Principle of operation. This slurry (more properly called the pulp) of hydrophobic particles and hydrophilic particles is then introduced to tanks known as flotation cells that are aerated to produce bubbles. The hydrophobic particles attach to the air bubbles, which rise to the surface, forming a froth.
factors which influence performance of flotation cells based on the experience of some of the units. Quality of Coal Coals from shallow depths, open cast, oxidized coals and from long held stocks at Pit Head, the yield drops. Oxidation dilutes the hydrophobic selectivity of coals. The nature of minerals also make some impact.
Xanthate Application in Copper Froth Flotation In the flotation process of copper ore, xanthate mainly reacts with Cu2+. Therefore, when processing minerals containing more Cu2+ on the surface, the effect of xanthate is stronger, and the order of its action is: Cu2S > CuS > Cu5FeS4 > CuFeS2.
Froth flotation Optimization of flotation separation using interfacial chemical methods. Flotation has become established as an efficient solid liquid separating method in ore processing and for the separation of colored pigments (de inking) in paper recycling.
Flotation can be performed by different types of machines, in rectangular or cylindrical mechanically agitated cells or tanks, columns, a Jameson Flotation Cell or deinking flotation machines. The mechanical cells are based in a large mixer and diffuser mechanism that can be found at the bottom of the mixing tank and introduces air, providing a mixing action.
Particles enter the froth phase when a bubble carrying the particles crosses the pulp froth interface. The froth phase floats on top of the pulp phase and is formed by the bubbles that break through the surface of the pulp phase. The water in the flotation cell is conditioned to promote the formation of a more or less stable froth.
Froth flotation and film (skin) flotation are the best examples of flotation taking place on the gasliquid interface. Film flotation occurs on a free water surface. Particles are gently fed onto the free surface, allowing the separation of hydrophobic (water repelling) particles, which attach to the free surface, from non floatable hydrophilic (water attracting) particles, which sink into the liquid.
For example, if 20% of the water entering a flotation cell is carried into the froth, then up to 20% of the fine particles entering the cell will be entrained. The entrainment of coarser particles will be less than 20%, due to their greater ability to drain from the froth.