低密度陶粒支撑剂的水敏老化机理研究  

Water-Sensitive Aging Mechanism of Low-Density Ceramic Proppant

作　　者：陈佳宁 郝建英[1] 王升昌 梁天成[2,3] CHEN Jianing;HAO Jianying;WANG Shengchang;LIANG Tiancheng(School of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China;PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;CNPC Key Laboratory of Oil&Gas Reservoir Stimulation,Langfang 065007,China)

机构地区：[1]太原科技大学材料科学与工程学院,太原030024 [2]中国石油勘探开发研究院,北京100083 [3]中国石油天然气集团有限公司油气藏改造重点实验室,廊坊065007

出　　处：《硅酸盐通报》2023年第9期3334-3341,共8页Bulletin of the Chinese Ceramic Society

基　　金：山西省基础研究计划(202203021211186);山西省重点研发项目(201903D121101);中国石油前瞻性基础工程项目(2021DJ1805)。

摘　　要：低密度陶粒支撑剂良好的性能在非常规能源开采工作中显得十分重要。针对低密度陶粒支撑剂在地层水服役期间性能退化的现象,本文选取两种不同规格的支撑剂,在地层水中浸泡不同时间后取出,采用XRF、XPS、XRD、SEM、TEM对浸泡前后的支撑剂进行表征,探索支撑剂老化机理。结果显示:支撑剂中ClO_(2)含量增加,Al2O_(3)、SiO_(2)含量减少,地层水中Cl^(-)、HCO_(3)^(-)含量减少;XPS检测出Cl 2p峰和Cl 2s峰;XRD检测出新相SiCl_(4)。以上结果证实,地层水中的Cl^(-)扩散到支撑剂表面与SiO_(2)反应生成SiCl_(4),SiCl_(4)进一步水化生成硅凝胶或硅酸凝胶包覆在支撑剂表面。支撑剂中Al_(2)O_(3)会与地层水中H^(+)(酸性环境)反应生成Al^(3+),Al^(3+)再与HCO_(3)^(-)反应生成Al(OH)_(3)沉淀进入地层水中。地层水中大量的Cl^(-)和H^(+)共同作用,使支撑剂从表面开始侵蚀,导致支撑剂内部结构致密化程度降低,结构松散,从而使支撑剂的抗破碎能力降低,性能退化。Good performance of low-density ceramic proppant is particularly important during the exploration of unconventional energy.In view of the performance degradation of low-density ceramic proppant upon serving in the formation water,two specifications of proppant were selected to be soaked in the formation water for different time.The proppant before and after soaking was characterized by XRF,XPS,XRD,SEM and TEM,and its aging mechanism was explored.The results show that the content of ClO_(2) in the proppant increases,while the content of Al_(2)O_(3) and SiO_(2) decreases,and the content of Cl^(-)and HCO_(3)^(-) in the formation water decreases.The peaks of Cl 2p and Cl 2s appear by XPS,and the new phase SiCl4 is detected by XRD.These results confirm that Cl^(-)in the formation water diffuses to the proppant surface and reacts with SiO_(2) to form SiCl_(4),which further hydrates to generate silicone gel or silicic acid gel and coats the proppant surface.Al_(2)O_(3) in the proppant can react with H+(acidic environment)of the formation water to form Al^(3+),and then Al^(3+)reacts with HCO_(3)^(-) to form Al(OH)_(3) precipitating into the formation water.A large amount of Cl^(-)and H^(+)in the formation water erode the proppant from the surface,reducing the densification within the structure and making the structure loose,which reduces the proppant crushing resistance and degrades its performance.

关 键 词：低密度陶粒支撑剂 地层水 硅凝胶 老化机理 Cl^(-)侵蚀 酸性环境 

分 类 号：TQ174.1[化学工程—陶瓷工业]