This is an award to provide renewal support for a project previously conducted under NSF Grant No. 87-14640 in which an existing 1.5 Mev, 50 ma, electron accelerator located at the Virginia Key Wastewater Treatment Plant in Miami was used to study electron-beam applications in environmental engineering practice. Results confirmed the effectiveness of the electron beam for inactivation of microorganisms in aqueous suspension, destruction of organics contaminants in aqueous solution, and defined reaction rate constants associated with destruction of organic contaminants in water. Research in this project includes expanding studies of dose-destruction relationships for polycyclic aromatic hydrocarbons, identification of reaction mechanisms and byproducts produced by electron beam irradiation, exploring methods for more efficient presentation of the fluid to the beam, study of radical scavengers and enhancers to improve the beam's efficiency, and development of cost models for determination of economic feasibility of electron beam use in environmental engineering practice. Results of this research conducted at a sufficiently large scale to obtain engineering design parameters are likely to be utilized in environmental engineering practice. Potential applications include design of processes and systems for decontamination of surface and groundwaters, destruction of hazardous wastes, treatment of sludges derived from treatment of wastewater to improve their dewaterability and amenability to stabilization processes, disinfection of sludges and processing byproducts and to improve their biodegradability or removal from aqueous solution by other physical or chemical processes.
