Experimental Study on Optimization of Acid-Fracturing Technique for Efficient Communication of Multi-Fracture-Cavity Structure Reservoirs
-
摘要: 缝洞型碳酸盐岩储层因缝洞连通复杂、结构多样导致改造困难，现有技术难以实现多缝洞体系高效动用。为此，研制多结构节点流动反应可视化实验装置，采用固体缓速酸开展酸压实验，观测流体路径并分析酸液浓度影响规律，提出以无因次突破体积为判据的优化策略。实验表明：固体缓速酸可减少早中期酸耗，增强远端溶蚀增渗效果并延长支撑缝长；串联缝洞结构适用高浓度酸液，其可快速增压、缩短突破时间且减少用酸量；并联结构酸液优先进入未充填裂缝，高浓度酸液导致充填区流动困难，推荐低浓度酸或“暂堵剂+高浓度酸”复合工艺。研究揭示了酸液在复杂缝洞系统中的流动机制，为非均质碳酸盐岩储层高效改造提供技术支撑。Abstract: Fractured-vuggy carbonate reservoirs are difficult to stimulate because of the complex fracture and vug connection as well as the varied formation structures. Existing technologies cannot be used to efficiently produce the multiple fracture-and-vug reservoirs. To deal with this problem, a visual experimental device for multi-structure node flow reaction was developed and a solid retarded acid used in acid fracturing experiment. Using the experimental device and through the acid fracturing experiment, the flow path of the fracturing fluid was observed and the effects on the concentration of the acid were analyzed, and as a result, an optimization strategy based on dimensionless breakthrough volume as the criterion was proposed. Experimental results show that the solid retarded acid can reduce the acid consumption in the early and middle stages of the fracturing job, enhance the dissolution and permeability-increasing effects in the far-end, as well as extend the lengths of propped fractures. High concentration acid solutions are suitable for acidifying a series-connected fracture and vug structure, since the pressures inside the structure increase fast, the breakthrough time can be shortened, and the volume of acids required can be reduced. In a parallel-connected fracture and vug structure, the acid solution preferentially enters the unfilled fractures, and the use of a high concentration acid solution results in difficulty of flow in the filled areas. Thus, a low concentration acid solution or a “temporary plugging agent + high concentration acid solution” combination is recommended for use in acidifying parallel-connected structures. This study has revealed the flow mechanism of an acid solution in a complex fractured-vuggy structure, and provided a technical support for high-efficiency stimulation of heterogeneous carbonate reservoirs.
-
表 1 不同结构体特征参数
结构体
类型结构体
内腔参数结构体
名称结构体体积
参数设置长/
cm宽/
cm高/
cm裂缝宽度/
mm孔隙度/
%实际容积/
mL裂缝 20 5 4 未充填缝 3 240 充填缝 40 160 溶洞 18 10 10 大溶洞 66 1200 小溶洞 33 600 
下载: 导出CSV
表 2 实验岩样全岩分析结果
序号 矿物百分含量/% 黏土总量 石膏 石英 钾长石 斜长石 方解石 白云石 1 0.00 0.00 0.14 0.00 2.33 94.33 3.20 2 0.00 0.00 0.50 0.00 3.24 93.25 3.00
下载: 导出CSV
-
[1] 江怀友, 宋新民, 王元基, 等. 世界海相碳酸盐岩油气勘探开发现状与展望[J]. 海洋石油, 2008, 28(4): 6-13.JIANG Huaiyou, SONG Xinmin, WANG Yuanji, et al. Current situation and forecast of the world's carbonate oil and gas exploration and development[J]. Offshore Oil, 2008, 28(4): 6-13. [2] LUO M M, ZHOU H, LIANG Y P, et al. Horizontal and vertical zoning of carbonate dissolution in China[J]. Geomorphology, 2018, 322: 66-75. doi: 10.1016/j.geomorph.2018.08.039 [3] 王大鹏, 白国平, 徐艳, 等. 全球古生界海相碳酸盐岩大油气田特征及油气分布[J]. 古地理学报, 2016, 18(1): 80-92.WANG Dapeng, BAI Guoping, XU Yan, et al. Characteristics and hydrocarbon distribution of the Paleozoic giant marine carbonate rock oil-gas fields in the world[J]. Journal of Palaeogeography, 2016, 18(1): 80-92. [4] LAMONT-BLACK J, YOUNGER P L, FORTH R A, et al. A decision-logic framework for investigating subsidence problems potentially attributable to gypsum karstification[J]. Engineering Geology, 2002, 65(2/3): 205-215. [5] ZHANG H, CAI Z X, HAO F, et al. Hypogenic origin of paleocaves in the Ordovician carbonates of the southern Tahe oilfield, Tarim basin, northwest China[J]. Geoenergy Science and Engineering, 2023, 225: 211669. doi: 10.1016/j.geoen.2023.211669 [6] RABIE A I, NASR-EL-DIN H A. Measuring the reaction rate of lactic acid with calcite using the rotating disk apparatus[C]//SPE Middle East Oil and Gas Show and Conference. Manama, Bahrain: SPE, 2011: SPE 140167-MS. [7] SAYED M A, NASR-EL-DIN H A. Reaction rate of emulsified acids and dolomite[C]//SPE International Symposium and Exhibition on Formation Damage Control. Lafayette, Louisiana, USA: SPE, 2012: SPE 151815-MS. [8] 刘伟, 刘佳, 刘飞, 等. 高钙质致密油酸岩反应动力学参数试验研究[J]. 石油与天然气化工, 2015, 44(2): 91-95.LIU Wei, LIU Jia, LIU Fei, et al. Experimental study on reaction kinetics parameters of tight oil acid rock with high calcium[J]. Chemical Engineering of Oil and Gas, 2015, 44(2): 91-95. [9] LUND K, FOGLER H S, MCCUNE C C. Acidization—I. the dissolution of dolomite in hydrochloric acid[J]. Chemical Engineering Science, 1973, 28(3): IN1-691. [10] 陈赓良, 黄瑛. 碳酸盐岩酸化反应机理分析[J]. 天然气工业, 2006, 26(1): 104-108.CHEN Gengliang, HUANG Ying. An analysis of acidizing reaction mechanism of carbonates[J]. Natural Gas Industry, 2006, 26(1): 104-108. [11] 李沁. 高黏度酸液酸岩反应模拟试验新方法探索[D]. 成都: 成都理工大学, 2010.LI Qin. Exploration on a new lab method of simulation high-viscosity acid-rock reaction[D]. Chengdu: Chengdu University of Technology, 2010. [12] 王雪涛. 缝洞型油藏固体酸深部酸压工艺研究与应用[D]. 青岛: 中国石油大学(华东), 2020.WANG Xuetao. Research and application of deep acid fracturing technology of solid acid in fracture vuggy reservoir[D]. Qingdao: China University of Petroleum, 2020. [13] 董晓军, 张明, 蒲阳峰, 等. 一种酸压中氢离子有效传质系数的测试装置及测试方法: CN201510091460.4[P]. 2015-02-28.DONG Xiaojun, ZHANG Ming, PU Yangfeng, et al. A testing device and method for measuring the effective mass transfer coefficient of hydrogen ions in acid pressure: CN201510091460.4[P]. 2015-02-28. [14] 刘飞, 罗志锋, 周长林, 等. 大尺寸岩板测定酸液有效传质系数新方法[J]. 石油与天然气化工, 2019, 48(6): 53-58.LIU Fei, LUO Zhifeng, ZHOU Changlin, et al. A new method for testing acid effective mass transfer coefficient based on large scale rock sample[J]. Chemical engineering of oil & gas, 2019, 48(6): 53-58. [15] 戴一凡, 侯冰. 碳酸盐岩酸蚀裂缝面粗糙度与导流能力相关性分析[J]. 断块油气田, 2023, 30(4): 672-677.DAI Yifan, HOU Bing. Correlation analysis between acid-etched fracture surface roughness and fracture conductivity in carbonate reservoir[J]. Fault-Block Oil and Gas Field, 2023, 30(4): 672-677. [16] 夏熙, 牟建业, 张士诚, 等. 大牛地气田复杂岩性储层酸蚀裂缝导流能力规律研究[J]. 断块油气田, 2024, 31(6): 1083-1089.XIA Xi, MU Jianye, ZHANG Shicheng, et al. Study on conductivity of acid-etched fractures in complex-lithology reservoir of Daniudi gasfield[J]. Fault-Block Oil and Gas Field, 2024, 31(6): 1083-1089. [17] DAVIES D R, BOSMA M G R, DE V W. Development of field design rules for viscous fingering in acid fracturing treatments: a large-scale model study[C]//the Middle East Oil Show. Bahrain: SPE, 1987: SPE 15772-MS. [18] 李小刚, 杨兆中, 陈锐, 等. 前置液酸压缝中酸液指进的物模与分形研究[J]. 西南石油大学学报, 2007, 29(6): 105-108.LI Xiaogang, YANG Zhaozhong, CHEN Rui, et al. Physical simulation and fractal features of acid fingering in pad acid fracturing treatment[J]. Journal of Southwest Petroleum University, 2007, 29(6): 105-108. [19] 罗志锋, 余洋, 赵立强, 等. 多因素下多级交替注入酸液指进实验研究[J]. 油气藏评价与开发, 2018, 8(4): 36-41.LUO Zhifeng, YU Yang, ZHAO Liqiang, et al. Multifactorial experiment of acid's fingering phenomenon in the multi-stage alternating injection of acid fracturing[J]. Reservoir Evaluation and Development, 2018, 8(4): 36-41. [20] 宋志峰, 张建光. 缝洞型碳酸盐岩靶向酸压目标体分类与建模[J]. 地质科技通报, 2021, 40(3): 78-84.SONG Zhifeng, ZHANG Jianguang. Classification and modeling of targeted fracture-cave bodies in acid fracturing[J]. Bulletin of Geological Science and Technology, 2021, 40(3): 78-84. [21] 安娜, 罗攀登, 李永寿, 等. 碳酸盐岩储层深度酸压用固体颗粒酸的研制[J]. 石油钻探技术, 2020, 48(2): 93-97.AN Na, LUO Pandeng, LI Yongshou, et al. Development of solid granular acid for the deep acid-fracturing of carbonate reservoirs[J]. Petroleum Drilling Techniques, 2020, 48(2): 93-97. [22] 刘会锋, 崔龙连, 刘琦, 等. 阿布扎比NEB油田超长水平井限流筛管完井与酸化优化设计[J]. 钻采工艺, 2022, 45(6): 53-58.LIU Huifeng, CUI Longlian, LIU Qi, et al. Optimization design of limited entry liner completion and acidizing for ultra-long lateral horizontal wells in NEB oilfield, Abu Dhabi[J]. Drilling & Production Technology, 2022, 45(6): 53-58. -
点击查看大图
图(10) / 表(2)
计量
- 文章访问数: 3
- HTML全文浏览量: 2
- PDF下载量: 0
- 被引次数: 0
