A New Model for the Kinetics of Bacteria Disinfection with UV Radiation

M. LABAS, C. MARTÍN Y A. CASSANO

San Diego, USA

Congreso; AOT´s-10 Advanced Oxidation Technologies For Water and Air Remediation; 2004

An alternative technology to the conventional disinfection processes, the application of UV radiation was used. The employed subrogated bacteria were Escherichia coli. The polluted water was treated with low wavelength (253.7 nm) radiation in a laboratory reactor where all the significant operating variables were carefully measured and controlled. A modification of the Series-Event Model was used to interpret the experimental data which were collected employing four different levels of the incident radiation fed to the reactor. The developed model is based on a rather complex dependence with respect to the Escherichia coliEscherichia coli. The polluted water was treated with low wavelength (253.7 nm) radiation in a laboratory reactor where all the significant operating variables were carefully measured and controlled. A modification of the Series-Event Model was used to interpret the experimental data which were collected employing four different levels of the incident radiation fed to the reactor. The developed model is based on a rather complex dependence with respect to the Escherichia coliEscherichia coli concentration and to the radiation that is effectively absorbed by the bacteria which was precisely quantified. The mathematical description has three parameters: (i) the threshold limit of damage for the bacteria which was found to be equal to 2, (ii) the kinetic constant and (iii) the order with respect to the photonic absorption rate by the bacteria which was found equal to 0.2. 99.99 % plus inactivation was always reached in all cases for short effective contact times and predictions from the model agree very well with experimental data in the whole range of investigated variables