Single particle size

In order to elucidate the effect of the particle size during the carbonization process, a so-called granular carbonization experiment was carried out (Figure 6). In this experiment single particle-size fractions of coals of different... 

Note that Sauter s mean diameter in Eq. (1.39) is defined for a range of particle size, which is different from Sauter s diameter in Eq. (1.4), defined for a single particle size. 

Sizing procedures to design a mixer for one closely sized particle settling velocity are modified considerably when there are other solids present. Figure 17 shows the effect of settling velocity on power when there are other solids present in the system. The slope is much less pronounced than it is when a single particle size alone is being suspended. 

The above blends were mixed in powder form prior to compounding on the roll mills. The resultant compounds were compression molded into sheets and were delivered along with the single particle size compounds to AMMRC for ballistic impact evaluation. 

Shapespeare Corporation s Juliet features single particle size and shape measurement together with fractal analysis as well as conventional classical measurements. It also measures size and shape distributions for sets of particles with image manipulation and data graphing capability. 

For a single particle size the power function takes the form of a Lorenzian function. The (Uq term depends inversely on size so the power spectrum plots for different sizes show a shift to higher frequencies as the particle size decreases. In terms of the Brownian motion, smaller particles move more rapidly than large ones. An assembly of particles will have a... 

The sectional approach divides the size distribution into a number of sections, keeping track of the number (or mass or surface area) of all particles in each section and evolving the distribution according to some single particle size within the section. The number of bins... 

The total fraction remaining, F, calculated from the volume of HC1 added is given as a function of dimensionless time, t/t50, where t50 is the time required to dissolve 50% of the CaC03. Calculated curves are also given using the simplified mass transfer model with a single particle size (monodisperse) and with the actual polydisperse size distribution (Table 2). The polydisperse model fits the shape of the curve very well at all times. The monodisperse model is only satisfactory for t/t50 less than 1. 

This finding is being addressed by the ACWA EDS program. The assessment of the particle size reduction needed for proper operation was limited to a single particle size, which was acceptable for the operation. No attempt to identify an optimum particle size is included in the program. 

The other method, which can be used for a single particle size, is called the Weisz-Prater criterion [93] and is found for a first-order reaction by solving Eq. 3.6.a-16 for k ... 

If the particle size range on Equation 10.21 becomes infinitesimal, the obtained efficiency corresponds to a single particle size x and it is known as the grade efficiency, defined by... 

The grade efficiency has become a very useful definition, since most industrial powders consist of an infinite number of differently sized particles. Thus, a single particle size really corresponds to a range of particles having almost similar sizes. Therefore, the gradeefficiency of most separation equipments is a continuous function of x. This function is seldom expressed analytically but graphically. An S-shaped curve is usually obtained for separators in which inertial or gravity body forces perform the separation. 

FIGURE 4.6.2 Schematic of the imaginary Single Particle Size Reduction Process. 

Goossens et al. (1971) modified the equation by Wen and Yu (1966b) on the minimum fluidization velocity for single particle size systems by substituting with the mixture particle density, pp, and the mixture particle size, d , of a binary mixture as follows ... 

For single particle size in a rectangular spouted bed, Anabtawi et al. (1992) showed that the minimum spouting velocity had little difference compared to that in cylindrical beds predictable within the variations from different correlations available for cylindrical beds. A dimensionless correlation for predicting the minimum spouting velocity in a rectangular spouted bed with a mixture of binary particle sizes was recently proposed by Anabtawi (1998). 

Fig. n.22. Arrangement of the apparatus for producing dust fractions of a single particle size. 1) Air columns 2) test tubes 3) trap (catcher) 4) filter 5) rheometer 6) drier 7) frame 8) vibrators 9) LATR control system. 

The electrical-contact properties also depend on the dimensions of the particles. As particle size diminishes, for example, as styrene particles pass from 40 to 4 M, the electrical-contact properties move to the negative side of the series [429, 431]. In vibw of this the developing powder must be of a single particle size otherwise its electrical-contact properties will vary and hence so will the adhesion to the substrate and the quality of the image. 

Lee, D.C. and Georgakis, C. (1981) "A single Particle-Size Model for Sulfur Retention in Fluidized Bed Coal Combustors , AIChEJ, 27, 472-81. 

Fig. 2 HIAC/ROYCO MicroCount 05 (combined light scattering and extinction, single particle sizing sensor)...

These curves compare well with similar curves made by Ruiz-Amil et al [1966]. Figure 6 shows Cesari et al s calculation of the diffraction function O for a 17.8/10 A mixture, using the Allegra formula (full line) and the MacEwan formula (dashed and dotted lines). The maxima coincide well. The MacEwan formula shows some spurious maxima due to the use of a single particle size (see MacEwan and Ruiz-Amil [1959]). 

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