Granulometric Properties

F. Garcia, N. LeBolay, C. Frances, Rheological behaviour and related granulometric properties of dense aggregated suspensions during an ultrafine comminution process. Powder Tech., 130, 407-414 (2003). 

Changes in the coal s particles size, which are either intended (e.g., grinding) or are attributed to intrinsic processes in the gasifer (e.g., fragmentation), need to be quantified for reliable technical adaptation. Last but not least, the interaction of the coal bulk with the applied machinery will result in wear, which should be assessed before plant construction. The most relevant calculation procedures and coal tests regarding these granulometric properties will be presented in the following sections. 

However, granulometric composition is also dependent on several technological factors, more specifically, the properties of source material and binder liquid, their ratio and particle size of material on the plate. 

DETERMINING THE TYPE OF SOIL. Every soil cousists of mineral particles of varying sizes. The ratio of the particle sizes present in a soil largely determines the properties of the soil. The granulometric composition (texture) of a soil can he precisely determined hy laboratory tests (sieve and sedimentation analysis). Large particles are determined hy sieving and finer ones by sedimentation. The soil type is apparent from the ratio of the individual granulometric fractions. 

A variety of techniques are available for the characterisation of particle size distributions but, because of the large size distribution of solids in water and wastewater, no single analytical method can be used. Besides their physico-chemical properties (stability, settleability, etc.), heterogeneous fractions have interesting optical properties. This is the reason why optical methods take an important place among granulometric methods (Table 5). 

The hygroscopic water is water contained in air-dried soils. The content of this water varies depending on the relative humidity and on the soil properties particularly the granulometric composition and humus content of the soil affect its amount. 

Mechanical properties and an optical transparency of polymer films, their phase structure and crystallinity, and also communication of mechanical and optical properties with a microstructure of polyethylene and granulometric stmcture of modifying powders nc-Si were observed. 

Study of metal-salt reactions in molten salts is of great practical and scientific value in the electrolysis of refi-actory metals and in the study of the electrochemical properties of compounds of low oxidation states which are formed in contact with metal. Metal-salt reaction has a great influence on current efficiency and the granulometric composition of niobium powders during electrolysis of the KCl-KF- K2NbF7 melt with... 

In general it can be stated that with feed material which may cause difficulties on account of low friction due to its specific material properties and/or granulometric composition it is possible to achieve distinct improvements in mill throughput, operational behaviour and specific power consumption by the addition of hard coarse particles. Improvements can similarly be obtained when dealing with feed material that tends to become solidly compacted on the grinding ring because of its moisture content and composition, e. g., too high a proportion of clay... 

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