Patent US3901645A successfully refreshed from Google Patents.
US3901645A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Calcining kettle and system
Assignee: Universal Kettle Co Inc
•
Filing: 1971-04-07
•
Granted: 1975-08-26
•
Expires: 1991-04-07
Abstract
Abstract A calcining kettle is provided with an improved heating system involving the use of flat flame burners for heating the bottom wall of the kettle and a luminous wall furnace for heating the side wall of the kettle with heat during the calcining operation. A space between the luminous wall furnace and the kettle provides an exhaust passage for combustion gases. This exhaust passage extends across the top wall of the kettle for blocking heat loss therethrough. An improved agitator is also provided which has scraper elements moving in close association with the area of the kettle bottom wall and scraper elements extending outwardly therefrom for riding in scraping relationship with the kettle bottom corner. The kettle side wall is provided with rises and depressions, such as corrugations, to increase its surface area for maximizing heat transfer from the luminous wall furnace to the materials being calcined within the kettle. The agitator includes a plurality of three rotary driven shafts aligned with their axes in a common plane. Each shaft carries impeller blades which extend to adjacent at least one of the other shafts and are axially staggered with respect to the blades thereof and is driven in a direction of rotation opposite to that of the next adjacent shaft. The kettle includes a dust separation system for conjointly recovering dust from the feed material and steam from the kettle. The operating system also includes conduits for delivering combustion gases from the kettle heaters through a hammer mill for fluidizing comminuted feed and carrying the feed overhead for dust separation. The feed is delivered to the kettle via a surge bin which can be operated to provide batch by batch operation or continuous operation. The product can be cooled by countercurrent or cocurrent heat exchange flow with water and dust separated from the product can be collected along with the feed, dust and steam. A method of operating the system is also provided.
Inventors
- 👤 George E Rowland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:51
CPC Classifications
F; F27; F27B; F27B15/00; C; C04; C04B; C04B11/00; C04B11/02; C04B11/028; C04B11/0281
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
120 words
A device for calcining particulate material comprising a kettle having a side wall and a bottom wall, means for agitating the particulate material in the kettle, flat flame burner means for heating the bottom wall, and a luminous wall furnace surrounding and facing the side wall for heating the side wall with radiant heat, said luminous wall furnace including a porous material having a firing surface facing said side wall at which combustion takes place to generate principally radiant energy to be directed toward said side wall and a manifold on the side of said surface opposite said side wall for receiving an air-gas mixture and applying the mixture to said porous material for flow therethrough to said firing surface.
Claim 2
Independent Claim
120 words
A device for calcining particulate material comprising a kettle having a side wall and a bottom wall, means for agitating the particulate material in the kettle, flat flame burner means for heating the bottom wall, and a luminous wall furnace surrounding and facing the side wall for heating the side wall with radiant heat, said luminous wall furnace including a porous material having a firing surface facing said side wall at which combustion takes place to generate principally radiant energy to be directed toward said side wall and a manifold on the side of said surface opposite said side wall for receiving an air-gas mixture and applying the mixture to said porous material for flow therethrough to said firing surface.
Claim 3
Dependent Claim
35 words
The device of claim 1 wherein said luminous wall furnace is spaced from the side wall forming an exhaust passage between the furnace and the side wall for combustion gases from the flat flame burner.
Claim 4
Dependent Claim
37 words
The device of claim 2 in which said kettle has a top wall and including means defining a heat exchange chamber in heat transmitting association with the top wall for receiving combustion gases from said exhaust passage.
Claim 5
Dependent Claim
38 words
The device of claim 1 wherein the bottom wall is convex and said agitating means includes scraper means driven in scraping association with the bottom wall and at the juncture of the bottom wall with the side wall.
Claim 6
Dependent Claim
17 words
The device of claim 1 wherein said side wall contains rises and depressions increasing its surface area.
Claim 7
Dependent Claim
11 words
The device of claim 5 wherein said side wall is corrugated.
Claim 8
Dependent Claim
110 words
In a calcining kettle having a side wall, a convex bottom wall, and a discharge port at about the juncture of the bottom and side walls, agitator means comprising blade means having a lower surface spaced from but generally conforming to the surface of the kettle bottom wall, said blade means having upturned elements at the ends thereof spaced from the side wall, first scraper means extending from the bottom of the blade means in close scraping association with the kettle bottom wall, and second scraper means at each end of the blade means extending approximately from the upturned elements outward toward the juncture of the bottom and side walls.
Claim 9
Dependent Claim
110 words
In a calcining kettle having a side wall, a convex bottom wall, and a discharge port at about the juncture of the bottom and side walls, agitator means comprising blade means having a lower surface spaced from but generally conforming to the surface of the kettle bottom wall, said blade means having upturned elements at the ends thereof spaced from the side wall, first scraper means extending from the bottom of the blade means in close scraping association with the kettle bottom wall, and second scraper means at each end of the blade means extending approximately from the upturned elements outward toward the juncture of the bottom and side walls.
Claim 10
Independent Claim
80 words
A device for calcining particulate material comprising a kettle, means for heating the kettle and agitator means for agitating particulate material in the kettle during heating, said agitator means comprising a plurality of at least three driven shafts mounted for rotation through the top wall, and blade means on each shaft extending to adjacent at least one of the other shafts and axially staggered with respect to the blade means on the other shaft and overlapping the blade means thereon.
Claim 11
Independent Claim
80 words
A device for calcining particulate material comprising a kettle, means for heating the kettle and agitator means for agitating particulate material in the kettle during heating, said agitator means comprising a plurality of at least three driven shafts mounted for rotation through the top wall, and blade means on each shaft extending to adjacent at least one of the other shafts and axially staggered with respect to the blade means on the other shaft and overlapping the blade means thereon.
Claim 12
Dependent Claim
42 words
The device of claim 8 including a stabilizer bar extending across the kettle adjacent the lower ends of the shafts, and means mounting the shafts on the stabilizer bar for rotation relative thereto whereby the shafts are prevented from Bending during rotation.
Claim 13
Dependent Claim
23 words
The device of claim 9 wherein said shafts have approximately coplanar axes and said stabilizer bar is a straight bar intersecting said axes.
Claim 14
Dependent Claim
28 words
The device of claim 8 including variable speed drive means for driving each shaft in an opposite direction of rotation from that of the shaft next adjacent thereto.
Claim 15
Dependent Claim
32 words
The device of claim 8 wherein the blade means on each shaft are disposed for delivering air in a downward direction for fluidizing the particulate material at the bottom of the kettle.
Claim 16
Dependent Claim
73 words
A calcining system for calcining particulate material comprising a calcining kettle, means for heating said kettle, means for separating dust from the particulate material to be calcined, means for delivering the particulate material from the dust separation means to the kettle, means for recovering product calcined material from the kettle, means for recovering vapors or steam from the kettle, and means for combining the steam and separated dust and for collecting the same.
Claim 17
Dependent Claim
73 words
A calcining system for calcining particulate material comprising a calcining kettle, means for heating said kettle, means for separating dust from the particulate material to be calcined, means for delivering the particulate material from the dust separation means to the kettle, means for recovering product calcined material from the kettle, means for recovering vapors or steam from the kettle, and means for combining the steam and separated dust and for collecting the same.
Claim 18
Dependent Claim
24 words
The system of claim 13 including means for separating dust from the product and for combining it with the steam and other separated dust.
Claim 19
Dependent Claim
16 words
The system of claim 13 wherein the heating means comprises burner means for producing combustion gases.
Claim 20
Dependent Claim
59 words
The system of claim 12 including a hammer mill for grinding the material to be calcined, means for directing combustion gases to the haammer mill for fluidizing ground material and delivering it to the dust separating means and for delivering the dust from the dust separating means into combination with the steam and thence to the dust collecting means.
Claim 21
Dependent Claim
42 words
The system of claim 16 wherein the means for separating dust is a cyclone and including a surge bin for receiving particulate material from the cyclone, and dump gate means for delivering the particulate material from the surge bin to the kettle.
Claim 22
Dependent Claim
14 words
The system of claim 13 including heat exchange means for cooling the calcined product.
Claim 23
Independent Claim
69 words
A method of calcining particulate material which comprises delivering said material to a calcining kettle, heating the material in the kettle, recovering calcined product from the kettle, recovering steam from the kettle, separating dust from said materials, combining the recovered steam and separated dust, collecting the same and further including the step of separating dust from the recovered product and combining with the steam and dust from the feed.
Claim 24
Independent Claim
69 words
A method of calcining particulate material which comprises delivering said material to a calcining kettle, heating the material in the kettle, recovering calcined product from the kettle, recovering steam from the kettle, separating dust from said materials, combining the recovered steam and separated dust, collecting the same and further including the step of separating dust from the recovered product and combining with the steam and dust from the feed.
Claim 25
Independent Claim
74 words
A method of calcining particulate material which comprises delivering said material to a calcining kettle, heating the material in the kettle, recovering calcined product from the kettle, recovering steam from the kettle, separating dust from said materials, combining the recovered steam and separated dust, collecting the same and further including the step of comminuting the feed material and fluidizing it with combustion gases from the heating means for delivery to the dust separating means.
Claim 26
Independent Claim
74 words
A method of calcining particulate material which comprises delivering said material to a calcining kettle, heating the material in the kettle, recovering calcined product from the kettle, recovering steam from the kettle, separating dust from said materials, combining the recovered steam and separated dust, collecting the same and further including the step of comminuting the feed material and fluidizing it with combustion gases from the heating means for delivery to the dust separating means.
Claim 27
Dependent Claim
24 words
The method of claim 19 including the step of passing the product calcined material in heat exchange flow with water for cooling the product.
References Cited (Backward Citations)
US444658A
Cited
US852616A
Cited
US1165815A
Cited
US1547872A
Cited
US1746294A
Cited
US3001780A
Cited
US2982532A
Cited
US3236509A
Cited
US3307840A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |