Sensitiveness of ammonium nitrate

Ammonium nitrate may also be dried in the same driers. Since, however, very large quantities of this substance are processed in factories, the use of a high output drier is necessary. The very low sensitiveness of ammonium nitrate to friction and impact permits the use of steel machinery. 

The sensitiveness of ammonium nitrate to impact is relatively low explosion takes place when a 10 kg weight is dropped from a height of 20 cm. The sensitiveness to shock increases with increasing of temperature, as shown in Table 114, published by Rinkenbach [42] ... 

Cook and Talbot [37] found that the highest sensitiveness of ammonium nitrate to initiation by detonation exists when ammonium nitrate contains 0.75-1.5% of paraffin oil. It can be detonated by a No. 6 detonator. 

The sensitiveness of ammonium nitrate to initiation is increased by the addition to it of explosive substances, such as nitroglycerin, nitrocellulose, or aromatic nitro compounds, or of... 

Fig.3.93 shows the data on the sensitivity of ammonium nitrate, which is an important explosive material. There is a difference in the sensitivity level between crystalline and prilled ammonium nitrate (AN (Prill)), which has many holes in the porous grains that make it more sensitive. The porous prills do not explode completely at a PETN equivalent 1.2g, but they do in the 50/60 steel tube test with an initial explosive booster of 50 g of RDX. 

C. Boyars, Reducing explosion sensitivity of ammonium nitrate fertilizer, Indus. Engin. Chem., Prod. Res. Dev. 15(4), 308—309, 1976. 

Boyars C., Compatibility (Safety) Tests for Taggants in Explosives and Reducing the Explosion Sensitivity of Ammonium Nitrate Fertilizer, Compendiu., Int. Explos. Symp. Fairfa, V., September 18-2, 1995, Treasury Dept., BATE, April 111-115, 1996. 

Evaporators These are used extensively for the concentration of ammonium nitrate, urea, and other chemicals sensitive to heat when... 

It will be clear from the above that the optimum types of oxidising materials are those of highest density and dense forms of ammonium nitrate are always used. The combustibles can be dense also, although it is sometimes necessary to add at least a proportion of the combustible in an absorbent form to ensure adequate sensitiveness. Wheat flour may be regarded as typical of a dense combustible woodmeal is a useful and cheap combustible of intermediate properties. 

Many of the following powdered metals reacted violently or explosively with fused ammonium nitrate below 200°C aluminium, antimony, bismuth, cadmium, chromium, cobalt, copper, iron, lead, magnesium, manganese, nickel, tin, zinc also brass and stainless steel. Mixtures with aluminium powder are used as the commercial explosive Ammonal. Sodium reacts to form the yellow explosive compound sodium hyponitrite, and presence of potassium sensitises the nitrate to shock [1], Shock-sensitivity of mixtures of ammonium nitrate and powdered metals decreases in the order titanium, tin, aluminium, magnesium, zinc, lead, iron, antimony, copper [2], Contact between molten aluminium and the salt is violently explosive, apparently there is a considerable risk of this happening in scrap remelting [3],... 

Slurry explosives consist of saturated aqueous solutions of ammonium nitrate with sensitizing additives.[i-3] Nitrates such as monomethylamine nitrate, ethylene glycol mononitrate, or ethanolamine mononitrate are used as sensitizers. Aluminum powder is also added as an energetic material. Table 4.15 shows a typical chemical composition of a slurry explosive. It is important that so-called micro-bubbles are present within the explosives in order to facilitate the initial detonation and the ensuing detonation wave. These micro-bubbles are made of glass or polymeric materials. 

Inulin nitrate was proposed as a base charge in blasting caps, as a sensitizer for ammonium nitrate in dynamites and as an ingredient of smokeless powders... 

TNT mixtures with ammonium nitrate are more sensitive to impact than TNT itself. As shown by Hackel [49] (Table 49 and Fig. 70) mixtures containing 30-60% of ammonium nitrate are equally as sensitive as picric acid. Mixtures of this kind should not, therefore, be used for filling high initial velocity heavy calibre shells, e.g. armour-piercing shells. 

Medard and Le Roux [1] examined the influence of various methods of mixing on the properties of ammonium nitrate explosives ( Explosifs du type N ). They found that mixing in heavy (5 ton) edge-runners gives explosives of higher sensitiveness and rate of detonation than the same explosives mixed in kneaders of the Werner-Pfleiderer type. 

There are many other ingredients that are added to explosive compositions which in themselves are not explosive but can enhance the power of explosives, reduce the sensitivity, and aid processing. Aluminium powder is frequently added to explosive and propellant compositions to improve their efficiency. Ammonium nitrate (NH4N03) is used extensively in commercial explosives and propellants. It is the most important raw material in the manufacture of commercial explosives and it also provides oxygen in rocket propellant compositions. Some of the properties of ammonium nitrate are presented in Table 2.22. 

Commercial blasting explosives contain ammonium nitrate, wood meal, oil and TNT. A mixture of ammonium nitrate, water and oily fuels produces an emulsion slurry which is also used in commercial blasting explosives. Small glass or plastic spheres containing oxygen can be added to emulsion slurries to increase its sensitivity to detonation. 

Ammonium nitrate based explosives are generally used for quarrying, tunnelling and mining. They are mixtures of ammonium nitrate, carbon carriers such as wood meal, oils or coal, and sensitizers such as nitro-glycol, TNT and dinitrotoluene. These compositions may also contain aluminium powder to improve their performance. 

Nitrotripenta has been prepared by the nitration of tripentaerythritol with 99% nitric acid at 0-10°C. Nitrotripenta is readily soluble in hot benzene and in acetone, soluble in alcohol and chloroform, insoluble in water. Because of its relatively low melting point, nitrotripenta can be melted and poured, and can therefore be used as a coating agent and sensitizer for ammonium nitrate. 

Fukuyama also studied the sensitiveness and the rate of detonation of ammonium nitrate containing water. 

The effect of the temperature on the sensitiveness to shock of ammonium nitrate... 

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