Nanotechnology EOR - Formation of Linked Polymer Solutions at NCS conditions

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In order to fulfil the ambitious targets set for oil recovery on the Norwegian continental shelf (NCS) it is necessary to implement enhanced oil recovery (EOR) methods. Most of the Norwegian fields are developed with water flooding and are therefore good candidates for EOR. Linked polymer solutions (LPS) is an enhanced oil recovery (EOR) method that improves microscopic sweep efficiency and reduce oil saturation by microscopic diversion. Field results from onshore fields in China show up to 20 % increase in recovery and recent core flood studies performed at CIPR indicate a huge potential for NCS reservoirs. StatoilHydro is planning an injection test for LPS at the Heidrun field in 2010. In order to implement LPS on the NCS it necessary to improve our und erstanding of the underlying mechanism of microscopic diversion. In this research project we will focus on improving the understanding of LPS mechanism by investigating the physico-chemical properties of LPS. In particular the influence of reservoir cond itions such as salinity and temperature and how changes in LPS properties can be mitigated by changes in the LPS formulation. The LPS system consists of a polymer and a crosslinker. The concentration of each component and the ratio between them will deter mine whether the reaction generates predominantly intra-molecular interactions giving free solvated polymer or coiled polymer particles or inter-molecular interactions forming polymer gels. The hypothesis for LPS mechanism require coiled polymer particles to be formed and it is a key objective to determine boundary conditions or phase windows for coiled particles at various conditions. Additionally, the kinetics of the reaction will be determined as this is an important parameter for designing field imple mentation and topside residence times. The deliverables from this project will be an improved understanding of the LPS system which can optimise LPS flood performance and accelerate implementation.