Active ingredients and combustibles

Woodmeal is of particular importance among combustible ingredients since apart from its stabilizing effect, discussed above, it enables the mixture to be retained in a loose state with a low density. Charcoal is another ingredient sometimes added. 

The addition of aluminium to increase the heat of the explosion and, in consequence, the power of the explosive, as practised for some time, is now believed to be too dangerous. Ammonium nitrate explosives with aluminium are permitted only for rock work in opencast mining (e.g. quarries) or underground, where there is no methane. 

Ammonium nitrate explosives usually contain a certain amount of nitro compounds from mononitro (e.g. nitronaphthalene) to trinitro compounds (e.g. trinitrotoluene). 

Some ammonium nitrate explosives used in the U.S.S.R. contain a small amount of paraffin (0.5-1 %) to reduce the hygroscopicity of the ammonium nitrate. 

Recently Hino and Yokogawa [59] found that by adding less than 1% surface active agents, an improvement of transmission of detonation of ammonium nitrate explosives can be achieved. 

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