Coagulation and dissolved air flotation as a harvesting method for microalgae cultivated in wastewater

Autor(es)

Leite, Luan de Souza ^[1] ; Hoffmann, Maria Teresa ^[1] ; Daniel, Luiz Antonio ^[1]

Afiliação do(s) autor(es)

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

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF WATER PROCESS ENGINEERING; v. 32, DEC 2019.
• Citações Web of Science: 2

Resumo

Microalgae harvesting is the major bottleneck for biomass production on a large-scale. In this study, coagulation followed by dissolved air flotation (DAF) was used as a harvesting method for Chlorella sorokiniana cultivated in wastewater. The harvesting performance was evaluated using four coagulants (aluminum sulphate, ferric chloride, Tanfloc SG and Zetag 8185) usually used in water or wastewater treatment. All coagulants tested showed high flotation efficiency at different conditions of dosage, pH and flotation velocity. The optimal doses were 10 mg L-1 Zetag 8185; 75 mg L-1 Tanfloc SG; 500 mg L-1 Al-2(SO4)(3), and 1000 mg L-1 FeCl3 at pH 7, which showed the maximum efficiency of 98.4, 94.5, 95.4, 96.7% at 8 cm.min(-1), respectively. Moreover, the photobioreactor effluent quality significantly improved after harvesting tests using the optimal doses. High removal was reached for turbidity (93.7-96.2 %), apparent color (91.7-92.3 %), TKN (90.2-92.6%), total phosphorus (89.4-90.9 %) and TSS (88.6-92.5 %). The use of metal salts requires caution due to the high residual concentration of iron and aluminum in the final effluent. (AU)

• 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
• 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