Corn starch-based treatment improves rainwater quality

Autor(es)

Kondo Nakada, Liane Yuri ^[1] ; Moruzzi, Rodrigo Braga ^[2]

Afiliação do(s) autor(es)

^[1] Univ Campinas UNICAMP, Fac Engn Civil Arquitetura & Urbanismo, Dept Saneamento & Ambiente, Ave Albert Einstein 951, Cidade Univ, BR-13083852 Sao Paulo - Brazil

^[2] UNESP Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, Dept Planejamento Terr & Geoprocessamento, BR-13506900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: WATER SCIENCE AND TECHNOLOGY-WATER SUPPLY; v. 15, n. 6, p. 1326-1333, DEC 2015.
• Citações Web of Science: 0

Resumo

Rainwater harvesting can provide an alternative water source, which may demand little treatment, depending on the end use. Some starches have been used in water treatment as coagulant/flocculant/filtration aid, and might be applied as primary coagulant. Here, we show direct filtration with hydraulic rapid mixing, using 2-6 mg L-1 cationic corn starch as primary coagulant, considerably improves roof-harvested rainwater quality, achieving removal efficiencies of up to 71.7% of apparent colour, 78% of turbidity, 1.1 log-unit of total coliform, and 1.6 log-unit of Escherichia coli, meeting guidelines for turbidity, even for potable purposes. Cationic corn starch has proved to be a suitable primary coagulant when filtration is performed in a single-layer sand filter (coefficient of uniformity: 1.8, effective particle size: 0.52 mm), at hydraulic loading rate of 450 m day(-1). However, a disinfection unit is required to meet an absence of faecal coliform. (AU)

• Processo FAPESP: 09/11726-7 - Estudo e avaliação do tratamento de água pluvial visando aproveitamento para fins não potáveis empregando filtro de pressão com diferentes meios filtrantes e amido como coagulante primário
• Beneficiário: Liane Yuri Kondo Nakada
• Modalidade de apoio: Bolsas no Brasil - Mestrado