The main objective of this project is to demonstrate and validate an integrated nanoscale zero-valent iron – hydrogen peroxide (nZVI-H2O2) technology for rapid and complete destruction of insensitive munitions constituents in explosive production wastewaters. The second objective is to generate cost and performance data that can support future system scale-up and commercialization, regulatory and end user acceptance, and optimization of design and operation to achieve more efficient, sustainable and robust performance. Furthermore, an additional objective is to produce an effluent that is non-toxic to environmental receptors, in compliance with discharge regulations, and suitable for potential re-use within the manufacturing facility.
The technology consists of two synergistic processes that occur sequentially in the same reactor. The process involves the use of nZVI to (1) rapidly decompose munitions compounds in wastewater (the first step), and (2) activate H2O2 to achieve further destruction and mineralization of munitions constituents and their daughter products (the second step). nZVI will not only rapidly transform munitions compounds into intermediates and products that are more prone to oxidation, but also produce dissolved Fe(II) that can initiate Fenton oxidation. H2O2 will be added following nZVI treatment to form Fenton's reagent, producing hydroxyl radical that further destroys munitions compounds and their products. To achieve the objectives above, the research team will conduct a pilot-scale demonstration of the nZVI-H2O2 technology at Picatinny Arsenal, and a supporting, parallel laboratory study at the University of Delaware. Researchers will utilize a wastewater treatment pilot plant at the Armament Research Development and Engineering Center (ARDEC), Picatinny Arsenal, NJ for the technology demonstration.
The suggested technology solution will demonstrate an effective and destructive energetic wastewater treatment process that occupies less area and also combines multiple treatment steps within one reactor. The process is expected to require reduced treatment cycle times compared to current technologies. Additionally, this process offers an advantage over the conventional granular activated carbon (GAC) adsorption process because spent GAC must be disposed of as a hazardous waste once it becomes exhausted . Given that many insensitive munitions compounds are highly water-soluble, difficult to sorb, and can exist at higher concentrations in wastewater, GAC would be a less effective treatment options for these constituents. This project will provide the ammunition production community a preliminary design for consideration when transitioning new explosives to the Industrial Base. (Anticipated Project Completion – 2021)
Akanbi, O.E., I. Kim, D.K. Cha, A.A. Attavane, B.P. Hubbard, and P.C. Chiu. 2022. A Synergistic Nano Zerovalent Iron-Hydrogen Peroxide Technology for Treatment of Insensitive Munitions Wastewater. Propellants, Explosives, Pyrotechnics, 47(6):e202100300. doi.org/10.1002/prep.202100300.