Manufacture mining explosives

Shell Loading, Shell Manufacture, Mines, Explosives Manufacture) (Now closed)... 

In the manufacture of explosives, sodium nitrate is used mainly in blasting agents. In slurries and emulsions, sodium nitrate improves stabiUty and sensitivity. It also improves the energy balance because sodium nitrate replaces water, so that more fuel can be added to the formulation. Sodium nitrate reduces crystal size of slurries, which in turn increases detonating speed. In dynamites sodium nitrate is used as an energy modifier. Typical content of sodium nitrate is 20—50 wt % in dynamites, 5—30 wt % in slurries, and 5—15 wt % in emulsions. Sodium nitrate is used also in permissible dynamites, a special type of dynamite for coal (qv) mining. 

Industrial activities involving transportation, pipelines, laboratories, minerals extraction, mining, explosives manufacturing, pyrotechnic manufacturing, or military uses are not considered. 

Detonators for mining explosives are manufactured in various sizes and numbered according to the amount of fulminate which they contain. The charges of fulminate for each size are shown in the following table ... 

The mining explosive Donarit was first used for filling hand grenades and manufacturing demolition charges during World War I. It consisted of... 

The preparation of infusible (loose powder) ammonium nitrate mixtures is usually carried out in the same way as the manufacture of composite mining explosives. Since the military explosives are not very sensitive to mechanical stimulants, and it is important to obtain a high density, mixing is usually performed by edge runner mills. 

Perchlorate explosives for mining, and technical methods of manufacturing chlorate explosives, will be discussed later (pp. 520-521). Mixtures of potassium perchlorate or ammonium perchlorate with plastics or elastomers have recently come into extensive use for jet propulsion (e.g. methyl polymethacrylate, ester resins, and thiokol-rubber). 

The composition of coal mine explosives manufactured and used in Hungary is given in Tables 130 and 131. 

As mentioned before, preparation of AN-FO explosives is usually carried out where they are to be used. The methods are described later in the chapter on the manufacture of mining explosives. 

TM 9-1300-214/TO 11 A-l-34(1967) [Superseding TM 9-1910(1955)], pp7-83 and 7-84 (Dynamites, civil and military) 67) T. Urbanski, "Chemistry and Technology of Explosives , (Translated from Polish by Marian Jurecki), pergamon Press, NY.,. 407 / Mir.inv Fxe c ives with 98 refs) 398-527 (The Manufacture of Mining Explosives, with 14 refs) Note This excellent description was obtd after our write-up on Dynamites was completed) 68) Encyclopedia Britan-nica 8(1967), 974-76 69) E.I. DuPont de... 

Airdox is a blasting device activated by compressed air and manufd by the Cardox Co, Chicago, Illinois. It is particularly suitable for breaking down coal in fiery mines. Descriptions of various types of Airdox are given in the book of J.Taylor P.F.Gay, "British Coal Mining Explosives, G.Newnes, London (1958), 137-42 Air Drying Treatment of Prop el I ants. See under Propellants, Manufacture... 

Transport of liquid nitroglycerine from the nitroglycerine factory to another plant is not allowed in Europe. It can be transported only in mixed forms as dynamites or semi-finished mixtures ready to be used for the manufacture of mining explosives or of double base powders. Only in U.S.A. is the transport of nitroglycerine in special trucks allowed. 

According to the U.S. Standards ammonium nitrate for production of military explosives should contain 99.0% of NH4N03, no more than 0.02% free nitric acid, 0.18% of water-insoluble material, 0.50% of ammonium sulphate and 0.5% of ammonium chloride. The product should be free from alkalis and metal nitrates. A substance of similar purity is used for the manufacture of mining explosives. 

Methods of manufacture ammonium nitrate are described in specialist books on inorganic technology and technology of nitric acid and ammonium salts. However, the method of manufacture of low density prilled ammonium nitrate merits special attention as it can be used to manufacture low density coal mine explosives. 

For some time nitro-solvent-naphtha was a widely used component of explosive compositions. Liquid fractions of the nitrated substance have also been used in the manufacture of mining explosives and even of smokeless powder, as an explosive solvent for nitrocellulose. In the latter case liquid nitro-solvent-naphtha acted as a substitute for part of the nitroglycerine. This type of smokeless powder was also manufactured in Poland in the period between the two World Wars (Karda-szewicz, Markiewicz and Smisniewicz [34]). 

The density of nitropolystyrene is very low, due to its fluffiness . Medard suggested its use in the manufacture of ammonium nitrate mining explosives of low density, hence of a relatively low power. The following figures give some idea of such mixtures ... 

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