Safety in TNT manufacture

The manufacture of TNT is one of die safest operations in the explosive industry. Nevertheless, any negligence about safety regulations may have disastrous consequences. Because the manufacturing process is regarded as safe, the feet must not be overlooked that less experienced personnel may disregard the regulations. 

The spent acid from trinitration has also been the cause of several disasters, although it had been considered safe to handle. The most noteworthy example of this occurred in the Reinsdorf factory in Germany in 1935. The hot spent acid flowed down to open iron tanks, where, as the liquid cooled, a mixture of di- and Tri-nitrotoluenes rose to the surface. It was skimmed off from time to time and transferred to a washing tank, where it was washed with water. On skimming, a rubber glove and a shelf left on the brim of the tank with some cotton wool on it, fell into the tank, The reaction between the spent acid and the rubber and cotton wool initiated violent decomposition and fire. An attempt to extinguish the flames failed, 

Accidents caused by spontaneous explosion of finished TNT are also known. Some of them could be ascribed to the presence of traces of trinitrocresol salts. Others were presumably caused by products of decomposition of trinitrotoluene under the influence of sunlight or alkaline compounds used for deacidification of the TNT. Still others were due to the high sensitiveness of molten TNT to impact. This is why the drying of TNT should be regarded as a very dangerous operation. 

A number of explosions in French TNT factories which occurred during 1917-18, in particular the one at Neuville-sur-Saone (1917) which caused the destruction of the whole plant, were presumably due to the decomposition of the products of reaction of metals, such as lead or iron, with TNT under the conditions described in a paper by Kovache and Thibon [31]. Products readily decomposed, and sensitive to friction and impact, were formed in various parts of the plant where contact between these metals and the TNT could occur in the presence of dilute nitric acid, for example in the TNT washing tank and granulators. Similar compounds were found in a nitrator where part of the TNT in close contact with metals was subjected to the action of nitric acid vapours, for example around the seals at the stirrer shaft bearings. 

Similar compounds were also found in an iron sulphitation tank. TNT is in- 

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