低渗-特低渗储层微观水驱油特征及其影响因素

Characteristics and influence factors for oil displacement efficiency by the micro-model water flooding experiment in low permeability-ultra low permeability reservoir

通过鄂尔多斯盆地延长组低渗-特低渗透砂岩微观模型水驱油实验,总结微观水驱油特征,探讨微观水驱油驱油效率的影响因素。研究发现,低渗-特低渗透砂岩储层水驱油过程中,水驱油特征主要表现为:驱油方式主要以非活塞式驱替为主;残余油主要以绕流残余油为主;非均质性越强,驱油效率越低;原油黏度越低,驱油效率越高;驱替速度不同,驱油效率不同;通道类型不同,去提效率不同;影响因素包括:物性;孔隙结构非均质性;微观孔隙结构;水驱倍数;驱替压力和开采方式。低渗-特低渗透砂岩储层水驱开发中影响开发效果的因素较多,但是主控因素是微观孔隙结构和非均质性。因此对于低渗-特低渗透砂岩储层水驱开发,应选择合理的工艺参数和具有针对性的改善水驱开发效果措施,才能保证较好的开发效果。

By the sandstone micro-model water flooding experiment of low permeability -ultra low permeability sandstone reservoir in the Ordos basin.Summarizing the characteristics of microscopic water flooding,to investigate the factors affecting water displacing oil dis- placement efficiency in this paper.It＇s discovered that the low permeability-ultra low perme- ability sandstone reservoir water flooding process.Water flooding main characteristics,flooding in major non-piston displacement based.Residual oil to flow around the main residual oil-based,stronger heterogeneity,the lower the oil displacement efficiency.Viscosity of crude oil by the end of the higher oil displacement efficiency,displacement velocity different,different oil displacement efficiency.Channel types,different to mention efficiency.Influence factors in-clude,physical properties,pore structure heterogeneity,microscopic pore structure,water flood- ing multiples,displacement pressure and mining methods.So for low permeability-ultra low permeability sandstone reservoir water flooding should choose reasonable parameters and targeted measures to improve water flooding effect,in order to ensure better development resuits.