Granular characteristics

Relation of the granularity characteristic curves to the elutriation times at... 

Granularity characteristic curves of an identical quartz dust obtained by... 

Fig 12 Relation of the granularity characteristic curves to the elutriation times at 5.5 hours and at 1.5 hours in the Gonell Separator... 

Another important class of dryer is the fluidized-bed dryers. Some designs combine spray and fluidized-bed dryers. Choice between dryers is usually based on practicalities such as the materials handling characteristics, product decomposition, product physical form (e.g., if a porous granular material is required), etc. Also, dryer efficiency can be used to compare the performance of different dryer designs. This is usually defined as follows -. 

Essentially all the ammonium sulfate fertilizer used in the United States is by-product material. By-product from the acid scmbbing of coke oven gas is one source. A larger source is as by-product ammonium sulfate solution from the production of caprolactam (qv) and acrylonitrile, (qv) which are synthetic fiber intermediates. A third but lesser source is from the ammoniation of spent sulfuric acid from other processes. In the recovery of by-product crystals from each of these sources, the crystallization usually is carried out in steam-heated sa turator—crystallizers. Characteristically, crystallizer product is of a particle size about 90% finer than 16 mesh (ca 1 mm dia), which is too small for satisfactory dry blending with granular fertilizer materials. Crystals of this size are suitable, however, as a feed material to mixed fertilizer granulation plants, and this is the main fertilizer outlet for by-product ammonium sulfate. 

Classification of size enlargement methods reveals two distinct categories (8,39). The first is forming-type processes in which the shape, dimensions, composition, and density of the individual larger pieces formed from finely divided materials are of importance. The second is those processes in which creation of a coarse granular material from fines is the objective, and the characteristics of the individual agglomerates are important only in their effect on the properties of the bulk granular product. 

Identification. Weld decay characteristically produces distinct, narrow zones of disintegration immediately adjacent and parallel to the weldment (Fig. 15.4). Attack will occur on either side of the weld. The weld itself and surrounding metal will be unattacked. The corroded area frequently has a granular or sugary appearance and feel. This is due to corrosion along the boundaries of individual grains that causes them to be released from the metal surface. Affected metal may have lost its metallic ring. 

Lin, S. H. and Chen, Y. V., Adsorption and desorption characteristics of 1,1-dichloro-1-fluoroethane by granular activated carbon and activated carbon fiber, J. Environ. Sci. Health, Part A Toxic / Hazard Subst. Environ. Eng., 1996,31(6), 1279 1292. 

Observable Characteristics - Physical State (as shipped) Granular or powdered solid some may appear glassy Color. White Odor. None. 

Filtration operations are capable of handling suspensions of varying characteristics ranging from granular, incompressible, free-filtering materials to slime-like compositions, as well as finely divided colloidal suspensions in which the cakes are incompressible. These latter materials tend to contaminate or foul the filter medium. The interaction between the particles in suspension and the filter medium determines to a large extent the specific mechanisms responsible for filtration. 

Each application for carbon treatment must be cognizant of the characteristics of the contaminant to be removed and designed with the proper carbon type in order to attain optimum results. Basically, there are two forms of activated carbon powdered and granular. The former are particles that are less than U.S. Sieve Series No. 50, while the latter are larger. The adsorption rate is influenced by carbon particle size, but not the adsorptive capacity which is related to the total surface area. —... 

Granular media filtration is used for treating aqueous waste streams. The filter media consists of a bed of granular particles (typically sand or sand with anthracite or coal). The anthracite has adsorptive characteristics and hence can be beneficial in removing some biological and chemical contaminants in the wastewater. This material may also be substituted for activated charcoal. 

But how can we estimate the pressure-loss coefficient A Stegmaier - has summarized horizontal transport for several fine-granular solids by a correla tion which contains some characteristics of the material. The same idea has been used by Weber, who has found a correlation of the pressure-loss coefficient for vertical pneumatic conveyance based on data measured by Flatow. In order to express these models, we first introduce two dimensiitnless numbers... 

US Mil Spec MIL-M-51273, Mercuric Nitrate, Monohydrate, Analyzed Reagent (15 Jan 1968) contains the following requirements Mercuric nitrate, monohydrate shall be a white granular powder and conform to these chemical characteristics Assay as Hg(N03)2.H20, 99.0% min residue after ignition, 0.029% max chloride,... 

From several values given above, the characteristic granularity curves were set up as function of the elutriation time ... 

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