U.S. military installations generate large quantities of energetic material wastes. This includes rocket propellants, explosives and other solid wastes contaminated with those compounds. Currently these wastes are disposed using Open Burn and Open Destruction (OB/OD), but increasingly stringent environmental regulations are curtailing operations. Incineration is not extensively used because of the difficulty in siting needed facilities and the negative public perception. Other alternatives include controlled incineration, wet air oxidation, and supercritical water oxidation. However, these alternative disposal methods are expensive and not economical.
Research activities at the Air Force Research Lab’s Edwards Air Force Base facility generate small quantities of environmentally hazardous energetic wastes. Under a Small Business Innovation Research (SBIR) project awarded by Edwards Air Force Base, CHA developed a microwave disposal system that economically destroys these small quantities of laboratory-derived wastes on-site. Under the Phase II grant, CHA built the prototype for this process and will conduct the field-testing of the prototype by the end of 2014.
The Microwave Energetic Laboratory waste Destruction System (MELDS) consists of three reactor systems: 1) Microwave EM and EMCW Disposal Unit, (2) Microwave Cracker and (3) Microwave Oxidation Unit.The first reactor system destroys solutions or energetic material-contaminated materials wastes. The solid waste is fed into the top of the reactor and is partially oxidized and pyrolyzed by air and microwaves. If the waste is a liquid or a slurry it is pumped into the top of the first reactor where it is subject to the same conditions as the solid waste. The gas and tar produced from the reactor are converted to hydrocarbon gasses in the microwave crackier. These hydrocarbons are completely oxidized in the microwave oxidizer. The exhaust gas from the microwave oxidizer will not contain air pollutants including nitrogen oxides (NOx) and volatile organic compounds (VOCs).