| Full text | |
| Author(s): |
Total Authors: 2
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| Affiliation: | [1] Univ Estadual Paulista Unesp, Inst Geociencias & Ciencias Exatas, Ave 24-A, 1515, CP 178, BR-13506900 Rio Claro, SP - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | Brazilian Journal of Chemical Engineering; v. 35, n. 3, p. 1029-1037, JUL-SEP 2018. |
| Web of Science Citations: | 1 |
| Abstract | |
Abstract The reversibility of aggregates during flocculation was investigated. The stable diameter (d) and the power law slope coefficient of the particle size distribution (β) were applied to follow re-formation after breakage. A non-intrusive image-based technique was used for monitoring flocs. Aggregates were formed by adding alum [Al2(SO4)3·18H2O] by the sweep-coagulation mechanism to two synthetic waters, prepared from kaolin (Fluka) and humic acid (Aldrich Chemical). Velocity gradients (G) varied from 20 to 120 s-1 during experiments, and the rupture occurred under controlled conditions. After rupture, the initial condition was reinstated and reversibility analyzed. Results pointed out the irreversibility of breakage for both Al-kaolin and Al-humic flocs. The stable diameter of aggregates after breakage (d2) varied from 157 to 132 µm for Al-humic and from 233 to 123µm for Al-kaolin aggregates, using G from 20 to 120 s-1. β 2 values varied from 1.2 to 4.6 for Al-humic and from 0.6 to 7.7 for Al-kaolin. (AU) | |
| FAPESP's process: | 13/25641-9 - Procedure etermination for image acquisition to determine flocculent particles size in static reactors |
| Grantee: | Pedro Augusto Grava da Silva |
| Support Opportunities: | Scholarships in Brazil - Scientific Initiation |