Efficient Simulation for Low Salinity Waterflooding in Porous and Fractured Reservoirs
Low-salinity brine injection has emerged as a promising, cost-effective improved oil recovery (IOR)method for waterflooding reservoirs. Laboratory tests and field applications show that low-salinity waterflooding could lead to significant reduction of residual oil saturation. There has been a growing interest with an increasing number of low-salinity waterflooding studies. However, there are few quantitative studies on flow and transport behavior of low-salinity IOR processes. This paper presents a general mathematic model (1) to incorporate known IOR mechanisms and (2) to quantify low-salinity waterflooding processes. In our mathematical conceptual model, salt is treated as an additional “component” to the aqueous phase, based on the following physical considerations: salt is transported only within the aqueous phase by advection and diffusion, and also subject to adsorption onto rock solids; relative permeability, capillary pressure, and residual oil saturation depend on salinity. Interaction of salt between mobile and immobile water zones is handled rigorously using a multi-domain approach. Fractured rock is handled using the multiple-continuum model or a discrete-fracture modeling approach. The conceptual model is implemented into a general-purpose reservoir simulator for modeling low-salinity IOR processes, using unstructured, regular, and irregular grids, applicable to 1-D, 2-D, and 3-D simulation of low-salinity water injection into porous media and fractured reservoirs. As demonstrated, the model provides a general capability for quantitative evaluation of low-salinity waterflooding in site-specific investigations.
Y. Wu and B. Bai, "Efficient Simulation for Low Salinity Waterflooding in Porous and Fractured Reservoirs," SPE Reservoir Simulation Symposium, Society of Petroleum Engineers (SPE), Feb 2009.
The definitive version is available at http://dx.doi.org/10.2118/118830-MS
Geosciences and Geological and Petroleum Engineering
Keywords and Phrases
Low-Salinity Brine Injection; Oil Recovery Method; Waterflooding Reservoirs
Article - Conference proceedings
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