Abstract
Thermal oil recovery techniques, including steam processes, account for more than 80% of the current global heavy oil, extra heavy oil, and bitumen production. Evaluation of Naturally Fractured Carbonate Reservoirs (NFCRs) for thermal heavy oil recovery using field pilot tests and exhaustive numerical and analytical modeling is expensive, complex, and personnel-intensive. Robust statistical models have not yet been proposed to predict cumulative steam to oil ratio (CSOR) and recovery factor (RF) during steamflooding in NFCRs as strong process performance indicators. In this paper, new statistical based techniques were developed using multivariable regression analysis for quick estimation of CSOR and RF in NFCRs subjected to steamflooding. The proposed data based models include vital parameters such as in situ fluid and reservoir properties. The data used are taken from experimental studies and rare field trials of vertical well steamflooding pilots in heavy oil NFCRs reported in the literature. The models show an average error of <6% for the worst cases and contain fewer empirical constants compared with existing correlations developed originally for oil sands. The interactions between the parameters were considered indicating that the initial oil saturation and oil viscosity are the most important predictive factors. The proposed models were successfully predicted CSOR and RF for two heavy oil NFCRs. Results of this study can be used for feasibility assessment of steamflooding in NFCRs
Highlights
Consumption of liquid fuels, from both conventional and unconventional resources, will continue to be the primary source of energy in the decades to come
This conveys the message that these figures just present a limited volume of data used in this study to point out the important trends in performance of reservoirs during steamflooding according to a comprehensive parametric sensitivity analysis
The proposed linear regressions are valid for cumulative steam to oil ratio (CSOR) and Recovery Factor (RF) in terms of the particular dependent variables shown on x-axis. These results show that CSOR values for viscous oil extraction from Naturally Fractured Carbonate Reservoirs (NFCRs) and some highly naturally fractured sandstone reservoirs can be correlated with reservoir and oil characteristics such as permeability, porosity, thickness, viscosity, and oil saturation
Summary
Consumption of liquid fuels, from both conventional and unconventional resources, will continue to be the primary source of energy in the decades to come. Agency (IEA) in their World Energy Outlook 2015 report and some other reports from the U.S. Energy Information Administration (EIA) [1,2,3], global demand for oil is expected to grow from. Energies 2018, 11, 292 global daily production rate is 96.5 × 106 b/d This is mostly due to expected world population growth combined with increasing per capita demand in growing economies such as China and India. To meet the demand for liquid fuels in 2030, additional production of 6.5 × 106 b/d [1 × 106 m3 ] will be needed This is just a modest forecast as a reference scenario from the IEA and depending to the world economic conditions and other factors affecting the oil price and fuel consumption rate this figure is subject to change. The actual demand for oil could clearly be higher [1,2,3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
