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Influencing factors suspension density

The key factors influencing the purity drop phenomena are considered at first. They must be the factors which enh ce primary nucleation or growth of attached tiny crystalline particles on the seed crystals therefore a list of factors would include solution supercooling (or supersaturation), agitation speed, suspension density, mass of seed crystals, pretreatment of seed crystals, cooling rate and phase equilibria of given systems. Effects of these factors investigated in literature are examined separately. [Pg.63]

As explained above two of the main influence factors are fixed for ensuring better control of crystallisation. One is AC, which in practice is set to about a half of the metastable range, the other is the crystal mass mj or the crystal surface area A, set to values between 15 and 25wt% expressed as suspension density. As consequence, both factors cannot be taken for influencing the CSD and the mean crystal size. [Pg.194]

The discussion so far relates to the motion of a single spherical particle in an effectively infinite expanse of fluid. If other particles are present in the neighbourhood of the sphere, the sedimentation velocity will be decreased, and the effect will become progressively more marked as the concentration is increased. There are three contributory factors. First, as the particles settle, they will displace an equal volume of fluid, and this gives rise to an upward flow of liquid. Secondly, the buoyancy force is influenced because the suspension has a higher density than the fluid. Finally, the flow pattern of the liquid relative to... [Pg.161]

Statistical mechanics was originally formulated to describe the properties of systems of identical particles such as atoms or small molecules. However, many materials of industrial and commercial importance do not fit neatly into this framework. For example, the particles in a colloidal suspension are never strictly identical to one another, but have a range of radii (and possibly surface charges, shapes, etc.). This dependence of the particle properties on one or more continuous parameters is known as polydispersity. One can regard a polydisperse fluid as a mixture of an infinite number of distinct particle species. If we label each species according to the value of its polydisperse attribute, a, the state of a polydisperse system entails specification of a density distribution p(a), rather than a finite number of density variables. It is usual to identify two distinct types of polydispersity variable and fixed. Variable polydispersity pertains to systems such as ionic micelles or oil-water emulsions, where the degree of polydispersity (as measured by the form of p(a)) can change under the influence of external factors. A more common situation is fixed polydispersity, appropriate for the description of systems such as colloidal dispersions, liquid crystals, and polymers. Here the form of p(cr) is determined by the synthesis of the fluid. [Pg.49]


See other pages where Influencing factors suspension density is mentioned: [Pg.437]    [Pg.240]    [Pg.437]    [Pg.150]    [Pg.3598]    [Pg.560]    [Pg.273]    [Pg.548]    [Pg.143]    [Pg.219]    [Pg.5]    [Pg.392]   


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Suspension density

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