Fluidized bed for continuous separation of two mixed solid phases

Claim 1

A fluidized closed bed apparatus for the separation of two mixed solid phases, one of said phases being formed by a fluidized powdery material, the other of said phase being formed by a material which is not fluidized under conditions of fluidization of said one phase, said apparatus comprising: a closed casing suspended by resilient means, said casing having a lower casing portion for a flow of a fluidizing gas and an upper casing portion for a flow of fluidized powdery materials; a substantially horizontal porous fluidization wall separating said upper and lower casing portions, said fluidization wall forming an angle of less than 3° with the horizontal; means for said feeding fluidizing gas to said lower casing portion; means for discharging said fluidizing gas from the top of said upper casing portion; means for introducing a mixture of said two phases into said upper casing portion; means for communicating to said porous wall a periodic vibration having a first component directed towards one end of said casing and a vertical upwardly directed component of a magnitude such that the resultant of said components forms an angle α of between 20 and 60° with the vertical, said periodic vibration having a frequency of between 750 and 1500 cycles per minute and an amplitude of between 2 and 5 mm, wherein said means for communicating include means for intermittently producing said vibration for a period of time of from 1 to 3 minutes and at a rate of from 2 to 4 times per hour, whereby said one phase is fluidized; overflow means adjacent an end of said casing opposite said one end for discharging said fluidized phase; and means for removing said other phase from adjacent said one end of said casing, said means for removing comprising a partition having an opening at a vertical level of said porous wall.