EP0521523B1 - Process for running a cupola - Google Patents

Process for running a cupola Download PDF

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Publication number
EP0521523B1
EP0521523B1 EP92111337A EP92111337A EP0521523B1 EP 0521523 B1 EP0521523 B1 EP 0521523B1 EP 92111337 A EP92111337 A EP 92111337A EP 92111337 A EP92111337 A EP 92111337A EP 0521523 B1 EP0521523 B1 EP 0521523B1
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EP
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Prior art keywords
carbon dioxide
furnace
zone
cupola furnace
cupola
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EP92111337A
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German (de)
French (fr)
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EP0521523A1 (en
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Manfred Dr. Dipl.-Ing. Rossmann
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Linde GmbH
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Linde GmbH
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B1/00—Shaft or like vertical or substantially vertical furnaces
    • F27B1/10—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B1/16—Arrangements of tuyeres
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B11/00—Making pig-iron other than in blast furnaces
    • C21B11/02—Making pig-iron other than in blast furnaces in low shaft furnaces or shaft furnaces

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  • the invention relates to a method for operating a cupola furnace for the production of cast iron, in which the furnace shaft of the cupola furnace is filled with a corresponding insert or is constantly refilled and cast iron is removed from the bottom, in which wind, e.g. Air - optionally with additional oxygen, is supplied and the so-called blast furnace gas is discharged in the upper shaft area, the furnace shaft moving from top to bottom into a loading zone (5), a preheating zone (4), a melting zone (3), a wind zone (2) and a hearth zone (1) can be divided and in which a carbon gas carbon monoxide and / or carbon dioxide is fed to the furnace shaft.
  • wind e.g. Air - optionally with additional oxygen
  • a cupola furnace is fed with an insert of 500 kg, which is composed of 440 kg of pig iron and scrap, 47 kg of coke and 13 kg of additives, for example limestone.
  • This insert gradually decreases in the shaft of the cupola furnace and heats up in the preheating zone due to the gases flowing in countercurrent, which initially causes the thermal dissociation of the aggregates, i.e. that of the limestone according to the equation, at approx. 900 to 1000 ° C CaCO3 ---> CaO + CO2 he follows.
  • the melting of the iron insert then begins in the melting zone adjoining the preheating zone. The temperatures there are of the order of approx.
  • This carbon monoxide is important for the function and product quality of the cupola furnace, since it counteracts the burn-off of the insert iron, i.e. the formation of FeO, and also has an advantageous effect on the slag basicity.
  • the object of the present invention is therefore to provide a possibility (s) of being able to influence the carbon monoxide content in cupola furnaces, regardless of The level of the coke in the furnace and the amount of coke in the oven vary and can be set to a certain desired value.
  • This object is achieved according to the invention in that in order to set a desired, increased carbon monoxide content in the upper cupola region, carbon dioxide (CO2) is introduced in the wind zone in the wind zone (2) of the cupola in a suitable amount.
  • CO2 carbon dioxide
  • Another advantageous variant of the method according to the invention is that the carbon dioxide is introduced in the wind zone in a quantity-controlled manner, so that an approximately constant carbon monoxide level is achieved in the cupola furnace.
  • the regulation of an approximately constant level of CO can be achieved in that the carbon dioxide addition is increased accordingly with decreasing filling coke height.
  • a carbon dioxide addition is carried out in an order of magnitude which permits a reduction in the amount of coke.
  • gas supply quantities in the order of 30 to 500 m3 per hour, depending on the size of the coke reduction and the size of the furnace. In this way, savings on batch coke in the order of 1 to 3% are possible with the further advantage that melting capacity increases are achieved, because according to the Jungblut network diagram, less batch coke means a higher melting capacity.
  • the simultaneous supply of carbon dioxide and carbon monoxide can also be favorable. Since CO2 introduced in the wind zone of a cupola furnace acts as a cooling gas, a simultaneous addition of carbon monoxide to the carbon dioxide supply can be advantageous if the cooling effect is too strong, because CO burns in the wind zone, thus providing energy and at the same time increasing the amount of carbon dioxide, which in turn is available for reduction.
  • the carbon gases are provided in storage containers for the applications according to the invention reliably, with a constant composition and with optimal meterability.
  • a sometimes beneficial option is there in that the coal gases, especially carbon dioxide, are obtained from burner exhaust gases, in particular the exhaust gases from the cupola recuperator burner, and thus provide at least part of the gas quantity required.
  • the figure shows a cupola furnace on which an embodiment of the invention is shown.
  • a cupola shaft 11 with a loading opening 12, a top stage 13, a wind ring 14 with wind nozzles 15a and 15b, a bottom flap 16 as well as an iron tapping 17 and a slag tapping 18 is shown.
  • the numbers 1 to 5 and the corresponding dashed lines indicate the generic zone 5, the preheating zone 4, the melting zone 3, the wind zone 2 and finally the oven zone 1.
  • Lances 20a, b are arranged in the wind nozzles 15a and 15b for the furnace wind and are connected to an oxygen supply and a carbon dioxide supply outside the furnace.
  • a cupola furnace operation is now carried out, in which an application as described in the introduction is used. Only the amount of coke is significantly reduced and is significantly lower at around 37 kg (around 7% of the operating weight). 200 m3 of carbon dioxide per hour are now fed to the cupola furnace on lances 20a and 20b. With around 10 sets of insert that pass through the furnace per hour, this corresponds to a gas volume of 20 m3 per insert. The main part of the resulting from the coke in the oven Carbon dioxide is thus replaced by the direct supply of carbon dioxide gas.
  • the gas supply can be carried out constantly with little equipment - installation of a valve and a flow meter in the carbon dioxide supply.
  • a gas supply for example of the sawtooth type, which is synchronized with the addition of the inserts, is also comparatively simple, whereby starting from a lowest supply value shortly after the furnace has been charged with a new insert, the gas quantity is increased linearly up to a maximum value for the next loading, although the total the same amount of gas is maintained as with constant supply.
  • oxygen can likewise be supplied via the lances 20a and b, the amount of wind correspondingly reduced accordingly and thus higher furnace temperatures can be maintained in spite of the reduction in coke and the addition of carbon dioxide.
  • coal gas proposed according to the invention results in a further parameter in cupola furnace operation, with which the processes taking place in a cupola furnace can be advantageously influenced in many ways.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Secondary Cells (AREA)

Abstract

The invention relates to a process for running a cupola furnace for the production of cast iron. When running a cupola furnace, formation of CO, accompanied by advantages, occurs in the cupola furnace, above all in the fusion zone. This formation of CO varies with the coke filling level and, in certain operating cases, reaches undesirably low values. In order to counteract this, it is proposed that a coal gas (CO2 or CO) is introduced at a suitable rate into the cupola furnace at a suitable point, preferably in the region of the air inlet zone or fusion zone. <IMAGE>

Description

Die Erfindung betrifft ein Verfahren zum Betreiben eines Kupolofens zur Erzeugung von Gußeisen,bei dem der Ofenschacht des Kupolofens mit einem entsprechenden Einsatz gefüllt ist bzw. ständig nachgefüllt wird und bodenseitig Gußeisen entnommen wird, bei dem dem Ofenschacht im unteren Bereich Wind, z.B. Luft - gegebenenfalls mit Zusatzsauerstoff, zugeführt wird und im oberen Schachtbereich das sogenannte Gichtgas abgeführt wird, wobei der Ofenschacht von oben nach unten in eine Beschickungszone (5), eine Vorwärmzone (4), eine Schmelzzone(3), eine Windzone (2) und eine Herdzone (1) einteilbar ist und bei dem dem Ofenschacht ein Kohlengas Kohlenmonoxid und/oder Kohlendioxid zugeführt wird.The invention relates to a method for operating a cupola furnace for the production of cast iron, in which the furnace shaft of the cupola furnace is filled with a corresponding insert or is constantly refilled and cast iron is removed from the bottom, in which wind, e.g. Air - optionally with additional oxygen, is supplied and the so-called blast furnace gas is discharged in the upper shaft area, the furnace shaft moving from top to bottom into a loading zone (5), a preheating zone (4), a melting zone (3), a wind zone (2) and a hearth zone (1) can be divided and in which a carbon gas carbon monoxide and / or carbon dioxide is fed to the furnace shaft.

Ein Verfahren, wie es im einleitenden Absatz beschrieben ist, ist aus der US-PS 4 309 024 bekannt. Derzufolge wird speziell ein Kohlenmonoxid enthaltendes Heißgas, das in einem spezifischen, zugehörigen Generator erzeugt wird, in den Bodenbereich eines Kupolofens zu Heizzwecken eingeführt.A method as described in the introductory paragraph is known from US Pat. No. 4,309,024. Accordingly, a hot gas containing carbon monoxide, which is generated in a specific, associated generator, is specifically introduced into the bottom region of a cupola furnace for heating purposes.

Im allgemein bekannten Standardbetrieb wird ein Kupolofen beispielsweise mit einem Einsatz von 500 kg beschickt, der sich aus 440 kg Roheisen und Schrott, 47 kg Koks und 13 kg Zuschlagstoffen, z.B. Kalksteinen, zusammensetzt. Dieser Einsatz sinkt nach und nach im Schacht des Kupolofens ab, erwärmt sich dabei in der Vorwärmzone durch die im Gegenstrom zum Einsatz fließenden Gase, wodurch bei ca. 900 bis 1000°C zunächst die thermische Dissoziation der Zuschlagstoffe, also die des Kalksteins gemäß der Gleichung



        CaCO₃ ---> CaO + CO₂



erfolgt. In der sich an die Vorwärmzone anschließenden Schmelzzone beginnt dann das Schmelzen des Eiseneinsatzes. Die Temperaturen dort sind in der Größenordnung von ca. 1400°C und der im Einsatz befindliche Koks ist in dieser Ofenzone bereits weißglühend. Dessen Verbrennung erfolgt jedoch erst in der noch tiefer liegenden Windzone des Kupolofens, da erst dort der zur Verbrennung notwendige Sauerstoff vorhanden ist. Aus der Verbrennung des Kokses gemäß der Gleichung



        C + O₂ ---> CO₂



geht Kohlendioxid hervor, das mit dem von der Windzufuhr herrührenden Gasstrom im Ofen weitertransportiert wird. Dieses Kohlendioxid durchläuft beim Aufsteigen im Kupolofen die höher liegende Schmelzzone und wird in dieser von dem glühenden, dort noch nicht verbrannten Koks gemäß Boudouard Reaktion reduziert, wodurch Kohlenmonoxid (CO) entsteht:



        CO₂ + C <--->2CO.


In the well-known standard operation, for example, a cupola furnace is fed with an insert of 500 kg, which is composed of 440 kg of pig iron and scrap, 47 kg of coke and 13 kg of additives, for example limestone. This insert gradually decreases in the shaft of the cupola furnace and heats up in the preheating zone due to the gases flowing in countercurrent, which initially causes the thermal dissociation of the aggregates, i.e. that of the limestone according to the equation, at approx. 900 to 1000 ° C



CaCO₃ ---> CaO + CO₂



he follows. The melting of the iron insert then begins in the melting zone adjoining the preheating zone. The temperatures there are of the order of approx. 1400 ° C and the coke in use is already incandescent in this zone. However, its combustion only takes place in the wind zone of the cupola furnace, which is even lower, since the oxygen necessary for combustion is only available there. From burning the coke according to the equation



C + O₂ ---> CO₂



carbon dioxide is produced, which is transported further in the furnace with the gas stream resulting from the wind supply. This carbon dioxide passes through the higher melting zone when it rises in the cupola furnace and is reduced in it by the glowing coke, which has not yet burned there, in accordance with the Boudouard reaction, which produces carbon monoxide (CO):



CO₂ + C <---> 2CO.


Dieses Kohlenmonoxid wiederum ist für die Funktion und Produktqualität des Kupolofens wichtig, da es dem Abbrand des Einsatzeisens, also der FeO-Bildung, entgegenwirkt und auch eine vorteilhafte Wirkung bezüglich der Schlackebasizität besitzt.This carbon monoxide, in turn, is important for the function and product quality of the cupola furnace, since it counteracts the burn-off of the insert iron, i.e. the formation of FeO, and also has an advantageous effect on the slag basicity.

Hierbei ist zu berücksichtigen, daß die Kohlenmonoxid Bildung in der Schmelzzone stark vom Füllstand des Füllkokses in der Kupolofensäule abhängt und diese im Gleichgewicht mit dem Satzkoksanteil steht. D.h. niedriger Füllkoksstand und ggfs. niedriger Satzkoksanteil bedingen einen sehr niedrigen Kohlenmonoxid Gehalt im oberen Kupolofenbereich. In der Folge sind auch die oben ausgeführten, vorteilhaften Effekte nicht mehr gewährleistet. Dies gilt heute umso mehr, als durch die ökonomisch immer weiter verbesserten Kupolofenanlagen ohnehin vergleichsweise niedrige Satzkoksanteile möglich sind.It must be taken into account here that the formation of carbon monoxide in the melting zone is strongly dependent on the filling level of the filling coke in the cupola furnace column and that this is in equilibrium with the batch coke content. I.e. low filling coke level and possibly low batch coke content result in a very low carbon monoxide content in the upper cupola furnace area. As a result, the advantageous effects set out above are no longer guaranteed. This is all the more true today, since the economically continuously improved cupola furnace systems make comparatively low coke levels possible.

Die Aufgabenstellung vorliegender Erfindung besteht daher darin, eine Möglichkeit(en) anzugeben, den Kohlenmonoxid Gehalt in Kupolöfen beeinflussen zu können, diesen unabhängig vom Füllstand des Kokses im Ofen und vom Anteil des Satzkokses variieren und auf einen bestimmten gewünschten Wert einstellen zu können.The object of the present invention is therefore to provide a possibility (s) of being able to influence the carbon monoxide content in cupola furnaces, regardless of The level of the coke in the furnace and the amount of coke in the oven vary and can be set to a certain desired value.

Diese Aufgabe wird gemäß der Erfindung dadurch gelöst, daß zur Einstellung eines gewünschten, erhöhten Kohlenmonoxid Gehalts im oberen Kupolofenbereich Kohlendioxid (CO₂) in der Windüsenebene in die Windzone (2) des Kupolofens in geeigneter Menge eingebracht wird.This object is achieved according to the invention in that in order to set a desired, increased carbon monoxide content in the upper cupola region, carbon dioxide (CO₂) is introduced in the wind zone in the wind zone (2) of the cupola in a suitable amount.

Durch diese Kohlendioxid Zugabe wird dem in der Windzone durch die Verbrennung von Koks entstehenden Kohlendioxid Gas ein weiterer Anteil Kohlendioxid hinzugefügt und aus dem so vergrößerten CO₂-Angebot in der Schmelzzone, in der ja eine Kohlendioxid Reduktion gemäß der Boudouard Reaktion erfolgt, eine größere Menge Kohlenmonoxid erzeugt. In der Folge steigt das Kohlenmonoxid Niveau im Ofen mit den positiven Wirkungen wie Abbrandvermeidung und vorteilhafter Schlackenbildung. Beispielsweise ist die konstante Zufuhr von Kohlendioxid Gas in die Windzone des Kupolofens bereits eine günstige Variante des erfindunsgemäßen Verfahrens.Through this addition of carbon dioxide, a further portion of carbon dioxide is added to the carbon dioxide gas produced in the wind zone by the burning of coke, and a larger amount of carbon monoxide from the increased CO₂ supply in the melting zone, in which a carbon dioxide reduction takes place according to the Boudouard reaction generated. As a result, the carbon monoxide level in the furnace rises with the positive effects such as preventing burn-off and advantageous slag formation. For example, the constant supply of carbon dioxide gas into the wind zone of the cupola furnace is already a cheap variant of the method according to the invention.

Eine andere vorteilhafte Variante des erfindungsgemäßen Verfahrens besteht darin, daß das Kohlendioxid in der Windzone in mengengeregelter Weise eingebracht wird, so daß ein etwa gleichbleibendes Kohlenmonoxid Niveau im Kupolofen erzielt wird. Die Einregelung eines etwa gleichbleibenden Niveaus an CO kann dadurch erreicht werden, daß mit abnehmender Füllkokshöhe die Kohlendioxid Zugabe entsprechend erhöht wird.Another advantageous variant of the method according to the invention is that the carbon dioxide is introduced in the wind zone in a quantity-controlled manner, so that an approximately constant carbon monoxide level is achieved in the cupola furnace. The regulation of an approximately constant level of CO can be achieved in that the carbon dioxide addition is increased accordingly with decreasing filling coke height.

In einer weiteren und weitergehenden Erfindungsvariante wird eine Kohlendioxid Zugabe in einer Größenordnung durchgeführt wird, die eine Absenkung der Satzkoksmenge zuläßt. Dabei handelt es sich um Gaszufuhrmengen in der Größenordnung von 30 bis 500 m³ pro Stunde, abhängig von der Größe der Satzkoksreduzierung und der Ofengröße. Auf diese Weise werden Einsparungen an Satzkoks in einer Größenordnung von 1 bis 3 % mit dem weiteren Vorteil möglich, daß Schmelzleistungserhöhungen erzielt werden, denn nach dem Netzdiagramm von Jungblut bedeutet weniger Satzkoks eine höhere Schmelzleistung.In a further and further variant of the invention, a carbon dioxide addition is carried out in an order of magnitude which permits a reduction in the amount of coke. These are gas supply quantities in the order of 30 to 500 m³ per hour, depending on the size of the coke reduction and the size of the furnace. In this way, savings on batch coke in the order of 1 to 3% are possible with the further advantage that melting capacity increases are achieved, because according to the Jungblut network diagram, less batch coke means a higher melting capacity.

Erfindungemäß kann auch die gleichzeitige Zufuhr von Kohlendioxid und Kohlenmonoxid günstig sein. Da in der Windzone eines Kupolofens eingebrachtes CO₂ als Kühlgas wirkt, kann, bei zu starker Kühlwirkung, eine gleichzeitige Kohlenmonoxid Zugabe zur Kohlendioxid Zufuhr vorteilhaft sein, denn CO verbrennt in der Windzone, liefert also Energie und erhöht gleichzeitig so auch die Kohlendioxid Menge, die wiederum zur Reduktion zur Verfügung steht.According to the invention, the simultaneous supply of carbon dioxide and carbon monoxide can also be favorable. Since CO₂ introduced in the wind zone of a cupola furnace acts as a cooling gas, a simultaneous addition of carbon monoxide to the carbon dioxide supply can be advantageous if the cooling effect is too strong, because CO burns in the wind zone, thus providing energy and at the same time increasing the amount of carbon dioxide, which in turn is available for reduction.

Zuverlässig, mit gleichbleibender Zusammensetzung und mit optimaler Dosierbarkeit werden die Kohlengase in Speicherbehältern für die erfindungsgemäßen Anwendungen bereitgestellt. Eine manchmal vorteilhafte Möglichkeit besteht darin, die Kohlengase, vor allem Kohlendioxid, aus Brennerabgasen, insbesondere den Abgasen des Kupolofen-Rekuperator-Brenners, zu gewinnen und so zumindest ein Teil der benötigten Gasmenge bereitzustellen.The carbon gases are provided in storage containers for the applications according to the invention reliably, with a constant composition and with optimal meterability. A sometimes beneficial option is there in that the coal gases, especially carbon dioxide, are obtained from burner exhaust gases, in particular the exhaust gases from the cupola recuperator burner, and thus provide at least part of the gas quantity required.

Anhand der Figur soll beispielhaft die Erfindung näher erläutert werden.The invention will be explained in more detail by way of example with reference to the figure.

Die Figur zeigt einen Kupolofen, an dem eine Ausführung der Erfindung gezeigt ist. Zunächst ist ein Kupolofenschacht 11 mit einer Beschickungsöffnung 12, einer Gichtbühne 13, einem Windring 14 mit Winddüsen 15a und 15b, einer Bodenklappe 16 sowie einem Eisenabstich 17 und einem Schlackenabstich 18 gezeigt.The figure shows a cupola furnace on which an embodiment of the invention is shown. First of all, a cupola shaft 11 with a loading opening 12, a top stage 13, a wind ring 14 with wind nozzles 15a and 15b, a bottom flap 16 as well as an iron tapping 17 and a slag tapping 18 is shown.

Innerhalb des Ofens sind mit den Ziffern 1 bis 5 sowie zugehörigen gestrichelten Linien die Gattierungszone 5, die Vorwärmzone 4, die Schmelzzone 3, die Windzone 2 und letztlich die Herdzone 1 angedeutet.Within the oven, the numbers 1 to 5 and the corresponding dashed lines indicate the generic zone 5, the preheating zone 4, the melting zone 3, the wind zone 2 and finally the oven zone 1.

In den Winddüsen 15a und 15b für den Ofenwind sind Lanzen 20a,b angeordnet, die außerhalb des Ofens mit einer Sauerstoffversorgung und einer Kohlendioxidversorgung verbunden sind.Lances 20a, b are arranged in the wind nozzles 15a and 15b for the furnace wind and are connected to an oxygen supply and a carbon dioxide supply outside the furnace.

Erfindungsgemäß wird nun ein Kupolofenbetrieb durchgeführt, bei dem ein Einsatz, wie er in der Einleitung beschrieben ist, eingesetzt wird. Lediglich die Satzkoksmenge ist wesentlich reduziert und liegt mit ca 37 kg (ca. 7% vom Einsatzgewicht) deutlich niedriger. In der Windüsenebene werden dem Kupolofen über die Lanzen 20a und 20b jetzt 200 m³ Kohlendioxid pro Stunde zugeführt. Das entspricht bei ca 10 Sätzen Einsatz, die den Ofen pro Stunde durchlaufen, einer Gasmenge von 20 m³ pro Einsatz. Der Hauptteil des aus dem Satzkoks im Ofen entstehenden Kohlendioxid wird so durch unmittelbare Zufuhr von Kohlendioxid Gas ersetzt.Die Gaszufuhr kann mit geringem apparativem Aufwand - Installation eines Ventils und eines Durchflussmessers in die Kohlendioxid Zufuhr - konstant ausgeführt werden. Auch eine mit der Zugabe der Einsätze synchronisierte Gaszufuhr etwa vom Sägezahntyp ist vergleichsweise einfach, wobei ausgehend von einem niedrigsten Zufuhrwert kurz nach der Beschickung des Ofens mit einem neuen Einsatz die Gasmenge linear bis zu einem Höchstwert bei der nächsten Beschickung gesteigert wird, wobei jedoch insgesamt die gleiche Gasmenge wie bei konstanter Zufuhr eingehalten wird. Zudem kann beim gezeigten Kupolofen Sauerstoff ebenfalls über die Lanzen 20a und b zugeführt werden, die Windemenge in Korrelation damit geeignet reduziert werden und so höhere Ofentemperaturen trotz Satzkoksreduzierung und Kohlendioxid Zugabe aufrechterhalten werden.According to the invention, a cupola furnace operation is now carried out, in which an application as described in the introduction is used. Only the amount of coke is significantly reduced and is significantly lower at around 37 kg (around 7% of the operating weight). 200 m³ of carbon dioxide per hour are now fed to the cupola furnace on lances 20a and 20b. With around 10 sets of insert that pass through the furnace per hour, this corresponds to a gas volume of 20 m³ per insert. The main part of the resulting from the coke in the oven Carbon dioxide is thus replaced by the direct supply of carbon dioxide gas. The gas supply can be carried out constantly with little equipment - installation of a valve and a flow meter in the carbon dioxide supply. A gas supply, for example of the sawtooth type, which is synchronized with the addition of the inserts, is also comparatively simple, whereby starting from a lowest supply value shortly after the furnace has been charged with a new insert, the gas quantity is increased linearly up to a maximum value for the next loading, although the total the same amount of gas is maintained as with constant supply. In addition, in the cupola furnace shown, oxygen can likewise be supplied via the lances 20a and b, the amount of wind correspondingly reduced accordingly and thus higher furnace temperatures can be maintained in spite of the reduction in coke and the addition of carbon dioxide.

Ingesamt ergibt sich mit der erfindungsgemäß vorgeschlagenen Kohlengaszugabe ein weitere Parameter im Kupolofenbetrieb, mit dem auf vielfache Weise vorteilhaft auf die in einem Kupolofen ablaufenden Prozesse eingewirkt werden kann.Overall, the addition of coal gas proposed according to the invention results in a further parameter in cupola furnace operation, with which the processes taking place in a cupola furnace can be advantageously influenced in many ways.

Claims (7)

  1. Method for the operation of a cupola furnace for the production of cast iron,
    - wherein the furnace shaft of the cupola furnace is filled or continuously refilled with a corresponding charge and cast iron is removed at the bottom end,
    - wherein a blast, e.g. air - possibly with additional oxygen - is introduced into the furnace shaft in the lower area and the so-called throat gas is removed in the upper area of the shaft, the furnace shaft being divisible from the top to the bottom into a charging zone (5), a pre-heating zone (4), a melting zone (3), a blast zone (2) and a hearth zone (1),
    - and wherein a carbon gas (carbon monoxide and/or carbon dioxide) is introduced into the furnace shaft, characterised in that level with the blast nozzles, carbon dioxide (CO₂) is introduced into the blast zone (2) of the cupola furnace in a suitable quantity to produce a desired increased level of carbon monoxide in the upper area of the cupola furnace.
  2. Method according to claim 1, characterised in that the carbon dioxide is introduced in a constant quantity.
  3. Method according to claim 1, characterised in that the carbon dioxide is introduced in controlled quantities such that an essentially constant level of carbon monoxide is obtained in the cupola furnace, for example the gas is introduced synchronised with the introduction of the charges following an essentially saw tooth pattern.
  4. Method according to claims 1 to 3, characterised in that the carbon dioxide is introduced in a quantity which allows a reduction in the quantity of charging coke.
  5. Method according to claims 1 to 4, characterised in that carbon monoxide is also introduced at the same time as carbon dioxide is introduced.
  6. Method according to claims 1 to 3, characterised in that the carbon dioxide is kept in storage containers.
  7. Method according to claims 1 to 3, characterised in that the carbon dioxide is obtained at least partially from burner waste gases, in particular from the waste gases of the cupola furnace recovery unit burner.
EP92111337A 1991-07-05 1992-07-03 Process for running a cupola Expired - Lifetime EP0521523B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4122381A DE4122381A1 (en) 1991-07-05 1991-07-05 METHOD FOR OPERATING A COUPLING OVEN
DE4122381 1991-07-05

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EP0521523A1 EP0521523A1 (en) 1993-01-07
EP0521523B1 true EP0521523B1 (en) 1995-09-06

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AT (1) ATE127580T1 (en)
DE (2) DE4122381A1 (en)
ES (1) ES2079744T3 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19509366A1 (en) * 1995-03-15 1996-09-19 Linde Ag Iron recovery from dust, esp. fettling dust
PL183679B1 (en) * 1995-08-28 2002-06-28 Linde Gas Ag Method of operating a shaft furnace with oxygen admission and shaft furnace with oxygen admission
DE10117962B4 (en) * 2001-04-10 2006-12-07 At.Pro Tec Technologie-Team Gmbh Process for the thermal treatment of raw materials and for carrying out the process
DE102007025663A1 (en) * 2007-06-01 2008-12-04 Linde Ag Process for controlled coke conversion in cupola furnaces
CN101428342B (en) * 2008-12-18 2013-02-13 高尔荣 Ironmaking casting system

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE930930C (en) * 1950-06-10 1955-07-28 Heinrich Dr Ing E H Koppenberg Process for operating a shaft furnace with highly concentrated oxygen
DE1132570B (en) * 1955-03-28 1962-07-05 Ruhrstahl Ag Process for operating blast furnaces, in particular low-shaft furnaces
US3630719A (en) * 1969-04-01 1971-12-28 Chemical Construction Corp Method of operating a cupola furnace
DE2315748A1 (en) * 1973-03-29 1974-12-19 Wests Manchester Ltd Gas fired vertical furnace - with exhaust partly recycled to burners to produce even combustion
US4309024A (en) * 1977-07-18 1982-01-05 Modern Equipment Company Cupola with auxiliary gas generator

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DE59203547D1 (en) 1995-10-12
EP0521523A1 (en) 1993-01-07
ATE127580T1 (en) 1995-09-15
ES2079744T3 (en) 1996-01-16
DE4122381A1 (en) 1993-01-07

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