Implications of COD analysis use in the peracetic acid-based wastewater treatment

Autor(es)

Leite, Luan de Souza ^[1] ; Tango, Mariana Daniel ^[1] ; Filho, Jose Antonio Zanetoni ^[1] ; Hoffmann, Maria Teresa ^[1] ; Daniel, Luiz Antonio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Sch Engn, Dept Hydraul & Sanitat, Av Trabalhador Sao Carlense 400, BR-1356659 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: WATER SCIENCE AND TECHNOLOGY; v. 84, n. 5 JUL 2021.
• Citações Web of Science: 0

Resumo

Peracetic acid (PAA) stands out as a safe and environmental-friendly oxidant and disinfectant which has been effectively used in wastewater treatment. Chemical oxygen demand (COD) is a very popular analysis in wastewater treatment, however the interference of residual PAA on the COD measurement is still unknown. In this context, this study investigated the implications of applying the COD analysis in PAA-based treatment. Each 1 mg<bold>L</bold>(-1) of PAA increased the COD concentration around 13.5 mg O-2<bold>L</bold>(-1). Residual PAA and hydrogen peroxide (H2O2) were efficiently neutralized by sodium metabisulfite (SMBS) at the optimal SMBS/PAA ratio of 10.2:1 in a wide pH range (5 to 9). The effect of PAA addition in the COD concentration was evaluated in different water matrices (potassium hydrogen phthalate and wastewater solutions). The COD results with the SMBS addition at optimal SMBS/PAA ratio were lower than the ones without it. It may happen due to the neutralization of residual H2O2/PAA and the complexity of the water matrices which can interfere in the COD results. This study discussed the impact of the residual H2O2/PAA neutralization before the COD analysis and this investigation can be used as a practical guideline for the correct COD measurement in PAA-based treatment. (AU)

• Processo FAPESP: 17/00088-6 - Tratamento de esgoto sanitário: remoção de matéria orgânica, nitrogênio, desodorização do efluente líquido e gasoso, seguido da desinfecção/oxidação por ácido peracético
• Beneficiário: Luiz Antonio Daniel
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 19/05759-1 - Estudo da remoção da Matéria Orgânica Algal (MOA) por coagulação-floculação e emprego de pré-tratamentos
• Beneficiário: Luan de Souza Leite
• Modalidade de apoio: Bolsas no Brasil - Doutorado