榆林储气库高气量纤维网络抗支撑剂回流实验

Experimental study on proppant reflux resistance of fiber network under high gas injection rate in Yulin gas storage

胡阳明,赵振峰,李宪文,陈宝春,李喆

低渗透油气田勘探开发国家工程实验室，陕西 西安 710018 中国石油长庆油田分公司油气工艺研究院，陕西 西安 710018

National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Field, Xi′an 710018, China Oil ＆ Gas Technology Research Institute, Changqing Oilfield Company, PetroChina, Xi′an 710018, China

为满足地下储气库季节调峰“快进快出”及“多注多采”的要求，低渗气藏储气库井通常需要压裂改造。聚丙烯纤维具有握裹力强、弹性模量大、分散性佳的特点，在压裂液中添加聚丙烯纤维，可与支撑剂颗粒互绕形成网络结构，抵抗支撑剂回流。文中基于裂缝导流能力评价指标，从纤维网络形态、陶粒支撑剂大小、铺砂浓度、纤维与支撑剂的质量比和纤维长度等方面，设计出砂与不出砂2种实验，综合评价聚丙烯纤维网络抗支撑剂回流能力。结果表明：选用长庆20/40目陶粒支撑剂、铺砂浓度12.6 kg/m²、纤维与支撑剂的质量比大于0.010、纤维长度大于10 mm的裂缝支撑剂设计，在高注气量下抗支撑剂回流控砂效果最好。研究结果可为低渗气藏储气库注采井压裂施工的支撑剂设计和防砂、控砂提供理论依据。

In order to meet the requirement of "rapid injection and rapid recovery" and "more injection and more recovery" for the seasonal peak regulation of the underground gas storage, the gas storage well of the low-permeability gas reservoir usually needs hydraulic fracturing. By taking advantage of the characteristics of strong holding force, large elastic modulus and good dispersion of polypropylene fiber, a certain amount of polypropylene fiber was added into the fracturing fluid to form fiber network and resist proppant reflux. Meanwhile, based on the evaluation standard of fracture conductivity, two experimental methods of sand-producing and sand-free were designed from the perspectives of fiber network forms, ceramsite proppant particle size, sand concentration, mass ratio of fiber and proppant, fiber length to comprehensively evaluate the proppant reflux resistance of polypropylene fiber network. The experimental results show that the best effect on the proppant reflux control under high gas injection rate can be obtained when the Changqing ceramsite proppant mesh is 20/40, sanding concentration is 12.6 kg/m², mass ratio of fiber and proppant is more than 0.010 and fiber length is longer than 10 mm. The research results can provide theoretical basis for proppant design and sand control in the injection and production of the fractured wells in low-permeability gas storage.

10.6056/dkyqt202106013