环境友好型高成球产率自生支撑剂的构筑与性能

Construction and Performance of Environmentally Friendly Self-generated Proppants with High Microsphere Formation Yield

吴绍伟 尹金容 李真勇 曾真 许敏 任先艳

WU Shaowei YIN Jinrong LI Zhenyong ZENG Zhen XU Min REN Xianyan

为了避免使用有机溶剂、改善自生支撑剂在井下生长过程中易粘并团聚的问题，采用苯乙烯（St）和二乙烯 基苯（DVB）作为可相变组分、含分散剂的水溶液作为不可相变组分，设计了一种环境友好型自生支撑剂。通过 调控不可相变组分中分散剂的组成和用量及两组分的预混合搅拌转速等方法，确定自生支撑剂的最佳配方及制 备工艺。通过扫描电子显微镜、X射线衍射分析、红外光谱分析了自生支撑剂的形貌与结构，通过颗粒强度测定 仪、恒载试验机等评价了自生支撑剂的性能。结果表明，两组分的预混合转速为120 r/min。不可相变组分中的 分散剂为聚乙烯醇-1788、甲基纤维素、十二烷基苯磺酸钠（质量比为5000∶175∶2）。在模拟裂缝温度为100 ℃且 完全静置反应的条件下，自生支撑剂的液-固相变时间范围为32.5～40.0 min，相变后约24 min 时完成强度的快 速增长。自生支撑剂单颗粒分散微球的产率可达78%，且可控制60%的微球尺寸分布于0.850～0.425 mm（20～ 40 目）。自生支撑剂微球单颗粒强度极大值约32 N，视密度约1.18 g/cm3 ，球形度高于0.9，酸溶解度低至2.47%。 自生支撑剂微球的单颗粒强度与市售陶粒支撑剂相当，显著高于市售石英砂支撑剂；其耐酸性显著高于市售陶 粒和石英砂支撑剂。提出的自生支撑剂体系和制备方法改善了自生支撑剂流体在缺失剪切力辅助作用下易团 聚、产率低、成球率低的难题，且不需添加有机溶剂、环境友好，具有深部储层开采的极大潜力。

To avoid the use of organic solvents and improve the problem of self-generated proppants easy to aggregate during growth in the well，an environmentally friendly self-generated proppant was designed using styrene（St）and divinylbenzene （DVB）as phase change component，and aqueous solution containing dispersants as non-phase change one. By adjusting the composition and dosage of dispersants in non-phase change component and the speed of pre-mixing of the two phases，the optimum formula and preparation process of self-generated proppant were determined. The morphology and structure of self-generated proppant were analyzed by scanning electron microscope，X-ray diffraction analysis and infrared spectroscopy. Furthermore，its performances were evaluated by particle strength tester and constant load tester. The results showed that，the pre-mixing speed of the two phases was determined to 120 r/min. The dispersants in non-phase change component was polyvinyl alcohol-1788， methylcellulose and sodium dodecyl benzene sulfonate in mass ratio of 5000∶175∶2. When the reaction was standing at a simulation fractures temperature of 100 ℃，the liquid-solid phase transition time of self-generated proppant was 32.5—40.0 min，and then the rapid increase in strength was achieved about 24 min after the phase transformation. The yield of single particle dispersed proppant could reach 78%. Meanwhile，the size of 60% proppant particles could be controlled in 0.850—0.425 mm（20—40 mesh）. The self-generated proppant particles had maximum single particle strength about 32 N，an apparent density of about 1.18 g/cm3，a degree of sphericity of about 0.9 and a low acid solubility of 2.47%. The single particle strength of self-generated proppant was comparable to that of commercially available ceramic proppant，while significantly higher than that of quartz sand proppant. Its acid resistance was significantly higher than that of both. The proposed self-generated proppant and its construction method improved the problems of easy aggregation，low yield and low microsphere formation yield of the self-generated proppant under the absence of shear force. Furthermore，the phase-change solution here did not need to add any organic solvents and is environmentally friendly. It had great potential for deep reservoir exploitation.

10.19346/j.cnki.1000-4092.2024.02.004