Abstract
It is well known that reverse flotation performance of iron oxides is affected by water quality. Since many potential variations among water sources recycling in a mineral processing plant bring unpredictable effects on the flotation system of iron oxides: disturbing ions/compounds, pH, hardness, residual reagents, etc. In this study, the recycled tailing water from a local plant, characteristically constituting of Ca2+, Mg2+, Na+, K+, Al3+, Fe3+, Cl−, SO42− etc., was introduced into the cationic reverse flotation process of an iron ore. A series of bench flotation tests using iron ores, micro-flotation tests using pure fine quartz, water chemical analyses, and zeta potential measurement were conducted with the objective of identifying the possible influences of both cations and anions in the recycled tailing water on the flotation performance. The flotation results pointed out that the cation with higher valency had more severe influences on the recovery of iron oxides. The formation of the pH-dependent surface complexes on mineral surfaces, for example, Fe(OH)+, Fe(OH)2+, and Fe(OH)3 resulted from Fe3+ ions adsorption, contributed to the less negative zeta potentials of the quartz, and consequently weakened its interaction with the amine collector. It is worthy to note that SO42− ions seem to have a more positive effect on the recovery of iron oxides than Cl− ions. This is probably attributed to the formation of inner/outer- sphere surface complexes on the iron oxides, inhibiting the dissolution of the iron ions/species, and the coordination with these cations from the recycled tailing water, shielding their disturbances in the flotation.
Highlights
It is essential for a mineral processing plant to reduce plant-operating costs and minimize impact on the local ecosystem by increasing water reuse
It seems to be complicated to figure out specific effects of these cations on the effectiveness of flotation since they may be detrimental in some cases [5,11,13], while in other cases they may be beneficial to the flotation process [4,7,8,9,10,12]
As a function of % recycling tailing water reported into the flotation system at a pH range of 8.5–9.3
Summary
It is essential for a mineral processing plant to reduce plant-operating costs and minimize impact on the local ecosystem by increasing water reuse. K+ , Na+ , Ca2+ , Mg2+ , Fe3+ , Al3+ , Cl− , No3 − , SO4 2− etc., possibly occurs during water recycling in a flotation process. This could bring an unexpected change into the physicochemical/electrochemical atmosphere of flotation pulp, affecting mineral floatability as well as dewatering and pumping [3]. Since the promotive effects of these cations mainly occur in the anionic reverse flotation of iron oxides [4,7,8,9,10] while the competitive effects of them obviously take place in the cationic reverse flotation or anionic direct flotation [5,11,13]. Either promotive or Minerals 2019, 9, 161; doi:10.3390/min9030161 www.mdpi.com/journal/minerals
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
