Experimental and Modeling Investigation of Low Salinity Water Flooding in some Oil fields of Republic of Kazakhstan – Improved Oil Recovery Implications

Faculty Development Competitive Research Grant Program 2019-2021

Low Salinity Water (LSW) also known as smart water flooding can be injected into oil reservoirs economically with the potential of improved oil recovery (IOR) which is known as Low Salinity Water Flooding (LSWF). In recent years, it has been observed that the injection of low salinity water in oil reservoirs (both sandstone and limestone) causes an incremental recovery from the Original Oil In Place (OOIP) and increases the ultimate oil recovery from the target reservoirs. Various theories were proposed to explain the improvement in oil recovery. However, there is not sufficient consensus on what is considered the principal mechanisms behind the low salinity effect. It is a fact that the recovery is due to the chemical composition of injected water and mineralogical characteristics of the formation. The interaction of these systems is still being debated in the literature and constitutes an active area of research. A comprehensive experimental measurements will be performed to explore the interaction between brine, oil and rock systems under different salinities, ion types and clay contents designed based on the targeted reservoir conditions. The experiments will include the wettability and IFT measurements, and also the investigation of potential scaling and fine migration under different test conditions. The results of these experiments will help to better understand the mechanisms contributing towards the enhanced oil recovery by LSW. A series of coreflood experiments will also be carried out using both synthetic brines and formation water and oil from the oil fields to investigate the performance of LSWF at real reservoir dynamics conditions. Later on, a reliable model will also be developed and suggested using ECLIPSE software based on the actual mechanisms happening during LSWF. The experimental results will be used to verify the model and different reasonable LSWF scenarios will be investigated. In addition, the verified model will be used to run a comprehensive sensitivity analysis to propose an optimized LSW injection strategy for the targeted oil field. The output of the project will help to economically improve the oil recovery in the secondary oil recovery staged through applying the cost-effective LSWF-EOR primarily designed for the oil fields investigated from Republic of Kazakhstan. However, the results can be used in any petroleum reservoirs in other jurisdictions provide there is some analogy between the reservoir rock and fluid properties in addition to the reservoir conditions.