Dissolved gas flotation in the industrial wastewater market
Regulatory drivers and technological improvements have spurred
the innovative application of dissolved gas flotation (DGF)
technology in the industrial wastewater market. The technology
relies on contacting wastewater with a sidestream saturated with
gas—traditionally air or nitrogen—at high pressure. As the
sidestream is released into an atmospheric reactor, the gas
comes out of solution and forms microbubbles. The bubbles attach
to solids and oil droplets, increasing their effective buoyancy
and floating them to the surface of the DGF reactor. The
concentrated pollutants are collected from the water surface for
processing and/or disposal. During the past century, DGF
primarily has been used to separate oil and suspended solids
from wastewater; the use of the technology to remove biological
solids, metals and nutrients, however, has grown in the past
decade. DGF, conventional gravity clarification (CGC),
filtration and sorption are conventional tech