Product separation and discharge of the nitrator

When the reaction has been completed the nitrator contents must remain at rest for some time to allow the product to separate from the spent acid. This may be done in the nitrator itself or the mixture may be transferred into a special settler-separator. The latter is more advantageous if the next nitration is to be carried out in the nitrator immediately after the first reaction. 

The nitrator is discharged either through an outlet located in the bottom (Fig. 34) or by forcing the contents out by means of compressed air (Fig. 35). In the latter case the nitrator lid should fit tightly and the fume outlet should also close tightly with a valve. If the nitrator itself has been used as a separator, the spent 

An advantage of discharge by means of compressed air is that the whole plant can be located in a low building. If the nitrator is emptied through an outlet in its base a high building is necessary. This is of particular importance when underground plant is to be constructed, for the cost rises considerably as the depth in- 

Discharging the nitrator through an outlet has the further drawback that it makes the reactor more difficult to construct. 

In the case of substances that solidify (for example, TNT) all pipes and valves should be provided with heating jackets. If the nitration product solidifies at a 

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