| IAEA-CN-115-51 · Present Status Of Environmental Application Of Electron Beam Accelerator In Brazil
C. Lopes Duarte, H. Oikawa, M.l. Nunes Mori, M.H.O. Sampa
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
Av. Lineu Prestes 2.242
05508-000 , São Paulo, SP, Brasil
Abstract: The necessity to decrease the environmental contamination caused by toxic flue gases, liquid and solid
effluent delivered by industries, have resulted in search of new treatment technologies. The oxidation processes
with OH radicals are the most efficient to mineralize organic compounds, and there are various methods to
generate OH radicals as the use of ozone, hydrogen peroxide and ultra-violet radiation (AOP - Advanced
Oxidation Process). The most simple and efficient method for generating OH radicals in situ is the interaction of
ionizing radiation with water. The irradiation of aqueous solutions with high-energy electrons results in the
excitation and ionizing of the molecules and rapid (10-14 - 10-9 s) formation of reactive intermediates. The most
reactive species are the reducing radicals solvated electron (eaq),
and H. atoms and the oxidizing radical
hydroxyl, OH, the unique process that produce the reducing specie e-aq is the electron beam irradiation These
reactive species will react with organic compounds present in industrial effluent inducing their decomposition.
The primary products from water irradiation tend to react with the functional groups present in an organic
molecule rather than with the molecule as a whole. This paper presents the evaluation of ionising radiation
effectiveness in actual effluents from different industries such as chemical, petroleum, wastewater treatment
plant, and drinking water, using Electron Beam Facility with a 1.5 MeV, Dynamitron from Radiation Dynamics
Inc. The ionising radiation was efficient on destroying organic compounds delivered in industrial effluents,
independent on the physical-chemical characteristics and origin. The efficiency of ionizing radiation in presence
of Titanium dioxide (TiO2) catalyzed photoreaction, to treat industrial effluent with high organic pollutant
concentration is discussed. The main objective to combine these technologies is to improve the efficiency for
high-contaminated effluents and decreasing the required absorbed doses for future implementation to large-scale
design.
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