US3814402A

US3814402A - Device for collecting gases from a converter

Info

Publication number: US3814402A
Application number: US00377229A
Authority: US
Inventors: A Maubon
Original assignee: Creusot Loire SA
Current assignee: Creusot Loire SA
Priority date: 1972-08-03
Filing date: 1973-07-09
Publication date: 1974-06-04
Anticipated expiration: 1991-06-04
Also published as: FR2194781B1; GB1383717A; FR2194781A1; CA989167A; BE803198A; DE2338339A1; DE2338339B2; IT986907B

Abstract

A device for collecting gases from the spout of a converter for use in a dust-collecting installation comprises a hood for connection to the dust-collecting installation, a skirt connected in fluid-tight manner to the hood and mounted to be stationary in use of the converter, a canopy surrounding with clearance the converter spout, connected to the skirt in fluid-tight manner, supported in a cut-away in a platform at the level of the converter spout and provided with a cut-away with a vertical plane normal to that including the converter trunnions, a shutter for closing the cut-away in the canopy, movable vertically relative thereto and connected to the skirt in fluid-tight manner, and pressure control means for maintaining the pressure within the skirt substantially equal to that externally of the skirt.

Description

June 4, 1974 DEVICE FOR COLLECTING GASES FROM A CONVERTER Primary Examiner-Gerald A. Dost Attorney, Agent, or Firm-Cameron, Kerkam, Sutton, Stowell & Stowell [57] ABSTRACT A device for collecting gases from the spout of a converter for use in a dust-collecting installation comprises a hood for connection to the dust-collecting installation, a skirt connected in fluid-tight manner to the hood and mounted to be stationary in use of the converter, a canopy surrounding with clearance the converter spout, connected to the skirt in fluid-tight manner, supported in a cut-away in a platform at the level of the converter spout and provided with a cutaway with a vertical plane normal to that including the converter trunnions, a shutter for closing the cut-away in the canopy, movable vertically relative thereto and connected to the skirt in fluid-tight manner, and pressure control means for maintaining the pressure within the skirt substantially equal to that externally of the skirt.

5 Claims, 3 Drawing Figures PATENIEDJuu 41914 FIG-.1-

PATENIEDJUN 41914 3314.402

SHEET 2 BF 3 FIGzZ PATENTEBJUH 41974 3814.402

sum 3 0F 3 DEVICE FOR COLLECTING GASES FROM A CONVERTER The present invention refers to a device for the collection of gases from a converter, for example for use with installation for collecting and extracting dust from the gases from the coverter.

The device is applicable to the collection of gases from a converter of any type.

There already exist collector devices for converter gas collector installations. Such a device is described, for example, in the French Patent No. 1,418,065 and its Additions. It comprises a hood, on the lower portion of which is mounted in a gastight manner a skirt which is flared out downwards, capping without touching the upper portion of the converter. In order to avoid the entry of air and exit of gases through the gap between the skirt and the converter, the collection suction is controlled to maintain constant the pressure difference between a point inside the skirt and a point outside the said skirt. The control system uses, as input information, the difference between the pressure in a calm zone in the skirt and the pressure in an external zone to control suction regulating means.

In these known devices the skirt is formed substantially as a body of revolution about the axis of revolution of the converter in its vertical position. It is given as large a volume as possible in order to enable it to absorb the coarse variations in the flow of gases leaving the converter. It is mounted to be displaced in the direction of its axis of revolution in order that it can be moved upwardly to clear the top of the converter so as, for exammple, to enable tilting of the converter. It can nevertheless be lowered far enough to partially cover the upper portion of the converter.

Devices of this type have a certain number of disadvantages. In order to improve the collection of the gases, hoods have been constructed in which the coverage of the spout of the converter is as large as possible. In practice, however, the collection of the gases is not perfect. Occasional discharges of gas outside the skirt always occur. These are then diluted in the atmosphere with nothing to oppose their rising and they will not be treated in the dust-extraction plant installed downstream of a duct extending the hood. Further, when the converter is not in the vertical position, for example, during pouring, smoke emission occurs, which smoke, as it is not collected, will not be treated by the dustextraction plant. For this reason there is the present tendency to provide secondary dust-extraction installations which, in order to be effective, have to be capable of treating considerable volumes of gas. It is to be noted also that it is a disadvantage to have to be able to raise and lower the skirt to enable tilting of the converter, because by reason of dimensions of the skirt, its lack of rigidity, and the distortions that it undergoes under the action of the flame, the control of these movements is not always entirely satisfactory and in any case requires time.

According to the invention there is provided a device for collecting gases from a converter comprising:

1. a hood adapted for connection to a dust-extraction installation;

2. a skirt adapted for surmounting the spout of the converter to be stationary during operation of the converter;

3. means coupling said skirt to said hook in a gastight manner;

4. platform means adapted to be located at the level of the spout of the converter and defining an opening which will, in use, be in register with the spout of the converter;

5. a flame resistance canopy in register with said opening in said platform and coaxial with said skirt, said canopy being cut away on that side which will, in use, be located to one side of the vertical plane including the horizontal axis of tilting of the converter, said canopy being shaped so as in use to leave clearance between it and the converter;

6. means coupling said canopy to said skirt in a gastight manner;

7. a shutter mounted in the cut-away in said canopy;

8. means for moving said shutter to open and close said cut-away in said canopy;

9. means coupling said shutter to said skirt in a gastight manner; and

10. means for controlling the pressure within said skirt in dependence on the pressure externally of said skirt.

An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a vertical axis section through a device according to the invention, taken along the line II in FIG. 3;

FIG. 2 is another vertical axial section through the device of FIG. 1 taken along the line IIII in FIG. 3; and

FIG. 3 is a plan view of the device of FIGS. 1 and 2.

As shown in the drawings, a converter 2 is surmounted by a gas collection device including a hood 3, the lower opening in which is located at a certain distance from the spout 21 of the converter. At the lower portion of the hood 3 is a skirt 4. This skirt 4 is of such a size that there is vertical clearance between it and the converter. The skirt is semi-fixed, that is to say, that it will be displaced only occasionally, during maintenance operations, but not during the course of refining. A sealing device 5, for example, of the sand-joint type, ensures gas-tightness between the hood and the skirt.

There is also provided a half-platform 1, which is generally independent of the rest of the collector device, is employed for the laying of refractories, is located at the level of the converter spout 21 and defines a cut-away ll surrounding the spout 21. In the cutaway 11 in the platform 1 is mounted a canopy 6 capping the converter without touching it. This canopy is supported by the platform 1, the skirt 4 itself resting on the canopy. Gas-tightness between the canopy 6 and the skirt 4 is provided by a gas-tight joint 8, for example, of sand-joint type.

The canopy 6 is provided, to one side of the vertical plane passing through trunnions 21, with a cut-away 61 to enable charging of the converter, pouring being effected in certain cases on the opposite side. The canopy forms a ceiling for the cases, its shape provides free clearance between it and the converter. The canopy 6 must resist flame and for this purpose it may be constructed of refractories and/or include a water-cooling system, for example of the water-jacket type.

A system for the control of the pressure within the skirt and canopy is provided which maintains the pressure within the skirt and canopy substantially equal to atmospheric pressure, so avoiding entry of air and escape of gas through the gap between the canopy and converter.

The pressure measurements for the control system are effected by sensors 7 measuring the pressure within the skirt and by external sensors (not shown) measuring the pressure externally of the device. The passage of gas between the hood and the upper portion of the converter 2 is controlled by means shown in FIG. 2, comprising a shutter 9 of cylindrical or other shape, movable vertically by means including cables 14, guide pulleys and a winch mechanism (not shown). Gastightness between the shutter 9 and the skirt 4 is effected by a plate 13 integral with the shutter, and which dips into a water chamber 12 arranged between the skirt 4 and a housing 10. Gas-tightness might also be ensured by an adjustable curtain. Gas-tightness at each side of the movable shutter 9 between it and the canopy 6 can be ensured by vertical labyrinth joints or by any other system.

The above-described device obviates the disadvantages of the known devices. In the above-described device the skirt is fixed during the normal performance of the converter. The device does not therefore need means for raising and lowering the skirt and a telescopic joint between the skirt and the hood. The cost of the installation and its maintenance is reduced and possible accidents are eliminated. The possibility of movement of the skirt may be preserved to enable maintenance operations but the means employed may be rudimentary and hence not very costly and certain in operation. In this device the gases are collected by the skirt and by a canopy surrounding the skirt, which improves the effectiveness of the collection of the gases during refinement or during pouring.

Due to the provisions of the skirt and canopy by making the collection fan apply a considerable suction during periods outside the blast periods, the dustextraction plant will treat the greater portion of the smoke emitted during charging, during waiting periods, and during pouring into ladles, which will substantially improve the anti-pollution efficacy of the plant.

Of course, without departing from the scope of the invention, variants and improvements in detail may be made as well as the use of equivalent means.

What is claimed is:

l. A device for collecting gases from a converter comprising:

1. a hood adapted for connection to a dust-extraction installation;

3. means coupling said skirt to saidhood in a gastight manner;

5. a flame resistant canopy in register with said opening in said platform and coaxial with said skirt, said canopy being cut away on that side which will, in use, be located to one side of the vertical plane including the horizontal axis of tilting of the converter, said canopy being shaped so as in use to leave clearance between it and the converter;

6. means coupling said canopy to said skirt in a gastight manner;

7. a shutter mounted in the cut-away in said canopy;

9. means coupling said shutter to said skirt in a gastight manner; and

10. means'for controlling the pressure within said skirt in dependence on the pressure externally of said skirt.

2.,A device according to claim 1 wherein said opening in said platforms means includes a cut-away in register with said cut-away in said canopy.

' 3. A device according to claim 1 including means for coupling said shutter to said canopy in a fluid-tight manner, said coupling means permitting relative movement therebetween.

4. A device according to claim 1 wherein said means coupling said shutter and said skirt include plate means mounted on to one of said shutter and said skirt, and a liquid bath into which said plate means extends mounted on the other of said'shutter and said skirt.

5. A converter installation comprising:

1. a converter;

2. a device for collecting gases from the spout of the converter and comprising:

a. a hood adapted for connection to a dustextraction installation;

b. a skirt surmounting the spout of the converter to be stationary during operation of said converter;

c. meanscoupling said skirt to said hood in a gastight manner;

d. platform means located at the level of said spout of said converter and defining an opening in register with said spout of said converter;

e. a flame resistant canopy in register with said opening in said platform and coaxial with said skirt, said canopy being cut away on that side which is located to one side of the vertical plane including the horizontal axis of tilting of said converter, said canopy being shaped so as to leave clearance between it and said converter;

f. means coupling said canopy to said skirt in a gastight manner;

g. a shutter mounted in the cut-away in said cano- Py; r

h. means for moving said shutter to open and close said cut-away in said canopy;

i. means coupling said shutter to said skirt in a gastight manner; and

j. means for controlling the pressure within said skirt in dependence on the pressure externally of said skirt.

Claims

1. A device for collecting gases from a converter comprising: 1. a hood adapted for connection to a dust-extraction installation; 2. a skirt adapted for surmounting the spout of the converter to be stationary during operation of the converter; 3. means coupling said skirt to said hood in a gas-tight manner; 4. platform means adapted to be located at the level of the spout of the converter and defining an opening which will, in use, be in register with the spout of the converter; 5. a flame resistant canopy in register with said opening in said platform and coaxial with said skirt, said canopy being cut away on that side which will, in use, be located to one side of the vertical plane including the horizontal axis of tilting of the converter, said canopy being shaped so as in use to leave clearance between it and the converter; 6. means coupling said canopy to said skirt in a gas-tight manner; 7. a shutter mounted in the cut-away in said canopy; 8. means for moving said shutter to open and close said cut-away in said canopy; 9. means coupling said shutter to said skirt in a gas-tight manner; and 10. means for controlling the pressure within said skirt in dependence on the pressure externally of said skirt.

2. A device according to claim 1 wherein said opening in said platforms means includes a cut-away in register with said cut-away in said canopy.

2. a device for collecting gases from the spout of the converter and comprising: a. a hood adapted for connection to a dust-extraction installation; b. a skirt surmounting the spout of the converter to be stationary during operation of said converter; c. means coupling said skirt to said hood in a gas-tight manner; d. platform means located at the level of said spout of said converter and defining an opening in register with said spout of said converter; e. a flame resistant canopy in register with said opening in said platform and coaxial with said skirt, said canopy being cut away on that side which is located to one side of the vertical plane including the horizontal axis of tilting of said converter, said canopy being shaped so as to leave clearance between it and said converter; f. means coupling said canopy to said skirt in a gas-tight manner; g. a shutter mounted in the cut-away in said canopy; h. means for moving said shutter to open and close said cut-away in said canopy; i. means coupling said shutter to said skirt in a gas-tight manner; and j. means for controlling the pressure within said skirt in dependence on the pressure externally of said skirt.

3. means coupling said skirt to said hood in a gas-tight manner;

3. A device according to claim 1 including means for coupling said shutter to said canopy in a fluid-tight manner, said coupling means permitting relative movement therebetween.

4. A device according to claim 1 wherein said means coupling said shutter and said skirt include plate means mounted on to one of said shutter and said skirt, and a liquid bath into which said plate means extends mounted on the other of said shutter and said skirt.

5. A converter installation comprising:

6. means coupling said canopy to said skirt in a gas-tight manner;

7. a shutter mounted in the cut-away in said canopy;

9. means coupling said shutter to said skirt in a gas-tight manner; and