Fluidized bed apparatus

Abstract

Fluidized bed apparatus, comprising a fluidized bed vessel in which a substantially horizontal rotor disc is arranged above a perforated bottom or above an air chamber for rotary movement about an at least approximately vertical axis and for adjustment along said axis. The fluidized bed vessel is tapered upwardly, one portion inwardly and one outwardly to enhance the flow therein and the rotor disc forms a flat cone and the disc may have a central cone with the rotor disc covering at least the central part of the perforated bottom. The questions raised in reexamination request No. 90/000,329, filed 02/15/83, have been considered and the results thereof are reflected in this reissue patent which constitutes the reexamination certificate required by 35 U.S.C. 307 as provided in 37 CFR 1.570(e).

What is claimed is: 
     
       1. A fluidized bed apparatus comprising.Iadd.:.Iaddend. .[.a fluidized bed vessel.]. .Iadd.in three vertically contiguous sections, an upper section constituting an expansion zone, an intermediate section .Iaddend.having .Iadd.a first .Iaddend..[.walls tapered inwardly as it extends.]. .Iadd.wall extending .Iaddend.upwardly.Iadd., and a lower section including a second wall tapered inwardly frustoconically as it extends downwardly .Iaddend.and .[.having a perforated.]. .Iadd.terminating in a .Iaddend.bottom.[.,.]. .Iadd.inlet for air, or other gas, said intermediate and lower sections constituting a fluidized bed vessel, with said second wall having an interior wall surface, said interior wall surface being divided into an upper portion and a lower portion, said upper portion being defined in the area of vertical movement of a rotor disc, said upper portion widening frustoconically in an upward direction;.Iaddend.   a substantially horizontal rotor disc .Iadd.having a substantially flat bottom and being arranged for vertical movement, said rotor disc .Iaddend.arranged above said bottom .Iadd.inlet .Iaddend.of said vessel.[.,.]. .Iadd.and below the top of said lower section and in radial proximity with said upper portion of said interior wall surface of said lower section;.Iaddend.   said rotor disc being of smaller horizontal dimension than the .[.corresponding.]. horizontal dimension .Iadd.of the top of said lower section .Iaddend.of .Iadd.said interior wall surface of .Iaddend.said vessel .[.and.]. .Iadd.but of larger horizontal dimension than the horizontal dimension of the bottom inlet of said lower section, and said rotor disc .Iaddend.forming an annular gap between the circumferential edge of said rotor disc and .[.the.]. .Iadd.said .Iaddend.upwardly and .[.inwardly tapered.]. .Iadd.outwardly frustoconically widening .Iaddend..[.wall.]. .Iadd.upper portion .Iaddend.of said .Iadd.lower section of said .Iaddend.vessel.[.,.]..Iadd.;.Iaddend.   .Iadd.adjusting .Iaddend.means for adjusting the .Iadd.vertical .Iaddend.height of said rotor disc connected to said rotor disc and thereby changing the width of said annular gap.[.,.]. .Iadd.relative to the upper portion of said lower section from zero gap at the lowest position to a predetermined gap at the highest position of the rotor disc;.Iaddend.   means for rotating said rotor disc about an at least approximately vertical axis connected to said rotor disc.[.,.]..Iadd.;.Iaddend.   .Iadd.sucking .Iaddend.means .Iadd.positioned above and in fluid communication with said upper section .Iaddend.for .[.moving.]. .Iadd.sucking .Iaddend.a flow of air or other gas into said vessel through said bottom .Iadd.inlet .Iaddend.and through said annular gap around the periphery of said rotor disc.[.,.]. .Iadd.so that the flow of air or other gas tends to follow the outwardly widening wall surface of the lower section;.Iaddend.   .Iadd.said adjusting means closing of said annular gap to cause said sucking means to create a pressure differential between the portion of said fluidized vessel on one side of said rotor disc and the remaining portion of said vessel on the other side of said rotor disc when said sucking means is operating;.Iaddend.   means for releasing material to be treated into the .Iadd.fluidized bed vessel above said rotor disc to form .Iaddend..[.moving gas forming.]. a fluidized bed moved by said rotor disc and the .[.moving.]. gas .[.passing.]. .Iadd.being sucked .Iaddend.through said annular gap.[.,.]..Iadd.; and   nozzle means for introducing liquid into said fluidized bed vessel, said nozzle means including a plurality of nozzles disposed in a ring about the periphery of said vessel below said expansion zone;.Iaddend.   whereby the velocity of the flow of gas through said annular gap.[.is.]. .Iadd.may be .Iaddend.adjusted to the varying density, particle size, and surface characteristics of the material to be treated by varying the height of said rotor disc in relation to said .[.walls.]. .Iadd.upper portion of said interior walls .Iaddend.of said vessel to decrease said gap and increase flow velocity and alternatively to increase said gap and decrease flow velocity. .[.   
     
     
       2.  The fluidized bed apparatus as claimed in claim 1, characterized in that the distance between said perforated bottom and said rotor disc is in the range from 0.5 to 20.0 mm..]. .[.3. The fluidized bed apparatus as claimed in claim 2, further characterized by the base area of said rotor disc amounting to from 60 to 80% of the area of   
     
     
        the bottom of said fluidized bed vessel..]. 4. The fluidized bed apparatus as claimed in claim 1, further characterized by said rotor disc being a shallow cone having an angle of inclination not   
     
     
        exceeding 45°. 5. The fluidized bed apparatus as claimed in claim 1, further characterized by said rotor disc having a central cone,   said central cone having a base area diameter amounting to from 15 to 50% of the diameter of said rotor disc and a height amounting to from 5 to 50%   
     
     
        of the diameter of said rotor disc. .[.6.  The fluidized bed apparatus as claimed in claim 5, further characterized by the base area of said rotor disc amounting to from 60 to 80% of the area of the bottom of said fluidized bed vessel..]. .[.7. The fluidized bed apparatus as claimed in claim 1, further characterized by   the base of said rotor disc amounting to from 60 to 80% of the area of the   
     
     
        bottom of said fluidized bed vessel..]. 8. The fluidized bed apparatus as claimed in claim 1, further characterized by attachment means to increase centrifugal and upward flow in the fluidized   
     
     
        bed, attached on the upper side of said rotor disc. 9. The fluidized bed apparatus as claimed in claim 8, further characterized by 
     
     
       said attachment means being baffle plates. 10. The fluidized bed apparatus as claimed in claim 8, further characterized by said attachment means being blades. .[.11. The fluidized bed apparatus as claimed in claim 1, further characterized by   said fluidized bed vessel including two sections disposed one above the other,   the lower of said sections together with said rotor disc defining said annular gap and being more tapered inwardly as it extends upwardly than   
     
     
        the upper of said sections..]. 12. The fluidized bed apparatus as claimed in claim 1, further characterized by said means for adjusting the height of said rotor disc including piston means attached to said rotor disc for vertical reciprocating motion. .[.13. The fluidized bed apparatus as claimed in claim 12, further characterized by   said means for adjusting the height of said rotor disc further including vertically adjustable guide means supporting the underside of said rotor   
     
     
        disc..]. 14. The fluidized bed apparatus as claimed in claim 1, further characterized by .[.said source of air including.]. means to exhaust air from said fluidized bed vessel, .[.and.]. regulating means in the path of air exhausted from said vessel .Iadd.means to draw air into said vessel from the outside and to pass same through said bottom, and means .Iaddend.to regulate the amount of air entering from outside said vessel and passing through said .[.perforated.]. bottom     
     
     
        .[.with said air exhausted from said vessel.].. 15. The fluidized bed apparatus as claimed in claim 1, further characterized by said means for adjusting the height of said rotor disc also being operable during rotation of said rotor disc. .[.16. A fluidized bed apparatus comprising   a fluidized bed vessel,   an annular seat formed in said vessel,   an annular seat formed in said vessel,   a substantially horizontal rotor disc arranged within said vessel,   said rotor disc forming an annular gap between the circumferential edge of said rotor disc and said annular seat,   means for adjusting the height of said rotor disc connected to said rotor disc and thereby changing the width of said annular gap,   means for rotating said rotor disc about an at least approximately vertical axis connected to said rotor disc,   means for moving a flow of air or other gas into said vessel beneath said rotor disc and through said annular gap around the periphery of said rotor disc,   means for releasing material to be treated into said vessel above said rotor disc,   said material forming a fluidized bed moved by said rotor disc and the   
     
     
        moving gas passing through said annular gap..]. 17. The fluidized bed apparatus as claimed in claim .[.16.]. .Iadd.1.Iaddend., wherein said means for adjusting the height of said rotor disc are adapted to move the rotor disc in an abutting engagement with said .[.annular seat.]. .Iadd.upper portion .Iaddend.thus closing said annular gap. .[.18. The fluidized bed apparatus as claimed in claim 16 wherein said vessel has a wall portion tapered inwardly as it extends upwardly, said wall portion surrounding said rotor disc, said annular seat being arranged at said wall portion..]. .[.19. The fluidized bed apparatus as claimed in claim 16, wherein said vessel has a wall portion tapered inwardly as it extends downwardly, said wall portion surrounding said rotor disc, said annular 
     
     
        seat being arranged at said wall portion..]. 20. The fluidized bed apparatus as claimed in .[.claim 18 or.]. claim .[.19.]. .Iadd.1.Iaddend., wherein said rotor disc comprises a sealing means fixed along its circumferential edge. .Iadd.21. The fluidized bed apparatus as claimed in claim 1, further characterized by the means for sucking a flow of air or other gas comprising a fan mounted downstream of the upper section of the fluidized bed vessel to suck air or other gas from said upper section..Iaddend. .Iadd.22. The fluidized bed apparatus as claimed in claim 21, further characterized by   filter means interposed between the fan and the upper section of the fluidized bed..Iaddend. .Iadd.23. The fluidized bed apparatus as claimed in claim 21 wherein the fan exhausts to the outside via a regulating flap and fresh air is sucked into the bottom of said vessel through a regulated inlet..Iaddend. .Iadd.24. The fluidized bed apparatus of claim 1, further comprising regulating means for regulating the volume of air passing through said vessel..Iaddend.