JP2978425B2 - Stirring method, stirrer and furnace in furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a ceramic product,
The present invention relates to a stirring method and a stirring device in a furnace used in a technical field such as firing of ceramic products, and a furnace using the same.

[0002]

2. Description of the Related Art In a furnace used for firing ceramic products and ceramic products, it is preferable to stir the inside of the furnace in order to make the temperature distribution in the furnace uniform. Therefore, as shown in FIG. 6, a stirring fan 2 is conventionally installed on the ceiling of the furnace body 1,
A method of stirring the inside of the furnace was used. However, when the stirring fan 2 is made of metal, its use limit is 700 ° C. to 900 ° C., and it cannot be used in a medium to high temperature range. Further, if the stirring fan 2 is made of ceramic, the temperature range in which it can be used is widened, but it is expensive and the reliability is insufficient. Further, when the furnace body 1 becomes large, it is not possible to sufficiently stir with this method.

As shown in FIG. 7, burners 3 are alternately provided above and below a furnace body 1, and the inside of the furnace is agitated by a burner frame. However, in this method, when sufficient stirring is performed, the amount of gas in the furnace increases and the temperature in the furnace increases. If excess air is supplied to the burner 3 in order to suppress a rise in temperature, the amount of gas further increases, and the burden on exhaust gas treatment equipment and the like increases.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and can uniformly stir the inside of the furnace without increasing the amount of gas in the furnace. The present invention has been made in order to provide a stirring method and a stirring apparatus in a furnace which can be used, and a furnace using the same.

[0005]

According to the present invention, there is provided a method for stirring a gas in a furnace, comprising the steps of:
Through the heat accumulator forming the regenerator paired after having sucked through the regenerator from one entrance to be connected to the furnace body out of the other
The step of blowing the gas into the furnace again from the inlet is repeated while reversing the gas circulation direction. Further, the stirrer in the furnace of the present invention connects the gas in the furnace to the furnace body.
A gas circulation path that is sucked from one of the entrances and then blown back into the furnace from the other entrance and exit is provided with a circulation fan and a switching valve for reversing the gas circulation direction,
It is characterized in that a pair of regenerators in a portion of the entrance of the gas circulation path. Further, the furnace according to the present invention is characterized in that the above-described stirring device in the furnace is arranged in a medium temperature range.

[0006]

Embodiments of the present invention will be described below in more detail with reference to the drawings. FIG. 1 shows a basic embodiment of the present invention, in which 1 is a furnace body, and 4 is a gas circulation path which sucks gas in the furnace and blows the gas into the furnace again. The gas circulation path 4 includes a circulation fan 5 and a switching valve 6, and a pair of heat accumulators 7 and 8 made of a heat-resistant material such as ceramics at an entrance and exit connected to the furnace body 1.

[0007] The switching valve 6 is switched at a period shorter e.g. of about 30 seconds, and has a function of inverting the direction of circulation of the gas, gas furnace body 1 in high temperatures in the furnace in the state of FIG. 1
From one entrance to be connected is sucked into the circulation fan 5 through the regenerator 8 to be blown again into the furnace through the regenerator 7 from the other entrance. During this time, the regenerator 8 is heated to a high temperature. Next, when the circulation direction of the gas is reversed, the circulating gas sucked through the regenerator 7 is heated by the regenerator 8 and then blown into the furnace from the opposite entrance .

As described above, according to the method and apparatus for stirring the inside of the furnace of the present invention, the furnace gas sucked from the furnace is circulated in the direction of circulation.
Since it is possible to stir the inside of the furnace by directly blowing it into the furnace while inverting it, uniform stirring can be performed without increasing the amount of gas in the furnace. The high-temperature gas in the furnace is cooled by the heat accumulators 7 and 8 and then cooled by the gas circulation path 4.
And the temperature rises again and returns to the inside of the furnace, so that the heat loss is small and the regenerators 7 and 8 are provided at the entrance and exit of the gas circulation path 4 to flow through the circulation fan 5 and the switching valve 6. The gas temperature can be kept much lower (for example, 300 ° C.) than the furnace temperature (for example, 1200 ° C.), and these materials can be made of metal.

FIG. 2 is a diagram in which the single rotary type switching valve 6 in FIG. 1 is replaced with a switching valve 6 composed of four valves. However, its function is the same as that described with reference to FIG.

FIGS. 3 and 4 show a gas circulating passage 4 in FIGS. 1 and 2 in which a gas heating means 9 is provided at a portion outside the regenerators 7 and 8 relative to the furnace. The heating means 9 may be a direct heating means such as a burner or an indirect heating means such as a heat exchanger. Such a gas heating means 9 has a function of preventing the temperature of the circulating gas from decreasing when the gas circulation path 4 outside the furnace is long and the amount of heat radiation is large. Moreover, since the heating means 9 is provided at a lower temperature side of the furnace than the regenerators 7 and 8, there is an advantage that special heat resistance is not required. The number of the heating means 9 may be one as shown by a solid line, or two or more as shown by a chain line. When the inside of the furnace is to be cooled, a cooling means can be provided instead of the heating means 9. By providing such heating means 9 and cooling means, it is possible to control the temperature inside the furnace while stirring the inside of the furnace.

FIG. 5 shows a furnace in which the above-described stirrer in the furnace is arranged in a medium temperature range. This furnace is a ceramic furnace for preheating, firing and cooling in order from the right side.
A stirrer 11 is provided for sucking the gas inside the furnace and ejecting it into the furnace from the opposite side. However, this stirrer 11 has a problem of heat resistance of the fan 10 in the middle temperature range where the temperature in the furnace rises to 700 ° C. or more. Therefore, the stirrer provided with the heat storage units 7 and 8 of the present invention is used in the middle temperature range. Are located. Note that in a high temperature range in which firing is performed, stirring in a furnace by a large number of burners 12 is employed.

In the furnace configured as described above, the inside of the furnace can be sufficiently agitated in the middle temperature range, so that the firing with a favorable temperature distribution shown by hatching in FIG. 5 can be performed. However, in the prior art, the stirring in the furnace in the middle temperature range was insufficient and the system was won, so that a favorable temperature distribution could not be obtained as shown by the hatching in FIG. For this reason, according to the furnace of the present invention, it is possible to perform more uniform firing than before, and it is possible to improve the firing quality. In FIG. 5, the stirrer provided with the regenerators 7 and 8 of the present invention is arranged on the preheating side, but the stirrer of the present invention can be arranged on the cooling side depending on the product, and the stirrer of the present invention can be arranged in a high temperature region. It goes without saying that a stirring device may be provided.

[0013]

As described above, according to the present invention, the inside of the furnace can be uniformly stirred without increasing the gas amount in the furnace, and the stirring in the medium temperature range to the high temperature range can be performed. There is also an advantage that can be performed. Therefore, the present invention is particularly valuable in the technical field of firing ceramic products and ceramic products, which need to strictly observe the firing temperature curve in a middle temperature range or a high temperature range.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a basic embodiment of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the present invention.

FIG. 3 is a cross-sectional view showing another embodiment of the present invention.

FIG. 4 is a cross-sectional view showing another embodiment of the present invention.

FIG. 5 is a plan view showing an embodiment of the invention of claim 4;

FIG. 6 is a sectional view showing a conventional example.

FIG. 7 is a sectional view showing another conventional example.

[Description of Signs] 1 furnace body, 2 stirring fan, 3 burner, 4 gas circulation path, 5 circulation fan, 6 switching valve, 7 heat storage device, 8 heat storage device, 9 heating means, 10 fan, 11 stirring device, 12 burner

Claims (4)

(57) [Claims] The gas in the furnace is connected to one of the outlets connected to the furnace body.
A process in which the process of sucking the gas from the inlet through the regenerator and blowing it into the furnace again from the other port through the regenerator paired with the regenerator is repeated while reversing the gas circulation direction. Stirring method. 2. The gas in the furnace is connected to one of the outlets connected to the furnace body.
A gas circulation path blown from the other entrance after having sucked from the inlet to again furnace, circulation fan and, provided with a switching valve for reversing the direction of circulation of the gas, a pair of heat storage in the portion of the entrance of the gas circulation path A stirrer in a furnace, provided with a vessel. 3. The stirrer in a furnace according to claim 2, wherein a gas heating or cooling means is provided in a portion of the gas circulation path outside the furnace with respect to the regenerator. 4. A furnace, wherein the stirrer in the furnace according to claim 2 or 3 is arranged in a medium temperature range.