EP0516613B1 - Plant comprising a shaft, in particular a reduction shaft furnace - Google Patents
Plant comprising a shaft, in particular a reduction shaft furnace Download PDFInfo
- Publication number
- EP0516613B1 EP0516613B1 EP92890127A EP92890127A EP0516613B1 EP 0516613 B1 EP0516613 B1 EP 0516613B1 EP 92890127 A EP92890127 A EP 92890127A EP 92890127 A EP92890127 A EP 92890127A EP 0516613 B1 EP0516613 B1 EP 0516613B1
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- EP
- European Patent Office
- Prior art keywords
- shaft
- bulk material
- plant according
- charging
- temperature measuring
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/02—Making spongy iron or liquid steel, by direct processes in shaft furnaces
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
- C21B7/18—Bell-and-hopper arrangements
- C21B7/20—Bell-and-hopper arrangements with appliances for distributing the burden
Definitions
- the invention relates to a system according to the preamble of claim 1.
- the loading device is formed by a plurality of pipes rigidly arranged with respect to the shaft, through which the bulk material enters the shaft to form a plurality of bulk material cones, the respective tips of which are always at the same height at the mouth of the associated pipe.
- the continuous feeding of the bulk material offers the advantage of constant temperature in the upper end region of the shaft, which is not the case when the bulk material is introduced discontinuously, for example in a blast furnace with a charging device designed as a rotary chute, because it is batch-wise and generally cold bulk material, there is a sudden drop in gas temperature.
- a disadvantage of the known continuous loading devices is that the fine-grain portion of the bulk material of the bulk material is segregated on the bulk material cone, since the coarse-grain portion rolls further on the surface of the bulk material cone than the fine-particle bulk material. This leads to an uneven gasification of the bulk material and, in the case of direct reduction of iron ore, to an unequal degree of reduction, this inequality being exacerbated by the fact that the gases have a higher temperature at points of a higher gasification rate.
- V-fill (known from DE-31 41 280 A)
- M-fill (known from DE-38 34 969 A) or A-fill
- the coarser particles run to the edge, the finer ones remain more in the middle.
- the gas flow is again pushed to the edge, because firstly the specific resistance of a coarse-grained bed is lower and secondly the path to the bed surface is shorter.
- a system in which the bulk material is conveyed into the interior of the shaft with a constant feeding speed with the aid of a loading device designed as a conveyor belt, the loading device having a horizontally movable carriage so that the loading material can be moved to different locations Setting the shaft cross section can be introduced.
- the gas temperatures can be measured by means of a thermocouple, which is arranged on the carriage approximately at the point at which the feed material is thrown off, and depending on the same, the feed speed of the feed device can be regulated in such a way that the material is dispensed at locations of relatively high permeability increased and the material output is reduced via places of relatively low permeability.
- a disadvantage here is the relatively complicated loading device, especially for a shaft with high gas temperatures. It is also disadvantageous that the temperature measuring device is moved with the conveyor belt over the cross section of the shaft, so that only the temperature at one point, namely at the discharge point of the load, can be determined. As a result, it is not possible to determine and correct deviations in the temperature distribution over the entire shaft cross section.
- FR-1 406 976 A shows a system with a loading device, in which a loading pipe is rotatably mounted at the upper end of the furnace.
- This feed pipe is angled in the lower section, and it widens towards the lower mouth so that it can cover almost half the diameter of the furnace.
- this feed pipe contains a partition and a flap above it, in order to be able to distribute the feed material over one or the other subchannel, i.e. either feed more radially outside or more radially inside the furnace.
- three transmitter devices are also provided to record the temperature, pressure and gas composition on different radii (inside, center and outside). These donor devices are installed inside the feed pipe, where the bulk material flow is fed; In addition, a temperature, pressure and gas composition measurement is always carried out at the respective point on the rotating feed pipe.
- a generic system in the form of a shaft furnace is known from US-4 178 151 A.
- a plurality of outlet pipes for the formation of pouring cones is provided within the upper part of the shaft, these pipes being arranged in a stationary manner and at a regular distance from one another and at a distance from the furnace wall.
- the muzzle pipes are connected to feed pipes that start from a loading funnel.
- Each muzzle tube is assigned temperature measuring devices in the form of measuring points with thermocouples, which are attached to the furnace wall below the muzzle tubes and are intended to lie within the bulk material during operation. If the temperature rises sharply at a measuring point, the operator is signaled that there is insufficient bulk material in the muzzle pipes in question. Devices for the individual metering of the quantity of bulk material to the individual outlet pipes are not provided. Due to the rigid arrangement of the muzzle pipes, the bulk material cones are always formed in the same places.
- the invention aims at avoiding the disadvantages and difficulties described and has as its object to create a system of the type described at the outset, which has a uniform treatment of the bulk material, i.e. ensures uniform gas flow across the entire cross-section of the shaft with little design effort and high operational reliability.
- 1 designates an upper part of a refractory-lined, essentially cylindrical shaft 2 of a direct reduction shaft furnace, in which lumpy bulk material continuously charged from above, namely iron ore 3, is reduced by means of the reducing gas flowing through the shaft 2 from bottom to top.
- the reduction gas is introduced in this reduction process in the usual way through feed lines arranged at the lower third of the height of the shaft 2 on its casing 4.
- the loading of the shaft with the iron-containing bulk material 3 takes place via a loading device 5 which, according to the embodiment shown in FIG. 1, has a collecting container 6 which is arranged centrally to the shaft 2 and lies above the shaft 2. From the collecting container 6, which is fed continuously or discontinuously from above through a central opening 7, six feed pipes 9 are arranged, which are evenly distributed around the longitudinal axis 8 of the shaft and which open through the ceiling 10 of the shaft 2 into the interior 11 thereof.
- tubular mouth pieces 13 are articulated, the articulation being such that the mouth pieces 13 can be pivoted in the radial direction as seen from the longitudinal axis 8 of the shaft 2.
- the upper end 14 of each substantially straight and cylindrical mouthpiece 13 is funnel-shaped to protrude in each of the pivot positions of the mouthpieces 13 over the lower end 12 of the associated feed pipe 9, so that all bulk material 3 sinking through the feed pipes 9 by the subordinate ones Mouthpieces 13 flows and forms a bulk material cone 16 adjoining the lower opening 15, which is also of an enlarged design.
- a gas discharge opening 24 is provided on the side of the mouths of the feed pipes 9.
- thermocouples 25 are provided in a cross-sectional plane Q of the shaft 2, which are preferably designed as thermocouples. These thermocouples 25 are arranged in the interior of steel tubes 26 which extend radially across the cross section of the shaft 2 and in which the electrical connecting lines 27 are also guided. The steel tubes 26 protrude through the jacket 4 of the shaft 2 to the outside.
- the electrical connecting lines 27, which are led to the outside via the steel pipes 26, are connected to a computing and control unit (not shown), which in turn is coupled to the actuating cylinder 18 for adjusting the position of the mouth pieces 13 in the manner described below.
- the bulk material In the case of a stationary pouring of the bulk material 3 in the interior 11 of the shaft 2, the bulk material is segregated, since the bulk of the bulk material 3 on the bulk material cone 16 rolls further outwards. As a result, the finer bulk material 3 collects in the center of the bulk material cone, i.e. where the bulk material cone 16 has its greatest height and thus the longest gas passage path, so that, in addition to the longest gas passage path, a gas permeability which is lower than the edge zones of a bulk material cone 16 occurs. This causes an uneven gasification and thus an uneven degree of reduction of the ore.
- the gas emerging from the bulk material 3 has a higher temperature, so that on the basis of the temperature values measured in a cross-sectional plane Q, the duration of the treatment can be concluded from the gas flowing through the bulk material below the temperature measuring device 25.
- the measured temperature values deviate from a temperature value to a certain extent, the introduction of the bulk material 3 is changed such that the position of the bulk material cone 16 is displaced, namely in the radial direction according to the embodiment shown in FIGS.
- the charging device 5 has both a central charging pipe 9 'and charging pipes 9 lying radially at a certain distance therefrom.
- All loading tubes 9, 9 ' are each provided with a telescopic over the loading tube 9, 9' slidable and fixable in different sliding positions mouthpiece 13 ', which makes it possible to bring the outlet openings 15 of the loading device 5 to different heights.
- peaks 17 of the bulk material cone 16 lying at different heights result, but also different types of fill, such as an A fill, which is shown in the left half of FIG. 3, or a V fill, which is in the right Image half of Fig. 3 is shown.
- FIG. 4 also enables a V-bed and an A-bed to be varied, the illustration being analogous to that of FIG. 3.
- a slide 28 is provided in the vertical direction, which can be shifted in different positions and can be fixed in these positions and is designed as a cylinder.
- the radially outer mouth pieces 13 In the raised position, the radially outer mouth pieces 13 graduallyen, which are formed in one piece with the loading pipes 9, 9 ⁇ , closes and, in the lowered position, blocks the centrally arranged mouthpiece 13 ⁇ with the aid of a conical insert 29 arranged centrally in the interior thereof.
- the pivotability of the mouthpieces 13 is such that a pure A-bed can be achieved if the mouthpieces 13 inwards to Longitudinal axis 8 of the shaft 2 are pivoted.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
- Manufacture Of Iron (AREA)
- Control Of Turbines (AREA)
Description
Die Erfindung betrifft eine Anlage gemäß dem Oberbegriff von Anspruch 1.The invention relates to a system according to the preamble of claim 1.
Es ist aus der DE-31 41 280 A und aus der DE-38 34 969 A bekannt, das Schüttgut über eine im oberen Endteil des Schachtes angeordnete Beschickungseinrichtung dem Schacht zuzuführen. Die Beschickungseinrichtung ist von einer Mehrzahl von gegenüber dem Schacht starr angeordneten Rohren gebildet, über die das Schüttgut unter Bildung einer Mehrzahl von Schüttgutkegeln, deren jeweilige Spitze stets in gleicher Höhe bei der Mündung des zugehörigen Rohres liegt, in den Schacht gelangt. Die kontinuierliche Zuführung des Schüttgutes bietet den Vorteil der Temperaturkonstanz im oberen Endbereich des Schachtes, die bei einer diskontinuierlichen Einbringung des Schüttgutes, wie zum Beispiel bei einem Hochofen mit einer als Drehschurre ausgebildeten Beschickungseinrichtung, nicht gegeben ist, da durch das chargenweise und in der Regel kalt eingebrachte Schüttgut ein plötzlicher Abfall der Gastemperatur erfolgt.It is known from DE-31 41 280 A and DE-38 34 969 A to feed the bulk material to the shaft via a loading device arranged in the upper end part of the shaft. The loading device is formed by a plurality of pipes rigidly arranged with respect to the shaft, through which the bulk material enters the shaft to form a plurality of bulk material cones, the respective tips of which are always at the same height at the mouth of the associated pipe. The continuous feeding of the bulk material offers the advantage of constant temperature in the upper end region of the shaft, which is not the case when the bulk material is introduced discontinuously, for example in a blast furnace with a charging device designed as a rotary chute, because it is batch-wise and generally cold bulk material, there is a sudden drop in gas temperature.
Nachteilig ist jedoch bei den bekannten kontinuierlichen Beschickungseinrichtungen, daß es am Schüttgutkegel zu einer Entmischung des Feinkorn- vom Grobkornanteil des Schüttgutes kommt, da der Grobkornanteil an der Oberfläche des Schüttgutkegels weiter abrollt als das feinteilige Schüttgut. Hierdurch kommt es zu einer ungleichen Durchgasung des Schüttgutes und im Falle einer Direktreduktion von Eisenerz zu einem ungleichen Reduktionsgrad, wobei diese Ungleichheit noch dadurch verstärkt wird, daß an Stellen einer höheren Durchgasungsgeschwindigkeit die Gase eine höhere Temperatur aufweisen.However, a disadvantage of the known continuous loading devices is that the fine-grain portion of the bulk material of the bulk material is segregated on the bulk material cone, since the coarse-grain portion rolls further on the surface of the bulk material cone than the fine-particle bulk material. This leads to an uneven gasification of the bulk material and, in the case of direct reduction of iron ore, to an unequal degree of reduction, this inequality being exacerbated by the fact that the gases have a higher temperature at points of a higher gasification rate.
Bei einer sogenannten V-Schüttung (bekannt aus der DE-31 41 280 A) gelangen - bedingt durch die Entmischung - die gröberen Partikel des Einsatzgutes in die Mitte, die feineren bleiben am Rand. Hierdurch wird der Gasstrom sehr stark zur Mitte gedrängt. Bei einer sogenannten M-Schüttung (bekannt aus der DE-38 34 969 A) bzw. A-Schüttung laufen die gröberen Partikel zum Rand, die feineren bleiben mehr in der Mitte. Dabei wird wiederum der Gasstrom mehr zum Rand gedrängt, da erstens der spezifische Widerstand einer Grobkornschüttung geringer ist und zweitens der Weg zur Schüttungsoberfläche kürzer ist.In a so-called V-fill (known from DE-31 41 280 A), due to the separation, the coarser particles of the feed material get into the middle, the finer particles remain at the edge. This pushes the gas flow very strongly towards the center. With a so-called M-fill (known from DE-38 34 969 A) or A-fill, the coarser particles run to the edge, the finer ones remain more in the middle. The gas flow is again pushed to the edge, because firstly the specific resistance of a coarse-grained bed is lower and secondly the path to the bed surface is shorter.
Bei der Reduktion von Stückerz ist eine gleichmäßige Durchgasung und Erwärmung im Schachtoberteil besonders wichtig, weil der Temperaturbereich des Niedrigtemperaturkornzerfalles (bis 7500) möglichst rasch durchschritten werden soll. Schlecht durchgaste Zonen werden langsamer erwärmt, woraus sich ein stärkerer Kornzerfall ergibt, was wiederum wegen des geringeren Lückenvolumens zu einem größeren Druckverlust und damit zu einer noch schlechteren Durchgasung führt. Insbesondere bei staubhaltigen Gasen kann die Erzschüttung als Festbettfilter dienen und damit die Durchgasung der Randpartien behindern.In the reduction of lump ore, even gas flow and heating in the top part of the shaft is particularly important because the temperature range of the low-temperature grain decay (up to 7500) should be passed through as quickly as possible. Zones with poor gas permeability are warmed up more slowly, which results in greater grain disintegration, which in turn leads to a greater pressure loss due to the smaller gap volume and thus to an even worse gas flow. In the case of gases containing dust in particular, the ore bed can serve as a fixed bed filter and thus hinder the gassing of the peripheral parts.
Aus der DE-1 151 822 B ist eine Anlage bekannt, bei der das Schüttgut mit Hilfe einer als Förderband ausgebildeten Beschickungsvorrichtung mit gleichbleibender Zuführungsgeschwindigkeit in das Innere des Schachtes gefördert wird, wobei die Beschickungsvorrichtung einen horizontal beweglichen Wagen aufweist, so daß das Beschickungsgut an verschiedenen Stellen des Schachtquerschnittes einbringbar ist. Mittels eines Thermoelementes, welches an dem Wagen etwa an der Stelle angeordnet ist, an der das Beschickungsgut abgeworfen wird, lassen sich die Gastemperaturen messen, und in Abhängigkeit derselben kann die Vorschubgeschwindigkeit der Beschickungsvorrichtung derart geregelt werden, daß über Stellen von verhältnismäßig hoher Durchlässigkeit die Materialabgabe gesteigert und über Stellen von verhältnismäßig niedriger Durchlässigkeit die Materialabgabe vermindert wird.From DE-1 151 822 B a system is known in which the bulk material is conveyed into the interior of the shaft with a constant feeding speed with the aid of a loading device designed as a conveyor belt, the loading device having a horizontally movable carriage so that the loading material can be moved to different locations Setting the shaft cross section can be introduced. The gas temperatures can be measured by means of a thermocouple, which is arranged on the carriage approximately at the point at which the feed material is thrown off, and depending on the same, the feed speed of the feed device can be regulated in such a way that the material is dispensed at locations of relatively high permeability increased and the material output is reduced via places of relatively low permeability.
Nachteilig ist hierbei die relativ komplizierte Beschickungsvorrichtung, insbesondere für einen Schacht mit hohen Gastemperaturen. Weiters ist nachteilig, daß die Temperaturmeßeinrichtung mit dem Förderband über den Querschnitt des Schachtes verfahren wird, so daß immer nur die Temperatur an einer Stelle, nämlich an der Abwurfstelle des Beschickungsgutes, festgestellt werden kann. Hierdurch ist es nicht möglich, Abweichungen in der Temperaturverteilung über den gesamten Schachtquerschnitt festzustellen und zu korrigieren.A disadvantage here is the relatively complicated loading device, especially for a shaft with high gas temperatures. It is also disadvantageous that the temperature measuring device is moved with the conveyor belt over the cross section of the shaft, so that only the temperature at one point, namely at the discharge point of the load, can be determined. As a result, it is not possible to determine and correct deviations in the temperature distribution over the entire shaft cross section.
Aus der EP-0 261 432 A ist es bei einem Durchgasungsschacht bekannt, mit Hilfe einer Temperaturmessung die Schüttguteinbringung in den Schacht zu steuern. Dies erfolgt jedoch nicht kontinuierlich, sondern durch diskontinuierliches Chargieren, was gemäß der EP-0 261 432 A unbedingt erforderlich ist, da im achsnahen Teil des Schachtinnenraumes Schüttgut mit einer anderen Zusammensetzung chargiert werden soll als im radial anschließenden äußeren Bereich des Schachtinnenraumes. Hier besteht zudem die Gefahr der Beschädigung der Temperaturmeßeinrichtung durch beim Chargiervorgang herabfallendes Chargiergut, da die Temperaturmeßeinrichtung unterhalb der Chargiereinrichtung angeordnet ist.From EP-0 261 432 A it is known in a gas passage shaft to control the introduction of bulk material into the shaft by means of a temperature measurement. However, this does not take place continuously, but rather by batchwise charging, which is absolutely necessary according to EP-0 261 432 A, since bulk material in the part of the shaft interior near the axis is to be charged with a different composition than in the radially adjoining part outer area of the shaft interior. Here there is also the risk of damage to the temperature measuring device due to the charging material falling during the charging process, since the temperature measuring device is arranged below the charging device.
Die FR-1 406 976 A zeigt eine Anlage mit einer Beschickungseinrichtung, bei der ein Beschickungsrohr am oberen Ende des Ofens drehbar gelagert ist. Dieses Beschickungsrohr ist im unteren Abschnitt abgewinkelt, und es erweitert sich zur unteren Mündung hin, um so annähernd den halben Durchmesser des Ofens bestreichen zu können. Im Inneren enthält dieses Beschickungsrohr eine Trennwand sowie oberhalb davon eine Klappe, um das Beschickungsgut auf den einen oder anderen Teilkanal verteilen zu können, d.h. entweder mehr radial außen oder mehr radial innen dem Ofen zuzuführen. Am unteren Ende des rotierenden Beschickungsrohres sind ferner drei Gebereinrichtungen vorgesehen, um die Temperatur, den Druck sowie die Gaszusammensetzung auf verschiedenen Radien (innen, mittig und außen) zu erfassen. Diese Gebereinrichtungen sind innerhalb des Beschickungsrohres angebracht, wo der Schüttgutstrom zugeführt wird; überdies erfolgt eine Temperatur-, Druck- und Gaszusammensetzungsmessung immer an der jeweiligen Stelle des rotierenden Beschickungsrohres.FR-1 406 976 A shows a system with a loading device, in which a loading pipe is rotatably mounted at the upper end of the furnace. This feed pipe is angled in the lower section, and it widens towards the lower mouth so that it can cover almost half the diameter of the furnace. Inside, this feed pipe contains a partition and a flap above it, in order to be able to distribute the feed material over one or the other subchannel, i.e. either feed more radially outside or more radially inside the furnace. At the lower end of the rotating feed pipe, three transmitter devices are also provided to record the temperature, pressure and gas composition on different radii (inside, center and outside). These donor devices are installed inside the feed pipe, where the bulk material flow is fed; In addition, a temperature, pressure and gas composition measurement is always carried out at the respective point on the rotating feed pipe.
Eine gattungsgemäße Anlage in Form eines Schachtofens ist aus der US-4 178 151 A bekannt. Dabei ist innerhalb des Oberteils des Schachtes eine Mehrzahl von Mündungsrohren zur Bildung von Schüttkegeln vorgesehen, wobei diese Rohre ortsfest und in regelmäßigem Abstand zueinander und im Abstand zur Ofenwand angeordnet sind. Die Mündungsrohre sind mit Beschickungsrohren verbunden, die von einem Beschickungstrichter ausgehen. Jedem Mündungsrohr sind Temperaturmeßeinrichtungen in Form von Meßstellen mit Thermoelementen zugeordnet, die unterhalb der Mündungsrohre an der Ofenwand angebracht sind und im Betrieb innerhalb des Schüttgutmaterials liegen sollen. Bei einem krassen Temperaturanstieg an einer Meßstelle wird dem Bedienungspersonal signalisiert, daß bei den betreffenden Mündungsrohren zuwenig Schüttgutmaterial vorhanden ist. Einrichtungen zur individuellen Dosierung der Schüttgutmenge zu den einzelnen Mündungsrohren sind nicht vorgesehen. Durch die starre Anordnung der Mündungsrohre werden die Schüttgutkegel stets an den gleichen Stellen gebildet.A generic system in the form of a shaft furnace is known from US-4 178 151 A. A plurality of outlet pipes for the formation of pouring cones is provided within the upper part of the shaft, these pipes being arranged in a stationary manner and at a regular distance from one another and at a distance from the furnace wall. The muzzle pipes are connected to feed pipes that start from a loading funnel. Each muzzle tube is assigned temperature measuring devices in the form of measuring points with thermocouples, which are attached to the furnace wall below the muzzle tubes and are intended to lie within the bulk material during operation. If the temperature rises sharply at a measuring point, the operator is signaled that there is insufficient bulk material in the muzzle pipes in question. Devices for the individual metering of the quantity of bulk material to the individual outlet pipes are not provided. Due to the rigid arrangement of the muzzle pipes, the bulk material cones are always formed in the same places.
Die Erfindung bezweckt die Vermeidung der beschriebenen Nachteile und Schwierigkeiten und stellt sich die Aufgabe, eine Anlage der eingangs beschriebenen Art zu schaffen, welche eine gleichmäßige Behandlung des Schüttgutes, d.h. eine gleichmäßige Durchgasung desselben, über den gesamten Querschnitt des Schachtes bei geringem konstruktivem Aufwand sicherstellt und eine hohe Betriebssicherheit aufweist.The invention aims at avoiding the disadvantages and difficulties described and has as its object to create a system of the type described at the outset, which has a uniform treatment of the bulk material, i.e. ensures uniform gas flow across the entire cross-section of the shaft with little design effort and high operational reliability.
Ausgehend von einer Anlage gemäß dem Oberbegriff des Anspruches 1 wird diese Aufgabe erfindungsgemäß durch die Merkmale des kennzeichnenden Teiles dieses Anspruches gelöst.Starting from a system according to the preamble of claim 1, this object is achieved according to the invention by the features of the characterizing part of this claim.
Vorteilhafte Ausführungsformen und Weiterbildungen sind in den Unteransprüchen angegeben.Advantageous embodiments and further developments are specified in the subclaims.
Die Erfindung wird nachfolgend anhand der Zeichnung an mehreren Ausführungsformen näher erläutert; es zeigen:
- Fig.1 den Oberteil eines Schachtes eines Direktreduktionsschachtofens zur Direktreduktion von Eisenerz im Längsschnitt;
- Fig.2 einen gemäß der Linie II-II der Fig.1 geführten Schnitt gemäß einer ersten Ausführungsform; und
- die Fig.3, 4 und 5 jeweils weitere Ausführungsformen in zu Fig.l analoger Darstellung.
- 1 shows the upper part of a shaft of a direct reduction shaft furnace for the direct reduction of iron ore in longitudinal section;
- 2 shows a section according to line II-II of FIG. 1 according to a first embodiment; and
- 3, 4 and 5 each further embodiments in a representation analogous to Fig.l.
Mit 1 ist ein Oberteil eines feuerfest ausgekleideten im wesentlichen zylindrischen Schachtes 2 eines Direktreduktionsschachtofens bezeichnet, in dem von oben kontinuierlich chargiertes stückiges Schüttgut, nämlich Eisenerz 3, mittels den Schacht 2 von unten nach oben durchströmenden Reduktionsgas reduziert wird. Die Einleitung des Reduktionsgases erfolgt in bei diesem Reduktionsverfahren üblicher Weise durch am unteren Drittel der Höhe des Schachtes 2 an dessen Mantel 4 angeordnete Speiseleitungen.1 designates an upper part of a refractory-lined, essentially
Die Beschickung des Schachtes mit dem eisenhältigen Schüttgut 3 erfolgt über eine Beschickungseinrichtung 5, die gemäß der in Fig.1 dargestellten Ausführungsform einen zentral zum Schacht 2 angeordneten und oberhalb des Schachtes 2 liegenden Sammelbehälter 6 aufweist. Von dem Sammelbehälter 6, der von oben über eine zentrale Öffnung 7 kontinuierlich oder diskontinuierlich beschickt wird, gehen sechs um die Längsachse 8 des Schachtes gleichmäßig verteilt angeordnete Beschickungsrohre 9 aus, die durch die Decke 10 des Schachtes 2 in dessen Inneres 11 münden.The loading of the shaft with the iron-containing
An den knapp unterhalb der Decke 10 liegenden Enden 12 der Beschickungsrohre 9 sind rohrförmige Mündungsstücke 13 angelenkt, wobei die Anlenkung so getroffen ist, daß die Mündungsstücke 13 von der Längsachse 8 des Schachtes 2 aus gesehen in radialer Richtung verschwenkt werden können. Das obere Ende 14 jedes im wesentlichen gerade und zylindrisch ausgebildeten Mündungsstückes 13 ist trichterförmig erweitert, um in jeder der Schwenkstellungen der Mündungsstücke 13 über das untere Ende 12 des zugehörigen Beschickungsrohres 9 zu ragen, so daß sämtliches durch die Beschickungsrohre 9 absinkendes Schüttgut 3 durch die nachgeordneten Mündungsstücke 13 fließt und einen an der unteren ebenfalls erweitert ausgebildeten Öffnung 15 anschließenden Schüttgutkegel 16 bildet.At the
Wie aus Fig. 1 ersichtlich, liegen die Spitzen 17, d.h. die oberen Enden der Schüttgutkegel 16 in Abhängigkeit der Schwenklage der Mündungsstücke 13 näher an oder weiter entfernt von der Längsachse 8 des Schachtes 2 sowie in geringem Maß höher oder tiefer.As can be seen from Fig. 1, the
Zum Verschwenken der Mündungsstücke von der in Fig. 1 mit vollen Linien dargestellten Lage in die in Fig. 1 mit strichpunktierten Linien gezeigte Lage dient ein oberhalb der Decke 10 des Schachtes 2 und geschützt in einem Gehäuse angeordneter Stellzylinder 18, dessen Kolben 19 über ein über Umlenkrollen 20 in das Innere 11 des Schachtes 2 geführtes Seil 21 an einem mit dem Stellzylinder 18 heb- und senkbaren Stellkeil 22 befestigt ist. An dem Stellkeil 22 liegen an den Mündungsstücken 13 befestigte und radial nach innen abstehende Gleitkufen 23 an, die sich nach oben in radialer Richtung zur Längsachse 8 hin erweitern.To pivot the mouthpieces from the position shown in full lines in Fig. 1 in the position shown in Fig. 1 with dash-dotted lines is used above the
An der Decke 10 des Schachtes 2 ist seitlich der Einmündungen der Beschickungsrohre 9 eine Gasabzugsöffnung 24 vorgesehen.On the
Knapp oberhalb der von den unteren Öffnungen 15 der Mündungsstücke 13 einnehmbaren obersten Lage sind in einer Querschnittsebene Q des Schachtes 2 verteilt mehrere Temperaturmesseinrichtungen 25 vorgesehen, die vorzugsweise als Thermoelemente ausgebildet sind. Diese Thermoelemente 25 sind im Inneren von sich radial über den Querschnitt des Schachtes 2 erstreckenden Stahlrohren 26, in denen auch die elektrischen Anschlußleitungen 27 geführt sind, angeordnet. Die Stahlrohre 26 ragen durch den Mantel 4 des Schachtes 2 nach außen. Die elektrischen Anschlußleitungen 27, die über die Stahlrohre 26 nach außen geführt sind, sind an eine nicht dargestellte Rechen- und Steuereinheit angeschlossen, die wiederum mit dem Stellzylinder 18 zur Verstellung der Position der Mündungsstücke 13 in der nachfolgend beschriebenen Weise gekoppelt ist.Just above the uppermost layer that can be taken up by the
Bei einer stationären Schüttung des Schüttgutes 3 im Inneren 11 des Schachtes 2 kommt es zu einer Entmischung des Schüttgutes, da der Grobanteil des Schüttgutes 3 am Schüttgutkegel 16 weiter nach außen rollt. Hierdurch sammelt sich im Zentrum des Schüttgutkegels, also dort wo der Schüttgutkegel 16 seine größte Höhe und damit den längsten Gasdurchtrittsweg aufweist, das feinere Schüttgut 3, so daß zusätzlich zum längsten Gasdurchtrittsweg noch eine gegenüber den Randzonen eines Schüttgutkegels 16 erniedrigte Gasdurchlässigkeit auftritt. Dies bedingt eine ungleiche Durchgasung und damit einen ungleichmäßigen Reduktionsgrad des Erzes.In the case of a stationary pouring of the
Oberhalb der Stellen, an denen das Gas schneller durch das Schüttgut 3 dringt, weist das aus dem Schüttgut 3 austretende Gas eine höhere Temperatur auf, so daß aufgrund der in einer Querschnittsebene Q gemessenen Temperaturwerte auf die Behandlungsdauer durch das das Schüttgut unterhalb der Temperaturmeßeinrichtung 25 durchströmende Gas geschlossen werden kann. Erfindungsgemäß erfolgt bei über ein bestimmtes Maß von einem Temperaturwert abweichenden gemessenen Temperaturwerten eine anderung des Einbringens des Schüttgutes 3 dahingehend, daß die Lage der Schüttgutkegel 16 versetzt wird, und zwar gemäß der in den Fig 1 und 2 dargestellten Ausführungsform in radialer Richtung so weit, bis die in der Querschnittsebene Q gemessenen Temperaturwerte gleich groß sind oder nur um ein solches Maß voneinander abweichen, daß über den Querschnitt des Schachtes 2 gesehen auf eine Konstanz der das Schüttgut 3 durchströmenden Gasmenge und damit auf eine gleichmäßige Behandlung des Schüttgutes 3 durch das Gas geschlossen werden kann.Above the points at which the gas penetrates the
Gemäß der in Fig. 3 dargestellten Ausführungsform, bei der in jeder der beiden Bildhälften je ein Betriebszustand dargestellt ist, weist die Beschickungseinrichtung 5 sowohl ein zentrales Beschickungsrohr 9′ als auch von diesem radial in einer bestimmten Entfernung liegende Beschickungsrohre 9 auf. Alle Beschickungsrohre 9, 9′ sind jeweils mit einem teleskopisch über das Beschickungsrohr 9, 9′ schiebbaren und in verschiedenen Schiebepositionen fixierbaren Mündungsstück 13′ versehen, wodurch es möglich ist, die Austrittsöffnungen 15 der Beschickungseinrichtung 5 in unterschiedliche Höhen zu bringen. Als Folge davon ergeben sich nicht nur in unterschiedlichen Höhen liegende Spitzen 17 der Schüttgutkegel 16 sondern auch unterschiedliche Schüttungsarten, wie z.B. eine A-Schüttung, die in der Linken Bildhälfte der Fig. 3 dargestellt ist, oder eine V-Schüttung, die in der rechten Bildhälfte der Fig. 3 gezeigt ist.According to the embodiment shown in FIG. 3, in which an operating state is shown in each of the two halves of the picture, the
Die in Fig. 4 dargestellte Ausführungsform ermöglicht ebenfalls das Variieren zwischen einer V-Schüttung und einer A-Schüttung, wobei die Darstellung analog zu der der Fig. 3 ist. Hier ist im Inneren der Beschickungseinrichtung 5 ein in vertikaler Richtung in unterschiedliche Positionen verschiebbarer und in diesen Positionen fixierbarer und als Zylinder ausgebildeter Schieber 28 vorgesehen, der in gehobener Position die radial äußeren Mündungsstücke 13˝, die einstückig mit den Beschickungsrohren 9, 9˝ ausgebildet sind, verschließt und in abgesenkter Position das zentral angeordnete Mündungsstück 13˝ unter Zuhilfenahme eines zentrisch im Inneren desselben angeordneten kegelförmigen Einsatzes 29 absperrt.The embodiment shown in FIG. 4 also enables a V-bed and an A-bed to be varied, the illustration being analogous to that of FIG. 3. In the interior of the
Gemäß der in Fig. 5 dargestellten Ausführungsform, die ähnlich der in den Fig. 1 und 2 gezeigten Ausführungsform ist, ist die Verschwenkbarkeit der Mündungsstücke 13 soweit gegeben, daß eine reine A-Schüttung erreicht werden kann, wenn die Mündungsstücke 13 nach innen bis zur Längsachse 8 des Schachtes 2 geschwenkt sind.According to the embodiment shown in Fig. 5, which is similar to the embodiment shown in Figs. 1 and 2, the pivotability of the
Claims (10)
- Plant, in particular a reduction shaft furnace for the direct reduction of metallic ores (3), comprising a shaft (2) which, in its upper end region, includes gas exhaust means (at 24), charging means (5) for continuously charging bulk material (3) and having a plurality of stationary charging tubes (9; 9') to which mouth pieces (13; 13'; 13") are associated within the upper end region of the shaft (2) for the formation of conical piles (16) located in the shaft (2), as well as several temperature measuring means (25) fixedly mounted externally of the charging tubes (9, 9') in a cross-sectional plane (Q) on various diameter lines in the upper end region of the shaft (2), characterised in that the temperature measuring means (25) are provided above the bulk material (3) for measuring the temperature of the gas emerging from the bulk material (3) on a plurality of sites distributed over the free cross section of the shaft (2) at various distances from the shaft center, and that for a temperature-dependent control of the introduction of the bulk material, the mouth pieces (13; 13'; 13") are either- displaceable in the radial direction relative to the shaft cross section by actuation means (18, 22) (Figs. 1, 5), or- displaceable in terms of height by actuation means (Fig. 3), or- selectively lockable by actuation means (Fig. 4).
- Plant according to claim 1, characterised in that the tubular mouth piece (13') is designed as a telescopic tube. (Fig. 3).
- Plant according to claim 1 or 2, characterised in that the tubular mouth pieces (13) are designed as pivotable extensions of the stationary charging tubes (9).
- Plant according to any one of claims 1 to 3, characterised in that the mouth pieces (13, 13', 13") are arranged radially symmetrically with respect to the shaft cross section.
- Plant according to claim 4, characterised in that a tubular mouth piece (13', 13") is arranged centrically with respect to the shaft cross section (Figs. 3, 4).
- Plant according to claim 5, characterised in that tubular mouth pieces (9) radially directed with respect to the shaft cross section depart from the centric charging tube (9') and a slide (28) is provided in the interior of the centric charging tube, which selectively closes one or several of the radially outer mouth pieces (13") arranged at the charging tubes (9), or the centric mouth piece (13"), and which is displaceable by actuation means (Fig. 4).
- Plant according to any one of claims 1 to 6, charcterised in that the temperature measuring means (25) are arranged on carriers (26) spanning the shaft interior (11) in its region comprising the charging arrangement (5).
- Plant according to claim 7, characterised in that the carriers are comprised by steel tubes (26) and that the temperature measuring means (25) as well as the measuring lines (27) leading to the temperature measuring means (25) are arranged within the steel tubes (26).
- Plant according to any one of claims 1 to 8, characterised in that the temperature measuring means (25) are arranged between the mouth pieces (13, 13', 13").
- Plant according to any one of claims 1 to 9, characterised in that the temperature measuring means (25) are coupled with a computer and control unit, which in turn is coupled with the actuation means (18 to 23) for displacing at least one of the mouth pieces (13, 13') (Figs. 1, 3, 5) or for displacing the slide (28) between the central mouth piece (13") and the radially outer mouth pieces (13") (Fig. 4).
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT1094/91 | 1991-05-29 | ||
AT0109491A AT396482B (en) | 1991-05-29 | 1991-05-29 | PLANT WITH A SHAFT, ESPECIALLY REDUCTION TUBE |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0516613A1 EP0516613A1 (en) | 1992-12-02 |
EP0516613B1 true EP0516613B1 (en) | 1996-07-03 |
Family
ID=3506460
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP92890127A Expired - Lifetime EP0516613B1 (en) | 1991-05-29 | 1992-05-26 | Plant comprising a shaft, in particular a reduction shaft furnace |
Country Status (10)
Country | Link |
---|---|
US (1) | US5271609A (en) |
EP (1) | EP0516613B1 (en) |
JP (1) | JPH0672248B2 (en) |
KR (1) | KR960002482B1 (en) |
AT (1) | AT396482B (en) |
AU (1) | AU649829B2 (en) |
CA (1) | CA2069859C (en) |
DE (1) | DE59206689D1 (en) |
TW (1) | TW206985B (en) |
ZA (1) | ZA923952B (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT1315147B1 (en) * | 2000-11-14 | 2003-02-03 | Danieli Off Mecc | OVEN FOR THE DIRECT REDUCTION OF IRON OXIDES |
AT502479B1 (en) | 2005-10-24 | 2007-04-15 | Voest Alpine Ind Anlagen | METHOD AND DEVICE FOR CHARGING INSERTS |
KR100880773B1 (en) | 2008-01-23 | 2009-02-02 | (주) 씨엠테크 | A heating unit for fluid |
KR20220154452A (en) | 2021-05-13 | 2022-11-22 | 현대자동차주식회사 | Hopper for material powder and Material powder transfer method using the same |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1151822B (en) * | 1959-06-23 | 1963-07-25 | United States Steel Corp | Method and device for monitoring the loading of a shaft furnace |
DE1205997B (en) * | 1963-01-05 | 1965-12-02 | Demag Ag | Monitoring device for blast furnaces |
DE1230052B (en) * | 1963-09-16 | 1966-12-08 | Kloeckner Werke Ag | Method and device for the continuous control of the gas flow in the blast furnace shaft charging |
FR1406976A (en) * | 1964-09-08 | 1965-07-23 | Demag Ag | Method and additional loading devices for blast furnace |
DE1907224A1 (en) * | 1969-02-13 | 1970-09-03 | Demag Ag | Charge distributor for shaft furnaces |
GB1491519A (en) * | 1973-12-26 | 1977-11-09 | Midrex Corp | Apparatus for feeding dissimilarly sized particles into a shaft furnace |
JPS6032793B2 (en) * | 1978-02-03 | 1985-07-30 | 石川島播磨重工業株式会社 | Furnace top charging device |
JPS5934764B2 (en) * | 1978-02-07 | 1984-08-24 | 石川島播磨重工業株式会社 | shaft furnace |
US4178151A (en) * | 1978-03-02 | 1979-12-11 | Midrex Corporation | Apparatus for monitoring the feeding of particulate materials to a packed bed furnace |
JPS54128905A (en) * | 1978-03-31 | 1979-10-05 | Nippon Kokan Kk <Nkk> | Charging apparatus for raw material to blast furnace top |
SE441865B (en) * | 1981-03-10 | 1985-11-11 | Skf Steel Eng Ab | DEVICE TO ENCOURAGE SUPPLYING PIECE MATERIAL TO A SHAK |
KR950007781B1 (en) * | 1986-08-26 | 1995-07-18 | 가와사끼 세이데쓰 가부시끼가이샤 | Shaft furnace having means for charging and adjusting a premixture of ore and coke |
LU87341A1 (en) * | 1988-09-22 | 1990-04-06 | Wurth Paul Sa | LOADING SYSTEM FOR A TANK OVEN |
DE3834969A1 (en) * | 1988-10-13 | 1990-04-19 | Kortec Ag | FEEDING DEVICE FOR SHAFT OVENS, IN PARTICULAR STOVE OVENS |
-
1991
- 1991-05-29 AT AT0109491A patent/AT396482B/en active
-
1992
- 1992-05-26 TW TW081104127A patent/TW206985B/zh active
- 1992-05-26 DE DE59206689T patent/DE59206689D1/en not_active Expired - Fee Related
- 1992-05-26 EP EP92890127A patent/EP0516613B1/en not_active Expired - Lifetime
- 1992-05-27 AU AU17196/92A patent/AU649829B2/en not_active Ceased
- 1992-05-27 US US07/889,600 patent/US5271609A/en not_active Expired - Lifetime
- 1992-05-28 CA CA002069859A patent/CA2069859C/en not_active Expired - Fee Related
- 1992-05-29 JP JP4138996A patent/JPH0672248B2/en not_active Expired - Lifetime
- 1992-05-29 KR KR92009252A patent/KR960002482B1/en not_active IP Right Cessation
- 1992-05-29 ZA ZA923952A patent/ZA923952B/en unknown
Also Published As
Publication number | Publication date |
---|---|
TW206985B (en) | 1993-06-01 |
EP0516613A1 (en) | 1992-12-02 |
KR920021719A (en) | 1992-12-18 |
AU1719692A (en) | 1992-12-17 |
ZA923952B (en) | 1993-02-24 |
DE59206689D1 (en) | 1996-08-08 |
JPH05148522A (en) | 1993-06-15 |
JPH0672248B2 (en) | 1994-09-14 |
KR960002482B1 (en) | 1996-02-17 |
AU649829B2 (en) | 1994-06-02 |
CA2069859C (en) | 1997-02-25 |
ATA109491A (en) | 1993-01-15 |
US5271609A (en) | 1993-12-21 |
AT396482B (en) | 1993-09-27 |
CA2069859A1 (en) | 1992-11-30 |
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