Removal of protozoan (oo)cysts and bacteria during microalgae harvesting: Outcomes from a lab-scale experiment

Autor(es)

de Oliveira, Gabriela Laila ^[1] ; Erbetta Sueitt, Ana Paula ^[1] ; dos Santos, Priscila Ribeiro ^[1] ; Leite, Luan de Souza ^[1] ; Daniel, Luiz Antonio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Sch Engn, Dept Hydraul & Sanitat, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Chemosphere; v. 286, n. 3 JAN 2022.
• Citações Web of Science: 0

Resumo

The efficiency of microalgae harvesting on the removal of Giardia spp. cysts, Cryptosporidium spp. oocysts, total coliforms, Escherichia coli, Enterococcus spp. and Clostridium spp. was assessed in lab-scale experiments (Jartest and Flotatest) using effluent from a flat panel photobioreactor used for Chlorella sorokiniana cultivation. Three harvesting methods were evaluated: (1) flocculation induced by pH modulation followed by sedimentation (pHSED), (2) flocculation induced by pH modulation followed by dissolved air flotation (pH-DAF), and (3) coagulation using an organic coagulant (Tanfloc SG) followed by dissolved air flotation (Coag-DAF). The results indicated that the three harvesting methods were efficient in removing protozoan (oo)cysts and bacteria, achieving percentages of removal higher than 97% for all the analyzed pathogens. Among the three methods, pHSED showed the best removal performance: 99.60% (2.5 log) for Giardia spp. cysts, 100% (>6.3 log) for total coliforms, 100% (>4.6 log) for Escherichia coli, 100% (>5.8 log) for Enterococcus spp. and 99.96% (3.6 log) for Clostridium spp. Clostridium spp. seemed to be more tolerant to the harvesting methods than the other groups of bacteria analyzed in the study, and its presence was positively correlated to the presence of Giardia spp. cysts. (AU)

• Processo FAPESP: 17/14620-1 - Otimização do cultivo de Chlorella sorokiniana em fotobiorreator flat panel e colheita para sua utilização como fertilizante
• Beneficiário: Luan de Souza Leite
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 15/02073-0 - Remoção de nutrientes em fotobiorreator tubular alimentado com efluente de reator UASB tratando água negra
• Beneficiário: Ana Paula Erbetta Sueitt
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/50522-0 - Contaminação ambiental pelos protozoários Giardia spp. e Cryptosporidium spp. e por Ascaris suum: desafios de detecção, remoção e inativação das formas infectantes
• Beneficiário: Regina Maura Bueno Franco
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/50351-4 - Recovering nutrients and carbon from concentrated black water: a sustainable decentralized approach for wastewater treatment
• Beneficiário: Luiz Antonio Daniel
• Modalidade de apoio: Auxílio à Pesquisa - Regular