Treatment of a clinical analysis laboratory wastewater from a hospital by photo-Fenton process at four radiation settings and toxicity response

• Published in: Environmental science and pollution research international Vol. 28; no. 19; pp. 24180 - 24190
• Main Authors: Sá, Roberson Davis, Rodríguez-Pérez, Adriana Patricia, Rodrigues-Silva, Fernando, de Paula, Vinicius de Carvalho Soares, Prola, Liziê Daniela Tentler, de Freitas, Adriane Martins, de Carvalho, Karina Querne, de Liz, Marcus Vinicius
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2021; Springer Nature B.V
• Subjects: Acute toxicity; Advanced Oxidation/Reduction Technologies: An Perspective from Iberoamerican Countries; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Biochemical oxygen demand; Biodegradability; Biodegradation; Chemical oxygen demand; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Ferrous ions; Germination; Hydrogen peroxide; Iron; Laboratories; Organic matter; Oxygen; Phenols; Photooxidation; Phytotoxicity; Radiation; Seeds; Toxicity; Waste Water Technology; Wastewater; Wastewater treatment; Water Management; Water Pollution Control; Mild radiation; AOP; Intense radiation; Biodegradability; Lactuca sativa; Daphnia magna
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-021-12860-7

The photo-Fenton process was performed with four radiation settings to treat clinical analysis laboratory wastewater (CALWW) from a hospital, with the aim of evaluating its treatability and acute toxicity response in Daphnia magna and Lactuca sativa . The experiments were performed in a borosilicate bench-scale conventional reactor for 320 min. The light radiation was suspended 13 cm from the CALWW surface for mild radiation or immersed into the matrix for intense radiation. All photo-Fenton experimental conditions were set at pH 3.0, 15 mg L -1 of Fe 2+ , and initial H 2 O 2 of 300 mg L -1 . The initial Fe 2+ concentration was converted to Fe 3+ ion in the first 15 min of photooxidation for all processes. Furthermore, the intense radiation processes regenerated Fe 2+ faster than other systems. Neither mild UVA-Vis nor mild UVC-Vis radiation significantly treated the organic matter or phenols. However, mild UVC-Vis resulted in a higher biodegradability transformation rate (biochemical oxygen demand/chemical oxygen demand 0.51), indicating that it could treat more recalcitrant organic matter than mild UVA-Vis. Intense radiation proved to be more efficient, with a chemical oxygen demand removal rate of 95% for intense UVA-Vis and 99% for intense UVC-Vis treatments. All treatments reduced acute toxicity in D. magna . Moreover, photo-Fenton treatment by intense UVA-Vis decreased toxicity ~98%, compared to mild and intense UVC-Vis, ~75%. Both of the mild radiation treatments inhibited the germination of L. sativa seeds. The intense UVA-Vis photo-Fenton treatment was the only setting that removed phytotoxicity, resulting in a non-significant effect, and the intense UVC-Vis treatment inhibited the seed growth.