Relation and Correlation between NMR Relaxation Times, Diffusion Coefficients, and Viscosity of Heavy Crude Oils

Korb, Jean-Pierre; Vorapalawut, Nopparat; Nicot, Benjamin; Bryant, Robert G.

doi:10.1021/acs.jpcc.5b07510

Cited by 66 publications

(98 citation statements)

References 26 publications

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“…18). Consideration of all these experiments suggests a transition for the translational diffusion coefficient from the usual Stokes-Einstein relation D / 1/g which is conserved at low asphaltene concentrations below a threshold viscosity g c to a wetting behaviour where the diffusion coefficient does not vary with the viscosity close to the asphaltene aggregates at higher asphaltene concentration above g c [114] (Fig. 15).…”

Section: Comparison With the Observed Viscosity Dependencies Of T 1 Amentioning

confidence: 96%

“…For heavy crude oils, the presence of asphaltenes creates some anomalous features in the observed two-dimensional correlation plots displayed in Figs. 16 and 17, respectively [114] that will be discussed in Sections 8.1.3 and 8.1.4. Asphaltenes have been shown to associate at higher concentrations, making complex particles that in turn may aggregate to make macro-aggregates [109,115].…”

Section: Relations Between Nmr Relaxation Times Diffusion Coefficienmentioning

confidence: 99%

“…One can thus assume a similar form for a viscosity gradient on a limited range of distance x from the surface of the macro-aggregates that will influence the translational dynamics of hydrocarbons. For these reasons, the following a priori exponential form has been introduced [114]:…”

Section: Relations Between Nmr Relaxation Times Diffusion Coefficienmentioning

confidence: 99%

“…15). Relaxation equations are shown [114] for the longitudinal and transverse nuclear relaxation rates constants 1/T 1 and 1/T 2 of the observed protons of saturated hydrocarbon chains diffusing among the clusters of asphaltenes containing the paramagnetic species VO 2+ (Fig. 18).…”

Section: Comparison With the Observed Viscosity Dependencies Of T 1 Amentioning

confidence: 99%

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Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

Korb

2018

Progress in Nuclear Magnetic Resonance Spectroscopy

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153

161

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The nuclear magnetic relaxation dispersion (NMRD) technique consists of measurement of the magnetic-field dependence of the longitudinal nuclear-spin-lattice relaxation rate 1/T. Usually, the acquisition of the NMRD profiles is made using a fast field cycling (FFC) NMR technique that varies the magnetic field and explores a very large range of Larmor frequencies (10 kHz < ω/(2π) <40 MHz). This allows extensive explorations of the fluctuations to which nuclear spin relaxation is sensitive. The FFC technique thus offers opportunities on multiple scales of both time and distance for characterizing the molecular dynamics and transport properties of complex liquids in bulk or embedded in confined environments. This review presents the principles, theories and applications of NMRD for characterizing fundamental properties such as surface correlation times, diffusion coefficients and dynamical surface affinity (NMR wettability) for various confined liquids. The basic longitudinal and transverse relaxation equations are outlined for bulk liquids. The nuclear relaxation of a liquid confined in pores is considered in detail in order to find the biphasic fast exchange relations for a liquid at proximity of a solid surface. The physical-chemistry of liquids at solid surfaces induces striking differences between NMRD profiles of aprotic and protic (water) liquids embedded in calibrated porous disordered materials. A particular emphasis of this review concerns the extension of FFC NMR relaxation to industrial applications. For instance, it is shown that the FFC technique is sufficiently rapid for following the progressive setting of cement-based materials (plasters, cement pastes, concretes). The technique also allows studies of the dynamics of hydrocarbons in proximity of asphaltene nano-aggregates and macro-aggregates in heavy crude oils as a function of the concentration of asphaltenes. It also gives new information on the wettability of petroleum fluids (brine and oil) embedded in shale oil rocks. It is useful for understanding the relations and correlations between NMR relaxation times T and T, diffusion coefficients D, and viscosity η of heavy crude oils. This is of particular importance for interpreting T, T, 2D T-T and D-T correlation spectra that could be obtained down-hole, thus giving a valuable tool for investigating in situ the molecular dynamics of petroleum fluids. Another domain of interest concerns biological applications. This is of particular importance for studying the complex dynamical spectrum of a folded polymeric structure that may span many decades in frequency or time. A direct NMRD characterization of water diffusional dynamics is presented at the protein interface. NMR experiments using a shuttle technique give results well above the frequency range accessible via the FFC technique; examples of this show protein dynamics over a range from fast and localized motions to slow and delocalized collective motions involving the whole protein. This review ends by an interpretation of the origin of the proto...

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Section: Comparison With the Observed Viscosity Dependencies Of T 1 Amentioning

confidence: 96%

Section: Relations Between Nmr Relaxation Times Diffusion Coefficienmentioning

confidence: 99%

Section: Relations Between Nmr Relaxation Times Diffusion Coefficienmentioning

confidence: 99%

Section: Comparison With the Observed Viscosity Dependencies Of T 1 Amentioning

confidence: 99%

See 2 more Smart Citations

Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

Korb

2018

Progress in Nuclear Magnetic Resonance Spectroscopy

Self Cite

153

161

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“…For instance, studying crude oils with D - NMR Hürlimann [32] observed a more general power law relationship for and D . Across the samples the exponent, , varies from 0.5 to as high as 4.9.Korb et al [33] demonstrated, that the presence of asphaltenes changes diffusion-relaxation relationship in crude oils to .…”

Section: Correlation Of Diffusivity Viscosity and Nmr Relaxationmentioning

confidence: 99%

Temperature-Dependent Oxygen Effect on NMR D-$$T_2$$ Relaxation-Diffusion Correlation of n-Alkanes

Shikhov

Arns

2016

Appl Magn Reson

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Nuclear magnetic resonance (NMR) diffusion-relaxation correlation experiments (D-) are widely used for the petrophysical characterisation of rocks saturated with petroleum fluids both in situ and for laboratory analyses. The encoding for both diffusion and relaxation offers increased fluid typing contrast by discriminating fluids based on their self-diffusion coefficients, while relaxation times provide information about the interaction of solid and fluid phases and associated confinement geometry (if NMR responses of pure fluids at particular temperature and pressure are known). Petrophysical interpretation of D- correlation maps is typically assisted by the “standard alkane line”—a relaxation-diffusion correlation valid for pure normal alkanes and their mixtures in the absence of restrictions to diffusing molecules and effects of internal gradients. This correlation assumes fluids are free from paramagnetic impurities. In situations where fluid samples cannot be maintained at air-free state the diffusion-relaxation response of fluids shift towards shorter relaxation times due to oxygen paramagnetic relaxation enhancement. Interpretation of such a response using the “standard alkane line” would be erroneous and is further complicated by the temperature-dependence of oxygen solubility for each component of the alkane mixture. We propose a diffusion-relaxation correlation suitable for interpretation of low-field NMR D- responses of normal alkanes and their mixtures saturating rocks over a broad temperature range, in equilibrium with atmospheric air. We review and where necessary revise existing viscosity-relaxation correlations. Findings are applied to diffusion-relaxation dependencies taking into account the temperature dependence of oxygen solubility and solvent vapour pressure. The effect is demonstrated on a partially saturated carbonate rock.

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NMR Self‐Diffusion and Transverse Relaxation Time in Bitumen: The Effect of Aging

Porto,

Angelico,

Calandra

et al. 2023

ChemPhysChem

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In this investigation the dynamics of two types of bitumens with different penetration grade were tested by using dynamic shear rheometry (DSR) and Nuclear Magnetic Resonance (NMR) at unaged conditions, and upon both short‐ and long‐term artificial aging. The gel‐sol transition temperature was found to increase with increasing the time of aging treatment. Arrhenius parameters of the viscosity were found, unexpectedly, to be correlated with those of simple liquids, suggesting that the two kinds of systems, although chemically and physically quite different, share the same basic process at the molecular level. The molecular dynamics has been then investigated by NMR Pulsed Field Gradient Stimulated‐Echo (PFGSE) and relaxometry (Carr‐Purcell‐Meiboom‐Gill, CPMG, spin‐echo pulse sequence) to capture the effect of aging upon dynamics variables such as self‐diffusion coefficients D and transverse relaxation times T2. The translational diffusion at T > of the light molecular components of both types of bitumens was characterized by broad distributions of D which were found independent of the experimental time scale up to 0.2 s. Similarly, T2 data could be described as a continuous unimodal distributions of relaxation times determined both at T < and T > .

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Relation and Correlation between NMR Relaxation Times, Diffusion Coefficients, and Viscosity of Heavy Crude Oils

Cited by 66 publications

References 26 publications

Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

Temperature-Dependent Oxygen Effect on NMR D-$$T_2$$ Relaxation-Diffusion Correlation of n-Alkanes

NMR Self‐Diffusion and Transverse Relaxation Time in Bitumen: The Effect of Aging

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