Study of sequential disinfection for the inactivation of protozoa and indicator microorganisms in wastewater

Author(s)

Medeiros, Raphael Correa ^[1] ; Daniel, Luiz Antonio ^[2]

Affiliation

^[1] Univ Fed Santa Maria, Dept Ciencias Agron & Ambientais, BR-98400000 Frederico Westphalen, RS - Brazil

^[2] Univ Sao Paulo, Dept Hidraul & Saneamento, Escola Engn Sao Carlos, Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: ACTA SCIENTIARUM-TECHNOLOGY; v. 37, n. 2, p. 203-209, 2015.
• Web of Science Citations: 4

Abstract

Sewage disinfection has the primary objective of inactivating pathogenic organisms to prevent the dissemination of waterborne diseases. This study analyzed individual disinfection, with chlorine and ultraviolet radiation, and sequential disinfection (chlorine-UV radiation). The tests were conducted with anaerobic effluent in batch, in laboratory scale, with two dosages of chlorine (10 and 20 mg L-1) and UV (2.5 and 6.1 Wh m(-3)). In addition, to guarantee the presence of cysts in the tests, 104 cysts per liter of Giardia spp. were inoculated. The resistance order was as follows: E. coli = Total Coliforms < Clostridium perfringens < Giardia spp.. Furthermore, synergistic effects reached 0.06 to 1.42 log of inactivation in sequential disinfection for both the most resistant microorganisms. (AU)

• FAPESP's process: 10/07902-1 - Assessment of the behavior of protozoa Giardia spp. and Cryptosporidium spp. and indicator microorganisms in the wastewater treatment and in river water
• Grantee: Raphael Corrêa Medeiros
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 07/08499-3 - Escherichia coli, Clostridium perfringens and Giardia sp resistance to ozone-ultraviolet radiation and chlorine-ultraviolet radiation sequential disinfection
• Grantee: Luiz Antonio Daniel
• Support Opportunities: Regular Research Grants