Curing kinetics and plugging mechanism of high strength curable resin plugging material  

作　　者：Jing-Bin Yang Ying-Rui Bai Jin-Sheng Sun Kai-He Lv 

机构地区：[1]School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,266580,Shandong,China [2]CNPC Engineering Technology R&D Company Limited,Beijing,102206,China

出　　处：《Petroleum Science》2024年第5期3446-3463,共18页石油科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Grant 52374023, 52288101);Taishan Scholar Young Expert (Grant tsqn202306117)。

摘　　要：Lost circulation, a recurring peril during drilling operations, entails substantial loss of drilling fluid and dire consequences upon its infiltration into the formation. As drilling depth escalates, the formation temperature and pressure intensify, imposing exacting demands on plug materials. In this study, a kind of controllable curing resin with dense cross-network structure was prepared by the method of solution stepwise ring-opening polymerization. The resin plugging material investigated in this study is a continuous phase material that offers effortless injection, robust filling capabilities, exceptional retention, and underground curing or crosslinking with high strength. Its versatility is not constrained by fracture-cavity lose channels, making it suitable for fulfilling the essential needs of various fracture-cavity combinations when plugging fracture-cavity carbonate rocks. Notably, the curing duration can be fine-tuned within the span of 3-7 h, catering to the plugging of drilling fluid losing of diverse fracture dimensions. Experimental scrutiny encompassed the rheological properties and curing behavior of the resin plugging system, unraveling the intricacies of the curing process and establishing a cogent kinetic model. The experimental results show that the urea-formaldehyde resin plugging material has a tight chain or network structure. When the concentration of the urea-formaldehyde resin plugging system solution remains below 30%, the viscosity clocks in at a meager 10 mPa·s. Optimum curing transpires at 60℃, showcasing impressive resilience to saline conditions. Remarkably, when immersed in a composite saltwater environment containing 50000 mg/L NaCl and 100000 mg/L CaCl_(2), the urea-formaldehyde resin consolidates into an even more compact network structure, culminating in an outstanding compressive strength of 41.5 MPa. Through resolving the correlation between conversion and the apparent activation energy of the non-isothermal DSC curing reaction parameters, the study attests to the ful

关 键 词：Urea-formaldehyde resin Rheological property Curing property Curing kinetics Plugging mechanism 

分 类 号：TE28[石油与天然气工程—油气井工程]