In industrial applications such as hydraulic water fracking, polymers are added at dilute concentrations to the flow causing significant drag reduction (DR) and leading to a massive reduction to pump energy cost. In recent years, an alternative approach that is based on rotational flow has shown capabilities of measuring DR based purely on rheological testing. Nonetheless, there are some limiting assumptions in this approach that can lead to inaccurate interpretation of the data, especially for non-Newtonian polymer solutions, where the Reynolds number (Re) is evaluated at the infinite-shear or solvent viscosities. However, it is well known that the apparent viscosity of the polymer solutions is higher than that of a solvent at a stable region and lower than infinite shear viscosity at an unstable one. In this study, we propose a theoretical form of the DR expression that is based on the Re, which is estimated at the apparent local viscosity measure. The work establishes a promising approach for screening DR agents using rheological measurements. Moreover, the study presents new theoretical findings and analyses for estimating DR and extrapolating the results to high Re. Two polymer solutions of xanthan gum (XG) and partially hydrolyzed polyacrylamide (HPAM) in distilled water are tested at concentrations between 5 and 150 ppm using a concentric double-gap cylinder. The proposed approach is found to be more consistent with the theory of linear flow (i.e., flow loop), where the DR in the stable region is found to be identically zero. The transition from stable to unstable regions is also consistent with the existing linear flow theory. This enhances the role of rheological testing for DR measurements and DR agent screening, which provides a platform for the application of simple and cost-effective rheometry in the DR industry.

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To make proper utilization of natural resources, we try to explore the enhanced oil recovery (EOR) potential of the date leaf as the date tree is available all over the Saudi Arab as well as the Middle East. The aims of the study are to develop carbon nanoparticle from green Date-leaf and apply in EOR process. Date-leaf carbon micro-nanostructured particles (DLCMNPs) were prepared from date leaves using pyrolysis method. After that, carboxylic acid functionalization was performed by acid treatment to make water soluble. Finally, morphological and chemical compositional characterizations of the DLCMNPs were done. Interfacial tension (IFT) between Arab light crude oil and DLCMNPs was measured using ASTM D 971-99a method [1] to find out the critical micelle concentration (CMC) and do core flood experiment. Field Emission Scanning Electron Microscopic (FESEM) images revealed that the carbon particles are in the range of few μm to 20 μm and are micro-nanostructured (i.e the micro-particles composed from nanosheets). The Energy Dispersive Spectroscopy (EDS) indicates the presence of oxygen and little amount of silicon in addition to carbon in the particles. The TEM images indicated that the particles are porous in nature and contain nanosheets which correlate the findings of FESEM study. The selected area diffraction (SAED) pattern showed that the particles are crystalline in nature. XPS analysis of the DLCMNPs found that the presence of Si, C and O which was similar to the observation of EDS analysis. It also confirmed that the DLCMNPs is carboxylated functionalized. IFT between Arab Light crude oil and different concentrations of DLCMNPs solutions with distilled water were measured to determine the CMC. It was found that the particle has the capability to reduce IFT significantly. Core flood are going to conduct to explore the oil recovery potential. The novelty of this work are: (1) the DLCMNPs are invented from low cost and locally available biomass, and (2) it has the capability to reduce IFT which is a vital parameter of EOR process.

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The purpose of this scoping model study of Zarrarah field, with ~14 BSTB, and ~30 TSCF OIIP and GIIP respectively, was to show that natural gas cap could be used in a zero emission power plant to generate electricity, produce NGLs, and capture carbon dioxide gas. Over the lifetime of the project, the injected CO2 gas will displace the oil column in the heterogeneous carbonate rock system in a miscible gravity dominate mode. Petrophysical data needed to construct a simulation model for Zarrarh field was collected from literature review. We used 12 analogous rock types from neighboring fields of Asab and Bu Hasa. The CMG-GEM reservoir model used 18 components to describe the fluid properties and to verify no asphaltene drop out near the producing well bore. The model was calibrated on total field oil production and gas oil ratio and then various CO2 flooding scenarios were tested to optimize recovery and minimize gas coning in the horizontal well flooding patterns. The current production method for Zarrarah field is gas cap expansion with recycling of lean methane gas into the gas cap for pressure maintenance and recovery of NGLs. The averaged over the heterogeneous rock type regions, the miscible CO2 flood recovered at least 20% additional oil for each reservoir sector. The percentage of produced NGLs from the total in place will increase from 23% to 36% over the lifetime of the project with CO2 extraction. This production method will also supply for UAE and KSA at least 20 GW of zero emissions electric power for the next thirty years. CO2 reduces the oil viscosity and reduces gas coning by swelling the oil in the natural fractures system. The optimal CO2 injection technique is flank injection starting at the northern end of Zarrarah field. At the end of project life, the CO2 gas reserves should approach 30 TSCF to flood other reservoirs in the Empty Quarter such as Shah oil field. The novelty of this work is designing the first economic and zero emission power plant for EOR in KSA and UAE. Generating the first economic man-made CO2 storage reservoir for future miscible oil recovery in the Empty Quarter. The increased NGL recovery will help supply the feed stock for the petrochemical industry for the next 30 years. This technique has also the ability of providing a fresh water source for low salinity water flooding or local inhabitants.