Agglomeration of powders

Plasma treatment of powder substrates is difficult compared to that of a flat substrate. The main reason for this is the agglomeration of powders and the large surface area per unit mass of the powder. In order to modify the surface, each powder particle must be exposed to plasma. Unexposed regions are seldom modified. Therefore, the surface modification of powder substrates by plasma has to be dealt with differently. 

Essentially any combination of lipids can be used in this method. When working with lipids with a low melting temperature such as PC, care must be taken not to allow the temperature to rise too high, or agglomeration of powder particles will result. Any solvent that will dissolve the lipids can be used, but with ethanol or methanol, very precise regulation of evaporation conditions is required to ensure that dissolution of the sorbitol does not occur as the temperature rises. In these situations... 

These systems are commonly used in the agglomeration of powdered food products. Fine particles are contacted, after their surfaces are made sticky in a controlled manner, to form clusters. After drying and cooling, the clusters have a coarse, porous structure which improves the wettability, dispersibility... 

Swanepoel E, Liebenberg W, de Villiers MM, and Dekker TG. Dissolution Properties of Piroxicam Powders and Capsules as a Function of Particle Size and the Agglomeration of Powders. Drug Dev Ind Pharm 2000 26 1067-1076. 

Another potential use of HP refers to agglomeration of powders that can be used in the elaboration of food bars, tablets, etc. (Mozhaev et al., 1994). Also, culture of microorganisms at HP to produce gases and to prepare phenylalanine methyl ester (used in the synthesis of aspartame) in bioreactors is another use of this new technology in the food area (Mozhaev et al., 1994). 

To overcome these difficulties, it is not surprising that size enlargement by agglomeration of powdered plant nutrients has been investigated almost since the beginning of their use. 

The result of electron-microscopical examinations of zirconium dioxide stabilized by 10 % SC2O3, which was produced by a sol - gel method with application of an alcoholic deaquation, are submitted in Fig. 2. It is found, that the special treatment of the coprecipitated Zr" and oxyhydroxides by the organic solvents lets to produce the oxide powders with primary particles about 100-200 A°. It was found that the agglomeration of powders and the size of primary particles grow with increasing of amount of stabilizing cations. 

Powder - solid Agglomeration of powder by sintering Metals, ceramics, sand, polystyrene, nylon, polyamide, wax no supports porosity shrinkage... 

Agglomeration of powder by binder projection Alumina no supports porosity... 

Agglomeration of powder size-layered sodium disilicate with acidic acrylic acid-maleic acid copolymer can be performed, for example, in high-shear ploughshare mixers. The pulverulent solid raw materials are agglomerated by the liquid components and afterdried in a fluidized bed at 120°C [4]. 

Laboratory Exercise Comparing Methods for Tumbling Agglomeration of Powders... 

When a single screw extruder is used for demanding mixing and compounding operations it is often preferred that the extruder is starve fed rather than flood fed. Flood feeding often results in higher pressures inside the extruder and this can lead to an agglomeration of powdered fillers. When this occurs it may be difficult or... 

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