DE102023206241A1 - Method and strand guiding device for operating a cooling chamber - Google Patents

Abstract

The invention relates to a method for operating a cooling chamber in a strand guide device and the strand guide device 10 as such. The strand guide device is used to deflect a freshly cast casting strand, typically made of metal, horizontally. During the deflection, the casting strand passes through a cooling chamber 1 within the strand guide device 2, in which it is sprayed with a coolant 33 to form steam 5. The steam, at least with sucked in false air, forms a steam-air mixture 5', which is sucked out of the cooling chamber with the help of a suction device 20. In particular, in order to reduce the pollutant content of the sucked-in and extracted steam-air mixture 5' and its emission into the environment, the present invention provides for pollutants contained in the steam-air mixture 5' to be removed using a separator 6, 6` to deplete.

Description

The invention relates to a method for operating a cooling chamber in a strand guide device of a continuous casting plant for casting a casting strand, in particular made of metal. In addition, the invention relates to the strand guide device having a cooling device with the cooling chamber.

Such continuous casting systems are basically known in the prior art, e.g. B. from the German disclosure document DE 10 2017 209 731 A1 . 5 shows the continuous casting system 100 disclosed there, in which a metal casting strand 13, for example, is cast with the aid of a mold 40 and is subsequently deflected horizontally with the aid of a strand guide device 10. It is also known that the casting strand that has not yet solidified, for example made of steel, has a plurality of cooling chambers 1, 1' within the strand guide device 6 passes through, in which the casting strand 13 is cooled by spraying with a coolant 33 to form steam 5. The steam is at least partially saturated with the coolant and is typically sucked out of the respective cooling chamber 1, 1' laterally, ie transversely to the pouring direction, with the aid of a suction device 20 individually assigned to each cooling chamber. For this purpose, the suction device 20 has an induced draft fan 8, a suction opening 3 in a side wall of the cooling chamber 1, 1 'and a suction channel 7 connecting the suction opening and the induced draft fan 8.

Depending on the quality of the cast steel and the width and thickness of the casting strand, different cooling strategies are used, i.e. different amounts of water are applied to the casting strand at different positions within the continuous casting system. The amount of water applied locally depends on the desired cooling effect, on the speed of the casting strand within the strand guide device, on the cooling water temperature and/or on the temperature of the casting strand. It happens again and again that very little or even no water is applied to the lower areas of the strand guide, i.e. there is practically no cooling there. In these cases, the suction devices only suck in dry air from the cooling chambers there. Pre-cleaning of a steam-air mixture in the respective cooling chamber is not possible in this way.

The German disclosure document DE 10 2015 209 399 A1 discloses a device for removing exhaust air from the environment of a metal strand using a suction device. The suction device is arranged on one side of the conveying section of the casting strand. Opposite the suction device on the other side of the conveyor path, a fan is arranged to generate an air flow to convey the exhaust air in a blowing direction transverse to the conveyor path, as far as possible into the suction device. A control device is used to adjust the delivery rate of the blower and the suction device depending on a measured speed of the metal strip. By arranging the blower opposite the suction device, the air particles of the exhaust air can be sucked out with significantly less air volume flow and therefore with significantly less energy expenditure than if the air volume flow had to be sucked in through the suction device alone. The suction device is followed by an exhaust air treatment system for cleaning the exhaust air sucked in by the suction device, in particular for filtering out airborne substances from the exhaust air.

Furthermore, the German patent specification discloses DE 10 2006 045 791 B4 a method and an arrangement for reducing pollutant emissions in the exhaust air of a rolling mill. The method provides a condensation step in which part of the exhaust air passes from the gas phase to the liquid phase with the formation of droplets, and a particle separation step in which the droplets formed in the condensation step are separated. The condensation step takes place in a condenser, which is designed as a heat exchanger. With the help of an exhaust air return line, parts of the exhaust air flow can be returned to the rolling mill. Pre-cooled outside air can be supplied to the heat exchanger to promote the condensation step. The process is primarily intended to be used in a cold rolling mill.

The invention is based on the object of developing a known method for operating a cooling chamber in a strand guiding device and the known strand guiding device itself in such a way that emission-relevant substances are removed from the steam-air mixture (5`). Substances that are particularly relevant to emissions are those that are harmful to people and the environment, but also to machines, and limit values are often set for their proportions in the air.

This task is achieved with regard to the claimed method by the method according to claim 1. Accordingly, the method is characterized in that the steam-air mixture is depleted using at least one separator, in particular by condensation.

When a freshly cast casting strand made of metal, especially steel, passes through the strand guide device, it is still very hot on the surface, typically around 1100°C to 900°C. By spraying the casting strand with a coolant, a vapor-air mixture is formed in the cooling chamber, which is at least partially saturated with the coolant that evaporates immediately. So that this steam-air mixture cannot endanger people and equipment (machines) on the casting platform (work platform) arranged above the cooling chamber and within the strand guide, the steam-air mixture, which consists of a mixture of steam and sucked in false air , sucked out of the cooling chamber by means of an induced draft fan and guided over the continuation of the suction channel and thus discharged from the cooling chamber. According to the invention, the steam-air mixture is passed through at least one separator, which depletes the steam-air mixture in terms of its dirt and pollutant load, for example through condensation. As part of its function as a condenser, the separator is designed to cool the steam-air mixture, preferably adiabatically, and at the same time to remove moisture from it. According to the invention, this is done in that the moisture is condensed out of the sucked-in steam-air mixture using the separator. By reducing the humidity in the entire exhaust system, corrosion and, if necessary, erosion of the pipes and the exhaust fan are reduced. This in turn reduces the maintenance effort for companies.

In other words: As part of the “condensation” functionality, the separator is also designed to significantly reduce the pollutant load in the vapor-air mixture. Pollutants such as “dust”, “fine dust” and “VOC (highly volatile organic substances)” accumulate on the condensed particles in the air during condensation and are removed together with them via a sewer and sent to appropriate post-treatment.

If the separator is reduced to the “condensing” functionality described, it is also referred to as a capacitor for simplicity.

Alternatively or in addition to its “condensation” functionality, the separator preferably also has further functionalities for depleting pollutants in the vapor-air mixture. The separator can be designed to implement only one, several or all of its functionalities described below in succession or simultaneously.

The terms “depletion” and “(pre-)conditioning” of the steam-air mixture are used interchangeably.

Preferably, this depletion of pollutants succeeds so well that specified emission limit values can be safely adhered to.

The false air is extracted from the hall surrounding the strand guide device and is usually very heavily contaminated or contaminated, in particular with substances that are harmful to health.

According to a first exemplary embodiment, the separator is arranged in front of the suction opening of the suction device in the cooling chamber. This has the advantage that the condensate resulting from the condensation, in particular condensed coolant, can be drained away through a wastewater channel (sintering channel) within the cooling chamber. This channel is always there anyway; Therefore, advantageously no additional drainage channel needs to be provided.

Alternatively, according to a second embodiment, the separator can also be installed in the suction channel of the suction device, which connects the suction opening and an induced draft fan of the suction device to one another. With this arrangement of the separator, however, the condensate must be removed in the suction channel.

The same problem arises for a further separator, which would optionally be installed in the suction channel in addition to the separator in front of the suction opening according to a third exemplary embodiment. The “additional separator” is basically designed to implement the same functionalities as the separator.

According to a fourth exemplary embodiment, the steam-air mixture can be additionally depleted by means of attachments and installations in front of, on or in the induced draft fan of the suction device. The attachments and fixtures refer to installations, e.g. in the form of spray nozzles and/or specially positioned impeller blades of the induced draft fan, which lead to a reduction in emissions. With medium (mainly water) introduced via the spray nozzles and specially positioned impeller blades, the suction-draft blower also functions as a centrifugal separator for the pollutants in question.

The separator, the additional separator and/or the attachments and installations precondition the steam-air mixture extracted from the cooling chamber before it passes through the suction-draft fan This is either released into the environment via a chimney (not favored according to the invention) or returned to the cooling chamber. Ie: The reduction of the pollutant load in the steam-air mixture according to the first to fourth exemplary embodiments is also referred to as preconditioning.

According to a fifth advantageous exemplary embodiment, the method according to the invention provides that additional air is blown into the cooling chamber using a pressure blower. In this way, the efficiency of the suction device is significantly increased, because significantly less suction power is now required because large quantities of the sucked in steam-air mixture are fed to the suction opening through the compressed air blower, especially if the compressed air blower is arranged opposite the suction opening of the suction device. The additional air supplied is therefore part of the steam-air mixture alongside the steam and the sucked-in false air. The additional air supplied can either be fresh air drawn in from outside the hall in which the strand guide device is operated (1st variant) and/or air extracted from the hall (2nd variant). In the two variants, a more or less complex conditioning of the sucked in air may be required before it is fed or returned to the cooling chamber, depending in particular on its respective preload with pollutants.

• Durch regionale oder jahreszeitabhängige Wetterunterschiede verändert sich die Kondensatbildung in der Kühlkammer. Hierbei ist das Ansaugen der sogenannten Falschluft durch nicht vermeidbare Ein- und Auslass-Öffnungen in der Kühlkammer zusätzlich zu der kontrolliert zugeführten zusätzlichen Luft ein wesentliches Problem. Anders als die variable einstellbare zusätzliche Luft, wird die Falschluft konstruktionsbedingt immer mit angesaugt. Die unfreiwillig mit angesaugte Falschluft wird als höher schadstoffbelastet (vornehmlich Staub) eingestuft als die zusätzliche Luft. Die Falschluft ist immer Bestandteil des Dampf-Luft-Gemisches in der Kühlkammer. Vorteilhaft wäre eine möglichst konstante mittlere Kühlkammerzieltemperatur im Bereich von vorzugsweise 40°C bis 60°C und/oder eine relative Ziel-Luftfeuchte von über 80%. Über die beanspruchte gezielte Einströmung einer definierten Menge der zusätzlichen Luft mit einer entsprechend geeignet gewählten Temperatur kann die Zieltemperatur des entstehenden Dampf-Luft-Gemisches eingestellt werden. Gleichermaßen kann durch die geeignete Einstellung der Feuchte der zusätzlichen Luft die gewünschte relative Ziel-Luftfeuchte bei dem entstehenden Dampf-Luft-Gemisch in der Kühlkammer eingestellt werden.

A first possibility for conditioning the supplied air, in particular the fresh air sucked in, is to change or adjust its temperature and/or its humidity in such a way that when it is mixed with the steam-air mixture already in the cooling chamber, the resulting mixture a desired target temperature and/or a desired target humidity is set. To the background:

• Regional or seasonal weather differences change the formation of condensation in the cooling chamber. A major problem here is the suction of so-called false air through unavoidable inlet and outlet openings in the cooling chamber in addition to the additional air supplied in a controlled manner. Unlike the variable, adjustable additional air, the false air is always sucked in due to the design. The false air that is involuntarily sucked in is classified as containing more pollutants (mainly dust) than the additional air. The false air is always part of the steam-air mixture in the cooling chamber. It would be advantageous to have a mean cooling chamber target temperature that is as constant as possible in the range of preferably 40 ° C to 60 ° C and / or a relative target air humidity of over 80%. The target temperature of the resulting steam-air mixture can be set via the targeted inflow of a defined amount of additional air with a correspondingly selected temperature. Likewise, by appropriately adjusting the humidity of the additional air, the desired relative target air humidity can be set for the resulting steam-air mixture in the cooling chamber.

By supplying the additional air, which is cleaner compared to the steam-air mixture in the cooling chamber, the proportion of undesirable foreign substances per unit volume of the resulting steam-air mixture in the cooling chamber can advantageously be reduced. End of background information.

• In der Kühlkammer wird der Dampf im Wesentlichen dadurch erzeugt, dass das Kühlmittel, hauptsächlich Wasser, beim Aufbringen auf den noch heißen Gießstrang verdampft. Neben dem Kühlmittel können auch Rückstände von Gießpulver und Schmiermittel, z. B. Öle und Fette, welche für den Betrieb bestimmter Anlagenteile, z.B. für die Segmentrollen, benötigt werden, in das Dampf-Luft-Gemisch gelangen. Durch den Kontakt mit dem heißen Gießstrang und dem damit verbundenen Verdampfungsprozess, können sich Anteile der genannten Stoffe unerwünschter Weise in dem Dampf-Luft-Gemisch befinden. Durch die erfindungsgemäß vorgesehene Beimischung von Trennungsmitteln, sogenannten Adsorbentien, können diese Stoffe aus dem Dampf-Luft-Gemisch wieder gelöst werden und gegebenenfalls separat aufgefangen werden. Eine analoge Konditionierung kann auch für die aus der Halle abgesaugte zusätzlichen Luft durchgeführt werden.

The conditioning of the additional air in the form of the air returned from the cooling chamber (3rd variant) can be done by depleting it by adding separating agents to dissolve foreign substances from the steam-air mixture. To the background:

• In the cooling chamber, the steam is essentially generated by the coolant, mainly water, evaporating when it is applied to the still hot casting strand. In addition to the coolant, residues of casting powder and lubricants, e.g. B. oils and fats, which are required for the operation of certain system parts, for example for the segment rollers, get into the steam-air mixture. Due to contact with the hot casting strand and the associated evaporation process, portions of the substances mentioned can undesirably be found in the steam-air mixture. By adding separating agents, so-called adsorbents, as provided according to the invention, these substances can be dissolved again from the steam-air mixture and, if necessary, collected separately. Analogous conditioning can also be carried out for the additional air extracted from the hall.

End of background information.

The coolant that is used as part of said secondary cooling in the cooling chambers of the strand guide device to cool the casting strand typically consists of 100% water.

By providing the targeted blowing of the additional air 14 into the cooling chamber with the aid of a pressure fan, the dimensions of the entire suction device, ie the induced draft fan, the suction channel and the suction opening, can be smaller. This is therefore true because the compressed air blower supplies large quantities of the steam-air mixture to the suction opening, which would previously have to be sucked in by the suction device alone, ie without the presence of the pressure blower. Reducing the size of the suction device also has the advantage that the volume flow of the steam-air mixture at the outlet of the suction device and thus the necessary power consumption of the suction device is reduced in the present invention.

Reducing the dimensions of the suction device also has the advantage that installation space can be saved and that assembly is made easier in tight spaces. The reduced volume flow in the cooling chamber and the suction device favors the installation of the separator in front of the suction opening because the separator is more effective at low air speeds, i.e. H. can be operated with lower energy consumption. Furthermore, the reduced volume flow from the cooling chamber advantageously also means that less false air is sucked in.

According to a sixth exemplary embodiment, part of the extracted and pre-condensed steam-air mixture at the outlet of the suction device can advantageously be fed back to the cooling chamber via a first partial air return line, keyword endless filtration. The remaining steam-air mixture, which is released into the environment via leaks in pipes and ducts and/or ultimately via the chimney (not favored by the present invention), is reduced accordingly.

The measures described so far for depletion or purification of the steam-air mixture, i.e. the various options for preconditioning and the supply of additional air according to the 1st or 2nd variant described above, are often not sufficient to meet new, even stricter limit values for emissions into the ambient air into the ambient air.

Therefore, according to a seventh exemplary embodiment for the cooling chamber, the invention provides that the steam-air mixture extracted from the cooling chamber is not discharged to the environment via the continued exhaust air duct via the chimney, but with a variably adjustable first partial quantity via the first partial air return line returned to the cooling chamber and fed to a conditioning device with a variably adjustable second portion. In the conditioning device, the steam-air mixture is conditioned or prepared for reuse within the strand guide device, in particular in its cooling chamber, i.e., above all, it is further cleaned of pollutants. The processing takes place in particular by cooling, dehumidifying and/or cleaning the incoming preconditioned steam-air mixture. The processing advantageously goes to such an extent that the conditioned steam-air mixture at the outlet of the conditioning device satisfies even the latest strict limit values for air pollution control. The steam-air mixture conditioned in this way is intended and suitable for being largely or completely fed back into the strand guiding device, in particular its cooling chamber, as additional air (3rd variant), so that an almost closed air circuit is created, or into the hall surrounding the strand guiding device to be delivered. The operation of the strand guide device can thus advantageously be realized at least without any environmentally harmful emissions via the chimney into the ambient air.

Since moist exhaust air no longer needs to be fed into the outside air via the chimney, water no longer needs to be replaced, which results in significant water savings in the corresponding cooling circuits of the secondary cooling. Furthermore, all emissions are eliminated so that no more harmful emissions are generated by the strand guide device.

The partial air quantities are adjusted using distribution devices, e.g. distribution flaps. The proportions of the individual partial air quantities can be between 0% and 100%, with the sum of the individual partial air quantities set per distribution device being 100%.

The above-mentioned task is further solved by a strand guide device according to claim 11. The advantages of this solution correspond to the advantages mentioned above with regard to the claimed method.

Further advantageous embodiments of the method according to the invention and the claimed strand guide device are the subject of the dependent claims.

• 1 die erfindungsgemäße Kühlkammer mit zugeordneter Absaugeinrichtung gemäß einem ersten bis sechsten Ausführungsbeispiel;
• 2 verschiedene Ausführungen des Abscheiders;
• 3 die Kühlkammer gemäß einem siebten Ausführungsbeispiel mit einer Konditionierungseinrichtung;
• 4 eine Strangführungseinrichtung mit zwei hintereinander angeordneten Kühlkammern gemäß einem achten Ausführungsbeispiel der Erfindung;
• 5 eine Strangführungseinrichtung gemäß dem Stand der Technik; und
• 6 eine Kühlkammer mit zugeordneter Absaugeinrichtung gemäß dem Stand der Technik

zeigt.Six figures are attached to the description, where:

• 1 the cooling chamber according to the invention with associated suction device according to a first to sixth exemplary embodiment;
• 2 different versions of the separator;
• 3 the cooling chamber according to a seventh embodiment with a conditioning device;
• 4 a strand guide device with two cooling chambers arranged one behind the other according to an eighth embodiment of the invention;
• 5 a strand guide device according to the prior art; and
• 6 a cooling chamber with an associated suction device according to the prior art

shows.

The invention is described below with reference to 1 until 4 described in detail in the form of exemplary embodiments. In all figures, the same technical elements are designated with the same reference numerals.

1 essentially shows a cross section through a cooling chamber 1 of a strand guide device 10 of a continuous casting plant, as introduced above with reference to 5 and 6 was described as prior art. In 1 In particular, a segment 12 of the strand guide device 10 with strand guide rollers 2 is shown in cross section, between which the casting strand 13 is guided. The cooling chamber 1 forms an enclosure for the strand guide device 1, in particular the segments 12. It has undesirable openings through which false air 15 in the form of ambient air or hall air is inevitably sucked in. 1 shows the cooling chamber 1 with a plurality of exemplary embodiments according to the invention, as described below

On its way through the strand guide device, more precisely through its segments 12, the casting strand 13 is cooled in the cooling chamber 1 by spraying with a coolant 33. The steam 5 created by the evaporation of the coolant, together with the inevitably sucked in false air 15, forms a steam-air mixture 5`. This is at least partially saturated with the coolant 33.

Can be seen in 1 furthermore, that the cooling chamber 1 is assigned a suction device 20 for sucking out the steam-air mixture 5' from the cooling chamber 1. The suction device 20 comprises an induced draft fan 8 and a suction duct 7, which has a suction opening 3 in the cooling chamber 1 with the induced draft fan 8 connects. The continuation of the suction channel 7 downstream of the induced draft fan 8 is designated by the reference number 9. The continuation of the suction channel can direct the extracted steam-air mixture 5' to a chimney 19. However, this variant is not favored according to the invention.

In contrast to the prior art, according to the invention at least one (numeral) preferably multi-layer separator 6, 6' is provided, as in 2 , left and right illustration, shown as an example with 2 and 3 layers, also called packages. The separator 6 and possibly a further separator 6 'are designed to implement at least one (number word) of the following functions and to treat the steam-air mixture 5' accordingly:

o Condensation

Condensation describes the functionality with which the aerosols, fine dust aerosols and water vapor contained in the exhaust air, i.e. in the extracted steam-air mixture 5', are separated from the steam-air mixture 5' by active cooling (with cooling water). This can be referred to as physical deposition. As part of the condensation function, the steam-air mixture is preferably cooled adiabatically and at the same time moisture is removed. According to the invention, this is done in that the moisture is removed from the sucked-in and sucked-out steam-air mixture 5 using the separator 6, 6' ` is condensed out.

◯ Droplet separation

This function of the separator is realized by the sucked-in steam-air mixture 5` being diverted at a minimum speed. Due to their mass inertia, any heavy drops present in the mixture 5' cannot follow the deflection of the air. Instead, they take a trajectory that deviates from the deflection. This effect can be exploited in order to enable a first separation of the coarse drops with attached dirt and/or pollutants from the mixture 5'. The function can be described as mechanical separation.

◯ Air rectification

The rectification of the sucked-in steam-air mixture 5` within the separator can be achieved by the special arrangement of the separator packages 2 and their distance from each other can be optimally adjusted. Uniform flow velocities are created over the entire suction surface without significantly changing the penetration depth. In this way, the effective suction area can even be expanded beyond the size of the actual opening of the suction point. Tests have shown that the suction area can be increased by up to 30%.

◯ Self-cleaning

The self-cleaning functionality of the separator is implemented in such a way that drops of dirt and/or pollutant particles attached to the smooth pipes of the separator are safely removed with draining condensate water. The permanently moist pipes virtually eliminate the risk of caking. This is also shown by experience with tube coolers in related applications.

Individual or all of the mentioned functionalities can take place sequentially or simultaneously. If the separator 6 and/or the further separator 6' is designed to implement two or more of the functions mentioned, they are also referred to as multifunctional separators.

The separator 6 is, as in 1 shown, according to a first exemplary embodiment, advantageously arranged in front of the suction opening 3 of the suction device 20 in the cooling chamber. This is advantageous because the condensate 22 formed in the separator 6, in particular the condensed coolant, can then be removed through a sewer 24 or a sinter channel within the cooling chamber 1. Alternatively, according to a second exemplary embodiment, the separator can also be arranged in the flow direction of the steam-air mixture 5' between the suction opening 3 and the induced draft fan 8 in the suction duct 7 or in the exhaust air duct 9 which continues behind the induced draft fan in the flow direction.

If, according to a third exemplary embodiment, not only a single separator 6 but also a further separator 6' is provided, this can (also) be arranged in the suction channel 7. In cases where the separator 6 and/or the further separator 6' are arranged in the suction channel 7, there must be a possibility in the suction channel 7 for collecting and discharging the condensate 22 generated there.

The cooling water required for the operation of the separator can be taken from the secondary cooling water of the strand guide device 10 and does not need to be specially conditioned. In addition, the water that is separated via the separator 6, 6` is returned to the cooling circuit and is not supplied to the environment as a steam-air mixture via the chimney 19. This leads to additional water savings.

Optionally, the depletion of the steam-air mixture 5' - except through the separator 6, 6' - according to a fourth exemplary embodiment can also be done by means of attachments and internals 16, for example spray nozzles, which are in front of, in, on or - in the direction of flow - behind the induced draft fan 8 are arranged. They offer an additional possibility of reducing the pollutant content of the steam-air mixture 5 'before it is passed on into the exhaust chimney 19, into a first partial air return line 11 or into a conditioning device Z, see 3 , reduce or precondition.

According to a fifth exemplary embodiment, additional air can optionally be blown into the cooling chamber 1 using a pressure blower 4, the pressure blower 4 preferably, as in 1 shown, is arranged opposite the suction opening 3 of the suction device 20 in the cooling chamber 1. The additionally supplied air 14 mixes in the cooling chamber 1 with the steam-air mixture 5 'already there.

The additional air 14 can be generated by conditioning the steam-air mixture 5' extracted from the cooling chamber 1 with the conditioning device Z, by conditioning hall air 80 extracted from the hall 200 with a further conditioning device 60 and / or by preferably conditioning fresh air 70, also with the conditioning device 60, with the fresh air being sucked in from outside the hall 200.

The type and extent of conditioning depend on the type and quality of the air sucked in. The proportions of the three possible components mentioned in the additional air 14 are adjusted via a third distribution device Z7_3 and/or a fourth distribution device Z7_4, each designed, for example, in the form of a distributor flap. With the help of the distribution device Z7_4, for example, the proportions of the sucked-in hall air 80 and the sucked-in fresh air 70 in the additional air 14 can be variably preset. These proportions are depleted to the extent necessary with the help of the further conditioning device 60. With the help of the distribution device Z7_3, for example, the proportions of the conditioned steam-air mixture 5" and the air at the outlet of the further conditioning device Z7_4 in the additional air 14 can be variably adjusted. The individual proportions of the three possible components in the total amount of additional air 14 supplied is between 0% and 100%, and in total it is always 100%. The in 1 The arrangement of the distribution devices Z7_3 and Z7_4 as well as the further conditioning device 60 shown are merely examples. Other interconnections of these devices or only parts of the devices are also conceivable, depending on which of the possible components th or proportions that additional air 14 should contain at all. The distribution devices Z7_3 and Z7_4 as well as the further conditioning device 60 can also be completely omitted if only the conditioned steam-air mixture 5" is to be supplied into the cooling chamber 1 as additional air 14 or no additional air 14 at all.

In front of or in the separator 6 or in the suction channel 7, collecting grilles can be provided as system protection in order to protect subsequent system parts in the flow direction from unwanted external influences caused by coarse foreign parts sucked in.

According to a sixth exemplary embodiment, a first distribution device Z7_1, for example in the form of a first distribution flap, is located in the continued exhaust air duct 9, preferably at the outlet of the induced draft fan 8, in front of the first partial air return line 11. The first distribution device Z7_1 is used to variably divide the preconditioned steam-air mixture 5` into a first and a second subset. The first portion of the preconditioned steam-air mixture is fed back into the cooling chamber 1 via the first partial air return line 11.

The second portion of the steam-air mixture is passed past the first partial air return line 11 and is either discharged via the chimney 19 into the environment of the strand guide device 100 (not favored by the invention) or, according to a seventh exemplary embodiment, via the continued exhaust air duct 9 Conditioning device Z supplied.

3 shows the cooling chamber 1 according to the invention according to the seventh exemplary embodiment. This essentially concerns the treatment of the steam-air mixture 5' which has been sucked out of the cooling chamber 1 and - as described above - preferably already preconditioned.

In the conditioning device Z, the second portion of the steam-air mixture preferably first passes through a cooler Z2 for cooling purposes.

By cooling, the steam-air mixture 5` is further preconditioned for subsequent removal of (air) moisture. A dehumidifier Z3 is connected downstream of the cooler Z2 for dehumidifying the cooled steam-air mixture by (out) condensing. The dehumidifier is followed by a filter Z4 for cleaning the steam-air mixture and a heat exchanger Z1 for reheating the dehumidified and cooled steam-air mixture, preferably by removing heat from the supplied second portion of the extracted steam-air mixture at the inlet Conditioning device Z. As a result, the incoming steam-air mixture is advantageously pre-cooled before it reaches the cooler Z2. The conditioning device Z finally outputs a conditioned steam-air mixture 5". The conditioning device Z does not necessarily have to have all of the components mentioned, such as the cooler Z2, the dehumidifier Z3, the filter Z4 and the heat exchanger Z1. Depending on the design, it can the conditioning device Z also only contains individual components.

The steam-air mixture 5" conditioned in this way is passed to a second distribution device Z7_2. This second distribution device, for example designed in the form of a second distribution flap, serves to variably divide the conditioned steam-air mixture 5" into a first and a second subset. The first subset is fed back into the cooling chamber 1 via a second partial air return line 17 as the additionally supplied air 14 or a portion thereof. Optionally, this is done with the addition of hall air 80 or fresh air 70, as described above with reference to 1 already described and as described in 3 third distribution device Z7_3 indicated by dashed lines. The second subset of the conditioned steam-air mixture 5" is led via an output line 18 into the hall 200 surrounding the strand guide device 10 or outside the hall 200.

Preferably, the second distribution device Z7_2 is followed by a damper Z6 for dampening the flow noise of the second subset of the conditioned steam-air mixture 5" in the output line 18.

4 illustrates an eighth embodiment of the invention. Accordingly, in the strand guide device according to the invention, a plurality of cooling chambers 1, 1 'are arranged one behind the other, through which the casting strand 13 cast in the mold 40 passes through one after the other. According to the invention, two adjacent cooling chambers 1, 1' are each connected to one another via an (exhaust) air duct 50, which extends in the casting direction G, and thus form an overall system that communicates with one another in terms of air technology. Only the first cooling chamber 1, ie the cooling chamber immediately downstream of the mold 40, is connected to a lateral suction device 20. Unlike in the prior art, the downstream cooling chambers 1' in the casting direction G no longer each have their own lateral suction device, but instead the exhaust air, ie the steam-air mixture, is also drawn from the downstream cooling chambers 1' against the casting direction G through the Said air duct 50 into the first top cooling chamber 1, ultimately caused by the suction device 20 assigned to the first cooling chamber. According to the invention, the extracted exhaust air passes through an air washer 52 within the air channels 50 before it reaches the first uppermost cooling chamber 1 and is sucked off there by said suction device 20. By first passing through the air washer 52, the exhaust air from a cooling chamber is pre-cleaned before it reaches the first or uppermost cooling chamber.

The air washers 52 are operated with water. The water required for this can be taken from the secondary cooling water circuit, with which the casting strand 13 is cooled in the upper cooling chambers (secondary). This is possible because, as mentioned, a particularly large cooling capacity is no longer required, particularly in the cooling chambers arranged further down in the casting direction G; The (secondary) cooling water available there can therefore be used for the air washers there to clean the exhaust air.

The air channels 50 are virtually assigned to the cooling chambers 1'; In this respect, the exhaust air is cleaned with the help of the air washers 52, so to speak, within the downstream cooling chambers 1 '. The cooling water from the secondary cooling water circuit used to operate the air washer 52 does not need to be specially conditioned beforehand. After it has passed through the air washer 52, it can be fed back into the secondary cooling water circuit and it does not have to be separately processed for this purpose. This leads to additional water savings. Overall, the use of the air washer 52 brings about a significant pre-cleaning, i.e. reduction of the pollutant content in the exhaust air of the respective cooling chamber.

Reference symbol list

1

Cooling chamber

1'

Cooling chamber

2

Strand guide rollers

3

Intake opening

4

pressure blower

5

steam

5`

Steam-air mixture

5"

conditioned steam-air mixture

6

separator

6`

another separator

7

Suction channel

8th

induced draft fan

9

continued exhaust air duct (chimney)

10

Strand guide device

11

first partial air return line

12

Segment of the strand guide device

13

casting strand

14

additional air

15

with sucked in false air

16

Attachments and/or installations, in front of, on or in the induced draft fan

17

second partial air return line

18

Output line

19

Chimney

20

Suction device

22

condensate

24

sewer

30

Cooling device

33

coolant

40

mold

50

Air duct

52

Air scrubber

60

additional conditioning facility

70

Fresh air

80

Indoor air

100

Continuous casting plant

200

Hall

G

Pouring direction

Z

Conditioning facility

Z1

Heat exchanger

Z2

cooler

Z3

Dehumidifier

Z4

filter

Z6

mute

Z7_1

Exhaust air distribution flap (first distribution device)

Z7_2

Distribution flap return (second distribution device)

Z7_3

third distribution device

Z7_4

fourth distribution device

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102017209731 A1 [0002]
• DE 102015209399 A1 [0004]
• DE 102006045791 B4 [0005]

Claims (23)

Method for operating a cooling chamber (1) in a strand guide device (10) of a continuous casting system (100), comprising the following steps: redirecting a casting strand (13) cast with the aid of a mold (40) of the continuous casting system (100) in a strand guide device (1) downstream of the mold ( 10) to the horizontal; Cooling the casting strand (13) as it passes through the cooling chamber (1) within the strand guide device (2) by spraying the casting strand (13) with a coolant (33) to form steam (5) within the cooling chamber (1), the steam ( 5) at least together with sucked-in false air forms a steam-air mixture (5') which is at least partially saturated with the coolant (33); and suction and suction of the steam-air mixture (5 ') from the cooling chamber (1) with the aid of a suction device (20), which has an induced draft fan (8), a suction opening (3) opening into the cooling chamber (1) and a has a suction channel (7) connecting the suction opening (3) and the induced draft fan (8); characterized by depleting the steam-air mixture (5') using at least one separator (6). Procedure according to Claim 1 , characterized in that the steam-air mixture (5') is depleted within the separator (6) by condensation and/or droplet separation, preferably in conjunction with air rectification. Procedure according to Claim 1 or 2 , characterized in that the steam-air mixture (5') is depleted with the aid of the separator (6) arranged within the cooling chamber (1) in front of the suction opening (3) of the suction device (20); and characterized by the condensed steam-air mixture (5') flowing out of the separator (6) into a sewer (24) within the cooling chamber (1). Method according to one of the preceding claims, characterized in that the depletion of the steam-air mixture (5 ') alternatively or additionally with the aid of the separator (6) arranged in a suction channel (7) of the suction device (20) and/or another Separator (6 '), the suction channel (7) connecting the suction opening (3) and an induced draft fan (8) of the suction device (20) with each other. Method according to one of the preceding claims, characterized in that the depletion of the steam-air mixture (5 ') additionally takes place in front of, on or in the induced draft fan (8) of the suction device (20) by means of attachments and/or internals (16) on and/or in the induced draft fan (8), e.g. spray nozzles, a medium, e.g. B. an absorbent into which the extracted steam-air mixture (5 ') is introduced. Method according to one of the preceding claims, characterized in that the preconditioned steam-air mixture (5') is returned to the cooling chamber (1) to the extent of a first portion after passing through the induced draft fan; and/or is fed to a conditioning device (Z) to the extent of a second subset in order to be further conditioned there. Method according to one of the preceding claims, characterized in that the steam-air mixture (5') has a higher relative humidity than the air supplied to the cooling chamber. Method according to one of the preceding claims, characterized in that additional air (14) is blown into the cooling chamber (1) with the aid of a pressure fan (4), the pressure fan (4) preferably opposite the suction opening (3) of the suction device (20). is installed. Procedure according to Claim 8 , characterized in that the additional air is fresh air (70) sucked in from outside the hall (200), hall air (80) sucked in from the hall (200) and / or that from the cooling chamber (1, 1 ' ) sucked out steam-air mixture (5 ') preferably after it has already been preconditioned; and that the additional air (14) is generated by conditioning the extracted and preconditioned steam-air mixture (5') with the aid of a conditioning device (Z), and/or by using the fresh air (70) or the hall air (80). is conditioned with an additional conditioning device (60) before it is blown into the cooling chamber (1), the conditioning comprising - depending on requirements and depending on the condition of the sucked in air - at least one of the following measures: - Cooling and / or heating of the additional Air (14) by, for example, partial air recirculation or evaporative cooling, - increasing the humidity of the additional air (14) by partial air recirculation or media injection, - cleaning the additional air (14); - Depleting the pollutants in the additional air (14) by adding adsorbents. Procedure according to Claim 9 , characterized in that the preconditioned steam-air mixture (5') is in particular cooled, dehumidified and/or cleaned in the conditioning device (Z). Strand guiding device (10), comprising strand guiding rollers (2) for guiding a casting strand (13) cast with the aid of a mold (40) arranged upstream of the strand guiding device (10); a cooling device (30) with at least one cooling chamber (1) for cooling the casting strand (13) as it passes through the cooling chamber (1) by spraying the casting strand (13) with a coolant (33) to form a steam-air mixture ( 5') within the cooling chamber (1), the steam-air mixture (5') being at least partially saturated with the coolant (33); and a suction device (20), which has an induced draft fan (8), a suction opening (3) in the cooling chamber (1) and a suction channel (7) connecting the suction opening (3) to the induced draft fan (8), for suction and suction the steam-air mixture (5') from the cooling chamber (1); characterized by a separator (6, 6') for removing pollutants (33) from the sucked-in and sucked-out steam-air mixture (5'). Strand guide device (10). Claim 11 , characterized in that the separator (6) is arranged in front of the suction opening (3) of the suction device (20) in the cooling chamber (1, 1 ') for condensing the coolant (33) within the first and / or second cooling chamber (1, 1`); and that the cooling chamber (1) has a wastewater channel (24) for the condensate (22) to flow away. Strand guide device (10). Claim 11 , characterized in that the separator (6) is arranged in the suction channel (7) of the suction device (20). Strand guide device (10). Claim 12 or 13 , characterized in that a further separator (6 ') is arranged in the suction channel (7) of the suction device (20). Strand guide device according to one of the Claims 11 until 14 , characterized in that attachments and/or internals (16) are arranged in front of, on, in or behind the induced draft fan (8) for introducing a medium, in particular a separating agent or absorbent, into the steam-air mixture (5 '). Depleting the same in terms of dirt and/or pollutants. Strand guide device (10) according to one of the Claims 11 - 15 , characterized by a pressure fan (4) for blowing additional air (14) into the cooling chamber (1), the pressure fan (4) preferably being arranged opposite the suction opening (3) of the suction device (20) in the cooling chamber (1). Strand guide device (10) according to one of the Claims 11 - 16 , characterized by a first partial air return line (11) for returning at least a first portion of the preconditioned steam-air mixture (5 ') from the continued suction channel (9) into the cooling chamber (1). Strand guide device (10). Claim 17 , characterized by a first distribution device (Z7_1), in particular a first distribution flap, in the continued exhaust air duct (9), preferably at the outlet of the induced draft fan (8), for variably adjusting the first subset of the depleted or preconditioned steam-air mixture (5 '), which is led back into the cooling chamber (1) in a preconditioned manner via the first partial air return line (11), and a second portion of the depleted steam-air mixture, which is passed past the first partial air return line (11). Strand guide device (10). Claim 18 , characterized by a conditioning device (Z) connected downstream of the first distribution device (Z7_1) for receiving and conditioning the second subset of the extracted and preconditioned steam-air mixture, the conditioning device (Z) having at least one of the following components: a cooler (Z2 ) for cooling the second portion of the extracted steam-air mixture; a dehumidifier (Z3) for dehumidifying the cooled steam-air mixture, preferably by condensation; a filter (Z4) for cleaning the steam-air mixture; a heat exchanger (Z1) for reheating the dehumidified and/or cooled steam-air mixture, preferably by removing heat from the supplied second subset of the extracted steam-air mixture at the inlet of the conditioning device (Z) and for outputting a conditioned steam Air mixture (5"). Strand guide device (10). Claim 19 , characterized by one of the conditioning devices (Z). switched second distribution device (Z7_2) for variably adjusting a first and a second subset of the conditioned steam-air mixture (5") at the outlet of the conditioning device (Z); a second partial air return line (17) for guiding the first subset of the conditioned steam -Air mixture (5") back into the cooling chamber (1); and an output line (18) for directing the second portion of the conditioned steam-air mixture (5") into a hall (200) surrounding the strand guiding device (100) or to outside the hall (200) surrounding the strand guiding device. Strand guide device Claim 20 , characterized by a damper (Z6) connected downstream of the second distribution device (Z7_2) for dampening the flow noise of the second subset of the conditioned steam-air mixture in the output line (18). Strand guide device according to one of the Claims 11 until 21 , characterized in that a fourth distribution device (Z7_4) is provided for generating an air mixture at its output from received hall air (80) and fresh air (70) in a predetermined mixing ratio; that an additional conditioning device (60) is provided for conditioning the air mixture to reduce its dirt and pollutant content; and that a third distribution device (Z7_3) is arranged in the second partial air return line (17) for mixing the first subset of the conditioned steam-air mixture (5") with the conditioned air mixture in a predetermined mixing ratio to generate the additional in the cooling chamber (1, 1') to supply air (14). Strand guide device according to one of the Claims 11 - 22 , characterized in that the cooling device (30) has a first and a second cooling chamber (1, 1'), which are arranged one behind the other within the strand guide device (10) in the casting direction (G); that the first and second cooling chambers (1, 1') are connected to one another via an air duct (50); and that an air washer (52) is arranged in the air duct (50) for filtering and/or cleaning the steam-air mixture (5 ') flowing in the air duct (50) against the pouring direction (G), in particular from - opposite to first cooling chamber (1) - second cooling chamber (1`) arranged further downstream in the casting direction.

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