Avoiding Granulation

If the bulk ingredient is suitable then the product can be tabletted directly. A directly compressible form of sucrose is available but is relatively expensive. Fructose and dextrose can also be directly compressed. Specially made, directly compressible forms of the sugar substitutes sorbitol, mannitol and maltitol are available a hygroscopic material like sorbitol would not be easy to wet granulate. 

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While adding the sugar solution to lime, the flask should be continuously rotated to avoid granulation offline. 

Mercury spills should be cleaned up immediately by use of a special vacuum cleaner. The area should then be washed with a dilute calcium sulfide solution. Small quantities of mercury can be picked up by mixing with copper metal granules or powder, or with zinc granules or powder. To avoid or minimize spills, some plants use steel trays as pallets so that a spih, whether of mercury or a mercury compound, is contained on the steel tray. 

The negligible water absorption avoids the need for predrying granules. The low specific heat (compared with polyethylene) enables the polymer to be rapidly heated in injection cylinders, which therefore have a higher plasticising capacity with polystyrene than with polyethylene. The setting-up rates in the injection moulds are also faster than with the polyolefins so that faster cycles are also possible. 

The particular features of the nylons should also be taken into account in extrusion. Dry granules must be used unless a devolatilising extruder is employed. Because of the sharp melting point it is found appropriate to use a screw with a very short compression zone. Polymers of the lowest melt viscosity are to be avoided since they are difficult to handle. Provision should be made to initiate cooling immediately the extrudate leaves the die. 

Conclusion The problem areas are tentatively identified the formulations department is asked to improve the flow properties of the granulate and thus decrease the weight dispersion. The maintenance department will now have to find a proposal for countering the excessive wear on one stamp. Note On more modem, heavily instmmented and feed-back controlled tablet presses, the described deviations would have become more readily apparent, and mechanical damage could have been avoided. 

Flavoring agents proper are commonly volatile oils that have been dissolved in alcohol and sprayed onto the dried granules or have simply been adsorbed onto another excipient (e.g., talc). They are added immediately prior to compression to avoid loss through volatilization. In some cases they may even have some lubricating activity. If the oil normally contains ter-penes, a low terpene grade is better so as to avoid possible deterioration in taste due to terpene oxidation... 

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