三元复合驱储层物性变化特征研究

he field tests shows that in the ASP flooding, alkali reacting with reservoir water and mineral can lead to scale and hurt the reservoir and as scaling problems become increasingly serious, production wells work on longer cycle, and the cost of production increases, which have the serious influence on the normal production in oilfield. In this paper, microscopic pore structure differences between cores after water flooding and the ASP flooding and change characteristics on reservoir physical property were studied by scanning electron microscopy and the change of displacement pressure and quantity of displacement liquid particles after the ASP flooding were studied by particle migration experiments. The results showed that alkali can dissolute formation rock minerals forming a large number of mud and tiny particles. The corrosion damage is more noticeable that the displacement agent of the ASP flooding have to the formation; dissolution of feldspar, quartz and clay mineral is more serious, and pore filling with granular material, and mineral surface has small pieces of secondary quartz, which prevent the process of oil displacement. The study on change characteristics of reservoir physical property after the ASP flooding provides the basis for scaling mechanism after the ASP flooding and it is necessary for improving recovery after the ASP flooding.