Device to take in fumes and cool the roof of electric furnaces

• US 6,535,543 B2
• Filed: 08/27/2001
• Issued: 03/18/2003
• Est. Priority Date: 08/29/2000
• Status: Expired due to Fees

• Current Assignee: Danieli & C Officine Meccaniche SPA (SIND International SPA)
• Original Assignee: Danieli & C Officine Meccaniche SPA (SIND International SPA)
• Inventors: Poloni, Alfredo, Tischenko, Peter, Della Negra, Angelico, Pavlicevic, Milorad
• Primary Examiner(s): Hoang, Tu Ba
• Application Number:
  US09/938,859
• Publication Number:
  US 20020027939A1
• Time in Patent Office: 568 Days
• Field of Search: 373/2, 373/8, 373/9, 373/71-74, 373/77, 266/158
• US Class Current: 373/73
• CPC Class Codes: F27D 1/1816 Removable covers specially adapted for arc furnaces
• CPC Class Codes: F27D 17/003 of waste gases emanating from an electric arc furnace

Abstract

Device to take in fumes and cool the roof (10) of electric furnaces. The device has a central aperture (11) into which an electrode can be inserted and a peripheral aperture (12) to take in and discharge the fumes. The device also has a first cooling system (13) for a central zone surrounding, and cooperating with, the central aperture (11), and a second system (15) to take in and convey the fumes. The first cooling system (13) includes a circular cyclone chamber (18) having a plurality of turns (19) able to cool the zone surrounding the central aperture (11).

Claims

1. A device to take in fumes and cool a roof (10) of an electric furnace, said furnace comprising at least a central zone surrounding a substantially central aperture (11) into which at least one electrode can be inserted and moved, and a peripheral fume-discharge aperture (12) to take in and discharge the fumes, said device comprising:

at least a first cooling system (13) for intaking a first portion of the fumes, and cooling the central zone surrounding said central aperture (11), and

a second cooling system (15), comprising the peripheral fume-discharge aperture, for intaking, cooling and conveying at least a second portion of the fumes to outside the furnace,

wherein said first cooling system (13) comprises at least a circular cyclone chamber (18) comprising a plurality of turns (19) able to cool the central zone surrounding said central aperture (11) and able to create a cyclonic development of the first portion of the fumes.

2. The device as in claim 1, wherein said turns (19) are arranged on a substantially vertical plane to form a ring around said central aperture (11).

3. The device as in claim 1, wherein said turns (19) consist of pipes (17) wherein cooling fluid circulates.

4. The device as in claim 1, wherein said turns are made of material resistant to high temperatures.

6. The device as in claim 1, wherein a plurality of cooling pipes (117) is arranged on a substantially horizontal plane in cooperation with an inner surface of said cyclone chamber (18) facing towards the at least one electrode.

7. The device as in claim 6, wherein said cooling pipes (117) are shaped in a ring and are arranged coaxial one above the other in cooperation with said inner surface of said cyclone chamber (18).

8. The device as claim 1, wherein at least a cooling device, to cool the surface of said at least one electrode, is arranged in cooperation with an inner surface of said cyclone chamber (18).

9. The device as in claim 8, wherein said cooling device is a microspray cooling device.

10. The device as in claim 1, wherein at least a layer (20) of cooling pipes (217) is arranged on a substantially horizontal plane above said cyclone chamber.

11. The device as in claim 10, wherein said layer (20) of cooling pipes (217) comprises a plurality of pipes (217) arranged concentric and with a high density with respect to each other.

12. The device as in claim 1, wherein the first cooling system comprises a cooled conduit (22) for conveying fumes from the first cooling system to the second cooling system

wherein said second cooling system (15) is able to convey fumes to said peripheral fume-discharge aperture (12) and comprises a series of cooling pipes arranged coaxial and one above the other so as to create a cooled channel (21) through which the fumes pass, and the cooled conduit (22), comprises cooling pipes (317) arranged in a spiral and is associated terminally with a cooled fume-discharge conduit (23).

13. The device as in claim 12, wherein said second system (15) to take in and convey fumes is associated, by means of the cooled conduit (22), with said peripheral fume-discharge aperture (12).

14. The device as in claim 12, wherein said first cooling system to take in and convey fumes comprises an autonomous fume-discharge conduit (28) for discharging fumes from the first cooling system to outside the furnace.

15. The device as in claim 12, wherein means (29) to regulate the flow of fumes is arranged between an outlet of said cyclone chamber (18) and an inlet to said cooled conduit (22).

16. The device as in claim 15, wherein said flow regulation means (29) comprise a movable gate.

17. The device as in claim 15, wherein said flow regulation means (29) comprise a fixed grid.

20. The device as in claim 1, wherein said turns (19) comprise pipes (17) wherein cooling fluid circulates.

21. The device as in claim 1, wherein the first cooling system comprises a cooled conduit (22) for conveying fumes from the first cooling system to the second cooling system.

5. A device to take in fumes and cool a roof (10) of an electric furnace, said furnace comprising at least a central zone surrounding a substantially central aperture (11) into which at least one electrode can be inserted and moved, and a peripheral fume-discharge aperture (12) to take in and discharge at least a portion of the fumes, said device comprising:

at least a first cooling system (13) for cooling the central zone surrounding said central aperture (11), and

a second cooling system (15) to take in and convey the fumes to outside the furnace,

wherein said first cooling system (13) comprises at least a circular cyclone chamber (18) comprising a plurality of turns (19) able to cool the central zone surrounding said central aperture (11), wherein said turns (19) comprise pipes (17) wherein cooling fluid circulates,

wherein said pipes (17) are arranged to create an annular-shaped cyclone spiral,

wherein the density of said turns (19) of said cyclone chamber (18) is at a maximum in substantial correspondence with an aperture (112) through which the fumes are discharged from the cyclone chamber (18), and at a minimum in a diametrically opposite position.

18. A device to take in fumes and cool a roof (10) of an electric furnace, said furnace comprising at least a central zone surrounding a substantially central aperture (11) into which at least one electrode can be inserted and moved, and a peripheral fume-discharge aperture (12) to take in and discharge at least a portion of the fumes, said device comprising:

at least a first cooling system (13) for cooling the central zone surrounding said central aperture (11), and

a second cooling system (15) to take in and convey the fumes to outside the furnace, comprising a third system (14) to cool the peripheral part of the roof (10),

wherein said third cooling system (14) comprises a plurality of cooling pipes (417) arranged on a substantially vertical plane between said central cyclone chamber (18) and a perimeter edge (16) of said roof (10), said pipes (417) being configured to form adjacent sections (24), substantially triangular or trapezoid in shape, defining an annular channel (25) for passing the fumes therethrough.

19. The device as in claim 18, wherein said third cooling system (14) further comprises a plurality of cooling pipes (27) lying on a substantially horizontal plane above said sections (24) and arranged at a distance from each other which increases from the periphery to the center of the roof (10) to achieve free intake areas for the fumes to pass which are as equal as possible.