Applying Chemical EOR on the Norne Field C-Segment

The world energy demand will grow and oil will continue to be a major part of the energy consumption. Enhanced Oil Recovery will play a key role in meeting the oil demand by increasing the low oil recovery factors in the world today. Half of the oil is still trapped in the reservoir after the production have ceased. The development of new technology has brought a renewed attention for chemical flooding. It has been recognized as a technically feasible method in the Norwegian Continental Shelf and is expected to become attractive. Norne C-Segment is a good candidate for chemical flooding based on screening, current drainage strategy and high water cut. The objects of this Master Thesis are to find an optimum chemical flooding strategy for the Norne C-Segment to maximise the profit from volume of incremental oil produced. The result of the project is based on Net Present Value calculation. Simulations are run in Eclipse on a simulation model of Norne C-Segment released by Center of Integrated Operations at NTNU and Statoil ASA. The model was not perfect history matched therefore an effort to look at the uncertainties in vertical barriers where done before applying chemicals.The Ile formation was chosen as the target formation because of the highest OIP and high oil saturation. A synthetic model of the target formation was build to optimize the chemical injection scheme. Based on the evaluation of the injection wells C-2H was best suited for chemical flooding. The chemicals applied are polymer, surfactant, alkaline and combinations of two or all of these chemicals. Surfactant and alkaline are primarily used to reduce oil-water Interfacial Tension and minimize the capillary forces that trap residual oil after waterflooding. Polymers are used as a mobility control to improve reservoir contact and flood efficiency.Based on the simulation results and economic evaluation polymer flooding is the best chemical flooding method with a net present value of 406 million USD in 2022. Norne C-Segment Ile formation is favourable for mobility control. Surfactant and alkaline cannot mobilize enough residual oil to pay of the cost of chemicals and is not economical attractive.