Evaluation of the role of the combination of bulk micro bubbles and Nano bubbles in quartz flotation

Author(s): Daniel Cooper, Luis Paulo

Bulk micro-Nano bubbles have been shown to be effective in restoring flotation and
accelerating the reaction of fine-grained minerals. However, there are currently no
reports on the correlation between BMNB characteristics and flotation performance. For
this purpose, the preparation time (0, 1, 2, 3, 5, and 7 minutes), the aeration rate and the
aging time varied minutes). Micro bubbles and nanobubbles were characterized using
focused beam reflection measurements (FBRM) and nanoparticle tracking analysis
(NTA), respectively. Microfloation of quartz particles was performed using XFG cells in
the presence and absence of BMNB using cetyltrimethylammonium bromide (CTAB) as
a collector. Cell size characterization revealed that the diameters of bulk micro bubbles
(BMB) and bulk nanobubbles (BNB) range from 1 to 10 μm and 50 to 400 nm, respectively.
We have found that manufacturing parameters and aging time have a significant effect on
the number of bubbles generated. When BNB and BMB coexisted, the recovery rate of fine
quartz particles was significantly improved (about 7%), but when only BNB was present,
the promotion of flotation recovery was not significant (2%)... This was primarily related
to the bridging of aggregates and was an advantage of quartz flotation. By comparison,
no aggregates were detected when only nanobubbles were present in the bulk solution.