Mature oil reservoirs surrounded with strong edge and bottom water drive aquifers experience pressure depletion and water coning/cresting. This laboratory research investigated the effects of bottom water drive and gas breakthrough on immiscible CO2-Assisted Gravity Drainage (CO2-AGD), focusing on substantial bottom water drive. The CO2-AGD method vertically separates the injected CO2 to formulate a gas cap and Oil. Visual experimental evaluation of CO2-AGD process performance was performed using a Hele-Shaw model. Water-wet sand was used for the experiments. The gas used for injection was pure CO2, and the “oleic” phase was n-decane with a negative spreading coefficient. The aqueous phase was deionized water. To evaluate the feasibility of the CO2-AGD process without any bottom water drives, it was first used. The experimental results demonstrated that existence of bottom water drive affected oil recoveries due to pressure support. Oil recovery before gas breakthrough increases proportionally with bottom water drive intensity. The gas breakthrough time recoveries for CO2-AGD1, CO2-AGD2, and CO2-AGD3 runs were 38.68%, 50.70%, and 60.85% of OOIP. The pressure gradient along the physical model decreases as bottom water drive intensity increases. The CO2-AGD approach delayed gas breakout by 72 min. As aquifer strength increases, gas breakthrough is delayed. In the three CO2-AGD runs and after breakthrough occurrence, the injector-producer pressure difference decreased due to the residual heads of oil and water columns above the horizontal well. As long as oil and water exist in the model, the pressure differential will not be zero, and the relative permeability and capillary trapping also control this phenomenon. Finally, it was demonstrated that there is a direct correlation between the strength of the aquifer and the oil recovery factor. The strength of the aquifer positively affects the oil recovery at breakthrough and the ultimate oil recovery.
This paper presents a study to investigate the behavior of post-tensioned segmental concrete beams that exposed to high-temperature. The experimental program included fabricating and testing twelve simply supported beams that divided into three groups depending on the number of precasting concrete segments. All specimens were prepared with an identical length of 3150 mm and differed in the number of the incorporated segments of the beam (9, 7, or 5 segments). To simulate the genuine fire disasters, nine out of twelve beams were exposed to a high-temperature flame for one hour. Based on the standard fire curve (ASTM – E119), the temperatures of 300◦C (572◦F), 500◦C (932◦F), and 700◦C (1292◦F) were adopted. Consequently,
... Show MoreSeparation of uricase from Pseudomonas aeruginosa was done using (70%) satu-ration ammonium sulphate, and purification of this enzyme was done by ion ex-change chromatography on DEAE- cellulose column and eluted with linear NaCl (0-1M). Partial purified uricase gave an activity of (4.9 u/ml), protein concentration of (0.56 mg/ml), specific activity of (8.75 unit/mg) with purification folds (8.4) and a yield of (48%). The maximum purified uricase activity was detected at 35ºc and pH 8.5 with (0.12 mM.uric acid). The results shown that red cabbage extract (RCE) contain flavonoides which contain phenolic compounds and anthocyanines which glycoslated with mono or dimolecules of saccharides, while test for alkaloids, ster-oids, saponins and
... Show MoreThis paper presents an improved technique on Ant Colony Optimization (ACO) algorithm. The procedure is applied on Single Machine with Infinite Bus (SMIB) system with power system stabilizer (PSS) at three different loading regimes. The simulations are made by using MATLAB software. The results show that by using Improved Ant Colony Optimization (IACO) the system will give better performance with less number of iterations as it compared with a previous modification on ACO. In addition, the probability of selecting the arc depends on the best ant performance and the evaporation rate.
We investigated at the optical properties, structural makeup, and morphology of thin films of cadmium telluride (CdTe) with a thickness of 150 nm produced by thermal evaporation over glass. The X-ray diffraction study showed that the films had a crystalline composition, a cubic structure, and a preference for grain formation along the (111) crystallographic direction. The outcomes of the inquiry were used to determine these traits. With the use of thin films of CdTe that were doped with Ag at a concentration of 0.5%, the crystallization orientations of pure CdTe (23.58, 39.02, and 46.22) and CdTe:Ag were both determined by X-ray diffraction. orientations (23.72, 39.21, 46.40) For samples that were pure and those that were doped with
... Show MoreThe real and imaginary part of complex dielectric constant for InAs(001) by adsorption of oxsagen atoms has been calculated, using numerical analysis method (non-linear least square fitting). As a result a mathematical model built-up and the final result show a fairly good agreement with other genuine published works.
Low bearing capacity of weak soil under shallow footings represents one of construction problems.
Kaolin with water content converges to liquid limit used to represent the weak soil under shallow
footing prototype. On the other hand, fly ash, which can be defined as undesirable industrial waste
material, was used to improve the bearing capacity of the soft soil considered in this research. The soft
soil was prepared in steel box (36×36×25) cm and shallow square footing prototype (6×6) cm were
used .Group of physical and chemical tests were conducted on kaolin and fly ash. The soft soil was
improved by a bed of compacted fly ash placed under the footing with dimensions equal to that of
footing but with different de
In order to save natural resources, recycling necessarily becomes a top priority for all of us, to save exhaustible resources, produce green energy and preserve the environment.
In this perspective, we are trying to valorize a waste of animal origin, largely neglected by the actors of materials, through an industrial transformation into a biological charge to make new sustainable bio-composite materials.
Using a tensile test bench, we try to mechanically characterize this biomaterial of renewable resources that, unlike eco-composites, has been neglected by the material actors.
Obtained from waste, with a high recycling potential and from renewable resources, the bio-charge to be analyzed will be injected, later in different poly
In this paper, we calculate and measure the SNR theoretically and experimental for digital full duplex optical communication systems for different ranges in free space, the system consists of transmitter and receiver in each side. The semiconductor laser (pointer) was used as a carrier wave in free space with the specification is 5mW power and 650nm wavelength. The type of optical detector was used a PIN with area 1mm2 and responsively 0.4A/W for this wavelength. The results show a high quality optical communication system for different range from (300-1300)m with different bit rat (60-140)kbit/sec is achieved with best values of the signal to noise ratio (SNR).
Euphrates River extends about 125 km within the study area located in Annassiriyah City, Dhi Qar Governorate, Iraq. The impact of the seven hydraulic structures on the discharge capacity of the Euphrates River needs to be considered. The main objectives of this research are to increase the discharge capacity of Euphrates River within Annassiriyah City during flood seasons and study the impact of these hydraulic structures on the river capacity by using HEC-RAS 5.0.3 software. Five scenarios were simulated to study the different current condition of Euphrates River within Annassiriyah City. Other additional four scenarios were implemented through river training to increase the river capacity to 1300 m³/s; it is the flood
... Show MorePlants commonly used in traditional medicine are assumed to be safe. This safety is based on their long usage in the treatment of diseases according to knowledge accumulated over centuries. One such plants is Aloe vera which has been used medicinally for centuries. Recent widespread importance of commercial Aloe vera has encouraged scientists to scientifically assess these products since it contains the anthraquinones which associated with considerable risks. In present study oral administration of 20 μl of Aloe vera extract (experimental group) (G) was given for 21 days to immature male Swiss Webster mice at weaning period. While the control groups (C) were given by the same dose and rout of administration with normal saline only. Afte
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