Molecular dynamics simulation of the microscopic mechanisms of the dissolution, diffusion and aggregation processes for waxy crystals in crude oil mixtures

Gan, Yifan; Cheng, Qinglin; Wang, Zhihua; Yang, Jian; Sun, Wei; Liu, Yang

doi:10.1016/j.petrol.2019.04.059

Cited by 36 publications

(18 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The non-bond energy and the potential energy of aluminum sol models (25 wt%) varied with oligomers component proportion, which is listed in Table 1 . Negative values indicate that non-bond energy dominates the attraction between solvent molecules and oligomers [ 33 , 34 ]. The results demonstrated that the non-bond energy of aluminum sol models decreased with the decrease in B proportion.…”

Section: Resultsmentioning

confidence: 99%

Experimental and Molecular Dynamics Simulation Study on Sol–Gel Conversion Process of Aluminum Carboxylate System

Luo

Yao

et al. 2022

Materials

View full text Add to dashboard Cite

Due to the lack of relevant in situ characterization techniques, the investigation of aluminum sol–gel progress is lacking. In this study, combined with molecular dynamics simulation and conventional experimental methods, the microstructures, rheological properties, and gelation process of the carboxylic aluminum sol system were studied. The experimental results showed that, with the increase in solid content, the microstructure of the colloid developed from a loose and porous framework to a homogeneous and compact structure. The viscosity of aluminum sol decreased significantly with the increase in temperature, and a temperature above 318 k was more conducive to improving the fluidity. The simulation results show that the increase in free volume and the connectivity of pores in colloidal framework structure were the key factors to improve fluidity. In addition, free water molecules had a higher migration rate, which could assist the rotation and rearrangement of macromolecular chains and also played an essential role in improving fluidity. The Molecular dynamics simulation (MD) results were consistent with experimental results and broaden the scope of experimental research, providing necessary theoretical guidance for enhancing the spinning properties of aluminum sol.

show abstract

Section: Resultsmentioning

confidence: 99%

Experimental and Molecular Dynamics Simulation Study on Sol–Gel Conversion Process of Aluminum Carboxylate System

Luo

Yao

et al. 2022

Materials

View full text Add to dashboard Cite

show abstract

“…At present, this technique is widely used to model complex systems, as it provides a highly accurate description of particle motion according to Newton's laws of dynamics and allows the phase trajectories of a given molecular system to be obtained by numerical simulation, thus enabling the acquisition of thermodynamic data and system structural characteristics [36]. To understand the micromechanism and thermodynamics of phase transformations and the precipitation of waxy crystals in crude oil mixtures, we probed the phase transformation and gelling behavior of waxy molecules in the oil-asphaltene-water multiphase system by MD simulation [37], with the employed system model and related details shown in Fig. 1.…”

Section: Molecular Dynamics Simulationmentioning

confidence: 99%

“…4 MSDs of oil molecules along the Z-direction in the presence of different surfactants [47] Taking the waxy crude oil with 10% water volume fraction as an example, as shown in Fig. 5, in order to analyze the role of different operating parameters on the diffusion behavior of wax molecules at the oil-water interface, the relationship between diffusion coefficient (D) and system pressure under different temperature conditions was established in our previous study [37]. The diffusion coefficient values indicate that the diffusion coefficient of waxy molecules increase continuously with the increase in relaxation pressure.…”

Section: A U T H O R Accepted Manuscript Author Accepted Manuscriptmentioning

confidence: 99%

Molecular Dynamics-Based Simulation on Chemical Flooding Produced Emulsion Formation and Stabilization: A Critical Review

Wang

Liu

et al. 2020

Arab J Sci Eng

Self Cite

View full text Add to dashboard Cite

Oil-water emulsions are commonly encountered at various stages of petroleum production. For example, the alkaline-surfactant-polymer (ASP) flooding is extensively used to promote emulsion formation, and thus, enhance oil recovery (EOR). However, the chemicals (e.g. polymers and surfactants) involved in this process can also stabilize the produced emulsions to adversely affect the subsequent processes of oil field surface systems. Therefore, a deep understanding of oil-water emulsions formation and stabilization is required to guarantee and promote oil field production. This work summarizes the current knowledge on (i) the formation of oil-water emulsions, (ii) the influence of crude oil components (e.g. asphaltenes and resins), and (iii) the above-mentioned water phase components on emulsions stability on a macroscopic scale. Moreover, considering the importance of molecular dynamics (MD) simulation for revealing interphase interactions and its advantages of microstructure characterization, we also probe the mechanism of such simulations, discuss the obtained results, and reveal progress in the elucidation of the mechanism of oil-water interface stabilization. MD simulation is shown to shed light on oil-water emulsification and demulsification processes and is concluded to be well suited for exploring molecular adsorption, droplet coalescence, and droplet separation on a micro scale. However, future researchers should aim to circumvent the limitations of model simplification and single-factor simulation, integrate the characteristics of internal and external phase components, and consider external factors like temperature and pressure to comprehensively analyze crude oil emulsification and demulsification behavior. Furthermore, the potential role of bubbles on produced emulsion structure should be considered in future simulations.

show abstract

“…Compared with traditional experimental methods, molecular simulation technology has significant advantages. For example, it can reveal the nature of a molecule's interaction from a microperspective, and it can also predict the properties of different chemical compounds without spending a lot of time and cost on experiments [14][15][16][17].…”

Section: Introductionmentioning

confidence: 99%

Investigating the Compatibility of Various Components in Marine Low-Sulfur Fuel Oil by Molecular Dynamics Simulations

Zhou

Wei

Xue

et al. 2021

Journal of Chemistry

View full text Add to dashboard Cite

Asphaltene aggregation and precipitation are one of the major issues for marine low-sulfur fuel oil used on board. Many research studies have been carried out to investigate the aggregation behavior of asphaltene under different conditions, but the mechanism of asphaltene aggregation in low-sulfur fuel oil at the molecular level is still unclear. In this work, molecular dynamics (MD) simulations were performed to calculate the solubility parameters, intermolecular interaction energies, and radial distribution function (RDF) curves of each component in marine low-sulfur fuel oil to examine their mutual compatibility. Simulation results indicate that the solubility parameter of resin gains the highest value and it is close to asphaltene. The solubility parameters of aromatic, hexadecane, and saturate decrease successively. The interaction energy between resin and asphaltene molecules is higher than that between the same kind of molecules, which means that resin can inhibit the aggregation of asphaltene molecules. Typically, a light distillate component (hexadecane) is added to heavy fuel oil to yield low-sulfur oil, and our calculations reveal that this has a negative effect on asphaltene aggregation. Specifically, asphaltene is more likely to self-aggregate, as shown by the increase in peak height in the radial distribution function of the asphaltene-asphaltene pair. The findings of this study will provide theoretical support for the production of marine low-sulfur fuel.

show abstract

Molecular dynamics simulation of the microscopic mechanisms of the dissolution, diffusion and aggregation processes for waxy crystals in crude oil mixtures

Cited by 36 publications

References 41 publications

Experimental and Molecular Dynamics Simulation Study on Sol–Gel Conversion Process of Aluminum Carboxylate System

Experimental and Molecular Dynamics Simulation Study on Sol–Gel Conversion Process of Aluminum Carboxylate System

Molecular Dynamics-Based Simulation on Chemical Flooding Produced Emulsion Formation and Stabilization: A Critical Review

Investigating the Compatibility of Various Components in Marine Low-Sulfur Fuel Oil by Molecular Dynamics Simulations

Contact Info

Product

Resources

About