Granule shapes

V = average fluid velocity through bed D = granule diameter fr = granule shape factor g = gravitational constant t = time... 

It is necessary to note that the Langeven function L depends on variable D, over which the integration is conducted, Vg — %D3/6. Using this ratio and experimental dependence M(H), it is possible to get experimental size dispersion and then compare it with results of electron microscopy measurements. In the case when deviation of the granule shape from spherical is insignificant, such comparison testifies the applicability of the given model... 

Binders (to hold the granule shape) include ethyl acetate, and rosin (also called colophony the sap or sticky substance from pine or spruce trees). 

Figure 8-34 Viscosity and Granule Appearance in the Viscoamylograph Test of a 5% Suspension of Waxy Corn in Water. A = viscosity curve, B = granule shape and size, C = magnified portion of curve to indicate cohesiveness, a = unswollen granule, b = swollen granule, c = collapsed granule, d = entwined collapsed granules. Source Reprinted from L.H. Kruger and R. Murray, Starch Texture, in Rheology and Texture in Food Quality, J.M. deMan, P.W. Voi-sey, V.F. Raspar, and D.W. Stanley, eds., 1976, Aspen Publishers, Inc.

Starch is a fine white powder that is odorless and tasteless. It is composed of very small spherical or elliptical granules. The botanical origin of the starch material determines the granule shape and size, and these characteristics are summarized in Table 1. It is insoluble in... 

Type of Starch Extracted from Granule shape Granule size (pm)... 

The primary particle size distribution of the powder, as well as the granule shape, has an influence upon the attainable density and strength of the molded article. The static friction between the individual particles and the compression mold can be reduced by lubricating additives, which largely suppress the development of structural stress. 

Dependence of degradation rates on flow velocity indicates rate limitation by transport processes, e.g. reported by Sivavec and Homey (1995) or Burris et al. (1995) for the degradation of trichloroethene (TCE) by zerovalent iron in batch reactors. Even if there has been no real explanation for the different degradation behaviour at the two column experiments, it must be dependent on the characteristics of the granular iron, because of the similar experimental conditions. The diverse granulate shape or the distribution of reactive surface as well as mineral precipitations usually present in iron... 

Plastics raw material in granular form. Granules shaped cylindrically or like lentils, usually... 

Figure 5-13 demonstrates the influence on the drying rate of granulate shape, kind of air flow, air temperature and velocity, on a belt dryer using granulated particles (clay, pigments, plastic filler, etc.). 

Fig. 5-13. Dependency of the drying rate on granulate shape type product, air flow, air temperature...

Shape Density — This measurement can be of significant moment to adsorption performance despite it being relevant to only a single granule. This is because, for a given granule shape and size, shape density depends upon porosity of the activated carbon. For a cylindrical shape as 4 x 6 Tyler mesh size, a typical value is 1.4 g/cc (87 Ib/CF) to 1.5 g/cc (94 Ib/CF). 

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