Fractal aggregates evolution during flocculation

- A temporal analysis of fractal aggregates during water flocculation is presented. Water was prepared using kaolin solution and a non-intrusive image-based analysis method was used for two-dimensional fractal dimension assessment (dF). The dF values were determined for aggregates larger than 270 µm...

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Detalles Bibliográficos
Autores: Moruzzi, R. B. [UNESP], de Oliveira, A. L. [UNESP], de Almeida, T. [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/187578
Acceso en línea:http://dx.doi.org/10.1590/0104-6632.20180354s20170231
http://hdl.handle.net/11449/187578
Access Level:acceso abierto
Palabra clave:Flocculation
Fractal aggregates
Temporal evolution
Descripción
Sumario:- A temporal analysis of fractal aggregates during water flocculation is presented. Water was prepared using kaolin solution and a non-intrusive image-based analysis method was used for two-dimensional fractal dimension assessment (dF). The dF values were determined for aggregates larger than 270 µm from 100 images taken in each combination of velocity gradients (Gf) and flocculation times (Tf). The Gf values of 20, 30, 40, 50 and 60 s-1 and Tf values of 2 to 180 minutes were studied, with a ΔTf of 1 minute for 2 ≤ Tf ≤ 10 minutes and a ΔTf of 5 minutes for 10 ≤ Tf ≤ 180 minutes. Results showed that dF tends toward stability from a Tf of 40 minutes, with distinct levels in each Gf. Further, dF values decrease from 1.80 to 1.35 for Gf from 20 to 60 s-1.