多重伤害机制下的疏松砂岩裂缝导流能力变化规律

Variation of Fracture Conductivity in Unconsolidated Sands under the Multiple Damage Mechanisms

江锚 袁征 于继飞 张海龙 闫新江 夏金娜 陈学江 马宇奔

JIANG Mao YUAN Zheng YU Jifei ZHANG Hailong YAN Xinjiang XIA Jinna CHEN Xuejiang MA Yuben

中海油研究总院有限责任公司，北京　100028 中海油田服务股份有限公司油田生产事业部，天津　300452

CNOOC Research Institute Co., Ltd. Beijing 100028, China COSL Production Optimization, Tianjin 300452, China

为了明确支撑剂嵌入和微粒运移两种伤害机制对疏松砂岩裂缝导流能力的影响，以人工研制疏松砂岩岩样为研究对象，使用不同粒径的陶粒作为支撑剂，开展了悬浮液注入条件下的疏松砂岩导流能力试验，评价了工程和地质因素对支撑剂嵌入深度和裂缝导流能力的影响。结果表明，铺砂浓度增大能增强导流能力，悬浮液浓度、支撑剂目数和流量的增大会导致导流能力减弱。岩石胶结强度增大、闭合压力降低、支撑剂目数和铺砂浓度增加会使嵌入深度减小，有效缓解嵌入导致的裂缝剥蚀。其中，支撑剂目数增加会使得导流能力减小。相同条件下，流速越大导致导流能力减小，同时也会影响后续的裂缝导流能力。该研究对于后期的油井防砂工作具有重要意义。

In order to clarify the influence of two damage mechanisms of proppant embedment and particle migration on the conductivity of loose sandstone fractures, taking the artificially developed loose sandstone samples as the research object, the conductivity test of loose sandstone was carried out under the condition of suspension injection by using ceramic with different particle sizes as proppant. The influence of engineering and geological factors on proppant embedment depth and fracture conductivity was evaluated. The results show that the increase of sand concentration can enhance the conductivity, and the increase of suspension concentration, proppant mesh and flow rate can reduce the conductivity. The increase of rock cementation strength, the decrease of closure pressure, the increase of proppant mesh and sand concentration will lead to the decrease of embedment depth and effectively alleviate the fracture denudation caused by embedment. Among them, the increase proppant mesh will reduce the conductivity. Under the same conditions, the greater the flow rate, the smaller the conductivity, and it will also affect the subsequent fracture conductivity. This study is of great significance for the later sand control work of oil wells.

https://doi.org/10.3969/j.issn.1008-2336.2023.03.041