Role of Mixing Energy in the Flocculation of Mature Fine Tailings

Autor: Randy J. Mikula, Alebachew Demoz
Rok vydání: 2012
Předmět:
Zdroj: Journal of Environmental Engineering. 138:129-136
ISSN: 1943-7870
0733-9372
DOI: 10.1061/(asce)ee.1943-7870.0000457
Popis: High-molecular-weight polymer flocculants are used for accelerated dewatering of mature fine tailings (MFTs) to reclaim the land occupied by containment ponds. Two anionic polymers were used to flocculate an MFT sample containing 98% by weight of fines smaller than 44 μm in diameter, with 85% of this fraction being clay minerals. The polymer solutions and polymer-treated MFT followed the Herschel-Bulkley and Bingham equations of state, respectively. The coupling of shear thinning and structural breakdown of the flocculated MFT gave rise to cavern formation during mixing. The mixing energy input for a series of MFT flocculation tests, in which other conditions were held constant, was proportional to the mixing time. The mixing tools used for the flocculation process were a Rushton turbine (RT), a pitched-blade turbine (PBT), a vane, and hydrofoil impellers. The flocculation outcome was evaluated on the basis of the amount of water released and the capillary suction test time (CST). The CST of the treated M...
Databáze: OpenAIRE