Solid bulk density

In their second method, as in the case of a vertical riser, the total pressure drop along the spout height is composed of (i) a solids static head equivalent to the dispersed-solids bulk density, (ii) an acceleration pressure drop, and (iii) a solids friction loss due to relative motion of the particles with respect to the gas and to the spout wall. Thus,... 

Using the vertical profile of v and Ua (estimated from the measured pressure drop profile as explained in Section IV,A), the authors evaluated the right-hand side of Eq. (74) for each 2-in. increment of the spout, assuming constant pba over this increment. This value, on substitution in Eq. (70) along with the measured total pressure drop for the increment, gave the pressure drop per foot due to the solids bulk density in the spout, from which the voidage profile was calculated. The results agreed well with those from method (a). 

A single-stage duct-type electrostatic precipitator contains five plates that are 10 ft high, 20 ft long, and spaced 9 in. apart. Air contaminated with gypsum dust enters the unit with an inlet loading of 53 gr/ft and a velocity through the unit of 5 ft/s. The solids bulk density is 47 Ib/ft. ... 

Particle mean diameter Solids bulk density Solids density Angle of repose... 

Plots corresponding to Fig. 2 of bed height L, voi-dage , and liquid-solids bulk density, each as a function of superficial velocity, are shown in Figs. 3, 4, and 5, respectively. For a total mass M of particles, the volumetric particle concentration in either a fixed or a fluidized bed is given by... 

Figure 5 Liquid-solids bulk density as a function of liquid...

A few deductions may be made from these equations. At great depth, the mean pressure p depends only on the radius R and the wall friction coefficient pi, not on the depth below the surface. A smooth wall leads to higher pressures than a rough wall. The pressures all vary linearly with the solid bulk density p, so this is a key parameter in any silo evaluation. 

Solid Density. SoHds can be characterized by three densities bulk, skeletal, and particle. Bulk density is a measure of the weight of an assemblage of particles divided by the volume the particles occupy. This measurement includes the voids between the particles and the voids within porous particles. The skeletal, or tme soHd density, is the density of the soHd material if it had zero porosity. Fluid-bed calculations generally use the particle... 

Specific gravity is direcdy related to the bulk density of waste fuels prepared ia a variety of ways. Solid oven-dry (OD) wood, for example, has a typical bulk density of 48.1 kg/m (301b/ft ). In coarse hogged form, eg, <1.9-cm minor dimension, this bulk density declines to about24kg/m (151b/ft ). In pulverized form, at a particle size <0.16 cm, this bulk density declines to 16—19 kg/m (10—12 Ib/ft ). Similar relationships hold for municipal waste, agricultural wastes, and related fuels. 

Bulk density is 1.49 kg/L for 57% solids slurry with a Mg(OH)2 loading of 0.85 kg/L. The properties of some magnesium hydroxide slurries are given in Table 12. 

Foam Insulation Since foams are not homogeneous materials, their apparent thermal conductivity is dependent upon the bulk density of tne insulation, the gas used to foam the insulation, and the mean temperature of the insulation. Heat conduction through a foam is determined by convection and radiation within the cells and by conduction in the solid structure. Evacuation of a foam is effective in reducing its thermal conductivity, indicating a partially open cellular structure, but the resulting values are stiU considerably higher than either multilayer or evacuated powder insulations. 

Static This is a dense bed of solids in which each particle rests upon another at essentially the settled bulk density of the solids phase. Specifically, there is no relative motion among solids particles (Fig. 12-26). 

The physical properties of spray-dried materials are subject to considerable variation, depending on the direction of flow of the inlet gas and its temperature, the degree and uniformity of atomization, the solids content of the feed, the temperature of the feed, and the degree of aeration of the feed. The properties of the product usually of greatest interest are (1) particle size, (2) bulk density, and (3) dustiness. The particle size is a function of atomizer-operating conditions and also of the solids content, liquid viscosity, liquid density, and feed rate. In general, particle size increases with solids content, viscosity, density, and feed rate. 

P. True not bulk) density of solids or liquid drops kg/m Ibm/ft Ibm/ft ... 

Bulk density is easily measured from the volume occupied by the bulk solid and is a strong func tion of sample preparation. True density is measured by standard techniques using liquid or gas picnometry Apparent (agglomerate) density is difficult to measure directly. Hink-ley et al. [Int. ]. Min. Proc., 41, 53-69 (1994)] describe a method for measuring the apparent density of wet granules by kerosene displacement. Agglomerate density may also be inferred from direcl measurement of true density and porosity using Eq. (20-42). 

TABLE 21-13 Air Velocities Needed to Convey Solids of Various Bulk Densities ... 

A useful approximation of B for a conical hopper is B = 22f/a, where a is the bulk density of the stored product. The apparatus for determining the properties of solids has been developed and is offered for sale by the consulting firm of Jenike and Johansen, Winchester, Massachusetts, which also performs these tests on a contract basis. The flow-factor FF tester, a constant-rate-of-strain, direct-shear-type machine, gives the locus of points for the FF cui ve as well as ( ), the... 

Dissolved Solids Boiling Pt/Freezing Point For Liquids/Solid Mixtures Bulk Density Total Solids Content Solids Size Distribution Suspended Solids Content Suspended Solids Settling Rate Dissolved Solids Content Free Water Content Oil and Grease Content Viscosity For Gases Density... 

The ratio of p JPmin be as high as 1.52 depending on the material. Consequently, when bulk densities are reported it is important to note whether the value was determined under loose or tapped conditions, along with the mean particle size. Most literature values report an average bulk density that is representative of the material most often handled. Loose solids may be broadly characterized according to their bulk densities ... 

Moisture can significantly affect loose materials, particularly their flowability. Low temperatures, particle bridging, and caking can alter interparticle void fractions and cause dramatic changes in bulk density. Moisture becomes bound to solids because of mechanical, physicochemical, and chemical mechanisms. Moisture retained... 

When we consider many particles settling, the density of the fluid phase effectively becomes the bulk density of the slurry, i.e., the ratio of the total mass of fluid plus solids divided by the total volume. The viscosity of the slurry is considerably higher than that of the fluid alone because of the interference of boundary layers around interacting solid particles and the increase of form drag caused by particles. The viscosity of a slurry is often a function of the rate of shear of its previous history as it affects clustering of particles, and of the shape and roughness of the particles. Each of these factors contributes to a thicker boundary layer. 

Bulk density, soil - Mass of dry soil per unit bulk volume (combined volume of soil solids and pore space). 

The reactor volume is calculated from Mj and the bulk density of the catalyst material, (-r ) depends not only on composition and temperature, but also on the nature and size of the catalyst pellets and the flow velocity of the mixture. In a heterogeneous reaction where a solid catalyst is used, the reactor load is often determined by the term space velocity, SV. This is defined as the volumetric flow at the inlet of the reactor divided by the reaction volume (or the total mass of catalyst), that is... 

Bulk density Apparent density of bulk solids, kg m". ... 

FIG. 6 Density profile of a hard sphere fiuid near a hard wall. The bulk density is pd = 0.6. The curve gives the results of the lOZ equation with the PY closure and the circles give the simulation results. The results obtained using the HAB equation together with the MV closure are very close to the solid curve whereas the results obtained from the HAB equation with the HNC and PY closures are too large and too small, respectively. 

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