초록 ▼

A method to extract and recover plasticizers and their stabilizers from solid propellants, explosives, and pyrotechnics (PEP source compositions) employs near critical liquid (NCL) or supercritical fluid (SCF) CO2 as the solvent. The extraction and ingredient recovery method provides an environmenta

A method to extract and recover plasticizers and their stabilizers from solid propellants, explosives, and pyrotechnics (PEP source compositions) employs near critical liquid (NCL) or supercritical fluid (SCF) CO2 as the solvent. The extraction and ingredient recovery method provides an environmentally acceptable alternative to traditional open burning and destruction of PEP source compositions. CO2 solvent is nontoxic, nonflammable, noncorrosive, inexpensive, and does not generate any additional toxic or hazardous wastes. The solvent is totally inert when it is confined, pressurized, and possibly heated in direct contact with an energetic propellant or munition within a rocket motor or similar pressure vessel. CO2 readily undergoes a gas-to-liquid phase change to NCL conditions when confined and compressed to a pressure of 831 psig or greater at ambient temperature. By further increasing the pressure and temperature of NCL CO2 to 1058 psig and 31.3°C. or greater, respectively, SCF conditions of CO2 are obtained. Either NCL or SCF CO2 has the capability to be a selective solvent for soluble plasticizers (e.g., nitroglycerin) and their stabilizers (e.g., diphenylamines and nitroanilines) from double base and crosslinked double base propellants, munitions and pyrotechnics. All undissolved propellant and munition ingredients are filtered from the NCL or SCF CO2 solvent prior to the pressure reduction/volume expansion recovery cycle. The recovery of soluble plasticizers and stabilizers from a NCL or SCF CO2 solvent system is achieved by allowing the NCL or SCF solvent to undergo pressure reduction and phase change to the gaseous state. The gaseous CO2 is then recycled for additional use in the method.

대표청구항 ▼

A method to demilitarize, extract, and recover near-critical liquid (NCL) carbon dioxide or supercritical fluid (SCF) carbon dioxide soluble plasticizers and their stabilizers from high energy propellant, explosive, and pyrotechnic, (PEP) compositions, said method comprising completing the steps of:

A method to demilitarize, extract, and recover near-critical liquid (NCL) carbon dioxide or supercritical fluid (SCF) carbon dioxide soluble plasticizers and their stabilizers from high energy propellant, explosive, and pyrotechnic, (PEP) compositions, said method comprising completing the steps of: (i) providing a demilitarization unit which comprises a supply and high pressure spray system for NCL carbon dioxide (CO2) or SCF carbon dioxide (CO2) operating under predetermined pressures and temperatures required for maintaining NCL or SCF CO2 conditions; an extraction system including an extraction pressure vessel for containing PEP compositions to be demilitarized, said extraction pressure vessel in communication with said supply and high pressure spray system for NCL CO2 or SCF CO2; a soluble plasticizer and stabilizer recovery system in communication with said extraction pressure vessel for receiving a PEP composition slurry contained in said NCL CO2 or SCF CO2; a carbon dioxide recovery system in communication with said soluble plasticizer and stabilizer recovery system for recovering, drying, and recycling the carbon dioxide recovered to said NCL CO2 or SCF CO2 supply system after completing recompression of said carbon dioxide; (ii) placing a quantity of a PEP composition in said extraction pressure vessel; (iii) admitting a continuous supply of NCL CO2 or SCF CO2 through said high pressure spray system, said NCL CO2 or SCF CO2 impinging upon said PEP composition to erode and complete high particulate comminution of said PEP composition in NCL CO2 or NCF CO2 to form a slurry of said PEP composition in NCL CO2 OR SCF CO2; (iv) pumping said slurry into a solid-liquid filtration chamber of said liquid plasticizer and stabilizer recovery system wherein PEP composition solids are separated from NCL CO2 OR SCF CO2 solution of said soluble plasticizer and stabilizer; (v) passing said NCL CO2 or SCF CO2 solution containing said soluble plasticizer and stabilizer through a liquid-gas expansion system contained in said liquid plasticizer and stabilizer recovery system wherein said NCL CO2 or SCF CO2 is gasified and said liquid plasticizer and stabilizer is released from said NCL CO2 or SCF CO2 containing the same; (vi) recovering said liquid plasticizer and stabilizer; and, (vii) passing carbon dioxide gas through a drying column of said carbon dioxide recovery system then through a filter and a recompression pump which pressurizes said carbon dioxide gas for recycling said recovered carbon dioxide NCL CO2 or SCF CO2 to said supply and high pressure spray system of said demilitarization unit.