Method and apparatus for dispensing a fluidizable solid from a pressure vessel

An improvement in a process for dispensing a fluidizable solid from the lower portion of a pressure vessel equipped with a weighing device, a closable supply, a discharge, and a source of three gas flows, a first of which is applied within the vessel at a level above the solid to be fluidized, a second of which is applied within said vessel in a lower portion thereof, and a third of which is applied within the discharge orifice of the vessel, which discharge orifice terminates in a chamber, which improvement involves determining the amount of solid dispensed and determining the throughflow of gas in relationship to the amount of solid dispensed to maintain a constant gas/solid ratio while maintaining the pressures such that the pressure applied to the lower portion of the vessel is greater than the pressure applied at a level above of the solids which, in turn, is greater than the pressure applied to the discharge orifice, all of which are greater than the pressure maintained within the chamber, and an apparatus for carrying out the process embodying control devices to maintain the desired constant predetermined gas/solid ratio.

Skip to: Description  ·  Claims  ·  References Cited  · Patent History  ·  Patent History
Description
BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a method of dispensing a fluidizable solid from a pressure vessel having a weighing device and closable supply and discharge, wherein of three gas flows which are supplied to the solid and are at various pressure values P.sub.1, P.sub.2, P.sub.3, the gas flow at medium pressure P.sub.2 is conducted into the vessel above the solid and the gas flow at relatively high pressure P.sub.1 is conducted into the lower vessel region for fluidizing the solid, and the gas flow or relatively low pressure P.sub.3 is conducted into the discharge connected thereto, the latter opening into a chamber at very low pressure P.sub.4, and the quantity of solid taken from the vessel being weighed and also to an apparatus for carrying out the method.

2. Discussion of the Prior Art

Some method steps and the apparatus required for these in the method described hereinbefore are known from publications: German Auslegeschrift No. 1,140,863, German Pat. No. 1,147,756 and German Auslegeschrift No. 1,148,938.

Further developments on the basis of these have led to a known procedure and an apparatus such as is illustrated in FIG. 1 and FIG. 3 of the accompanying drawings and will be described in detail hereinafter.

In FIG. 1, the apparatus includes a pressure vessel 1 having a closable charging aperture 2 through which solid 3 is introduced and a closable discharge 4, 19. Conduits 5, 7 and 8 are connected to gas pressure sources and a pressure reducing valve 12 is provided. The gas pressure conduit 7 leads into a chamber 9 formed between the vessel bottom end 10 and a second bottom end 11 which is arranged above bottom 10 and which is gas-pervious. A weighing device 14 for the solid 3 is connected to the vessel 1. There is a dispensing or consumption chamber 17 in which a very low pressure P.sub.4 prevails.

The known apparatus illustrated operates as follows:

With the discharge 4 closed, the pressure vessel 1 is filled with a solid 3 in powder form. The charging aperture 2 is closed and the gas pressure sources 5, 7, 8 are connected, the gas pressure source 5 being used for regulating the top pressure P.sub.2 the gas pressure source 7 for fluidizing the solid at pressure P.sub.1 and the gas pressure source 8 for supplying the "conveying gas" at pressure P.sub.3. The gas supplied to the chamber 17 and providing pressure P.sub.4 is the gas from the pressure source through 7 and the gas from the pressure source through 8. The prerequisite for conveying the fluidized solid is that the pressure relationship should be P.sub.1 >P.sub.2 >P.sub.3 >P.sub.4, P.sub.1 being the pressure of the second gas pressure source through 7, P.sub.2 the pressure of the first gas pressure source through 5, P.sub.3 the pressure of the third gas pressure source through 8 and P.sub.4 the pressure in the chamber 17. By means of the weighing apparatus 14 the quantity of solid to be dispensed from the vessel is determined. The known method is based on the relationship shown in FIG. 3, according to which the conveyed quantity of solid .[.O.]. .Iadd.Q .Iaddend.(e.g., in kg/min) depends on the pressure difference P.sub.2 -P.sub.3 : Q=const. (P.sub.2 -P.sub.3).

If the weighing apparatus 14 indicates for example that insufficient solid 3 is being conveyed, the top pressure P.sub.2 is increased above the solid 3 in the vessel 1. As FIG. 3 shows more particularly, with rising top pressure P.sub.2, plotted on the abscissa, the conveyed quantity of solid Q plotted on the ordinate is increased. Owing to the increased quantity of solid Q per volume unit conveyed, however, the pressure P.sub.3 of the conveying gas is also increased, but to a lesser extent than the top pressure P.sub.2. Consequently, with increasing top pressure P.sub.2 the difference between top pressure P.sub.2 and conveying pressure P.sub.3 increases, this being therefore in direct relationship to the throughflow of the quantity of solid. This relationship is usually used for controlling the throughflow of the solid concerned.

To reduce the conveyed solid quantity Q the top pressure P.sub.2 is reduced in accordance with the procedure described. A device for discharging gas can be provided additionally at the upper end of the vessel.

The control described does not influence the gas flow at relatively high pressure and the gas flow at relatively low pressure P.sub.2, P.sub.3, which exclusively determine the gas quantity and therefore the relation of gas to solid. The pressure reducing valve 12 which is associated with the third gas pressure through 8 and which operates like a proportional controller without a servo force, also discharges varying gas quantities if the pressure P.sub.4 in the chamber 17 of lowest pressure fluctuates. This would be the case for example when moving an immersion lance into a molten metal bath. The pressure reducing valve 12 provided has the result, when this pressure change occurs, of producing the conveyance of a smaller quantity of gas. On the other hand the pressure reducing valve 12 when the pressure P.sub.4 falls operates in such a manner that an increased quantity of gas is conveyed, in order thus to re-establish constant pressure conditions.

This has the result that for example when moving an immersion lance into and out of a torpedo ladle, with high throughflow quantities, liquid metal is thrown out of the ladle. To avoid this it is necessary to limit the degree to which the torpedo ladle is filled, thus reducing the working capacity.

In the constructional form described in FIG. 1 there also occurred when there was a considerable pressure drop in the chamber 17 of the very low pressure P.sub.4, blockages in the region of the chamber 9 since the opening of the pressure reducing valve 12 which results caused a corresponding pressure drop of P.sub.1 in the chamber 9 and the pressure P.sub.1 became too small in relation to the pressure P.sub.2. The results of this are inadequate fluidization of the solid and non-uniform dispensing.

SUMMARY OF THE INVENTION

Broadly, this invention contemplates an improvement in a process for dispensing a fluidizable solid from the lower portion of a pressure vessel having a weighing device, a closable supply, a discharge, a source of three gas flows, one of which is applied within the vessel at a level above the solid to be fluidized at a pressure P.sub.2, a second of which is applied within said vessel in the lower portion of said vessel at a pressure P.sub.1, a third of which is applied within the discharge orifice at a pressure P.sub.3, said discharge orifice terminating in a chamber maintained under a pressure P.sub.4, the improvement which comprises determining the amount of solid dispensed at said weighing device, determining the throughflow quantity of gas flow, said throughflow quantity of gas flow being the sum of the amount of gas at P.sub.1 and P.sub.3, and regulating the amount of gas and amount of solid to maintain a predetermined constant gas/solid dispensed ratio under conditions such that P.sub.1 >P.sub.2 >P.sub.3 >P.sub.4.

In a particularly desirable embodiment, this invention contemplates an improvement in an apparatus for dispensing a fluidizable solid from the lower portion of a pressure vessel having a weighing device, a closable supply, a discharge, a source of three gas flows, a first of which terminates within the vessel at a level above the solid to be dispensed in an upper portion thereof, a second of which terminates within the vessel in a lower portion thereof, a third of which terminates in said discharge, said discharge connected to a chamber, the improvement comprising means in association with said weighing device to determine the amount of a solid dispensed into said vessel, means for determining the sum of gas throughput of the gases from the second and third gas source, and regulating means for regulating the gas and solid to maintain a constant gas/solid ratio.

The apparatus of the present invention is particularly useful in carrying out a process wherein calcium carbide is fed through immersion lances into a pig iron desulphurization process whereby the amount of calcium carbide throughflow can be regulated to a desired high value in the range of 40 to 250 kg/min. while maintaining a constant ratio of gas to solid dispensed in the range of 2 to 20 Nl/kg. The present invention increases the efficiency of the pressure vessel and the solid fluidization process. It eliminates pressure fluctuations which in turn can affect the amount of solid fluidized into a subsequent process which can introduce less than optimum uniformity in the second process with respect to the process conditions and the products obtained. Additionally, excess quantities of gas emanating from the pressure vessel are eliminated such that only the amount of gas needed for the fluidization need be employed.

The present invention has as its object to improve the conditions obtaining with the above-described method.

According to the invention the throughflow quantity of solid and also the throughflow quantity of the gas flow, being that at relatively high and relatively low pressure (P.sub.1 and P.sub.3), are regulated in accordance with a predetermined constant gas/solid ratio so as to maintain that ratio during operation.

Preferably, the control of the throughflow quantity of the solid is effected by means of a pressure variation of the gas flow at medium pressure, P.sub.2.

It is of particular advantage to control the throughflow quantity of the gas flow (P.sub.1 and P.sub.3) by reference to the throughflow quantity of solid.

Preferably, to control the throughflow quantities of the gas flow only the gas flow of relatively low pressure, P.sub.3, is regulated.

The method according to the invention is particularly suitable in applications where solids in powder form are introduced into molten metal. It is more particularly suitable for the desulphurization of pig iron by means of an immersion lance, the solid throughflow (e.g., of calcium carbide) being regulated to a desired value of 40-250 kg/min, preferably 100-140 kg/min, and the gas/solid ratio to 2-20 Nl/Kg, preferably 4-10 Nl/kg.

To carry out the method according to the invention a particularly suitable apparatus includes a pressure vessel having a weighing apparatus, a closable charging aperture for the solid in the upper region, and in the lower region a closable discharge, a first regulatable gas pressure source connected to the upper vessel region to provide gas flow at medium pressure P.sub.2, a third regulatable gas pressure supply connected to the discharge to provide the gas flow at relatively low pressure P.sub.3, and a second gas pressure supply connected to the lower vessel region for the gas flow at relatively high pressure P.sub.1, the second gas pressure supply opening into a chamber between the vessel bottom end and a gas-pervious second bottom end arranged thereabove, and respective control devices being provided one for the gas throughflow quantity, being that from the second and third gas pressure supplies, and the other for the quantity of solid dispensed.

In a preferred constructional form, the control device for the gas throughflow quantity acts on a valve of the third gas pressure supply. The gas throughflow quantity of the second and third gas pressure supplies is ascertained with a meter.

In a further preferred constructional form, the control device for dispensing solid material receives from the weighing apparatus an actual value for the solid quantity dispensed and regulates the pressure P.sub.2 from the first gas pressure source in accordance with the deviation between actual and desired values.

BRIEF DESCRIPTION OF DRAWINGS

Referring again to the attached drawings:

FIG. 1 is a cross sectional diagrammatic view of an apparatus according to the prior art whose operation is described above;

FIG. 2 is a cross sectional diagrammatic view of the elevation of the apparatus of the present invention employed to carry out the claimed process; and

FIG. 3 is a graph showing the amount of conveyed material against pressure.

DESCRIPTION OF SPECIFIC EMBODIMENTS

It is particularly suitable to use a device wherein the actual value of the solid quantity dispensed is used for the control device for the gas throughflow quantity of the second and third gas pressure sources as a desired value. One embodiment of the invention is shown diagrammatically in FIG. 2 of the accompanying drawing and will be described in detail hereinafter.

Like the known apparatus previously described, this apparatus includes a pressure vessel 1 with a closable charging aperture 2 and a discharge 4 closable by a plug 19 for the solid 3. For fluidization, the double-walled bottom end is composed of the vessel bottom end 10, the second gas-pervious bottom end 11 and the chamber 9 situated therebetween. Opening from above into the pressure vessel 1 is a first gas pressure supply 5 under a pressure P.sub.2, into the chamber 9 opens the second gas pressure supply 7 at pressure P.sub.1 and into the discharge 4 the third gas pressure supply 8 at the pressure P.sub.3. From the discharge 4, a conduit leads to a chamber 17 which is at very low pressure P.sub.4. Here also conveyance requires that P.sub.1 >P.sub.2 >P.sub.3 >P.sub.4. The weighing device 14 is also provided for metering the quantity of solid dispensed at the pressure vessel 1.

A control device 15 is associated with the weighing device 14 which compares the actual value given by the weighing device with a desired value and in accordance with the result regulates the pressure P.sub.2 of the first gas pressure supply. There is also provided in the conduits leading from the second and third gas pressure sources 7, 8 to the chamber 9 and the discharge 4 a meter 16 for metering the gas throughflow quantity (being the gas at P.sub.1 plus that at P.sub.3) and also, connected thereto, a regulatable valve 18 or 18a. To regulate the gas throughflow quantity of the second and third gas pressure supplies from sources 7, 8 there is provided a further control device 13 which receives the actual value of the dispensed quantity of solid from weighing device 14 and sets up this value, taking into account a preset desired constant gas/solid ratio, as the appropriate desired value for the gas throughflow quantity. Thus the control devices 13,15 regulate the throughflow quantities of solid and gas to maintain the preset constant ratio.

In a particular example of the desulphurisation of pig iron with the immersion lance process the method of operation would be as follows:

Assume that the desired gas/solid ratio (Air/Calcium Carbide) is to amount to 5 Nl/kg. At the beginning of treatment the immersion depth of the lance is estimated and for example a pressure P.sub.2 is set by means of the first gas pressure source 5 in accordance with FIG. 3 to a value which corresponds approximately to the desired value of the solid flow. Likewise an initial position is selected for the valves 18 or 18a in the supply conduits of the second and third gas pressure supplies, so that the desired ratio of air to calcium carbide is approximately reached. Then the immersion lance is moved in and the treatment of the pig iron begun. The quantity of solid dispensed per unit of time is examined by the control device 15. If the actual value does not correspond to the .[.present.]. .Iadd.preset .Iaddend.desired value, the pressure P.sub.2 is adjusted. Also the actual value of the quantity of solid dispensed is continuously monitored by means of the control device 13 and taking the predetermined gas/solid ratio into account is converted into the desired value for the regulation of the air quantity.

According to above-described method within the invention uniform delivery of solid is achieved since the control of the volumes of solid and gas, taking normal conditions into account for the gas, avoids the use and any disadvantageous operation of the pressure reducing valve 12 which was described initially. The known pressure reducing valve 12 operating as a proportional controller without servo force is not necessary in the apparatus within the invention. However, to maintain desired pressure conditions a manually adjustable pressure reducing valve can be arranged at the valve 18 (in desulphurisation, e.g., 11/2 to 2 atmospheres excess pressure) between the gas pressure source 7, 8 and the valve 18,18a.

A further advantage is that pressure fluctuations in the chamber 17 do not cause any sudden changes in the gas delivery quantity, whereby pulsating conveyance is obviated. Furthermore there are no longer the excessive gas quantities delivered when the immersion lance is put in and taken out, which led to the throwing-out of molten metal initially described. Blockages owing to inadequate fluidisation no longer occur. It is of particular practical importance that the gas-solid ratio remains constant, which is of significance more particularly when using the invention in the field of metallurgy. For example, it has been found possible by the above method to increase to 95 percent the capacity of torpedo ladles, which was limited to 80 percent with the previously described known methods.

It should be stressed that the use of the above methodwithin the invention has been found to be advantageous also for the introduction of other fine-grain or powder-form solids into molten metal baths, e.g., for the introduction of silicon or aluminium into iron melts.

It is to be understood that the apparatus of the present invention is characterized by a first source of gas flow disposed in an upper region of the pressure vessel, i.e., terminating in the upper region or portion of the pressure vessel. By the term "upper region or portion" is meant the upper half of the vessel, similarly with respect to the second source of gas located in the lower portion of the vessel, it should be understood that the term "lower portion" refers to the bottom half of the vessel. Preferably, this latter second source of gas is disposed in an inverted conically shaped at the bottom of the vessel and terminates in a confined region defined by an inside wall of the inverted conically shaped zone and a liner disposed thereover which is gas-pervious. Preferably, the first gas source is disposed at the top of the vessel, and in any event, above the means for supplying solid to the vessel.

Claims

1. In a process for dispensing fluidizable solid from the lower portion of a pressure vessel having a weighing device at which said solid is dispensed, a closable supply, a discharge, a source of three gas flows, one of which is applied within the vessel at a level above the solid to be fluidized at a pressure P.sub.2, a second of which is applied within said vessel in the lower portion of said vessel at a pressure P.sub.1, a third of which is applied within the discharge orifice at a pressure P.sub.3, said discharge orifice terminating in a chamber maintained under a pressure P.sub.4, the improvement which comprises determining the amount of solid dispensed at said weighing device, determining the throughflow quantity of gas flow, said throughflow quantity of gas flow being the sum of the amount of gas having a pressure P.sub.1 and the amount of gas having a pressure P.sub.3 and regulating the amount of gas and amount of solid to maintain a predetermined constant gas/solid dispensed ratio under conditions such that P.sub.1 >P.sub.2 >P.sub.3 >P.sub.4.

2. An improvement according to claim 1 wherein the ratio of gas to solid dispensed is regulated by varying the pressure of the gas at pressure P.sub.2.

3. An improvement according to claim 2 wherein the throughflow quantity of gas is controlled in response to the throughflow quantity of solid determined to have been dispensed at said weighing device.

4. A method according to claim 1 wherein the throughflow quantity of the gas flow is controlled by varying only the gas flow at pressure P.sub.3 and maintaining the gas at pressure P.sub.1 at constant pressure.

5. A method according to claim 1, wherein the solid is in powder form and is dispensed into a metal melt.

6. A method according to claim 5, wherein a desulfurizing agent is fluidized and dispensed from said vessel at a rate between 40 and 250 kg/min, the gas/solid ratio is maintained at a value in the range from 2 to 20 Nl/kg and said agent is directed into a pig iron desulphurization process through an immersion lance.

7. A method according to claim 6 wherein the desulfurizing agent is calcium carbide.

8. A method according to claim 6 wherein the solid throughflow rate is between 100 and 140 kg/min and the gas/solid ratio is between 4 and 10 Nl/kg.

9. In an apparatus for dispensing a fluidizable solid from the lower portion of a pressure vessel having a weighing device, a closable supply, a discharge, a source of three gas flows, a first of which terminates within the vessel at a level above the solid in an upper portion thereof, a second of which terminates within the vessel in a lower portion thereof, a third of which terminates in said discharge, said discharge connected to a chamber, the improvement which comprises means in association with said weighing device to determine the amount of a solid dispensed into said vessel, means for determining the amount of gas throughput of the gases from second and third gas sources, and regulating means for regulating the gas and solid to maintain a constant gas/solid ratio.

10. An improvement according to claim 9 wherein said regulating means is in operative association with a flow controlling means on the third gas source.

11. An improvement according to claim 9 wherein means are provided in association with the first gas source to regulate the pressure thereof, said means responsive to an actual value measured by weighing device for solid dispensed.

12. An improvement according to claim 7 wherein a control device is provided to regulate the quantity of the gas throughflow which device is responsive to the actual value of quantity of solid dispensed.

13. In a device for dispensing a fluidizable solid from a pressure vessel having a weighing device, said vessel having in its upper portion a closable feed aperture and a gas line having a first controllable gas pressure source of pressure P.sub.2, said vessel having in the lower portion thereof a loosening bottom and a closable discharge opening, said discharge opening having a discharge line, said discharge line discharging into a chamber of pressure P.sub.4, said vessel having in the loosening bottom and in, the discharge line a second and third line discharge having a second controllable gas pressure source for a gas stream of pressure P.sub.1 and a third controllable gas pressure source at pressure P.sub.3, the improvement to maintain a gas quantity/solid quantity ratio constant which comprises a first regulating means for the solid quantity which first regulating means is operable to compare the actual value of the solid quantity measured by means of the weighing device which has a preset desired value, which first regulating means is operable to adjust the pressure of the gas stream of pressure P.sub.2 by means of said first controllable gas pressure source by synchronous adjustment thereof, a second regulating means for the gas quantity of the respective gas streams of pressures P.sub.1 and P.sub.3, which second regulating means receives the actual value of the gas quantity and the actual value of the solid quantity measured by the weighing device and, in the event of deviation from the gas quantity/solid quantity ratio to be maintained constant, adjusts the quantity by means of said second controllable gas pressure source to a constant preselected value, said device having magnitudes of pressures such that the following relationship is maintained: P.sub.1 >P.sub.2 >P.sub.3 >P.sub.4.

14. A device according to claim 13 wherein said second regulating means is responsive to a measuring device arranged following the second controllable gas pressure source and adjusts the gas quantity of gas at pressures P.sub.1 and P.sub.3, respectively, through control valves.

15. A device according to claim 13 wherein said second regulating means adjusts only the gas quantity of the gas stream at pressure P.sub.3 by means of a control valve..Iadd. 16. A process according to claim 1 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 17. A process according to claim 16 wherein said molten metal is disposed in a torpedo ladle..Iaddend..Iadd. 18. A process according to claim 2 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at pressure P.sub.3..Iaddend..Iadd. 19. A process according to claim 18 wherein said molten metal is disposed in a torpedo ladle..Iaddend..Iadd. 20. A process according to claim 4 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 21. A process according to claim 20 wherein said molten metal is disposed in a torpedo ladle..Iaddend..Iadd. 22. A process according to claim 5 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 23. A process according to claim 22 wherein said molten metal is disposed in a torpedo ladle..Iaddend..Iadd. 24. A process according to claim 5 wherein said molten metal is disposed in a torpedo ladle..Iaddend..Iadd. 25. A process according to claim 5 wherein said gas/solid ratio is maintained at a value in the range from 2 to 20 Nl/kg..Iaddend..Iadd. 26. A process according to claim 5 wherein said powder is a desulfurizing agent..Iaddend..Iadd. 27. A process according to claim 5 wherein said solid comprises silicon..Iaddend..Iadd. 28. A process according to claim 5 wherein said solid comprises aluminum..Iaddend..Iadd. 29. A process according to claim 6 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 30. A process according to claim 29 wherein said molten metal is disposed in a torpedo ladle..Iaddend..Iadd. 31. An apparatus according to claim 12 wherein said discharge is disposed vertically below said closable supply..Iaddend..Iadd. 32. An apparatus according to claim 9 wherein said discharge is disposed vertically below said closable supply..Iadd. 33. An apparatus according to claim 11 wherein said discharge is disposed vertically below said closable supply..Iaddend..Iadd. 34. A device according to claim 13 wherein said discharge line is disposed vertically below said discharge opening..Iaddend..Iadd. 35. In a process for dispensing via an immersion lance immersed into a metal melt fluidizable solid from the lower portion of a pressure vessel having a weighing device at which said solid is dispensed, a closable supply, a discharge, a source of three gas flows, one of which is applied within the vessel at a level above the solid to be fluidized at a pressure P.sub.2, a second of which is applied within said vessel in the lower portion of said vessel at a pressure P.sub.1, a third of which is applied within the discharge orifice at a pressure P.sub.3, said discharge orifice terminating via said immersed lance in said metal melt at a pressure P.sub.4, the improvement which comprises determining the amount of solid dispensed at said weighing device, determining the throughflow quantity of gas flow, said throughflow quantity of gas flow being the sum of the amount of gas at a pressure having a pressure P.sub.1 and the amount of gas having a pressure P.sub.3 and regulating the amount of gas and amount of solid to maintain a predetermined constant gas/solid dispensed ratio under conditions such that P.sub.1 >P.sub.2 >P.sub.3 >P.sub.4..Iaddend..Iadd. 36. A process according to claim 35 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 37. A process according to claim 36 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 38. A process according to claim 35 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 39. A process according to claim 35 wherein the ratio of gas to solid dispensed is regulated by varying the pressure of the gas at pressure P.sub.2..Iaddend..Iadd. 40. A process according to claim 39 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 41. A process according to claim 39 wherein the throughflow quantity of gas is controlled in response to the throughflow quantity of solid determined to have been dispensed at said weighing device..Iaddend..Iadd. 42. A process according to claim 41 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 43. A process according to claim 41 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 44. A process according to claim 43 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 45. A process according to claim 39 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 46. A process according to claim 45 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 47. A process according to claim 35 wherein the through flow quantity of gas flow is controlled by varying only the gas flow at pressure P.sub.3 and maintaining the gas at pressure P.sub.1 at constant pressure..Iaddend..Iadd. 48. A process according to claim 47 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 49. A process according to claim 47 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 50. A process according to claim 49 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 51. A process according to claim 35 wherein the solid is in powder form..Iaddend..Iadd. 52. A process according to claim 51 wherein said solid is a desulfurizing agent..Iaddend..Iadd. 53. A process according to claim 51 wherein said solid comprises silicon..Iaddend..Iadd. 54. A process according to claim 51 wherein said solid comprises aluminum..Iaddend..Iadd. 55. A process according to claim 51 wherein a desulfurizing agent is fluidized and dispensed from said vessel at a rate between 40 and 250 kg/min, the gas/solid ratio is maintained at a value in the range from 2 to 20 Nl/kg and said agent is directed into a pig iron desulfurization process through said immersion lance..Iaddend..Iadd. 56. A method according to claim 55 wherein the solid throughflow rate is between 100 and 140 kg/min and the gas/solid ratio is between 4 and 10 Nl/kg..Iaddend..Iadd. 57. A process according to claim 55 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 58. A method according to claim 55 wherein the desulfurization agent is calcium carbide..Iaddend..Iadd. 59. A process according to claim 58 wherein said desulfurizing agent is calcium carbide..Iaddend..Iadd. 60. A process according to claim 55 wherein said fluidizable solid is passed downwardly vertically from said pressure vessel into said line containing said discharge orifice and containing gas at a pressure P.sub.3..Iaddend..Iadd. 61. A process according to claim 60 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 62. A process according to claim 51 wherein said gas/solid ratio is maintained at a value in the range from 2 to 20 Nl/kg..Iaddend..Iadd. 63. A process according to claim 62 wherein said powder is fluidized and dispensed from said vessel at a rate between 40 and 250 kg/min..Iaddend..Iadd. 64. In an apparatus for dispensing a fluidizable solid via an immersion lance, into a metal melt into which said lance is immersed, from the lower portion of a pressure vessel having a weighing device, a closable supply, a discharge, a source of three gas flows, a first of which terminates within the vessel at a level above the solid in an upper portion thereof, a second of which terminates within the vessel in a lower portion thereof, a third of which terminates in a discharge line, said discharge line discharging into a metal melt via an immersion lance immersed in said metal melt, the improvement which comprises means in association with said weighing device to determine the amount of a solid dispensed into said metal melt, means for determining the amount of gas throughput of the gases from second and third sources, and regulating means for regulating the gas and solid to maintain a constant gas/solid ratio..Iaddend..Iadd. 65. An apparatus according to claim 64 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 66. An apparatus according to claim 64 wherein said discharge is disposed vertically below said closable supply..Iaddend..Iadd. 67. An apparatus according to claim 66 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 68. An apparatus according to claim 64 wherein said regulating means is in operative association with a flow controlling means on the third gas source..Iaddend..Iadd. 69. An apparatus according to claim 68 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 70. An apparatus according to claim 68 wherein said discharge is disposed vertically below said closable supply..Iaddend..Iadd. 71. An apparatus according to claim 70 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 72. An apparatus according to claim 64 wherein means are provided in associated with the first gas source to regulate the pressure thereof, said means responsive to an actual value measured by weighing device for solid dispensed..Iaddend..Iadd. 73. An apparatus according to claim 72 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 74. An apparatus according to claim 72 wherein said discharge is disposed vertically below said closable supply..Iaddend..Iadd. 75. An apparatus according to claim 74 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 76. An apparatus according to claim 64 wherein a control device is provided to regulate the quantity of the gas throughflow which device is responsive to the actual value of the quantity of solid dispensed..Iaddend..Iadd. 77. An apparatus according to claim 76 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 78. An apparatus according to claim 76 wherein said discharge is disposed vertically below said closable supply..Iaddend..Iadd. 79. A process according to claim 78 wherein said powder is fluidized and dispensed from said vessel at a rate between 40 and 250 kg/min..Iaddend..Iadd. 80. An apparatus according to claim 78 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 81. In a device for dispensing a fluidizable solid via an immersion lance into a metal melt into which said lance is immersed from a pressure vessel having a weighing device, said vessel having in its upper portion a closable feed aperture and a gas line having a first controllable gas pressure source of pressure P.sub.2, said vessel having in the lower portion thereof a loosening bottom and a closable discharge opening, said discharge opening having a discharge line, said discharge line discharging into a metal melt of pressure P.sub.4 via an immersion lance immersed into said metal melt, said vessel having in the loosening bottom and in the discharge line a second and third line discharge having a second controllable gas pressure source for a gas stream of pressure P.sub.1 and a third controllable gas pressure source at pressure P.sub.3, the improvement to maintain a gas quantity/solid quantity ratio constant which comprises a first regulating means for the solid quantity which first regulating means is operable to compare the actual value of the solid quantity measured by means of the weighing device which has a preset desired value, which first regulating means is operable to adjust the pressure of the gas stream of pressure P.sub.2 by means of said first controllable gas pressure source by synchronous adjustment thereof, a second regulating means for the gas quantity of the respective gas streams of pressures P.sub.1 and P.sub.3, which second regulating means receives the actual value of the gas quantity and the actual value of the solid quantity measured by the weighing device and, in the event of deviation from the gas quantity/solid quantity ratio to be maintained constant, adjusts the quantity by means of said second controllable gas pressure source to a constant preselected value, said device having magnitudes of pressure such that the following relationship is maintained: P.sub.1 >P.sub.2 >P.sub.3 >P.sub.4..Iaddend..Iadd. 82. A device according to claim 81 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 83. A device according to claim 81 wherein said second regulating means is responsive to a measuring device arranged following the second controllable gas pressure source and adjusts the gas quantity of gas at pressures P.sub.1 and P.sub.3, respectively, through control valves..Iaddend..Iadd. 84. A device according to claim 83 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 85. A device according to claim 81 wherein said second regulating means adjusts only the gas quantity of the gas stream at pressure P.sub.3 by means of a control valve..Iaddend..Iadd. 86. A device according to claim 85 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 87. A device according to claim 81 wherein said discharge line is disposed vertically below said discharge opening..Iaddend..Iadd. 88. A device according to claim 87 wherein said metal melt is disposed in a torpedo ladle..Iaddend..Iadd. 89. A process according to claim 87 wherein said desulfurizing agent is calcium carbide..Iaddend.

Referenced Cited
U.S. Patent Documents
49052 July 1865 Bessemer
52656 February 1866 Kerpely
94994 September 1869 Bessemer
193551 July 1877 Reese
905948 December 1908 Stromborg
987704 March 1911 Deemer
1038781 September 1912 Myles et al.
1151332 August 1915 Baggaley
1203703 November 1916 Chevalier
1231327 June 1917 Brauchler
1484465 February 1924 Billings
1491433 April 1924 Stebbins
1505281 August 1924 Nagelvoort
1541778 June 1925 Agricola
1587600 June 1926 Nielsen
1646728 October 1927 Evans
1666477 April 1928 Stebbins
1709389 April 1929 Davis
1785503 December 1930 Spring
1809436 June 1931 Carman
1921060 August 1933 Williams
1922037 August 1933 Hardy
1949731 March 1934 Soldatoff
1968917 August 1934 Soldatoff
2077568 April 1937 Kinzel
2181095 November 1939 Ness
2198625 April 1940 Koppers
2219208 October 1940 Knight
2258850 October 1941 Eulenstein et al.
2291221 July 1942 Gibson
2296309 September 1942 Reeves
2485760 October 1949 Millis et al.
2502259 March 1950 Hulme
2509983 May 1950 Morrow
2547015 April 1951 Kirkbride
2561396 July 1951 Matheson
2577764 December 1951 Hulme
2586818 February 1952 Harms
2589124 March 1952 Packie
2608446 August 1952 La Pota
2636642 April 1953 Gorin
2664338 December 1953 Cornell
2665982 January 1954 Crego et al.
2676142 April 1954 Crowley, Jr.
2676852 April 1954 Kirkbride
2684870 July 1954 Berg
2684890 July 1954 Lapple et al.
2692196 October 1954 Hulme
2697685 December 1954 Fahnestock et al.
2711350 June 1955 Delaplaine
2734782 February 1956 Galle
2762701 September 1956 Crego et al.
2779675 January 1957 Vennerholm et al.
2803533 August 1957 Bieniosek et al.
2806781 September 1957 Shepherd et al.
2814531 November 1957 Murray, Jr.
2858125 October 1958 Clenny et al.
2863764 December 1958 Spangler et al.
2870004 January 1959 Estes et al.
2891782 June 1959 Blackman et al.
2906616 September 1959 Allard et al.
2909422 October 1959 Schwabe
2963364 December 1960 Crockett et al.
2992097 July 1961 Spence
3001829 September 1961 De Saint-Martin
3001829 September 1961 Saint-Martin
3001864 September 1961 Muller et al.
3018021 January 1962 Gorand et al.
3060015 October 1962 Spolders et al.
3091369 May 1963 Sackett
3099552 July 1963 Landig et al.
3124450 March 1964 Mataschkovitz et al.
3157492 November 1964 Matuschkovitz
3192037 June 1965 Haucke et al.
3194539 July 1965 Hanne-Wiame
3212881 October 1965 Dunn, Jr. et al.
3230016 January 1966 Gilbert et al.
3240588 March 1966 Finkl
3258328 June 1966 Goss et al.
3268326 August 1966 Harders
3333774 August 1967 Demaison
3336132 August 1967 McCoy
3367646 February 1968 Robertson et al.
3368885 February 1968 Volianik
3459536 August 1969 Touzalin et al.
3467167 September 1969 Mahin
3512957 May 1970 Brotzmann et al.
3545960 December 1970 McClellan et al.
3547622 December 1970 Hutchinson
3551139 December 1970 Schokkenbroek
3567432 March 1971 Wardell
3575695 April 1971 Miyashita et al.
3598383 August 1971 Moore
3604758 September 1971 Flain et al.
3955966 May 11, 1976 Meichsner
4049442 September 20, 1977 Freissmuth et al.
3598573 August 1971 Freissmuth et al.
3694037 September 1972 Feder
3702151 November 1972 De Blok et al.
3715202 February 1973 Kosmider et al.
3716352 February 1973 Ooi et al.
3718173 February 1973 Snow
3858640 January 1975 Sifferien
3876421 April 1975 Takemura
3885957 May 1975 Richter et al.
3891196 June 1975 Forster et al.
3929464 December 1975 Todd et al.
3980469 September 14, 1976 Forster et al.
3992195 November 16, 1976 Klapdar et al.
3998625 December 21, 1976 Koros
4067730 January 10, 1978 Klapdar et al.
4123258 October 31, 1978 Klapdar et al.
3432208 March 1968 Hill
3604758 September 1971 Flain et al.
3694037 September 1972 Feder
3702151 November 1972 De Blok et al.
3715202 February 1973 Kosmider et al.
3716352 February 1973 Ooi et al.
3718173 February 1973 Snow
3858640 January 1975 Sifferien
3876421 April 1975 Takemura
3885957 May 1975 Richter et al.
3891196 June 1975 Forster et al.
3929464 December 1975 Todd et al.
3980469 September 14, 1976 Forster et al.
3992195 November 16, 1976 Klapdar et al.
3998625 December 21, 1976 Koros
4036635 July 19, 1977 Klapdar et al.
4067730 January 10, 1978 Klapdar et al.
4123258 October 31, 1978 Klapdar et al.
Foreign Patent Documents
183097 September 1955 ATX
194423 January 1958 ATX
207395 January 1960 ATX
253417 May 1963 ATX
246025 March 1966 ATX
254919 June 1967 ATX
225887 December 1959 AUX
436031 May 1973 AUX
495995 September 1978 AUX
505018 August 1979 AUX
795333 May 1973 BEX
828017 August 1975 BEX
472968 April 1951 CAX
551500 January 1958 CAX
1012351 June 1977 CAX
1014750 August 1977 CAX
1045824 January 1979 CAX
1062916 September 1979 CAX
1078624 June 1980 CAX
676778 June 1939 DE2
1015609 September 1957 DEX
1035907 August 1958 DEX
1039237 September 1958 DEX
974714 April 1961 DEX
1137457 October 1962 DEX
1140863 December 1962 DEX
1147756 April 1963 DEX
1148938 May 1963 DEX
1189453 November 1965 DEX
1408188 October 1968 DEX
1433691 March 1969 DEX
1292693 April 1969 DEX
1803377 May 1969 DEX
1817507 August 1969 DEX
1508208 October 1969 DEX
2032845 February 1971 DEX
1758835 March 1971 DEX
2106536 September 1971 DEX
1802991 February 1972 DEX
1642954 March 1972 DEX
2205090 September 1972 DEX
2219818 October 1973 DEX
2153379 November 1973 DEX
2209902 January 1975 DEX
1912733 October 1979 DEX
457645 September 1913 FRX
1091102 April 1955 FRX
1219334 May 1960 FRX
1238314 July 1960 FRX
1250107 November 1960 FRX
1280116 November 1961 FRX
1467158 December 1966 FRX
1596638 July 1970 FRX
2051745 September 1971 FRX
2087972 July 1972 FRX
252267 March 1927 ITX
22204 July 1970 JPX
26612 August 1971 JPX
100311 December 1973 JPX
31518 August 1974 JPX
183547 May 1963 SEX
183691 May 1963 SEX
211838 August 1966 SEX
341412 December 1971 SEX
6904 May 1972 SEX
192466 November 1974 SEX
371469 October 1963 CHX
2243 1879 GBX
622419 June 1949 GBX
800877 September 1958 GBX
818697 August 1959 GBX
829274 March 1960 GBX
837587 June 1960 GBX
892550 March 1962 GBX
896539 May 1962 GBX
915637 January 1963 GBX
918104 February 1963 GBX
940506 October 1963 GBX
943810 December 1963 GBX
954838 September 1965 GBX
1014827 December 1965 GBX
1037518 March 1963 GBX
1046675 October 1966 GBX
1073864 June 1967 GBX
1164026 September 1969 GBX
1223385 February 1971 GBX
1372672 November 1974 GBX
1434650 May 1976 GBX
1435189 May 1976 GBX
1450013 September 1976 GBX
1479222 July 1977 GBX
1556703 November 1979 GBX
Other references
  • Der IRSID-Staubzuteiler fur den OLP-Konverter (Siemens & Halske AG). La Technique Moderne 55, 11 505-11 (Nov. 1963) "The Utilization of Pulverulent Materials in Iron Metallurgy", C. Roederer and J. Rouanet. "Applications en Acierie Electrique de la Technique IRSID d'Insufflation de Matieres Pulverulentes", Revue de Metallurgie, Sep. 1963, by A. De Lavareille, J. Raguin, P. Vayssiere, B. Trentini, with translation. "Calcium Carbide Injection-A New Foundry Tool", American Foundryman, Apr. 1954, vol. 25, No. 4, pp. 34-44, by H. E. Henderson and J. M. Crockett. "Erfahrungen bei der Nachentschwefelung von Roheisen", Stahl und Eisen, Heft 6, 89, Mar. 20, 1969, by Von Hans-Peter Schulz, with side-by-side translation. Electric Furnace Proceedings, vol. 24, Phila., 1966, "Desulphurization Prior to the Boil" by Charles W. Briggs. Journal of the Iron and Steel Institute, vol. 204, Jan. 1966, Part 1, "Effect of Calcium Carbide on Desulphurization Kinetics", pp. 226-229, by P. A. Hitchcock and A. Mitchell. Aufbereitungs-Technik, Nr. 10, pp. 603-613, by Dipl.-Ing. M. Weber. von Helmut Knuppel, "Desoxydation und Vakuumbehandlung von Stahlschmelzen" 1970, pp. 62/69 and 275-283. von Bernhard Osann "Lehrbuch der Eisenhuttenkunde" 1921, pp. 540-545 and 1017-1022. "Die Physikalische Chemie der Eisen und Stahlerzeugung" 1964, pp. 256 and 260-261 and 328-329. "SKW-Kundeninformation", No. 4, Jan. 1972, pp. 2-10. "Stahl und Eisen" 1972, pp. 784-789 and pp. 1091-1092. Von E. Kudielka "Kalzium bei der Herstellung von Stahl and Eisen" Radex-Rundschau, 1965, issue 2, pp. 483-486. Von E. K. Modl "Die Anwendung von Spulgas-und Einblaseverfahren in der Giesserie" Jahrgang 48, issue 21, Oct. 19, 1961, pp. 639-647. Von Nils. F. Grevillius, Lars-Erik Carlsson and Lars Hellner, "Neues Stahlentschwefelungsverfahren" Neue Hutte 16 Jg. issue 2, Feb. 1971, pp. 72-77. Von W. Maschlanka, Kehl am Rhein, H. Knahl and A. Freissmuth, "Desulfurization of Pig Iron by Blowing in Calcium Carbide and Calcium Cyanimide with Additives", Radex-Rundschau, vol. 5, 1970, pp. 314-323 and English Translation thereof. Von Manfred Wahlster, Hermann Maas, Horst Abratis and Alok Choudhury "Reaction zwischen feuerfesten Stoffen des Systems SiO.sub.2 --Al.sub.2 O.sub.3 und Manganhaltigen Eisenschmelzen" Archiv fur das Eisenhuttenwesen issue 1, Jan. 1970, pp. 37-42. "Essais de desulfuration de la fonte liquide par injection de carbure de calcium pulverise" Tetsu to Hagane, Mar. 1955, pp. 193-195. Kiichi Narita, Akitsu Tomita, Yasuo Hirooka and Yoshitomo Satoh "Desulphurization of Molten Pig Iron by Means of Injection Method" Tetsu-to-Hagane, Journal of the Iron and Steel Institute of Japan, No. 13, vol. 56, Nov. 1970, pp. 1602-1612 (pp. 28-38). Von. M. Wahlster. A. Choudhury, A. Knahl and A. Freissmuth "Die Wirking Kalziumhaltiger Legierungen auf Desoxydation, Entschwefelung und mechanische Eigenschaften von Feinkornbaustahl" Radex-Rundschau, 1969, Issue 2, pp. 478-494. Von Rolf Ebert and Winfried Wenzel "Versuche zur Nachbehandlung von Frussigem Roheisen" Neue Hutte, Issue 1, Nov. 1962, pp. 665-670. Von Bogdandy, Rutsch and Stranski "Gasaustausch Zwischen Blasen und Gaslosenden Flussigkeiten" Chemie-Ing. Tech. 31, Jahrg. 1959, Nr. 9. 580-582. Werner Coupette "Die Vakuum-Behandlung des Flussigen Stahles" Rudolf A. Lang Verlag, Wiesbaden, Esch/Taunus, 1967, pp. 128-133. "Hand Book of Iron and Steel" Fig. 8.124 in page 668, printed Mar. 1971 by Maruzen pp. 16, 17, 668-669-and partial translation. Aikoh Co., Ltd. "Progress in Processes for Melting Steel under Vacuum and for Degasifying under Vacuum" printed by Japanese Iron and Steel Association, 1969, pp. 147-157. Aikoh Co., Ltd. "Iron & Steel", p. 85, No. 3, vol. 55, 1969. Aikoh Co., Ltd. "Manufacture of Cast Iron and Steel" Table 10.4 in page 458, printed by Yohkendo, 1961, pp. 1, 458-459, 552 and partial translation. S. Kobayashi, "On the Deoxidation of a Liquid Iron with Argon-Calcium Bubbles", Iron and Steel, No. 8, vol. 56, 1970, pp. 998-1013. H. Schrewe and G. Diederich "Operating Results of Wide Slab Row Casting Plants" Journal of the West of Scotland Iron and Steel Institute" Paper No. 596, Mar. 27, 1969, pp. 33-64. Bernard Trentini, Pierre Vayssiere, Antoine de Lavareille, and Jean Raguin "IRSID Powder Blowing Techniques Applied to Electric Steel-Making" Proceedings of Electric Furnace Conference, 1963, pp. 28-42. E. F. Kurzinski, Mktg. Mgr., Metals and Mining Industries, Fischer & Porter Co., Warminster, Pa. "Desulfurization of Iron-Status and Evaluation" Apr. 1976, pp. 00042-00054. Eckehard Forster, Wilhelm Klapdar, Helmut Richter, Heinrich-Wilhelm Rommerswinkel, "Deoxidation and Desulphurisation by Blowing of Calcium Compounds into Molten Steel and Its Effects on the Mechanical Properties of Heavy Plates" Stahl & Eisen 94 (May 23, 1974) No. 11, pp. 474-485. Heinrich-Wilhelm Rommerswinkel, "Untersuchung Zum Ablauf der Desoxydation und Entschwefelung Beim Einblasen Von Kalziumkarbid in Stahlschmelzen" Jul. 9, 1973, pp. 1-31 plus charts etc. Robert C. Weast, and Melvin J. Astle "CRC Handbook of Chemistry and Physics" p. d-221 "Vapor Pressure of the Elements" Rudolf Loebel CRC Press, Inc. Boca Raton, Fla. 33431. J. W. Menter "The Heterogeneity of Steel" Journal of the Iron and Steel Institute, Apr. 1971, pp. 249-263. B. Trentini, P. Vayssiere, and C. Roederer "OLP Steelmaking Recent Studies and Industrial Progress" Journal of Metals, Jun. 1961, pp. 418-421. B. Trentini and M. Allard, "Refining Pig-Iron with Oxygen and Lime Powder" IRSID's Oxygene-Lance-Poudre (OLP) Process" Iron and Coal Trades Review, Oct. 10, 1958, pp. 871-874. B. Trentini and M. Allard "O.L.P.: Oxygen, Lime-Powder Injection a New Steelmaking Process" Journal of Metals, Jul. 1958, pp. 466-470. B. Trentini, P. Vayssiere, and C. Roederer "Technology and Metallurgy of the OLP Process" Journal of Metals, Aug. 1962, pp. 579-583, No. 8, 14. SKW Trostberg AG, May 14, 1971 Proceedings and translation, (Certified) pp. 33-45; 46-63; 97-116. H. J. Langhammer and D. Danckert; "Comparison of Processes for Continuous and Discontinuous Desulphurization with Different Desulphurizing Agents" Radex-Rundschau, Issue 1, 1972, pp. 3-26 with English version. S. D. Baumer and P. M. Hulme "Desulphurizing Molten Iron with Calcium Carbide" Journal of Metals, Apr. 1951-pp. 313-318. G. P. Dahm, H. C. Barnes, and C. E. Bieniosek, Progress Report "Fluidization-Injection Process for Desulphurizing and Upgrading Cast Iron" Trans. Amer. Foundrym. Soc. 63 (1955) pp. 511-523. Daniel W. Watkins and J. R. McFarland "Desulphurization of Blast Furnace with Injected Calcium Carbide" Proc. Blast Furn. Coke Ovens Raw Materials Comm. AIME, vol. 15, (1956) pp. 138-147. C. E. Wood, E. P. Barret and F. W. Holbrook "Desulphurization of Pig Iron with Calcium Carbide" Transactions of the American Institute of Mining and Metallurgical Eng. vol. 140, Iron and Steel Div., 1940, pp. 87-105. J. V. Harding and C. N. Walters, "Injection of Powders into Molten Metals with Inert Gases (British Investigations and Installations)" Steel & Coal, Jun. 29, 1962, No. 72, pp. 1243-1249. P. K. Chakravarty, V. G. Paranjpe and S. Visvanathan "Possibilities of Desulphurizing Blast-Furnace Hot Metal" Part II: By Injecting Fluidized Agents, TISCO 4, (1957) pp. 80-88. Edward J. Dunn, Jr. "Rapid Desulfurization to 0.002 Percent Sulphur" Modern Casting, No. 6 (1961), pp. 90-95, AFS New Technology. E. J. Whittenberger, A. J. Deacon and L. C. Hymes, "Desulphurization of Basic Iron with Calcium Carbide" Blast Furnace and Steel Plant-Jun./Jul. 1956, pp. 644-689 and 747-754. S. L. Gertsman, "Desulfurization of Iron and Steel" Foundry, Aug. 1958, pp. 48-53. J. N. Hornak and E. J. Whittenberger "Desulphurization of Molten Iron" Proc. Blast. Furn. Coke Ovens Raw Materials Comm. AIME vol. 15, (1956) pp. 125-137. No. 23. John A. DeHuff and R. Schneidewind "Calcium Carbide Desulfurization by the Injection Process" Trans. Amer. Foundrym. Soc. 63 (1955) No. 22, pp. 524-532. R. B. Coates and J. V. Harding "The Batch Desulphurization of Molten Iron by the Calcium Carbide Injection Process" BCIRA-J. 8 (1960) No. 13, pp. 89-111, (Report No. 530). Harvey E. Henderson and Philip M. Hulme "Calcium Carbide Injection . . . Is New Tool in Gray Iron Metallurgy" Foundry, Apr. 1953, pp. 86-91 and 211-217. L. Marples and J. Pears, "Desulphurization of Basic Electric Arc Furnace Steel by the Injection of Powdered Materials" Journal of the Iron and Steel Institute, Jun. 1960, pp. 195-201. "Stainless Steel Making Calcium Carbide Injection Used for Sulphur Removal" Iron and Coal, Sep. 1, 1961, pp. 461-462. S. Santen and B. Ohman "Techniques for Obtaining Extremely Low Contents of Sulphur in Steel under Oxidizing and Reducing Conditions" Swedish Academy of Engineering Science Stockholm 1971, Report, 196-1, pp. 7-19. R. B. Coates and H. J. Leyshon, "A Porous Plug for Ladle Desulphurization and Carburization of Iron", Report 745, British Cast Iron Research J. 12, Jul. (1964) pp. 479-494. R. B. Coates, and H. J. Leyshon, "Desulphurization of Cast Iron" Report 747, British Cast Iron Research J. 12, Jul. 1964, pp. 507-518. K. Knaggs, M. Sewell and J. Turton; "The Production of Steel of Low Sulphur Content" Journal of the Iron and Steel Institute, Jan. 1962, pp. 4-18. J. N. Hornak and E. J. Whittenberger "The Desulfurization of Molten Iron" Journal of Metals, Apr. 1956, pp. 425-429. Von P. Flament and A. Hamilius, "Large Scale Desulphurization Tests with CaD 7525 Metallurgy for the Production of LD Melts with Low Sulphur Contents" Radex-Rundschau, Issue 1, 1972, pp. 27-34. Von Wilhelm vor dem Esche, Manfred Haucke, Hermann-Josef Kopineck, Wilhelm Wolf and Helmut Wysocki "Entschwefeln Von Roheisen Mit Feinkalk Ausserhalt des Hockofens" Stahl and Eisen 83, No. 29, No. 5, Feb. 28, 1963, pp. 270-281 with certified English Translation. "Weiterentwicklung auf dem Gebiet der Entschwefelung Von Robeisen" Stahl and Eisen 78, No. 13, Jun. 26, 1958, pp. 910-913 together with Certified English Translation thereof. Von Herbert Pohl and Walter Maschlanka "Die Entschwefelung des Roheisens Nach dem Tauchlanzen-Verfahren" Stahl and Eisen 87, Feb. 23, 1967, No. 4, pp. 190-195 together with Certified English translation. C. E. Wood, E. P. Barrett and W. Holbrook Metals Technology, vol. 5, No. 8, Dec. 1938, pp. 1-15. Bernard Trentini et al "IRSID'S Powder Blowing Techniques Applied to Electric Steelmaking", Proceedings of Electric Furnace Conference, 1963, pp. 28-42. B. Trentini, P. Vayssiere, A. De Lavareille & J. Raguin "Powder-Blowing Techniques for Electric Steelmaking" Journal of Metals, Nov. 1964, pp. 885-890. Walter Eichholz and Gerhard Behrendt "Entschwefelung von Thomasroheisen" Stahl und Eisen, issue 31, Aug. 1, 1940, published by Verein Deutscher Eisenhuttenleute, pp. 677-684. Stahl and Eisen, No. 4, Feb. 4, 1971, pp. 152-154; No. 3. Polysius 22-Desulphurization Plants for Pig Iron Using the Dipped Lance Dr.-Ing. H. Klein. Entschiveflung des Stahls, durch Einblasen von pulverformigen Reakionsmitter A. S. Tumarev, A. H. Urazgil dier and L. A. Panjusin. Leitner-Plockinger "Edelstahlerzeugung", pp. 209, 210, 255, 681, and 682.
Patent History
Patent number: RE31676
Type: Grant
Filed: Sep 29, 1982
Date of Patent: Sep 18, 1984
Assignee: Thyssen Aktiengesellschaft vorm August Thyssen-Hutte AG (Duisburg)
Inventor: Walter Meichsner (Krefeld)
Primary Examiner: Joseph J. Rolla
Law Firm: Sprung, Horn, Kramer & Woods
Application Number: 6/427,083