深层煤岩压裂液稠化剂吸附损害机理与控制对策  

Adsorption damage mechanism and control of fracturing fluid thickener in deep coal rock

作　　者：游利军[1] 钱锐 康毅力[1] 王艺钧 YOU Lijun;QIAN Rui;KANG Yii;WANG Yijun(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]西南石油大学油气藏地质及开发工程全国重点实验室,成都610500

出　　处：《石油勘探与开发》2025年第1期185-193,共9页Petroleum Exploration and Development

基　　金：国家自然科学基金项目“富有机质页岩氧化致裂增渗加速气体传输机理研究”(51674209);非常规油气层保护四川省青年科技创新研究团队项目“页岩/煤岩气层氧化协同水力压裂减量增渗方法研究”(2021JDTD0017)。

摘　　要：选取鄂尔多斯盆地石炭系本溪组典型8~#深层煤岩开展静态吸附和动态损害实验,评价压裂液稠化剂羟丙基胍胶和聚丙烯酰胺在深层煤岩表面的吸附量和吸附引起的渗透率损害;采用原子力显微镜定量表征稠化剂的吸附形貌,分析稠化剂吸附的主要控制因素,同时采用Zeta电位、傅里叶红外光谱、X射线光电子能谱等技术揭示稠化剂的吸附机理。研究表明:实验条件下,深层煤岩对羟丙基胍胶、聚丙烯酰胺的吸附量分别为3.86mg/g和3.29mg/g,吸附后煤岩渗透率分别下降35.24%~37.01%和14.31%~21.93%;压裂液稠化剂吸附层厚度与稠化剂质量分数正相关,与温度负相关,pH值降低将减小羟丙基胍胶吸附层厚度、使聚丙烯酰胺吸附层厚度分布频率更集中;官能团缩聚、分子间作用力是深层煤岩吸附压裂液稠化剂的化学和物理作用力。通过优化稠化剂质量分数、对稠化剂分子进行化学改性、对聚合物进行氧化生热降解、添加解吸附剂等方法可降低煤岩微纳米级孔隙、裂缝的损害风险。Static adsorption and dynamic damage experiments were carried out on typical 8#deep coal rock of the Carboniferous Benxi Formation in the Ordos Basin to evaluate the adsorption capacity of hydroxypropyl guar gum and polyacrylamide as fracturing fluid thickeners on deep coal rock surface and the permeability damage caused by adsorption.The adsorption morphology of the thickener was quantitatively characterized by atomic force microscopy,and the main controlling factors of the thickener adsorption were analyzed.Meanwhile,the adsorption mechanism of the thickener was revealed by Zeta potential,Fourier infrared spectroscopy and X-ray photoelectron spectroscopy.The results show that the adsorption capacity of hydroxypropyl guar gum on deep coal surface is 3.86 mg/g,and the permeability of coal rock after adsorption decreases by 35.24%–37.01%.The adsorption capacity of polyacrylamide is 3.29 mg/g,and the permeability of coal rock after adsorption decreases by 14.31%–21.93%.The thickness of the thickener adsorption layer is positively correlated with the mass fraction of thickener and negatively correlated with temperature,and a decrease in pH will reduce the thickness of the hydroxypropyl guar gum adsorption layer and make the distribution frequency of the thickness of polyacrylamide adsorption layer more concentrated.Functional group condensation and intermolecular force are chemical and physical forces for adsorbing fracturing fluid thickener in deep coal rock.Optimization of thickener mass fraction,chemical modification of thickener molecular,oxidative thermal degradation of polymer and addition of desorption agent can reduce the potential damages on micro-nano pores and cracks in coal rock.

关 键 词：深层煤岩气 压裂液 稠化剂 吸附形貌 吸附机理 控制因素 渗透率损害 损害预防 

分 类 号：TE371[石油与天然气工程—油气田开发工程]