Amir H Mohammadi - Academia.edu (original) (raw)

Papers by Amir H Mohammadi

Résumé — Utilisation de l’équation de Patel-Teja associée au modèle de van der Waals-Platteeuw po... more Résumé — Utilisation de l’équation de Patel-Teja associée au modèle de van der Waals-Platteeuw pour estimer les équilibres de phase d'hydrates de méthane dans des systèmes eau-éthylène glycol à partir de points de congélation de solutions aqueuses — Un souci important avec les canalisations de pétrole/gaz et la production/les unités de traitement est la possibilité de restriction et de colmatage des écoulement dus à la formation d’hydrate de gaz. En effet le résultat étant de sérieux problèmes opération-nels, économiques et de sécurité. Des inhibiteurs organiques tels que le méthanol et l’éthylène-glycol sont couramment employés pour prévenir la formation d’hydrates de gaz. La connaissance précise des équi-libres de phases de solutions comprenant des hydrates en présence d’inhibiteurs est donc cruciale afin d’être en mesure d’éviter tout problème de formation d’hydrate de gaz et pour concevoir et optimiser la production, le transport et les équipements de traitement. Des donnée...

Reservoir fluid properties, such as oil formation volume factor and bubble point pressure, are vi... more Reservoir fluid properties, such as oil formation volume factor and bubble point pressure, are vital parameters in many computations associated with petroleum engineering. These computations include hydrocarbon reserve estimation, and consequently, economic efficiency evaluation, flu id flow in porous media, and improved and enhanced oil recovery. Prior to the computations, the pressure -volume-temperature (PVT) properties of reservoir oil must be determined. PVT properties, in turn, are ascertained either by empirical methods, laboratory measurements, or via equations of state. The latter two methods, however, are expensive and time-consuming and require complex calculations. Therefore, it is necessary to develop an accurate and reliable model for the determination of petroleum fluid’s physical properties. In this paper, a soft-computing approach is employed to develop efficient models for the calculation of bubble point pressure and oil formation volume factor properties. In pursu...

Precipitation of asphaltene, which is a complex hydrocarbon mixture, causes serious problems duri... more Precipitation of asphaltene, which is a complex hydrocarbon mixture, causes serious problems during petroleum production. Some problems associated with precipitation of asphaltene includes reduced oil recovery and relative permeabilities, blockage of rock pores, and reduction of flow rate. There is a number of issues (cost, time, and difficulty and accuracy of measurements) with regards to laboratory measurements and therefore it is important to develop reliable models to predict the phase behaviour of asphaltene precipitation. In this study, accurate models were developed using gene expression programming (GEP), decision tree (DT), and least squares support vector machine (LSSVM) methodologies for the determination of asphaltene precipitation from Iranian crude oil. To this end, molecular weight of precipitant (n-alkane), temperature, and ratio of precipitant (n-alkane) to oil dilution are considered as input variables for estimating the amount of precipitated asphaltene. The resul...

The viscosity of crude oil is an important parameter governing fluid flow in both porous media an... more The viscosity of crude oil is an important parameter governing fluid flow in both porous media and pipelines. The experimental measurement of reservoir oil viscosity is time consuming, difficult, and costly. Therefore, it is necessary to develop reliable models to determine viscosity. In this study, three models for dead, saturated, and under-saturated reservoir oils viscosities were developed, based on the gene expression programming (GEP) computational scheme. A dataset comprising more than 1000 sets of experimental pressure-volume-temperature (PVT) measurements drawn from Iranian oil fields were utilized in the model development. The dataset contains variables, which are regarded as significant and identifiable, namely, the gravity of oil, reservoir temperature, solution gas oil ratio, and bubble point pressure. The models developed are compared to a number of empirically-derived correlations. A comparison of results, using the GEP-based models for dead, saturated, and undersatur...

Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles, 2021

One of the promising applications of clathrate/gas hydrates is the transport and storage of natur... more One of the promising applications of clathrate/gas hydrates is the transport and storage of natural gas. Semi-clathrate hydrates have received more attention due to milder pressure/temperature stability conditions compared to ordinary clathrate hydrates. The most commonly reported semi-clathrate hydrates are formed from a combination of gas + water + quaternary ammonium salts. In this work, a total of 53 equilibrium data for semi-clathrate hydrates of methane + TetraButylAmmonium Bromide (TBAB)/TetraButylAmmonium Acetate (TBAA) aqueous solutions were experimentally measured. For TBAB, three concentrations including 0.0350, 0.0490, and 0.1500 mass fractions were used. For TBAA, a solution with a 0.0990 mass fraction was used. Additionally, the modified Chen–Guo model was applied to calculate the hydrate phase equilibrium conditions of methane + TBAB/TBAA aqueous solutions. The model can accurately calculate the aforementioned semi-clathrate hydrate phase equilibrium conditions with t...

Petroleum Science, 2020

It is necessary to understand all the prerequisites, which result in gas hydrate formation for sa... more It is necessary to understand all the prerequisites, which result in gas hydrate formation for safe design and control of a variety of processes in petroleum industry. Thermodynamic hydrate inhibitors (THIs) are normally used to preclude gas hydrate formation by shifting hydrate stability region to lower temperatures and higher pressures. Sometimes, it is difficult to avoid hydrate formation and hydrates will form anyway. In this situation, kinetic hydrate inhibitors (KHIs) can be used to postpone formation of gas hydrates by retarding hydrate nucleation and growth rate. In this study, two kinetic parameters including natural gas hydrate formation induction time and the rate of gas consumption were experimentally investigated in the presence of monoethylene glycol (MEG), L-tyrosine, and polyvinylpyrrolidone (PVP) at various concentrations in aqueous solutions. Since hydrate formation is a stochastic phenomenon, the repeatability of each kinetic parameter was evaluated several times ...

Journal of Petroleum Exploration and Production Technology, 2020

The pressure drop around the well in the production from a gas condensate reservoir causes the fo... more The pressure drop around the well in the production from a gas condensate reservoir causes the formation of condensate in the area before it reaches the well and surface space. This condensate and occasionally water in the porous medium can block the well and create an additional pressure drop. Studies show that the chemical treatment of this area eliminates the problem by altering the reservoir rock wettability toward a moderate and strong gasphilicity. For this purpose, fluoropolymers-, fluorosurfactants-, and fluorochemicals-coated nanoparticles can be used. In this work, we have studied two types of fluoride gas namely R134A and R404A, which are widely used in refrigeration industry as refrigerant gases, perfumery, and industrial detergents. The basis of this study was the aging of rock samples in thin sections and plugs in these two gases at different pressures above the critical pressures of them at 70 °C at different times and then conducting the contact angle experiments by ...

Petroleum Science, 2020

The pressure drop during production in the near-wellbore zone of gas condensate reservoirs causes... more The pressure drop during production in the near-wellbore zone of gas condensate reservoirs causes condensate formation in this area. Condensate blockage in this area causes an additional pressure drop that weakens the effective parameters of production, such as permeability. Reservoir rock wettability alteration to gas-wet through chemical treatment is one of the solutions to produce these condensates and eliminate condensate blockage in the area. In this study, an anionic fluorinated surfactant was synthesized and used for chemical treatment and carbonate rock wettability alteration. The synthesized surfactant was characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis. Then, using surface tension tests, its critical micelle concentration (CMC) was determined. Contact angle experiments on chemically treated sections with surfactant solutions and spontaneous imbibition were performed to investigate the wettability alteration. Surfactant adsorption on ...

Oil & Gas Sciences and Technology – Revue d’IFP Energies nouvelles, 2018

Polymers applications have been progressively increased in sciences and engineering including che... more Polymers applications have been progressively increased in sciences and engineering including chemistry, pharmacology science, and chemical and petroleum engineering due to their attractive properties. Amongst the all types of polymers, partially Hydrolyzed Polyacrylamide (HPAM) is one of the widely used polymers especially in chemistry, and chemical and petroleum engineering. Capability of solution viscosity increment of HPAM is the key parameter in its successful applications; thus, the viscosity of HPAM solution must be determined in any study. Experimental measurement of HPAM solution viscosity is time-consuming and can be expensive for elevated conditions of temperatures and pressures, which is not desirable for engineering computations. In this communication, Multilayer Perceptron neural network (MLP), Least Squares Support Vector Machine approach optimized with Coupled Simulated Annealing (CSA-LSSVM), Radial Basis Function neural network optimized with Genetic Algorithm (GA-R...