access deny [1301]
Research field: Coreflood, IFT, Contact Angle, Rehology, Viscometry, Micromodel, Enhanced Oil recovery
Expert: Saeedi Dehaghani Amir Hossein
Phone: 82883979-82883350
Address:
access deny [1026]
In this study, we initially performed interfacial tension (IFT) tests to investigate the potential of using the Persian Gulf seawater (PGSW) as smart water with different concentrations of NaCl, KCl, MgCl2, CaCl2, and Na2SO4. Next, for each salt, at the concentration where IFT was minimum, we conducted contact angle, zeta potential, and micromodel flooding tests. The results showed that IFT is minimized if NaCl or KCl is removed from PGSW; thus, for solutions lacking NaCl and KCl, the IFT values were obtained at 26.29 and 26.56?mN/m, respectively. Conversely, in the case of divalent ions, minimum IFT occurred when the concentration of MgCl2, CaCl2, and Na2SO4 in PGSW increased. Specifically, a threefold rise in the concentratio
This research aims to present asphaltene fraction of oil by FTIR spectrum technique. For this purpose, three different oil samples with various SARA contents and almost identical API degrees were utilized in this research. Two asphaltenic oil samples were referred to as ‘A’ and ‘B’, and the aliphatic oil sample was named as ‘C’. First of all, the asphaltene fraction was extracted through the IP-143 test. The possible chemical bonds and functional groups were identified through NMR tests. Then, the FTIR spectrums of the oil samples and the extracted corresponding asphaltene fractions were taken. The interpretations were used to find the functional groups in the FTIR of the oil samples that belong to the asphaltene fractions. Amon
This research aims to investigate the efficiency of a new hybrid method of smart water imbibition assisted with microwave (MW) radiation. Some experiments including the contact angle measurement, attenuated total reflectance (ATR), zeta potential evaluation, oil viscosity measurement, and smart water imbibition were studied to find the effect of the MW radiation on the performance of the smart water imbibition. To capture the controlling mechanisms, it was essential to sustain the temperature in some of the MW treatments. Hence, the rock sections were treated by two methods of dry (MW treating the sections without immersion in the brine water) and immersed (MW treating the sections when they are immersed in the brine water) treatments. It w
Searching for computational approaches for determination of the minimum miscibility pressure (MMP) is highly requested during the miscible gas injection process. New models, namely, the stochastic gradient boosting (SGB) algorithm and two distinct hybrid artificial neural network (ANN) models were used to predict CO2 MMP as a function of reservoir temperature, mole percent of volatile oil components, mole percent of intermediate oil components, molecular weight of pentane-plus fraction in the oil phase, mole percentage of CO2 in injected gas, volatile components, and intermediate components in the injected gas based on 144 published data points. The SGB model was found to provide the better performance. The reservoir temperature turned out
Being one of the most commonly performed EOR methods, polymer injection is used to increase the mobility ratio and decrease water relative permeability to allow the injected fluid to sweep more oil towards the production well. Before the polymer solution is injected into the reservoir through the injection wells, the process of polymer injection must be simulated using commercial numerical reservoir simulators. In order to be able to simulate the process, the viscosity behavior of the solution must be known. Therefore, a model is required to estimate the viscosity of the injected fluids versus shear rate and polymer concentration. In this study, a new mathematical function based on the power-law fluid equation is presented, which can be app
In recent years, several studies have been carried out on the effect of cationic surfactant and smart water on the oil recovery in carbonate rocks. However, limited studies have been conducted on the combination of these two solutions. In the present study, the effect of combining smart water and cetyltrimethylammonium bromide (CTAB), a cationic surfactant, was analyzed. The synergic effect of the smart water and the CTAB was studied using the results of contact angle, interfacial tension (IFT), zeta potential, and spontaneous imbibition tests. The seawater was modified by increasing the concentration of SO42− and was used as the smart water. The results showed that, in the presence of seawater with 2 or 4 time SO42− concentration, cati
Injection of low-salinity or smart water into the reservoir is one of the most common EOR techniques. This technique leads to more oil recovery in comparison to reservoir water and seawater injection. Several mechanisms explain the reasons for this increased recovery level, the most important of which is the wettability alteration towards water-wet conditions. However, in recent years, further mechanisms have been added to the previous ones as the main or complementary mechanism. One of these newly added mechanisms is the performance of oil as a semi-permeable membrane between connate and low-salinity waters. According to this mechanism, water molecules move from low-salinity water through oil to connate water due to the difference in their
Among all EOR methods, chemical flooding using wettability alteration materials may be a promising choice to enhance oil recovery. The present study involves a combination of smart water and anionic and cationic surfactant injection as a new approach of EOR in an oil wet carbonate reservoir. CTAB as a cationic and SDS as an anionic surfactant were considered. The modified seawater from Persian Gulf was selected as the smart water. The effects of the smart water salt content and the concentration of the surfactants were measured. The optimum salt concentration of smart water was obtained when SW-3KCl, SW-1NaCl, and SW-4Na2So4 were used. Moreover, the optimum smart water combined with the surfactants was estimated to be 0.1CMC of SDS and 0.9
Condensate formation near the wellbore is considered as one of the challenging problems affecting the production from a gas reservoir. Two types of mechanical and electromagnetic (EM) waves were implemented to remove this production barrier. Two core plugs with different mechanical and electrical properties were saturated with condensate fluid belonging to a gas field in the south of Iran and then subjected to the ultrasonic (US) waves with two frequencies of 37 and 80 kHz at different powers and time durations. Besides, the saturated plugs were exposed to the microwaves (MWs) with different powers at an identical wave frequency of 2.45 GHz. The experimental results showed that the ultimate removal factors from the plugs using the US
There are numerous correlations and thermodynamic models for predicting the natural gas hydrate formation condition but still the lack of a simple and unifying general model that addresses a broad ranges of gas mixture is highly felt. This study was aimed to develop a user-friendly universal correlation based on hybrid group method of data handling (GMDH) for prediction of hydrate formation temperature of a wide range of natural gas mixtures including sweet and sour gas. To establish the hybrid GMDH, the total experimental data of 343 were obtained from open articles. The selection of input variables was based on the hydrate structure formed by each gas species. The modeling resulted in a strong algorithm since the squared correlation coeff
This research aims to propose a thermodynamic model for predicting asphaltene precipitation upon diluting a crude oil with a paraffinic solvent. To this end, a thorough mathematical formulation was carried out to derive a novel micellization model based on the associative properties of asphaltenic compounds. It was assumed that asphaltenes exist in the oil both as monomeric molecules and aggregated cores; with stabilization latter by attachment of resin on its periphery. The aggregation equilibrium was established by taking into account asphaltene's lyophobic tendency, heat of resin adsorption, and interfacial tension between micelle and oil media which is the main driving factor contributing to Gibbs free energy of micellization. In this s
Waterflooding in fractured reservoirs is a challenging task due to the presence of high conductive flow pathways such as fractures. Much of the injected water passes through fractures without sweeping the oil in the low permeable area, which results in an early breakthrough. Implementing deep conformance control techniques can be a remedy for this early water breakthrough. pH-sensitive microgel injection is a conformance control method in which the dependency of microgel viscosity to pH guarantees easy injection of these microgels into formations at low pH environments. Because of the geochemical reactions among rock minerals, microgels, and a pre-flushing acid, the microgel pH increases; therefore, these microgels swell and block high cond
More than half of the world's discovered oil is held in carbonate reservoirs, most of which are naturally oil-wet fractured reservoirs. Oil Recovery efficiency can be improved noticeably if the rock wettability is changed from an oil-wet to a water-wet state. However, what factors control the wettability alteration are not clearly specified. In this study, a comprehensive mechanistic study is performed using different experimental tools to investigate the effects of active ions, non-active ions, CTAB, and different combinations of ions and CTAB on the sample rock's wettability. The results indicate that using CTAB and a smart water solution, in which the sodium and chloride ions are eliminated and the concentration of sulfate ions is increa