Device and method for drying pourable products

• US 6,449,869 B1
• Filed: 05/24/2000
• Issued: 09/17/2002
• Est. Priority Date: 09/24/1998
• Status: Expired due to Term

• Current Assignee: CPS Orosel LLC
• Original Assignee: Glatt Systemtechnik Dresden GmbH, KWS SAAT AG
• Inventors: Brückner, Jürgen, Peter, Bruno, Bretschneider, Frank
• Primary Examiner(s): Lu, Jiping
• Application Number:
  US09/554,102
• Time in Patent Office: 846 Days
• Field of Search: 34/58, 34/59, 341/66, 341/68, 341/73, 341/74, 366/286, 366/305, 366/307, 366/314
• US Class Current: 34/59
• CPC Class Codes: A01C 1/06 Coating or dressing seed
• CPC Class Codes: A23P 10/22 Agglomeration or granulation with pulverisation of solid particles, e.g. in a free-falling curtain
• CPC Class Codes: A23P 10/28 Tabletting; Making food bars by compression of a dry powdered mixture
• CPC Class Codes: B01F 27/1154 the discs being cup shaped, e.g. semi sphere
• CPC Class Codes: B01F 27/808 with stirrers driven from the bottom of the receptacle
• CPC Class Codes: B01F 27/93 with rotary discs
• CPC Class Codes: B01F 29/82 the receptacle comprising a rotary part, e.g. the bottom, and a stationary part, e.g. the wall, with optional use of a stirrer; the receptacle comprising parts moving in opposite directions
• CPC Class Codes: B01F 35/71 Feed mechanisms with proportioning B01F35/80
• CPC Class Codes: B01F 35/712 for feeding fluids
• CPC Class Codes: B01F 35/7178 using shovels or scoops
• CPC Class Codes: B01F 35/7179 using sprayers, nozzles or jets
• CPC Class Codes: B01F 35/71805 using valves, gates, orifices or openings
• CPC Class Codes: B01F 35/7547 using valves, gates, orifices or openings
• CPC Class Codes: B01J 2/10 in stationary drums or troughs, provided with kneading or mixing appliances

Abstract

Device and method for drying a pourable products. The device includes a rotor chamber in which a rotor is arranged with a vertical rotor axis. The rotor has a central horizontal surface and, at least in its radially outer third, a conical shell which is inclined to the axis of rotation by 20° to 70°, in such a way that the end face of the conical shell has the largest diameter and is located at the top. The conical shell has, at least partially, sheet-like gas passages in the form of perforations or screens. The method for drying pourable products provides for dry gas to be fed in a sheet like manner to the products to be dried during the radially peripheral circulation of the products without the products being swirled up and being exposed to unacceptable compressive, concussive and/or frictional loads.

Claims

1. A device for drying pourable products comprising a rotor chamber (1), a rotor (4) defining a vertical rotor axis (3) mounted within said rotor chamber, said rotor (4) having a central horizontal surface and, at least in its radially outer third, the shape of a conical shell (22) with an outward and upward inclination to the rotor axis (3) of between 20°

to 70°

, such that an end face of the conical shell (22) lies vertically above the central horizontal surface, said conical shell (22) having, at least partially, drying gas passages in the form of perforations or screens, wherein said rotor chamber (1) includes an axially extending cylindrical wall (6), a plurality of guide vanes ( 11) being affixed statically on said wall and above said rotor (4), said guide vanes (11), in cross section to the rotor axis (3), having substantially the shape of a segment of a circle or spiral, the outer ends of said guide vanes emerging tangentially from the wall (6) of the rotor chamber (1) in the direction of rotation of the rotor (4), the tangents of the wall (6) and the guide vanes (11), at the point where the guide vanes emerge from the wall (6), having substantially the same inclination, said guide vanes having inner ends which lie approximately above the middle part of the rotor radius such that the circulating product, which leaves the rotor (4) under the influence of kinetic energy, rolls on an inside surface of the guide vanes (11) and falls back onto the rotor (4).

2. The device as claimed in claim 1, wherein the guide vanes (11) include adjusting means for adjusting the shape of the segments of the circle or spiral.

3. A device for drying pourable product by subjecting the pourable product to drying gas flow and circulation by a rotor comprising a rotor chamber (1), a rotor (4) defining a vertical rotor axis (3) mounted within said rotor chamber, said rotor (4) having a central horizontal surface and, at least in its radially outer third, the shape of a conical shell (22) with an outward and upward inclination to the rotor axis (3) of between 20°

to 70°

, such that an end face of the conical shell (22) lies vertically above the central horizontal surface, said conical shell (22) having, at least partially, drying gas passages in the form of perforations or screens for receiving gas for drying the product, wherein said rotor chamber (1) includes a wall extending above said rotor and a plurality of guide vanes (11) being affixed statically on said wall and above said rotor (4), and means for circulating the pourable product so that it leaves the rotor (4) under the influence of kinetic energy rolls on the guide vanes and falls back onto the rotor (4) wherein the pourable product is dried by the gas and circulation by the rotor.

4. The device as claimed in claim 3, wherein the rotor (4) is arranged to be exchangeable within said rotor chamber (1).

5. The device as claimed in claim 4, wherein the perforations or screens have different hole diameters or different screen fabrics.

6. A method for using a device as claimed in claim 3 including the step of admitting a drying gas through the perforations or screens for drying said pourable products.