Abstract: In emulsion blend explosives, the replacement of coarse salt particles, e.g., prills, by fines, i.e., particles which pass a No. 50 U.S. sieve, increases the water resistance of the explosive without deleteriously affecting its shelf life provided that the explosive, prior to such replacement, is storage-stable as determined by the Salt Extraction and lead compression tests described herein. Products containing a combination of whole and crushed ammonium nitrate prills, and emulsions made with an anionic emulsifying agent such as a fatty acid salt, are preferred. Depending on the fines content and chemical composition, other properties such as sensitivity to initiation and detonation velocity also may be improved.

Abstract: In emulsion blend explosives, the replacement of coarse salt particles, e.g., prills, by fines, i.e., particles which pass a No. 50 U.S. sieve, increases the water resistance of the explosive without deleteriously affecting its shelf life provided that the explosive, prior to such replacement, is storage-stable as determined by the Salt Extraction and lead compression tests described herein. Products containing a combination of whole and crushed ammonium nitrate prills, and emulsions made with an anionic emulsifying agent such as a fatty acid salt, are preferred. Depending on the fines content and chemical composition, other properties such as sensitivity to initiation and detonation velocity also may be improved.

Abstract: Explosives that are sensitized blends of a water-in-oil emulsion and inorganic nitrate, e.g., AN, particles, such as AN or ANFO prills, have improved stability when their structure hinders the loss of water from the aqueous emulsion phase and transportation of such water across the oil phase to the nitrate particles. Use of an anionic emulsifying agent comprising a fatty acid salt, e.g., as formed in situ during the formation of the emulsion, is the preferred way of forming such a blend-stabilizing structure. Emulsion/nitrate blends stabilized in this manner make satisfactory storage-stable packaged products. Emulsion/nitrate blends made with a new low-viscosity emulsion containing essentially all of the oil required to oxygen-balance the blend and a proportionately larger amount of anionic emulsifying agent to stabilize the emulsion structure constitute preferred bulk products owing to their greater adaptability to pumping.