Liquid Nitrogen and Water Jet Milling of Energetic Material Production Wastes

Abstract : U.S. Army Ammunition Plants (AAPs) and Load, Assemble and Pack (LAP) facilities generate pyrotechnic, explosive and propellant (PEP) production wastes of diverse nature. These production wastes can be in the form of "off-spec" energetic material (EM), EM contaminated with foreign substances, or processing equipment and materials contaminated with EM. At most of the facilities, these heterogeneous wastes are destroyed or mineralized by open burning/open detonation (OB/OD), a practice which is scrutinized and restricted because of environmental contamination concerns. In recent years several alternative technologies to OB/OD have been identified and developed which can process heterogeneous production wastes to ultimate destruction safely. An eclectic approach to the production waste disposal problem has been used based upon the understanding that no single ,"clean" technology can replace OB/OD. Controlled incineration (CI), wet air oxidation (WAO), hydrothermal oxidation (HTO) and composting have been evaluated and assessed for applicability and efficacy. Each of these alternative destruction technologies for OB/OD require the energetic materials to be reduced to a size compatible with the feed system of the destructor. Because EM production wastes at Army ammunition plants (AAPs) can be contaminated with tramp metals, rocks, glass, wood and other extraneous matter, conventional metal bladed grinding or shearing equipment cannot be safely used to effect diminution. Thus the question is, how can we safely cut up contaminated EM production wastes, without the use of metal bladed equipment? One solution is hydromilling.