جستجوی مقالات مرتبط با کلیدواژه "enhanced oil recovery" در نشریات گروه "مهندسی شیمی، نفت و پلیمر"

The water injection process is a common method for enhancing oil recovery from reservoirs. However, challenges arise, primarily due to the incompatibility of injected water with both oil and reservoir water. On the other hand, due to the limited availability of fresh water resources worldwide, the use of unconventional water sources is being considered. Among these sources, agricultural drainage water, particularly sugarcane irrigation water, is a significant source. In this study, the compatibility of two samples of sugarcane irrigation water with three samples of oil from southwest Iranian fields was investigated in terms of emulsion formation and organic matter deposition. Additionally, the compatibility of sugarcane irrigation water and a produced water sample was monitored in terms of mineral deposition through laboratory experiments. Furthermore, the results indicate that emulsion formation and phase separation occurred in the emulsion of sugarcane water sample 1 and oil A during the three-hour test period, with a 63% phase separation. However, a stable emulsion without phase separation was observed in the emulsion of sugarcane water sample 2. Similar experiments were conducted with oils B and C, and for both sugarcane irrigation water samples, the phase separation increased from 37% in the initial hours to 82% after three hours. Furthermore, the tendency for emulsion formation changes significantly with variations in the water-oil mixing ratio. On the other hand, no organic deposition resulting from the incompatibility of water and crude oil samples was observed. Overall, sugarcane irrigation water can be a suitable option for injection in some oil fields, but it is important to assess compatibility prior to field implementation. Moreover, no significant deposition was observed when both sugarcane water samples were mixed with the produced water, indicating the possibility of mixing water from different sources for injection. Furthermore, to evaluate the possibility of various depositions due to the injection of sugarcane water into the reservoir, simulation was performed using OLI scale chem software, and the probability of CaCO3, CaSO4, and Fe2CO3 deposition was determined.

Low-salinity or engineered salinity waterflooding is one of the enhanced oil recovery methods, particularly for the carbonate fields in Iran and around the world. Alongside its numerous benefits, evaluating the side effects such as formation damage due to asphaltene instability and deposition is of paramount importance. Until now, research in this area has primarily focused on the investigation of oil-brine interactions, neglecting the influence of the presence of rock as an essential parameter. Therefore, in this paper, to bring the laboratory tests closer to reservoir conditions, the effect of rock presence was examined by creating contact between brine/fluid/sandstone grains and measuring the UV absorption of bulk oil before and after contact with rock and brine. In this regard, a new “indirect” procedure was developed through which the amount of asphaltene deposition in the presence of various brines was determined. Our results indicate that asphaltene deposition follows a non-monotonic trend with salinity, such that it increases at low salinities and decreases at high salinities, and reaches a minimum value at a middle salinity. The results also show that in the presence of two times diluted seawater, more asphaltene deposition occurs compared to other brines. Adding sandstone particles to the oil-brine system increases the amount of asphaltene deposition due to the creation of a new physical surface for asphaltene adsorption due to the influence of electrostatic forces. Detailed examination of the sand particles reveals that the higher the brine salinity, the higher the asphaltene deposition occurs on the particles; with formation brine leading to the highest asphaltene deposition on the particles (over 1.4 micrograms per gram sand). Ultimately, these experimental results contribute to the understanding of the role of sandstone particles on asphaltene instability during low-salinity waterflooding and provide a more accurate way of evaluating asphaltene deposition at more realistic conditions.

As oil production begins in a reservoir, extraction becomes increasingly challenging over time; this is due to pressure depletion and, in most cases, relatively weak natural driving mechanisms, resulting in ultimately producing less than the recoverable volume of oil. Moreover, extending the production life of reservoirs is always a primary concern in the global oil industry, and reservoir owners strive to maximize their resources by employing various cost-effective and efficient methods to produce more oil from their reserves, thereby increasing their income and profits. Most of Iran's reservoirs are also in the latter half of their lifespan and face such challenges. Therefore, it seems that, considering the urgency of the matter, relying solely on conventional (primary and secondary) recovery methods should be avoided to prevent resource wastage and maximize reservoir recovery. Because a significant portion of reservoir hydrocarbons are considered unrecoverable under conventional extraction. To address this issue, effective solutions known as Enhanced Oil Recovery (EOR) methods can be employed. These methods can increase the ultimate recovery factor and reservoir production life by altering the properties of the reservoir rock and fluid. For this purpose, in present research, the effect of different methods of EOR was investigated in one of the wells in one of the country's fields called " Kooh- Rig ". The results showed that the steam injection scenario can be the most suitable method for implementation in the studied field. Of course, more parameters need to be examined for the operational phase. This research has only compared the methods of EOR to show that in the first step, determining the appropriate method of EOR is of particular importance.

The petroleum industry has been focusing on optimizing enhanced oil recovery (EOR) techniques in recent years. Hydrogels have the potential to be used in various sectors of the oil industry due to their unique three-dimensional network structure and environmentally friendly characteristics. However, the application of hydrogels in EOR processes is still limited. This paper introduces a new method of utilizing stable and cost-effective preformed particle hydrogels (PPGs) based on carboxymethyl cellulose for enhanced oil recovery while keeping environmental considerations in mind. The research team conducted various tests such as FTIR analysis, thermal gravimetric analysis (TGA), swelling tests, rheological analysis, contact angle measurement, and micromodel flooding experiments to identify the structural characteristics and performance evaluation of carboxymethyl cellulose-based PPGs. The results of the FTIR analysis confirmed that the chemical structure and polymerization of PPGs were successful. Furthermore, the synthesized samples showed acceptable thermal stability up to 120°C, as indicated by the TGA analysis. The hydrogels demonstrated remarkable swelling and water absorption capacity while retaining their structural integrity. They significantly reduced the mobility ratio, increasing in weight by over 15 times in brine environments at 90°C. The carboxymethyl cellulose-based PPGs also changed the wettability of reservoir rocks from oil-wet to water-wet by reducing the contact angle by 47.88 degrees. Micromodel flooding experiments showed that these hydrogels resulted in a 24% increase in oil production compared to secondary injection, attributed to improved displacement efficiency, reduced mobility ratio, and enhanced surface wettability. On the other hand, polymer injection only resulted in a 15% increase in oil production under similar conditions. The research indicates that these materials have significant potential for enhancing oil recovery under challenging reservoir conditions with high temperature and salinity. Further extensive research on sustainable hydrogels and optimization of their compositions is necessary.

Research topic: One of the new methods in the processes of increasing oil recovery from hydrocarbon reservoirs is the method of using ultrasonic waves. In this research, using ultrasonic waves and their application in a large-scale sample tank, its effect on increasing oil extraction by the numerical method is investigated.

In this research, the modeling process has been performed using MATLAB software. First, by determining the porous environment, the amount of pressure increases due to ultrasonic waves due to solving the sound equations (Helmholtz) by MATLAB k-waves toolbox is investigated. Finally, considering the cumulative production at a specific time from the production well and determining the oil recovery from the reservoir in the presence of a wave, to examine the effect of well location parameters and its distance from the wave generation source, wave production starts time, wave application methods (Pulsed and continuous), is performed at an optimal frequency and power.

According to the modeling results, the closer the wave start time is to the first days of production, the higher the oil recovery rate; So that by starting the application of ultrasonic wave under the power of 5 kW and frequency 20 kHz simultaneously with the production of well oil from the first day, oil recovery compared to oil recovery in the case of starting the wave from the fifty and ninety days, respectively 4/5% and 8% more. Oil recovery is 1.8% higher if the wave is applied continuously to the reservoir at a given time than when pulsed at the same time. The modeling results show that the shorter the distance between the wave source and the production well, the lower the pressure drop in the reservoir area and the higher the oil recovery. According to the results, if the source of wave production is located at a distance of 200 feet from the production well, it will increase by 7.1% compared to the distance of 1800 feet from the oil recovery well.

In recent years, research activities on smart water flooding in oil industry have been increased significantly. Smart water injection, by optimizing the ionic composition and salinity of the injected water, is a promising technique to increase oil recovery. Studies over the past two decades have shown the benefits of smart water flooding over other oil recovery methods. So far, several mechanisms have been proposed to describe the performance of smart water process in literature. However, due to the complex chemical and physical reactions, the contribution of each mechanism in increasing oil recovery factor has not been determined; therefore, it is difficult to predict the performance of reservoirs behavior under smart water flooding. In this paper, smart water injection in carbonate and sandstone reservoirs has been comprehensively investigated. This study includes a review of effective mechanisms, laboratory and field observation and the challenge of smart water flooding in both carbonate and sandstone reservoirs. Finally, the screening criteria of candidate reservoirs for smart water injection are presented and based on that, smart water injection in carbonate reservoirs in southwestern Iran has been assessed.