Flotation method is majorly availed in two sectors: mining industry (for separation of metal ores) and in wastewater treatment process (both for municipal and industrial wastewaters) for separation of suspended solids, emulsions, chemical sludge or excess sludge. Traditional flotation relies on floating of solids (mainly suspended solids) on the top of the liquid by air bubbles (in conventional process they have and average diameter of 100–300 μm). Better separation effect is obtained when air bubbles are very small (micro and nano). Special dispersing pumps are able to create air–water mixture of nanobubbles and process is termed as micro- and nanoflotation
2. • Flotation method is majorly availed in two sectors: mining
industry (for separation of metal ores) and in wastewater
treatment process (both for municipal and industrial
wastewaters) for separation of suspended solids,
emulsions, chemical sludge or excess sludge. Traditional
flotation relies on floating of solids (mainly suspended
solids) on the top of the liquid by air bubbles (in
conventional process they have and average diameter of
100–300 μm). Better separation effect is obtained when air
bubbles are very small (micro and nano). Special dispersing
pumps are able to create air–water mixture of nanobubbles
and process is termed as micro- and nanoflotation.
3. • INTRODUCTION
• Coagulants and flocculants are availed in the
process for better agglomeration of small
particles and colloids. Ferrous or aluminum
sulfates are the major common coagulants and
they are generally mixed with water or
wastewater before entering flotation unit.
Nanoflotation is an emerging technology which
uses certain sophisticated techniques and it has
broad spectrum of application.
4. • The oil and gas industry is working to minimize
water use – but water is critical to the
extraction of resources. The industry currently
avails treatment processes that filter water
through membranes and use high levels of
chemicals and energy to produce filtered,
clean effluent water. Nanoflotation technology
could change that.
5. • NANOFLOTATION OVERVIEW
• Description of the Technology
• The nanoflotation technology is an innovative approach to regulate the nano-environment around
colloidal solids. Most colloidal solids will not readily separate from water because of the electric
double layer (EDL) around colloids. The EDL causes the colloids to remain in suspension, repelling
each other. Nanoflotation technology changes the environment around a colloidal solid for a very
short time period causing the EDL to collapse. Solids for this moment in time separate from the
fluid medium and attach
• to other solids or mediums because of van der Waal forces which overcome the diminished
repulsive forces of the EDL. This concept has been attempted in the past by changing the quality of
the water in which the solids are exposed (Mishra et al., 2015) [1]. A typical method to cause the
EDL to collapse is to add NaCl to water. The major problem, with this approach is that water quality
becomes an issue that needs to be managed. The DBE nanoflotation technology does not change
the quality of the water to separate the solids. This technology improves treatment of a wide
variation of suspended solids, colloidal solids and nanoparticle concentrations. In addition, it
garners good reductions in scaling parameters like silica, barium, calcium, magnesium and
manganese, as well as organic reduction in wastewater sourced from industrial or municipal
applications. At the present time the technology has been applied to two very common methods of
water treatment; flotation treatment and low-pressure membrane treatment.
6. • APPLICATION OF NANOFLOTAION
• The application of the nanoflotation technology is through the use
of a surfactant and a “patent pending” high intensity mixing system.
The high intensity mixing is caused by the froth produced from the
use of the surfactant. The fluid containing the solids passes through
a high intensity mixing zone which is also an ionically charged
typically concentrated zone due to the surfactant that has attached
to the air bubbles in the froth. This ionically charged environment
causes the collapse of the EDL and the solids attach to the bubble in
the froth where they float to the surface of a flotation chamber.
Both the froth mixing technology and the use of the high ionically
charged environment have been piloted and displayed with
exceptional success on very difficult waters such as oil sands tailing
pond waters, cooling water, landfill leachate, and refinery oily
process waters
7. REFERNCE
• Features of Nanoflotation Technique – A
Review
• S. Sreeremya International Journal of
Industrial Biotechnology and Biomaterials
Vol. 4: Issue 1