MY8000134A - Improvements in or relating to the separation of components from a suspension - Google Patents

Abstract

1490227 Flotation apparatus; dispersing gases in liquids PIELKENROOD-VINITEX BV 6 Dec 1974 [22 Dec 1973] 52771/74 Headings B1C B1D and B2H A method of separating suspended material from a suspension comprises reducing the pressure of a pressurized liquid containing gas or a volatile substance to form a dispersion of gas bubbles in the liquid, and introducing the liquid into a tank containing the suspension and forming part of a plate-type separator 7 so that the bubbles become attached to the suspended material and cause it to float. In the embodiment shown the suspension is introduced to a chamber 3 through a duct 11 and a nozzle 12, the latter consisting of a tube having a longitudinal slot. A pump 16 draws in air through a pipe 18 and liquid through a pipe 17 and produces a pressure in a pipe 14. This pressure is suddenly relieved beyond a valve 15 to produce a dispersion of air bubbles in the liquid which is injected into the chamber 3 through a nozzle 13. Floating material passes over a weir 5 into a discharge chamber 6 and sediment is collected in a hopper 10 after passing through an assembly 7 of superposed parallel corrugated plates. In another embodiment, Fig. 3 (not shown) there are separate pumps (16) and (21) for the liquid and air which may be stored under pressure in a mixing vessel (22) before passing through the valve 15. The suspension to be treated and the dispersion of gas bubbles in the liquid may be introduced into the chamber 3 through the same nozzle, and in another modification the suspension itself is pressurized and mixed with air to form the dispersion of gas bubbles. The suspension may be subjected to a coalescence treatment in a device located either inside or outside the chamber 3.