钻探工程2025，Vol.52Issue(2)：125-133,9.DOI:10.12143/j.ztgc.2025.02.017
PVA改性PLA纤维复合地热暂堵水泥的研制及性能表征
Development and performance characterization of PVA modified PLA fiber composite geothermal temporary sealing cement
摘要
Abstract
Formations with developed fractures are more likely to receive better water supply,and severe leakage during drilling requires the use of cement for sealing,but this can easily cause reservoir damage problems.In this paper,a geothermal temporary plugging cement is developed based on degradable fibers,which has a low permeability during drilling,plays the role of wall protection and plugging,and partially degrades to provide a channel for the output of geothermal fluids after the completion of the well.Based on the preparation,modification and characterization of PVA-coated PLA fibers(PVA-PLA),the effects of the modified fibers on the performance of the cement paste and the performance of cemented cement stone before and after high-temperature hot-water immersion were investigated and the mechanism was analyzed.The results showed that:the regulation of the degradation properties of polymer fibers can be achieved by coating,heat treatment and silane modification;the compressive strength of PVA-PLA fiber cementite at 60℃was 19.8MPa at maximum,and the porosity was 28.88%at maximum after immersion at 90℃,which was most in line with the requirements of low-temperature plugging and high-temperature unplugging;the coating of PVA at 60℃reduced the contact between PLA and cement matrix,and the PVA-PLA fiber cementite at 90℃was more suitable to the requirements of low-temperature plugging and high-temperature unplugging.The PVA membrane dissolved and PLA exposed to cement alkaline environment was hydrolyzed and consumed during hot water immersion at 90℃,which resulted in the formation of more pores larger than 200nm in the cement stone.The PVA-PLA fibers remain intact and plug with the cement stone at low temperature,and the fiber degradation at high temperature forms a channel inside the cement stone and unblocking,which can support the broken pore wall and at the same time,realize partial unblocking of geothermal wells under high temperature hydrothermal conditions.关键词
暂堵水泥/改性纤维/PVA/PLA/高温降解/孔径分布/地热井Key words
temporary sealing cement/modified fibers/PVA/PLA/high temperature degradation/pore size distribution/geothermal well分类
天文与地球科学引用本文复制引用
崔曦月,谭慧静,陈瑶,郑云天,王宇昊,叶有..PVA改性PLA纤维复合地热暂堵水泥的研制及性能表征[J].钻探工程,2025,52(2):125-133,9.基金项目
国家自然科学基金青年科学基金项目"基于温敏聚合物的地热井暂堵型高透水固结材料研究"(编号:41902322) （编号:41902322）
四川省科技计划资助项目(编号:2023NSFSC0781) （编号:2023NSFSC0781）
