Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on t...Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on the subject, given the emergencies related to climate. An energy transition to clean and renewable sources is necessary and urgent, but it will not be quick. In this sense, increasing the efficiency of oil extraction from existing sources is crucial, to avoid waste and the drilling of new wells. The purpose of this work was to add diffusive and dispersive terms to the Buckley-Leverett equation in order to incorporate extra phenomena in the temporal evolution between the water-oil and oil-water transitions in the pipeline. For this, the modified Buckley-Leverett equation was discretized via essentially weighted non-oscillatory schemes, coupled with a three-stage Runge-Kutta and a fourth-order centered finite difference methods. Then, computational simulations were performed and the results showed that new features emerge in the transitions, when compared to classical simulations. For instance, the dispersive term inhibits the diffusive term, adding oscillations, which indicates that the absorption of the fluid by the porous medium occurs in a non-homogeneous manner. Therefore, based on research such as this, decisions can be made regarding the replacement of the porous medium or the insertion of new components to delay the replacement.展开更多
The X field is located in the southwestern part of block NX89 of Kentan Basin in Libya.This field is produced from Hailan multilayer consolidated sandstone with moderate rock property and a relatively low energy suppl...The X field is located in the southwestern part of block NX89 of Kentan Basin in Libya.This field is produced from Hailan multilayer consolidated sandstone with moderate rock property and a relatively low energy supplying.The reserve of subsurface energy sources is declining with years.Therefore,techniques were combined to achieve the energy optimization and increase hydrocarbon recovery.In order to understand the subsurface formation of the reservoir and facilitate oil production,global hydraulic element technique was used to quantify the reservoir rock types.In addition,stratigraphic modified Lorenz plot was used for reservoir layering.Reservoir heterogeneity was identified using stratigraphic modified Lorenz plot and Dykstra-Parsons coefficient.Leverett J-functionwas used to average the 13 capillary pressure curves into four main curves to represent the whole reservoir based on flow zone indicator values.Capillary pressure was calculated and plotted with normalized water saturation;a single average curve was defined to represent the rest of the curves.Water saturation was calculated using single and multiple J-functions and compared with the available logs.With multiple J-functions,the matching results were good for both high and low-quality layers,whereas using a single J-function,the match was poor,especially for low FZI layers such as H4c and H6a.Four rock types were identified for this reservoir ranging from medium to good reservoir quality and six different layers were obtained.The reservoir was heterogeneous with a Lorenz coefficient value of approximately 0.72 and a Dykstra-Parsons value of 0.70.All approaches used in this paper were validated and showed improved hydrocarbon recovery factor.展开更多
文摘Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on the subject, given the emergencies related to climate. An energy transition to clean and renewable sources is necessary and urgent, but it will not be quick. In this sense, increasing the efficiency of oil extraction from existing sources is crucial, to avoid waste and the drilling of new wells. The purpose of this work was to add diffusive and dispersive terms to the Buckley-Leverett equation in order to incorporate extra phenomena in the temporal evolution between the water-oil and oil-water transitions in the pipeline. For this, the modified Buckley-Leverett equation was discretized via essentially weighted non-oscillatory schemes, coupled with a three-stage Runge-Kutta and a fourth-order centered finite difference methods. Then, computational simulations were performed and the results showed that new features emerge in the transitions, when compared to classical simulations. For instance, the dispersive term inhibits the diffusive term, adding oscillations, which indicates that the absorption of the fluid by the porous medium occurs in a non-homogeneous manner. Therefore, based on research such as this, decisions can be made regarding the replacement of the porous medium or the insertion of new components to delay the replacement.
基金The authors would like to acknowledge the financial support provided by the Universiti Teknologi Malaysia(UTM)under UTM Transdiciplinary Research Grant(Q.J130000.3551.06G68)which made this research effective and viable.
文摘The X field is located in the southwestern part of block NX89 of Kentan Basin in Libya.This field is produced from Hailan multilayer consolidated sandstone with moderate rock property and a relatively low energy supplying.The reserve of subsurface energy sources is declining with years.Therefore,techniques were combined to achieve the energy optimization and increase hydrocarbon recovery.In order to understand the subsurface formation of the reservoir and facilitate oil production,global hydraulic element technique was used to quantify the reservoir rock types.In addition,stratigraphic modified Lorenz plot was used for reservoir layering.Reservoir heterogeneity was identified using stratigraphic modified Lorenz plot and Dykstra-Parsons coefficient.Leverett J-functionwas used to average the 13 capillary pressure curves into four main curves to represent the whole reservoir based on flow zone indicator values.Capillary pressure was calculated and plotted with normalized water saturation;a single average curve was defined to represent the rest of the curves.Water saturation was calculated using single and multiple J-functions and compared with the available logs.With multiple J-functions,the matching results were good for both high and low-quality layers,whereas using a single J-function,the match was poor,especially for low FZI layers such as H4c and H6a.Four rock types were identified for this reservoir ranging from medium to good reservoir quality and six different layers were obtained.The reservoir was heterogeneous with a Lorenz coefficient value of approximately 0.72 and a Dykstra-Parsons value of 0.70.All approaches used in this paper were validated and showed improved hydrocarbon recovery factor.
