Screening disintegrant

Figure 8-3 Silverson Machines or Ross rotor-stator design (a) head assembly (b) general purpose disintegrating head (c) high-shear screen (d) slotted-screen disintegrating head.

The method used for grinding pressed cakes depends upon the nature of the cake, its purity, residual oil, and moisture content. If the whole cake is to be pulverized without removal of fibrous particles, it may be ground in a hammer mill with or without air classification. A 15-kW (20-hp) hammer mill with an air classifier, grinding pressed cake, had a capacity of 136 kg/h (300 Ib/h), 90 percent through No. 200 sieve a 15-kW (20-lm) screen-hammer mill grinding to 0.16-cm (Vi6-in) screen producea 453 kg/h (1000 Ib/h). In many cases the hammer mill is used merely as a preliminaiy disintegrator, followed by an attrition mill. Typical performance of the attrition mill is given in Table 20-25. A finer product may be obtained in a hammer mill in closed circuit with an external screen or classifier. 

Step 1 Screen diluent Blending diluent + API + 50% disintegrant ... 

For a two-level factorial design, only two excipients can be selected for each factor. However, for the filler-binder, a combination of brittle and plastic materials is preferred for optimum compaction properties. Therefore, different combinations such as lactose with MCC or mannitol with starch can count as a single factor. Experimental responses can be powder blend flowability, compactibility, blend uniformity, uniformity of dose unit, dissolution, disintegration, and stability under stressed storage conditions. The major advantage of using a DOE to screen prototype formulations is that it allows evaluation of all potential factors simultaneously, systematically, and efficiently. It helps the scientist understand the effect of each formulation factor on each response, as well as potential interaction between factors. It also helps the scientist identify the critical factors based on statistical analysis. DOE results can define a prototype formulation that will meet the predefined requirements for product performance stability and manufacturing. 

Blue Streak Dual Screen Pulverizer (Prater Pulverizing Co), Riley Atrita (Reily Stoker Corp), Aero (Foster Wheeler Coip), Rietz Disintegrator (Rietz Mfg Co), Tornado mill (F-J Stokes Coip), Ftiz mill (W.J.Fitzpatrick Co), Turbo-Pulverizers Turbo mills (Pullmann Pulverizer Co), Limited mill (Schutz-0 Neill Co), Pulvocron (Strong Scott Mfg Co), and the Entoleter Impact mills (Entoleter, Inc)... 

To prepare a pulp for Klason lignin analysis, a sample equivalent to approximately 10 g oven-dry is disintegrated in a blender or ground to pass a 10- to 20-mesh screen. Pulps which do not contain coarse fibers or shives and which can be dispersed in sulfuric acid readily may be used without prior disintegration. 

Fig. 54. Disintegrator for dyes (A) feed hopper (B) oscillating feed with magnetic screening device (C) disintegrator (D) motor (E) dust pipe (F) dust chamber (G) filter bags.

It was found that phenol not only depolymerizes coal to colloidal and molecular size, but it also disintegrates coarse coal producing a smaller screen size distribution. This last effect is believed to be similar to that reported by workers at Syracuse University Research Corporation. (11) As a result, the extent and rate of depolymerization were nearly independent of initial particle size. 

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