石油钻采工艺2026，Vol.48Issue(3)：333-342,10.DOI:10.13639/j.odpt.202601004
基于核磁共振T2谱的致密砾岩储层纳米乳液-CO2吞吐孔喉尺度动用特征
Study on the pore-throat scale mobilization characteristics of nano emulsion-CO2 flooding in tight conglomerate reservoirs based on NMR T2 spectrum
摘要
Abstract
To address the challenges associated with tight conglomerate reservoirs,including complex pore throat structures,poor mobilization of crude oil in micropores,and rapid production decline in conventional huff-and-puff development,this study investigates the synergistic effects of nano-emulsion and supercritical CO2(SC-CO2)huff-and-puff on oil mobilization in multi-scale pore throats.Tight conglomerate core samples from the same reservoir interval were selected.High-pressure mercury intrusion and nuclear magnetic resonance(NMR)T2 spectrum were combined to calibrate the pore-throat structures.Comparative experiments were then carried out,including depletion development,multiple cycles of nano-emulsion and formation water huff-and-puff,followed by SC-CO2 huff-and-puff.By continuously monitoring the changes in NMR T2 spectra throughout the entire cycle,the fluid mobilization efficiency and recovery contribution in different pore-size ranges>10μm were quantitatively analyzed.During the depletion stage,oil is mainly produced from medium-large pores(>1 μm)with sound hydraulic communication,while the recovery from micropores is lower than 15%,resulting in an overall recovery of 11%-12%only.Nano-emulsion huff-and-puff improves the mobilization efficiency in 0.1-10 μm pore-throat range by approximately 5%-25%compared with formation water,and the overall recovery reaches 53%after three cycles.Subsequent SC-CO2 huff-and-puff further enhances oil mobilization across all pore throat sizes,with particularly significant effects in micropores and large pores.After three cycles,the overall mobilization efficiency approaches 90%,which is about 14%higher than that of pre-treatment with formation-water.The results indicate that nano-emulsion pre-huff-and-puff combining with subsequent SC-CO2 huff-and-puff exhibits favorable compatibility,which promotes the further mobilization of residual oil from large pores to micropores,and increases the overall recovery by 67%.This combined approach therefore has positive implications for improving crude oil mobilization in the micropores of tight conglomerate reservoirs.关键词
致密砾岩储层/纳米乳液吞吐/超临界CO2吞吐/核磁共振T2谱/孔喉动用/协同增效Key words
tight conglomerate reservoir/nanometer emulsion flooding/supercritical CO2 huff-n-puff/NMR T2 spectra/pore-throat mobilization/synergistic enhancement分类
能源科技引用本文复制引用
汤传意,田冷,李卫华,徐文熙,田辉,曲长友,祁壮壮,张旭..基于核磁共振T2谱的致密砾岩储层纳米乳液-CO2吞吐孔喉尺度动用特征[J].石油钻采工艺,2026,48(3):333-342,10.基金项目
国家科技重大专项"CO2促混转混综合调控技术研究"(编号:2024ZD1406601). （编号:2024ZD1406601）
