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Srdjan Nesic - One of the best experts on this subject based on the ideXlab platform.
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effect of incorporation of calcium into Iron Carbonate protective layers in co2 corrosion of mild steel
Corrosion, 2017Co-Authors: Saba Navabzadeh Esmaeely, David J Young, Bruce Brown, Srdjan NesicAbstract:The two dominant cationic species in reservoir brine are sodium (Na+) and calcium (Ca2+). Calcite (CaCO3) and siderite (FeCO3) are isostructural, thus Ca2+ incorporates readily into the hexagonal FeCO3 lattice, and vice versa. In aqueous carbon dioxide (CO2) solutions where both Ca2+ and ferrous Iron (Fe2+) are present (such as downhole gas reservoirs or deep saline aquifers after CO2 injection), inhomogeneous mixed metal Carbonates with the formula FexCayCO3 (x + y = 1) can form; their presence on steel has been hypothesized to lead to localized corrosion. During carbon steel corrosion experiments conducted in electrolytes containing high Ca2+ concentrations, inhomogeneous corrosion product layers with the composition FexCayCO3 (x + y = 1) were indeed observed, along with non-uniform corrosion. Determining relative molar fractions of Ca2+ and Fe2+ in FexCayCO3 is paramount to predicting the relative properties and stability of such mixed metal Carbonates. Using Bragg’s law and equations to relate interpl...
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effect of calcium on the formation and protectiveness of Iron Carbonate layer in co2 corrosion
Corrosion, 2013Co-Authors: Saba Navabzadeh Esmaeely, Yoonseok Choi, David J Young, Srdjan NesicAbstract:The effect of calcium (Ca2+) on the carbon dioxide (CO2) corrosion of mild steel was investigated in simulated saline aquifer envIronments (1 wt% sodium chloride [NaCl], 80°C, pH 6.6) with different concentrations of Ca2+ (10, 100, 1,000, and 10,000 ppm). Electrochemical methods (open-circuit potential [OCP]) and linear polarization resistance [LPR] measurements) were used to evaluate the corrosion behavior. Surface analysis techniques (scanning electron microscopy [SEM], energy-dispersive x-ray spectroscopy [EDS], and x-ray diffraction [XRD]) were used to characterize the morphology and identity the corrosion products. The results showed that with low concentrations of Ca2+ (10 ppm and 100 ppm), the corrosion rate decreased with time as a result of the formation of protective Iron Carbonate (FeCO3) and/or mixed Carbonate (FexCayCO3) (x + y = 1). However, the presence of high concentrations of Ca2+ (1,000 ppm and 10,000 ppm) resulted in the change of corrosion product from protective FeCO3 to non-protecti...
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effects of multiphase flow on internal co2 corrosion of mild steel pipelines
Energy & Fuels, 2012Co-Authors: Srdjan NesicAbstract:The focus in this paper is on the effects of multiphase flow on CO2 corrosion of mild steel pipelines. The significance of mass transfer in turbulent flow is discussed first: (i) when an increased rate of mass transfer of corrosive species, such as H+ ions, to the steel surface leads to an acceleration of the cathodic reactions and a higher corrosion rate and (ii) when an increased mass-transfer rate of the corrosion product, ferrous ions (Fe2+), away from the steel surface makes it harder to form protective ferrous Carbonate layers. The mechanical interaction of the flow with the pipe walls is discussed next, where the wall shear stress is often blamed for removal of protective surface layers, such as Iron Carbonate or inhibitor films. Using macroscopic as well as atomic scale measurements [atomic force microscopy (AFM)], it was found that it is very unlikely that truly protective surface layers can be removed by mechanical forces alone. The other multiphase flow effects on corrosion, such as the effect ...
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effect of h2s on the co2 corrosion of carbon steel in acidic solutions
Electrochimica Acta, 2011Co-Authors: Yoonseok Choi, Srdjan Nesic, Shiun LingAbstract:Abstract The objective of this study is to evaluate the effect of low-level hydrogen sulfide (H 2 S) on carbon dioxide (CO 2 ) corrosion of carbon steel in acidic solutions, and to investigate the mechanism of Iron sulfide scale formation in CO 2 /H 2 S envIronments. Corrosion tests were conducted using 1018 carbon steel in 1 wt.% NaCl solution (25 °C) at pH of 3 and 4, and under atmospheric pressure. The test solution was saturated with flowing gases that change with increasing time from CO 2 (stage 1) to CO 2 /100 ppm H 2 S (stage 2) and back to CO 2 (stage 3). Corrosion rate and behavior were investigated using linear polarization resistance (LPR) technique. Electrochemical impedance spectroscopy (EIS) and potentiodynamic tests were performed at the end of each stage. The morphology and compositions of surface corrosion products were analyzed using scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The results showed that the addition of 100 ppm H 2 S to CO 2 induced rapid reduction in the corrosion rate at both pHs 3 and 4. This H 2 S inhibition effect is attributed to the formation of thin FeS film (tarnish) on the steel surface that suppressed the anodic dissolution reaction. The study results suggested that the precipitation of Iron sulfide as well as Iron Carbonate film is possible in the acidic solutions due to the local supersaturation in regions immediately above the steel surface, and these films provide corrosion protection in the acidic solutions.
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effect of impurities on the corrosion behavior of co2 transmission pipeline steel in supercritical co2 water envIronments
Environmental Science & Technology, 2010Co-Authors: Yoonseok Choi, Srdjan Nesic, David J YoungAbstract:The corrosion property of carbon steel was evaluated using an autoclave under CO(2)-saturated water phase and water-saturated CO(2) phase with impurities (O(2) and SO(2)) at 80 bar CO(2) and 50 °C to simulate the condition of CO(2) transmission pipeline in the carbon capture and storage (CCS) applications. The results showed that the corrosion rate of carbon steel in CO(2)-saturated water was very high and it increased with adding O(2) in the system due to the inhibition effect of O(2) on the formation of protective FeCO(3). It is noteworthy that corrosion took place in the water-saturated CO(2) phase under supercritical condition when no free water is present. The addition of O(2) increased the corrosion rates of carbon steel in water-saturated CO(2) phase. The addition of 0.8 bar SO(2) (1%) in the gas phase dramatically increased the corrosion rate of carbon steel from 0.38 to 5.6 mm/y. This then increased to more than 7 mm/y with addition of both O(2) and SO(2). SO(2) can promote the formation of Iron sulfite hydrate (FeSO(3)·3H(2)O) on the steel surface which is less protective than Iron Carbonate (FeCO(3)), and it is further oxidized to become FeSO(4) and FeOOH when O(2) is present with SO(2) in the CO(2)-rich phase. The corrosion rates of 13Cr steel were very low compared with carbon steel in CO(2)-saturated water envIronments with O(2), whereas it was as high as carbon steel in a water-saturated CO(2) phase with O(2) and SO(2).
Anne Neville - One of the best experts on this subject based on the ideXlab platform.
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Iron Carbonate formation kinetics onto corroding and pre filmed carbon steel surfaces in carbon dioxide corrosion envIronments
Applied Surface Science, 2019Co-Authors: Richard Barker, Al I Shaaili, R A De Motte, D Burkle, Thibaut V J Charpentier, S M Vargas, Anne NevilleAbstract:Abstract This work investigates the Corrosion Layer Accumulation Rate (CLAR) of Iron Carbonate (FeCO3) onto X65 carbon steel in carbon dioxide containing envIronments using the direct method of corrosion layer mass gain measurement. Glass cell experiments were performed at 80 °C and pH 6.3 or 6.8 over a range of bulk FeCO3 saturation ratios using both actively corroding carbon steel and steel pre-filmed with FeCO3. The CLARs obtained from experiments using actively corroding samples displayed strong agreement with the most recently developed precipitation model by Sun and Nesic at high supersaturation for pH 6.3 and 6.8, but a disparity at low supersaturation for the solution at pH 6.8. The observed discrepancy was attributed to the significant difference in surface saturation ratio between the two conditions when the steel is actively corroding. CLARs determined for pre-FeCO3 filmed carbon steel show that the kinetics of FeCO3 formation reduce significantly once the film establishes a protective barrier at lower values of bulk supersaturation. The results highlight the contrast between surface layer accumulation kinetics in the early stages of growth and those encountered in the long-term after the development of a protective film.
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Cracking mechanism in API 5L X65 steel in a CO2-saturated envIronment
Engineering Failure Analysis, 2019Co-Authors: Samara Cruz Da Silva, Richard Barker, Anne Neville, Eduardo Alencar De Souza, Frederick Pessu, Yong Hua, José Antônio Da Cunha Ponciano GomesAbstract:Abstract Hydrogen charging in low alloy steels poses a significant problem in the oil and gas industry. Detrimental hydrogen effects are not commonly expected in CO2 aqueous envIronments. However, the acid nature of these envIronments and the high corrosion rates expected justify the assessment of cracking susceptibility of carbon steel in a CO2-saturated envIronment as presented in this work. The focus of this investigation is to understand how different surface films/corrosion products influence the hydrogen permeation and cracking mechanism of an API 5L X65 carbon steel in a saturated CO2 envIronment. The experiments were carried out to assess hydrogen permeation at open circuit potential on steel samples which were either wet-ground, or pre-filmed with Iron carbide (Fe3C) rich or Iron Carbonate (FeCO3) layers. Tafel measurements were also performed to determine the effect of the surface composition on the cathodic reactions. Slow strain rate tests (SSRT) were conducted in order to evaluate the effects of hydrogen on the cracking mechanisms of the steel in this sweet envIronment. Results indicated that at open circuit conditions, Fe3C was able to increase the steady state hydrogen permeation current due to accentuation of the cathodic hydrogen-evolution reaction. Although FeCO3 suppressed the cathodic reaction at the steel surface, the development of the protective and densely packed crystalline layer increased hydrogen uptake marginally from that of the ground steel reduced. SSRT indicated a very moderate loss of ductility in wet-ground and FeCO3 steel surface conditions. However, a more significant reduction in area was observed in the tests carried out on Fe3C rich samples. These results imply that a corroded API 5L X65 steel surface in a CO2 rich envIronment can enhance the hydrogen embrittlement (HE) susceptibility and as such, hydrogen permeation susceptibility needs to be considered in material selection.
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a review of Iron Carbonate feco3 formation in the oil and gas industry
Corrosion Science, 2018Co-Authors: Richard Barker, D Burkle, Thibaut V J Charpentier, H M Thompson, Anne NevilleAbstract:Abstract This paper reviews the information in the literature relating to FeCO3 formation in the context of oil and gas production. Numerous factors which influence the kinetics, physical properties and protective nature of FeCO3 are considered in addition to a review of semi-empirical models developed to predict precipitation/corrosion layer accumulation rate. The limitations of current models are discussed and the challenges of conducting deposition studies onto steel surfaces in a controlled envIronment using laboratory based techniques are also reviewed. Finally, more recently employed experimental techniques are considered in their potential to provide a further understanding of FeCO3 and mixed Carbonate kinetics.
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the early stages of feco3 scale formation kinetics in co2 corrosion
Materials Chemistry and Physics, 2018Co-Authors: R A De Motte, Richard Barker, D Burkle, S M Vargas, Anne NevilleAbstract:Abstract In a carbon dioxide (CO2) corrosive envIronment, when the product of the local concentrations of Iron (Fe2+) and Carbonate (CO32−) ions exceed the solubility limit, the precipitation of Iron Carbonate (FeCO3) on the internal walls of carbon steel pipelines can significantly reduce the corrosion rate. In the following work, static glass cell corrosion experiments were conducted to understand the precipitation behavior in the early stages of FeCO3 development and the factors favorable to protective film formation. The corrosion and precipitation rates were followed using a combination of mass gain, mass loss, electrochemistry and surface analysis techniques. At the conditions studied, the protectiveness and the rate of film formation was observed to vary significantly. The results indicated that the early stages of FeCO3 precipitation consists of a complex simultaneous nucleation and growth process. FeCO3 precipitation is shown to be dependent on surface species concentrations which can be significantly different to that of the bulk solution. Additionally, the role of crystal surface coverage and the blocking of actively corroding sites on the steel surface is examined and is shown to play a critical role in reducing precipitation kinetics at low levels of bulk super-saturation.
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evaluation of high shear inhibitor performance in co2 containing flow induced corrosion and erosion corrosion envIronments in the presence and absence of Iron Carbonate films
Wear, 2018Co-Authors: E V Senatore, Richard Barker, Yong Hua, Wassim Taleb, Joshua Owen, J Ponciano A C Gomes, Anne NevilleAbstract:Abstract Carbon steel pipeline degradation occurs as a result of erosion-corrosion during oil and gas production. Sand particles contribute to this effect when they are present in conjunction with a high flow velocity. In carbon dioxide (CO2) envIronments, and under certain conditions, the corrosion rate of the steel can be reduced by the formation of a protective Iron Carbonate (FeCO3) layer. This work assesses the ability of FeCO3 to protect the underlying steel in flow-induced corrosion and erosion-corrosion envIronments. Autoclave tests are performed at 60 °C and 100 bar in a 1 wt%NaCl CO2-saturated solution for a duration of 48 h to develop 60 µm thick FeCO3 films. The film-covered samples were then transferred into a submerged impinging jet (SIJ) apparatus to assess their ability to resist both flow-induced corrosion and erosion-corrosion envIronments at 25 °C and a flow velocity of 15 m/s (both with and without 1000 mg/L sand). Tests were also conducted in the presence of a commercially available corrosion inhibitor to evaluate the interaction. Results indicate that the FeCO3 layer is able to considerably suppress corrosion of the carbon steel substrate. Experiments in the presence of both the FeCO3 film and corrosion inhibitor demonstrated that there is a notable synergistic effect between these two components in providing resistance to erosion-corrosion.
Richard Barker - One of the best experts on this subject based on the ideXlab platform.
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Iron Carbonate formation kinetics onto corroding and pre filmed carbon steel surfaces in carbon dioxide corrosion envIronments
Applied Surface Science, 2019Co-Authors: Richard Barker, Al I Shaaili, R A De Motte, D Burkle, Thibaut V J Charpentier, S M Vargas, Anne NevilleAbstract:Abstract This work investigates the Corrosion Layer Accumulation Rate (CLAR) of Iron Carbonate (FeCO3) onto X65 carbon steel in carbon dioxide containing envIronments using the direct method of corrosion layer mass gain measurement. Glass cell experiments were performed at 80 °C and pH 6.3 or 6.8 over a range of bulk FeCO3 saturation ratios using both actively corroding carbon steel and steel pre-filmed with FeCO3. The CLARs obtained from experiments using actively corroding samples displayed strong agreement with the most recently developed precipitation model by Sun and Nesic at high supersaturation for pH 6.3 and 6.8, but a disparity at low supersaturation for the solution at pH 6.8. The observed discrepancy was attributed to the significant difference in surface saturation ratio between the two conditions when the steel is actively corroding. CLARs determined for pre-FeCO3 filmed carbon steel show that the kinetics of FeCO3 formation reduce significantly once the film establishes a protective barrier at lower values of bulk supersaturation. The results highlight the contrast between surface layer accumulation kinetics in the early stages of growth and those encountered in the long-term after the development of a protective film.
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Cracking mechanism in API 5L X65 steel in a CO2-saturated envIronment
Engineering Failure Analysis, 2019Co-Authors: Samara Cruz Da Silva, Richard Barker, Anne Neville, Eduardo Alencar De Souza, Frederick Pessu, Yong Hua, José Antônio Da Cunha Ponciano GomesAbstract:Abstract Hydrogen charging in low alloy steels poses a significant problem in the oil and gas industry. Detrimental hydrogen effects are not commonly expected in CO2 aqueous envIronments. However, the acid nature of these envIronments and the high corrosion rates expected justify the assessment of cracking susceptibility of carbon steel in a CO2-saturated envIronment as presented in this work. The focus of this investigation is to understand how different surface films/corrosion products influence the hydrogen permeation and cracking mechanism of an API 5L X65 carbon steel in a saturated CO2 envIronment. The experiments were carried out to assess hydrogen permeation at open circuit potential on steel samples which were either wet-ground, or pre-filmed with Iron carbide (Fe3C) rich or Iron Carbonate (FeCO3) layers. Tafel measurements were also performed to determine the effect of the surface composition on the cathodic reactions. Slow strain rate tests (SSRT) were conducted in order to evaluate the effects of hydrogen on the cracking mechanisms of the steel in this sweet envIronment. Results indicated that at open circuit conditions, Fe3C was able to increase the steady state hydrogen permeation current due to accentuation of the cathodic hydrogen-evolution reaction. Although FeCO3 suppressed the cathodic reaction at the steel surface, the development of the protective and densely packed crystalline layer increased hydrogen uptake marginally from that of the ground steel reduced. SSRT indicated a very moderate loss of ductility in wet-ground and FeCO3 steel surface conditions. However, a more significant reduction in area was observed in the tests carried out on Fe3C rich samples. These results imply that a corroded API 5L X65 steel surface in a CO2 rich envIronment can enhance the hydrogen embrittlement (HE) susceptibility and as such, hydrogen permeation susceptibility needs to be considered in material selection.
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a review of Iron Carbonate feco3 formation in the oil and gas industry
Corrosion Science, 2018Co-Authors: Richard Barker, D Burkle, Thibaut V J Charpentier, H M Thompson, Anne NevilleAbstract:Abstract This paper reviews the information in the literature relating to FeCO3 formation in the context of oil and gas production. Numerous factors which influence the kinetics, physical properties and protective nature of FeCO3 are considered in addition to a review of semi-empirical models developed to predict precipitation/corrosion layer accumulation rate. The limitations of current models are discussed and the challenges of conducting deposition studies onto steel surfaces in a controlled envIronment using laboratory based techniques are also reviewed. Finally, more recently employed experimental techniques are considered in their potential to provide a further understanding of FeCO3 and mixed Carbonate kinetics.
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the early stages of feco3 scale formation kinetics in co2 corrosion
Materials Chemistry and Physics, 2018Co-Authors: R A De Motte, Richard Barker, D Burkle, S M Vargas, Anne NevilleAbstract:Abstract In a carbon dioxide (CO2) corrosive envIronment, when the product of the local concentrations of Iron (Fe2+) and Carbonate (CO32−) ions exceed the solubility limit, the precipitation of Iron Carbonate (FeCO3) on the internal walls of carbon steel pipelines can significantly reduce the corrosion rate. In the following work, static glass cell corrosion experiments were conducted to understand the precipitation behavior in the early stages of FeCO3 development and the factors favorable to protective film formation. The corrosion and precipitation rates were followed using a combination of mass gain, mass loss, electrochemistry and surface analysis techniques. At the conditions studied, the protectiveness and the rate of film formation was observed to vary significantly. The results indicated that the early stages of FeCO3 precipitation consists of a complex simultaneous nucleation and growth process. FeCO3 precipitation is shown to be dependent on surface species concentrations which can be significantly different to that of the bulk solution. Additionally, the role of crystal surface coverage and the blocking of actively corroding sites on the steel surface is examined and is shown to play a critical role in reducing precipitation kinetics at low levels of bulk super-saturation.
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evaluation of high shear inhibitor performance in co2 containing flow induced corrosion and erosion corrosion envIronments in the presence and absence of Iron Carbonate films
Wear, 2018Co-Authors: E V Senatore, Richard Barker, Yong Hua, Wassim Taleb, Joshua Owen, J Ponciano A C Gomes, Anne NevilleAbstract:Abstract Carbon steel pipeline degradation occurs as a result of erosion-corrosion during oil and gas production. Sand particles contribute to this effect when they are present in conjunction with a high flow velocity. In carbon dioxide (CO2) envIronments, and under certain conditions, the corrosion rate of the steel can be reduced by the formation of a protective Iron Carbonate (FeCO3) layer. This work assesses the ability of FeCO3 to protect the underlying steel in flow-induced corrosion and erosion-corrosion envIronments. Autoclave tests are performed at 60 °C and 100 bar in a 1 wt%NaCl CO2-saturated solution for a duration of 48 h to develop 60 µm thick FeCO3 films. The film-covered samples were then transferred into a submerged impinging jet (SIJ) apparatus to assess their ability to resist both flow-induced corrosion and erosion-corrosion envIronments at 25 °C and a flow velocity of 15 m/s (both with and without 1000 mg/L sand). Tests were also conducted in the presence of a commercially available corrosion inhibitor to evaluate the interaction. Results indicate that the FeCO3 layer is able to considerably suppress corrosion of the carbon steel substrate. Experiments in the presence of both the FeCO3 film and corrosion inhibitor demonstrated that there is a notable synergistic effect between these two components in providing resistance to erosion-corrosion.
S R Allahkaram - One of the best experts on this subject based on the ideXlab platform.
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the effect of acetic acid on the co2 corrosion of grade x70 steel
Materials & Design, 2010Co-Authors: Mehdi Honarvar Nazari, S R AllahkaramAbstract:The effect of acetic acid (HAc) on the CO2 corrosion of grade X70 steel was investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), polarization tests and electrochemical impedance spectroscopy (EIS). In the absence of acetic acid, a fairly dense layer of Iron Carbonate (FeCO3/siderite) was formed. At 500 ppm HAc, FeCO3 layer became more porous. In addition, anodic/cathodic polarization curves were activated with the more pronounced effect on the cathodic side. By adding 1000 ppm HAc, similar polarization behavior was obtained and FeCO3 layer became yet more porous than previous conditions. At 2000 ppm HAc, FeCO3 layer disappeared completely, while polarization behavior changed and the limiting diffusive current density was observed in the cathodic side. There were two major increases in the corrosion rate at 500 and 2000 ppm HAc. The EIS results reflected similar behavior for the specimens exposed to the solutions with 0–1000 ppm HAc. Under these conditions, a charge transfer controlled behavior due to the FeCO3 layer was observed which was accelerated by increasing HAc concentration. At 2000 ppm HAc, the corrosion behavior changed considerably and the formation/adsorption of corrosion product followed by the dissolution process was observed.
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the effects of temperature and ph on the characteristics of corrosion product in co2 corrosion of grade x70 steel
Materials & Design, 2010Co-Authors: Honarvar M Nazari, S R Allahkaram, M B KermaniAbstract:Abstract The effects of temperature and the in situ pH on the composition and morphology of corrosion product layers in the CO 2 corrosion of X70 steel were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses, respectively. The experiments were carried out in a range conditions including temperature 55–85 °C and pH 5.5–6.5 over a period of 72 h. At 55 °C, no corrosion product was formed on the steel surface at any pH conditions. By increasing the temperature to 65 °C, Iron Carbonate (FeCO 3 ) phase was formed at all pH conditions with an apparently non-compact morphology. Raising the pH increased the compactness of the layer. At 75 and 85 °C, a compact layer was formed at all pH conditions, while the most compactness was seen at pH 6.5 for both of these temperatures. It was also observed that the thickness of FeCO 3 layer increased with increasing temperature. Therefore, it could be concluded that the optimum conditions for producing a compact and thick layer of FeCO 3 was obtained at temperature of 85 °C and pH 6.5.
Ahmed Barifcani - One of the best experts on this subject based on the ideXlab platform.
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Effect of Dissolved Oxygen, Sodium Bisulfite, and Oxygen Scavengers on Methane Hydrate Inhibition
Journal of Chemical & Engineering Data, 2018Co-Authors: Khalid Alef, Stefan Iglauer, Ahmed BarifcaniAbstract:Numerous chemical additives are added to monoethylene glycol (MEG) injection streams to maintain and protect assets as well as to ensure steady production of hydrocarbons. Oxygen scavengers are injected for the purpose of lowering dissolved oxygen to levels that do not pose the risk of corrosion. In this study, the effect of dissolved oxygen and some oxygen scavengers on gas hydrate inhibition was investigated. Results reveal that high levels of dissolved oxygen may promote the formation of hydrates due to the reaction of dissolved oxygen with impurity components such as Iron Carbonate that may exist in the MEG solution, thus decreasing overall MEG quality. Sodium bisulfite had negligible effect on hydrate inhibition at low concentrations but showed greater inhibition performance at higher concentrations due to the electrostatic attraction between ions and water molecules. A proprietary oxygen scavenger showed hydrate promotion effect, which suggests that proprietary chemical additives should undergo exte...
