JPH1161230A - Lance for refining - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove metal stuck to the inner peripheral surface of a refining furnace without damaging the furnace wall. SOLUTION: A lance is provided with a nozzle for refining arranged at the tip part of the lance body, a gas supplying passage for refining connected with the nozzle for refining, nozzles for secondary combustion arranged on the outer peripheral surface of the lance body and an oxygen passage for secondary combustion connected with the nozzles for secondary combustion. The nozzles for secondary combustion are arranged at the position enabling jetting of oxygen for secondary combustion toward the inner peripheral surface of the position (trunnion side T) which is not faced to a discharging hole for contents in a refining furnace. In the height position X at the upper part of the lance A, straight holes 12 are arranged. Except the upper part of the lance A, i.e., in the height positions Y and Z of the lance A, Laval holes 11 having longer reaching distance of the jetting oxygen than that of the straight hole 12, are arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a smelting facility using a lance such as a converter, a vacuum degassing tank, or a container for hot metal or molten steel. The present invention relates to a smelting lance that can efficiently and reliably prevent adhesion to an inner peripheral surface of a furnace, a vacuum degassing tank, a hot metal or a molten steel container, a furnace port, and the like while performing refining.

[0002]

2. Description of the Related Art Refining lances (hereinafter referred to as "lances") are used for refining in a converter, a vacuum degassing tank, a hot metal or molten steel vessel (hereinafter referred to as a "smelting furnace"). For blowing gas such as nitrogen, argon gas or air into molten metal such as hot metal or molten steel.

[0003] For example, a refining reaction in a pure oxygen top-blowing converter proceeds by injecting high-purity oxygen gas onto the liquid surface of molten steel from a lance inserted from a furnace opening of the converter.
In this refining reaction, by blowing oxygen gas, oxygen and molten steel components react violently, and a large amount of converter gas (CO gas) is generated. This converter gas is
It has an active ingredient and sensible heat as fuel and is collected by an exhaust gas recovery device. When the converter gas is guided to the recovery device, a large amount of iron dust passes through the furnace port together with the converter gas, so that high-temperature iron dust adheres to the furnace port and solidifies to form a metal. The metal grows from the furnace opening toward the inside of the converter, and also covers the refractory bricks constituting the furnace wall of the converter. Such bullion is called Behren. If the metal is developed and its thickness exceeds a predetermined value, it becomes difficult to insert scrap, hot metal, etc. from the furnace port, and the flow velocity of the converter gas passing through the furnace port increases. And promotes the growth of the slab attached to the furnace opening.

[0004] Here, a description will be given of the base metal adhering to the inner peripheral surface of the converter. FIG. 22 is a perspective view showing an example of a converter, FIG. 23 is a plan view, and FIG. 24 is a plan view schematically explaining the adhesion of metal in the converter. During refining of molten steel by the converter 1, the metal 6 adhered to the inner peripheral surface of the converter 1 discharges molten steel or steel slag (hereinafter, referred to as “hot water”) after the refining is completed. Since it is washed away by the flow and the pool (hereinafter, referred to as "washing-out phenomenon"), it is worn and removed. In particular, when the furnace body is viewed in the circumferential direction held by the trunnion ring 4, the above-described flushing phenomenon is conspicuous on the inner peripheral surface on the side of the tapping port 2 and the side of the steel slag discharge port 3 of the converter. . Therefore, as shown in FIG.
On the trunnion 5 side (indicated by the symbol T in FIG. 24), which is the axis of the tilt of the converter 1 with less flushing phenomenon, the remaining metal becomes large. In addition, the metal also adheres to the lance C.

[0005] Next, the metal that adheres to the outer peripheral surface of the lance will be examined. The metal that adheres to the outer peripheral surface of the lance does not adhere uniformly in the longitudinal direction of the lance. In addition, the amount of refining,
Depending on the refining conditions, such as the refining time and the amount of oxygen, and the conditions for charging the auxiliary material, the manner of adhesion varies.

As described above, in a normal operation of a converter or the like, the position where the amount of metal adhered on the inner peripheral surface of the furnace body is large and the position where the amount of metal adhered on the outer peripheral surface of the lance is large are determined in the furnace axial direction ( (I.e., the same in the longitudinal direction of the lance). Furthermore, they do not match in the circumferential direction of the furnace body.

As means for solving such a problem relating to the adhesion of the metal, Japanese Patent Application Laid-Open No. 9-3519 discloses a lance for refining comprising the following (hereinafter referred to as "prior art 1").
).

In a multi-tube refining lance having a cooling pipe provided with a cooling water supply passage and a drain passage outside an oxygen pipe having a refining nozzle at an end thereof, an outer peripheral surface of the cooling pipe is provided. A plurality of secondary combustion nozzles capable of injecting oxygen horizontally or downward along the circumferential direction of a plurality of nozzles at a predetermined interval, and a metal ingot capable of injecting oxygen radially around each of the secondary combustion nozzles A refining lance comprising a plurality of melt removal nozzles, and an oxygen passage through which oxygen can be supplied is connected to each of the secondary combustion nozzle and the base metal melt removal nozzle.

[0009] Here, the metal melting and removing nozzle has a structure in which the oxygen injection distance is shorter than that of the secondary combustion nozzle. Further, in the prior art 1, in the embodiment, a position close to the furnace opening of the converter of the lance (hereinafter, referred to as “furnace position”).
Only the metal melt removal nozzle is placed at a position farther from the furnace port than the furnace port position (hereinafter referred to as the “furnace position”).
A lance having a configuration in which both a subsequent combustion nozzle and a metal melt removal nozzle are arranged is disclosed.

According to the prior art 1, while performing refining, both ingots (berene) adhering to the furnace opening of the converter and the inner peripheral surface of the furnace and ingots adhering to the outer peripheral surface of the lance are removed. can do. Further, since the secondary combustion nozzle is not disposed at the furnace port position, it is possible to prevent the metal from being excessively melted and removed at the furnace port position and to extend the life of the refractory bricks constituting the furnace wall of the converter. Has a useful effect.

[0011]

However, the above-mentioned prior art 1 has the following problems. Since oxygen is injected uniformly in the circumferential direction of the converter, the metal that adheres to the furnace wall on the inner peripheral surface of the converter tends to remain excessively on the trunnion side, while the tapping side and the steel slag discharge port On the side, it is removed in excess. Therefore, there is a possibility that the life of the furnace wall on the side where the metal is excessively removed may be shortened. On the other hand, if the removal amount of the metal on the tapping port side and the slag discharge port side is made to be appropriate, the metal on the trunnion side remains excessively, and the opening area of the furnace port and the furnace diameter decrease. in this way,
The metal is ideally attached to the furnace wall at an appropriate thickness in terms of brick protection, and it is disadvantageous in operation if too much is left or too much is removed.

[0012] Because the metal melt removal nozzles are arranged radially around the secondary combustion nozzle, both nozzles
They are arranged at the same position (height) in the furnace axis direction. Therefore, according to the two nozzles arranged at a position on the furnace wall where the amount of metal ingot is large, there is a possibility that the metal removal from the outer surface of the lance may be insufficient.

[0013] Oxygen blown out from the metal melt removal nozzle arranged at the furnace port position may not reach the vicinity of the furnace wall because the rising gas flow at the furnace port position is fast. Therefore, in this case, the metal cannot be removed at the furnace opening position.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and to reduce the adhesion of metal to the lance and the inner wall of the furnace due to the scattered matter generated by the refining of the converter while performing the refining. It is an object of the present invention to provide a smelting lance that can be efficiently removed.

[0015]

According to the first aspect of the present invention,
A refining nozzle provided at the tip of a cylindrical lance body,
A gas supply path for refining connected to the nozzle for refining and a secondary combustion for injecting oxygen for secondary combustion toward an inner peripheral surface of the refining furnace, provided on an outer peripheral surface of the lance main body. In a refining lance including a nozzle and a secondary combustion oxygen path connected to the secondary combustion nozzle, the secondary lance is inserted into a refining furnace having a content discharge port. The combustion nozzle is characterized in that it is disposed at a position where secondary combustion oxygen can be injected toward an inner peripheral surface at a position not facing the content discharge port.

According to a second aspect of the present invention, in the first aspect of the present invention, a straight hole and a Laval hole having a longer injection distance of injected oxygen than the straight hole are used as the secondary combustion nozzle. Characterized in that the Laval hole is provided above the longitudinal direction of the lance body, and the straight hole is provided above the longitudinal direction of the lance body.

According to a third aspect of the present invention, there is provided a refining nozzle provided at a tip of a cylindrical lance main body, a refining gas supply path connected to the refining nozzle, and an outer peripheral surface of the lance main body. A secondary combustion nozzle for injecting secondary combustion oxygen toward an inner peripheral surface of the refining furnace;
In a refining lance having a secondary combustion oxygen path connected to a secondary combustion nozzle, a Laval hole having a straight hole and a Laval hole having a longer injection oxygen injection distance than the straight hole is used as the secondary combustion nozzle, In a state where the smelting lance is inserted into a smelting furnace having a content discharge port, the lance main body, except for the upper part in the longitudinal direction,
The straight hole is at a position where oxygen for secondary combustion can be injected toward the inner peripheral surface at a position facing the content discharge port of the refining furnace, and at a position not facing the content discharge port of the refining furnace. The Laval holes are respectively provided at positions where secondary combustion oxygen can be injected toward the inner peripheral surface, and above the longitudinal direction of the lance main body, a position not opposed to the content discharge port of the refining furnace. The straight hole is provided at a position where oxygen for secondary combustion can be injected toward the inner peripheral surface.

According to a fourth aspect of the present invention, in the first, second or third aspect of the present invention, an oxygen outflow hole having a shorter injection oxygen arrival distance than the straight hole is provided near the secondary combustion nozzle. It is characterized in that it is provided so as to be connected to the oxygen path for secondary combustion.

According to a fifth aspect of the present invention, in the first, second or third aspect of the present invention, an oxygen outlet hole having a shorter injection oxygen arrival distance than the straight hole is connected to the secondary combustion oxygen passage. The lance body is provided between a plurality of the secondary combustion nozzles in the circumferential direction of the outer peripheral surface of the lance main body.

According to a sixth aspect of the present invention, in the fourth aspect of the invention, a plurality of the oxygen outflow holes are circumferentially arranged around the secondary combustion nozzle, and It is characterized in that the respective oxygen injection directions are the same.

According to a seventh aspect of the present invention, in the fourth aspect of the invention, a plurality of the oxygen outflow holes are circumferentially arranged around the secondary combustion nozzle, and Each is characterized in that oxygen is radially injected around the secondary combustion nozzle.

According to the first aspect of the present invention, the secondary combustion nozzle is disposed only at a position not opposed to the content discharge port, that is, only at the trunnion side, and the secondary combustion nozzle is directed toward the inner peripheral surface of the refining furnace on the trunnion side. Since the oxygen for the next combustion is injected, it is possible to efficiently remove the base metal (beren) on the trunnion side having a large amount of applied base metal.

According to the second aspect of the present invention, a Laval hole having the longest oxygen reaching distance is arranged except for the upper part in the longitudinal direction of the lance, and the trunnion-side metal (beren) on the trunnion side, which has a large amount of metal adhesion, is efficiently used. It can be removed well. A straight hole with a shorter oxygen reach than the Laval hole is located above the lance in the longitudinal direction, so that the distance to the inner peripheral surface of the refining furnace is shorter than the furnace position. Secondary combustion is promoted in the vicinity of the furnace wall on the inner peripheral surface of the furnace to prevent excessive melting and removal of the metal at the position of the furnace opening, thereby extending the life of the refractory bricks constituting the furnace wall of the converter. The bullion at the location is properly removed.

According to the third aspect of the present invention, a laval hole is provided on the trunnion side except for a portion above the lance main body, thereby improving the efficiency of removing the base metal (beren) on the trunnion side with a large amount of base metal adhesion. Furthermore, except for the upper part of the lance body, a straight hole having a shorter oxygen reaching distance than the Laval hole is provided at a position facing the contents discharge port to prevent excessive melting and removal of the base metal and to reduce the furnace wall of the converter. It is possible to extend the life of the refractory bricks. In addition, since CO generated during refining is subjected to secondary combustion, it is possible to effectively use a heat source. A straight hole is disposed above the lance in the longitudinal direction. At the furnace port, secondary combustion is promoted near the furnace wall on the inner peripheral surface of the smelting furnace at a position away from the wall, and excessive melting and removal of the ingot are performed. It is possible to extend the life of the refractory bricks constituting the furnace wall of the converter by removing the metal and appropriately remove the metal at the furnace opening.

According to the fourth aspect of the present invention, by providing an oxygen outflow hole in which the injection oxygen has a shorter reach than the straight hole in the vicinity of the secondary combustion nozzle, the efficiency of removing the metal adhering to the lance is improved. improves.

According to the fifth aspect of the present invention, the oxygen outlet hole is provided between the secondary combustion nozzle and the secondary combustion nozzle. Specifically, it is provided on the content discharge port side or between the two secondary combustion nozzles provided on the trunnion side. As described above, if the oxygen outlet holes are arranged between the secondary combustion nozzles in the circumferential direction of the outer peripheral surface of the lance main body, the side nozzle ring (abbreviation: nozzle ring) made of copper casting or the secondary nozzle ring is formed. It can be processed to the same metal as the combustion nozzle ring.

According to the sixth and seventh aspects of the present invention, since the oxygen outflow holes are disposed around the secondary combustion nozzle, the secondary combustion nozzle and the oxygen outflow holes can be machined into the same nozzle tip. In order to make the direction of oxygen injection the same as in the sixth aspect, oxygen outlet holes are arranged in the same cylindrical plane. In order to inject oxygen in the radial direction as in claim 7, the oxygen outlet holes are arranged in the same conical surface in the ridge direction of the cone. Such processing is relatively easy, has low manufacturing costs, and is economically advantageous.

[0028]

Next, an embodiment of the present invention will be described with reference to the drawings. In the embodiment of the present invention, a refining lance for a converter will be described. FIG.
FIG. 15 is a perspective view illustrating the structure of the lance according to the embodiment of the present invention, and FIG. 15 is a perspective view of an auxiliary pipe and a groove illustrating the structure of the lance.

The lance A of the present invention includes a refining gas supply passage 8 inside a cylindrical lance main body 7 and a refining nozzle 9 provided at the tip of the lance main body 7 and connected to the supply passage 8.
And a secondary combustion nozzle 10 provided on the outer peripheral surface of the lance main body 7, and a secondary combustion oxygen path connected to the nozzle 10.

Although not shown, the lance body 7 includes an inner tube,
The cooling water drain pipe is provided outside the inner pipe so as to cover the inner pipe, and the cooling water supply pipe is provided outside the cooling water drain pipe so as to cover the cooling water drain pipe. The cooling water introduced via the cooling water supply pipe 17 passes between the inner pipe and the drain pipe and between the drain pipe and the water supply pipe. Further, inside the lance main body 7, the inner peripheral surface of the inner tube and the outer peripheral surface thereof are in close contact with each other to form the auxiliary tube 1 having a predetermined thickness.
4 is inserted. Therefore, the lance A has a quadruple tube structure. The gas supply path for refining (oxygen supply path in the present embodiment) 8 is formed inside the inner peripheral surface of the auxiliary pipe 14.

The lance main body 7 is provided with a through hole (not shown) which penetrates the inside of the lance main body 7 in the radial direction. Secondary combustion nozzles 10 are provided at openings of the through holes on the outer peripheral surface side of the lance body 7.

As shown in FIG. 15, four grooves 16 are formed in the outer peripheral surface of the auxiliary pipe 14 in the longitudinal direction of the auxiliary pipe 14. Each of the grooves 16 is connected to an opening on the outer peripheral surface side of the through hole. The position of the groove 16 is the position facing the tapping port 2 of the converter, the position facing the steel slag discharge port 3 on the opposite side of the converter 180 ° in the circumferential direction of the converter, and the trunnion side T. , Two positions at 90 ° in the circumferential direction of the converter with respect to the tapping port 2 and the steel slag discharge port 3 (hereinafter referred to as “content discharge port side S”). ) Are set in four places.

In the above-mentioned lance, the structure of the oxygen passage for secondary combustion and the like are shown as one embodiment, and other structures may be used. 1 to 8 are perspective views schematically showing the positions of the secondary combustion nozzles of the lance according to the embodiment of the present invention. Secondary combustion nozzle 1
As 0, a Laval hole 11, a straight hole 12, and an oxygen outflow hole 13 are provided. The Laval hole 11 has the longest reach of the injected oxygen among the three holes. Straight hole 1
No. 2 has a shorter reaching distance of the injected oxygen than the Laval hole 11. The oxygen outflow holes 13 have a shorter reach of the injected oxygen than the straight holes 12. In the drawings, for convenience of explanation, the Laval hole is indicated by a double circle, the straight hole is indicated by a single circle, and the oxygen outlet hole is indicated by a triangle.

[Embodiment 1] As shown in FIG. 1, a Laval hole 11 is formed in a trunnion side T of a lance A,
Are provided in the circumferential direction of the outer peripheral surface of the converter, and inject oxygen for secondary combustion toward the inner peripheral surface on the trunnion side of the converter. It is possible to efficiently remove the metal (beren) on the trunnion side, which has a large amount of metal adhesion.

[Embodiment 2] As shown in FIG. 2, the position above the lance A, that is, the position in the longitudinal direction of the lance A (hereinafter, referred to as the lance A).
A straight hole 12 is provided in the trunnion side T in the “height position” X). At positions other than above the lance A, that is, at the height positions Y and Z of the lance A, the Laval hole 11 is provided on the trunnion side T. A plurality of Laval holes 11 and straight holes 12 are provided in the circumferential direction of the outer peripheral surface of the lance A.

[Third Embodiment] As shown in FIG. 3, a straight hole 12 is provided at the height position X on the trunnion side T. At the height positions Y and Z, a Laval hole 11 is provided on the trunnion side T. Further, at the height positions Y and Z, a straight hole 12 is provided on the content outlet side S. A plurality of Laval holes 11 and straight holes 12 are provided in the circumferential direction of the outer peripheral surface of the lance A.

[Fourth Embodiment] As shown in FIG. 4, a straight hole 12 is provided at the height position X on the trunnion side T. At the height positions Y and Z, a Laval hole 11 is provided on the trunnion side T. Further, between the height positions X and Y and between the positions Y and Z, the oxygen outflow holes 13 are provided in the trunnion side T and the contents discharge port side S.
Is provided. 4 to 6, the Laval hole 1
1. A plurality of straight holes 12 and oxygen outflow holes 13 are provided in the circumferential direction of the outer peripheral surface of the lance A.

As shown in FIG. 5, a straight hole 12 is provided at the height position X on the trunnion side T. At the height positions Y and Z, a Laval hole 11 is provided on the trunnion side T. Further, between the height positions X and Y and between the height positions Y and Z, oxygen outflow holes 13 are provided on the content outlet side S.

As shown in FIG. 6, a straight hole 12 is provided at the height position X on the trunnion side T. At the height positions Y and Z, a laval hole 11 is provided on the trunnion side T.
Are provided, and a straight hole 12 is provided on the content outlet side S. Further, between the height positions Y and Z, oxygen outflow holes 13 are provided on the trunnion side T and the contents discharge port side S.

[Embodiment 5] As shown in FIG. 7, a straight hole 12 is provided on the trunnion side T at the height position X. A plurality of straight holes 12 are provided in the circumferential direction of the outer peripheral surface of the lance A.
An oxygen outflow hole 13 is provided between the two. Laval holes 11 are provided on the trunnion side T at the height positions Y and Z. A plurality of Laval holes 11 are provided in the circumferential direction of the outer peripheral surface of the lance A.
An oxygen outflow hole 13 is provided between the two.

As shown in FIG. 8, at the height position X, a straight hole 12 is provided on the trunnion side T, and an oxygen outlet hole 13 is provided on the content discharge port S side. A plurality of straight holes 12 and oxygen outflow holes 13 are provided in the circumferential direction of the outer peripheral surface of the lance A.
An oxygen outflow hole 13 is provided between and.
At the height positions Y and Z, a Laval hole 11 is provided on the trunnion side T, and an oxygen outflow hole 13 is provided on the contents discharge port S side.
Is provided. Laval hole 11 and oxygen outflow hole 1
A plurality of reference numerals 3 are provided in the circumferential direction of the outer peripheral surface of the lance A, and an oxygen outflow hole 13 is provided between the Laval holes 11.

[Embodiment 6] FIG. 9 is a perspective view of a chip showing the structure of straight holes and oxygen outflow holes, and FIG.
Is a sectional view. The straight holes 12 and the oxygen outflow holes 13 are provided in one chip 15. Around the straight hole 12, a plurality of oxygen outlet holes 13 are arranged in the circumferential direction. Each of the oxygen outlet holes 13 is arranged in the same cylindrical plane. With such a structure,
The oxygen injection directions of the oxygen outlet holes 13 are the same. In addition, the injection direction is the same as the injection direction of the straight hole 12. In FIGS. 9 and 11, O indicates the direction of oxygen injection.

FIG. 11 is a perspective view of a chip showing the structure of Laval holes and oxygen outflow holes, and FIG. 12 is a sectional view.
The Laval hole 11 and the oxygen outlet hole 13 are provided in one chip 15. Around the Laval hole 11,
A plurality of oxygen outlet holes 13 are provided in the circumferential direction. Each of the oxygen outlet holes 13 is arranged in the same cylindrical plane. With such a structure, the oxygen injection directions of the oxygen outlet holes 13 are the same. In addition, the injection direction is the same as the injection direction of the Laval hole 11.

Seventh Embodiment As shown in FIG. 13, each of the oxygen outlet holes 13 may be arranged in the same conical plane in the ridge direction of the cone. With such a structure, the oxygen injection direction of each of the oxygen outlet holes 13 is radially expanded. FIG. 16 shows only the oxygen outlet holes, and FIG.
FIG. 18 is a cross-sectional view showing a chip having only a Laval hole, and FIG. 18 is a chip having only a blind plug. 9 to 13, 16
To 18 can be appropriately selected and used. The position of the secondary combustion nozzle is not limited to the above embodiment, but can be arranged according to the type of the smelting furnace.

[Embodiment 8] In this embodiment, a refining lance for a hot metal container will be described. FIG.
FIG. 19 is a vertical sectional view showing a state of refining by a refining lance for a hot metal container according to Embodiment 8 of the present invention. In FIG. 19, A is a lance of the present invention, 27 is a blast furnace pan, 28 is an injection lance, 29 is hot metal, and 6 is a metal.

Embodiment 9 In this embodiment, a refining lance for a molten steel container will be described. FIG.
FIG. 21 is a vertical sectional view showing a state of refining by a refining lance for a molten steel container according to Embodiment 9 of the present invention. In FIG. 20, A is the lance of the present invention, 30 is a molten steel container, and 31 is
Molten steel 6 is ingot.

[Embodiment 10] In this embodiment, a refining lance for an RH type degassing tank will be described. FIG. 21 is a vertical sectional view showing a state of refining by a refining lance for an RH type degassing tank according to Embodiment 10 of the present invention. In FIG. 21, A is the lance of the present invention, and 32 is RH.
A degassing tank, 33 is a container, 31 is molten steel, and 6 is metal. As shown in FIG. 21, the alloy is introduced from above.
In the RH type degassing tank 32, a reaction of COg + 1 / 2O ₂ = CO ₂ + Q is performed.

[0048]

As described above, according to the present invention, the following useful effects can be obtained.

By disposing the secondary combustion nozzle at a position facing the trunnion side of the refining furnace, oxygen for secondary combustion can be supplied only to the inner peripheral surface of the refining furnace on the trunnion side. It is possible to efficiently remove a large amount of bullion (beren) on the trunnion side.

As the secondary combustion nozzle, a Laval hole, a straight hole, and an oxygen outflow hole having different arrival distances of the injected oxygen are used. By arranging the discharge port side and the furnace port position where the distance to the furnace wall is short, metal removal is performed according to each position.

By providing the oxygen outlet hole, the adhesion of the metal to the lance itself is efficiently prevented, and the life of the lance is extended. The heating efficiency by the secondary combustion of the CO gas is increased, and the refining efficiency is improved.

Since the ingot is removed during the refining operation, the ingot removing operation in which the operation of the refining equipment is stopped is not required, and the production efficiency is improved. The metal does not adhere, which leads to an increase in the amount of tapping water (steel) (the amount of adhesion has been removed in the past), yield is improved, production costs are reduced, and it is economically advantageous.

There is no need to manually remove the ingot, thereby improving working conditions.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 1 of the present invention.

FIG. 2 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 2 of the present invention.

FIG. 3 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 3 of the present invention.

FIG. 4 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 4 of the present invention.

FIG. 5 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 4 of the present invention.

FIG. 6 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 4 of the present invention.

FIG. 7 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 5 of the present invention.

FIG. 8 is a perspective view schematically showing an arrangement position of a secondary combustion nozzle of a lance according to Embodiment 5 of the present invention.

FIG. 9 is a perspective view of a tip showing a structure of straight holes and oxygen outflow holes according to Embodiment 6 of the present invention.

FIG. 10 is a sectional view of a chip showing a structure of straight holes and oxygen outflow holes according to Embodiment 6 of the present invention.

FIG. 11 is a perspective view of a chip showing a structure of Laval holes and oxygen outflow holes according to Embodiment 6 of the present invention.

FIG. 12 is a sectional view of a chip showing a structure of Laval holes and oxygen outflow holes according to Embodiment 6 of the present invention.

FIG. 13 is a sectional view of a chip showing a structure of straight holes and oxygen outflow holes according to Embodiment 7 of the present invention.

FIG. 14 is a perspective view illustrating a structure of a lance according to the embodiment of the present invention.

FIG. 15 is a perspective view of an auxiliary pipe and a groove for explaining a structure of a lance according to the embodiment of the present invention.

FIG. 16 is a sectional view of a chip showing a structure of an oxygen outlet hole.

FIG. 17 is a sectional view of a chip showing a structure of a Laval hole.

FIG. 18 is a sectional view of a chip including only a blind plug.

FIG. 19 is a vertical sectional view showing a state of refining by a refining lance for a hot metal container according to Embodiment 8 of the present invention.

FIG. 20 is a vertical sectional view showing a state of refining by a refining lance for a molten steel container according to Embodiment 9 of the present invention.

FIG. 21 is a vertical sectional view showing a state of refining by a refining lance for an RH type degassing tank according to Embodiment 10 of the present invention.

FIG. 22 is a perspective view showing an example of a converter.

FIG. 23 is a plan view showing an example of a converter.

FIG. 24 is a plan view schematically illustrating the adhesion of the metal in the converter.

[Explanation of symbols]

 A: Lance of the present invention C: Lance T: Trunnion side S: Contents discharge port O: Secondary combustion oxygen injection direction 1: Converter 2: Steel tapping port 3: Steel slag discharge port 4: Trunnion ring 5 : Trunnion 6: Ingot 7: Lance body 8: Refining gas supply passage 9: Refining nozzle 10: Secondary combustion nozzle 11: Laval hole 12: Straight hole 13: Oxygen outflow hole 14: Auxiliary tube 15: Chip 16 : Groove 17: cooling water supply pipe 27: blast furnace pot 28: injection lance 29: hot metal 30: molten steel vessel 31: molten steel 32: RH degassing tank 33: vessel

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Hiji 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Inside Nihon Kokan Co., Ltd. (72) Inventor Taku Ogawa 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd.

Claims (7)

[Claims] 1. A refining nozzle provided at a tip of a cylindrical lance main body, a refining gas supply path connected to the refining nozzle, and the refining furnace provided on an outer peripheral surface of the lance main body. A refining lance comprising: a secondary combustion nozzle for injecting secondary combustion oxygen toward the inner peripheral surface of the secondary combustion nozzle; and a secondary combustion oxygen passage connected to the secondary combustion nozzle. In a state where the smelting lance is inserted into a smelting furnace having an outlet, the secondary combustion nozzle is
2 toward the inner peripheral surface at a position not facing the content discharge port
A refining lance, which is provided at a position where oxygen for the next combustion can be injected. 2. As the secondary combustion nozzle, a straight hole and a Laval hole having a longer distance of injected oxygen than the straight hole are used, and the Laval hole is connected to the lance except for an upper portion in a longitudinal direction of the lance body. 2. The refining lance according to claim 1, wherein the straight holes are provided above the main body in the longitudinal direction. 3. A refining nozzle provided at a tip of a cylindrical lance body, a refining gas supply path connected to the refining nozzle, and the refining furnace provided on an outer peripheral surface of the lance body. A refining lance comprising: a secondary combustion nozzle for injecting secondary combustion oxygen toward the inner peripheral surface of the secondary combustion nozzle; and a secondary combustion oxygen path connected to the secondary combustion nozzle. As the next combustion nozzle, a straight hole and a Laval hole having a longer injection oxygen arrival distance than the straight hole are used, and in a state where the refining lance is inserted into a refining furnace having a content discharge port, the lance body is Except for the upper part in the longitudinal direction, the straight hole is located at a position where oxygen for secondary combustion can be injected toward the inner peripheral surface at a position facing the content discharge port of the refining furnace, and Content outlet The Laval hole is located at a position where oxygen for secondary combustion can be injected toward the inner peripheral surface at a position not opposed to
Each of the straight holes is provided at a position above the lance main body in the longitudinal direction, at a position where the secondary combustion oxygen can be injected toward the inner peripheral surface at a position not facing the content discharge port of the refining furnace. A smelting lance characterized by being made. 4. An oxygen outlet hole having a shorter injection oxygen arrival distance than the straight hole is provided near the secondary combustion nozzle and connected to the secondary combustion oxygen path. 4. The refining lance according to 2, 3 or 4. 5. An oxygen outflow hole having a shorter injection oxygen arrival distance than the straight hole is connected to the secondary combustion oxygen passage, and a plurality of the secondary combustions are provided in a circumferential direction of an outer peripheral surface of the lance main body. 4. The refining lance according to claim 1, wherein the lance is provided between nozzles. 6. A plurality of oxygen outlet holes are circumferentially provided around the secondary combustion nozzle, and the oxygen injection direction of each of the oxygen outlet holes is the same.
Refining lance as described. 7. A plurality of the oxygen outlet holes are circumferentially arranged around the secondary combustion nozzle, and each of the oxygen outlet holes radially surrounds the secondary combustion nozzle. The refining lance according to claim 4, wherein the lance is injected.