TWI729207B - Heating apparatus for inside of refractory vessel and heating method - Google Patents

Abstract

In a heating apparatus for inside of refractory vessel according to this invention, a lid member is disposed so as to cover an opening portion of an upper surface of a refractory container having at least an inner surface side made of a refractory material through a gap, and a burner provided to penetrate the lid member is used to heat the inside of the refractory container, which includes a continuous combustion control mechanism for adjusting the combustion amount while continuously burning fuel by the burner, and an on / off combustion control mechanism for adjusting the switching time and the combustion amount of the fuel by the burner, and which includes a switching device for switching combustion by the burner between the continuous combustion control mechanism and the on / off combustion control mechanism.

Description

Heating device and heating method inside refractory container

The present invention relates to a heating device and a heating method used in a refractory container such as a molten metal container, a tundish, and the like. The interior of the refractory container is made of refractory at least on the inner surface side. Specifically, it has the following characteristics: when heating the inside of the refractory container, the temperature rise inside the refractory container is appropriately controlled, and the entire interior of the refractory container can be appropriately heated.

Conventionally, in refractory containers made of refractories on at least the inner surface side used in molten metal containers, sprue hoppers, etc., the refractory on the inner surface side is regularly replaced.

In addition, after the refractory on the inner surface side of the refractory container is pasted as described above, a cover material is placed on the refractory container, and a burner that heats the inside of the refractory container is installed on the cover material, and by burning To heat and dry the inside of the refractory container.

At this time, on the upper edge of the outer surface of the refractory container, the raw material metal attached when the molten metal is poured and poured, forming unevenness, so the cover material cannot be closely attached, and the cover material is set to have a little Clearance.

Here, when the interior of the refractory container is heated and dried by the aforementioned burner as described above, the state of heating the interior of the refractory container (temperature or heating rate, etc.) must be appropriately set, for example, when the combustion is increased When the flame in the burner becomes larger and the entire interior of the refractory container is continuously and quickly heated, the moisture contained in the refractory on the inner surface side of the refractory container will be rapidly heated, and there will be refractory The object bursts due to the water vapor generated inside the refractory object. On the other hand, when reducing the amount of combustion in the burner to reduce the size of the flame, it will be difficult to fully heat the bottom of the refractory container, and it will take time to heat the entire interior of the refractory container. .

Furthermore, in the past, before injecting molten metal etc. into the interior of the refractory container, the burner was also used to heat the interior of the refractory container to reduce the temperature difference between the molten metal and the interior of the refractory container. In this case, the state of heating the interior of the refractory container must be appropriately set as described above, and the same problem exists.

Here, in the prior art, as shown in Patent Document 1, it is proposed to provide a cover material with a slight gap on the refractory container, and install the cover material to heat the inside of the refractory container. The heating burner is continuously measuring the amount of water contained in the refractory on the inner surface side of the refractory container, while the amount of combustion gas in the heating burner is controlled and dried, and the amount of water contained in the refractory becomes Starting from approximately zero time sequence, increase the amount of combustion gas to heat the burner to calcinate the refractory.

However, as shown in the aforementioned Patent Document 1, while continuously measuring the amount of moisture contained in the refractory on the inner surface side of the refractory container, while controlling the amount of combustion gas to heat the burner and drying, the control is very troublesome, and There are problems such as the following: the equipment cost will become very high, and it is difficult to quickly heat the refractory on the inner surface side of the refractory container, and it is difficult to appropriately control the temperature of the refractory on the inner surface side of the refractory container Variety.

In addition, Patent Document 2 proposes to calculate the fire resistance from the past multiple heating tracks of the refractory construction body of the same type as the refractory construction body that is currently to be heated, and to calculate the refractory temperature for multiple different specific temperatures The calculation of the average value of the stable temperature and the heating gas flow rate when the temperature of the construction body is stabilized near a specific temperature, to find the matching of the heating gas flow rate corresponding to each specific temperature, and based on the above-mentioned method The pairing of a plurality of specific temperatures and the heating gas flow rate is used to set the heating gas flow setting value corresponding to the current heating target temperature mode, and the flow rate of the heating gas is the aforementioned setting value. Perform control, while heating the refractory construction body, calculate the temperature difference between the measured temperature when the refractory construction body is heated and maintain a certain temperature and the aforementioned target temperature, and make the flow rate of the heating gas based on the aforementioned temperature difference By this change, the refractory construction body is heated to the target temperature, and the refractory is dried.

However, in the proposal shown in the aforementioned Patent Document 2, since the refractory construction body is heated to a predetermined target temperature and dried, the control becomes very troublesome, and the equipment cost becomes very high. As shown in the aforementioned Patent Document 1, when a gap is provided between the refractory construction body and the cover, there are the following problems: the temperature does not rise easily, it is difficult to quickly heat the refractory inside the refractory construction body, and it is difficult to properly heat the refractory inside the refractory construction body. Ground control of the temperature change of the refractory in the refractory construction body.

(Prior technical literature) (Patent Document)

Patent Document 1: Japanese Patent Application Publication No. 11-92236

Patent Document 2: Japanese Patent Laid-Open No. 2003-240446

The subject of the present invention is to solve the aforementioned problems when heating the inside of a refractory container composed of refractories on at least the inner surface side, and the subject is to appropriately control the refractory when heating the inside of the refractory container The temperature inside the container rises, and the whole inside of the refractory container can be appropriately heated.

In the heating device inside the refractory container of the present invention, in order to solve the aforementioned problems, the heating device inside the refractory container covers at least the opening of the upper surface of the refractory container made of refractory on the inner surface side with a gap therebetween. The upper part is provided with a cover material, and a burner that heats the inside of the refractory container is installed through the cover material. The heating device inside the refractory container is provided with a continuous combustion control mechanism, which is achieved by the aforementioned combustion The burner continuously burns the fuel while adjusting the amount of combustion; and the on/off combustion control mechanism adjusts the switching time and the amount of combustion between the combustion and the stop of the fuel performed by the burner; and a switching device is provided, the switching device The combustion by the burner is switched between the continuous combustion control mechanism and the on/off combustion control mechanism.

In this way, when the interior of the refractory container is heated by the combustion performed by the burner, in response to the condition of the interior heating of the refractory container, the switching device can be used in the continuous combustion control mechanism and the conduction/ The combustion control mechanism is turned off to appropriately switch the combustion performed by the combustor.

In addition, in the heating device inside the refractory container of the present invention, a temperature measuring device is provided on the lid material, and the above-mentioned combustion can be made by switching the device according to the temperature measured by the temperature measuring device as described above. The combustion of the device is switched between the aforementioned continuous combustion control mechanism and the on/off combustion control mechanism.

In addition, in the method for heating the inside of the refractory container of the present invention, until the inside of the refractory container rises to a predetermined temperature (the heat transfer mode is a low temperature region dominated by convection), the switching device utilizes the aforementioned on/off The off-combustion control mechanism performs the combustion by the aforementioned burner to make the inside of the refractory container conduct convective heat transfer. On the other hand, when the inside of the refractory container becomes higher than a predetermined temperature (the heat transfer form is high temperature dominated by radiation) Zone), by the aforementioned switching device, the aforementioned continuous combustion control mechanism is used to perform combustion by the aforementioned burner, and the inside of the refractory container is radiatively transferred. In this way, until the inside of the refractory container rises to a predetermined temperature, the combustion by the burner is performed by the on/off combustion control mechanism, and the inside of the refractory container is convectively transferred. When the cover material is equipped with a temperature measuring device, the temperature of the entire interior of the refractory container can also be measured uniformly and efficiently.

Furthermore, in the method for heating the inside of a refractory container of the present invention, when the inside of the refractory container becomes a predetermined temperature or higher, the continuous combustion control mechanism is used to perform combustion by the burner, and heat is transferred by radiation When the inside of the refractory container is maintained at a certain temperature, when the amount of fuel supplied to the burner reaches the turndown limit, the switching device changes the combustion performed by the burner from the continuous combustion The control mechanism switches to on/off the combustion control mechanism and reduces the amount of fuel to control the combustion in a way that does not reach the limit of the burner.

In the heating device for the inside of the refractory container of the present invention, when the interior of the refractory container is heated by burning fuel by the burner as described above, in response to the condition of the internal heating of the refractory container, the switching device is used, The combustion by the aforementioned burner is appropriately switched between the continuous combustion control mechanism and the on/off combustion control mechanism, and the temperature rise inside the refractory container is appropriately controlled, so that the entire interior of the refractory container can be appropriately adjusted Ground heating.

In addition, as in the method for heating the inside of a refractory container of the present invention, until the inside of the refractory container rises to a predetermined temperature, the switching device uses the on/off combustion control mechanism to perform combustion by the burner, When convective heat transfer is performed inside the refractory container, even if the amount of combustion is increased to increase the flame of the burner, when the entire interior of the refractory container is heated, the flame is turned off, so it is not The moisture contained in the refractory on the inner surface side of the refractory container may be heated rapidly, causing the refractory to burst. In addition, when the inside of the refractory container reaches a predetermined temperature or higher, the continuous combustion control mechanism is used to continuously perform combustion by the burner through the aforementioned switching device, and the inside of the refractory container is radiatively transferred even in the refractory container. There is a gap between the upper surface of the refractory container and the lid material, and the internal temperature of the refractory container can also be appropriately raised or maintained.

10‧‧‧Refractory container

11‧‧‧Outer wall

12‧‧‧Refractory

20‧‧‧Cover material

21‧‧‧Burner

22‧‧‧Temperature measuring device

30‧‧‧Control device

31‧‧‧Continuous combustion control mechanism

32‧‧‧Turn on/off the combustion control mechanism

33‧‧‧Switching device

s‧‧‧Gap

Fig. 1 is a schematic explanatory diagram showing a heating device inside a refractory container according to an embodiment of the present invention.

Figure 2 shows the heating device inside the refractory container of the foregoing embodiment, and the combustion state of the burner that heats the interior of the refractory container is controlled by the switching device using the on/off combustion control mechanism. Figure 2 (A) is a schematic explanatory diagram showing a state in which combustion is increased by turning on/off the combustion control mechanism, and Figure 2 (B) is a diagram showing that the combustion is stopped by turning on/off the combustion control mechanism A schematic illustration of its state.

Fig. 3 shows the heating device inside the refractory container of the aforementioned embodiment, and the continuous combustion control mechanism is used to control the combustion state of the burner that heats the interior of the refractory container by the switching device. Fig. 3(A) It is a schematic explanatory diagram showing a state in which the combustion amount is reduced by the continuous combustion control mechanism to perform combustion, and Fig. 3(B) is a schematic explanatory diagram showing a state in which the combustion amount is increased by the continuous combustion control mechanism to perform combustion.

Figure 4 shows the heating device inside the refractory container of the foregoing embodiment, in a manner that does not reduce the combustion of the burner that heats the interior of the refractory container, by switching the device, the combustion control mechanism is turned on/off. Fig. 4(A) is a schematic explanatory diagram showing the state of reducing the amount of combustion to perform combustion, and Fig. 4(B) is a schematic explanatory diagram showing the state of stopping the aforementioned combustion.

Figure 5 shows that in order to use the heating device inside the refractory container of the previous embodiment, the temperature inside the refractory container is controlled by following the target temperature line, and is switched by the switching device: ON/OFF of the combustion control mechanism , And a schematic explanatory diagram of an example of a burner that controls heating of the inside of a refractory container by a continuous combustion control mechanism.

Hereinafter, the heating device and heating method inside the refractory container according to the embodiment of the present invention will be specifically explained based on the schematic diagram. In addition, the heating device and heating method inside the refractory container of the present invention are not limited to the following embodiments, and can be implemented with appropriate changes within the scope of not changing the gist of the present invention.

In the heating device inside the refractory container of this embodiment, as shown in Fig. 1 and the like, the refractory container 10 is in the shape of a pot with an open upper surface, and is formed on the inner surface of the outer wall 11 made of steel or the like. Installed with 12 refractories.

In addition, the cover material 20 is arranged to cover the opening of the upper surface of the refractory container 10 with a gap s (approximately 10 to 20 cm) therebetween, and a burner 21 and a temperature measuring device 22 are installed. The device 21 penetrates the lid 20 and heats the inside of the refractory container 10, the temperature measuring device 22 measures the internal temperature of the refractory container 10, and the temperature of the refractory container 10 measured by the temperature measuring device 22 The internal temperature is output to the control device 30.

Furthermore, in this embodiment, the burner 21 is provided with a continuous combustion control mechanism 31, and an on/off combustion control mechanism 32. The continuous combustion control mechanism 31 is configured to continuously maintain fuel by the burner 21. Combustion, while adjusting the amount of combustion, the on/off combustion control mechanism 32 adjusts the switching time and the amount of combustion between the combustion and the stop of the fuel by the burner 21; and a switching device 33 is provided, the switching device 33 The combustion by the burner 21 is switched between the continuous combustion control mechanism 31 and the on/off combustion control mechanism 32.

In addition, in this embodiment, the internal temperature of the refractory container 10 measured by the temperature measuring device 22 is output to the control device 30 as described above, and in response to the internal heating conditions of the refractory container 10, this control The device 30 controls the switching device 33 to switch the combustion performed by the combustor 21 between the continuous combustion control mechanism 31 and the on/off combustion control mechanism 32.

Here, in this embodiment, for example, until the internal temperature of the refractory container 10 measured by the temperature measuring device 22 reaches a predetermined temperature, the switching device 33 is controlled by the control device 30, and the switching device 33 is turned on/off. Turn off the combustion control mechanism 32 to adjust the switching time and the amount of combustion between the combustion and the stop of the fuel by the combustor 21. As shown in Figure 2 (A) and Figure 2 (B), the burner 21 is added The amount of combustion is switched at an appropriate timing: a state in which the flame is increased for combustion, and a state in which the aforementioned combustion is stopped.

In this way, as shown in Figure 2 (A), in the state of increasing the amount of combustion in the burner 21 to make the flame larger and burning, the entire interior of the refractory container 10 is heated and convective heat transfer is formed. On the other hand, as shown in Figure 2(B), the combustion is stopped at the appropriate timing as described above, so that the following situations will not occur: excessive heating of the entire interior of the refractory container 10, and rapid heating of the refractory container 10 The moisture contained in the refractory 12 on the inner surface side may cause the refractory to burst.

Furthermore, if the combustion amount in the burner 21 is increased as shown in Fig. 2(A) to increase the flame size and the combustion time is increased, as shown in Fig. 2(B), the combustion is at an appropriate timing. During the stop time, the entire interior of the refractory container 10 will not be overheated. The interior of the refractory container 10 can be heated by convective heat transfer so that the entire interior of the refractory container 10 becomes a certain temperature .

Furthermore, after the entire interior of the refractory container 10 is heated to a certain temperature in the aforementioned manner, the aforementioned control device 30 controls the switching device 33 to further heat the interior of the refractory container 10, and is controlled by continuous combustion The mechanism 31 adjusts the amount of combustion in a state where the fuel is continuously burned by the burner 21, and can reduce the amount of combustion of the burner 21 and reduce the flame as shown in Figure 3 (A) and Figure 3 (B). Keep the internal temperature of the refractory container 10 small for continuous combustion, or increase the burning amount of the burner 21 to increase the flame and increase the internal temperature of the refractory container 10 to a predetermined temperature. combustion. In addition, the continuous combustion control mechanism 31 uses the continuous combustion control mechanism 31 to perform continuous combustion of the fuel using the burner 21 as described above. Therefore, no external air will pass through the gap s between the upper surface of the refractory container 10 and the aforementioned lid material 20. When it flows into the refractory container 10, the internal temperature of the refractory container 10 can be prevented from decreasing.

Furthermore, as shown in Figure 3(A), in the case of continuous combustion in a manner that reduces the amount of combustion in the burner 21, reduces the flame, and keeps the internal temperature of the refractory container 10 constant, When there is a need to further reduce the amount of combustion in the combustor 21, and the lower limit of the continuous combustion of the combustor 21 is exceeded, the switching device 33 is controlled by the control device 30, and the continuous combustion control mechanism 31 is switched The combustion control mechanism 32 is turned on/off, and can be switched at an appropriate timing as shown in Figure 4 (A) and Figure 4 (B): reduce the burner in a way that does not exceed the lower limit of the reduction The amount of combustion of 21 and the state of the flame and the state in which it is burned, and the state in which the combustion is stopped.

Furthermore, using the heating device inside the refractory container described above, an example of controlling the temperature inside the refractory container 10 in accordance with the target temperature line shown in FIG. 5 will be described.

Here, when using the aforementioned heating device inside the refractory container, the burner 21 is used to heat the inside of the refractory container 10, and the inside of the refractory container 10 is controlled by the target temperature line shown in Fig. 5 At the temperature, first increase the amount of combustion of the burner 21 as shown in the above-mentioned 2nd (A) and 2nd (B), and switch at an appropriate timing: the state of burning (conducting) so that the flame becomes larger ), and the state of stopping the combustion (off), and the internal temperature of the refractory container 10 is raised at a predetermined heating rate by convective heat transfer, so that the refractory will not be caused by the refractory 12 in the refractory container 10 The contained moisture bursts, and the inside of the refractory container 10 is heated to the first predetermined temperature. Then, in such a way that the time for stopping the combustion of the burner 21 is prolonged compared with the aforementioned temperature increase, the entire interior of the refractory container 10 is uniformly controlled to the first predetermined temperature by convective heat transfer. In addition, these controls are actually conducted for many times of on/off for a long period of time, but they are briefly shown in Figure 5.

In addition, after the entire interior of the refractory container 10 is heated to the first predetermined temperature in a manner that does not cause the explosion of the refractory, the switching device 33 is controlled by the control device 30 as described above, and the continuous combustion control mechanism 31. As shown in Fig. 3(A) and Fig. 3(B), adjust the burning amount of the fuel continuously burned by the burner 21, so that the internal temperature of the refractory container 10 rises to the second at a predetermined heating rate. The predetermined temperature is then maintained at the second predetermined temperature in the internal temperature of the refractory container 10. Here, the continuous combustion control mechanism 31 uses the burner 21 to continuously burn the fuel as described above. Therefore, as described above, the outside air does not flow into the gap s between the upper surface of the refractory container 10 and the lid material 20. In the refractory container 10, the internal temperature of the refractory container 10 can be prevented from decreasing.

In addition, when the fuel is continuously burned by the burner 21 and maintained at the second predetermined temperature as described above, if the combustion volume of the combustor 21 is relatively large and it is difficult to maintain the second predetermined temperature, the continuous combustion must be exceeded. When the lower limit of the combustor 21 is lowered, the continuous combustion control mechanism 31 is switched to the on/off combustion control mechanism 32, and as shown in Figure 4 (A) and Figure 4 (B), it will not The amount of combustion and flame of the burner 21 are reduced by exceeding the lower limit of the reduction, and switched at an appropriate timing: the state of burning and the state of stopping the combustion, so as to maintain the second predetermined temperature.

10‧‧‧Refractory container

11‧‧‧Outer wall

12‧‧‧Refractory

20‧‧‧Cover material

21‧‧‧Burner

22‧‧‧Temperature measuring device

30‧‧‧Control device

31‧‧‧Continuous combustion control mechanism

32‧‧‧Turn on/off the combustion control mechanism

33‧‧‧Switching device

s‧‧‧Gap

Claims (3)

A heating device inside a refractory container is provided with a cover material so as to cover at least the opening part of the upper surface of the refractory container made of refractory on the inner surface side with a gap, and penetrate through the cover material A burner for heating the inside of the refractory container is provided; the heating device inside the refractory container is provided with: a continuous combustion control mechanism, which adjusts the amount of combustion while the fuel is continuously burned by the burner; and on/off The combustion-off control mechanism adjusts the switching time and the amount of combustion between the combustion and the stop of the fuel by the burner; and is provided with a switching device that is connected to the continuous combustion control mechanism and the on/off combustion control mechanism Switch between the combustion performed by the burner; the cover material is provided with a temperature measuring device, and based on the temperature measured by the temperature measuring device, the switching device is used to switch between the continuous combustion control mechanism and the on/off The combustion by the aforementioned burner is switched between the off-combustion control mechanism. A method for heating the inside of a refractory container, which uses the heating device inside the refractory container described in item 1 of the scope of patent application, the method of heating the inside of the refractory container, the heating method is: until the inside of the refractory container rises to a predetermined temperature So far, by the aforementioned switching device, the aforementioned on/off combustion control mechanism is used to perform combustion by the aforementioned burner, so that the inside of the refractory container is convectively transferred. On the other hand, when the inside of the refractory container reaches a predetermined temperature In the above, by the aforementioned switching device, the aforementioned continuous combustion control mechanism is used to carry out the forwarding The combustion performed by the burner causes radiation heat transfer inside the refractory container. The method for heating the inside of a refractory container as described in the scope of patent application 2, wherein when the inside of the refractory container becomes a predetermined temperature or higher, the continuous combustion control mechanism is used to perform combustion by the burner, and by When the inside of the refractory container is maintained at a certain temperature by radiant heat transfer, when the amount of fuel supplied to the burner reaches the drop limit, the switching device switches the combustion performed by the burner to the conduction /Turn off the combustion control mechanism, and control the combustion in a state that does not reach the limit of the combustor.

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