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Various studies have confirmed that water salinity and its composition significantly affect the efficiency of the waterflooding process. Field-scale operation of low-salinity water injection has been proven to be a cost-effective enhanced oil recovery (EOR) method which is also compatible with the environmental regulations. Although this method has satisfactory results, it faces some challenges, such as in-situ mixing of the injection low-salinity water with the saline water in the host reservoir. The salinity of the injected water increases, as it contacts the high-salinity reservoir brine in the pores. This phenomenon significantly impairs the efficiency of this technique, and increases... 

So far, many studies have been carried out on the core-scale regarding the effects of hysteresis on the macro-scale properties of systems including fluids and porous rock, however, many issues related to the physics of the problem (especially regarding the way fluids are distributed and the trapping of the non-wetting phase) at the pore-scale need further investigation. In the process of multiphase fluid flow in porous media, hysteresis refers to the dependence of the results of the fluids’ displacements on the history of fluid saturation and the direction of saturation changes (increasing or decreasing). The first step to investigate the hysteresis effect is to determine the amount of fluid... 

Water injection is known as one of the most efficient and affordable techniques to displace the oil in the reservoirs. To increase oil recovery efficiency through water injection operation, recently low salinity water injection or water containing a certain amount of effective ions (engineered/low salinity water) is proposed. Besides, improving this technique is also adopted in the oil industry using certain chemicals like surfactants to change the interfacial tension or rock wettability for more oil recovery. In order to study and model the mechanisms involved during surfactant flooding, molecular dynamics simulation is utilized here as a novel technique. The advantage of this method over... 

Oil and gas reservoirs in various parts of the world have declined over time, despite a high percentage of oil. Due to the increasing need for hydrocarbon resources, the need for more cost-efficient harvesting methods and less environmental damage is felt. Injection of saline water is one of the most cost-effective ways of harvesting due to the need for no expensive additives. On the other hand, microscopic glass modeling can be used to better understand and understand the performance of saline water at the microscopic scale. In this study we have been able to visualize the effective factors in infusion of saline water. Improved interfacial tensile and particle migration in kaolin-coated... 

In this study, membrane distillation process was used for treatment of high salinity waters. The focus of this study is to simulate and build a setup of membrane distillation process. Since the membrane distillation process is based on the driving force of the temperature difference, the required temperature is provided by both the use of heaters and the use of solar energy. To increase the feed temperature by solar energy, a black polymer coating on the main membrane is used. The main membrane used in this process is PVDF polymer and the polymer coated on the surface is the PAN polymer. After simulating and constructing the laboratory setup, the influence of a variety of parameters on the... 

From previous years, water injection was considered as one of the most common methods for enhanced oil recovery. But recently much attention has been paid on the use of low salinity water (LSW) as an enhanced oil recovery fluid. The main mechanism that causes improve oil recovery is wettability alteration to a more water wet state. The change observed in recovery factor during LSW flooding induced from changes in relative permeability and capillary pressure when different levels of salinity are used. However, a few researchers tried to evaluate how macroscopic flow functions depend on the salinity of injected water. To this end, a series oil displacements by water performed on sandstone rock... 

Visual investigation of the low salinity water injection into micromodel is the goal of this research. Although many researches have been performed to realize the dominating mechanism behind the increased oil recovery after low salinity water injection, many contradictions exist among the studies. Mechanisms are generally divided into two classes. One class is due to fluid/fluid interactions and the other one is due to fluid/rock interactions. A comprehensive set of experiments are conducted in this study to find out the dominating mechanism behind low salinity water injection under the existing conditions of the experiments. Effect of different wettability condition and presence and absence... 

As the reservoir matures, especially in fractured reservoirs, oil production is usually accompanied by the production of some unwanted water. Water production causes environmental problems and imposes high costs on the production system, including the cost of separating water and oil, corrosion of facility, and sometimes, leading to abandoning well. One way to solve this problem is to use gels as a blocking agent. Today, preformed particle gels are used as an alternative to in situ gels, which can solve some issues of in-situ gels, such as uncertainty in gelling time and penetration depth.This research comprises three main parts. In the first part, four samples of preformed particle gels... 

Removing nitrogen, as one of the most important contaminants of surface and ground water, needs to be considered. Since this material minimizes water quality and makes it useless. On the other hand, many industries as refineries have saline wastewater which their salinity removal is not economical by physical and chemical methods and is often impossible. Although biological treatment of saline wastewater has its problems, biological nitrification and denitrification are efficient and economical methods for nitrogen removal from industries saline wastewater. In this research, moving bed biofilm reactor (MBBR) adopted from Modified LUDZACK – ETTINGER (MLE) method has been used in order to... 

Water injection, as one of the conventional methods to increase the oil recovery factor has always been at the center of research works for Enhanced Oil Recovery (EOR). The conducted studies show that by controlling the amount and type of ions in the injected water, the recovery efficiency can be improved. In the meantime, most of the investigations are focused on the interaction between water/rock/oil to trace the wettability alteration. However, these interactions especially between the injected water and the oil phase, would lead to change of surface charge distribution of the reservoir rock. Besides, this effect can change some of the characteristics of the fluid phases, especially in... 

There are a lot of industry, including refineries with saline wastewater. Biological wastewater treatment saline pose particular problems and leads to plasmolysis microorganisms in the presence of salt. Remove salt from the wastewater before biological treatment by reverse osmosis or ion exchange and other methods are expensive and often impossible. Remove nutrients from wastewater before disposal and give up their saline for nature is essential. Because the these materials, especially nitrogen and phosphorus can degrade water quality and even make it unusable. So that by increasing the concentration of the algae production is also too much and cause eutrophication of water tanks are grown.... 

Enhanced Oil Recovery (EOR) techniques have become of the main priorities of the oil industry during the high oil price era. It is interesting to note that the common method to increase production from reservoirs is the water injection method, which recovers a very low amount of oil from the oil-wet matrices due to the lack of water imbibition. Previous studies have shown that changing the wettability of rock would critically increase the oil recovery efficiency. This could be achieved by the low-salinity water injection method. In recent years, extensive studies have been conducted on this technique to evaluate its effectiveness for various types of oil reservoirs. Simultaneous injection... 

Asphaltenes are a polydisperse mixture of the heaviest and most polarizable fractions of the crude oil. They are defined according to their solubility properties as being soluble in aromatic solvents but insoluble in light paraffin solvents. Asphaltenes are usually responsible for many problems like wettability changes of the reservoir rock, pore clogging in the reservoir porous matrix and fouling in wellbore tubing and production surface facilities. Most of the studies in the literature, addressing the asphaltene precipitation and deposition (APD), are investigating natural depletion or gas injection process such as CO2 flooding. These studies show that asphaltene deposition and... 

Low salinity water flooding (LSWF) is one of the enhanced oil recovery (EOR) methods that can be applied in both secondary and tertiary recovery techniques. Some reports indicate no incremental oil recovery associated with this method, and the reason can be associated with the binary and tertiary interactions between oil-brine-rock (OBR) systems. In some OBRs, the initial conditions are not favourable in terms of initial wettability. One of the key factors is the local rock heterogeneities in permeability and mineralogy which can affect LSWF performance because the microscopic and macroscopic heterogeneities can impact the flow pattern of the injected water, oil displacement efficiency, and... 

The spatiotemporal dynamic of salinity concentration (SC) in saline lakes is strongly dependent on the rate of water flow into the lake, water circulation, wind speed, evaporation rate, and the phenomenon of salt precipitation and dissolution. Although in-situ observations most reliably quantify water quality metrics, the spatiotemporal distribution of such data are typically limited and cannot be readily extrapolated for either long-term projections or extensive area. Alternatively, remotely sensed imagery has facilitated less expensive and a stronger ability to estimate water quality over a wide range of spatiotemporal resolutions. This study introduces an adaptive learning model that... 

Low salinity/smart waterflooding is simple to apply and a promising enhanced oil recovery method in which ion-tuned saltwater is injected into subsurface oil reservoirs. Many aspects of this operation, in particular those pertaining to nano-scale, are not yet fully understood. The present dissertation is an attempt to shed light on the microscopic properties and behavior of rock/brine/oil interfaces throughout low salinity/smart waterflooding. Several simulations were carried out for oil/brine and calcite/brine categories each containing various ions and hydrocarbons compounds. The surface contribution of non-functional oil compounds (aromatics and aliphatics) near brine medium was... 

Considering the world's diminishing oil reserves, as well as the growing demand for oil and energy consumption, Enhanced Oil Recovery (EOR) techniques are becoming increasingly important in the attempt to improve oil production. Engineering salinity waterflooding has gained widespread attention and popularity in the last two decades due to its environmental friendliness, lack of expensive additives, low operating costs, and ease of use as an oil extraction process. The goal of this study is to use an innovative method to develop a mechanistic approach model that simulates and forecasts the mechanism and performance of the engineered water flooding process. Wettability alteration, the most... 

The study of low-salinity water flooding or smart water flooding as secondary or tertiary oil recovery methods started in 1960 and many researchers have studied the effect of ions types on asphaltene precipitation/deposition during the injecting water into the oil reservoirs. To reduce the asphaltene challenges, one needs to properly investigate this phenomenon and better understanding of the cause of precipitation. It is already known that the amount of asphaltene deposition can be reduced by controlling the deposition criteria. For example, water microemulsion in the oil phase would cause the asphaltenes to be adsorbed on the water oil interface by hydrogen bonds due to heteroatom... 

Due to population growth, per capita change and heterogeneous distribution of water resources, forecasts demonstrate that more than 66% of the world's population will experience water scarcity by 2025. The major concern of desalination is their management of brine, with concentrations and their associated components more than twice the input concentration. Also, when extracting oil, per 1 oil barrel, about 7 to 10 barrels of high saline water are produced. One of the most common methods for disposing of brine is direct discharge into the environment, which, due to its destructive effects, creates serious threats to marine ecosystems. Therefore, it is necessary to desalting these high saline... 

Low-salinity waterflooding (LSWF) is a promising EOR approach that decreases the oil-wetness of reservoir rocks, hence increasing the recovery factor. Despite the importance of the pore-geometry on the performance of LSWF, especially in 3D simulations being affected by corner-flow and roughness, it is not yet investigated, thus in this thesis we aim at studying the aforementioned effects on LSWF. According to the preceding studies, during the drainage phase, the brines in the corners of pores cannot be displaced by oil because of requiring very high capillary pressure; thereby rendering a mixed-wet system. Hence considering this type of wettability is necessary for two-phase flow...