Pulse combustion fluidizing dryer

Claim 1

An apparatus for fluidizing and drying moist particles, the apparatus comprising: a tank having a floor with an edge and a central area, and a drying space in the tank above the floor; means for directing gas in the drying space from the edge to the central area; means for introducing moist particles into the drying space to form a bed of particles; means for introducing a fluidizing gas at the edge of the floor, wherein such gas flows into the drying space via the directing means and generates rising streams of gas along the floor to fluidize the bed; a discharge for withdrawing dried particles from the drying space through the floor; and means for withdrawing gas from the drying space.

Claim 2

An apparatus for fluidizing and drying moist particles, the apparatus comprising: a tank having a floor with an edge and a central area, and a drying space in the tank above the floor; means for directing gas in the drying space from the edge to the central area; means for introducing moist particles into the drying space to form a bed of particles; means for introducing a fluidizing gas at the edge of the floor, wherein such gas flows into the drying space via the directing means and generates rising streams of gas along the floor to fluidize the bed; a discharge for withdrawing dried particles from the drying space through the floor; and means for withdrawing gas from the drying space.

Claim 20

An apparatus for fluidizing and drying moist particles, the apparatus comprising: a tank having a floor with an edge and a central area, and a drying space in the tank above the floor, the drying space being enclosed above the floor by a side wall and a top of the tank; means for directing gas in the drying space from the edge to the central area; means for introducing moist particles into the drying space from above the directing means to form a bed of particles; means for imparting relative motion between the bed and the directing means; means for introducing a fluidizing gas at the edge of the floor, wherein such gas flows into the drying space toward the central area via the directing means and generates rising streams of gas along the floor to fluidize the bed; a gas outlet at the top of the tank; means for generating a swirl of gas in the drying space above the fluidized bed cocurrent with the relative motion comprising an auxiliary gas inlet through the side wall for introducing gas on a tangent into the drying space, and additionally comprising an upper horizontal plate and a lower horizontal plate, the upper plate being located proximately below the gas outlet, and the lower plate being located proximately above an annular sleeve extending upwardly into the drying space from the floor, the lower plate being in vertical alignment with the upper plate; and means for withdrawing dried particles from the tank.

Claim 21

An apparatus for fluidizing and drying moist particles, the apparatus comprising: a tank having a floor with an edge and a central area, and a drying space in the tank above the floor, the drying space being enclosed above the floor by a side wall and a top of the tank; means for directing gas in the drying space from the edge to the central area; means for introducing moist particles into the drying space from above the directing means to form a bed of particles; means for imparting relative motion between the bed and the directing means; means for introducing a fluidizing gas at the edge of the floor, wherein such gas flows into the drying space toward the central area via the directing means and generates rising streams of gas along the floor to fluidize the bed; a gas outlet at the top of the tank; means for generating a swirl of gas in the drying space above the fluidized bed cocurrent with the relative motion comprising an auxiliary gas inlet through the side wall for introducing gas on a tangent into the drying space, and additionally comprising an upper horizontal plate and a lower horizontal plate, the upper plate being located proximately below the gas outlet, and the lower plate being located proximately above an annular sleeve extending upwardly into the drying space from the floor, the lower plate being in vertical alignment with the upper plate; and means for withdrawing dried particles from the tank.

Claim 34

A method for fluidizing a bed of particles, the method comprising: forming a bed of particles in a drying space having bottom and side boundaries; introducing a fluidizing gas into the drying space from a periphery of the bottom boundary, the fluidizing gas having radial and tangential components of motion when it is introduced; directing a portion of the fluidizing gas from the periphery into a central ara of the drying space to generate rising streams of such gas along the bottom boundary for fluidizing particles in the bed; and fluidizing the bed with a time average uniform exposure of the bed to the fluidizing gas by continuously changing the exposure of particles in the bed to the gas streams.

Claim 35

A method for fluidizing a bed of particles, the method comprising: forming a bed of particles in a drying space having bottom and side boundaries; introducing a fluidizing gas into the drying space from a periphery of the bottom boundary, the fluidizing gas having radial and tangential components of motion when it is introduced; directing a portion of the fluidizing gas from the periphery into a central ara of the drying space to generate rising streams of such gas along the bottom boundary for fluidizing particles in the bed; and fluidizing the bed with a time average uniform exposure of the bed to the fluidizing gas by continuously changing the exposure of particles in the bed to the gas streams.

Claim 43

A method for fluidizing a bed of particles, the method comprising: forming a bed of particles in a drying space having bottom and side boundaries; introducing a fluidizing gas into the drying space from a periphery of the bottom boundary; directing a portion of the fluidizing gas from the periphery into a central area of the drying space to generate rising streams of such gas along the bottom boundary for fluidizing particles in the bed; fluidizing the bed with a time average uniform exposure of the bed to the fluidizing gas by continuously changing the exposure of particles in the bed to the gas streams; generating a swirl of gas in the drying space above the fluidized bed; and withdrawing dried particles from an upper portion of the drying space.

Claim 44

A method for fluidizing a bed of particles, the method comprising: forming a bed of particles in a drying space having bottom and side boundaries; introducing a fluidizing gas into the drying space from a periphery of the bottom boundary; directing a portion of the fluidizing gas from the periphery into a central area of the drying space to generate rising streams of such gas along the bottom boundary for fluidizing particles in the bed; fluidizing the bed with a time average uniform exposure of the bed to the fluidizing gas by continuously changing the exposure of particles in the bed to the gas streams; generating a swirl of gas in the drying space above the fluidized bed; and withdrawing dried particles from an upper portion of the drying space.

Claim 46

A method for fluidizing a bed of particles, the method comprising: introducing moist particles into a drying space to form a bed of particles on a floor; imparting relative motion between the bed of particles and a gas directing means along the floor; and pulsating hot gas and flowing such gas into the drying space from the periphery of the floor and through the gas directing means from its periphery toward a central portion to generate a flow of upwardly and inwardly extending streams of hot gas across the floor which contact particles to fluidize the bed.

Claim 47

A method for fluidizing a bed of particles, the method comprising: introducing moist particles into a drying space to form a bed of particles on a floor; imparting relative motion between the bed of particles and a gas directing means along the floor; and pulsating hot gas and flowing such gas into the drying space from the periphery of the floor and through the gas directing means from its periphery toward a central portion to generate a flow of upwardly and inwardly extending streams of hot gas across the floor which contact particles to fluidize the bed.

Claim 50

An apparatus for fluidizing and drying moist particles comprising: a tank having an upright cylindrical wall integrally formed with a rotatable floor; an annular baffle within the tank concentric with the wall and spaced from the wall and the floor to define a gas manifold between the wall and the baffle which opens under the baffle into a drying space above the floor, the drying space being enclosed above the baffle by a side wall, integrally formed with the baffle, and a top of the tank; an annular upright sleeve through the floor; means to drive the sleeve to rotate the floor; a collar above the floor around the sleeve; a plurality of blades adjacent the floor extending radially from the collar and secured to the baffle, the blades being sloped in the direction of relative motion of the floor; a plurality of rotating stirring arms above the blades and extending radially from a ring fixed to the sleeve above the collar to a location proximate to the baffle, such stirring arms including a plurality of paddles depending below the arm; a radial inlet through the side wall for introducing moist particles into a side periphery of the drying space above the blades to form a bed of particles; a pulse jet engine having an inlet exhaust, and a tailpipe exhaust arranged for supplying pulsating hot gas and sonic energy to the gas manifold, whereby the pulsating hot gas and sonic energy flow from the gas manifold under the baffle and the blades into the drying space to cause the bed of particles to fluidize and dry; an outlet for withdrawing gases in the center of the top; a lower circular horizontal plate proximately above the annular sleeve and vertically aligned with an upper circular horizontal plate proximately below the outlet for gases in the center of the tank top; an auxiliary gas inlet for introducing pulsating hot gases and sonic energy into the drying space on a tangent to the side wall, the auxiliary inlet being supplied by the inlet exhaust of the pulse jet engine, whereby pulsating hot gas and sonic energy enter the drying space through the auxiliary inlet and circulate concurrently with the floor motion to generate a swirl of gas above the fluidized bed between the horizontal plates; means for adjustably diverting the flow of pulsating hot gas and sonic energy, provided by the inlet exhaust, from supplying the auxiliary gas inlet to augmenting the supply to the gas manifold, whereby to adjust the swirl, from a vortex having a strength sufficient for effecting centrifugal separation of moisture and particles entrained in the vortex, to a swirl having substantially no strength, the flow of gas into the drying space effecting a negative pressure gradient from the fluidized bed to the top of the tank, whereby gas containing moisture follows the gradient and is withdrawn through the gas outlet in the center of the tank top, and gas containing entrained particles follows the gradient and is withdrawn through an outlet offset from the gas outlet; and means for recycling withdrawn gas to the tailpipe end of the pulse jet engine.

Claim 51

An apparatus for fluidizing and drying moist particles comprising: a tank having an upright cylindrical wall integrally formed with a rotatable floor; an annular baffle within the tank concentric with the wall and spaced from the wall and the floor to define a gas manifold between the wall and the baffle which opens under the baffle into a drying space above the floor, the drying space being enclosed above the baffle by a side wall, integrally formed with the baffle, and a top of the tank; an annular upright sleeve through the floor; means to drive the sleeve to rotate the floor; a collar above the floor around the sleeve; a plurality of blades adjacent the floor extending radially from the collar and secured to the baffle, the blades being sloped in the direction of relative motion of the floor; a plurality of rotating stirring arms above the blades and extending radially from a ring fixed to the sleeve above the collar to a location proximate to the baffle, such stirring arms including a plurality of paddles depending below the arm; a radial inlet through the side wall for introducing moist particles into a side periphery of the drying space above the blades to form a bed of particles; a pulse jet engine having an inlet exhaust, and a tailpipe exhaust arranged for supplying pulsating hot gas and sonic energy to the gas manifold, whereby the pulsating hot gas and sonic energy flow from the gas manifold under the baffle and the blades into the drying space to cause the bed of particles to fluidize and dry; an outlet for withdrawing gases in the center of the top; a lower circular horizontal plate proximately above the annular sleeve and vertically aligned with an upper circular horizontal plate proximately below the outlet for gases in the center of the tank top; an auxiliary gas inlet for introducing pulsating hot gases and sonic energy into the drying space on a tangent to the side wall, the auxiliary inlet being supplied by the inlet exhaust of the pulse jet engine, whereby pulsating hot gas and sonic energy enter the drying space through the auxiliary inlet and circulate concurrently with the floor motion to generate a swirl of gas above the fluidized bed between the horizontal plates; means for adjustably diverting the flow of pulsating hot gas and sonic energy, provided by the inlet exhaust, from supplying the auxiliary gas inlet to augmenting the supply to the gas manifold, whereby to adjust the swirl, from a vortex having a strength sufficient for effecting centrifugal separation of moisture and particles entrained in the vortex, to a swirl having substantially no strength, the flow of gas into the drying space effecting a negative pressure gradient from the fluidized bed to the top of the tank, whereby gas containing moisture follows the gradient and is withdrawn through the gas outlet in the center of the tank top, and gas containing entrained particles follows the gradient and is withdrawn through an outlet offset from the gas outlet; and means for recycling withdrawn gas to the tailpipe end of the pulse jet engine.

Claim 53

An apparatus for fluidizing and drying moist particles comprising a tank having a floor and an enclosed drying space; means for introducing moist particles into the drying space to form a bed of particles; means for flowing hot gas into the drying space from the edge of the floor to contact particles and fluidize the bed; means for introducing hot gas tangentially into the drying space to cause gas to swirl above an annular upright sleeve extending into the interior of the tank from the center of the floor, the swirling gas for removing moisture from particles entrained therein, the upright sleeve dividing the drying space into a fluidized bed region below a swirl region and comprising an overflow drain for the fluidized bed; and means for withdrawing gases from the drying space.

Claim 54

An apparatus for fluidizing and drying moist particles comprising a tank having a floor and an enclosed drying space; means for introducing moist particles into the drying space to form a bed of particles; means for flowing hot gas into the drying space from the edge of the floor to contact particles and fluidize the bed; means for introducing hot gas tangentially into the drying space to cause gas to swirl above an annular upright sleeve extending into the interior of the tank from the center of the floor, the swirling gas for removing moisture from particles entrained therein, the upright sleeve dividing the drying space into a fluidized bed region below a swirl region and comprising an overflow drain for the fluidized bed; and means for withdrawing gases from the drying space.

Claim 55

An apparatus for fluidizing and drying moist particles, the apparatus comprising: a tank having an upright wall and a floor with an edge and a central area, and a drying space in the tank above the floor; an upright annular sleeve extending into the drying space through the center of the floor; a baffle around the edge of the floor spaced from the wall and the floor to define a gas manifold between the wall and the baffle in communication under the baffle with the drying space; a plurality of blades adjacent the floor, the blades being located about the sleeve and extending to the baffle; means for imparting relative motion between the floor and the blades; means for introducing moist particles into the drying space above the blades to form a bed of particles; means for supplying a fluidizing gas to the gas manifold, whereby the fluidizing gas flows from the gas manifold under the baffle and the blades into the drying space to cause the bed of particles to fluidize and dry, the blades being sloped in the direction of relative motion to provide a leading edge and a raised trailing edge located further above the floor than is the leading edge, the leading edge being sufficiently close to the floor for sweeping particles off the floor and shearing the bed along the top of the blades over the trailing edge, the trailing edge directing the hot gas into the drying space cocurrently with the relative motion; a gas outlet in the tank for withdrawing gases; and means for withdrawing dried particles from the tank.

Claim 56

An apparatus for fluidizing and drying moist particles, the apparatus comprising: a tank having an upright wall and a floor with an edge and a central area, and a drying space in the tank above the floor; an upright annular sleeve extending into the drying space through the center of the floor; a baffle around the edge of the floor spaced from the wall and the floor to define a gas manifold between the wall and the baffle in communication under the baffle with the drying space; a plurality of blades adjacent the floor, the blades being located about the sleeve and extending to the baffle; means for imparting relative motion between the floor and the blades; means for introducing moist particles into the drying space above the blades to form a bed of particles; means for supplying a fluidizing gas to the gas manifold, whereby the fluidizing gas flows from the gas manifold under the baffle and the blades into the drying space to cause the bed of particles to fluidize and dry, the blades being sloped in the direction of relative motion to provide a leading edge and a raised trailing edge located further above the floor than is the leading edge, the leading edge being sufficiently close to the floor for sweeping particles off the floor and shearing the bed along the top of the blades over the trailing edge, the trailing edge directing the hot gas into the drying space cocurrently with the relative motion; a gas outlet in the tank for withdrawing gases; and means for withdrawing dried particles from the tank.