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Porous media unconsolidated

For an unconsolidated porous medium with uniform pore size distribution, the ratio of VJHa approaches its maximum value much more rapidly than that found in a medium where pore size distribution is nonuniform, leading to the significant variation of water saturation in the contaminated zone. [Pg.195]

Washing. As ice moves upward through the column, it behaves as an unconsolidated porous medium and carries brine with it, held by viscous and capillary forces. The flow is entirely laminar, because the Reynolds number based on particle diameter is always less than 0.05. The brine is carried thus at the surface and in the fillets between the particles. The downward flowing wash water moves between the particles and mixes with the brine mainly by molecular diffusion. Salt will diffuse from the brine to the wash water. [Pg.102]

A. K. Verma, K. Pruess, C. F. Tsang, and P. A. Withespoon, A Study of Two-Phase Concurrent Flow of Steam and Water in an Unconsolidated Porous Medium, in Heat Transfer in Porous Media and Particulate Flows, ASME HTD, (46) 135-143,1984. [Pg.730]

Porous medium is a material consisting of a solid matrix with interconnected pores. The interconnected pores are responsible for allowing a fluid to traverse through the material. For the simplest situation, the medium is saturated with a single fluid ( single fluid flow ). In multiphase fluid flow, several fluids (liquids and/or gas) share the open pores. Porous media are classified as unconsolidated and consolidated. [Pg.233]

Porosity. The fraction of total (bulk) volume occupied by the voids is defined as the porosity of the porous medium. A porous medium can be classified according to the type of porosity involved. In sandstone and unconsolidated sand, the voids are between sand grains, and this type of porosity is known as intergranular. Carbonate rocks are more complex and may contain more than one type of porosity. The small voids between the crystals of calcite or dolomite constitute intercrystalline porosity (47). Often carbonate rocks are naturally fractured. The void volume formed by fractures constitutes the fracture porosity. Carbonate rocks sometimes contain vugs, and these carbonate rocks constitute the vugular porosity. Still some carbonate formations may contain very large channels and cavities, which constitute the cavernous porosity. [Pg.296]

Porous Medium A solid containing voids or pore spaces. Normally such pores are quite small compared with the size of the solid and well-distributed throughout the solid. In geologic formations, porosity may be associated with unconsolidated (uncemented) materials, such as sand, or a consolidated material, such as sandstone. [Pg.755]

The distribution of the oil, gas and water in the porous medium was better understood when Botset and Wyckoff (9) carried out the first experiments on relative permeability. They showed that either oil or gas would flow only if a specific minimum saturation of the phase in question existed in the flow region of the porous material. Some of the early workers also recognized that either the oil or gas droplets could be discontinuous, and in this condition, would be hard to displace by flowing water because of the Jamin effect. In 1927, Uren and Fahmy (10) investigated a number of "factors which affect the recovery of petroleum from unconsolidated sands by waterflooding. Table 1 lists these factors and the general results observed by Uren and Fahmy. With one exception (rate), the results observed by Uren and Fahmy are similar to generalizations which most experts in this field claim today after work of more than 50 years. [Pg.15]

The porous medium consists of unconsolidated Ottawa sand contained in a cylindrical lucite or lexan polycarbonate core holder. [Pg.252]

The correlations represented by Eqs. 5.26a through 5.26e can be extended to interpolate for polymer concentrations between 1,000 and 2,000 ppm by use of a correlation based on the modified Blake-Kozeny model for the flow of non-Newtonian fluids. 62 Eq. 5.27 is an expression for A bk derived from the Blake-Kozeny model. Note that all parameters are either properties of the porous medium or rheological measurements. Eq. 5.27 underestimates A/ by about 50%. However, Hejri et al. 6 were able to correlate pBK and A for the unconsolidated sandpack data with Eq. 5.28. Eqs. 5.27 and 5.28, along with Eq. 5.24, predict polymer mobility for polymer concentrations ranging from l.,000 to 2,000 ppm within about 7%. [Pg.22]

Fig. 5.80 shows results illustrating behavior in porous medium for a polyacrylamide/Cr(III)/redox system. The data were taken by flowing the gel system at a steady rate through an unconsolidated sandpack. The gel system was mixed at the inlet of the sandpack with an in-line mixer. Pressure drop was measured along the sandpack and converted to apparent viscosity by use of Darcy s law. Apparent viscosity is plotted vs. distance at different times for the gel system up to about 240 hours. [Pg.54]

There are various conceptual ways of describing a porous medium. One concept is a continuous solid with holes in it. Such a medium is referred to as consolidated, and the holes may be unconnected (impermeable) or connected (permeable). Another concept is a collection of solid particles in a packed bed, where the fluid can pass through the voids between the particles, which is referred to as unconsolidated. Both of these concepts have been used as the basis for developing the equations which describe fluid flow behaviour. ... [Pg.58]

The term porosity refers to the fraction of the medium that contains the voids. When a fluid is passed over the medium, the fraction of the medium (i.e., the pores) that contributes to the flow is referred to as the effective porosity of the media. In a general sense, porous media are classified as either unconsolidated and consolidated and/or as ordered and random. Examples of unconsolidated media are sand, glass beads, catalyst pellets, column packing materials, soil, gravel and packing such as charcoal. [Pg.63]

Figure 13-1 Porous media, (a) Consolidated medium (b) unconsolidated medium. Figure 13-1 Porous media, (a) Consolidated medium (b) unconsolidated medium.
The last model assumes that porous media can be idealised as parallel capillaries along the direction of flow. Porous media such as adsorbents and catalysts are usually formed by compressing small grains into pellet, and for such particles the model for unconsolidated media will be particularly useful. There are a number of equations available in the literature to describe the Knudsen flow through a unconsolidated medium. They are identical in form and differ only in the numerical proportionality coefficient. [Pg.365]


See other pages where Porous media unconsolidated is mentioned: [Pg.376]    [Pg.907]    [Pg.65]    [Pg.720]    [Pg.333]    [Pg.230]    [Pg.130]    [Pg.176]    [Pg.209]    [Pg.225]    [Pg.227]    [Pg.13]    [Pg.297]    [Pg.188]    [Pg.169]    [Pg.391]    [Pg.398]    [Pg.178]   
See also in sourсe #XX -- [ Pg.391 ]




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Media Unconsolidated

Porous media

Unconsolidated

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