CLASSIFICATIONS OF SOLIDS

At least two ac tions can take place in the freeboard classification of solids and reaction of solids and gases. 

Classification of solid state reactions according to Boldyrev [100] Initial step Reaction mechanism Examples... 

No single criterion has yet been found to provide a satisfactory basis for the classification of solid—solid reactions. Budnikov and Ginstling [1] (see also Rastogi [1183]) discuss several possible divisions which include ... 

The classification of solid electrolytes is usually based on the ion mainly responsible for the conductivity. There exist ... 

Figure 3.8 shows a classification of. solid catalysts according to their chemical composition. 

Cyclones can be used for the classification of solids, as well as for liquid-solid, and liquid-liquid separations. The design and application of liquid cyclones (hydrocyclones) is discussed in Section 10.4.4. A typical unit is shown in Figure 10.3. 

Liquid cyclones can be used for the classification of solid particles over a size range from 5 to 100 jim. Commercial units are available in a wide range of materials of... 

The electronic conductivity of metal oxides varies from values typical for insulators up to those for semiconductors and metals. Simple classification of solid electronic conductors is possible in terms of the band model, i.e. according to the relative positions of the Fermi level and the conduction/valence bands (see Section 2.4.1). 

EPA OSW Criteria for Classification of Solid Waste Disposal Facilities and Practices Maximum contaminant levels (MCLs) 0.05 mg/L 40 CFR 257, App. I EPA 1993b... 

Figure 49 shows a set of bed collapsing curves for a Geldart Group A-A (for Geldart s classification of solid particles, see Geldart, 1972, 1973) binary solids mixture, two closely sized alumina powders, of average particle diameter 104 and 66 microns, respectively. The curve on the extreme left with 0% fines represents the pure coarse component, which is... 

EPA. 1979d. Criteria for classification of solid waste disposal facilities and practices. U.S. Environmental Protection Agency. Code of Federal Regulations. 40 CFR 257. 

The situation in the solid state is generally more complex. Several examples of binary systems were seen in which, in the solid state, a number of phases (intermediate and terminal) are formed. See for instance Figs 2.18-2.21. Both stoichiometric phases (compounds) and variable composition phases (solid solutions) may be considered and, as for their structures, both fully ordered or more or less completely disordered phases. This variety of types is characteristic for the solid alloys. After a few comments on liquid alloys, particular attention will therefore be dedicated in the following paragraphs to the description and classification of solid intermetallic phases. 

Figure 1 A classification of solid-fuel combustion technologies and solidfuels.

Figure 5 The classification of solid fuel in the three-step model...

EPA-OSW Criteria for Classification of Solid Waste Disposal Facilities and Practices ... 

First, Geldart (1973) and Geldart and Abrahamson (1978) looked at how different kinds of solids behaved when fluidized, and came up with the following simple classification of solids which we now call the Geldart classification, thus Geldart A, B, C, D. These are shown and described in Fig. 20.2. 

In solid-solid separation, the solids are separated into fractions according to size, density, shape, or other particle property (see Size REDUCTION). Sedimentation is also used for size separation, ie, classification of solids (see Separation, size separation). One of the simplest ways to remove the coarse or dense solids from a feed suspension is by sedimentation. Successive decantation in a batch system produces closely controlled size fractions of the product. Generally, however, particle classification by sedimentation does not give sharp separation (see Size measurement of particles). 

Particle Size Distribution. Almost every feed slurry is a mixture of fine and coarse particles. Performance depends on the frequency of distribution of particle size in the feed. Figure 5 shows that whereas all of the coarse particles having a diameter greater than some im are separated, fewer of the very fine particles are, at any given feed rate. The size distribution frequency of particles in feed and centrate for a fine and coarse feed are quite different. More coarse particles separate out than fine ones. Classification of solids by size is often done by centrifugal sedimentation. 

For simplicity, a systematic classification of solid surfaces by heat of immersion values in a single liquid is desirable. Il in (53) predicted on theoretical grounds a decrease in the heat of wetting with increase in the size of the cation in salts or oxides. However, Il in and Kiselev (54) found that the decrease in the heat of immersion from SrSO< to PbS04 to BaS04 predicted by theory is not observed. Heat data for the immersion of a variety of solids in water are listed in Table VII. Here, too, the changes in heat values are not systematic. 

Hazard Classification of Solid Propellants , Paper presented at the Specialist Session on Rocket Motor Safety, 26th JANNAF Meeting, Washington, DC (1970) 23) Anon, Properties of... 

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