TY - JOUR 
A1 - Jeldres, Matías
AU - Piceros Fuentes, Eder Cristóbal
AU - Toro Villarroel, Norman Rodrigo
AU - Torres Albornoz, David Antonio
AU - Robles Vásquez, Pedro Adrián
AU - Leiva, Williams H.
AU - Jeldres Valenzuela, Ricardo Iván
T1 - Copper tailing flocculation in seawater: relating the yield stress with fractal aggregates at varied mixing conditions
Y1 - 2019
SN - 2075-4701
UR - http://hdl.handle.net/10317/9273
AB - The implications of physical conditions of the feedwell on the rheological properties of synthetic copper tailings, flocculated in seawater, were analysed. The mixing intensity of flocculation was related to the structural characteristics of the aggregates, and the outcomes were linked to the yield stress of the pulp sediments. Tailings settling assays were conducted by using a 30 mm turbine type stirrer with an in-situ aggregate size characterisation. The structural characteristics of the aggregates were determined by using the focused beam reflectance measurement (FBRM). After a mixing time between the pulp and the flocculant, the sample was allowed to settle for 2.5 h, where the variation of the sediment height was minimal. The sediment was gently removed and subjected to rheological characterisation. The yield stress was measured on an Anton Paar MCR 102 rheometer (ANAMIN Group, Santiago, Chile), with a vane-in-cup configuration. The mixing intensity was related to the characteristics of the aggregates, and the outcomes were linked to the yield stress of the flocculated pulp sediments. More aggressive hydrodynamics deteriorated the structure of the aggregates, promoting the reduction of both its size and the fractal dimension. This brought direct consequences on the rheological properties of the sediments: at higher mixing level, the yield stress was lower. The explanation lies in the structural changes of the aggregates, where at a fixed mixing rate, the yield stress presented a seemingly exponential increase over the fractal dimension. Additionally, correlations were found between the rheological properties with settling rate and aggregate size.
KW - Ciencia de los Materiales e Ingeniería Metalúrgica
KW - Seawater
KW - Copper tailings
KW - Rheology
KW - Fractal aggregates
KW - Thickening
KW - 5102.10 Metalurgia
LA - eng
PB - MDPI
ER -