Loading...
Search for:
oil-fields
0.037 seconds
Total 111 records
Investigation of the effect of water based nano-particles addition on hysteresis of oil and-water relative permeability curves
, Article Society of Petroleum Engineers - SPE International Oilfield Nanotechnology Conference 2012 ; June , 2012 , p. 267-277 ; Masihi, M ; Ghazanfari, M. H ; Sherafati, M ; Mashayekhi, L ; Sharif University of Technology
Abstract
It has been shown that one kind of poly silicon particles with sizes ranging from 10-500 nm, can be used in oilfields to enhance the oil recovery of water injection by 15-20%. The contributing mechanism might be reducing the interfacial tension which appears through improving relative permeability of the oil-phase. However, fundamental understanding of how hysteretic behavior of relative permeability curves affected by nanosilica particles remains a topic of debate in the literature. In this study, water as well as water dispersed nanosilica particles floods was performed on sandstone rock sample saturated by light crude oil supplied from one of Iranian oil reservoir, and the relative...
Prediction of the aqueous solubility of BaSO4 using pitzer ion interaction model and LSSVM algorithm
, Article Fluid Phase Equilibria ; Vol. 374, issue , July , 2014 , p. 48-62 ; ISSN: 03783812 ; Shokrollahi, A ; Jamialahmadi, M ; Ghazanfari, M. H ; Bahadori, A ; Zendehboudi, S ; Sharif University of Technology
Abstract
Deposition of barium sulfate (or BaSO4) has already been recognized as a devastating problem facing process industries and oilfield operations, mainly owing to its low solubility in aqueous solutions. Predicting and also preventing the overall damage caused by BaSO4 precipitation requires a profound knowledge of its solubility under different thermodynamic conditions. The main aim of this study is to develop a solubility prediction model based on a hybrid of least squares support vector nachines (LSSVM) and coupled simulated annealing (CSA) aiming to predict the solubility of barium sulfate over wide ranges of temperature, pressure and ionic compositions. Results indicate that predictions of...
Comparison of wellbore stability of UBD in the case of laser drilling and conventional operation
, Article 76th European Association of Geoscientists and Engineers Conference and Exhibition 2014: Experience the Energy - Incorporating SPE EUROPEC 2014 ; 2014 , Pages 1736-1740 ; ISBN: 9781632666949 ; Nakhaee, A ; Koohian, A ; Irawan, S ; Habibpour, M ; Shahvar, M ; Sharif University of Technology
Abstract
In recent years, growing interest in underbalanced drilling has resulted in the rapid development of its associated equipment technology, practices, and procedures. Underbalanced drilling is used to avoid lost circulation, formation damage, and decreasing weight on bit. However, the risk of wellbore collapse due to lake of hydrostatic mud pressure is high; therefore, using good geo-mechanical model may avoid wellbore instability problems. In order to evaluate the potential for wellbore instability, it is necessary to use an elastoplastic model to compute the stresses and strains around the bore hole. Furthermore, it should be mentioned that the laser drilling process depends extremely on the...
Optimization of gas allocation to a group of wells in gas lift in one of the Iranian oil fields using an efficient hybrid genetic algorithm (HGA)
, Article Petroleum Science and Technology ; Volume 31, Issue 9 , 2013 , Pages 949-959 ; 10916466 (ISSN) ; Ghotbi, C ; Aminshahidy, B ; Sharif University of Technology
2013
Abstract
A hybrid genetic algorithm (HGA) was introduced to allocate optimum amount of gas. This method was applied to a group of wells in gas lift in the case of availability limited amount of gas. For testing the ability of the proposed HGA, the results of this work with those of previous works in a field with six wells were compared. Then for an Iranian southern west oil field with nine wells, gas allocation is performed using different amount of available gas. The results show that the introduced method (HGA) is very efficient tool in gas allocation issue
Integrating constrained random waves in endurance time analysis of offshore structures subjected to sea waves
, Article Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE, 1 July 2012 through 6 July 2012 ; Volume 2 , July , 2012 , Pages 677-684 ; 9780791844892 (ISBN) ; Estekanchi, H ; Zeinoddini, M ; Golestani, M ; Sharif University of Technology
2012
Abstract
This paper introduces a novel methodology for design and assessment of offshore structures exposed to irregular sea waves. For this, Constrained NewWave (CNW) is integrated with the Endurance Time Analysis (ETA) methodology, which is basically developed for the performance based analysis of onshore structures to earthquake loads. In this approach, the offshore structure is simulated in time-domain under a set of calibrated intensifying wave functions. They are devised to represent a gradually increasing roughness of the sea state by time. A performance index such as base shear, drift or stress in a critical structural members are monitored until they reach to a predefined maximum value. A...
Herschel-Bulkley rheological parameters of lightweight colloidal gas aphron (CGA) based fluids
, Article Chemical Engineering Research and Design ; Volume 93 , 2015 , Pages 21-29 ; 02638762 (ISSN) ; Arabloo, M ; Ghazanfari, M. H ; Rashtchian, D ; Sharif University of Technology
Institution of Chemical Engineers
2015
Abstract
The proper understanding of rheological characteristics of CGA based fluids is of crucial importance in determining the performance of the fluid, in order to maintain the most effective fluid properties for safe, efficient, and economical drilling operation. This paper presents a concise investigation on the effect of concentration of the three main components of a novel environmentally friendly lightweight CGA based drilling fluid, i.e., xanthan gum biopolymer, starch, and biosurfactant, to the Herschel-Bulkley rheological model parameters. The three parameters of Herschel-Bulkley model, i.e., yield stress, fluid consistency, and fluid flow index were calculated by fitting the experimental...
Near wellbore thermal effects in a tight gas reservoir: Impact of different reservoir and fluid parameters
, Article Journal of Unconventional Oil and Gas Resources ; Volume 16 , 2016 , Pages 1-13 ; 22133976 (ISSN) ; Holmgrün, C ; Calogirou, A ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
Temperature changes in and around the wellbore could lead to significant well performance and flow assurance issues. Despite its importance, near wellbore temperature change due to gas production and its importance on well performance is not well understood. Reduction of temperature in the near well bore section, could potentially lead to hydrate formation and as a result reduction of well performance. This work is aimed at evaluating the thermal behaviour in the near wellbore region of a low to tight permeability gas reservoir (ranging between 0.02 and 10 mD) during its natural depletion. The study is conducted by using a thermal-compositional simulator. The process required to simulate...
Study the effect of connectivity between two wells on secondary recovery efficiency using percolation approach
, Article 15th European Conference on the Mathematics of Oil Recovery, ECMOR 2016, 29 August 2016 through 1 September 2016 ; 2016 ; 9462821933 (ISBN); 9789462821934 (ISBN) ; Masihi, M ; King, P. R ; Gago, P. A ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2016
Abstract
Estimating available hydrocarbon to be produced during secondary oil recovery is an ongoing activity in field development. The primary plan is normally scheduled during early stage of field's life through master development plan studies. During this period, due to the lake of certain data, estimation of the field efficiency is usually based on rules of thumb and not detailed field characterization. Hence, there is a great motivation to produce simpler physically-based methodologies. The minimum necessity inputs of percolation approach make it a useful tool for foration performance prediction. This approach enables us to attain a better assessment of the efficiency of secondary recovery...
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...
A novel model for wellbore stability analysis during reservoir depletion
, Article Journal of Natural Gas Science and Engineering ; 2016 , Pages 935-943 ; 18755100 (ISSN) ; Volume 35, Issue Part A ; Hassani, A. H ; Al Ajmi, A. M ; Heydari, H ; Sharif University of Technology
Elsevier B.V
Abstract
It is not common to build a geomechanical model for depleted reservoirs as logging and coring are costly and time consuming in such reservoirs. On the other hand, in regular analysis of wellbore stability, the effect of time is completely ignored. As a result, with time there will be some errors in the evaluation of wellbore stability in depleted reservoirs. In order to determine the optimum wellbore trajectory during the reservoir life, it is necessary to have a model which can estimate the rock properties based on the first full logging suite and also consider the depletion effect. In this study, a novel model is proposed which combines a mechanical earth model, borehole circumferential...
Modeling and simulation of oil well stimulation by high power ultrasonic irradiation
, Article Acta Acustica united with Acustica ; Volume 103, Issue 3 , 2017 , Pages 411-420 ; 16101928 (ISSN) ; Ahmad Ramazani, S. A ; Jamshidi, S ; Moghaddam, A. K ; Sharif University of Technology
S. Hirzel Verlag GmbH
2017
Abstract
Ultrasonic waves have been extensively used in many industrial applications including clean devices, pipes and vessels. A clear extension of this usage is the removal of wellbore contaminants by exposing it to high-power ultrasonic waves. In this paper, a mathematical model for ultrasonic propagation through the porous medium around the wellbore is presented. The equations of wave propagation are written in a cylindrical coordinate according to Biot theory and the induced stress in the rock are calculated at each point using finite difference approach Comparison of imposed local stresses with adhesion forces between scales and rock, the properties of ultrasonic transducer, such as frequency...
The effect of dispersed phase salinity on water-in-oil emulsion flow performance: A micromodel study
, Article Industrial and Engineering Chemistry Research ; Volume 56, Issue 15 , 2017 , Pages 4549-4561 ; 08885885 (ISSN) ; Ayatollahi, S ; Rezaei, N ; Masihi, M ; Sharif University of Technology
American Chemical Society
2017
Abstract
In this work, the effect of brine salinity on water-in-oil emulsion flow performance in porous media is studied as it imposes a significant challenge to oil production in the petroleum industry. A crude oil sample from an Iranian oilfield and synthetic brine with different salinities (40-140 g/L salt) are used. The results show that the emulsion viscosity and interfacial tension increase slightly with salinity, while they do not considerably affect the flow behavior. The emulsion stability analysis shows that larger w/o emulsion droplets are formed for higher brine salinity, which potentially block more pore spaces through straining and interception mechanisms. This phenomenon resulted in...
Integrated seismic attributes to characterize a widely distributed carbonate clastic deposit system in khuzestan province, SW Iran
, Article Journal of Geophysics and Engineering ; Volume 6, Issue 2 , 2009 , Pages 162-171 ; 17422132 (ISSN) ; Nabi Bidhendi, M ; Javaherian, A ; Pishvaie, M. R ; Sharif University of Technology
2009
Abstract
Integrated seismic attributes, coherency, acoustic impedance (AI), lambda-rho (λρ) and mu-rho (μρ), were used to delineate and to characterize a complex regional channel deposition system in a carbonate reservoir interval in the upper part of the Sarvak Formation. The study area incorporates three adjacent oil fields in SW Iran (Khuzestan Province) covered by three individual 3D seismic surveys having a total area of about 2800 km 2. We generated a regional horizon-based coherency cube using these three seismic surveys. This revealed a carbonate clastic deposition channelling system over the entire study area. We characterized this channel deposition system in agreement with regional...
FEMA approaches in seismic assessment of jacket platforms (case study: Ressalat jacket of Persian gulf)
, Article Journal of Constructional Steel Research ; Volume 65, Issue 10-11 , 2009 , Pages 1979-1986 ; 0143974X (ISSN) ; Tabeshpour, M. R ; Komachi, Y ; Sharif University of Technology
2009
Abstract
The assessment of existing platforms under past environmental (wave, wind, current and etc.) loads and probable future loads (earthquake) is a relatively new process and has not yet been standardized as the design has. This lack of standardization creates some difficulty in establishing performance requirements which must be developed depending upon the risks (i.e., hazards, exposures and consequences) associated with the future operation of the platform. The present criteria of the offshore structure standards for seismic assessment can be improved using Building prestandards. Recently some documents such as FEMA-356 and ATC-40 are developed for seismic assessment of buildings. However...
Isolation and screening of Bacillus subtilis MJ01 for MEOR application: biosurfactant characterization, production optimization and wetting effect on carbonate surfaces
, Article Journal of Petroleum Exploration and Production Technology ; Volume 9, Issue 1 , 2019 , Pages 233-245 ; 21900558 (ISSN) ; Ganji Azad, E ; Deihimi, T ; Niazi, A ; Ayatollahi, S ; Sharif University of Technology
Springer Verlag
2019
Abstract
The bacterial strain MJ01 was isolated from stock tank water of one of the Iranian south oil field production facilities. The 16S rRNA gene of isolate, MJ01, showed 99% similarity to Bacillus subtilis. The results revealed that biosurfactant produced by this strain was lipopeptide-like surfactin based on FTIR analysis. Critical micelle concentration of produced surfactin in distilled water was 0.06 g/l. Wettability study showed that at zero salinity surfactin can change original oil-wet state to water-wet state, but in seawater salinity it cannot modify the wettability significantly. To utilize this biosurfactant in ex situ MEOR process, economical and reservoir engineering technical...
Coupled hydro-mechanical analysis of underground gas storage at Sarajeh field, Qom formation, Iran
, Article Journal of Natural Gas Science and Engineering ; Volume 92 , 2021 ; 18755100 (ISSN) ; Shad, S ; Zivar, D ; Razaghi, N ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Production or injection of fluids from/in an underground storage site causes variations of pore pressure and stress states. These fluctuations significantly affect implications for hydraulic fracturing, wellbore integrity, top surface subsidence and heave, fault-reactivation, and stability of reservoir and caprock. Therefore, in order to keep optimal conditions during the process of gas injection and production, it is of paramount importance to have accurate estimates of the pore pressure. In this investigation, coupled fluid flow and geomechanical simulations, as well as rock mechanical tests, are performed on the Sarajeh field, Iran to investigate the geomechanical behavior of the Sarajeh...
Well Injectivity during CO2Geosequestration: A Review of Hydro-Physical, Chemical, and Geomechanical Effects
, Article Energy and Fuels ; Volume 35, Issue 11 , 2021 , Pages 9240-9267 ; 08870624 (ISSN) ; Bedrikovetsky, P ; Borazjani, S ; Mahani, H ; Sharif University of Technology
American Chemical Society
2021
Abstract
Deep saline aquifers are among the most favorable geological sites for short- and long-term carbon geosequestration. Injection of CO2 into aquifers causes various hydro-physical, chemical, and geomechanical interactions that affect the injectivity of wellbores. Despite the extensive research conducted on carbon capture and storage (CCS), there exists a lack of focus on the concept of injectivity. The present study aims to identify the gaps by reviewing the major factors contributing to CO2 injectivity in deep saline aquifers. Moreover, the existing analytical and numerical mathematical models to estimate maximum sustainable injection pressure and pressure build-up are critically reviewed....
Application of an improved harmony search algorithm in well placement optimization using streamline simulation
, Article Journal of Petroleum Science and Engineering ; Volume 78, Issue 3-4 , 2011 , Pages 664-678 ; 09204105 (ISSN) ; Aminshahidy, B ; Pishvaie, M. R ; Sharif University of Technology
2011
Abstract
Optimal well placement is a crucial step in efficient reservoir development process which significantly affects the productivity and economical benefits of an oil reservoir. However, it is a complex and challenging problem due to the different engineering, geological and economical variables involved. This leads to a very large number of potential scenarios that must be evaluated using numerical reservoir simulations. The key points in such an optimization process are using a fast function evaluation tool and development of an efficient and robust optimization algorithm that can find good solutions with a minimum required number of function evaluations. This study presents an approach that...
Experimental investigation of oily water treatment by membrane bioreactor
, Article Desalination ; Volume 250, Issue 2 , 2010 , Pages 598-600 ; 00119164 (ISSN) ; Mowla, D ; Vossoughi, M ; Hesampour, M ; Sharif University of Technology
Abstract
In this study a membrane bioreactor (MBR) has been studied experimentally for the treatment of oil field wastewater (produced water). This type of wastewater is characterised with relativity moderate to high amount of salt and oil. The normal bacteria which are growing in conventional activated sludge and MBR cannot withstand at these adverse conditions, therefore it is necessary to be adapted. In this study, different samples from sea sediment in Bushehr (south of Iran) were analysed and different groups of bacteria were isolated and adapted for surveying under high salinity conditions. The performance and efficiency of these bacteria in the degradation of model oil has been studied. The...
Application of decision tree, artificial neural networks, and adaptive neuro-fuzzy inference system on predicting lost circulation: A case study from Marun oil field
, Article Journal of Petroleum Science and Engineering ; Volume 177 , 2019 , Pages 236-249 ; 09204105 (ISSN) ; Talebkeikhah, M ; Agin, F ; Talebkeikhah, F ; Hasheminasab, E ; Sharif University of Technology
Elsevier B.V
2019
Abstract
One of the most prevalent problems in drilling industry is lost circulation which causes intense increase in drilling expenditure as well as operational obstacles such as well instability and blowout. The aim of this research is to develop smart systems for estimating amount of lost circulation making able to use appropriate prevention and remediation methods. To obtain this aim, a large data set were collected from 61 recently drilled wells in Marun oil field in Iran to be used for developing relevant models. After that, using the extracted data set consisting of 1900 data subset, intelligent prediction models including decision tree (DT), adaptive neuro-fuzzy inference systems (ANFIS),...