Agglomeration processes powder feeding

In the plating process it is essential to guarantee a homogenous blending besides homogenous addition/distribution of the liquid material. The liquid feeding can be carried out by inlet lances, injectors or nozzles, while agglomeration of the plated powder material has to be suppressed by a chopper or cutter. 

Nodulizing is another process of size enlargement by fusion. A rotary kiln like those used in the cement industry is employed. The product formed is uniform with a hard surface and is more dense than the sintering process. Agglomeration by partial melting requires a feed in powder form. 

Porous structures in green agglomerates can be achieved if the feed particles are preagglomerated (Fig. 5.49) or consist of hi- or multi-modal particle size fractions. Another method is the production of loose packings by sedimentation. Then, to retain the open porosity, the sintering process must be carried out at a low temperature and for a short time or, to obtain more open pores, pore forming additives are mixed with the powder. 

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