A. C. Alvarez

A fast inverse solver for the filtration function for flow of water with particles in porous media

Models for deep bed filtration in the injection of seawater with solid inclusions depend on an empirical filtration function that represents the rate of particle retention. This function must be calculated indirectly from experimental measurements of other quantities. The practical petroleum engineering purpose is to predict injectivity loss in the porous rock around wells. In this work, we determine the filtration function from the effluent particle concentration history measured in laboratory tests knowing the inlet particle concentration. The recovery procedure is based on solving a functional equation derived from the model equations. Well-posedness of the numerical procedure is discussed. Numerical results are shown.

Determination of the textural characteristics of carbon samples using scanning electronic microscopy images: comparison with mercury porosimetry data

In this paper, scanning electron microscopy (SEM) images of carbon samples were analysed, and some textural characteristics were obtained and compared with those determined using mercury porosimetry data. Fractal dimensions were calculated from both mercury porosimetry and SEM images as methods for characterising the porous distribution (heterogeneity) of the samples. Lacunarity is easily determined from SEM images as a measure of the degree of heterogeneity of a porous surface. A relationship between the lacunarity and the fractal dimensions calculated using both methods is shown. Pore-size distributions were also determined from the analysis of SEM images. We show that the analysis of SEM images is a valuable complement to mercury porosimetry measurements and a useful tool for the characterisation of porous surfaces. This method offers the possibility of evaluating the features of porous materials and comparing the results to those obtained using mercury intrusion analysis.

Step Soliton Generalized Solutions of the Shallow Water Equations

Generalized solutions of the shallow water equations are obtained. One studies the particular case of a generalized soliton function passing by a variable bottom. We consider a case of discontinuity in bottom depth. We assume that the surface elevation is given by a step soliton which is defined using generalized solutions (Colombeau 1993). Finally, a system of functional equations is obtained where the amplitudes and celerity of wave are the unknown parameters. Numerical results are presented showing that the generalized solution produces good results having physical sense.

Porous Media Deposition Damage from Injection of Water with Particles

Severe fall of injectivity in porous rock occurs from the practice in offshore fields of injecting sea water containing organic and urineral inclusions. In general, injection of a poor quality water in a well curtails its injectivity. The injectivity loss is assumed to be due to particle retention in the porous rock .

The Riemann Solution for Carbonated Waterflooding

We develop a Riemann solver for transport problems related to oil recovery. We consider one dimensional incompressible flow in porous media involving several chemical components, namely

Analytic regularization of an inverse filtration problem in porous media

H_2O

Analytical and numerical solutions for carbonated waterflooding

,

Mathematical Theory of Two-Phase Geochemical Flow with Chemical Species

H^

Low Salinity Carbonated Waterflooding

,

Determining the Filtration and Permeability Reduction Functions for Flow of Water with Particles in Porous Media

OH^-