Waste-water treatment Microflotation

In contrast, most of the conventional foam separation techniques use large bubbles, requiring relatively high gas flow rates to generate sufficient interfacial area for adhesion of solid particles to bubbles. This causes turbulence at the foam/liquid boundary and, in order to prevent redispersion of floated particles, a rather tall foam column is required (ref. 36). 

As summarized by Cassell et al. (ref. 36), the early work on microflotation described the removal of bacteria and algae from water (ref. 61, 62) thereafter, further studies demonstrated that B. cereus (ref. 63), colloidal constituents of tea (ref. 64), humic acid (ref. 65), colloidal silica (ref. 66), illite (ref. 67), titanium dioxide (ref. 68), and polystyrene latex (ref. 69) could be rapidly and efficiently removed from water by microflotation. The general variety of dispersed materials which have been separated successfully 

Many processes of oceanographic and biological significance have been attributed to the presence of bubbles in the near-surface region of the ocean. For example, Johnson and Cooke (ref. 33) point out that the role of bubbles has been described in such 

During the past 40 years, meteorologists and environment specialists have become increasingly aware of the importance of natural sea bubble processes. Their importance to meteorology stems in part from the fact that surface-active organic material in the sea, mainly biological surfactants, tends to concentrate at the surface (ref. 85). 

In the past three decades, it has become clear that a rather large amount of surface-active organic material ends up in each tiny droplet ejected into the air by bursting bubbles. Some of these materials may reach concentrations in (or on) the droplets well over a thousand times their bulk concentrations in sea water (ref. 46,85,92). The water in the droplets that remain airborne eventually evaporates, leaving the nonvolatile materials to float around in the atmosphere (ref. 46) and ultimately settle out and, as a result, contribute appreciably to soil nutrients (ref. 93-95). 

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