TY - JOUR
T1 - Impact of hydrodynamic conditions on the structure of clay-based tailings aggregates flocculated in freshwater and seawater
AU - Leiva, Williams H.
AU - Piceros, Eder
AU - Robles, Pedro
AU - Jeldres, Ricardo I.
N1 - Funding Information:
Williams H. Leiva thanks the financial support of CSIRO Mineral Resources, Chile. Williams H. Leiva and E. Piceros acknowledge the infrastructure and support of the Programa de Doctorado en Ingeniería de Procesos de Minerales of the Universidad de Antofagasta. Ricardo I. Jeldres acknowledges funding support from ANID Fondecyt 1211606 and Centro CRHIAM Project ANID/Fondap/15130015. Pedro Robles thanks the Pontificia Universidad Católica de Valparaíso for the support provided.
Funding Information:
Williams H. Leiva thanks the financial support of CSIRO Mineral Resources, Chile. Williams H. Leiva and E. Piceros acknowledge the infrastructure and support of the Programa de Doctorado en Ingenier?a de Procesos de Minerales of the Universidad de Antofagasta. Ricardo I. Jeldres acknowledges funding support from ANID Fondecyt 1211606 and Centro CRHIAM Project ANID/Fondap/15130015. Pedro Robles thanks the Pontificia Universidad Cat?lica de Valpara?so for the support provided.
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2022/1
Y1 - 2022/1
N2 - The impact of shear rate on the structural properties of aggregates obtained during the flocculation of clay-based tailings with an anionic polyacrylamide was analyzed. The effects generated in industrial water (IW) and seawater (SW) were compared. Flocculation-sedimentation batch tests were performed to know aggregate size distribution, hindered settling rate, and internal structure of flocs expressed through their fractal dimension. The aggregate properties were characterized by the Focused Beam Reflectance Measurement (FBRM) and Particle Vision Microscope (PVM) techniques. The aggregate size distribution showed a bimodal behavior, where a portion of the particles does not flocculate properly unless the shear rate increases during flocculation. On the other hand, the size and quantity of coarse aggregates strongly depend on the mixing intensity. The use of seawater led to a reduction in the size of aggregates. It is suggested that this is a result of polymer coiling, which leads to a decreased ability to form polymeric bridges and thus less particle capture. The fractal dimension of aggregates shows that while the shear rate increases, the aggregates are less compact, with structures possibly more open and further away from a solid spherical body. The greatest reduction occurred in industrial water, related to the larger size of the structures in a low salinity environment.
AB - The impact of shear rate on the structural properties of aggregates obtained during the flocculation of clay-based tailings with an anionic polyacrylamide was analyzed. The effects generated in industrial water (IW) and seawater (SW) were compared. Flocculation-sedimentation batch tests were performed to know aggregate size distribution, hindered settling rate, and internal structure of flocs expressed through their fractal dimension. The aggregate properties were characterized by the Focused Beam Reflectance Measurement (FBRM) and Particle Vision Microscope (PVM) techniques. The aggregate size distribution showed a bimodal behavior, where a portion of the particles does not flocculate properly unless the shear rate increases during flocculation. On the other hand, the size and quantity of coarse aggregates strongly depend on the mixing intensity. The use of seawater led to a reduction in the size of aggregates. It is suggested that this is a result of polymer coiling, which leads to a decreased ability to form polymeric bridges and thus less particle capture. The fractal dimension of aggregates shows that while the shear rate increases, the aggregates are less compact, with structures possibly more open and further away from a solid spherical body. The greatest reduction occurred in industrial water, related to the larger size of the structures in a low salinity environment.
KW - Floc size distribution
KW - Fractal dimension
KW - Mixing intensity
KW - Seawater
KW - Tailing flocculation
UR - http://www.scopus.com/inward/record.url?scp=85120352441&partnerID=8YFLogxK
U2 - 10.1016/j.mineng.2021.107313
DO - 10.1016/j.mineng.2021.107313
M3 - Article
AN - SCOPUS:85120352441
VL - 176
JO - Minerals Engineering
JF - Minerals Engineering
SN - 0892-6875
M1 - 107313
ER -