Apparatus and process for the gas flotation purification of oil-contaminated water

DETAILED DESCRIPTION The improved gas flotation apparatus of the invention is comprised of an elongate vessel containing a horizontal series of gas flotation cells which are separated by partition walls which have openings to permit substantially horizontal flow of liquid passing from one cell to the next.
The horizontal cells each contain a screen and two gas eductors, one located on each side of the screen.
The screen serves to improve contact between the gas bubbles being emitted from the eductors and the contaminants which are suspended in the liquid being treated.
The location of the openings may be on alternate sides of the vessel in adjacent partition walls to extend the path of liquid flow through the flotation apparatus.
Alternatively, the partition wall openings may all be on the same side of the vessel and the screens may have cutouts on the edges which are on the side which is opposite to the side on which the partition wal cutouts are located.
The tops of the cells are closed off by baffling which inclines in a slightly upward direction from the sidewall to an overflow weir, the baffling serving to direct contaminant-containing froth to the weir for removal of the contaminants from the flotation cells.