Froth Flotation : Froth Flotation Varuni Rastogi
Grade Vll Froth Flotation-Definition : Froth Flotation-Definition Froth flotation is a process used for separating hydrophobic [having little or no affinity for water] materials from hydrophilic[having a strong affinity for water].
This is used in several industries . Froth flotation application Industries : Froth flotation application Industries Mining-the froth flotation process is used for the extraction of gold from gold ore, separation of sulfides , carbonates and oxides. Coal and phosphates are also upgraded by flotation technique. Slide 4: Waste water treatment-the flotation process is widely used in industrial waste water plants, where it removes fats, oil, grease, and suspended solids from waste water. Examples in Oil refineries, chemical plants Slide 5: Paper recycling-froth flotation process is used to recover recycled paper. In paper industries this step is called de-inking or just flotation. The target is to release and remove the hydrophobic contaminants from the recycled paper. Principle Of Operation : Principle Of Operation Froth flotation starts by crushing and grinding, of the ore for processing and break the rocks into the wanted mineral and the useless material ,this is known as liberation. The ore is ground into a fine powder and mixed with water and oil .The desired mineral is made hydrophobic by the addition of a collector chemical. As an example, pine oil is used to extract copper. Froth Flotation Process : Froth Flotation Process Science Of Flotation : Science Of Flotation The wetting activity of a surfactant on a particle measured by the contact angle . For complete wetting the contact angle is zero.
The surfactant hold the weight of the heavy particle and floating of the bubbles lift it. Flotation equipment : Flotation equipment Mechanics of flotation : Mechanics of flotation The following steps are followed:-
Grinding to free the mineral particles
Reagent processing to get hydrophobic surface charges on the desired particles
Collection and upward movement by bubbles contact with air or nitrogen
Formation of a stable froth on the surface of the flotation cell
Separation of mineral froth from (flotation cell) Chemicals of flotation : Chemicals of flotation Collectors- increase the natural hydrophobicity of the surface,[collectors e.g. Xanthates, Dithiophosphate etc.] example coal flotation.
Frothers- Pine oil, Alcohols
Modifiers- lime ,acid ,calcium ,sulphur etc. THANK YOU : THANK YOU