Free flowing explosives

M. Aoki Sh. Motoya, Free-Flowing Explosive Compositions , JP 4444 (1962) ... 

In large-scale blasting processes in open pit mining and quarrying, rows of nearly vertical boreholes are drilled parallel to the quarry face the diameter of each borehole is 3-8 in. (in Germany more often 3-4 in.), while the borehole length is over 10 m. The holes are filled with explosive and stemmed. -> Free-flowing Explosives or pumped -> Slurries can be applied. 

Some important general properties of nano-energetic materials (this term refers to nanoparticles of explosives, oxidizers and fuels either in free flowing or encapsulated form) are ... 

Consistency of Commercial Explosives. Com" mercial expls of today are available in a free flowing form such as dry sand, representing one extreme, and in a form as cohesive as raw rubber, at the other extreme. There are also hard plastic expls, such as Blasting Gelatin and some... 

Non-cartridged commercial explosives which can be poured into boreholes, mostly ammonium nitrate explosives containing anticaking agents. When ammonium nitrate became commercially available as - Prills (porous pellets), ANFO blasting agents could also be utilized in the free-flowing form -> also Pellets. 

Certain types of powder-form explosives contain moisture repelling additives such as stearates in paraffinated cartridges they can be applied even under wet conditions. Non-cartridged powder form explosives must be free-flowing (-> ANFO). 

Solids being transferred vary in size of particles dusty material sometimes results in dust explosions. The materials can also vary in abrasiveness, be free-flowing, or cohesive, or friable. Wet or sticky materials, however, are often a problem if they are not continuously cleaned from the belt surface. 

Properties Wh. free-flowing ctyst. powd. sol. 2.5% in water m.w. 146.14 dens. 1.34 (18 C) bulk dens. 40-45 Ib/ft (loose) melt vise. 4.54 cP (160 C) vapor pressure 0.106 mm Hg m.p. 152-153 C b.p. 337 C with decomp. flash pt. (TCC) 196 C pH 3.2 (1 g/l in water) > 99.9% assay Toxicology LD50 (oral, mice) 1900 mgAg si. acute toxicity eye and upper respiratory tract irritant mild skin irritant Environmental Aquatic toxicity LC50 (fathead minnows, 96 h) 88 mg/l Precaution Combustible under severe dusting conditions may form explosive mixts. in air incompat. with strong oxidants slowly decomp, above b.p. 

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