实验表明二元复合驱体系的注入可大幅提升复模态岩心的驱替压力,同时乳化岩心中的剩余油,有效扩大波及体积,进而大幅提高采收率;与砂岩油藏相比,复模态孔隙结构的砾岩油藏更容易发生窜流,实施化学驱提高采收率,必须解决宏观高渗通道的封堵与微观孔隙结构差异导致的波及效率等问题。图14表6参19
刘哲宇
,
李宜强
,
冷润熙
,
刘振平
,
陈鑫
,
HEJAZI Hossein
. 孔隙结构对砾岩油藏聚表二元复合驱提高采收率的影响[J]. 石油勘探与开发, 2020
, 47(1)
: 129
-139
.
DOI: 10.11698/PED.2020.01.12
To understand the displacement characteristics and remaining oil displacement process by the surfactant/polymer (SP) flooding in cores with different pore structures, the effects of pore structure on the enhanced oil recovery of SP flooding was investigated at the pore, core and field scales through conducting experiments on natural core samples with three typical types of pore structures. First, the in-situ nuclear magnetic resonance core flooding test was carried out to capture the remaining oil variation features in the water flooding and SP flooding through these three types of cores. Subsequently, at the core scale, displacement characteristics and performances of water flooding and SP flooding in these three types of cores were evaluated based on the full-size core flooding tests. Finally, at the field scale, production characteristics of SP flooding in the bimodal sandstone reservoir and multimodal conglomerate reservoir were compared using the actual field production data. The results show: as the pore structure gets more and more complex, the water flooding performance gets poorer, but the incremental recovery factor by SP flooding gets higher; the SP flooding can enhance the producing degree of oil in 1-3 μm pores in the unimodal and bimodal core samples, while it produces largely oil in medium and large pores more than 3 μm in pore radius in the multimodal core sample. The core flooding test using full-size core sample demonstrates that the injection of SP solution can significantly raise up the displacement pressure of the multimodal core sample, and greatly enhance recovery factor by emulsifying the remaining oil and enlarging swept volume. Compared with the sandstone reservoir, the multimodal conglomerate reservoir is more prone to channeling. With proper profile control treatments to efficiently enlarge the microscopic and macroscopic swept volumes, SP flooding in the conglomerate reservoir can contribute to lower water cuts and longer effective durations.
[1] 谭峰奇, 许长福, 王晓光, 等. 砾岩油藏水驱与聚合物驱微观渗流机理差异[J]. 石油学报, 2016, 37(11): 1414-1427.
TAN Fengqi, XU Changfu, WANG Xiaoguang, et al.Differences in microscopic porous flow mechanisms of water flooding and polymer flooding for conglomerate reservoir[J]. Acta Petrolei Sinica, 2016, 37(11): 1414-1427.
[2] 许长福, 刘红现, 钱根宝, 等. 克拉玛依砾岩储集层微观水驱油机理[J]. 石油勘探与开发, 2011, 38(6): 725-732.
XU Changfu, LIU Hongxian, QIAN Genbao, et al.Microcosmic mechanisms of water-oil displacement in conglomerate reservoirs in Karamay Oilfield, NW China[J]. Petroleum Exploration and Development, 2011, 38(6): 725-732.
[3] 刘卫东, 罗莉涛, 廖广志, 等. 聚合物-表面活性剂二元驱提高采收率机理实验[J]. 石油勘探与开发, 2017, 44(4): 600-607.
LIU Weidong, LUO Litao, LIAO Guangzhi, et al.Mechanism for enhanced oil recovery of polymer/surfactant binary flooding[J]. Petroleum Exploration and Development, 2017, 44(4): 600-607.
[4] RAEINI A Q, BIJELJIC B, BLUNT M J.Modeling capillary trapping using finite-volume simulation of two-phase flow directly on micro-CT images[J]. Advances in Water Resources, 2015, 83: 102-110.
[5] BAZAZI P, GATES I D, NEZHAD A S.Silica-based nanofluid heavy oil recovery a microfluidic approach[R]. SPE 185008, 2017.
[6] NOGUEIRA G L, CARVALHO M S, ALVARADO V.Dynamic network model of mobility control in emulsion flow through porous media[J]. Transport in Porous Media, 2013, 98(2): 427-441.
[7] LI Yiqiang, YANG Yan, SUN Xianda, et al.The application of laser confocal method in microscopic oil analysis[J]. Journal of Petroleum Science and Engineering, 2014, 120: 52-60.
[8] LI Junjian, JIANG Hanqiao, WANG Chuan, et al.Pore-scale investigation of microscopic remaining oil variation characteristics in water-wet sandstone using CT scanning[J]. Journal of Natural Gas Science and Engineering, 2017, 48: 36-45.
[9] ZHANG Y, NEZHAD A S, HEJAZI H S.Geo-material surface modification of microchips using layer-by-layer (LBL) assembly for subsurface energy and environmental applications[J]. Lab on a Chip, 2018, 18(2): 285-295.
[10] FREEDMAN R, HEATON N, FLAUM M, et al.Wet ability, saturation, and viscosity from NMR measurements[J]. SPE Journal, 2003, 8(4): 317-327.
[11] LIANG Bin, JIANG Hanqiao, LI Junjian, et al.Mechanism study of disproportionate permeability reduction using nuclear magnetic resonance T2[J]. Energy & Fuels, 2018, 32(4): 4959-4968.
[12] LIU Zheyu, LI Yiqiang, CUI Minghui, et al.Pore-scale investigation of residual oil displacement in surfactant-polymer flooding using nuclear magnetic resonance experiments[J]. Petroleum Science, 2016, 13(1): 91-99.
[13] 赵光, 戴彩丽, 由庆. 冻胶分散体软体非均相复合驱油体系特征及驱替机理[J]. 石油勘探与开发, 2018, 45(3): 464-473.
ZHAO Guang, DAI Caili, YOU Qing.Characteristics and displacement mechanisms of the dispersed particle gel soft heterogeneous compound flooding system[J]. Petroleum Exploration and Development, 2018, 45(3): 464-473.
[14] 韩海水, 马德胜, 李实, 等. 全直径砾岩长岩心水驱后烟道气驱油与埋存实验[J]. 石油勘探与开发, 2018, 45(5): 847-852.
HAN Haishui, MA Desheng, LI Shi, et al.Investigation of flue gas displacement and storage after the water flooding in full diameter conglomerate long core[J]. Petroleum Exploration and Development, 2018, 45(5): 847-852.
[15] CLARKE R H.Reservoir properties of conglomerates and conglomeratic sandstones[J]. AAPG Bulletin, 1979, 63(5): 799-803.
[16] 刘敬奎. 砾岩储层结构模态及储层评价探讨[J]. 石油勘探与开发, 1983, 10(2): 45-56.
LIU Jingkui.An investigation on structure model of conglomeratic reservoir and its evaluation[J]. Petroleum Exploration and Development, 1983, 10(2): 45-56.
[17] LIU Zheyu, CHENG Hongjie, XU Changfu, et al.Effect of lithology on pore-scale residual oil displacement in chemical flooding using nuclear magnetic resonance experiments[R]. SPE 190450, 2018.
[18] LIU Zheyu, LI Yiqiang, LYU Jianrong, et al.Optimization of polymer flooding design in conglomerate reservoirs[J]. Journal of Petroleum Science and Engineering, 2017, 152: 267-274.
[19] 宋鸿斌. 二元复合驱见效特征及影响因素研究: 以孤东油田为例[J]. 天然气地球科学, 2014, 25(S1): 98-106.
SONG Hongbin.Research of surfactant-polymer flooding response characteristics and influencing factors: Case of Gudong Oilfield[J]. Natural Gas Geoscience, 2014, 25(S1): 98-106.
