نادیا اسفندیاری

Continuous measurement of factory water quality is important. Current methods of measuring water quality are not efficient enough. In this research, a new method using the concepts of artificial intelligence and machine learning has been proposed to solve the mentioned challenges. The proposed research method has been trained and validated using 472 samples of chemical data in MATLAB software. Each data sample has 6 input attributes (pH, conductivity, water hardness, total water-soluble solids, free chlorine, and alkalinity) and one output attribute (target). The parameters of disturbance matrix, precision, accuracy, and readability have been used to evaluate the efficiency of water quality measurement. The highest accuracy is related to the random forest method. The decision tree, simple Bayes, and vector machine methods are the same. The most refreshing rate is related to the decision tree method. The artificial intelligence method of the proposed decision tree with an accuracy equal to 70%, accuracy equal to 98%, and recall equal to 96% compared to logistic regression methods, Naive Bayesian method, support vector machine, and random forest, shows more efficiency and less error.

This research aimed to investigate optimum operating condition for selective extraction of free amino acids by supercritical carbon dioxide (SFE). OVAT experiment design technique is used, setting temperature and pressure as variables and setting time at 60 minute as constant. Results show that SFE has good efficiency in extraction of alanine, glycine, serine, glutamic acid and histidine while showing unsatisfactory results on others under the chosen operating conditions for this study. Experimental extraction results are plots in excel software which shows maximum selectivity and yield for glutamic acids at (P=14 Mpa T=20 °C) and for glycine at (P=16 Mpa T=60 °C) and for alanine, serine and histidine at (P=20 Mpa T=60 °C). The highest extraction yield (3.5%) was achieved at conditions where glutamic acid, the most abundant amino acid in the sample, had the highest exaction yield.

In this study, salt separation from crude oil was investigated using nickel oxide nanoparticle absorber. The effect of parameters such as pH (4, 5, 6, 7. 8, and 9), time (15, 30, 45, and 60 min), amount of adsorbent (0.25, 0.3, 0.5, 0.75, and 1 g), and temperature (40, 50, 60, and 80 ℃) on the degree of salt separation from crude oil was studied. When the pH was decreased, the salt absorption was decreased.  Increasing the temperature increased the desalting percentage. Also in the alkali range due to the presence of OH- ions in the solution, there is a possibility of better complexation between the adsorbent and the cations. Therefore, the best adsorption was observed at near-neutral pH. The best conditions for salt absorption, pH 7, temperature 80 ℃, absorbance 0.75 g, and absorption time 45 min were obtained.

Magnesium hydroxide is a substance with the chemical formula Mg(OH)2 that is found in nature as an inorganic mineral of brucite. This chemical compound can be synthesized in the form of a solid white powder. It has very little solubility in water. Magnesium hydroxide belongs to a group of compounds of a unique nature due to its large number of desirable properties and applications. Magnesium hydroxide is one of the main antacid compounds such as magnesium milk as well as laxatives. Of course, this compound is also used in other fields such as the food industry, water, and wastewater treatment, and the production of fire retardant sprays.In industrial laboratories, this compound is also used to form and synthesize many chemical compounds such as magnesium oxide. This compound is known as a food additive by the U.S. Food and Drug Administration completely wholesome. For this reason, manufacturers of pharmaceutical products and dietary supplements use this compound. There are many factors that cause the acidification of industrial effluents and wastewater. One of the steps that are necessary for the process of water treatment and distance is pH neutralization. Researchers use magnesium hydroxide for this purpose. Considering the importance of this material in this study, applications and methods of preparation of magnesium hydroxide including precipitation, sonochemical, electrochemical, microwave radiation, etc. were investigated and the factors affecting it were investigated. The advantages and disadvantages of each method and the parameters affecting the final product have been investigated in each method.

Desalination process of seawater by reverse osmosis method, has attracted more attention in recent years, due to its high efficiency, and about 62 percent of seawater is treated by this method. In this process energy recovery devices play an important role in reducing energy consumption and process costs, because on the one hand the energy consumption of high pressure pumps for feeding reverse osmosis membrane is high, and on the other hand 40 percent of feed water is treated with membrane and 60 percent is discharged as a high-pressure waste, which releases a lot of energy. The energy recovery device converts this hydraulic energy of the effluent into mechanical energy and transfers it to the feed pump as a shaft aid or uses it independently to transfer a part of the feed. The purpose of this research is to study energy recovery devices and compare them with each other to select a suitable energy recovery system.

Energy and the environment are two important parameters in the development of countries. The flaring system is the main way to waste energy in refineries and operation units, which emits the highest amount of environmental pollutants. Large volumes of associated gases are of high fuel value. Therefore, paying attention to this section's reuse, performance, and modification is of great importance. In this study, Aspen HYSYS software was used. The combination of incoming gas to flare from the Ahvaz refinery was considered. Sweetening was done with methyl diethanolamine and piperazine. Then, the dehydrate was performed with triethylene glycol. Sweetened gas sent to LNG unit. The results of the output of the software show that the separation of carbon dioxide by 99.99% and hydrogen sulfide by 99.94% has been done. When the gas enters from the bottom of the absorption tower, i.e. tray number 20, it has severe temperature changes from 33.6 °C to 54.5 °C, which can be due to the selective absorption of H2S in the presence of CO2 by MDEA and the polarity of H2S. The movement of gas to the top of the tower is accompanied by an increase in temperature up to tray 19, whose temperature has reached 57.7 °C, which is due to the greatest absorption and mass transfer that has occurred in this tray. From tray 19 to tray 13, absorption and temperature decrease until the system reaches equilibrium. As a result, exhaust gas can be considered sweet gas. LNG production capacity in the liquefy unit is 386,700 kg/h, which economically can have a net profit of 32136,000 $ per year.

Recently, supercritical fluids have been introduced as a suitable environment for extraction. Supercritical carbon dioxide is one of the most commonly used supercritical fluids due to its cheapness, toxicity, inseparability, environmental compatibility, and extraction operations at low temperatures. Low critical temperatures of carbon dioxide have led to its widespread use as a suitable solvent for temperature-sensitive substances such as food and pharmaceuticals. In this study, using supercritical carbon dioxide, extraction of active compounds of Eryngium Billardieri was investigated. In this regard, experiments were conducted on operating the pressure (110, 130 and 150 times), temperature (35, 40 and 45 °C), time (30, 50 and 70 minutes), and the particle size (0.075, 0.1, and 0.2 mm) using Taguchi design in Minitab software. The highest efficiency was obtained under operating conditions of 40 °C, the pressure of 150 bar, the particle size of 0.075 mm, and the time of 50 minutes. Also, using GC-MS test data, the most synthesized material is Di Iso Octyl Ester.

The purpose of this study was to investigate the effect of the addition of nanofluids consisting of nanoparticles of magnesium oxide and polyacrylamide polymer on the drag reduction in the turbulent flow of water in a rough horizontal pipeline. For this purpose, three effective parameters of the process (nanoparticle concentration, surfactant concentration, and Reynolds number) in each pipeline were investigated and optimized by the surface response method. The highest rate of drag reduction was calculated by a numerical optimization method of 82%. The model adequacy was investigated using ANOVA analysis. Given the high values of the coefficient of determination and the adjusted coefficient of determination, it was determined that the data are well described by the second-order empirical model.

Natural gas produced from oil and gas wells often contains hydrogen sulfide and carbon dioxide, which are so-called “sour gasses”. Carbon dioxide (in large quantities) and hydrogen sulfide (even in small quantities) cause many problems during the transmission and consumption of natural gas. In this study, mathematical model for the separation of carbon dioxide and hydrogen sulfide from helium has been investigated with two different membrane species including a ceramic modulus and PEEK-L II and ionic liquids.

The effect of material, diameter, pressure and temperature on separation efficiency has been investigated. The ionic liquid used in this study is [hemim] [BF4]. The ceramic and PEEK-L II was studied. The pressure and concentration during absorption is investigated. The concentration variations of carbon dioxide and hydrogen sulfide in ionic fluid were investigated in time.

For a ceramic modulus, about 50 to 60% of the pressure drop occurs in the first 100 to 120 seconds. For the PEEK-L II modulus, in the first 30 seconds, about 50 to 60% of the pressure drop occurs due to gas absorption. The effect of temperature on the concentration of carbon dioxide and hydrogen sulfide at three temperatures of 25, 50 and 100 °C was investigated. As the temperature rises in the ceramic modulus, the amounts of carbon dioxide and hydrogen sulfide, passing through the membrane, increase.

As the time increases, the concentrations of carbon dioxide and hydrogen sulfide in the ionic fluid are increasing. With increasing temperature from 25 to 100 ° C, the amount of absorbed acidic gases into ionic liquid was increased. The PEEK-L II modules removed more acidic gases than the ceramic modules.

Asphaltene precipitation, as stated in previous studies, plugs the pores in the porous media and causes various problems, including permeability reduction, wettability alteration, and ultimately reduces production. The results of this study showed that this surfactant is able to prevent asphaltene precipitation and is effective in different aqueous phases (DW, SW and CW). In addition to increasing recovery factor in the core flooding test, it was able to alter the wettability of the pores surface from oil-wet to intermediate.

The use of pipelines is one of the most important methods of gas transmission. Leakage in gas transmission lines causes financial and life-threatening damages. For this reason, it is very valuable to obtain information such as maximum safe radius of fire, explosion and leakage of materials. This information can play an important role in dealing with accidents in emergencies. In this study, safe privacy for 42-inch gas pipeline was studied using PHAST software version 7.11. The highest amount of radiation is related to the horizontal state and the lowest amount of radiation is related to the vertical state. The vertical direction has the lowest radiation distance from the propagation source, while the horizontal direction at an angle of 45 degrees shows the highest radiation distance from the propagation source. Simulation results showed the lowest radiation outcome for pressurized environments and the most dangerous radiation for hazardous areas. For example, if the ratio of leakage diameter to hole diameter is 0.25 and leakage mode is horizontal. The safety privacy caused by fire for hazardous areas, enclosed environments and pressure environments is 850, 1070 and 1360 meters, respectively.

In this study, two methods of soxhlet extraction and supercritical carbon dioxide extraction were used to extract the effective substances in bitter orange peel. In supercritical fluid extraction, the effect of operational parameters such as temperature, pressure, dynamic time and particle size at different levels on extraction efficiency was investigated. To investigate the more accurate effect of the parameters, the design of the experiment was carried out and the response method was used and a model was obtained for the percentage of extraction efficiency by changing the parameters. The extracted materials were compared with two methods. One of the most important extracted materials is ostol and limonene. The amount of ostol in oil extracted by supercritical carbon dioxide is significantly higher than soxhlet method. The best extraction conditions with supercritical carbon dioxide, dynamic time of 80 minutes, temperature of 35 °C, pressure of 157.26 bar and particle size of 0.4099 mm were obtained.

Supercritical fluid extraction method is a replacement of conventional methods such as organic solvent
extraction with hex
temperature (35, 45, 55 °C), pressure (150, 175, 200 bar) a
extraction yield in conditions of pressu
ane and mechanical pressing. Because in this method the operation temperature is low and
the solvent does not remain in the final product. In this study, the effect of changing three parameters of
nd particle size (0.074, 0.149, 0.210 mm) on the
extracted oil yield of the medicinal plant of Francoeuria undula using supercritical carbon dioxide was
investigated. The results of the experiments showed that the extraction yield was increased by particle size
reduction and increased pressure. Temperature up to 45 ºC has a positive impact on the extraction efficiency.
However, increased efficiency was observed with increasing temperature more than of 45 °C. The best
re was 200 bar, temperature 45 °C and particle size of 0.074 mm.

In recent years, due to the importance of fluid transfer, much attention has been paid to the amount of energy consumption in this field. Much research has been done over the years on controlling energy consumption and optimizing transmission pipelines. By controlling the pressure drop, which is mainly due to increase friction and drag coefficient, the energy consumption of the fluid transfer pumps can be reduced and the capacity of the transmission pipelines can be increased. Using drag-reduction agents is one of the most important and simplest ways to overcome some of the energy losses during fluid transfer. Drag-reducing agents include surfactants, polymers, microbubbles, and so on. Polymers are widely used as drag-reducing material, and their usage is a fast and cost-effective solution for making changes in transmission pipelines. At very low concentrations, these materials can significantly reduce the frictional forces in pipelines. The use of drag-reducing polymers is a good alternative to increase the capacity of pipelines. Injection of drag-reducing polymers into the lines, in addition to reduce frictional pressure, increases the operational safety of pipelines, especially in worn-out pipes, and reduces energy consumption in pumps. Due to the remarkable properties of drag-reducing polymers in horizontal pipelines, their application in pipelines has been investigated in this study. Also, the parameters affecting the reduction of friction forces using drag-reducing polymers have been reviewed.

In any plant, there are hundreds chemical compositions with composition of percent and different properties. Correct separation of chemical compositions in plant and making relationship between medicinal properties of plant with effective composition can make mass production of useful drugs and likewise can prevent effects of compositions directly medicinal plant that due from other harmful compositions in plant, sometimes it can prevent. In this research, extraction of effective substance from carob plant using supercritical carbon dioxide combined with ultrasonic waves, was investigated. The supercritical fluid extraction yield was increased with increasing of pressure and particle size reduction. The use of ultrasonic wave increased the efficiency of the extraction. The best experimental conditions were obtained at pressure 210 bar, temperature 35C, particle size 0.4 mm and frequency 37 kHz. In this condition, the amount of extraction efficiency is 3.7825. The gained essential oil by Clevenger and by extraction with supercritical fluid analyzed by GC and GC-Mass. After the analysis of the extracted essential oil, Acetamide, Nerolidol, Pyrrolidine, and Stigmast was selected as effective materials. Also, extraction yield (3.7825) by supercritical fluid was better than Clevenger method (1.02).

Nanocomposites are a new class of materials that have at least one of their major constituents, at least in one dimension, in the range of one to one hundred nanometers. Typically, nanocomposites have different and superior properties in terms of mechanical and physical properties than conventional composites.

In this study, polyvinyl acetate was prepared by emulsion polymerization for polymer matrix. Then the diamond nanoparticles were modified with silane agent. Finally, polyvinyl acetate / diamond nanocomposite was prepared and analyzed with 0.5, 1, 1.5 and 2 wt% of modified diamond nanoparticles. To determine the properties and structure of the nanocomposite, FTIR, TGA, RMS, FESEM, oxygen permeation analysis was used in the films produced and contact angle measurements.

FTIR Analysis revealed that the modification of the diamond nanoparticles with the silane agent was well performed. FESEM images show that homogeneous nanocomposites were created. Oxygen permeability in polyvinyl acetate / diamond nanocomposite film decreases with increasing percentage of modified nanoparticles in nanocomposite. This is a valuable property if this nanocomposite is used as a fruit preservative coating. Contact angle measurement of polyvinyl acetate / diamond nanocomposite showed that by increasing the amount of modified diamond nanoparticles from 0.5 to 2 wt %, the hydrophobicity of nanocomposite film increased. Therefore, by increasing the specific amount of nanoparticles to the polymer matrix, the polymer properties such as heat resistance and tensile strength are increased which increases the efficiency of the polymer.

Many parameters affect the efficiency of enhanced recovery operations in methane-containing coal beds. Some of the most important parameters in this research were studied. The best output for performing enhanced recovery of these parameters was obtained in ECLIPSE reservoir simulation software. After selecting the data for sensitivity analysis, the corresponding models were defined with different conditions. Then the results of this simulation were analyzed. Sensitivity analysis indicators include the amount of produced carbon dioxide, as well as the rate of this product plus the amount of carbon dioxide stored in the reservoir which is important for the oil and gas industry from the environmental point of view. According to the results of the sensitivity analysis in line with the studied parameters, it can be stated that if the permeation parameters and the porosity of the slit system be lower than a certain extent, they will lead to failure in the process of enhanced recovery. Meanwhile, the other three parameters, reservoir pressure, Langmuir pressure, and Yang coefficient, only affect the efficiency of the enhanced recovery operation.

The fossil fuel sources are decreasing, and the use of biofuels has been recently considered. Among biofuels, biodiesel is considered more because of the environmental benefits. In this study, CaO/CuFe2O4/C nanocatalyst was used to produce biodiesel from Moringa oleifera oil. Different analyses such as TGA, EDX, XRD, FTIR, SEM, and TEM were applied to characterize physical and chemical properties of the CaO/CuFe2O4/C nanocatalyst. Also, Taguchi method was used to determine the biodiesel yield. Moreover, the effective parameters such as methanol/oil ratio (1:12 mol/mol), reaction time (4 h), reaction temperature (60 oC), and catalyst content (3%) were determined as optimal conditions on biodiesel production yield. Additionally, the maximum biodiesel yield was determined 98.69% in these conditions. Moreover, the physical properties of biodiesel/diesel mixtures like density, flash point, kinematic viscosity, pour point, and cloud point were studied, and the results were compared with ASTM D14214 and ASTM D 6751 standards. Finally, the results showed that these properties were in the standard range; in addition, pour point and cloud point are not proper for cold weather.

Today, one of the problems in gas transmission lines is the phenomenon of gas hydrate, which, by combining light gases with water molecules under special conditions of temperature and pressure, forms a substance similar to ice that contains a large amount of gas. Therefore, it is very important to study the variables and factors affecting the formation and removal of hydrates. In this research, Soroush-Abuzar gas pipeline was simulated with Hysys software and the hydrate formation conditions in 30 kilometers of gas transmission were investigated. The results of this study reveals that in the studied pipelines, the temperature is 50 C and the pressure is 25 bar, the best process condition in which there is no possibility of hydrate formation. Also, the analysis of pressure and temperature profiles shows that as the pipe length increases, both parameters tend to descend.

One of the efficient methods for enhanced oil recovery from a petroleum reservoir is the surfactant injection in the presence of alkaline material. Moreover, the contact angle of water and reservoir rock is reduced in the presence of surfactants. On the other hand, this material changes the interfacial tension. The alkaline materials in the present of surfactants also help the reduction of interfacial tension and the wettability alteration of reservoir rock. In this research, the effect of concentration (0.05, 0.1, 0.3, 0.5 wt %) and shelf-life of surfactant dodecyltrimethylammonium bromide in the presence of different concentrations of sodium carbonate (0.5, 1, 1.5, 2, 2.5 wt %) on the interfacial tension and wettability alteration of carbonated rocks of the Asmari petroleum reservoir were analyzed. The results of these experiments showed that surfactant dodecyltrimethylammonium bromide reduces the interfacial tension and alters the wettability of reservoir rock to the water-wet state. Furthermore, the interfacial tension and contact angle is reduced in the presence of sodium carbonate to a great extent which is one of the effective factors in the amount of oil recovery. By increasing the shelf life of the reservoir rock in contact with the solution containing surfactant and sodium carbonate for 7 days, the minimum contact angle was reduced from 59 to 46 degrees. At 0.3 wt.% micelle concentration of dodecyltrimethylammonium bromide and sodium carbonate with an optimum concentration of 0.5 wt.%, the most reduction in interfacial tension was obtained.

Membrane systems are widely used due to their many advantages. The membrane is used for gas separation. In this study, improvement of gas separation properties in the alloy membrane of polyacrylonitrile (PAN) and polysulfone (PSF) was studied by adding aluminum oxide nanoparticles. By addition polysulfone to polyacrylonitrile membrane, the best combination of alloy membranes percentage was obtained. Then, a sol-gel method for making Nano-composite membranes was studied. All membranes were prepared using the solvent evaporation method. The ratio of polymers in the mixed matrix was considered at the rate of PAN 100%, PSF 100 %, (PSF 5%- PAN 95%), (PSF 10% -PAN 90%), (PSF 15% -PAN 85%). Aluminum oxide nanoparticles were placed on the membrane with weight percentages of 2.5, 5, 10, 15, and 20. To study the membrane, SEM and FT-IR analyses were used.  By adding aluminum oxide nanoparticles to the membrane at the weight percentage of 10% and measuring the rate of leakage, it was observed that the leakage rate of carbon dioxide, oxygen, nitrogen, and methane gases increased by 146%, 159%,166%%, and 54%, respectively, compared to the membranes without aluminum oxide nanoparticles. Tests showed that the optimal amount of adding aluminum oxide to improve the properties of the membrane is 10% of the weight percentage.

The bioavailability and solubility of pharmaceutical compounds are increased via size reduction. One of the new method of size reduction is using of supercritical carbon dioxide. This method has some advantage. The process temperature is not high. Therefore, the nature of pharmaceutical compounds is not damage. The supercritical gas antisolvent (GAS) process not occur at arbitrary operating conditions. Thus, the thermodynamic models are necessary to evaluate the suitable operating condition. In the GAS process, the miscibility of antisolvent and solvent is important factor. In this study, the thermodynamic modeling of binary system carbon dioxide-dimethyl sulfoxide and ternary system carbon dioxide- dimethyl sulfoxide- ampicillin was investigated. The Redlich-Kwong equation of state, the Soave equation of state and the Soave-Redlich-Kwong equation of state was used to model.