Enhanced Oil Recovery

The stability of nanoparticles at reservoir conditions is a key for a successful application of nanofluids for any oilfield operations, e.g., enhanced oil recovery (EOR). It has, however, remained a challenge to stabilize nanoparticles under high salinity and high temperature conditions for longer duration (at least months). In this work, we report surface modification of commercial silica nanoparticles by combination of zwitterionic and hydrophilic silanes to improve its stability under high salinity and high temperature conditions. To evaluate thermal stability, static and accelerated stability analyses methods were employed to predict the long-term thermal stability of the nanoparticles in pH range of 4–7. The contact angle measurements were performed on aged sandstone and carbonate rock surfaces to evaluate the ability of the nanoparticles to alter the wettability of the rock surfaces. The results of static stability analysis showed excellent thermal stability in 3.5% NaCl brine...

Deep placement of gel in waterflooded hydrocarbon reservoirs may block channels with high water flow and may divert the water into other parts of the reservoir, resulting in higher oil production. In order to get the gel constituents to the right reservoir depths, a delay in the gelling time in the order of weeks at elevated temperatures will be necessary. In this work, a methodology for controlled gelation of partially hydrolyzed polyacrylamide using hybrid nanomaterials with functional groups as cross-linkers was developed. Two delay mechanisms with hybrid materials and polyelectrolyte complexes were designed and tested. Both mechanisms could significantly delay the gelation rate, giving gelling times ranging from several days to several weeks in synthetic sea water at 80 . Gelling experiments in sandstone cores showed that gel strength increased with aging time. For long aging times, strong gels were formed which resulted in almost no water permeability. A series of coreflooding ...

Lack of relevant screening methods of oil recovery techniques for water flood with added nanoparticles in a given reservoir are hindering its implementation for enhanced oil recovery (EOR) purposes. Moreover, the understanding of the underlying mechanisms of oil increased by nanoparticles must be improved. In this work, we screened twenty-three different types of silica nanoparticles as additives to injection water for oil recovery applications. The nanoparticles were surface functionalised to remain stable in the injection water and be active at the surface. The hypothesis is that the particles will improve the microscopic oil recovery efficiency of water flood in an oil reservoir. The concentrated solution of nanoparticles were prepared to 0.1 wt % concentration in synthetic North Sea water. Crude oil was obtained from a field in the North Sea. The following investigations were carried out to quickly verify the performance of nanoparticle oil recovery: 1) secondary injection throu...

A novel sulfonated alkyl ester (SAE) was developed. The sulfonated alkyl ester has unique chemical structures that aimed to combine the advantages of ester-based and sulfonate-based surfactant in one compound. This surfactant was studied for its performance to reduce interfacial tensions in a wide range of salinity with monovalent and divalent ions and in a light and heavy oil samples. The study showed that the sulfonated alkyl ester surfactant gives a good performance in a light oil sample in a high monovalent ion concentration and also give a good performance in a heavy oil sample in both low and high concentration of monovalent and divalent ions solution.

This paper presents the results of a techno-economics analysis to quantify the potential for storing CO2 and producing lower carbon intensity oil from mature, onshore Australian oil fields located in the Cooper/Eromanga and Surat/Bowen Basins. The work explores the impact of incentivisation, identifies possible sources of CO2 to support CO2-EOR (enhanced oil recovery) deployment, and discusses global CO2-EOR policy. The hypothetical ‘carbon incentive’ assessed in this study resulted in unlocking an additional 40 million metric tons (Mt) of CO2 storage and 73 million barrels (MMBO) of domestic oil production compared to the base case scenario that most closely represent Australia’s current policy and economic settings. Further, the results of this study indicated that, with incentivisation, net-negative carbon dioxide emissions could be achieved by deploying CO2-EOR practices in certain mature oil fields. The study found that there are currently sufficient industrial sources of CO2, ...

Tight fractured sandstones of the Devonian Huamampampa Formation are associated with large gas discoveries in the sub-Andean fold-and-thrust belt of southern Bolivia. A LIDAR-based fracture characterization of the Abra del Condor backlimb anticline, a structural-stratigraphic analog, is used as the basis for a fracture stratigraphy determination. Fracture characterization using LIDAR is integrated with outcrop scanlines and is framed by stratigraphy and structural positions within this thrust-related anticline. SEFL software was used to process LIDAR data, dividing the outcrop by orientations. A workflow to extract modeled fracture planes and their associated orientations, lengths, and heights results in five fracture sets, partially validated by fracture outcrop scanlines. Multiple virtual scanlines are used to measure fracture intensity, identify fracture stratigraphic units, and define fracture-associated parameters of abundance and size distribution. Our LIDAR-based fracture cha...

Two-phase Darcy’s law is a well-known mathematical model used in the petrochemical industry. It predicts the fluid flow in reservoirs and can be used to optimize oil production using recent technology. Indeed, various models have been proposed for predicting oil recovery using injected nanofluids (NFs). Among them, numerical modeling is attracting the attention of scientists and engineers owing to its ability to modify the thermophysical properties of NFs such as density, viscosity, and thermal conductivity. Herein, a new model for simulating NF injection into a 3D porous media for enhanced oil recovery (EOR) is investigated. This model has been developed for its ability to predict oil recovery across a wide range of temperatures and volume fractions (VFs). For the first time, the model can examine the changes and effects of thermophysical properties on the EOR process based on empirical correlations depending on two variables, VF and inlet temperature. The governing equations obtai...

Computational approach to scientific research such as molecular simulation has gained much attention in recent years as research is gradually becoming dominant in arrears difficult to probe experimentally. In molecular dynamics, the thermodynamic properties of a system of known composition can be obtained at specified temperatures and pressures. In this work, molecular dynamics (MD) simulation was applied to a system of oil and CO2. The temperature and pressure of the system was set at Niger-Delta reservoir condition. Parameters such as CO2 solubility, oil swelling, interfacial tension (IFT), minimum miscibility pressure (MMP) were studied. The simulation model is a mixture of CO2 and oil. Octane molecules were used to represent the crude oil and the TraPPE-UA force field was applied on the octane molecules and set as United-atom style (UA Style). The TraPPE-AA force field was applied on CO2 molecules and set as All-atom style (AA Style). The temperature of the system was set at 344K, which is the temperature condition of the reservoir considered. Simulation result confirms that oil swelling occurs when the injected gas comes in contact with the crude oil. This is because there is a dissolution of the CO2 as it contacts the oil. Both the swelling factor and the gas solubility were confirmed to increase with increase in pressure. Oil swelling will result to an increase in reservoir pressure thereby forcing trapped oil out of pore spaces. Also, as pressure is increased, the IFT decreases in a linear manner. A MMP of 18.15 MPa was obtained from the system, indicating that the two phases will not attend total mixing when the operating pressure is lower than this value. These results will guide CO2 injection projects in the region and aid in the prediction of experimental findings.

Enhanced oil recovery (eor) has been applied in oil field in Indonesiasince 1985. The steamflooding methodhas successfullyprolong an oil field life up to now. Steamflooding is the establish method to improve recovery of heavy oil in Duri Field. However, other method still under several stage such as field trials, pilot project, and works laboratory. This research present the method to improve oil recovery from mature fields. The method known as enhanced oil recovery. There are three stage to produce oil involving primary recovery, secondary recovery, and tertiary recovery or eor. Currently, majority an oil production under primary recovery (25.34 %) and secondary recovery (19.19 %) stage. Due to the low oil recovery from these methods, remaining oil in place in the reservoirs are huge (more than 50 billion barrel). Enhanced oil recovery is the best way to produce more oil from the mature fields. However, eor method consumesmuchtime and needsbig effort from initiation to implementati...