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Yang Y, Che Ruslan MFA, Narayanan Nair AK, Qiao R, Sun S. Interfacial properties of the hexane + carbon dioxide + water system in the presence of hydrophilic silica. J Chem Phys 2022; 157:234704. [PMID: 36550045 DOI: 10.1063/5.0130986] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Molecular dynamics simulations were conducted to study the interfacial behavior of the CO2 + H2O and hexane + CO2 + H2O systems in the presence of hydrophilic silica at geological conditions. Simulation results for the CO2 + H2O and hexane + CO2 + H2O systems are in reasonable agreement with the theoretical predictions based on the density functional theory. In general, the interfacial tension (IFT) of the CO2 + H2O system exponentially (linearly) decreased with increasing pressure (temperature). The IFTs of the hexane + CO2 + H2O (two-phase) system decreased with the increasing mole fraction of CO2 in the hexane/CO2-rich phase xCO2 . Here, the negative surface excesses of hexane lead to a general increase in the IFTs with increasing pressure. The effect of pressure on these IFTs decreased with increasing xCO2 due to the positive surface excesses of carbon dioxide. The simulated water contact angles of the CO2 + H2O + silica system fall in the range from 43.8° to 76.0°, which is in reasonable agreement with the experimental results. These contact angles increased with pressure and decreased with temperature. Here, the adhesion tensions are influenced by the variations in fluid-fluid IFT and contact angle. The simulated water contact angles of the hexane + H2O + silica system fall in the range from 58.0° to 77.0° and are not much affected by the addition of CO2. These contact angles increased with pressure, and the pressure effect was less pronounced at lower temperatures. Here, the adhesion tensions are mostly influenced by variations in the fluid-fluid IFTs. In all studied cases, CO2 molecules could penetrate into the interfacial region between the water droplet and the silica surface.
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Affiliation(s)
- Yafan Yang
- State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
| | - Mohd Fuad Anwari Che Ruslan
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Rui Qiao
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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Yang Y, Anwari Che Ruslan MF, Zhu W, Zhao G, Sun S. Interfacial Behaviors of the H2O+CO2+CH4+C10H22 System in Three Phase Equilibrium: A Combined Molecular Dynamics Simulation and Density Gradient Theory Investigation. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.121031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Narayanan Nair AK, Che Ruslan MFA, Cui R, Sun S. An Overview of the Oil+Brine Two-Phase System in the Presence of Carbon Dioxide, Methane, and Their Mixture. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c03089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Affiliation(s)
- Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Mohd Fuad Anwari Che Ruslan
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Ronghao Cui
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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Narayanan Nair AK, Anwari Che Ruslan MF, Ramirez Hincapie ML, Sun S. Bulk and Interfacial Properties of Brine or Alkane in the Presence of Carbon Dioxide, Methane, and Their Mixture. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c00249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Mohd Fuad Anwari Che Ruslan
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Marcia Luna Ramirez Hincapie
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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Yang Y, Narayanan Nair AK, Che Ruslan MFA, Sun S. Interfacial properties of the aromatic hydrocarbon + water system in the presence of hydrophilic silica. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118272] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Choudhary N, Anwari Che Ruslan MF, Narayanan Nair AK, Qiao R, Sun S. Bulk and Interfacial Properties of the Decane + Brine System in the Presence of Carbon Dioxide, Methane, and Their Mixture. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c01607] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nilesh Choudhary
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Mohd Fuad Anwari Che Ruslan
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Rui Qiao
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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Ruslan MFAC, Youn DJ, Aarons R, Sun Y, Sun S. Numerical Analysis of a Continuous Vulcanization Line to Enhance CH 4 Reduction in XLPE-Insulated Cables. Materials (Basel) 2021; 14:ma14041018. [PMID: 33670006 PMCID: PMC7926779 DOI: 10.3390/ma14041018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 02/04/2021] [Accepted: 02/10/2021] [Indexed: 11/25/2022]
Abstract
Herein, we apply a computational diffusion model based on Fick’s law to study the manner in which a cable production line and its operating conditions can be enhanced to effectively reduce the CH4 concentration in cables insulated with cross-linked polyethylene (XLPE). Thus, we quantitatively analyze the effect of the conductor temperature, curing tube temperature distribution, transition zone length, and online relaxation on CH4 generation and transport during the production of 132 kV cables with an insulation thickness of 16.3 mm. Results show that the conductor temperature, which is initially controlled by a preheater, and the curing tube temperature distribution considerably affect the CH4 concentration in the cable because of their direct impact on the insulation temperature. The simulation results show 2.7% less CH4 remaining in the cable when the preheater is set at 160 °C compared with that when no preheater is used. To study the curing tube temperature distribution, we consider three distribution patterns across the curing tube: constant temperature and linear incremental and decremental temperature. The amount of CH4 remaining in the cable when the temperature was linearly increased from 300 to 400 °C was 1.6% and 3.7% lower than in the cases with a constant temperature at 350 °C and a linear temperature decrease from 400 to 300 °C, respectively. In addition, simulations demonstrate that the amount of CH4 removal from the cable can be increased up to 9.7% by applying an elongated and insulated transition zone, which extends the residence time for CH4 removal and decelerates the decrease in cable temperature. Finally, simulations show that the addition of the online relaxation section can reduce the CH4 concentration in the cable because the high cable temperature in this section facilitates CH4 removal up to 2.2%, and this effect becomes greater at low production speeds.
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Affiliation(s)
- Mohd Fuad Anwari Che Ruslan
- Computational Transport Phenomena Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia;
| | - Dong Joon Youn
- Computational Transport Phenomena Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia;
- Correspondence: (D.J.Y.); (S.S.); Tel.: +966-12-808-0642 (D.J.Y.); +966-12-808-0242 (S.S.)
| | | | - Yabin Sun
- Dow Chemical (China) Investment Co., Ltd., Shanghai 201203, China;
| | - Shuyu Sun
- Computational Transport Phenomena Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia;
- Correspondence: (D.J.Y.); (S.S.); Tel.: +966-12-808-0642 (D.J.Y.); +966-12-808-0242 (S.S.)
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Choudhary N, Che Ruslan MFA, Narayanan Nair AK, Sun S. Bulk and Interfacial Properties of Alkanes in the Presence of Carbon Dioxide, Methane, and Their Mixture. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c04843] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nilesh Choudhary
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Mohd Fuad Anwari Che Ruslan
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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Yang Y, Narayanan Nair AK, Anwari Che Ruslan MF, Sun S. Bulk and Interfacial Properties of the Decane + Water System in the Presence of Methane, Carbon Dioxide, and Their Mixture. J Phys Chem B 2020; 124:9556-9569. [PMID: 33059452 DOI: 10.1021/acs.jpcb.0c05759] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular dynamics simulations are carried out to study the two-phase behavior of the n-decane + water system in the presence of methane, carbon dioxide, and their mixture under reservoir conditions. The simulation studies were complemented by theoretical modeling using the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state (EoS) and density gradient theory. Our results show that the presence of methane and carbon dioxide decreases the interfacial tension (IFT) of the decane + water system. In general, the IFT increases with increasing pressure and decreasing temperature for the methane + decane + water and carbon dioxide + decane + water systems, similar to what has been found for the corresponding decane + water system. The most important finding of this study is that the presence of carbon dioxide decreases the IFT of the methane + decane + water system. The atomic density profiles provide evidence of the local accumulation of methane and carbon dioxide at the interface, in most of the studied systems. The results of this study show the preferential dissolution in the water-rich phase and enrichment at the interface for carbon dioxide in the methane + carbon dioxide + decane + water system. This indicates the preferential interaction of water with carbon dioxide relative to methane and decane. Notably, there is an enrichment of the interface by decane at high mole fractions of methane in the methane/decane-rich or methane/carbon dioxide/decane-rich phase. Overall, the solubility of methane and carbon dioxide in the water-rich phase increases with increasing pressure and temperature. Additionally, we find that the overall performance of the PC-SAFT EoS and the cubic-plus-association EoS is similar with respect to the calculation of bulk and interfacial properties of these systems.
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Affiliation(s)
- Yafan Yang
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Mohd Fuad Anwari Che Ruslan
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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Ruslan MFAC, Youn DJ, Aarons R, Sun Y, Sun S. Numerical Study of CH 4 Generation and Transport in XLPE-Insulated Cables in Continuous Vulcanization. Materials (Basel) 2020; 13:ma13132978. [PMID: 32635300 PMCID: PMC7372417 DOI: 10.3390/ma13132978] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/27/2020] [Accepted: 06/30/2020] [Indexed: 11/16/2022]
Abstract
In this work, we apply a computational diffusion model based on Fick's laws to study the generation and transport of methane (CH 4 ) during the production of a cross-linked polyethylene (XLPE) insulated cable. The model takes into account the heating process in a curing tube where most of the cross-linking reaction occurs and the subsequent two-stage cooling process, with water and air as the cooling media. For the calculation of CH 4 generation, the model considers the effect of temperature on the cross-linking reaction selectivity. The cross-linking reaction selectivity is a measure of the preference of cumyloxy to proceed either with a hydrogen abstraction reaction, which produces cumyl alcohol, or with a β -scission reaction, which produces acetophenone and CH 4 . The simulation results show that, during cable production, a significant amount of CH 4 is generated in the XLPE layer, which diffuses out of the cable and into the conductor part of the cable. Therefore, the diffusion pattern becomes a non-uniform radial distribution of CH 4 at the cable take-up point, which corresponds well with existing experimental data. Using the model, we perform a series of parametric studies to determine the effect of the cable production conditions, such as the curing temperature, line speed, and cooling water flow rate, on CH 4 generation and transport during cable production. The results show that the curing temperature has the largest impact on the amount of CH 4 generated and its distribution within the cable. We found that under similar curing and cooling conditions, varying the line speed induces a notable effect on the CH 4 transport within the cable, while the cooling water flow rate had no significant impact.
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Affiliation(s)
- Mohd Fuad Anwari Che Ruslan
- Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia;
| | - Dong Joon Youn
- Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia;
- Correspondence: (D.J.Y.); (S.S.); Tel.: +966-12-808-0642 (D.J.Y.); +966-12-808-0242 (S.S.)
| | | | - Yabin Sun
- Dow Chemical (China) Investment Co., Ltd., Shanghai 200203, China;
| | - Shuyu Sun
- Computational Transport Phenomena Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia;
- Correspondence: (D.J.Y.); (S.S.); Tel.: +966-12-808-0642 (D.J.Y.); +966-12-808-0242 (S.S.)
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Yang Y, Che Ruslan MFA, Narayanan Nair AK, Sun S. Effect of Ion Valency on the Properties of the Carbon Dioxide-Methane-Brine System. J Phys Chem B 2019; 123:2719-2727. [PMID: 30843699 DOI: 10.1021/acs.jpcb.8b12033] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Molecular dynamics simulations and theoretical analysis were carried out to study the bulk and interfacial properties of carbon dioxide-methane-water and carbon dioxide-methane-brine systems under geological conditions. The density gradient theory with the bulk phase properties estimated using the cubic-plus-association (CPA) equation of state (EoS) can well describe the increase in the interfacial tension (IFT) of the CO2-water system in the presence of methane. The theoretical estimates of species mole fractions in the carbon dioxide-methane-water system are in good quantitative agreement with the experimental results. Furthermore, simulations of carbon dioxide-methane-brine system show that the IFT of the CaCl2 case is generally higher than that of the NaCl case. This is probably due to the stronger hydration of Ca2+ ions and their stronger repulsion from the interface compared to Na+. While the overall shape of the ionic profiles is not much affected by the ion type, the water profiles show a local enrichment at the interface in the system with CaCl2. In contrast to the case of NaCl, the slopes of the plots of IFT vs CaCl2 concentration are dependent on temperature. Species mole fractions in the carbon dioxide-methane-brine system predicted by combining the CPA EoS with the Debye-Hückel electrostatic term are in good agreement with simulation results.
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Affiliation(s)
- Yafan Yang
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory , King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900 , Saudi Arabia
| | - Mohd Fuad Anwari Che Ruslan
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory , King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900 , Saudi Arabia
| | - Arun Kumar Narayanan Nair
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory , King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900 , Saudi Arabia
| | - Shuyu Sun
- Physical Science and Engineering Division (PSE), Computational Transport Phenomena Laboratory , King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900 , Saudi Arabia
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