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Improving Temperature Stability of Drilling Fluids Polymers Using Nano Particles
,
M.Sc. Thesis
Sharif University of Technology
;
Ghotbi, Siroos
(Supervisor)
Abstract
Water base drilling fluids are the most common drilling fluids in oil and gas operations and biopolymers are the requisite additives used in such kind of fluids frequently. Unfortunately, at harsh conditions of HPHT the polymers undergo thermal degradation which cause serious loss in fluid rheological and filtration properties. Accordingly, this will induce operational pitfalls and tremendous cost. The power of economy along with environmental regulations force us to search for reasonable chemically benign additives to fulfill this need. Nanoparticles are the most promising additives proposed in this study to address this challenge. Regarding their unique exclusive properties, they are able...
Integrated Geomechanical Modeling of Casing Failure; From Lab to Simulation
, Ph.D. Dissertation Sharif University of Technology ; Pak, Ali (Supervisor) ; Shad, Saeed (Co-Supervisor)
Abstract
Casing failure is one of the mainly problems of hydrocarbon fields that may cause wells out of service and impose heavy costs on oil companies. There exist many theories that may cause casing failure including: the plastic behavior of surrounding formations, the effects of reservoir depletion, over-pressured formations, weak cementing operations, fault activation, and local stresses applied on casing. In salt-rich formations, creep behavior can be the main cause of casing failure, too.The purpose of this study is to evaluate the causes affecting casing failure via experimental studies and numerical simulation with the focus on the conditions governing south-west Iranian oil fields, where the...
Wettability Alteration of Reservoir Rocks to Super Gas-Wet Condition Using Nanocomposite by Applying Contact Angle Measurement for Gas-Crude Oil System
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossien (Supervisor) ; Fatemi, Mobeen (Supervisor) ; Esmaeilzadeh, Pouriya (Co-Supervisor)
Abstract
Today, increasing the productivity of reservoirs is more important than in the past, while the use of nanoparticles to change the wettability of rock and increase the recovery factor from the reservoir has been considered by many researchers. Despite previous studies on the use of nanoparticles to change the wettability of rock to gas-wet, the use of nanocomposites with super gas-wet at high temperature and pressure in the crude oil-gas system has rarely been considered. In this research, several nanocomposites with different structures have been synthesized in the laboratory and nanofluids with different formulations have been used to coat the rock thin sections and measure droplet contact...
Experimental Investigation of the Effect of Pressure and Gas Composition on the Interfacial Behavior of Gas/Oil System under High Pressure High Temperature Conditions
, M.Sc. Thesis Sharif University of Technology ; Fatemi, Mobeen (Supervisor) ; Ghazanfari, Mohammad Hossein (Co-Supervisor)
Abstract
Gas injection process is one of the main methods to increase the hydrocarbon reservoirs. Minimum Miscibility pressure is a key parameter that controls the efficiency of the gas injection process. It depends on the temperature, the composition of the injected gas and the composition of the reservoir fluids. In this study, the interfacial tension of the live oil-gas system of one of the reservoirs of southwestern Iran was obtained by analyzing the Pendant drop method at 225 ° F and different pressures, and then by using the Vanishing Interfacial Tension method, the Minimum Miscibility Pressure has been computed .In this study, pure and base gases such as nitrogen, methane and injection gas of...
Experimental and modelling investigations of asphaltene precipitation during pressure depletion and gas injection operations
, Article Petroleum Science and Technology ; Vol. 32, issue. 15 , August , 2014 , pp. 1868-1875 ; ISSN: 10916466 ; Alizadeh, A ; Afshari, S ; Kharrat, R ; Ghazanfari, M ; Sharif University of Technology
Abstract
Asphaltene precipitation problems manifest themselves in different stages of oil reservoirs production. Experimental and modeling investigations are, therefore, employed as promising tools to assist in predictions of asphaltene precipitation problems and selection of proper production facilities. This study concerns experimental and modeling investigations of asphaltene precipitation during natural production and gas injection operations for a heavy Iranian crude oil at reservoir conditions. First, with design and performance of high pressure-high temperature experiments, asphaltene precipitation behavior is comprehensively investigated; the effects of pressure and temperature are fully...
Precipitated asphaltene amount at high-pressure and high-temperature conditions
, Article Energy and Fuels ; Vol. 28, Issue. 3 , 2014 , pp. 1596-1610 ; ISSN: 08870624 ; Panuganti, S. R ; Taghikhani, V ; Pishvaie, M. R ; Chapman, W. G ; Sharif University of Technology
Abstract
In the upstream asphaltene flow assurance community, both academics and industries are actively involved to predict the asphaltene deposit profile in wellbores and pipelines. Essential information for such a study is the amount of asphaltenes that can precipitate and, hence, deposit. In this work, the perturbed chain form of the statistical associating fluid theory (PC-SAFT) is applied to predict the asphaltene precipitation onset condition as well as the amount of precipitate under pressure depletion and high-pressure and high-temperature gas injection conditions. Previous PC-SAFT asphaltene studies in crude oil required the compositional data for both flashed gas and flashed liquid. This...
Investigating the effects of temperature, pressure, and paraffin groups on the N2 miscibility in hydrocarbon liquids using the interfacial tension measurement method
, Article Industrial and Engineering Chemistry Research ; Volume 52, Issue 29 , 2013 , Pages 9851-9857 ; 08885885 (ISSN) ; Riazi, M ; Escrochi, M ; Ayatollahi, S ; Sharif University of Technology
2013
Abstract
In this study, interfacial tension measurement (IFT) is utilized to assess the impact of temperature, pressure, and paraffin type on a nitrogen injection process as an efficient enhanced oil recovery method. The pure and equilibrium densities of oil in contact with nitrogen are examined to find IFT behavior and gas solubility in oil. The minimum miscible pressure (MMP) of different systems has been measured using the vanishing interfacial tension technique. The experimental results show that IFT decreases linearly with pressure, with two different slopes. The results indicate that IFT values decrease linearly with temperature at different pressure conditions. The obtained IFT values for...
The effects of nano Mgo on physical and mechanical properties of Al 2O3-SiC composites
, Article Journal of Ceramic Science and Technology ; Volume 3, Issue 1 , 2012 , Pages 29-34 ; 21909385 (ISSN) ; Surani, F ; Abdizadeh, H ; Baharvandi, H. R ; Sharif University of Technology
2012
Abstract
In this research, the effects of nano-sized MgO in Al2O 3-SiC composites were investigated. The overall changes in the density and mechanical properties of sintered samples (hardness, bending strength and toughness) were evaluated. After mixing, drying and uniaxial compaction of the powders, they were first heat-treated at low temperature in an electric furnace to remove any residuals. They were then heat-treated at high temperature (1700 °C) inside a graphite furnace in argon atmosphere for sintering (at normal and high pressure). The content of MgO in the Al 2O3-10 vol% SiC composite was 0, 500, 1000, and 1500 ppm. Thefracture toughness(KIC)of sintered composite with 10...
Probabilistic safety assessment of a UF 6 production process
, Article Advances in Safety, Reliability and Risk Management - Proceedings of the European Safety and Reliability Conference, ESREL 2011 ; 2012 , Pages 1384-1389 ; 9780415683791 (ISBN) ; Sharif University of Technology
2012
Abstract
Application of Probabilistic Safety Assessment (PSA) to a Uranium hexafluoride (UF 6) production process is presented in this paper. The process is constituted from three main units: UF 4 conversion to UF 6, condensation of produced UF 6 gas and tail gas treatment. Radioactive gas is present in all parts of the process and occurrence of high pressure or high temperature in the process equipments may lead to radioactive release to workplace and environment. The work is mainly based on PSA experience in nuclear power plants. Accordingly for the process, eight group of Initiating Events (IE) that lead to UF 6 gas release have been identified using HAZOP study. For each IE, based on related...
An experimental investigation of asphaltene precipitation during natural production of heavy and light oil reservoirs: The role of pressure and temperature
, Article Petroleum Science and Technology ; Volume 29, Issue 10 , 2011 , Pages 1054-1065 ; 10916466 (ISSN) ; Nakhli, H ; Kharrat, R ; Ghazanfari, M. H ; Sharif University of Technology
Abstract
Many oil reservoirs encounter asphaltene precipitation as a major problem during natural production. In spite of numerous experimental studies, the effect of temperature on asphaltene precipitation during pressure depletion at reservoir conditions is still obscure in the literature. To study their asphaltene precipitation behavior at different temperatures, two Iranian light and heavy live oil samples were selected. First, different screening criteria were applied to evaluate asphaltene instability of the selected reservoirs using pressure, volume, and temperature data. Then, a high pressure, high temperature filtration (HPHT) setup was designed to investigate the asphaltene precipitation...
The role of co-solvents in improving the direct transesterification of wet microalgal biomass under supercritical condition
, Article Bioresource Technology ; Volume 193 , October , 2015 , Pages 90-96 ; 09608524 (ISSN) ; Vossoughi, M ; Pazuki, G ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
In this research, direct conversion of wet algal biomass into biodiesel using supercritical methanol was studied. In this process, microalgal lipids simultaneously was extracted and converted to biodiesel under high pressure and temperature conditions without using any catalyst. Several experiments have been performed to optimize the methanol amount and it has been revealed that the best performance was achieved by using methanol/wet biomass ratio of 8:1. The effect of using various co-solvents in increasing the efficiency of the supercritical process was investigated. It has been shown that hexane was the most effective co-solvent and its optimal ratio respect to wet biomass was 6:1. The...
The Effects of Various Parameters on Wellbore Stability During Drilling Through Shale Formations
, Article Petroleum Science and Technology ; Volume 33, Issue 12 , 2015 , Pages 1275-1285 ; 10916466 (ISSN) ; Ghotbi, C ; Pishvaie, M. R ; Sharif University of Technology
Taylor and Francis Inc
2015
Abstract
Field evidence indicates that the thermal and chemical regimes in wellbore considerably affect the wellbore stability. This study presents a general coupled model for transport of solute, solvent and heat including their combined effects on the wellbore stability. Optimization of drilling fluid parameters is crucial for wellbore stability analysis particularly in high pressure-high temperature environments. The coupled effects of chemical potential and temperature gradients on fluid flow significantly change the pore pressure and stress around a borehole. The effects of various parameters such as mud weight, solute concentration gradient, shale properties, and temperature gradient on...
Dynamic modeling and optimization of asphaltene deposition in reservoir rocks using genetic algorithm
, Article 72nd European Association of Geoscientists and Engineers Conference and Exhibition 2010: A New Spring for Geoscience. Incorporating SPE EUROPEC 2010 ; Volume 6 , 2010 , Pages 4291-4295 ; 9781617386671 (ISBN) ; Kharrat, R ; Hemmatfar, V ; Ghotbi, C ; Sharif University of Technology
Society of Petroleum Engineers
2010
Abstract
Asphaltene deposition is a problematic challenge for oil production. Changes in key parameters like pressure and fluid composition during natural depletion and different gas injection scenarios may result in asphaltene precipitation and deposition. In this work, a model is developed by application of mass balance equations, momentum equation, asphaltene deposition and permeability reduction models. An algorithm is developed to perform iterative procedure to solve the numerical equations that contains highly coupled variables. Indeed, an equation is introduced to calculate the saturation of the precipitated asphaltene phase. Model parameters were determined by genetic algorithm which is a...
Kinetics of asphaltene aggregation phenomena in live oils
, Article Journal of Molecular Liquids ; Volume 222 , 2016 , Pages 359-369 ; 01677322 (ISSN) ; Rashidi, F ; Ghazanfari, M. H ; Mousavi Dehghani, S. A ; Sharif University of Technology
Elsevier
Abstract
The thorough knowledge of the asphaltene aggregation phenomena and pressure/temperature related kinetics is helpful for accurate prediction/control of the asphaltene issues in all facets of petroleum production/processing. However, characterizing the asphaltene aggregation phenomena in live oils at high pressure-high temperature conditions is not well discussed in the available literature. In this work, the asphaltene aggregation phenomena as well as the kinetics of aggregation at different levels of pressure and temperature are investigated in light and heavy live oils using high pressure microscope. The results are presented and discussed in terms of asphaltene onset pressure, aggregates...
An improvement of thermodynamic micellization model for prediction of asphaltene precipitation during gas injection in heavy crude
, Article Fluid Phase Equilibria ; Volume 308, Issue 1-2 , September , 2011 , Pages 153-163 ; 03783812 (ISSN) ; Masihi, M ; Ghazanfari, M. H ; Kharrat, R ; Sharif University of Technology
Abstract
Thermodynamic micellization model is known as an appropriate approach for prediction of asphaltene precipitation. However, the reliability (i.e. accuracy) of this model for whole range of pressure or injected gas mole percent must be checked. In practice, the accuracy can be improved by using a suitable characterization method. In this research, a computer code for implementing the thermodynamic micellization model has been developed. Having used this program, we make the prediction of asphaltene precipitation by using data reported in the literature as well as the experimental data obtained from high pressure, high temperature asphaltene precipitation experiments under gas injection...
Modeling of asphaltene aggregation phenomena in live oil systems at high pressure-high temperature
, Article Fluid Phase Equilibria ; Volume 423 , 2016 , Pages 55-73 ; 03783812 (ISSN) ; Rashidi, F ; Mousavi Dehghani, S. A ; Ghazanfari, M. H ; Sharif University of Technology
Elsevier
Abstract
In spite of the development of different experimental methods and theoretical models devoted to understand and predict the asphaltene behavior in dead/model oils, the asphaltene aggregation phenomena in live oil systems at high pressure-high temperature conditions has been grossly missing in the available literature. In this study, a population balance model with geometric scaling approach is proposed to simulate the asphaltene aggregates growth in time for live oil systems. Appropriate collision kernels are incorporated to describe the aggregation mechanisms taking into account the effect of pressure, temperature and oil characteristics. In modeling of the asphaltene aggregation phenomena...
On the effect of temperature on precipitation and aggregation of asphaltenes in light live oils
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 9 , 2016 , Pages 1820-1829 ; 00084034 (ISSN) ; Rashidi, F ; Mousavi Dehghani, S. A ; Ghazanfari, M. H ; Sharif University of Technology
Wiley-Liss Inc
Abstract
Asphaltene precipitation and deposition is a serious issue in all facets of petroleum production and processing. Despite the numerous experimental efforts concerning asphaltenes, the effect of temperature on asphaltene precipitation and aggregation in live oils remains an elusive and controversial subject in the available literature. In this work, a series of high pressure-high temperature depressurization experiments were designed to assess the effect of temperature on asphaltene precipitation and aggregation in light live oils. Asphaltene related experiments were performed using a high pressure microscope and high pressure-high temperature filtration setup on a light live oil with a low...
The Role of Carbon Nanotubes in Improving Thermal Stability of Polymeric Fluids: Experimental and Modeling
, Article Industrial and Engineering Chemistry Research ; Volume 55, Issue 27 , 2016 , Pages 7514-7534 ; 08885885 (ISSN) ; Ghotbi, C ; Tahmasbi, K ; Ghazanfari, M. H ; Sharif University of Technology
American Chemical Society
2016
Abstract
At harsh conditions of high pressure high temperature (HPHT), polymers undergo thermal degradation leading to serious loss in fluid rheological and filtration properties. Nanoparticles are the most promising additives proposed to address this challenge. The stability of nanofluids is perused from various facets including rheological and filtration properties, shale stability, and zeta potential. The presence of nanoparticles could amazingly reduce the filtration at high temperatures even by 95%, and it also had a conspicuous effect on shale stability, thermal conductivity, and zeta potential. Experimental data were fit to rheological models to determine the best models describing the...
Fractal analysis of asphaltene aggregation phenomena in live oils at elevated pressure and temperature
, Article Particulate Science and Technology ; 2016 , Pages 1-9 ; 02726351 (ISSN) ; Rashidi, F ; Mousavi Dehghani, S. A ; Ghazanfari, M. H ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
In this work, high-pressure microscopy technique was used to measure the size and fractal dimension of asphaltene aggregates formed in different live oil samples at elevated pressures and temperatures. It was found that the asphaltene aggregates in live oil samples are irregular fractal-like structures with pressure−temperature-dependent fractal dimensions. By monitoring the variation of the fractal dimension and size of the asphaltene aggregates with pressure and temperature, the mechanisms responsible for asphaltene aggregation process at elevated pressures and temperatures can be well predicted. The range of fractal dimension of asphaltene aggregates in live oils is similar to that...
Formation mechanism of bead-chain-like ZnO nanostructures from oriented attachment of Zn/ZnO nanocomposites prepared via DC arc discharge in liquid
, Article Materials Science in Semiconductor Processing ; Volume 72 , 2017 , Pages 128-133 ; 13698001 (ISSN) ; Poursalehi, R ; Naseri, N ; Sharif University of Technology
Abstract
Bead-chain-like ZnO nanoparticles (NPs) formed in colloidal solution from oriented attachment (OA) of spherical nanoparticles. Arc discharge in liquid is a cost-effective method for quick mass production of nanostructured materials without considerable environmental footprints. Applying voltage across two zinc rods as electrodes, which were immersed in water cause explosion of electrodes and plasma generation. Zn/ZnO nanocomposites produced by interaction of different active species in high-pressure and high-temperature plasma at the solid-liquid interface. Different sized nanoparticles with diameters of 26, 35, 40 and 60 nm at applied discharge currents of 150, 100, 50 and 20 A...