Pellets spherical agglomeration

In this section three miscellaneous topics in the area of agglomeration shall be discussed, namely, dry pelletization, spherical agglomeration in liquid suspension, and spontaneous or inadvertent agglomeration of fine particles. 

Common practice to normalize the compressive strengths of spherical agglomerates of different sizes is to divide individual loads at failure by (pellet diameter)2 (cf. Section 4.1). This treatment of pellet strength data, however, assumes a uniform radial distribution of bonds within the agglomerates. That is, in the generalized relationship between load at failure and agglomerate diameter,... 

A final technique presented for the continuous production of solid dosage forms is extrusion/ spheronization—a technique producing spherical agglomerates of very uniform size. The process is based on low-pressure extrusion and shaping the moist, plastic extrudate into spheres in a spheronizer. These spheres (pellets) are, in most cases, coated after drying and filled into hard gelatin capsules or compressed into... 

Fig. 23 Pellets prepared by spherical agglomeration. Overview about ascorbic acid pellets prepared from powder of a mean particle diameter of 8.8 pm. The bar is 1 mm (A). SEM picture from left (B). Ascorbic acid pellet prepared from powder of a mean diameter of 8.8 pm without the addition of povidone (C). Pellet from left prepared with the addition of 2% PVP (D). Ascorbic acid pellet prepared from powder of a mean particle diameter of 3.0 pm without the addition of povidone (E). Pellet from left with the addition of 2.0% povidone (F).

Fig. 25 Differences observed in the deformation of substances during tableting. Potassium chloride at low (A) and high com-pressional forces (B), pellets prepared by spherical agglomeration in a tablet surface (C) and in the inner part of a broken tablet (D), surface of an acetyl salicylic acid (ASA) tablet containing 10% sodium carbox5methyl starch (E) and the same surface after moistening with a finger (F). (From Ref...

They are harder compared with pellets produced by powder layering. Their appearance is similar to pellets obtained by fluidized-bed granulation using the so-called rotating fluidized bed. " Owing to the fact that ideally round pellets are desired, several attempts were made to quantify their roundness. " The spherical agglomeration is a completely different method that is employed to develop pellets that are round and uniform in size. In this, particles are agglomerated in suspension. ... 

When compressing pellets into tablets, their deformation depends on their hardness. When hard pellets produced by spherical agglomeration are compressed the single pellets are still visible at the surface... 

Name for many different types of agglomerate. Most commonly used in the iron ore industry for spherical agglomerates formed by growth agglomeration in discs, cones, or drums and in the animal feed industry for cylindrical agglomerated products by pelleting. Sometimes synonymous with agglomerate. 

Synonymous with spherical AGGLOMERATE. (See also PELLET)... 

Originally in the iron ore industry any method producing spherical AGGLOMERATES by TUMBLE or GROWTH AGGLOMERATION. (See also PELLETIZING)... 

A successful variation of oil agglomeration was used for removal and dewatering of soot from a 1—3% soflds suspension consisting of <5 — fim particles in refinery process waters (Fig. 8). Heavy oil was added to the dilute slurry and intensely agitated in a multistage mixer. The soot agglomerated with the oil to form 3—5 mm pellets that were easily screened from the water (95). The pellets contained only 5—10% water. The process was modified to recover very fine clean coal, and it produced highly uniform, hard, spherical pellets 1—2 mm in diameter. 

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