多元热流体吞吐开发稠油乳状液稳定性机理

Stability mechanism of heavy oil emulsion during cyclic multi-thermal fluids injection process

稠油在全球能源格局中占据重要地位,在满足全球不断增长的能源需求方面发挥着重要作用。多元热流体(超临界蒸气、CO_(2)和N_(2))吞吐开发技术能够克服传统蒸气驱能耗高、热利用率低、效果差的问题,已成为提高稠油采收率的前景技术。然而,稠油中的表面活性物质及多元热流体的复杂组分会导致多元热流体吞吐过程中形成稳定且复杂的乳状液,为后续稠油破乳工作带来了巨大挑战。首先通过分析稠油族组分含量、沥青质微观形貌及官能团特性,明确了稠油基本物性。随后,基于含水率、乳状液粒径尺寸分布等参数,探讨了多元热流体吞吐开发稠油乳状液稳定性,并利用扫描电镜和红外光谱技术揭示了乳状液稳定性机制。最终,研究了聚醚型破乳剂对稠油乳状液的脱水效果。为针对多元热流体吞吐技术的高效破乳剂研发提供了理论指导。

Heavy oil holds a pivotal position in the global energy landscape and plays a significant role in meeting the increasing energy demand worldwide.The utilization of multi-thermal fluids(comprising supercritical steam,CO_(2),and N_(2))in cyclic solvent injection(CSI)techniques overcomes the challenges associated with conventional steam flooding techniques such as high energy consumption,low heat utilization and poor performance,and becomes a promising technique for enhancing heavy oil recovery.However,the presence of surface-active substances in heavy oil and the complex composition of multi-thermal fluids leads to the formation of complex and stable emulsions during the cyclic multi-thermal fluids injection process,which poses challenges to subsequent demulsification.This study first elucidates the properties of heavy oil based on heavy oil component analysis,microscopic examination of asphaltene morphology and functional groups.Subsequently,the stability of emulsion generated during the cyclic multi-thermal fluids injection process is investigated based on water segmented ratio and particle size distribution of emulsion droplets.Furthermore,the stability mechanisms of emulsion are studied using scanning electron microscopy and infrared spectroscopy techniques.Finally,the effect of the polyether-type demulsifier on facilitating the dehydration of heavy oil emulsion is evaluated.The findings of this research provide theoretical insights to guide the development of efficient demulsifiers for cyclic multi-thermal fluid injection process.