Uses of ammonium nitrate

Its main use is as a fertilizer. Since it is hygroscopic in nature it is diluted with j-1 % Mg to soak up water and prevent caking. Other uses are indicated in Table 3.10. 

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A small but important use of ammonium nitrate is in the production of nitrous oxide during the 1980s consumption for this purpose averaged about 30,000 t. The gas is generated by controlled heating of ammonium nitrate above 200°C. Nitrous oxide is used primarily as an anesthetic and as an aerosol propellant for food products (see Anesthetics Aerosols). 

Special authorisations are available for manufacture at the site of use of ammonium nitrate/fuel oil and certain slurry explosives provided that the equipment used and its position on the site are suitable. 

Ammonium nitrate has an 82 18 fertilizer explosive end use ratio. The chief use of ammonium nitrate until after World War II was as an explosive. Although it still accounts for more than 75% of all explosives, its major use is now as a fertilizer because of its high nitrogen content, 33.5% N. 

Other uses of ammonium nitrate are in the manufacture of nitrous oxide, an anesthetic, and as a component of freezing mixtures. 

Another advance in this field was the use of ammonium nitrate as a chief component. In 1867 Ohlsson and Norrbin [3] patented a mining explosive—Ammoniak-krut (ammonium powder, cf. p. 331) consisting of ammonium nitrate mixed with 5-10% charcoal. Ohlsson and Norrbin added to this mixture 10-30% nitroglycerine to make detonation easier and to increase the power of the explosive. Similarly Nobel began to add ammonium nitrate to his dynamites. 

Another method was to dip blackpowder pellets in paraffin wax. This rendered them waterproof, and also surrounded them with a cooling sheath . A blasting powder made in this form called Bobbinite was introduced in Great Britain. It will be discussed later. These half-measures brought little improvement and attention was centred on the use of ammonium nitrate explosives. 

The explosive violence of the second reaction accounts for the use of ammonium nitrate as a component of dynamite and its use in the devastating bomb that destroyed the Federal Building in Oklahoma City in 1995. Ammonium nitrate has a high nitrogen content (33.5% by mass) and is highly soluble in water. These characteristics make it attractive as a fertilizer which is its principal use. 

World demand for nitric acid will continue to be largely dependent upon demand for solid ammonium nitrate fertilizer and nitrogen fertilizer solutions that incorporate ammonium nitrate. Since the early 1980 s, urea has been displacing ammonia nitrate as a fertilizer. The resulting reduction in demand for nitric acid has been partially offset by the increased use of ammonium nitrate in explosives and by the growth in production of polyurethane foams and nylon-6,6. World nitric acid production declined by about 5% between 1987 and 1999, but it is projected to increase marginally by 2005. The declines occurred mainly in the former Soviet Union, Eastern Europe and Western Europe. Production increases occurred mainly in the United States and Africa91,104. Nitric Acid production in the United States is listed in Table 9.11. 

The hygroscopicity of ammonium nitrate is its great drawback. The probleir. occurred particularly with the use of ammonium nitrate mining explosives their storage and use in damp places. Tlic usual method of reducing hygroscopicity consists in incorporating small proportions of calcium, zinc and iron salts of fatty acids, usually stearic acid. 

The hygroscopic ty of ammonium nitrate is a great drawback in explosives containing this salt. Jt limited the use of ammonium nitrate explosives, and only relatively recently methods were found of reducing the hygroscopicity of ammonium nitrate explosives. 

A small-scale but important use of ammonium nitrate is for the preparation of inhalation grade nitrous oxide for use as an anaesthetic. This is achieved by heating pure ammonium nitrate to about 200-250°C (Eq. 11.53), which gives nitrous oxide virtually free of nitric oxide or... 

How can the use of ammonium nitrate by terrorists be prevented The most logical approach is to desensitize or neutralize the compound s ability to act as an explosive, but to date no satisfactory way has been found to do so without diminishing its value as a fertilizer. A more passive method is to add to the fertilizer an agent known as a taggant, which would allow law enforcement to trace the source of an ammonium nitrate explosive. A number of European countries now forbid the sale of ammonium nitrate without taggants, although the U.S. Congress has yet to pass such a law. 

The primary use of ammonium nitrate is the manufacture of fertilizers. In 2005, about 2 million metric tons (2.2 million short tons) of ammonium nitrate fertilizer was used in the United States. The compound is added to soil to provide the nitrogen that plants need to grow. It may he used by itself or in combination with another nitrogen-rich compound, urea, in a mixture known as UAN. 

Some other uses of ammonium nitrate include the following ... 

Ihe problem of burning ammonium nitrate and its mixtures is widely described in the excellent monograph by Glazkova (18). The problem is not only of great theoretical but also of practical importance. It is connected with the use of ammonium nitrate explosives in coal-mines and their ability to bum which creates an additional danger of their use. In the present book it is discussed in Chapter XIX on Mining Explosives. 

Give one reason for continued use of ammonium nitrate as a fertilizer and one reason why it should be under greater control. 

Packing, Handling, Transportation, Bulk Storage and Use of Ammonium Nitrate Fertilizer. The Fertilizer kistitute, 1015 18th Street N. W., Washington, D.C., U.S.A. 

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