Experimental Investigation of Secondary Oil Recovery in Fractured Media

Naturally fractured reservoirs (NFRs) contribute in large extent of oil and gas production to the ever increasing market demand of fossil energy. It is believed that waterflooding can more than double the recoverable reserves of many developed oilfields especially the fractured ones at low capital investment. Hence, as the methodological plan of this study, unconsolidated packed models of cylindrical geometry surrounded by fractures are utilized in order to perform a series of flow visualization experiments during which the contribution of different parameters such as the extent of matrix wettability (water-wet, oil-wet, fractional wet and mixed wet), absolute permeability, and the physical oil properties (e.g., density, and viscosity) is studied. The results show that the recovery efficiency from water-wet media is higher than other cases. Furthermore, by decreasing the model permeability and increasing the oil viscosity during secondary recovery process, the recovery efficiency reduces