EP2767598A1 - Method for operating an oxygen blowing lance in a metallurgical vessel and measuring system for determining measuring signals used for the same - Google Patents

Abstract

The method comprises: continuously detecting and measuring an inlet pressure (P 0 t) and/or an inlet temperature (T 0 t) of gas (8) at a supersonic nozzle, an oscillation amplitude and/or a vibrational frequency of a gas blowing lance (2), an ignition timing in an oxygen-blowing process and/or a local point of ignition in the oxygen-blowing process by detectors or sensors arranged in a region of a lance head (4) during the operation of the lance; and controlling the operation of the lance based on a measurement signal provided to an evaluation and/or process control unit. The method comprises: continuously detecting and measuring an inlet pressure (P 0 t) and/or an inlet temperature (T 0 t) of gas (8) at a supersonic nozzle, an oscillation amplitude and/or a vibrational frequency of a gas blowing lance (2), an ignition timing in an oxygen-blowing process and/or a local point of ignition in the oxygen-blowing process by detectors or sensors arranged in a region of a lance head (4) during the operation of the lance; and controlling the operation of the lance based on a measurement signal provided to an evaluation and/or process control unit. One of the sensors in the region of the lance head: is a pressure sensor that detects and measures the inlet pressure of the gas at the input of the supersonic nozzle; is a temperature sensor that detects and measures the inlet temperature of the gas at the input of the supersonic nozzle; is a vibration sensor that detects and measures the oscillation amplitude and/or the vibrational frequency of the gas blowing lance; and is a light sensor such as charge coupled device or complementary metal oxide sensor that detects and measures the ignition timing in the oxygen-blowing process and/or the local point of ignition in the oxygen-blowing process. A supply pressure of the gas is detected and measured in a gas supply station. The supersonic nozzle has multiples holes each of which is provided with one detector or sensor. The measurement signal from the detectors or sensors are transmitted to the evaluation and/or process control unit through a cable or wirelessly using a radio module arranged in the lance. An electrical energy is provided to the detectors or sensors by an energy harvesting module. An independent claim is included for a system for measuring a measurement signal during operation of a gas blowing lance in a metallurgical vessel.

Description

The invention is directed to a method for operating a blowgun blowing a gas, in particular oxygen blowing lance, in a metallurgical vessel, wherein the preferably replaceable lance head of the lance has at least one supersonic nozzle. Furthermore, the invention is directed to a measuring system for determining the operation of a blowing gas blowing lance, in particular oxygen blowing, in a metallurgical vessel used for process control measurement signals, the measuring system a lance, preferably oxygen blowing lance, with a at least one supersonic nozzle having, preferably interchangeable lance head and comprises an evaluation and / or process control unit receiving and processing the measurement signals.

In steelmaking, in certain processes, such as the Basic Oxygen Furnace (BOF) or Argon Oxygen Decarburization (AOD) process, there is a molten metal in a metallurgical vessel with a gas, especially with oxygen (O ₂ ) or nitrogen (N ₂ ) to flow. For this purpose, a blow lance is typically retracted from above into the metallurgical vessel and from this the gas is blown onto the molten metal.
Also in the field of melting scrap in an electric arc furnace, ie an electric arc furnace (EAF), gas can be blown onto the melt. Inflation of gas is usually carried out in at least the following metallurgical units: BOF converters, AOD converters, burners and injector nozzles for an electric arc furnace (EAF) or CONARC (CON = Arcing) furnace, burners and injector nozzles a reduction furnace (SAF Submerge Arc Furnace) and nozzles for Vacuum treatment plants such as VOD (Vacuum Oxygen Decarburization) - or RH (Ruhrstahl-Heraeus) plants. During steelmaking in the BOF converter, the oxygen is blown onto the metal bath with the help of the lance. The lance head is typically 1.4 to 3 m away from the melt surface. In such a lance head there are usually a plurality of convergent-divergent nozzles arranged at predetermined angles which accelerate the gas to supersonic speed. The convergent-divergent nozzles are called supersonic nozzles or Laval nozzles. From these supersonic nozzles, the gas typically exits at about twice the speed of sound and with a high momentum and then strikes the molten metal. In the molten metal an oscillating Blemmulde is generated and the inflated gas ensures an intensive decarburization reaction. As a result of the ascending gaseous reaction products, a foamed slag is formed on the molten metal.

The geometry of a Laval nozzle or a supersonic nozzle can according to the isentropic Stromfadentheorie only for a single value - namely their ideal operating point or design point - with respect to the inlet pressure p ₀ and the inlet temperature T _{0 of} the supersonic nozzle, and the static Counterpressure p _{A be designed} in the metallurgical vessel. The inlet pressure p ₀ is therefore also in this ideal operating point as a design pressure and the inlet temperature T ₀ is referred to in this ideal operating point as the design temperature. Only when the supersonic nozzle is operated at its ideal operating point, the expanded gas flow is firmly against the nozzle wall until it leaves the nozzle and acceleration of the gas to supersonic velocity is achieved. However, as soon as the actual nozzle flow deviates from the ideal design state or the ideal operating point, inside and outside of the nozzle complex pattern of disturbance (diamond wave pattern) in the form of expansion waves or compression shocks, which can lead to wear of the nozzle edge and which lead to an early replacement of the beam lead from the nozzle wall. With a detachment of the cold gas jet from the nozzle wall, a recirculation area is created, via which hot converter gas reaches the nozzle wall, whereby the nozzle wear then begins. In order to reduce or avoid this nozzle wear, the supersonic nozzle must therefore be operated at its operating point as far as possible.

At the tip of a lance, there is a replaceable lance head, which, depending on the application, includes several convergent-divergent supersonic nozzles or Laval nozzles to accelerate the gas to supersonic speed. Such a lance head can be used, inter alia, in the following metallurgical vessels or aggregates: in BOF and AOD converters, in SIS (Siemag Injection System) injectors for electric arc furnaces (EAF), in reduction furnaces (SAF) and vacuum systems (RH, VOD ).

The geometry of a supersonic nozzle or Laval nozzle, both with respect to the immediate inlet pressure p ₀ , the design pressure of the respective supersonic nozzle, and the inlet temperature T ₀ , the respective design temperature of a supersonic nozzle, exclusively to an optimum operating point of the respective supersonic nozzle at a static back pressure p _{A are designed} in the respective metallurgical vessel or aggregate. Only when the two process variables design pressure / inlet pressure and inlet temperature / design temperature are maintained in converter operation, a supersonic nozzle or Laval nozzle operates at its optimum operating point and the nozzle only slightly wears. Usually, the pilot pressure p _vs and the volume flow of the gas are measured in practical operation on a valve station providing the gas for the lance. These sizes are usually used to design the ultrasonic nozzle. Thus, the pressure loss Δp _verl from the valve station via the pipes and pressure hoses including the entire lance is estimated to determine the inlet pressure p ₀ using the equation p ₀ = p _vs - Δp _verl . The exact pressure loss Δp _verl is theoretically difficult to determine because this one Compressible pressure loss calculation over all components under consideration of the exact routing is required. For this reason, the necessary process variables p ₀ , T ₀ and p _{A are} always known only as approximate values for the nozzle design. Whether the respective ultrasonic nozzle or Laval nozzle actually works in practical steelworks operation at the design point or ideal operating point is uncertain. But lance durability and process stability are worsening.

Furthermore, during the blowing process, the oxygen jet emerging from a lance ignites upon contact with molten pig iron. Since the converter or the respective metallurgical vessel is filled not only with pig iron, but frequently also with coolant such as steel scrap, the oxygen jet emerging from the lance can also be thrown back by steel scrap whose temperature for ignition is not sufficiently high. Very often, the combustion of oxygen does not start immediately with the start of the blowing process. However, it is very important to know the exact time of ignition because the start of the associated decarburization reaction of the respective molten metal bath is decisive for the process control. The ignition timing may also be different for each nozzle of a multi-hole lance, depending on the location of the scrap and the position of the molten pig iron. Here, a differentiated knowledge of the location and time of ignition would allow a correspondingly accurate differentiation between used and unused oxygen.

Finally, forms a melt-slag emulsion in the conventional blowing processes in the converter or metallurgical vessel. The decarburization reaction enormously increases the volume of the slag, which can result in slag ejection, resulting in an increase in production costs and the risk of failure. In addition, during the blowing process, the slag and the molten metal, in particular liquid steel, adhere to the usually water-cooled blowing lance. Such Extensions to a lance are undesirable and must be removed because this undesirably increases the overall mass of the lance and can partially obstruct the apertures of the ultrasonic nozzles.

From the WO 2012/136698 A1 a method for operating an oxygen blowing lance in a metallurgical vessel is known, in which by means of a self-sufficient measuring device that performs without external leads or leads a pressure measurement and / or a temperature measurement over time resolved and stores the corresponding measured values, the pressure and the temperature measured at the entrance of a supersonic nozzle of a lance. Such a self-contained measuring device, also referred to as a "data logger", is inserted into the lance head, then measures the pressure and / or the temperature over its (battery) life and stores this data. The self-sufficient measuring device is then removed from the Blas lanzenkopf and with the help of the read out measurement data, a calibration curve is created. On the basis of this calibration curve, the operation of the then self-sufficient measuring device no longer having oxygen blowing lance is controlled. The disadvantage of using data loggers is that the pressure loss Ap get _engaged that during operation each adjusting inlet pressure p _{0 t} and each adjusting for the ongoing operation inlet temperature T _{0 t} can be only subsequently determined after the lance was removed. A continuous current detection of the inlet _pressure p _0t and the inlet _temperature T _0t during the blowing process does not take place, so that it is not ensured that the ultrasonic nozzle of the lance is operated during operation at its ideal operating point.

Furthermore, it is known from practice to detect oscillations of the lance during operation in the metallurgical vessel by means of conventional vibration transducers arranged on the lance carriage of a lance. From the measurement signals obtained in this way, conclusions can be drawn about the extent of slag formation in the metallurgical vessel and the inclination for slag ejection. The vibration measurements are carried out on the lance carriage, since the vibration sensors are thermally protected there and a lance change can take place regardless of the sensor. The disadvantage of this solution is that the vibrations measured at the lance carriage are significantly lower than the vibrations at the lance tip that are most significantly influenced by the slag formation and can be influenced by process-independent variables. Thus, the measurement signals obtained give the conditions in the area of the Blaslanzenspitze only inaccurate again. In addition, in measurements that are performed above the lance dome, the deflections of the lance are not optimally detected. Finally, there is a risk in the vicinity of the Blaslanzendoms arranged probes that they are wearing out and damaged by the heat acting here and the dust load acting here.

From the WO 2011/151143 A2 It is known, with the aid of a CCD sensors or photodiodes having camera in the gap between the converter mouth and the hood to determine the course of the radiation intensity over time and the time at which a predetermined radiation intensity or a predetermined increase in the radiation intensity is achieved as Time of ignition of the exiting from the lance oxygen jet to determine. This method for determining the time of ignition in inflation with observation of the light emissions of the resulting focal point from the ignition on the one hand has the disadvantage that due to the strong smoke after ignition only indirectly via the radiation of this smoke information about the ignition can be obtained. This limits the reliability of the measurement result. In addition, a differentiated detection of the ignition of individual, which in a multi-hole nozzle usually five to six exiting oxygen jets, not possible.

The invention has for its object to provide a solution that provides a continuous detection of blowing during operation of a gas blowing lance, In particular oxygen blowing lance, operating parameter measuring signals used in a metallurgical vessel for process control allows.

In a method of the type described in more detail, this object is achieved in that by means of at least one lance in the supersonic nozzle arranged detector or sensor during operation of the lance, especially during a blowing process, preferably Sauerstoffblasprozesses, especially continuously, in the lance head of the inlet pressure p _0t and / or the inlet _temperature T _{0t of} the gas at the at least one supersonic _nozzle and / or the oscillation amplitude A and / or the oscillation frequency ω of the lance and / or the ignition timing of the ignition in the oxygen blowing process and / or the location of the ignition detected in the oxygen blowing process and / or is measured and / or the obtained during the operation of the lance of a connected to the at least one detector or sensor evaluation and / or process control unit preferably supplied online and the Steuerun g the operation of the lance is / are provided.

Likewise, the above object is achieved in a measuring system of the type described in more detail by the fact that at least one detector or sensor is arranged in the lance head in the region of the at least one supersonic nozzle, which is in line communication with the evaluation and / or process control unit and during the Operating the lance, in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head, the inlet _pressure p _0t and / or the inlet _temperature T _{0t of} the gas at the at least one supersonic _nozzle and / or the oscillation amplitude A and / or the oscillation frequency ω of the lance and / or the ignition timing of the ignition during the oxygen blowing process and / or the location of the ignition in the oxygen blowing detected and / or measures and the one or more obtained measuring signal (s) during operation of the blowing lance to the at least one detector or sensor connected evaluation and / or process control unit preferably online feeds and provides for controlling the operation of the lance.

The invention is therefore based in its core on arranging in the head of the lance one or more detector (s) and / or sensor (s), which during operation, i. In particular, during the gas Ausblasenden state, the lance in their position in the metallurgical vessel working or operating position metrologically record operating parameters and continuously supply the obtained measurement signals during operation of an evaluation and / or process control unit and provide for controlling the operation of the lance. The measurement signals currently obtained, in each case the operating state with respect to the respective operating parameter, can then be used directly for process control during ongoing operation of the blowing lance.

According to one aspect of the invention, in this way with at least one detector and / or sensor, the current inlet _pressure p _{o of} the gas at the entrance of the at least one supersonic nozzle of the lance is detected and / or measured. According to a second aspect of the invention, by means of at least one detector or sensor during the blowing process, in particular continuously in the lance head, the inlet _temperature T _{0t of} the gas at the entrance of the at least one supersonic nozzle of the lance is detected and / or measured.

These operating parameter measuring signals determined in the first aspect and / or the second aspect of the invention are then fed directly to an evaluation and / or process control unit, preferably online, and provided for process control of the operation of the blowing lance. This makes it possible, for example, to regulate the adaptation of the valve pressure p _vs the current in the lance head at the entrance of a supersonic _nozzle adjusting inlet _pressure p _0t and set so that it the design _pressure p ₀ at least substantially and / or approximately, so with a possibly small Deviation, equivalent. It is thus possible in this way by means of the invention, a supersonic nozzle - and upon provision of a detector or sensor at the entrance of each supersonic or Laval nozzle of a lance - all supersonic nozzles always at least almost in their design state (design point), ie in or on operate at their ideal operating point. This results in stable process conditions for the gas bubbles, in particular oxygen bubbles, which leads to a significantly higher service life and service life of the preferably replaceable lance head. Continuous detection of the inlet _pressure p _0t and the inlet _temperature T _0t during a blowing process thus enables dynamic adjustment of the pressure p _vs at the valve station during the blowing process, thus operating the lance head at its design point and minimizing nozzle wear can.

_{According to} the present invention, the respectively current entry _pressure p _o and the respective current entry _temperature T _{o are measured} inside the lance, ie in the lance head, during the blowing process. This time-dependent pressure and temperature measurement takes place with the aid of detectors and / or sensors. The measurement data is transmitted via a cable or wirelessly to a connected evaluation and / or process control unit, for example a PC. The energy supply of the detectors and / or sensors can be done by the cable or a battery or by means of an energy harvesting module.

In the lance or directly in the lance head pressure and possibly temperature sensors for determining the current inlet pressure p _0t and the current inlet _temperature T _{0t of} the oxygen or blown gas are thus installed in the lance according to these first two aspects of the invention. Simultaneously with the pressure measurement (s) in the lance or in the lance head, the pressure or admission pressure p _vs at the valve station supplying the blowing gas or the oxygen should be measured. This then allows an online calculation of the pressure loss Δp _verl = p _vs - p _0t and a check of the Deviation of the current inlet _pressure p _0t and the current inlet _temperature T _{0t of} the blown gas or the oxygen from the corresponding design _variables of the respective supersonic nozzle design pressure p ₀ and design temperature T ₀ during the blowing process. In this way, the upstream pressure p _vs at the valve station can be adjusted so that at the entrance of one or all supersonic nozzle (s) or Laval nozzle (s) of the lance there is an inlet _pressure p _0t , which corresponds to the design _pressure p ₀ . In this case, lance head wear is minimized. The size T _0t is not necessary for the actual operation, but the design _temperature T _{0 is} required as a theoretical design size in the nozzle design. The static pressure p _A in the metallurgical vessel can not be determined in this way. For the nozzle design, however, it plays only a minor role, since the pressure p _A differs only slightly from the ambient pressure of 1.01 bar. The measured data, ie the determined operating parameter measurement signals, can be transmitted by a cable or wirelessly, the latter for example by means of a radio module installed in the lance, to an evaluation and / or process control unit, for example a computer, in particular a PC Available. The process variables inlet pressure p ₀ and inlet temperature T ₀ directly at the Laval nozzle and the static (counter) pressure p _A in the metallurgical vessel necessary for the correct theoretical design of a supersonic nozzle according to the isentropic streamline theory can now be achieved with the method according to the invention and the measuring system according to the invention continuously capture as each current time-dependent size. These quantities p _0t and T _0t can be continuously measured during the blowing process by means of the detectors and / or sensors arranged in the lance head. The static pressure p _A in the metallurgical vessel plays only a minor role in the correct design and thus the regulation of the operation of the ultrasonic nozzle (s) in or at its ideal operating point, since it usually fluctuates only moderately around the ambient pressure (1.01 bar ± 0.2 bar). If the pressure p _vs at the valve station is also measured continuously, the pressure loss can Δp _verl between the valve station and the entry of the gas into the lance head are also continuously determined during the blowing process.

In particular for the realization of the first two aspects of the invention set forth above, the method according to the invention is characterized in that by means of at least one pressure sensor arranged in the lance head in the region of the at least one supersonic nozzle during operation of the lance, in particular during a blowing process, preferably oxygen blowing process , in particular continuously, in the lance head of the inlet _pressure p _{0t of} the gas at the entrance of the at least one supersonic _{nozzle is} detected and / or measured, and in particular characterized in that by means of at least one arranged in the lance head in the region of the at least one supersonic nozzle temperature sensor during operation of the lance, in particular During a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head the inlet _temperature T _{0t of} the gas at the entrance of the at least one supersonic _{nozzle is} detected u nd / or measured.

In this case, it is particularly expedient if, at the same time, in particular continuously, the supply pressure p _{vs of} the gas is detected and / or measured at a gas supply station arranged at a distance from the at least one supersonic nozzle, as the invention also envisages.

In the same way, the measurement system according to the invention is characterized in that at least one pressure sensor is arranged in the lance head in the region of the at least one supersonic nozzle, which is in line communication with the evaluation and / or process control unit and during operation of the lance, in particular during a blowing process, preferably oxygen blowing process, in particular continuously, detects and / or measures the inlet _pressure p _{0t of} the gas at the entrance of the at least one supersonic _nozzle in the lance head and the one or more obtained (s) During operation of the lance, the measuring signal (s) preferably feeds online to the evaluation and / or process control unit connected to the at least one pressure sensor and provides for controlling the operation of the lance and / or at least one temperature sensor in the lance head in the region of the at least one supersonic nozzle is arranged, which is in line with the evaluation and / or process control unit and during operation of the lance, in particular during a blowing process, preferably Sauerstoffblasprozesses, in particular continuously, detected in the lance head, the inlet _temperature T _{0t of} the gas at the entrance of the at least one supersonic nozzle and / or measures and / or during the operation of the blowing lance the evaluation signal (s) obtained during the operation of the blowing lance are preferably fed online to the evaluation and / or process control unit connected to the at least one temperature sensor and to control the operation of the blower ze.
According to a third aspect of the invention, it is provided that the oscillation amplitude A and / or the oscillation frequency ω of the lance, in particular the oxygen lance, is detected and measured by means of at least one oscillation sensor installed directly in the lance head during operation of the lance. By measuring by means arranged in the lance head detectors and / or sensors is a reliable, maintenance-free and efficient vibration measurement of the lance in the metallurgical vessel, in particular converter, to detect the slag rise and a possible slag ejection and verbierungen the lance possible. It is thus possible to measure the vibrations of the lance, in particular oxygen blowing lance or BOF lance, with a sensor arranged within the lance. In this case, the measurement in the lance head also takes place at a location close to the mouth as possible, ie in this sense "deep" point of the lance, resulting in a high and compared to the prior art higher significance of the measurement signals. The measurement is preferably carried out by means of a wireless sensor (detector (s) and / or sensor (s)), but also a wired or wired arrangement is possible. The latter is However, associated with the problem that in case of damage to the lower lance part, ie the lance head above the sensors formed from the detectors and / or sensors, the leads and possibly the sensor must be renewed consuming. Even with the vibration sensors, the power supply of the wireless sensor can be done using batteries, rechargeable batteries or an energy harvesting module.

To realize this third aspect of the present invention, this is characterized in that by means of at least one vibration sensor arranged in the lance head in the region of the at least one supersonic nozzle during operation of the lance, in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head, the oscillation amplitude A. and / or the oscillation frequency ω of the lance is detected and / or measured.

In the same way, it is provided in an embodiment of the measuring system that at least one vibration sensor is arranged in the lance head in the area of the at least one supersonic nozzle, which is in line communication with the evaluation and / or process control unit and during the operation of the lance, in particular during a blowing process , Preferably oxygen blowing process, in particular continuously, in the lance head, the oscillation amplitude A and / or the oscillation frequency ω of the blowing lance detected and / or measures and the one or more obtained (s) measurement signal (s) during operation of the lance of the connected to the at least one vibration sensor Evaluation and / or process control unit preferably feeds online and provides for controlling the operation of the lance.

By means of the vibration sensors arranged in the lance head for determining the oscillation amplitude A and / or the oscillation frequency ω of a gas blowing lance, in particular an oxygen blowing lance, is a continuous measurement the amplitude and / or the frequency of the vibrations and, consequently, a monitoring of the slag height in the converter or metallurgical vessel possible. At a low slag height, the frequency spectrum is dominated by harmonic natural vibrations of the lance. At a high slag level, the lance is enveloped by the slag. This creates and increases a caused by the slag stochastic component of the vibrations. The formation of the decay at the lance tip also changes their mass. By measuring natural frequencies, the amount of adhering slag or steel can be estimated and an early decision made regarding a lance change. The measured oscillation amplitudes A and / or oscillation frequencies ω are also transmitted in particular wirelessly, in particular by radio, to the evaluation and / or control unit, in particular a computer, preferably a PC, which is operable by the operating personnel. In this case, at least one radio module is then assigned to the respective vibration sensor or the vibration sensors and connected to this or this.

According to a fourth aspect, photodiodes, photodetectors or light sensors, in particular CCD (Charge Coupled Device) sensors or CMOS (Complementary Metal Oxide Semiconductors) sensors are arranged within the lance head, which during a blowing process in the lance head in the ignition of the Oxygen rays detect the occurring optical emissions. Thus, it is possible to detect the time of ignition of a Sauerstoffblaslanze promptly, wherein the photodiode or the at least one optical sensor or detector is disposed within the lance that caused by the ignition of the oxygen rays optical emissions of the focal spot from the sensor within the Blowgun can be detected. The measurement signals determined in this case can then be further processed in the assigned evaluation and / or process control unit. Also in this case, the measurement signal and thus data transmission takes place by a cable or wirelessly by radio. Likewise, the power supply of wireless optical sensors with the help of batteries, batteries or an energy harvesting module is possible.

Immediately in the lance head are the light sensors (CCD sensors, CMOS sensors) or such sensors or diodes or detectors having camera installed to determine the timing of the ignition in the oxygen blowing process. In this case, it is provided to arrange one or more light sensors in the interior of the lance, preferably in the lance head, in order to be able to determine the exact time of the ignition. The optical emission caused when the oxygen beams are ignited is detected by the sensor or the sensors within the lance in the lance head and the determined measurement signals and associated information are conducted to the evaluation and / or control unit, in particular a computer or PC, with the aid of a cable or wirelessly transmitted.

In order to achieve the abovementioned fourth aspect of the invention, the method is characterized in that by means of at least one in the lance head in the region of the at least one supersonic nozzle arranged light sensor, in particular CCD or CMOS sensor, or at least one camera equipped therewith during operation the lance, in particular during a blowing process, preferably Sauerstoffblasprozesses, in the lance head, the (n) occurring when an ignition of the oxygen rays optical (s) emission (s) is / are detected. It is likewise provided for this purpose in an embodiment of the measuring system that at least one light sensor, in particular a CCD or CMOS sensor, or at least one camera equipped therewith is arranged in the lance head in the region of the at least one supersonic nozzle, which line is connected to the evaluation and / or process control unit is in communication and during operation of the lance, in particular during a blowing process, preferably Sauerstoffblasprozesses, in the lance head, the occurring at an ignition of the oxygen jets optical (n) emission (s) detected and / or measures and / or during the operation of the blowing lance the one or more of the obtained (n) measuring signal (e) preferably the online connected to the at least one light sensor, in particular CCD or CMOS sensor, or the at least one camera evaluation and / or process control unit and provides for controlling the operation of the lance.

With the embodiment according to the invention according to the fourth aspect, an accurate determination of the ignition time can be carried out, this also differentiated according to the individual oxygen jets in each case a supersonic nozzle of a Mehrlochblaslanze associated sensor / detector.

A fifth aspect of the invention is directed to detecting and / or measuring the location of ignition in the oxygen blowing process. In this regard, light sensors, in particular CCD or CMOS sensors or detectors, photodiodes or photodetectors or a camera equipped therewith are to be arranged directly in the lance head whose optically receiving sensor surfaces are optically aligned through an orifice of the lance and, in particular, the orifice of an associated supersonic nozzle , The light sensors thus installed in the lance head serve to determine the location of the ignition during the oxygen blowing process. When using multiple directional optical sensors or the use of a camera can be next to the ignition so that also determine commonly used Mehrlochblaslanzen the location of the ignition. Since usually a lance head contains several supersonic nozzles, a light sensor can be assigned to a nozzle. In this way, there is the possibility of a differentiated detection of the ignition of the oxygen jets, since upon striking an oxygen jet to liquid pig iron, a focal spot is formed, while incidence of the focal spot on scrap no focal spot is formed, so that the respective detected areas with respect to their optical emission (s ). The advantage of the installation inside the lance is that the view opening of the camera or the Sensors are kept free by flushing with oxygen. The measurement signals obtained can then in turn be wired or transmitted by radio to the evaluation and / or control unit, in particular a computer or PC and used there for process control. This fifth aspect of the invention thus consists in detecting the ignition location of the oxygen jet by arranging an optical sensor or detector within a lance in such a way that it can detect the optical emissions of the focal spot within the lance caused by the ignition of the oxygen beams the received measurement signals or information can then be further processed in the associated evaluation and / or control unit. The data transmission is conducted by cable or wirelessly by radio. In this case as well, the power supply of the wireless optical sensor system can take place with the aid of batteries, rechargeable batteries or an energy harvesting module, wherein the detector (s) or sensor (s) are arranged by means of an energy harvesting module arranged in the lance is / are supplied with electrical energy.

To realize this fifth aspect of the invention, the inventive method is characterized in that by means of at least one in the lance head in the region of the at least one supersonic nozzle and optically through a mouth opening of the lance continuously aligned light sensor, in particular CCD or CMOS sensor, or at least one equipped camera during operation of the lance, in particular during a blowing process, preferably oxygen blowing process occurring in the lance head outside the lance optical emissions are detected.

Likewise, the measuring system for realizing this fifth aspect of the invention is characterized in that at least one light sensor, in particular a CCD or CMOS sensor, or at least one camera equipped therewith is arranged in the lance head in the region of the at least one supersonic nozzle optical aligned through a mouth opening of the blowing lance and the / is in line with the evaluation and / or process control unit and the detected during the operation of the lance, in particular during a blowing process, preferably Sauerstoffblasprozesses, occurring in the lance head outside the lance optical emissions and / or measures and / or during the operation of the blowing lance the at least one of the at least one light sensor (16) or the at least one camera connected to the evaluation and / or process control unit preferably online and to control the operation the lance provides.

In this case, it is particularly expedient if, in the case of a multi-hole lance having a plurality of supersonic nozzles, at least one detector or sensor is associated with each supersonic nozzle or is assigned to a corresponding lance of the measuring system.

In a further embodiment, the method and the measuring system provide that the lance is / are assigned to one or more detector (s) or sensor (s) from the group of pressure sensors, temperature sensors, vibration sensors and / or light sensors, or that the lance has one or more lances a plurality of detector (s) or sensor (s) from the group of pressure sensors, temperature sensors, vibration sensors and / or light sensors.

The measurement data transmission to the evaluation unit, for example a PC, and the power supply of the measurement sensors or detectors can be realized for example by a cable. When changing the lance but usually the lance head or the lower part of the lance is separated due to wear, exacerbations or damage. In this case there is a risk in cable-bound power supply that the cable is cut. A wireless measurement signal and measurement data transmission is therefore particularly advantageous. This can for example by a Radio transmission can be realized. In this case, to secure the power supply, the respective sensor or detector may be equipped with a battery or an energy harvesting module. The method according to the invention is therefore characterized in a further embodiment in that the measurement signal (s) obtained are conducted by the detector and / or sensor by means of a cable arranged in or on the lance or wirelessly by means of a detector and / or Sensor connected and arranged in the lance radio module of the evaluation and / or process control unit is / is supplied.

In this case, it is also possible in an advantageous manner for the detector (s) or sensor (s) to be supplied with electrical energy by means of an energy harvesting module arranged in the lance.

Finally, in an advantageous development of the invention, the measuring system is distinguished by the fact that the detector (s) or sensor (s) are conductively bound by means of a cable arranged in or on the lance or wirelessly by means of a radio module arranged in the lance with the evaluation unit. and / or process control unit is / are connected, wherein in particular the one or more wirelessly connected to the evaluation and / or process control unit (s) detector or sensor (s) is preferably connected to a arranged in the lance energy harvesting module /are.

The detectors and / or sensors listed above can thus be arranged equipped with a wireless information and / or energy transmission within the lance. As a result, the expense of reinstalling the sensors and / or detectors is less than with wired or wired sensors or detectors. An advantage of this lower cost of reinstallation, especially when the lance above the sensors, for example, due to existing at the lance lances, be broken and a new lance part to be welded got to. The wirelessly designed in this sense sensors can be equipped to avoid the change of the power source with an energy harvesting power source or an energy harvesting module. In the lance can serve as a source of energy, for example, a generator that draws its energy from the gas flow or the vibration of the lance. In the case of a vibration measurement, the energy can be obtained when using an energy harvesting module, for example, from the resulting from the vibrations of the lance energy.

When using a plurality of selectively aligned optical sensors or detectors or a camera equipped with it, the location of the ignition can be determined in addition to the ignition even with commonly used Mehrlochblaslanzen. Since a lance head usually contains a plurality of supersonic nozzles, each supersonic nozzle can be associated with a corresponding light sensor or detector. In this way, there is the possibility of a differentiated detection of the ignition of the oxygen jets.

With the aid of the evaluation and / or control unit, the measurement signals detected or measured or determined by the sensors and / or detectors can be evaluated and used for the control of the process and the operation of the underlying model.

Fig. 1

in schematischer Schnittdarstellung eine Blaslanze mit zugeordnetem metallurgischem Gefäß und Gasversorgung,

Fig. 2

in schematischer Darstellung den Bereich eines Lanzenkopfes mit darin angeordnetem leitungsgebundenem Sensor,

Fig. 3

in schematischer Darstellung den Bereich eines Lanzenkopfes mit darin angeordnetem Drahtlos-Sensor und in

Fig. 4

in schematischer Darstellung eine Sensorik zur Erkennung des Zündortes.

The invention is explained in more detail below by way of example with reference to a drawing. This shows in

Fig. 1

in a schematic sectional view of a lance with associated metallurgical vessel and gas supply,

Fig. 2

a schematic representation of the area of a lance head with a wire-bound sensor arranged therein,

Fig. 3

in a schematic representation of the area of a lance head with arranged therein wireless sensor and in

Fig. 4

in a schematic representation of a sensor for detecting the Zündortes.

The Fig. 1 shows a blown lance 2 introduced from above into a metallurgical vessel 1 designed as a converter, in particular an oxygen blowing lance, which, in its operation in the in Fig. 1 shown working position gas blows out on a metal melt 3 located in the metallurgical vessel 1. At the at the presentation in Fig. 1 lower end of the lance 2 is a blow lance tip forming, interchangeable lance head 4 is arranged. Within the lance head 4 more supersonic nozzles are formed, which is indicated by the outgoing from the lance head 4 dashes.

The blow lance 2 is connected to a gas feed station 6 via a feed line 5 comprising pipes or hoses, which comprises a valve station 7 by means of which the gas 8 to be discharged from the lance head 4 can be fed controllably to the feed line 5. The gas 8 in the exemplary embodiment is a gas used in the case of oxygen (blowing), ie oxygen or an oxygen-containing gas mixture, for example an argon-oxygen gas. However, it is also possible to feed nitrogen or a nitrogen-containing gas mixture to the feed line 5. When flowing into the supply line 5 gas 8 can be at the valve station 7 set a pressure p _vs as a form and adjust. For the process and process control during operation of the lance 2, the pressure p _{vs is} continuously measured.

In the metallurgical vessel 1 or converter prevails during operation of the lance 2, a static (counter) pressure p _A. The individual supersonic nozzles or Laval nozzles of the lance head 4 are designed for an ideal operating point (Design Point), in which the design pressure p ₀ and the design temperature T ₀ prevail at the entrance of each supersonic nozzle. During operation of the blowing lance 2, the respectively prevailing inlet _pressure p _o and the respective prevailing inlet _temperature T _{o are continuously} determined and / or measured at the lance head 4 at the entrance of each supersonic nozzle or Laval nozzle by detection. Since the pressure loss _Ap from the valve station to the entrance area of each supersonic _{nozzle is} determined by the relationship _Ap = p _vs -p _0t , it is possible to make an online calculation of the pressure loss _Ap and thus control the deviation of the inlet _pressure p _0t and to carry out the inlet _temperature T _0t of the individual supersonic _nozzle supplied oxygen of the design variables p ₀ and T ₀ during the blowing process. In this way, the upstream pressure p _vs at the valve station 7 can be adjusted so that the correct design _pressure p _{0 is present} as the inlet _pressure p _0t at the inlet of the respective supersonic nozzle or Laval nozzle.

The detection of the inlet _pressure p _0t and the inlet _temperature T _0t by means of at least one detector or sensor 9a, 9b, which is arranged in the lance head 4, that he the inlet _pressure p _0t and / or the inlet _temperature T _{0t of} the gas to be blown 8 at the entrance of all or detects and / or measures at least one supersonic nozzle (s) assigned to it. In the event that a detector or sensor 9a, 9b is in each case assigned to the input of a supersonic nozzle, a number of detectors and / or sensors 9a, 9b corresponding to the number of Laval nozzles or supersonic nozzles is respectively arranged in the lance head 4.

Schematically, the arrangement of the at least one sensor or detector 9a, 9b in the FIGS. 2 and 3 shown. The FIG. 2 shows a arranged by means of a holder 10 in the lance head 4 detector or sensor 9a, which is connected via a line, in particular a cable 11, with an evaluation and / or control unit, not shown.
In the embodiment of the FIG. 3 finds a detector or sensor 9b use, which is connected to an associated radio module 12, with to which the measurement signals detected and / or measured by the detector or sensor 9b are transmitted wirelessly, in particular by radio, to the evaluation and / or control unit (not shown). In this case, the radio module 12 comprises a power source in the form of a battery or an energy harvesting module.

The measuring signals obtained by means of the at least one detector or sensors 9a, 9b are transmitted continuously to the connected evaluation and / or process control unit online during operation of the blowing lance 4 in the blowing process, where they are provided for controlling the operation of the lance 2 and then also used to control the blowing process.

The at least one detector or sensor 9a, 9b is a pressure sensor for determining the inlet pressure p _0t . However, several or multi-function detectors or sensors 9a, 9b may well be present and arranged in the lance head 4, which are selected from the group of pressure sensors, temperature sensors, vibration sensors and / or light sensors.

Vibration sensors arranged in the lance head 4 detect and / or measure the oscillation amplitude A and / or the oscillation frequency ω of the lance 2.

Detectors or sensors 9a, 9b designed as light sensors detect optical emissions when oxygen streams are ignited during oxygen blowing. The light sensors may be CCD sensors, CMOS sensors, photodiodes, photodetectors and cameras equipped with these sensors or detectors. With these, the radiation or optical emission occurring in the lance head 4 when igniting an oxygen jet is detected, or the change in the radiation intensity or optical emissions in the lance head 4 occurring when an oxygen jet is ignited detected. In this case, the respective detector or sensor 9a, 9b designed in the form of a light sensor can also be equipped and aligned such that it, as shown in FIG Fig. 4 is shown schematically detects the location of the ignition or the ignition 13 or detects. When using at least one, but preferably a plurality of directed optical sensors 9a, 9b or the use of a camera as an optical sensor can be determined in addition to the ignition even with commonly used Mehrlochblaslanzen the Zündort 13. In this case, the effect is exploited that when striking an emerging from the lance head 4 oxygen jet 8b on the molten metal 3 located in the metallurgical vessel 1 upon ignition of the oxygen beam 8b at the ignition 13, a focal spot is formed, whereas when hitting an oxygen beam 8a present in the molten metal 3 scrap 14 no focal spot is created. The impact point of the oxygen beam 8b thus shows a different radiation intensity and thus optical emission than the point of impact of the oxygen beam 8a. This can be used to detect focal spots and thus the ignition 13.

Claims (20)

Method for operating a blowing lance (2), in particular an oxygen blowing lance, which blows out a gas (8), in a metallurgical vessel (1), the lance head (4), preferably exchangeable, of the lance (2) having at least one supersonic nozzle,
characterized,
in that the at least one detector or sensor (9a, 9b) arranged in the lance head (4) in the region of the supersonic nozzle during operation of the lance (2), in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head (4) of the inlet pressure ( p _0t ) and / or the inlet _temperature (T _0t ) of the gas (8) at the at least one supersonic _nozzle and / or the oscillation amplitude (A) and / or the oscillation frequency (ω) of the lance (2)
and / or the ignition timing of the ignition in the oxygen blowing process and / or the location of ignition in the oxygen blowing process is detected and / or measured
and during the operation of the blowing lance (2) the measuring signal (s) obtained thereby are preferably supplied online to an evaluation and / or process control unit connected to the at least one detector or sensor (9a, 9b) and for controlling the operation of the Blow lance (2) is / are provided. A method according to claim 1, characterized in that by means of at least one in the lance head (4) arranged in the region of the at least one supersonic nozzle pressure sensor (9a, 9b) during operation of the lance (2), in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the Lance head (4) the inlet _pressure (p _0t ) of the gas (8) at the entrance of the at least one supersonic _nozzle () is detected and / or measured. Method according to claim 1 or 2, characterized in that by means of at least one temperature sensor (9a, 9b) arranged in the lance head (4) in the region of the at least one supersonic nozzle during the operation of the lance (2), in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head (4) the inlet _temperature (T _0t ) of the gas (8) at the entrance of the at least one supersonic _{nozzle is} detected and / or measured. Method according to one of claims 1 to 3, characterized in that at the same time, in particular continuously, the supply pressure (p _vs ) of the gas (8) at a spaced apart from the at least one supersonic nozzle gas supply station (6) is detected and / or measured. Method according to one of the preceding claims, characterized in that by means of at least one in the lance head (4) in the region of the at least one supersonic nozzle arranged vibration sensor (9a, 9b) during operation of the lance (2), in particular during a blowing process, preferably Sauerstoffblasprozesses, in particular continuously, in the lance head the oscillation amplitude (A) and / or the oscillation frequency (ω) of the lance (2) is detected and / or measured. Method according to one of the preceding claims, characterized in that by means of at least one in the lance head (4) in the region of the at least one supersonic nozzle arranged light sensor (9a, 9b), in particular CCD or CMOS sensor, during operation of the lance (2), In particular, during a blowing process, preferably oxygen blowing process, in the lance head (4) in an ignition of the Oxygen rays (8a, 8b) occurring (s) optical (s) emission (s) is / is detected. Method according to one of the preceding claims, characterized in that by means of at least one light sensor (9a, 9b), in particular CCD or CMOS sensor, arranged in the lance head (4) in the region of the at least one supersonic nozzle and optically aligned through an orifice of the lance. or at least one camera equipped with it during the operation of the lance (2), in particular during a blowing process, preferably Sauerstoffblasprozesses, in the lance head (4) outside the lance (2) occurring optical emissions are detected. Method according to one of the preceding claims, characterized in that each supersonic nozzle having at least one detector or sensor (9a, 9b) is assigned to each multi-jet nozzle having a plurality of supersonic nozzles. Method according to one of the preceding claims, characterized in that the blowing lance (2) is / are assigned one or more detector (s) or sensor (s) (9a, 9b) from the group of pressure sensors, temperature sensors, vibration sensors and / or light sensors , Method according to one of the preceding claims, characterized in that the obtained (s) measurement signal (s) of the detector or sensor (9a, 9b) conducted by means of a cable arranged in or on the lance (11) or wirelessly by means of a the radio module (12) connected to the detector and / or sensor (9a, 9b) and supplied in the lance (2) is / are fed to the evaluation and / or process control unit. Method according to one of the preceding claims, characterized in that the detector (s) or sensor (s) (9a, 9b) is / are supplied with electrical energy by means of an energy harvesting module arranged in the lance (2). Measuring system for determining during operation of a gas lance (2) blowing out gas (8), in particular an oxygen lance, in a metallurgical vessel (1) for process control, the measuring system comprising a lance (2), preferably an oxygen lance, having at least one supersonic nozzle, preferably interchangeable, lance head (4) and comprises an evaluation and / or process control unit receiving and processing the measurement signals,
characterized,
that in the lance head (4) at least one detector or sensor (9a, 9b) is arranged in the region of the at least one supersonic nozzle, which is in line communication with the evaluation and / or process control unit and during operation of the lance (2), in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head (4) the inlet _pressure (p _0t ) and / or the inlet _temperature (T _0t ) of the gas (8) at the at least one supersonic _nozzle
and / or the oscillation amplitude (A) and / or the oscillation frequency (ω) of the lance (2)
and / or detects and / or measures the ignition timing of the ignition in the oxygen blowing process and / or the location of the ignition in the oxygen blowing process
and during the operation of the blowing lance (2), the measuring signal (s) obtained during the operation of the blowing lance (2) are preferably fed online to the evaluation and / or process control unit connected to the at least one detector or sensor (9a, 9b) and are used to control the operation of the Blow lance (2) provides. Measuring system according to claim 12, characterized in that in the lance head (4) at least one pressure sensor (9a, 9b) is arranged in the region of the at least one supersonic nozzle, which is in line communication with the evaluation and / or process control unit and during operation of the Blow lance (2), in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head (4) detects and / or measures the inlet _pressure (p _0t ) of the gas (8) at the entrance of the at least one supersonic _nozzle and the one or more obtained ( n) measuring signal (s) during operation of the lance (2) of the at least one pressure sensor (9a, 9b) connected evaluation and / or process control unit preferably online feeds and provides for controlling the operation of the lance (2). Measuring system according to claim 12 or 13, characterized in that in the lance head (4) in the region of the at least one supersonic nozzle at least one temperature sensor (9a, 9b) is arranged, which is in line communication with the evaluation and / or process control unit and during the Operation of the lance (2), in particular during a blowing process, preferably oxygen blowing process, in particular continuously, in the lance head (4) detects and / or measures the inlet _temperature (T _0t ) of the gas (8) at the entrance of the at least one supersonic _nozzle and the or the case during the operation of the blowing lance (2), the obtained measuring signal (s) preferably feeds online to the evaluation and / or process control unit connected to the at least one temperature sensor (9a, 9b) and provides for controlling the operation of the blowing lance (2). Measuring system according to one of claims 12 to 14, characterized in that in the lance head (4) in the region of the at least one supersonic nozzle at least one vibration sensor (9a, 9b) is arranged, the line with the evaluation and / or process control unit in Connection stands and during operation of the lance (2), in particular during a blowing process, preferably Sauerstoffblasprozesses, in particular continuously, in the lance head (4) the oscillation amplitude (A) and / or the oscillation frequency (ω) of the lance (2) detected and / or measures and / or during the operation of the blowing lance (2) of the at least one vibration sensor (9a, 9b) connected to the evaluation and / or process control unit preferably online feeds and the or the resulting measurement signal (s) and to control the operation of the Blow lance (2) provides. Measuring system according to one of claims 12 to 15, characterized in that at least one light sensor (9a, 9b), in particular a CCD or CMOS sensor, or at least one camera equipped therewith is arranged in the lance head (4) in the region of the at least one supersonic nozzle which is / are in line with the evaluation and / or process control unit and during operation of the lance (2), in particular during a blowing process, preferably Sauerstoffblasprozesses, in the lance head (4) in an ignition of the oxygen jets (8a, 8b ) detects and / or measures occurring optical emission (s) and / or the measurement signal (s) obtained thereby during the operation of the lance (2) which is applied to the at least one light sensor (9a, 9b). , in particular CCD or CMOS sensor or the at least one camera, connected evaluation and / or process control unit preferably feeds online and provide for controlling the operation of the lance (2) t. Measuring system according to one of claims 12 to 16, characterized
characterized in that in the lance head (4) in the region of the at least one supersonic nozzle at least one light sensor (9a, 9b), in particular a CCD or CMOS sensor, or at least one camera equipped therewith is arranged, the / optically through an orifice of the Blow lance (2) is aligned and the / is in line with the evaluation and / or process control unit and the / during operation of the lance (2), in particular during a blowing process, preferably Sauerstoffblasprozesses, in the lance head (4) outside the lance (2) detects and / or measures occurring optical emissions and the one or more measurement signal (s) obtained during the operation of the lance (2) to the at least one light sensor (9a, 9b) or the at least one camera connected evaluation and / or process control unit preferably online feeds and provides for controlling the operation of the lance (2). Measuring system according to one of claims 12-17, characterized in that the blowing lance (2) is designed as a plurality of supersonic nozzles having multi-hole lance, each of the supersonic nozzles is assigned at least one detector or sensor (9a, 9b). Measuring system according to one of claims 12-18, characterized in that the lance (2) one or more detector (s) or sensor (s) (9a, 9b) from the group of pressure sensors, temperature sensors, vibration sensors and / or light sensors. Measuring system according to one of Claims 12-18, characterized in that the detector (s) or sensor (s) (9a, 9b) are conductively bound by means of a cable (11) arranged in or on the lance (2) or wirelessly by means of a cable in the lance arranged radio module (12) is connected to the evaluation and / or process control unit is / are, in particular the one or more wirelessly connected to the evaluation and / or process control unit (s) detector or sensor (s) (9a 9b) is / are preferably connected to an energy harvesting module arranged in the lance (2).

Images