Lance system and method for operating an oxygen lance

Abstract

Lance system (1) for operating an oxygen lance (10) for use in a vessel (90) containing molten steel (94), such as a basic oxygen furnace (BOF) (91), an electric arc furnace (EAF) (92) or a steel ladle (93) containing molten steel (94), the lance system (1) comprising an oxygen line (11), an oxygen regulation valve (12) and an oxygen tank (13), which are configured such that when the regulation valve (12) is opened, oxygen (15) is flowing from the oxygen tank (13) through the oxygen line (11); an oxygen lance (10) comprising a first lance opening (10a) which is connected via the oxygen line (11) and the oxygen regulation valve (12) to the oxygen tank (13); a second lance opening (10b); a substantially tubular body (10c) connecting the first lance opening (10a) and the second lance opening (10b); wherein the oxygen lance (10) is connected to the oxygen line (11) at the first lance opening (10a), and wherein the oxygen lance (10) is configured such that the oxygen (15) flowing through the oxygen line (11) to the first lance opening (10a) is transported from the first lance opening (10a) to the second lance opening (10b), wherein the second lance opening (10b) is configured such that the oxygen (15) exits the oxygen lance (10) at the second lance opening (10b); an induction coil (40), wherein the induction coil (40) is configured to heat the oxygen lance (10) in a region of the second lance opening (10b), such that when the oxygen (15) exits the oxygen lance (10) at the second lance opening (10b), the oxygen lance (10) is ignited and method for operating an oxygen lance (10) of a lance system (1).

Description

[0001] The invention relates to a lance system for operating an oxygen lance for use in a vessel containing molten steel, such as a basic oxygen furnace (BOF), an electric arc furnace (EAF) or a steel ladle containing molten steel and a method for operating an oxygen lance.

[0002] Oxygen lancing is widely used in the production of steel, such as, e.g., during processing of steel in basic oxygen furnaces (BOF) or electric arc furnaces (EAF). Oxygen lances are also widely used to remove steel from various places, such as e.g. to remove frozen (i.e., solidified) steel from a casting channel of a refractory part, such as, e.g., the casting channel of a steel ladle.

[0003] For many applications of such oxygen lances, there is a need to reliably ignite the lance. JPH0825025A discloses a usage of an oxygen lance where an ignition agent is mounted at the tip, which should lead to ignition of the lance when the tip of the lance is pressed against a high-temperature solidified material. JP7317253B1 discloses an oxygen aperture device, where a heat source, such as the molten steel in a nearby tundish, is used to ignite the tip of an oxygen lance.

[0004] It is an object of the invention to provide a lance system which allows reliable ignition of an oxygen lance.

[0005] It is a further object of the invention to provide a lance system which allows an automated or an automatable ignition of an oxygen lance and a reduced or fully eliminated human interaction during ignition of an oxygen lance.

[0006] It is a further object of the invention to provide a lance system which allows safe ignition of an oxygen lance without any hot sources to be used.

[0007] It is a further object of the invention to provide a method for operation of an oxygen lance of such a lance system.

[0008] The object is achieved by a lance system according to claim 1 and a method for operating an oxygen lance of a lance system according to claim 14.

[0009] The core idea of the invention is based on the finding that an oxygen lance can be reliably ignited by an induction coil that heats the oxygen lance in the region where oxygen exits the lance.

[0010] In a first aspect of the invention, the object is achieved by providing a lance system for operating an oxygen lance for use in a vessel containing molten steel, such as a basic oxygen furnace (BOF), an electric arc furnace (EAF) or a steel ladle containing molten steel, the lance system comprising: an oxygen line, an oxygen regulation valve and an oxygen tank, which are configured such that when the regulation valve is opened, oxygen is flowing from the oxygen tank through the oxygen line; an oxygen lance comprising: a first lance opening which is connected via the oxygen line and the oxygen regulation valve to the oxygen tank; a second lance opening; a substantially tubular body connecting the first lance opening and the second lance opening; wherein the oxygen lance is connected to the oxygen line at the first lance opening, and wherein the oxygen lance is configured such that the oxygen flowing through the oxygen line to the first lance opening is transported from the first lance opening to the second lance opening, wherein the second lance opening is configured such that the oxygen exits the oxygen lance at the second lance opening; an induction coil, wherein the induction coil is configured to heat the oxygen lance in a region of the second lance opening such that, when the oxygen exits the oxygen lance at the second lance opening, the oxygen lance is ignited.

[0011] In a second aspect of the invention, the object is achieved by providing a method for operating an oxygen lance of a lance system for use in a vessel containing molten steel, such as a basic oxygen furnace (BOF), an electric arc furnace (EAF) or a ladle containing molten steel, preferably by using a lance system according the first aspect of the invention, the method comprising the steps: A lance providing step where an oxygen lance is provided, the oxygen lance comprising: a first lance opening which is connected via an oxygen line and an oxygen regulation valve to an oxygen tank; a second lance opening; a substantially tubular body connecting the first lance opening and the second lance opening; whereas the oxygen lance is configured such that oxygen provided to the first lance opening is transported from the first lance opening to the second lance opening; An oxygen providing step, where the oxygen regulation valve is opened such that oxygen is provided to the first lance opening of the oxygen lance, such that the oxygen exits the oxygen lance at the second lance opening; An ignition step, where the second lance opening is approached to an induction coil, whereas the induction coil heats the oxygen lance in a region of the second lance opening such that, when the oxygen exits the oxygen lance at the second lance opening, the oxygen lance is ignited; Preferably a burning step, wherein the second lance opening is moved to a positional target, after the oxygen lance is ignited.

[0012] In a third aspect of the invention, the object is achieved by providing a method for operating an oxygen lance of a lance system for use in a vessel containing molten steel, such as a basic oxygen furnace (BOF), an electric arc furnace (EAF) or a ladle containing molten steel, by using a lance system according the first aspect of the invention, the method comprising the steps: A lance system providing step where an oxygen lance system according the first aspect of the invention is provided; An oxygen providing step, where the oxygen regulation valve is opened such that oxygen is provided to the first lance opening of the oxygen lance, such that the oxygen exits the oxygen lance at the second lance opening; An ignition step, where the second lance opening is approached to an induction coil, whereas the induction coil heats the oxygen lance in a region of the second lance opening, such that, when the oxygen exits the oxygen lance at the second lance opening, the oxygen lance is ignited; Preferably a burning step, wherein the second lance opening is moved to a positional target, after the oxygen lance is ignited.

[0013] Preferably, the oxygen lance is made of steel. Preferably, the oxygen lance is a steel pipe. The oxygen lance may be of any suitable dimension. Preferably, the oxygen lance is a 1 / 2" or 3 / 4" steel pipe (e.g., for a 1 / 2" pipe the outer diameter is 21,3 mm, the inner diameter is 16 mm).

[0014] The induction coil may be any coil suitable for heating the oxygen lance in a region of the second lance opening via induction. The coil may be manually operated and operatable, e.g., by connecting the coil windings to a suitable power supply or turning on a suitable power supply, such that an alternating current flows through the coil. The coil is kept in operation until the oxygen lance becomes sufficiently hot in a region of the second lance opening. Preferably the induction coil heats the oxygen lance in a region of the second lance opening to a temperature of above 850 °C, more preferably of above 1000 °C, most preferably of above 1250 °C.

[0015] Preferably, the lance system further comprises a manipulator, such as a robot, for handling the oxygen lance. Preferably, the method further comprises providing a manipulator, such as a robot, for handling the oxygen lance. The manipulator might be a mechanical manipulator operated and operatable by a human or a simple manipulator operated by actuators or alike. The robot might be an industrial robot, preferably an industrial robot with at least 3 axis, more preferably with 6 axis. The robot is preferably configured such, that the robot can pick up a lance from a lance storage. The robot is preferably configured such, that the robot can approach the second lance opening to the induction coil. The robot is preferably configured such, that the robot can move the second lance opening to a positional target, preferably that the robot can move the second lance opening into the casting channel of a steel ladle. The manipulator allows for safe lance handling from a distance, the robot additionally allows a precise handling and a reduction of human interaction in a harmful / dangerous environment.

[0016] Preferably, the oxygen regulation valve is an electrically controllable regulation valve. The electrically controllable regulation valve is configured to vary the flow of oxygen through the oxygen line. Preferably, the electrically controllable regulation valve is an electrically controllable needle valve, since the most precise regulation is achieved in this way.

[0017] Preferably, the induction coil is supplied with an alternating current by an induction coil driver.

[0018] Preferably, the lance system further comprises a pressure gauge. Preferably the method further comprises providing a pressure gauge. Preferably, the pressure gauge is configured to measure the pressure of the oxygen flowing in the oxygen line. This allows to monitor an important process parameter, already during ignition of the lance.

[0019] Preferably, the lance system further comprises a flow meter. Preferably the method further comprises providing a flow meter. Preferably the flow meter is configured to measure the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line. This allows to monitor an important process parameter, already during ignition of the lance.

[0020] Preferably, the lance system further comprises a control unit. Preferably the method further comprises providing a control unit. Preferably, the control unit controls / is configured to control the oxygen regulation valve, preferably the electrically controllable regulation valve. Preferably, the control unit controls / is configured to control the induction coil driver. Preferably, the control unit controls / is configured to control the manipulator. Preferably, the control unit controls / is configured to control the robot. Preferably, the control unit receives / is configured to receive the pressure (p) of the oxygen flowing in the oxygen line from the pressure gauge. Preferably, the control unit receives / is configured to receive the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line from the flow meter.

[0021] Preferably, the control unit receives / is configured to receive the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line from the flow meter, and the control unit controls / is configured to control the oxygen regulation valve, preferably the electrically controllable regulation valve, such that an ignition target for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line is achieved before the oxygen lance is ignited, and whereas the control unit controls / is configured to control the oxygen regulation valve, preferably the electrically controllable regulation valve, such that a burning target for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line is achieved after the oxygen lance is ignited.

[0022] Preferably, the control unit receives / is configured to receive the ignition target for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line before the oxygen lance is ignited. The ignition target is a value to be achieved (thus a target) for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line before the oxygen lance is ignited.

[0023] Preferably, the control unit receives / is configured to receive the burning target for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line after the oxygen lance is ignited. The burning target is a value to be achieved (thus a target) for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line after the oxygen lance is ignited.

[0024] Preferably, the ignition target for the volumetric flow (Qv) is 6 to 24 Nm 3< / h, preferably 12 to 18 Nm 3< / h and / or the ignition target for the mass flow (Qm) is 8 to 32 kg / h, preferably 16 to 24 kg / h.

[0025] Preferably, the burning target for the volumetric flow (Qv) is 50 to 150 Nm 3< / h, preferably 70 to 110 Nm 3< / h and / or the burning target for the mass flow (Qm) is 67 to 200 kg / h, preferably 94 to 147 kg / h.

[0026] Preferably, the control unit is configured (e.g., programmed) to control the manipulator, preferably the robot, such that the second lance opening is approached to the induction coil, the control unit is configured (e.g., programmed) to control the induction coil driver such that the induction coil heats the lance in a region of the second lance opening after the second lance opening was approached to the induction coil, preferably the control unit is configured (e.g., programmed) to control the electrically controllable regulation valve such that the oxygen exits the oxygen lance at the second lance opening, so that the oxygen lance is ignited.

[0027] Preferably, the control unit is configured (e.g., programmed) to control the manipulator, preferably the robot, to move the oxygen lance such that the induction coil heats the oxygen lance in a region of the second lance opening up to a region of at least 0,1 m, preferably at least 0,2 m, from the second lance opening into the direction of the first lance opening. This has the advantage, that the lance shows an increasingly stabilized burning behaviour directly after ignition.

[0028] Preferably, the control unit is configured (e.g., programmed) to control the manipulator, preferably the robot, such that the second lance opening is approached to the induction coil, the control unit is further configured (e.g., programmed) to control the induction coil driver such that the induction coil heats the lance in a region of the second lance opening, preferably the control unit is configured (e.g., programmed) to control the electrically controllable regulation valve such that the oxygen exits the oxygen lance at the second lance opening, so that the oxygen lance is ignited.

[0029] Preferably, the control unit is configured (e.g., programmed) to control the robot such that the second lance opening is moved to a positional target, such as within a casting channel of a steel ladle, after the oxygen lance is ignited.

[0030] Preferably, the positional target is a casting channel of a steel ladle.

[0031] Exemplary embodiments of the invention are explained in more detail by means of illustrations: Fig. 1 shows a schematic representation of the lance system before ignition of a lance. Fig. 2 shows a schematic representation of the lance system after ignition of a lance. Fig. 3 shows a schematic representation of a lance during burning positioned within a casting channel of a steel ladle. Fig. 4 shows a schematic representation of a method for operating an oxygen lance.

[0032] Fig. 1 shows an example of a lance system 1 for operating an oxygen lance 10 for use in a vessel 90 containing molten steel 94, here a steel ladle 93 containing molten steel 94. The lance system 1 here comprises an oxygen line 11, an oxygen regulation valve 12 and an oxygen tank 13, which are configured such that, when the regulation valve 12 is opened, oxygen 15 is flowing from the oxygen tank 13 through the oxygen line 11. Here, an oxygen lance 10 in the form of a steel pipe is present, the oxygen lance 10 comprising a first lance opening 10a which is connected via the oxygen line 11 and the oxygen regulation valve 12 to the oxygen tank 13; a second lance opening 10b; a substantially tubular body 10c connecting the first lance opening 10a and the second lance opening 10b. Here, the oxygen lance 10 is connected to the oxygen line 11 at the first lance opening 10a, and the oxygen lance 10 is configured such that the oxygen 15 flowing through the oxygen line 11 to the first lance opening 10a is transported from the first lance opening 10a to the second lance opening 10b, and the second lance opening 10b is configured such that the oxygen 15 exits the oxygen lance 10 at the second lance opening 10b.

[0033] The lance system 1 further comprises an induction coil 40, which is configured to heat the oxygen lance 10 in a region of the second lance opening 10b such that, when the oxygen 15 exits the oxygen lance 10 at the second lance opening 10b, the oxygen lance 10 is ignited.

[0034] In the example of Fig. 1, further a robot 30 for handling the oxygen lance 10 is present. The robot 30 here is an industrial robot with 6-axis. The robot 30 is configured such, that the robot 30 can move the second lance opening 10b to a positional target 420, preferably such that the robot 30 can move the second lance opening 10b into the casting channel 93a of a steel ladle 93.

[0035] Here, the oxygen regulation valve 12 is an electrically controllable regulation valve 12, especially an electrically controllable needle valve.

[0036] The induction coil 40 of this example is supplied with an alternating current by an induction coil driver 41.

[0037] Here, the lance system 1 further comprises a pressure gauge 17, the pressure gauge 17 is configured to measure the pressure (p) of the oxygen 15 flowing in the oxygen line 11. Additionally, the lance system 1 further comprises a flow meter 18 configured to measure the mass flow (Qm) (in an alternative example the volumetric flow (Qv)) of the oxygen 15 flowing in the oxygen line 11.

[0038] Here, the lance system 1 further comprises a control unit 50 configured to control the oxygen regulation valve 12 (here: the electrically controllable regulation valve 12), the induction coil driver 41, the manipulator 20 and the robot 30. The control unit 50 here is configured to receive the pressure (p) of the oxygen 15 flowing in the oxygen line 11 from the pressure gauge 17 and to receive the mass flow (Qm) (in an alternative example the volumetric flow (Qv)) of the oxygen 15 flowing in the oxygen line 11 from the flow meter 18.

[0039] As the control unit 50 of this example is configured to receive the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen 15 flowing in the oxygen line 11 from the flow meter, the control unit 50 is configured to control the electrically controllable regulation valve 12 such that an ignition target 310 for the mass flow (Qm) (in an alternative example the volumetric flow (Qv)) of the oxygen 15 flowing in the oxygen line 11 is achieved before the oxygen lance 10 is ignited, and whereas the control unit 50 is configured to control the electrically controllable regulation valve 12 such that a burning target 410 for the mass flow (Qm) (in an alternative example the volumetric flow (Qv)) of the oxygen 15 flowing in the oxygen line 11 is achieved after the oxygen lance 10 is ignited.

[0040] The control unit 50 here has received the ignition target 310 (here: 15 Nm 3< / h) for the volumetric flow (Qv) (in an alternative example the mass flow (Qm) - there 20 kg / h) of the oxygen 15 flowing in the oxygen line 11 before the oxygen lance 10 is ignited and has received the burning target 410 (here: 90 Nm 3< / h) for the volumetric flow (Qv) (in an alternative example the mass flow (Qm) - there 120 kg / h) of the oxygen 15 flowing in the oxygen line 11 after the oxygen lance 10 is ignited.

[0041] Here, the control unit 50 is programmed to control the robot 30, such that the second lance opening 10b is approached to the induction coil 40, the control unit 50 is programmed to control the induction coil driver 41 such that the induction coil 40 heats the lance 10 in a region of the second lance opening 10b, the control unit 50 is programmed to control the electrically controllable regulation valve 12 such that the oxygen 15 exits the oxygen lance 10 at the second lance opening 10b, so that the oxygen lance 10 is ignited.

[0042] In this example, the control unit 50 is programmed to control the robot 30, to move the oxygen lance 10 such that the induction coil 40 heats the oxygen lance 10 in a region of the second lance opening 10b up to a region of at least 0,25 m, from the second lance opening 10b into the direction of the first lance opening 10a.

[0043] Here, the control unit 50 is programmed to control the robot 30 such that the second lance opening 10b is moved to a positional target 420, here positioned inside of a casting channel 93a of a steel ladle 93, after the oxygen lance 10 is ignited.

[0044] Fig. 1 shows the lance 10 with it's second lance opening 10b approached to the induction coil 40, which heats the lance 10 in the region of the second lance opening 10b. During this heating the electrically controllable regulation valve 12 is set such that the ignition target 310 is reached.

[0045] Fig. 2 shows the lance system 1 of Fig. 1, except that the lance 10 is already ignited, the electrically controllable regulation valve 12 is set such that the burning target 410 is reached. Furthermore, lance 10 was moved from a position where the second lance opening 10b was approached to the induction coil 40 to a positional target 420 where the second lance opening 10b is within a casting channel 93a of a steel ladle 93.

[0046] Fig. 3 shows a schematic representation of an ignited lance 10 during burning. Here, the second lance opening 10b is positioned within a casting channel 93a of a steel ladle 93. Inside the casting channel 93a is a blockage, due to frozen steel. The lance 10 is used to melt and burn this frozen steel to open the casting channel 93b for operation.

[0047] Fig. 4 shows a schematic representation of a method for operating an oxygen lance 10 of a lance system 1 for use in a vessel 90 containing molten steel 94, such as a basic oxygen furnace (BOF) 91, an electric arc furnace (EAF) 92 or a ladle 93 containing molten steel 94, preferably by using a lance system according to the example of Fig. 1 and 2. The method of this example comprises several steps such as a lance providing step 100, an oxygen providing step 200, an ignition step 300, and a burning step 400.

[0048] In the lance providing step 100, an oxygen lance 10 is provided, the oxygen lance 10 comprising a first lance opening 10a which is connected via an oxygen line 11 and an oxygen regulation valve 12 to an oxygen tank 13; a second lance opening 10b; a substantially tubular body 10c connecting the first lance opening 10a and the second lance opening 10b; whereas the oxygen lance 10 is configured such that oxygen 15 provided to the first lance opening 10a is transported from the first lance opening 10a to the second lance opening 10b.

[0049] In the oxygen providing step 200, the oxygen regulation valve 12 is opened such that oxygen is provided to the first lance opening 10a of the oxygen lance 10, such that the oxygen exits the oxygen lance 10 at the second lance opening 10b.

[0050] In the ignition step 300, the second lance opening 10b is approached to an induction coil 40, whereas the induction coil 40 heats the oxygen lance 10 in a region of the second lance opening 10b such that such that when the oxygen 15 exits the oxygen lance 10 at the second lance opening 10b, the oxygen lance 10 is ignited.

[0051] In the burning step 400, the second lance opening 10b is moved to a positional target 420, after the oxygen lance 10 is ignited. Here the positional target 420 is a casting channel 93a of a steel ladle 93.List of reference numerals and factors:

[0052] 1Lance system 10Oxygen lance 10aFirst lance opening 10bSecond lance opening 10cTubular body 11Oxygen line 12Oxygen regulation valve 13Oxygen tank 15Oxygen 17Pressure gauge 18Flow meter 20Manipulator 30Robot 40Induction coil 41Induction coil driver 50Control unit 90Vessel 91basic oxygen furnace (BOF) 92electric arc furnace (EAF) 93steel ladle 93aCasting channel of steel ladle 94molten steel 100lance providing step 200oxygen providing step 300ignition step 310ignition target for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line 400Burning step 410burning target for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen flowing in the oxygen line 420Positional target Qmmass flow Qvvolumetric flow ppressure

Claims

1. Lance system (1) for operating an oxygen lance (10) for use in a vessel (90) containing molten steel (94), such as a basic oxygen furnace (BOF) (91), an electric arc furnace (EAF) (92) or a steel ladle (93) containing molten steel (94), the lance system (1) comprising: 1.1 an oxygen line (11), an oxygen regulation valve (12) and an oxygen tank (13), which are configured such that when the regulation valve (12) is opened, oxygen (15) is flowing from the oxygen tank (13) through the oxygen line (11); 1.2 an oxygen lance (10) comprising: 1.2.1 a first lance opening (10a) which is connected via the oxygen line (11) and the oxygen regulation valve (12) to the oxygen tank (13); 1.2.2 a second lance opening (10b); 1.2.3 a substantially tubular body (10c) connecting the first lance opening (10a) and the second lance opening (10b); 1.2.4 wherein the oxygen lance (10) is connected to the oxygen line (11) at the first lance opening (10a), and wherein the oxygen lance (10) is configured such that the oxygen (15) flowing through the oxygen line (11) to the first lance opening (10a) is transported from the first lance opening (10a) to the second lance opening (10b), wherein the second lance opening (10b) is configured such that the oxygen (15) exits the oxygen lance (10) at the second lance opening (10b); 1.3 an induction coil (40), wherein the induction coil (40) is configured to heat the oxygen lance (10) in a region of the second lance opening (10b), such that when the oxygen (15) exits the oxygen lance (10) at the second lance opening (10b), the oxygen lance (10) is ignited.

2. Lance system (1) according to claim 1, the lance system (1) further comprises a manipulator (20), such as a robot (30), for handling the oxygen lance (10).

3. Lance system (1) according to any of claims 1 to 2, wherein the oxygen regulation valve (12) is an electrically controllable regulation valve (12).

4. Lance system (1) according to any of claims 1 to 3, wherein the induction coil (40) is supplied with an alternating current by an induction coil driver (41).

5. Lance system (1) according to any of claims 1 to 4, wherein the lance system (1) further comprises a pressure gauge (17) which is configured to measure the pressure (p) of the oxygen (15) flowing in the oxygen line (11).

6. Lance system (1) according to any of claims 1 to 5, wherein the lance system (1) further comprises a flow meter (18) which is configured to measure the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen (15) flowing in the oxygen line (11).

7. Lance system (1) according to any of claims 4 to 6, the lance system (1) further comprises a control unit (50), the control unit (50) is configured to control the oxygen regulation valve (12), preferably the electrically controllable regulation valve (12), the control unit (50) is configured to control the induction coil driver (41), the control unit (50) is configured to control the manipulator (20), preferably the robot (30).

8. Lance system (1) according to claim 7, wherein the control unit (50) is configured to receive the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen (15) flowing in the oxygen line (11) from the flow meter, the control unit (50) is configured to control the oxygen regulation valve (12), preferably the electrically controllable regulation valve (12) such that an ignition target (310) for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen (15) flowing in the oxygen line (11) is achieved before the oxygen lance (10) is ignited, and wherein the control unit (50) is configured to control the oxygen regulation valve (12), preferably the electrically controllable regulation valve (12) such that a burning target (410) for the mass flow (Qm) and / or the volumetric flow (Qv) of the oxygen (15) flowing in the oxygen line (11) is achieved after the oxygen lance (10) is ignited.

9. Lance system (1) according to claim 8, wherein the ignition target (310) for the volumetric flow (Qv) is 6 to 24 Nm3 / h, preferably 12 to 18 Nm3 / h and / or the ignition target (310) for the mass flow (Qm) is 8 to 32 kg / h, preferably 16 to 24 kg / h.

10. Lance system (1) according to any of claims 8 to 9, wherein the burning target (410) for the volumetric flow (Qv) is 50 to 150 Nm3 / h, preferably 70 to 110 Nm3 / h and / or the burning target (410) for the mass flow (Qm) is 67 to 200 kg / h, preferably 94 to 147 kg / h.

11. Lance system (1) according to any of claims 7 to 10, wherein the control unit (50) is configured to control the manipulator (20), preferably the robot (30), such that the second lance opening (10b) is approached to the induction coil (40), the control unit (50) is configured to control the induction coil driver (41) such that the induction coil (40) heats the lance (10) in a region of the second lance opening (10b), preferably the control unit (50) is configured to control the electrically controllable regulation valve (12) such that the oxygen (15) exits the oxygen lance (10) at the second lance opening (10b), so that the oxygen lance (10) is ignited.

12. Lance system (1) according to claim 11, wherein the control unit (50) is configured to control the manipulator (20), preferably the robot (30), such that the oxygen lance (10) is moved such that the induction coil (40) heats the oxygen lance (10) in a region of the second lance opening (10b) up to a region of at least 0,1 m, preferably at least 0,2 m, from the second lance opening (10b) into the direction of the first lance opening (10a).

13. Lance system (1) according to any of claims 7 to 12, wherein the control unit (50) is configured to control the robot (30) such that the second lance opening (10b) is moved to a positional target (420), such as within a casting channel (93a) of a steel ladle (93), after the oxygen lance (10) is ignited.

14. Method for operating an oxygen lance (10) of a lance system (1) for use in a vessel (90) containing molten steel (94), such as a basic oxygen furnace (BOF) (91), an electric arc furnace (EAF) (92) or a ladle (93) containing molten steel (94), preferably by using a lance system according to any of claims 1 to 13, the method comprising the steps: 14.1 A lance providing step (100) where an oxygen lance (10) is provided, the oxygen lance (10) comprising: 14.1.1 a first lance opening (10a) which is connected via an oxygen line (11) and an oxygen regulation valve (12) to an oxygen tank (13); 14.1.2 a second lance opening (10b); 14.1.3 a substantially tubular body (10c) connecting the first lance opening (10a) and the second lance opening (10b); 14.1.4 whereas the oxygen lance (10) is configured such that oxygen (15) provided to the first lance opening (10a) is transported from the first lance opening (10a) to the second lance opening (10b); 14.2 An oxygen providing step (200), where the oxygen regulation valve (12) is opened such that oxygen (15) is provided to the first lance opening (10a) of the oxygen lance (10), such that the oxygen (15) exits the oxygen lance (10) at the second lance opening (10b); 14.3 An ignition step (300), where the second lance opening (10b) is approached to an induction coil (40), whereas the induction coil (40) heats the oxygen lance (10) in a region of the second lance opening (10b), such that when the oxygen (15) exits the oxygen lance (10) at the second lance opening (10b), the oxygen lance (10) is ignited; 14.4 Preferably a burning step (400), wherein the second lance opening (10b) is moved to a positional target (420), after the oxygen lance (10) is ignited.

15. Method according to claim 14, wherein the positional target (420) is a casting channel (93a) of a steel ladle (93).

Images