Solid densities

Density (solid particle) Design of treatment or Displacement... 

The term three-phase fluidization requires some explanation, as it can be used to describe a variety of rather different operations. The three phases are gas, liquid and particulate solids, although other variations such as two immiscible liquids and particulate solids may exist in special applications. As in the case of a fixed-bed operation, both co-current and counter- current gas-liquid flow are permissible and, for each of these, both bubble flow, in which the liquid is the continuous phase and the gas dispersed, and trickle flow, in which the gas forms a continuous phase and the liquid is more or less dispersed, takes place. A well established device for countercurrent trickle flow, in which low-density solid spheres are fluidized by an upward current of gas and irrigated by a downward flow of liquid, is variously known as the turbulent bed, mobile bed and fluidized packing contactor, or the turbulent contact absorber when it is specifically used for gas absorption and/or dust removal. Still another variation is a three-phase spouted bed contactor. 

Experiment No. Powder morphology Peak pressure (GPa) Density (% solid)... 

Fig. 3.2. Young s moduli Ec from experiments at T = 500 K are plotted against the calculated moduli ER (Eq. 3.1 T = 500 K). The agreement is good, although apparently more crosslinks are formed than expected from the calculated crosslink density. Solid line Ec = Er...

REAL Density, Solids, Pigment solids. Cost, Pigment... 

Liquid density Solid density Vapor pressure... 

Vapor density Liquid density Solid density 4.86 (air = 1) 1.102 g/cm3 at 25°C No data available... 

Flotation is also used in applications such as the separation of low-density solid particles (e.g. paper pulp) from water and oil droplets from oil-water mixtures. It is not necessary to add reagents if the particles are naturally hydrophobic, as is the case, for example, with oil-water mixtures, as the oil is naturally hydrophobic. 

When separating low-density solid particles or oil droplets from water, the most common method used is dissolved-air flotation. A typical arrangement is shown in Figure 8.12b. This shows some of the effluent water from the unit being recycled, and air being dissolved in the recycle under pressure. The pressure of the recycle is then reduced, releasing the air from solution as a mist of fine bubbles. This is then mixed with the incoming feed that enters the cell. Low-density material floats to the surface with the assistance of the air bubbles and is removed. 

For very small particles or low density solids, the terminal velocity may be too low to enable separation by gravity settling in a reasonably sized tank. However, the separation can possibly be carried out in a centrifuge, which operates on the same principle as the gravity settler but employs the (radial) acceleration in a rotating system (o r) in place of the vertical gravitational... 

The data of Fig. 20 also point out an interesting phenomenon—while the heat transfer coefficients at bed wall and bed centerline both correlate with suspension density, their correlations are quantitatively different. This strongly suggests that the cross-sectional solid concentration is an important, but not primary parameter. Dou et al. speculated that the difference may be attributed to variations in the local solid concentration across the diameter of the fast fluidized bed. They show that when the cross-sectional averaged density is modified by an empirical radial distribution to obtain local suspension densities, the heat transfer coefficient indeed than correlates as a single function with local suspension density. This is shown in Fig. 21 where the two sets of data for different radial positions now correlate as a single function with local mixture density. The conclusion is That the convective heat transfer coefficient for surfaces in a fast fluidized bed is determined primarily by the local two-phase mixture density (solid concentration) at the location of that surface, for any given type of particle. The early observed parametric effects of elevation, gas velocity, solid mass flux, and radial position are all secondary to this primary functional dependence. 

The parametric effect of bed temperature is expected to be reflected through higher thermal conductivity of gas and higher thermal radiation fluxes at higher temperatures. Basu and Nag (1996) show the combined effect (Fig. 23) which plots heat transfer coefficients as a function of bed temperature for data from four different sources. It is seen that for particles of approximately the same diameter, at a constant suspension density (solid concentration), the heat transfer coefficient increases by almost 300% as the bed temperatures increase from 600°C to 900°C. 

TETRA HDS [High density solids] A process for aiding the removal of heavy metals from wastewaters. It is a physical process which controls the characteristics of heavy metal hydroxide precipitates so that they settle quicker. The precipitates have a hydrophobic surface, so they are easy to de-water. Developed and licensed by Tetra Technologies, Houston, TX. Widely used by the iron and steel industry in the United States. Not to be confused with hydrodesulfurization, often abbreviated to HDS. 

Fig. 2. Density of states, transmission and transmittance for the six site chain, as described in the text. The scaled state density (solid black line) exhibits resonances arising from eigenstates on the bridge. The transmittance (solid gray line) drops beyond the limits of the band, and shows only minimal oscillations within the band itself. The behavior of the overall resulting transmission function (dashed line) is determined by the scaled DOS within the band, and by the transmittance outside of the band.

Figure 6.7. Variation of partial current densities (dashed line) and net current density (solid line) with overpotential ry.

Marchand, A. P. 1989. High-energy-density solid and liquid hydrocarbon fuels. Technical Report AFWAL-TR-88-2128 (Feb.). Distribution unlimited. 

Figure 3 Energy of the quasi-free state in rare gas fluids as a function of density. Solid lines represent recent results obtained by field ionization for Ar [61], Kr, and Xe [see Eq. (6)] [63]. Recent theoretical calculations are shown for Ar by the dashed lines [64] and for Ar, Kr, and Xe by the dotted lines [65].

The wedge is usually one-inch-wide and, with side confinement, adequately represents a wedge of infinite width. High-density solid... 

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