EP1234889A1 - Apparatus for granulating of liquid slag - Google Patents
Apparatus for granulating of liquid slag Download PDFInfo
- Publication number
- EP1234889A1 EP1234889A1 EP02450031A EP02450031A EP1234889A1 EP 1234889 A1 EP1234889 A1 EP 1234889A1 EP 02450031 A EP02450031 A EP 02450031A EP 02450031 A EP02450031 A EP 02450031A EP 1234889 A1 EP1234889 A1 EP 1234889A1
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- EP
- European Patent Office
- Prior art keywords
- cooling
- centrifugal wheel
- space
- tundish
- slag
- Prior art date
- 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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Links
- 239000002893 slag Substances 0.000 title claims abstract description 25
- 239000007788 liquid Substances 0.000 title claims abstract description 6
- 238000001816 cooling Methods 0.000 claims abstract description 22
- 239000007921 spray Substances 0.000 claims abstract description 3
- 239000000155 melt Substances 0.000 claims description 17
- 239000002826 coolant Substances 0.000 claims description 8
- 229930195733 hydrocarbon Natural products 0.000 claims description 3
- 150000002430 hydrocarbons Chemical class 0.000 claims description 3
- 238000002347 injection Methods 0.000 claims description 2
- 239000007924 injection Substances 0.000 claims description 2
- 230000005855 radiation Effects 0.000 claims description 2
- 238000004544 sputter deposition Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 14
- 230000015572 biosynthetic process Effects 0.000 description 9
- 238000002844 melting Methods 0.000 description 8
- 230000008018 melting Effects 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 239000003380 propellant Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 238000000889 atomisation Methods 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 238000005469 granulation Methods 0.000 description 2
- 230000003179 granulation Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 208000012868 Overgrowth Diseases 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000007908 dry granulation Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000011344 liquid material Substances 0.000 description 1
- 239000012768 molten material Substances 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- JTJMJGYZQZDUJJ-UHFFFAOYSA-N phencyclidine Chemical class C1CCCCN1C1(C=2C=CC=CC=2)CCCCC1 JTJMJGYZQZDUJJ-UHFFFAOYSA-N 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B3/00—General features in the manufacture of pig-iron
- C21B3/04—Recovery of by-products, e.g. slag
- C21B3/06—Treatment of liquid slag
- C21B3/08—Cooling slag
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/02—Physical or chemical treatment of slags
- C21B2400/022—Methods of cooling or quenching molten slag
- C21B2400/024—Methods of cooling or quenching molten slag with the direct use of steam or liquid coolants, e.g. water
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/05—Apparatus features
- C21B2400/052—Apparatus features including rotating parts
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/05—Apparatus features
- C21B2400/052—Apparatus features including rotating parts
- C21B2400/054—Disc-shaped or conical parts for cooling, dispersing or atomising of molten slag rotating along vertical axis
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/05—Apparatus features
- C21B2400/062—Jet nozzles or pressurised fluids for cooling, fragmenting or atomising slag
Definitions
- the invention relates to a device for atomization and granulating melts, especially liquid ones Slag, with a spray head at a tundish outlet with a centrifugal wheel that can be driven to rotate, the axis of rotation of which in the direction of the axis of the tundish outlet escaping slag stream runs, as well as a cooling room connected.
- AT 407 247 has already proposed a melt ejecting from a melt tundish with fluid under pressure, where in particular pressurized gas, steam or pressurized water in Pressed in the direction of the slag outlet from the tundish has been.
- the slag tundish outlet requires such Training special measures to prevent the Outlet opening freezes and it was therefore proposed to height-adjustable weir pipe in the area of the slag outlet into the tundish to reduce the amount flowing out to be able to regulate, the propellant gas jet coaxial to Axis of the outlet opening was introduced and the tundish outlet opens directly into the refrigerator.
- AT 405 511 describes a process for granulating and comminuting described by molten material, in which liquid slag in free fall with pressurized water jets is applied, whereupon the solidified and granulated Slag together with the steam formed via a pneumatic Delivery line and a distributor is guided. That on this way distributed material can be immediately in a Jet mill to be further crushed.
- the basic processes when granulating and crushing molten liquid Material by applying steam is also in EP 683 824 B1 already described, a mixing chamber being provided here is in which water, water vapor and / or air-water mixtures be injected, whereupon the evaporated water together ejected with the solidified material via a diffuser becomes.
- the atomizer head is of such a design designed as a mixing chamber with a subsequent diffuser, in this case, too, molten slag a corresponding storage vessel or a tundish can be.
- AT 407 152 B uses solid material in a melting cyclone melted, being on the flameproof closable Melt cyclone is directly connected to a cold room, which subsequently under less pressure than the melting cyclone must be kept to prevent the material from exiting the Allow melting cyclone in the cold room.
- the required heat of fusion in Melting cyclone must be applied during combustion generates a large amount of gas from fuels in the melting cyclone, which subsequently requires a correspondingly complex cleaning.
- a regulation of such a method is only in the extent possible to the extent that the corresponding Heat of fusion is provided, so in particular a reduction in the amount of gas produced and an adjustment to the desired cooling conditions within the scope of such Melting cyclones cannot be achieved.
- the invention now aims to provide a device for atomizing melts, in which much smaller particle sizes can be achieved than with conventional granulation and in which the amount of gas generated in the process or required for the operation of the process can be kept low.
- the inventive device of the type mentioned essentially consists in that the cooling space is designed as an annular space concentrically surrounding the centrifugal wheel and is connected to the centrifugal wheel with the interposition of a heatable annular chamber.
- the melt with the interposition of a conventional melt flow control element, such as a feeder or tundish stopper, reaches a centrifugal wheel whose axis of rotation essentially coincides with the axis of the tundish outlet, an extremely small-scale device is created, in which the centrifugal wheel comminutes the melt flow as a function of the speed of rotation, appropriate coolants being installed in the radially adjoining space.
- the device is thus constructed as an essentially annular chamber, which only requires a small overall height and the manipulation of the melts is correspondingly simplified, since the melt no longer has to be raised, as in conventional steam atomizing nozzles, in order to be ejected into an underlying space become.
- centrifugal wheel with a subsequent annular cooling chamber thus constitutes an extremely small construction, in which nevertheless important process parameters, which are relevant for the formation of suitable particle sizes, can be set within wide limits and with simple means.
- process parameters which are relevant for the formation of suitable particle sizes
- the design according to the invention is advantageously made such that the tundish outlet is connected to the centrifugal wheel and the annular space via a heatable connecting pipe.
- the slag can still be overheated with burners or hot gas and in particular at temperatures from 1400 ° to 1800 ° C., so that the formation of very fine droplets is ensured by the centrifugal wheel.
- the impeller itself can have a corresponding controllable drive, for example, in the speed range from 3,000 to 20,000 min -1, to be operated.
- the design is advantageously made such that burners open into the connecting pipe.
- the training according to the invention is such that the annular space designed as a cooling space with interposition a heated ring chamber connected to the centrifugal wheel is.
- the cooling chamber designed as an annular chamber can be conventional Way cooled and it can be training in particular be made for this purpose so that the radially extending walls of the cold room double-walled as Radiation cooling surfaces are formed on the cavity Lines for cooling medium are connected.
- the dimensions of one Such a cooling chamber can also be used further decrease if media enters the cooling chamber immediately are injected, which are, for example, under high Decompose enthalpy consumption. Training is an advantage therefore taken so that the annular space designed as a cooling space Connections for the injection of coolants, e.g. hydrocarbons, has in the annulus.
- 1 denotes a melt tundish, whose melt outflow regulator 2 is designed as a feeder and by lifting in the direction of the double arrow 3 a corresponding one Regulation of the melt stream flowing out 4 enables.
- a connection tube 5 is connected pressure-tight to this tundish 1, in which hot gas is blown in via ring nozzles 6 and 7 becomes.
- burners can be used open into the shaft formed by the transition pipe 5, so that the slag jet 4 accordingly up to temperatures can be overheated to 1800 ° C.
- annular chamber 8 is connected, which consists of several sections consists.
- a centrifugal wheel 9 rotatably mounted, the axis of rotation 10 essentially with the axis 11 of the tundish outlet flees. The melt or slag thus meets this rotating centrifugal wheel 9 and is in the radial direction in the annular chamber 8 flung outwards.
- the outer area of the Annular chamber 8 is designed as an annular cooling chamber 13, whose walls are double-walled. In between the cavity 14 enclosed in the walls can do the same Coolant be introduced.
- nozzles 15 are provided through which, for example, hydrocarbons are injected which, with strong endothermic decomposition, the fine The melt droplets quickly withdraw heat and in this way ensure safe solidification and cooling.
- microgranules formed leave the annular cooling chamber on the circumference of the same, in particular with temperatures between 200 ° and 500 ° C and can be collected outside the annulus become.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Iron (AREA)
- Fertilizers (AREA)
- Coating By Spraying Or Casting (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Glanulating (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
Description
Die Erfindung bezieht sich auf eine Einrichtung zum Zerstäuben und Granulieren von Schmelzen, insbesondere flüssigen Schlacken, bei welcher an einen Tundishauslauf ein Sprühkopf mit einem zur Rotation antreibbaren Schleuderrad, dessen Rotationsachse in Richtung der Achse des aus dem Tundishauslauf austretenden Schlackenstrahles verläuft, sowie ein Kühlraum angeschlossen ist.The invention relates to a device for atomization and granulating melts, especially liquid ones Slag, with a spray head at a tundish outlet with a centrifugal wheel that can be driven to rotate, the axis of rotation of which in the direction of the axis of the tundish outlet escaping slag stream runs, as well as a cooling room connected.
In der AT 407 247 wurde bereits vorgeschlagen, eine Schmelze aus einem Schmelzentundish mit Fluid unter Druck auszustossen, wobei hier insbesondere Druckgas, Dampf oder Druckwasser in Richtung des Schlackenaustritts aus dem Tundish eingepreßt wurde. Der Schlackentundishauslauf erfordert bei derartigen Ausbildungen besondere Maßnahmen um zu verhindern, daß die Auslauföffnung zufriert und es wurde daher vorgeschlagen, ein höhenverstellbares Wehrrohr im Bereich des Schlackenauslaufes in den Tundish abzusenken, um die jeweils ausströmende Menge regulieren zu können, wobei der Treibgasstrahl koaxial zur Achse der Auslauföffnung eingebracht wurde und der Tundishauslauf unmittelbar in den Kühlraum mündet. Bei einer derartigen Ausbildung des Zerstäuberkopfes als Düse, in welche koaxial der Strahl einer Treibgaslanze mündet, muß in der Regel ein hoch überhitzter Dampf eingesetzt werden, um ein Zuwachsen der Öffnung zu verhindern, wobei je nach Zusammensetzung der Schmelze und insbesondere bei höherem Eisenoxidgehalt der Schmelze auch hohe Anforderungen an das Feuerfestmaterial gestellt werden. Analoges gilt für die Ausbildung des höhenverstellbaren Wehrrohres, welches bei aggressiven Schmelzen einem hohen Verschleiß unterworfen ist und daher eine aufwendige Regelung für die korrekte Einstellung der Höhenlage des Wehrrohres erfordert. Neben einer derartigen Ausbildung des Zerstäuberkopfes als Austrittsdüse aus einem Schlackentundish sind weitere Ausbildungen beispielsweise der AT 406 954 B zu entnehmen, wobei hier die flüssige Schlacke in eine unter Unterdruck stehende Expansionskammer eingesaugt wird und mit einem Treibstrahl in die Kühlzone transportiert wird. AT 407 247 has already proposed a melt ejecting from a melt tundish with fluid under pressure, where in particular pressurized gas, steam or pressurized water in Pressed in the direction of the slag outlet from the tundish has been. The slag tundish outlet requires such Training special measures to prevent the Outlet opening freezes and it was therefore proposed to height-adjustable weir pipe in the area of the slag outlet into the tundish to reduce the amount flowing out to be able to regulate, the propellant gas jet coaxial to Axis of the outlet opening was introduced and the tundish outlet opens directly into the refrigerator. With such a Formation of the atomizer head as a nozzle, in which coaxially the jet of a propellant gas lance opens into the Usually a superheated steam can be used to keep an overgrowth to prevent the opening, depending on the composition the melt and especially with a higher iron oxide content the melt also places high demands on the refractory material be put. The same applies to training of the height-adjustable weir pipe, which is used for aggressive Melting is subject to high wear and tear and therefore a complex regulation for the correct setting of the Height of the weir pipe required. In addition to such Formation of the atomizer head as an outlet nozzle from a Slag tundish are further training courses, for example AT 406 954 B, where the liquid slag in an expansion chamber under vacuum is sucked in is transported into the cooling zone with a propellant jet becomes.
In der AT 405 511 ist ein Verfahren zum Granulieren und Zerkleinern von schmelzflüssigem Material beschrieben, bei welchem flüssige Schlacke im freien Fall mit Druckwasserstrahlen beaufschlagt wird, worauf die erstarrte und granulierte Schlacke gemeinsam mit dem gebildeten Dampf über eine pneumatische Förderleitung und einen Verteiler geführt wird. Das auf diese Weise verteilte Material kann unmittelbar in einer Strahlmühle weiter zerkleinert werden. Die prinzipiellen Abläufe beim Granulieren und Zerkleinern von schmelzflüssigem Material durch Beaufschlagen mit Dampf sind auch in der EP 683 824 B1 bereits beschrieben, wobei hier eine Mischkammer vorgesehen ist, in welche Wasser, Wasserdampf und/oder Luft-Wassergemische eingedüst werden, worauf das verdampfte Wasser gemeinsam mit dem erstarrten Material über einen Diffusor ausgestossen wird. Der Zerstäuberkopf ist bei einer derartigen Ausbildung als Mischkammer mit anschließendem Diffusor ausgebildet, wobei auch in diesem Fall schmelzflüssige Schlacke aus einem entsprechenden Vorratsgefäß oder einem Tundish zugeführt werden kann.AT 405 511 describes a process for granulating and comminuting described by molten material, in which liquid slag in free fall with pressurized water jets is applied, whereupon the solidified and granulated Slag together with the steam formed via a pneumatic Delivery line and a distributor is guided. That on this way distributed material can be immediately in a Jet mill to be further crushed. The basic processes when granulating and crushing molten liquid Material by applying steam is also in EP 683 824 B1 already described, a mixing chamber being provided here is in which water, water vapor and / or air-water mixtures be injected, whereupon the evaporated water together ejected with the solidified material via a diffuser becomes. The atomizer head is of such a design designed as a mixing chamber with a subsequent diffuser, in this case, too, molten slag a corresponding storage vessel or a tundish can be.
In der AT 407 152 B wird festes Material in einem Schmelzzyklon erschmolzen, wobei an den druckfest verschließbaren Schmelzzyklon unmittelbar ein Kühlraum angeschlossen ist, welcher in der Folge unter geringerem Druck als der Schmelzzyklon gehalten werden muß, um den Austritt des Materials aus dem Schmelzzyklon in den Kühlraum zu ermöglichen. Da bei einem derartigen Verfahren die erforderliche Schmelzwärme im Schmelzzyklon aufgebracht werden muß, wird bei der Verbrennung von Brennstoffen im Schmelzzyklon eine hohe Gasmenge erzeugt, welche in der Folge eine entsprechend aufwendige Reinigung erfordert. Eine Regelung eines derartigen Verfahrens ist nur in dem Umfang möglich, in dem voraussetzungsgemäß die entsprechende Schmelzwärme bereitgestellt wird, sodaß insbesondere eine Reduktion der produzierten Gasmenge und eine Einstellung an die gewünschten Kühlbedingungen im Rahmen eines derartigen Schmelzzyklones nicht erzielt werden kann. AT 407 152 B uses solid material in a melting cyclone melted, being on the flameproof closable Melt cyclone is directly connected to a cold room, which subsequently under less pressure than the melting cyclone must be kept to prevent the material from exiting the Allow melting cyclone in the cold room. There with one such processes the required heat of fusion in Melting cyclone must be applied during combustion generates a large amount of gas from fuels in the melting cyclone, which subsequently requires a correspondingly complex cleaning. A regulation of such a method is only in the extent possible to the extent that the corresponding Heat of fusion is provided, so in particular a reduction in the amount of gas produced and an adjustment to the desired cooling conditions within the scope of such Melting cyclones cannot be achieved.
All diesen bekannten Ausbildungen gemeinsam ist der Umstand, daß für den Ausstoß der Schlacken hohe Mengen an Treibgasen, insbesondere Dampf eingesetzt werden, wobei Dampf in aller Regel stark überhitzt und Treibgase entsprechend hochvorgewärmt eingesetzt werden müssen. Neben der hohen zu erwärmenden Gasmenge besteht im Anschluß an die Zerstäubung ein relativ hoher Aufwand in der erforderlichen Reinigung der eingesetzten und gebildeten Gase, sodaß der apparative Aufwand für die Gaserzeugung und die Gasreinigung relativ hoch ist.Common to all these well-known training courses is the fact that high quantities of propellant gases for the discharge of the slags, steam in particular are used, steam in all Usually overheated and propellant gases preheated accordingly must be used. In addition to the high to be heated There is a relative amount of gas after atomization high effort in the necessary cleaning of the used and gases formed, so that the equipment required for gas generation and the gas purification is relatively high.
Klassische Granulierverfahren sehen vor; daß Schmelzen bzw. Schlacken einfach in Kühlflüssigkeiten eingeleitet werden, wobei naturgemäß bei Verwendung von Wasser als Kühlflüssigkeit die Schlacken nur geringe Eisenanteile enthalten dürfen, um einen stabilen Betrieb zu gewährleisten. Bei der Trockengranulation gelangt die Schlacke auf Kühlbänder oder Kühlplatten, wofür in der Regel relativ großbauende Einrichtungen erforderlich sind.Classical granulation processes provide; that melting or Slags are simply introduced into coolants, whereby naturally when using water as the coolant the slags may only contain small amounts of iron in order to to ensure stable operation. With dry granulation the slag gets on cooling belts or cooling plates, which usually requires relatively large-scale facilities are.
Die Erfindung zielt nun darauf ab, eine Einrichtung zum Zerstäuben von Schmelzen zu schaffen, bei welcher wesentlich kleinere Teilchengrößen als bei konventioneller Granulation erzielt werden können und bei welcher die im Verfahren erzeugte bzw. für den Betrieb des Verfahrens benötigte Gasmenge gering gehalten werden kann. Zur Lösung dieser Aufgabe besteht die erfindungsgemäße Einrichtung der eingangs genannten Art im wesentlichen darin, daß der Kühlraum als das Schleuderrad konzentrisch umgebender Ringraum ausgebildet und unter Zwischenschaltung einer beheizbaren Ringkammer an das Schleuderrad angeschlossen ist. Dadurch, daß, wie an sich bekannt, die Schmelze unmittelbar unter Zwischenschaltung eines konventionellen Schmelzenflußregelorganes, wie beispielsweise eines Feeders oder Tundishstopfens, auf ein Schleuderrad gelangt, dessen Rotationsachse im wesentlichen mit der Achse des Tundishauslaufes übereinstimmt, wird eine überaus kleinbauende Einrichtung geschaffen, bei welcher das Schleuderrad den Schmelzenfluß in Abhängigkeit von der Umdrehungsgeschwindigkeit entsprechend zerkleinert, wobei in den radial anschließenden Raum entsprechende Kühlmittel eingebaut sind. Die Einrichtung ist somit als im wesentlichen ringförmige Kammer aufgebaut, wodurch nur eine geringe Bauhöhe erforderlich ist und die Manipulation der Schmelzen entsprechend vereinfacht wird, da die Schmelze nicht mehr, wie bei konventionellen Dampfzerstäuberdüsen, entsprechend angehoben werden muß, um in einen darunterliegenden Raum ausgestossen zu werden. Die Verwendung eines derartigen Schleuderrades mit anschließender ringförmiger Kühlkammer stellt somit konstruktiv eine überaus kleinbauende Einrichtung dar, bei welcher dennoch wichtige Verfahrensparameter, welche für die Ausbildung geeigneter Teilchengrößen relevant sind, in weiten Grenzen und mit einfachen Mitteln eingestellt werden können. Bei Verwendung von Schleuderrädern wurde beispielsweise bei Schlackenschmelzen häufig beobachtet, daß diese zur Fadenbildung neigen, wodurch eine weitere Zerkleinerung nur mehr mit hohem Aufwand möglich wurde. Im Rahmen der erfindungsgemäßen Einrichtung ist es nun in einfacher Weise möglich die Temperatur der Schlacke während und unmittelbar nach der Zerkleinerung durch das Schleuderrad auf entsprechend hohen Temperaturen zu halten, um die Ausbildung von Tröpfchen sicherzustellen, wobei durch entsprechende Beheizung kleiner Abschnitte die gewünschten Temperaturen und damit die gewünschten Oberflächenspannungen zur Ausbildung der entsprechenden Tröpfchen in weiten Grenzen eingestellt werden können. Zu diesem Zweck ist mit Vorteil die erfindungsgemäße Ausbildung so getroffen, daß der Tundishauslauf mit dem Schleuderrad und dem Ringraum über ein beheizbares Anschlußrohr in Verbindung steht. Unmittelbar nach dem Tundishauslauf kann hiebei mit Brennern oder Heißgas und insbesondere bei Temperaturen von 1400° bis 1800° C noch eine Überhitzung der Schlacke vorgenommen werden, sodaß die Ausbildung feinster Tröpfchen durch das Schleuderrad gewährleistet ist. Das Schleuderrad selbst kann über einen entsprechend regelbaren Antrieb, beispielsweise im Drehzahlbereich von 3000 bis 20000 min-1, betrieben werden. Um die entsprechende Schlackenüberhitzung bis zum Auftreffen auf die entsprechenden Leitflächen des Schleuderrades auf kurzer Strecke zu erzielen, ist mit Vorteil die Ausbildung so getroffen, daß in das Anschlußrohr Brenner münden.The invention now aims to provide a device for atomizing melts, in which much smaller particle sizes can be achieved than with conventional granulation and in which the amount of gas generated in the process or required for the operation of the process can be kept low. To achieve this object, the inventive device of the type mentioned essentially consists in that the cooling space is designed as an annular space concentrically surrounding the centrifugal wheel and is connected to the centrifugal wheel with the interposition of a heatable annular chamber. Characterized in that, as is known per se, the melt, with the interposition of a conventional melt flow control element, such as a feeder or tundish stopper, reaches a centrifugal wheel whose axis of rotation essentially coincides with the axis of the tundish outlet, an extremely small-scale device is created, in which the centrifugal wheel comminutes the melt flow as a function of the speed of rotation, appropriate coolants being installed in the radially adjoining space. The device is thus constructed as an essentially annular chamber, which only requires a small overall height and the manipulation of the melts is correspondingly simplified, since the melt no longer has to be raised, as in conventional steam atomizing nozzles, in order to be ejected into an underlying space become. The use of such a centrifugal wheel with a subsequent annular cooling chamber thus constitutes an extremely small construction, in which nevertheless important process parameters, which are relevant for the formation of suitable particle sizes, can be set within wide limits and with simple means. When using centrifugal wheels, it was frequently observed, for example, that slag melts tend to form threads, which means that further comminution is only possible with great effort. In the context of the device according to the invention it is now possible in a simple manner to keep the temperature of the slag during and immediately after the comminution by the centrifugal wheel at correspondingly high temperatures in order to ensure the formation of droplets, with the desired temperatures and thus being heated by appropriate heating of small sections the desired surface tensions for forming the corresponding droplets can be set within wide limits. For this purpose, the design according to the invention is advantageously made such that the tundish outlet is connected to the centrifugal wheel and the annular space via a heatable connecting pipe. Immediately after the tundish has run out, the slag can still be overheated with burners or hot gas and in particular at temperatures from 1400 ° to 1800 ° C., so that the formation of very fine droplets is ensured by the centrifugal wheel. The impeller itself can have a corresponding controllable drive, for example, in the speed range from 3,000 to 20,000 min -1, to be operated. In order to achieve the appropriate slag overheating over a short distance until it strikes the corresponding guide surfaces of the centrifugal wheel, the design is advantageously made such that burners open into the connecting pipe.
Auch nach dem Verlassen des Schleuderrades ist es für die Ausbildung entsprechend feiner Tröpfchen und das Verhindern von Fadenbildung notwendig sicherzustellen, daß die Schlackenbzw. Schmelzetröpfchen eine entsprechend hohe Temperatur aufweisen, sodaß bedingt durch die Oberflächenspannung eine Tröpfchenausbildung begünstigt wird. Um auch nach dem Verlassen eine entsprechende Temperaturführung noch zu gewährleisten, ist die Ausbildung erfindungsgemäß so getroffen, daß der als Kühlraum ausgebildete Ringraum unter Zwischenschaltung einer beheizbaren Ringkammer an das Schleuderrad angeschlossen ist.Even after leaving the centrifugal wheel it is for training accordingly fine droplets and preventing Thread formation necessary to ensure that the slags or Melt droplets have a correspondingly high temperature, so that due to the surface tension Droplet formation is favored. To even after leaving to ensure appropriate temperature control, the training according to the invention is such that the annular space designed as a cooling space with interposition a heated ring chamber connected to the centrifugal wheel is.
Die als Ringkammer ausgebildete Kühlkammer kann in konventioneller Weise gekühlt werden und es kann die Ausbildung insbesondere zu diesem Zwecke so getroffen sein, daß die sich radial erstreckenden Wände des Kühlraumes doppelwandig als Strahlungskühlflächen ausgebildet sind, an deren Hohlraum Leitungen für Kühlmedium angeschlossen sind. Die Baumaße einer derartigen Kühlkammer lassen sich aber auch noch dadurch weiter verringern, wenn in die Kühlkammer unmittelbar Medien eingedüst werden, welche sich beispielsweise unter hohem Enthalpieverbrauch zersetzen. Mit Vorteil ist die Ausbildung daher so getroffen, daß der als Kühlraum ausgebildete Ringraum Anschlüsse für das Eindüsen von Kühlmitteln, wie z.B. Kohlenwasserstoffen, in den Ringraum aufweist.The cooling chamber designed as an annular chamber can be conventional Way cooled and it can be training in particular be made for this purpose so that the radially extending walls of the cold room double-walled as Radiation cooling surfaces are formed on the cavity Lines for cooling medium are connected. The dimensions of one Such a cooling chamber can also be used further decrease if media enters the cooling chamber immediately are injected, which are, for example, under high Decompose enthalpy consumption. Training is an advantage therefore taken so that the annular space designed as a cooling space Connections for the injection of coolants, e.g. hydrocarbons, has in the annulus.
Die Erfindung wird anhand eines in der Zeichnung schematisch dargestellten Ausführungsbeispieles einer erfindungsgemäßen Einrichtung teilweise im Schnitt näher erläutert.The invention is illustrated schematically in the drawing illustrated embodiment of an inventive The facility is partly explained in section.
In der Zeichnung ist mit 1 ein Schmelzentundish bezeichnet, dessen Schmelzeausflußregelorgan 2 als Feeder ausgebildet ist und durch Anheben in Richtung des Doppelpfeiles 3 eine entsprechende Regulierung des jeweils ausströmenden Schmelzestrahles 4 ermöglicht.In the drawing, 1 denotes a melt tundish, whose melt outflow regulator 2 is designed as a feeder and by lifting in the direction of the double arrow 3 a corresponding one Regulation of the melt stream flowing out 4 enables.
Druckdicht an diesen Tundish 1 ist ein Verbindungsrohr 5 angeschlossen,
in welchen über Ringdüsen 6 und 7 Heißgas eingeblasen
wird. Alternativ oder zusätzlich können jeweils Brenner
in den durch das Übergangsrohr 5 ausgebildeten Schacht münden,
sodaß der Schlackestrahl 4 entsprechend auf Temperaturen bis
zu 1800° C überhitzt werden kann. An dieses Verbindungsrohr 5
ist eine Ringkammer 8 angeschlossen, welche aus mehreren Abschnitten
besteht. Im ersten Abschnitt dieser Ringkammer 8 ist
ein Schleuderrad 9 rotierbar gelagert, wobei die Rotationsachse
10 im wesentlichen mit der Achse 11 des Tundishauslaufes
fluchtet. Die Schmelze bzw. Schlacke trifft somit auf das
rotierende Schleuderrad 9 auf und wird in radialer Richtung in
der Ringkammer 8 auswärts geschleudert. In einem ersten an das
Schleuderrad anschließenden Abschnitt der Ringkammer, welcher
mit 12 bezeichnet ist, erfolgt eine weitere Erhitzung, um die
Schmelzentemperatur entsprechend den gewünschten Parametern
beispielsweise wiederum auf Temperaturen zwischen 1400° und
1800° C zu halten, sodaß eine feine Tröpfchenbildung unter
Vermeidung einer Fadenbildung erfolgt. Der äußere Bereich der
Ringkammer 8 ist als ringförmige Kühlkammer 13 ausgebildet,
dessen Wände doppelwandig ausgebildet sind. In den zwischen
den Wänden eingeschlossenen Hohlraum 14 kann entsprechendes
Kühlmittel eingeleitet werden. Zusätzlich sind Düsen 15 vorgesehen,
über welche beispielsweise Kohlenwasserstoffe eingedüst
werden, welche unter stark endothermer Zersetzung den feinen
Schmelzetröpfchen rasch Wärme entziehen und auf diese Weise
eine sichere Erstarrung und Abkühlung gewährleisten.A
Das gebildete Mikrogranulat verläßt die ringförmige Kühlkammer am Umfang derselben insbesondere mit Temperaturen zwischen 200° und 500° C und kann außerhalb der Ringkammer gesammelt werden.The microgranules formed leave the annular cooling chamber on the circumference of the same, in particular with temperatures between 200 ° and 500 ° C and can be collected outside the annulus become.
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT02450031T ATE339879T1 (en) | 2001-02-27 | 2002-02-13 | DEVICE FOR ATOMIZING AND GRANULATING MELTS |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT3082001 | 2001-02-27 | ||
| AT0030801A AT410097B (en) | 2001-02-27 | 2001-02-27 | DEVICE FOR SPRAYING AND GRANULATING MELTS |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP1234889A1 true EP1234889A1 (en) | 2002-08-28 |
| EP1234889B1 EP1234889B1 (en) | 2003-12-10 |
Family
ID=3671281
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP02450031A Expired - Lifetime EP1234889B1 (en) | 2001-02-27 | 2002-02-13 | Apparatus for granulating of liquid slag |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP1234889B1 (en) |
| AT (2) | AT410097B (en) |
| DE (1) | DE50200129D1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT411689B (en) * | 2002-09-10 | 2004-04-26 | Tribovent Verfahrensentwicklg | Pulverizing and granulating melts, especially liquid slag, comprises expelling the molten stream as a jacket stream with a hot gas from a tundish so that the stream hits different sites on the spinner gate |
| EP1400602A3 (en) * | 2002-09-10 | 2004-07-21 | Tribovent Verfahrensentwicklung GmbH | Method and apparatus for the granulation of liquid melts |
| GB2508199A (en) * | 2012-11-23 | 2014-05-28 | Siemens Vai Metals Tech Gmbh | Slag granulation device with a tundish and a slag flow control means |
| CN117126970A (en) * | 2023-08-29 | 2023-11-28 | 一重集团大连工程技术有限公司 | A centrifugal granulation waste heat recovery device |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10340880A1 (en) * | 2003-09-04 | 2005-03-31 | Polysius Ag | Process for pulverizing slag from a blast furnace used during pig iron manufacture comprises adding an additional material to the slag after removing pig iron and before pulverizing |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2333218A (en) * | 1938-11-11 | 1943-11-02 | Pazsiczky Gedeon Von | Method of and apparatus for producing glass fibers |
| JPS52123992A (en) * | 1976-04-12 | 1977-10-18 | Kawasaki Heavy Ind Ltd | Method and apparatus for cooling slag |
| JPS5443896A (en) * | 1977-09-14 | 1979-04-06 | Kubota Ltd | Granulating device for scum |
| EP1038976A1 (en) * | 1999-03-24 | 2000-09-27 | Holderbank Financiere Glarus Ag | Method of granulating and pulverizing slag or metal melts |
-
2001
- 2001-02-27 AT AT0030801A patent/AT410097B/en not_active IP Right Cessation
-
2002
- 2002-02-13 DE DE50200129T patent/DE50200129D1/en not_active Expired - Fee Related
- 2002-02-13 EP EP02450031A patent/EP1234889B1/en not_active Expired - Lifetime
- 2002-02-13 AT AT02450031T patent/ATE339879T1/en not_active IP Right Cessation
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2333218A (en) * | 1938-11-11 | 1943-11-02 | Pazsiczky Gedeon Von | Method of and apparatus for producing glass fibers |
| JPS52123992A (en) * | 1976-04-12 | 1977-10-18 | Kawasaki Heavy Ind Ltd | Method and apparatus for cooling slag |
| JPS5443896A (en) * | 1977-09-14 | 1979-04-06 | Kubota Ltd | Granulating device for scum |
| EP1038976A1 (en) * | 1999-03-24 | 2000-09-27 | Holderbank Financiere Glarus Ag | Method of granulating and pulverizing slag or metal melts |
Non-Patent Citations (2)
| Title |
|---|
| DATABASE WPI Section Ch Week 197748, Derwent World Patents Index; Class L02, AN 1977-85315Y, XP002202226 * |
| PATENT ABSTRACTS OF JAPAN vol. 003, no. 068 (C - 048) 13 June 1979 (1979-06-13) * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT411689B (en) * | 2002-09-10 | 2004-04-26 | Tribovent Verfahrensentwicklg | Pulverizing and granulating melts, especially liquid slag, comprises expelling the molten stream as a jacket stream with a hot gas from a tundish so that the stream hits different sites on the spinner gate |
| EP1400602A3 (en) * | 2002-09-10 | 2004-07-21 | Tribovent Verfahrensentwicklung GmbH | Method and apparatus for the granulation of liquid melts |
| GB2508199A (en) * | 2012-11-23 | 2014-05-28 | Siemens Vai Metals Tech Gmbh | Slag granulation device with a tundish and a slag flow control means |
| CN117126970A (en) * | 2023-08-29 | 2023-11-28 | 一重集团大连工程技术有限公司 | A centrifugal granulation waste heat recovery device |
Also Published As
| Publication number | Publication date |
|---|---|
| DE50200129D1 (en) | 2004-01-22 |
| ATA3082001A (en) | 2002-06-15 |
| AT410097B (en) | 2003-01-27 |
| ATE339879T1 (en) | 2003-12-15 |
| EP1234889B1 (en) | 2003-12-10 |
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