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Shirazi M.M.A.,Islamic Azad University at Omidieh | Kargari A.,Amirkabir University of Technology | Shirazi M.J.A.,Islamic Azad University at Tehran
Desalination and Water Treatment | Year: 2012

Membrane distillation (MD) is a non-isothermal membrane separation process. It is based on the phenomenon that pure water in its vapor state can be extracted from aqueous solutions, with vapor passing through a hydrophobic microporous membrane when a temperature difference is established across it. In this work, three commercially available hydrophobic microporous membranes were used for seawater desalination via direct contact MD. The effects of pertinent operating parameters on the permeation flux have been studied. A plate and frame module was used for seawater desalination. Long-term performance evaluation was carried out to evaluate the process as a stand-alone desalination alternative. The results indicated that polytetrafluoroethylene membrane had the best performance when a hot feed temperature of 80 °C with 800 ml/min flow rate was used. At optimum condition a 99.99% salt rejection was achieved. © 2012 Desalination Publications. All rights reserved.


Akhlaghi M.,Islamic Azad University at Omidieh | Emami F.,Shiraz University of Technology
Journal of the Optical Society of Korea | Year: 2013

This paper presents an efficient evolutionary method to optimize the gain ripple of multi-pumps photonic crystal fiber Raman amplifier using the Fuzzy Adaptive Modified PSO (FAMPSO) algorithm. The original PSO has difficulties in premature convergence, performance and the diversity loss in optimization as well as appropriate tuning of its parameters. The feasibility and effectiveness of the proposed hybrid algorithm is demonstrated and results are compared with the PSO algorithm. It is shown that FAMPSO has a high quality solution, superior convergence characteristics and shorter computation time.


Shirazi M.M.A.,Islamic Azad University at Omidieh | Kargari A.,Amirkabir University of Technology | Tabatabaei M.,Agricultural Biotechnology Research Institute of Iran
Chemical Engineering and Processing: Process Intensification | Year: 2014

In this study, nine flat-sheet commercially available hydrophobic PTFE membranes were used in desalination by direct contact membrane distillation and their characteristics were investigated under different operating conditions including feed temperature, feed flow rate, cold stream flow rate, and feed concentration. Membrane properties, i.e. pore size, thickness, support layer, and salt rejection were also studied. Moreover, membrane module designs including flow arrangements (co-current, counter-current and tangential) for process liquid and depth both on hot and cold sides were tested experimentally. Finally, the long-term performance of the selected membranes for direct contact membrane distillation as a stand-alone desalination process was investigated. The results indicated that increasing feed temperature, hot feed flow rate, and module depth on the cold side led to increase permeate flux. On the other hand, increasing membrane thickness and module depth on the hot side (at constant flow rate) had negative effects on the flux. The highest permeation flux and salt rejection was achieved when the membranes with a pore size of 0.22. μm were used in the cross-current follow arrangement of hot and cold streams. In addition, the requirements for support layer for a successful DCMD process has been extensively discussed. © 2013 Elsevier B.V.


Akhlaghi M.,Islamic Azad University at Omidieh
Journal of Modern Optics | Year: 2015

Using particle swarm optimization method, an optimized gain ripple was found for two-sided coupled integrated spaced sequence of Si and Si1-xGex microring resonator Raman amplifier. This amplifier had two sides of ring resonators, each consisting of eight rings. On the one side, the microrings were made of Si, and on the other, they were constructed from microSiGe rings. Resonance frequencies of a ring in Si row were equal to those of a ring in the SiGe row; therefore, for a ring of the first row and a ring of the second row, only one pump was used. © 2014 Taylor & Francis.


Cheraghian G.,Islamic Azad University at Omidieh
Petroleum Science and Technology | Year: 2016

The resources of heavy oil in the world are more than twice those of conventional light crude oil and the technology utilized for the recovery of heavy oil has steadily increased recovery rates. Polymer flooding is the most commonly applied chemical enhanced heavy oil recovery technique. However, still there is a need for a large amount of polymer, leading to high operational costs, presenting a big challenge in technologies. This challenge can be addressed by considering the newly emerging nanomaterials especially those made from silica. In this work, the author focuses on roles of silica nanoparticles on polymer viscosity and improvement of recovery in heavy oil recovery. The author presents the results obtained from a coreflood experiment with polymer injection in heavy oil at 1320 mPa.sec viscosity. The results indicate that polymer flooding with higher viscosity can significantly improve oil recovery. These laboratory results will be helpful for the planning of nano silica polymer flooding for heavy oil reservoirs. Also flooding test showed a 8.3% increase in oil recovery for nanosilica polymer solution in comparison with polymer solution after one pore volume fluid injection. © 2016 Taylor & Francis Group, LLC.


Cheraghian G.,Islamic Azad University at Omidieh
Petroleum Science and Technology | Year: 2016

ABSTRACT: In recent years, polymer flood of heavy oil has been extensively studied in laboratories and successfully applied in several fields. Polymer flooding is the most successful chemical enhanced oil recovery method. However, still, the need for a large amount of polymer, leading to high operational costs, presents a big challenge in technologies. This challenge can be addressed by considering the newly emerging nanomaterials. In this work, the author focuses on roles of TiO2 nanoparticles on polymer viscosity and improve recovery in heavy oil recovery. He present the results obtained from a coreflood experiment with polymer injection in heavy oil at 1320 mPa.sec viscosity. Nanopolymer exhibits an outstanding flow behavior and enhanced oil recovery performance in coreflood displacement tests compared to base polymers. The results indicate that polymer flooding with higher viscosity can significantly improve oil recovery. Flooding test showed about 4% increase in oil recovery for nanopolymer solution in comparison with polymer solution after one pore volume fluid injection. © 2016, © Taylor & Francis Group, LLC.


Cheraghian G.,Islamic Azad University at Omidieh
Petroleum Science and Technology | Year: 2015

High molecular weight and water-soluble synthetic organic polymers are currently being used in the field with the hope of enhancing the recovery of oil by water flooding. Nanotechnology has been used in many applications and new possibilities are discovered constantly. Recently, a renewed interest arises in the application of nanotechnology for the upstream petroleum industry. The author focuses on roles of clay nanoparticles on polymer viscosity. Polymer-flooding schemes for recovering residual oil have been in general less than satisfactory due to loss of chemical components by adsorption on reservoir rocks, precipitation, and resultant changes in rheological properties. Rheological properties changes are mainly determined by the chemical structure and mix of the polymers, surface properties of the rock, composition of the oil and reservoir fluids, nature of the added polymers, and solution conditions such as salinity and temperature. On the other hand, the author's focus is on viscosity, temperature, and salinity of solutions polyacrylamide polymer solutions with different nanoparticles. Results show that ultimate oil recovery by nanoclay polymer flooding enhances by a factor of 5.8% in comparison to polymer flooding high salinity and temperature. Copyright © 2015 Taylor & Francis Group, LLC.


Esmaeili A.,Islamic Azad University at Omidieh
AIP Conference Proceedings | Year: 2011

Nanotechnology could be used to enhance the possibilities of developing conventional and stranded gas resources and to improve the drilling process and oil and gas production by making it easier to separate oil and gas in the reservoir. Nanotechnology can make the oil and gas industry considerably greener. There are numerous areas in which nanotechnology can contribute to more-efficient, less-expensive, and more-environmentally sound technologies than those that are readily available. We identified the following possibilities of nanotechnology in the petroleum industry: 1-Nanotechnology-enhanced materials that provide strength to increase performance in drilling, tubular goods, and rotating parts. 2- Designer properties to enhance hydro-phobic to enhance materials for water flooding applications. 3- Nano-particulate wetting carried out using molecular dynamics 4- Lightweight materials that reduce weight requirements on offshore platforms 5- Nano-sensors for improved temperature and pressure ratings 6- New imaging and computational techniques to allow better discovery, sizing, and characterization of reservoirs. © 2011 American Institute of Physics.


Cheraghian G.,Islamic Azad University at Omidieh
Petroleum Science and Technology | Year: 2016

Nanotechnology has the potential to profoundly change enhanced oil recovery and to improve mechanism of recovery, and it is chosen as an alternative method to unlock the remaining oil resources and applied as a new enhanced oil recovery method in last decade. The objective of this research is identification of potential of nanotitanium dioxide as an appropriate agent for improving the efficiency of surfactant flooding in five-spot glass micromodels. In this work a series of solvent injection experiments was conducted on horizontal glass micromodels at same conditions. Surfactant solutions and newly developed nanosurfactant solutions with 1600-2000 ppm sodium dodecyl sulfate were tested. Observations showed that nanotitanium dioxide has appropriate performance in enhancing the oil recovery at surfactant solution, near critical micelle concentration conditions. Also The results of experiments illustrated improvement of heavy oil recovery in micromodel test with nanotitanium dioxide (51.0%). © 2016 Taylor & Francis Group, LLC.


Ashena R.,Islamic Azad University at Omidieh | Moghadasi J.,Petroleum University of Technology of Iran
Journal of Petroleum Science and Engineering | Year: 2011

Experience has proved that in the right conditions, significant technical and economic benefits like formation damage mitigation, increase in the rate of penetration, higher recovery, etc. can be achieved when the correct design of an Under-Balanced Drilling (UBD) program is considered. It is a fact that UBD precise bottom hole pressure (BHP) maintenance ascertains UBD success. Two phase flow through annulus is an ambiguous area of study to evaluate the flow parameters especially bottom hole pressure. Therefore, the ambiguous challenge of UBD hydraulics design which is greatly dependent on the annular pressure drop or BHP could be dealt with by virtue of intelligent solution.Therefore in this project, bottom hole pressure is estimated through 3 proposed methods. First, ANN with 7 neurons in its hidden layer is utilized to solve the non-straightforward problem of two phase flow in annulus (back propagation neural network, BP-ANN). The next methods correspond to optimized or evolved neural networks. Much more promising results were obtained when the highly efficacious tool of Ant Colony Optimization (ACO) was utilized as the second method to optimize the weights and thresholds of the neural networks. This method is called ACO-BP. In the third method called GA-BP, a trained neural network evolved by highly effective optimizing tool of Genetic Algorithm (GA) is trained. GA-BP shows perform better than BP-ANN. As a result, both GA and ACO are strongly shown to be highly effective to optimize the performance of the neural networks to estimate BHP. © 2011 Elsevier B.V.

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