AbstractThis research thesis aimed at investigating the application of relative permeability modification treatment on the Zaafarana Field in the Gulf of Suez. The objective was to build a full study that covers the technical and commercial aspects of the application. The research commenced with a comprehensive literature review that provided the backbone to the work carried out. The literature review covers aspects of reservoir permeability and relative permeability, the dynamics of water-oil displacement, problems of oil fields increased water production and the different available solutions. It then moves to the concept of Relative Permeability Modification (RPM), the prediction techniques, mechanism within the porous media, previous experience, candidate selection indicators and finally its process modelling.
To allow a good understanding of the selected field case, the next part of the research provides background on the Gulf of Suez and the Zaafarana Field. A review is provided of the geological and reservoir characteristics of the field, its development and facilities, its production history, leading to the reasons for the high water production problem in the field. A detailed description is also provided of the Zaafarana static model structure and building parameters. The Zaafarana dynamic model build steps are detailed until a complete history matched model was created.
The next part of the work moved towards describing the modelling methods attempted for modifying the relative permeability which is the main focus of the research and the success achieved through applying the unique flexible restart with Relative Permeability to Water (KRW) reduction method. This method was used with multiple reduction sensitivities on both a single well and at full field scale. The relative permeability to water was reduced by 10, 20, 30, 40 and 50% in the single well modification case. An additional sensitivity of 60% reduction was also modelled on the full field case. The change to KRW was applied in the perforation zones of each well. Overall, the oil ultimate recovery (EUR) is improved in all the wells and across all the reduction scenarios. There was an immediate change in terms of the oil rate increasing and water rate and water cut decreasing. The oil rates were increased by 2% to 51% in the first 3 months post treatment for the 10% to 60% modifications respectively. The oil and water rates returned to the pre-treatment rates within 4-18 months in the different scenarios.
Additional sensitivities were modelled on the single well modification, whereby the change to KRW was extended to cells beyond the perforation interval; however, this had little impact in terms of additional oil recovery.
To complement the technical achievements with the commercial requirements and to be able to evaluate the technical improvements in terms of Reserves and economic indicators, a cost estimate study and analysis was performed and an economic model was constructed. The resulting production and Capital and Operating Expenditure (CAPEX and OPEX) profiles were included in the economic analysis which provided the improvements in Reserves and Net Present Values (NPVs).
A sensitivity on the mid case was included in the economic analysis, which assumed that the treatment will be repeated every three years. This is supported by the two facts; that it’s a low cost treatment (approximately US$412.5K per well) and that the improvement lasts under 2 years.
|Date of Award||May 2019|
|Supervisor||Mohamed Hassan Sayed (Supervisor), Richard Wheaton (Supervisor) & David Sanders (Supervisor)|