ANFO
Quick Summary
ANFO, an acronym for ammonium nitrate/fuel oil, is a compound used as a commercial explosive and in improvised bombs. It was developed in 1955 and revolutionized the explosives industry. ANFO is created by mixing 94% prilled ammonium nitrate with 6% fuel oil. Prilled ammonium nitrate, originally developed for fertilizers, is porous and absorbs oil well, creating a more sensitive explosive.12
ANFO is widely used in open-pit mines for coal and iron, as well as in construction for tasks like road building. It can also be used in smaller underground mines. ANFO and similar water-gel explosives now account for at least 70% of high explosive consumption in the United States.23
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miningUnit operations…nitrate and fuel oil (ANFO), which is transported by tanker truck and pumped into the holes. When filled with ANFO, a blasthole 400 mm (about 16 inches) in diameter and 7.5 metres (about 25 feet) deep can develop about one billion horsepower. It is incumbent upon those involved in…
Read More…nitrate and fuel oil (ANFO), which is transported by tanker truck and pumped into the holes. When filled with ANFO, a blasthole 400 mm (about 16 inches) in diameter and 7.5 metres (about 25 feet) deep can develop about one billion horsepower. It is incumbent upon those involved in…
Read More- miningHorizontal openings: drifts
…by blasting agents based on ammonium nitrate (AN; chemical formula NH4NO3) and fuel oil (FO; chemical formula CH2). Neither of these components is explosive by itself, but, when mixed in the proper weight ratio (94.5 percent AN, 5.5 percent FO) and ignited, they cause the following chemical reaction:
Read More…by blasting agents based on ammonium nitrate (AN; chemical formula NH4NO3) and fuel oil (FO; chemical formula CH2). Neither of these components is explosive by itself, but, when mixed in the proper weight ratio (94.5 percent AN, 5.5 percent FO) and ignited, they cause the following chemical reaction:
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coal miningDrilling and blasting…nitrate and fuel oil (ANFO) in dry mix, slurry, or emulsion form. It is common to have a bulk-explosive truck drive into the area where holes have been drilled to fill holes with custom-designed explosive mixtures.
Read More…nitrate and fuel oil (ANFO) in dry mix, slurry, or emulsion form. It is common to have a bulk-explosive truck drive into the area where holes have been drilled to fill holes with custom-designed explosive mixtures.
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tunnels and underground excavationsConventional blasting…nitrate and fuel oil (called AN-FO), which in granular form (prills) can be blown into the drill hole by compressed air. While AN-FO-type agents are cheaper, their lower power increases the quantity required, and their fumes usually increase ventilating requirements. For wet holes, the prills must be changed to a…
Read More…nitrate and fuel oil (called AN-FO), which in granular form (prills) can be blown into the drill hole by compressed air. While AN-FO-type agents are cheaper, their lower power increases the quantity required, and their fumes usually increase ventilating requirements. For wet holes, the prills must be changed to a…
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