Patent attributes
A separation system is disclosed for separating selected particles from a mixture of particles in a fluid. The system includes a froth flotation vessel 10 into which in use the mixture of particles and fluid are subjected to an upward flow of an introduced gas to form a froth layer 13 which rises above an interface 14 formed between the froth layer 13 and the mixture of particles and fluid 12, such that a quantity of the selected particles is conveyed out of the vessel 10 by the froth layer 13 to become a first product of the system. The vessel 10 also has a first outlet 29 arranged in use for receiving a flow of some of the mixture of particles and fluid from the vessel 10, an entry to the first outlet 29 being located in a region proximate to, but below, the interface 14. The vessel also has a second outlet 20 arranged in use for receiving a flow of some of the mixture of particles and fluid from a region of the vessel 10 which is located below the first outlet 29. In use the first outlet 29 receives a quantity of the selected particles which were not conveyed out of the vessel by the froth layer 13, and the second outlet 20 receives a quantity of the selected particles in a first by-product of the system. The first by-product comprises a relatively higher percentage of solids compared to the flow of particles and fluid in the first outlet 29. The flow of the mixture of particles and fluid from the vessel 10 via the first outlet 29 passes to a classification device 31, 76 which separates the flow into two or more fractions on the basis of their size or density or a combination of the two.
