Oil & Gas Science and Technology

https://ogst.ifpenergiesnouvelles.fr/

List of Papers (Total 990)

Modeling of 1D Anomalous Diffusion in Fractured Nanoporous Media

Fractured nanoporous reservoirs include multi-scale and discontinuous fractures coupled with a complex nanoporous matrix. Such systems cannot be described by the conventional dual-porosity (or multi-porosity) idealizations due to the presence of different flow mechanisms at multiple scales. More detailed modeling approaches, such as Discrete Fracture Network (DFN) models...

Rheophysics of Lamellar Phases

We have developed several techniques to study the effect of shear on complex fluids. These techniques are based on shear cells specially adapted to scattering techniques or transport properties. A brief description of the cells will be given together with the results that can be obtained using these techniques. Exemples on lyotropic systems will be detailed. The effect of shear...

Reversible Thermoassociation of Water-Soluble Polymers

In various industrial fields, water soluble polymers are commonly used as thickening agents to control the reology of aqueous fluids. Nevertheless, their properties are weakened as the temperature increases. In order to overcome this problem, the concept of thermoassociativewater soluble polymers was developed. Such new amphilic systems can be obtained by grafting on an...

Low Temperature Rheological Behavior of Umbarka Waxy Crude and Influence of Flow Improver

The low temperature flow properties; pour point and rheological parameters; have been determined for untreated and additive treated Umbarka waxy crude. The rheological characteristics of the crude showed non-Newtonian yield pseudoplastic flow behavior and pronounced thixotropic effect. Viscometric data are fitted to Bingham, Casson and Herschel-Bulkley plastic flow models using...

Prediction of Volumetric Properties and (Multi-) Phase Behaviour of Asphaltenic Crudes

Asphaltenes flocculation is described as a thermodynamic transition inducing the formation of a new liquid phase with a high asphaltenic content; this phase being the asphaltenic deposit. The thermodynamic model selected is the Peng-Robinson Equation of State associated with the Abdoul and Péneloux group contribution mixing rules. The oil is modeled by 33 pseudocomponents. Mainly...

Structure et dynamique d'une couche de liquide au voisinage d'une surface solide de milieux nanoporeux

Cet article montre les potentialités de la relaxation nucléaire dans l'étude de la microdynamique de liquides moléculaires dans différents systèmes confinés et poreux, et en particulier aux interfaces solide-liquide. Nous avons mis en évidence une réduction et une anisotropie de la dynamique de réorientation moléculaire de liquides à la surface de pores nanomètriques dans diff...

Kelvin Notation for Stabilizing Elastic-Constant Inversion

Inverting a set of core-sample traveltime measurements for a complete set of 21 elastic constants is a difficult problem. If the 21 elastic constants are directly used as the inversion parameters, a few bad measurements or an unfortunate starting guess may result in the inversion converging to a physically impossible solution . Even given perfect data, multiple solutions may...

A Rapid and Efficient Methodology to Convert Fractured Reservoir Images Into a Dual-Porosity Model

Both characterization and dynamic simulation of naturally-fractured reservoirs have benefited from major advances in recent years. However, the reservoir engineer is still faced with the difficulty of parameterizing the dual-porosity model used to represent such reservoirs. In particular, the equivalent fracture permeabilities and the equivalent matrix block dimensions of such a...

Combustion Modeling with the G-Equation

Numerical investigations concerning the turbulent flame front propagation in Gasoline Direct Injection (GDI) engines were made by implementing a flamelet model in the CFD code Fire. The advantage of this combustion model is the decoupling of the chemistry from the turbulent flow. For this purpose the combustion chamber has to be divided into a burned and an unburned area, which...

Multi-Dimensional Modeling of Combustion and Pollutants Formation of New Technology Light Duty Diesel Engines

In the present paper some results, obtained by the use of modern numerical CFD tools, are presented. In particular, starting from the experimental characterization of a common rail DI Diesel engine, the empirical constants of the different submodels were tuned to obtain satisfactory results in some key test conditions. The main constraints of numerical models, to obtain a right...

Synthetic Or Reformulated Fuels: a Challenge for Catalysis

Despite comparative figures for wordwide crude oil and natural gas proven reserves, present time contribution of syngas chemistry to motorfuels remains marginal when the refining industry is faced to main constraints: market demand evolution, stringent specifications and environmental issues. Actually natural gas upgrading via syngas chemistry yields key products (e. g. methanol...

Structural Modification of Cobalt Catalysts: Effect of Wetting Studied by X-Ray and Infrared Techniques

The effect of wetting on the structure and localisation of cobalt species on various supports (Al2O3, SiO2, TiO2, HZSM-5 zeolite) was studied using X-ray diffraction, Fourier transform infrared spectroscopy with CO as a molecular probe, X-ray photoelectron spectroscopy and extended X-ray absorption fine structure analysis. Aqueous impregnation to incipient wetness of reduced and...

Theory and Practice of a New Class of Equipment for Separation of Particulates from Gases: the Turbulent Flow Precipitator

The main classes of separators of particulates from gases comprise inertial separators, filters, (wet) scrubbers and electrostatic precipitators, each of which technique has its proper niche and each has its advantages and its disadvantages. In the present paper a new class of equipment, the turbulent flow precipitator (TFP) for gas cleaning is described that, though at the...

A Fully Analytical Solution of the Wellbore Stability Problem under Undrained Conditions Using a Linearised Cam-Clay Model

This paper presents a linearised version of the Cam-Clay model fully integrated in the scope of the general theory of poroplasticity. The constitutive law which is developed in the scope of the effective plastic stress concept, only contains two plastic parameters (hardening modulus and slope of the critical state line). To be validated, the model is integrated over homogeneous...

A Hydro-Geomechanical View of Seal Formation and Failure in Overpressured Basins

The formation of seals, and the consequent retention of overpressure, is a common and expected event during normal basin evolution in active basins that have a significant mudrock succession. Seal failure, and the resultant limitation to fluid-pressure increase (valve action), is also an expected process. Hydro-geomechanical concepts, including poro-elasto-visco-plasticity (PEVP...

Poroelasticity and Poroplasticity At Large Strains

This paper reviews some aspects of the formulation of the constitutive behavior of a saturated porous material in isothermal evolutions in the domain of large strains. First, the results concerning the nonporous solid are recalled. Then, the poroelastic and poro-elastoplastic behaviors at large strains are successively considered. When the solid phase is elastic at large strains...

Rock Permeability and Fluid Pressure At the Ktb. Implications from Laboratory-And Drill Hole-Measurements

Rock permeability and the fluid pressure were investigated at different scales at the two drill holes of the Continental Deep Drilling Program (KTB). Drill hole tests and fluid inclusion investigations both implicate the existence of hydrostatic fluid pressure in situ with respect to salinity of the formation fluid. Matrix permeability and in situ values from hydraulic tests...

Methodology for Investigating the Mechanical Strength of Reforming Catalyst Beads

Reforming catalyst beads must exhibit strong resistance to the mechanical and thermal stresses they experience during their lifetime in a continuous regenerative catalytic unit. An inventory of the mechanical stresses, e. g. compressive, impact and shearing, is presented. It shows that a multitest approach must be designed in order to measure the particle strength and then...

Production froide des huiles visqueuses. Première partie : Observations sur champ

La production froide de certains réservoirs contenant des huiles visqueuses, au Canada et au Venezuela principalement, amène à des productivités et des taux de récupération supérieurs aux prédictions calculées à l'aide des équations habituellement utilisées pour décrire les écoulements classiques. Pour expliquer ces productions anormalement élevées, un certain nombre de m...

Usage of Cfd Modelling for Improving an Fcc Riser Operation

The homogeneity of the regenerated catalyst flow upstream of the feed injectors at the bottom of an industrial FCC (Fluid Catalytic Cracking) riser was thoroughly investigated using several techniques (sampling, temperature and gamma-scan survey). It appeared that marked maldistribution was taking place, due to a bend at the bottom of the riser, which could not be corrected by...

Thermogravimetric Investigation of the Influence of Colloidal Phase on the Processing Properties of Crude Oil Residues

An atmospheric residue, a vacuum residue, a visbreaking residue, the maltene fractions of the residues, mixtures of the atmospheric residue with the vacuum residue and the residue from the supercritical extraction of the vacuum residue as well as residues mixed with dispersing agents were investigated by thermogravimetry at three different heating rates. From that, the activation...

Inertial Effects in Two-Phase Flow Through Fractures

Different approaches for modeling inertial effects during single-phase and two-phase flows through a fracture are presented: inertial factor, passability and Lockhart-Martinelli models. These different approaches are then used to interpret experiments for air/water flow through a rough fracture. For these two-phase flow experiments, the standard relative permeabilities (no...

Improvements of Ebullated-Bed Technology for Upgrading Heavy Oils

Residue from heavy crude oils can be upgraded through various existing processes. Among these processes, the catalytic hydroconversion ebullated-bed process (H-Oil) has the unique feature of deeply converting heavy feedstocks with high impurity contents while operating with a long cycle time. This is accomplished through daily on-line catalyst replacement of a small portion of...

Tangential Motion of Fluids Near Charged Surfaces: Consequences for Wetting

Electrokinetic phenomena all involve tangential motion of fluids with respect to charged solid surfaces or the other way around. A penetrating study involving measurements of surface conduction and molecular dynamics yields mechanistic insight into the slip process which can be useful in interpreting wetting dynamics.Les phénomènes d'électrocinétique font tous référence aux d...