Kinetic assessment of antibiotic resistant bacteria inactivation by solar photo-Fenton in batch and continuous flow mode for wastewater reuse
| Autor: | J.A. Sánchez Pérez, I. De la Obra Jiménez, J.L. Casas López, G. Rivas Ibáñez, B. Esteban García |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Environmental Engineering
Cefotaxime Hydraulic retention time Continuous operation 0208 environmental biotechnology 02 engineering and technology Wastewater 010501 environmental sciences Solar irradiance 01 natural sciences Water Purification Escherichia coli medicine Waste Management and Disposal Effluent 0105 earth and related environmental sciences Water Science and Technology Civil and Structural Engineering Bacteria Chemistry Ecological Modeling Hydrogen Peroxide Pulp and paper industry Pollution Anti-Bacterial Agents 020801 environmental engineering Disinfection Batch processing Water treatment medicine.drug |
| Zdroj: | Water Research. 159:184-191 |
| ISSN: | 0043-1354 |
| DOI: | 10.1016/j.watres.2019.04.059 |
| Popis: | The presence of antibiotic resistant bacteria in municipal wastewater treatment plants represents a real risk to human health. For the first time, this paper shows that the inactivation rate of cefotaxime resistant bacteria is the same as total bacteria when secondary effluents are treated by the solar photo-Fenton process. To obtain this result, an exhaustive and comparative kinetic study on the inactivation of both total and cefotaxime resistant bacteria (Total coliform, Escherichia coli and Enterococcus sp) was carried out, taking into account the effects of the main operation conditions, such as solar irradiance and iron concentration, and operation mode (batch and continuous). In all the operation conditions studied, no significant differences were found between the first order inactivation rate constants, ki, of total and cefotaxime resistant bacteria. Additionally, ki increased with solar irradiance and iron concentration. As for the effect of the operation mode, the main finding of this work is much quicker inactivation in continuous flow mode than in batch mode, pointing out its potential application at large scale. The best continuous operation condition to inactivate the bacteria to the detection limit (1 CFU mL−1), was at 22.4 min of hydraulic residence time with 5 mg Fe2+ L−1 and 30 mg H2O2·L−1. This treatment time is approximately a third of that reported in batch mode. The efficiency, in terms of figure of merits, of the continuous flow operation was 2.7 m2 of solar collector area to reduce one log of E. coli concentration per m3 of treated water and per hour, in comparison with 2137 m2 calculated for batch operation under the same solar UVA irradiance, 30 W m−2. This paper encourages research into continuous solar disinfection processes due to its enhanced efficiency with regard to the commonly used batch wise operation and shows that efficient removal of total bacteria ensures the removal of antibiotic resistant bacteria. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect