JP2001248974A - High temperature atmospheric gas generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high temperature atmospheric gas while eliminating a disadvantage of a conventional apparatus. SOLUTION: Thermal storage materials 5a, 5b are divided into two or more pieces and rotated around their axes. A burner 6 is disposed in a combustion chamber 2a in which the material 5a of the rotated materials is present. Fuel and combustion air supply routes 9, 10 to the burner 6 as well as a combustion exhaust gas exhaust route 12 are provided. Reducible atmospheric gas supply and exhaust routes 13, 14 communicate with a thermal storage chamber 2b in which the other material 5b is present. In the chamber 2a, the material 5a in the chamber 2a is heated by a high temperature gas obtained by burning by the burner 6. And, the material 5b previously heated in the chamber 2a is heated by passing the reducible atmospheric gas to the chamber 5b. These operations are alternately switched. Thus, constituting components of this high temperature atmospheric gas generator can be remarkably reduced, and its manufacturing cost can be decreased. Further, the generator can be decreased in size as compared with a conventional apparatus and can be installed in a place having a narrow mounting space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-temperature non-oxidizing atmosphere blown into a furnace such as a heating furnace, a heat treatment furnace or a melting furnace which needs to heat and melt an object to be heated while maintaining a non-oxidizing or reducing atmosphere. The present invention relates to a high-temperature atmosphere gas generator for obtaining a gas or a reducing gas.

[0002]

2. Description of the Related Art Combustion in a heating furnace, a heat treatment furnace, a melting furnace, or the like generally involves complete combustion of fuel at an air ratio of 1.0 or more, so oxidation of an object to be heated is inevitable. Therefore, scale loss occurs in the furnace, and various problems resulting from a decrease in yield and oxidation in the furnace occur. Therefore, in order to suppress such a problem, there is a method of heating by blowing a non-oxidizing atmosphere gas or a reducing gas heated to a high temperature.

[0003] As an apparatus for obtaining a non-oxidizing atmosphere gas or a reducing gas preheated to a high temperature, Japanese Patent Application Laid-Open No. 9-4785 discloses an apparatus.
In No. 1, at least two regenerative preheaters each having a combustion chamber and a heat storage chamber are provided, and a fuel gas switching valve for selectively supplying fuel gas to each combustion chamber of the regenerative preheater and a combustion air are selected. In addition, an exhaust gas switching valve for selectively opening to the atmosphere and a non-oxidizing atmosphere gas switching valve for selectively supplying a non-oxidizing atmosphere gas are provided in each heat storage chamber. In each of the regenerative preheaters, the corresponding fuel gas switching valve, combustion air switching valve and exhaust switching valve are opened, the non-oxidizing atmosphere gas switching valve is closed, and the fuel gas is burned in the combustion chamber. Heating the heat storage chamber and releasing the exhaust gas to the atmosphere through the exhaust switching valve, closing the fuel switching valve, combustion air switching valve and exhaust switching valve, and opening the non-oxidizing atmosphere gas switching valve Add non-oxidizing atmosphere gas It has been obtained a non-oxidizing atmosphere gas heated to a high temperature via the combustion chamber operation and heat-retaining device which was repeated configured alternately is proposed.

[0004]

However, in such a heat retention device (hereinafter referred to as "conventional device") proposed in Japanese Patent Application Laid-Open No. 9-47851, at least two burners are required and each heat storage device is required. A fuel switching valve, a combustion air switching valve, an exhaust switching valve, a non-oxidizing atmosphere gas switching valve, a pipe attached to each switching valve, and a control circuit for opening and closing each switching valve are required. For this reason, the manufacturing cost of the apparatus is added, and the apparatus is large, so that it may not be applicable in a place where there is no handling space.

The present invention solves the above-mentioned drawbacks of the conventional apparatus, and requires a heating furnace, a heat treatment furnace, and a melting furnace which need to heat and melt an object to be heated while maintaining a non-oxidizing or reducing atmosphere. It is an object of the present invention to provide a high-temperature atmosphere gas generator capable of obtaining a high-temperature non-oxidizing atmosphere gas or a reducing atmosphere gas blown into a furnace such as the above.

[0006]

In order to achieve the above object, a high-temperature atmosphere gas generating apparatus according to the present invention comprises a heat storage element divided into at least two parts, and rotating or circulating the heat storage element around its axis. A burner disposed in a combustion chamber in which one of the heat storage bodies is present in the rotation or circulation process, a supply path of fuel and combustion air to the burner and a discharge path of combustion exhaust gas, and the other heat storage. A supply path and a discharge path for the reducing atmosphere gas communicated with the heat storage chamber in which the body exists are provided. By doing so, in the combustion chamber, the regenerator existing in the combustion chamber is heated by the high-temperature gas burned by the burner, and in the regenerator, the reducing atmosphere gas passes through the regenerator heated in the combustion chamber. If the heating operation is alternately switched, a high-temperature atmosphere gas can be continuously generated.

[0007]

DETAILED DESCRIPTION OF THE INVENTION A high-temperature atmosphere gas generating apparatus according to the present invention comprises a heat storage element divided into at least two parts, a mechanism for rotating or circulating the heat storage element around its axis, and a mechanism for rotating or circulating the heat storage element. A burner disposed in a combustion chamber in which a heat storage material exists, a supply path of fuel and combustion air to the burner, and a discharge path of combustion exhaust gas, and a reduction communicating with the heat storage chamber in which the other heat storage material also exists. The combustion chamber is provided with a supply and discharge path for a reducing atmosphere gas. In the combustion chamber, the regenerator present in the combustion chamber is heated by the high-temperature gas burned by the burner. The operation of heating by passing through is alternately switched to continuously generate a high-temperature atmosphere gas.

The high-temperature atmosphere gas generating apparatus according to the present invention rotates or circulates at least two or more divided heat accumulators around its axis. In the combustion chamber where one of the heat accumulators is present in the rotation or circulation process, a burner is provided. Heating the heat storage body present in the combustion chamber with the high-temperature gas burned in the above, and in the heat storage chamber in which the other heat storage body is also present, the operation of heating by passing the reducing atmosphere gas through the heat storage body heated in the combustion chamber is performed. Since the switching is performed alternately, it is possible to continuously generate a high-temperature atmosphere gas.

In the high-temperature atmosphere gas generating apparatus according to the present invention, by adopting the above-mentioned structure, one burner is sufficient instead of the conventional apparatus which requires at least two burners. The connecting fuel switching valve, combustion air switching valve, exhaust switching valve, non-oxidizing atmosphere gas switching valve, piping attached to each switching valve, and a control circuit for opening and closing each switching valve are not required.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a high-temperature atmosphere gas generating apparatus according to the present invention will be described.
In the tundish for continuous casting, while the standby from the end of the casting to the start of the next continuous casting, the heated N ₂ gas is blown into the tundish to maintain the temperature in the tundish and, after casting, to the inside of the tundish. An example in which the present invention is applied to a tundish non-oxidizing heat retention for the purpose of preventing the remaining steel from being oxidized will be described with reference to FIGS. FIG. 1 is a schematic structural view of the entire high-temperature atmosphere gas generator of the present invention, FIG. 2 is a schematic structural view of a high-temperature atmosphere gas generator main body of the present invention, and FIG.
(B) is AA sectional drawing of (a).

1 and 2, reference numeral 1 denotes a high-temperature atmosphere gas generating apparatus according to the present invention, which has the following configuration.
Reference numeral 2 denotes a cylindrical outer casing whose inner surface is covered with a heat insulating material 3, the inside of which is divided into, for example, a combustion chamber 2a and a heat storage chamber 2b by a partition plate 4b to be described later. The container 4 is provided coaxially and rotatably about the axis.

The container 4 has a bottom surface formed of a support grid 4a made of, for example, stainless steel, and the inside thereof is divided into two by a partition plate 4b as shown in FIG. 500 kg of, for example, alumina balls having a particle size of 15 mm as heat storage elements 5a and 5b inside the storage medium.
Is filled. In this embodiment, the partition plate 4b
Is vertically extended to divide the inside of the outer casing 2 into two, a combustion chamber 2a and a heat storage chamber 2b.

Reference numeral 6 denotes a rotary shaft disposed at an axial position of the outer casing 2 and the container 4 so as to penetrate the outer casing 2 and the container 4. The rotary shaft 6 is rotated by, for example, 180 ° forward and backward by an actuator 7 attached to one end (the upper end in this embodiment). It is rotated, and this rotation axis 6
The container 4 integrally mounted on the container is similarly rotated forward and backward by 180 °.

Reference numeral 8 denotes, for example, 280 provided in the combustion chamber 2a.
The burner has a capacity of 0 MJ / h, and includes a fuel supply path 9 and a combustion air supply path 10. this house,
An orifice 9 for measuring a fuel flow rate is provided in the fuel supply path 9.
a, and a fuel flow rate controller 9c for outputting a setting signal to the fuel flow rate control valve 9b so that the command signal of the orifice 9a becomes a preset fuel flow rate. The setting signal from the fuel flow rate controller 9c is provided. Thus, the amount of burning of the burner 8 is controlled.

Similarly to the fuel supply passage 9, the combustion air supply passage 10 has an orifice 10a for measuring the combustion air flow, a combustion air flow control valve 10b, and a combustion air flow control controller 10c. Is provided from the combustion air flow rate controller 10c so that the instruction signal of the orifice 10a becomes the air ratio set by the ratio setter 11 based on the setting signal from the fuel flow rate controller 9c. A setting signal is output to the combustion air flow control valve 10b,
It is controlled.

Reference numeral 12 denotes a heat storage element 5a in the combustion chamber 2a.
Is a discharge path of the combustion exhaust gas communicated on the opposite side to the burner 8 through the air blower.
2a is interposed.

Reference numeral 13 denotes a supply path of a reducing atmosphere gas, for example, N ₂ gas, which communicates with the heat storage chamber 2b. Reference numeral 14 also communicates with the N ₂ gas supply path 13 via the heat storage body 5b in the heat storage chamber 2b. a discharge path has been N ₂ gas, the N ₂ gas exhaust passage 14, for example a height of 1.6
tundish 1 with inner dimensions of m, length 5m, width 1m
It is led to 5. Then, the supply path 13 of these N ₂ gas, an orifice 13a for measuring the flow rate of N ₂ gas
If, as the measurements from the orifice 13a is a flow rate which is set in advance, and a N ₂ gas flow controllers 13c to operate the N ₂ gas flow rate control valve 13b.

Reference numeral 16 denotes a seal plate disposed at a portion of the outer casing 2 which is in contact with the partition plate 4b in order to prevent leakage of combustion gas from the combustion chamber 2a to the heat storage chamber 2b. It is a seal plate for preventing a part of the N ₂ gas from entering between the container 4 and the heat insulating material 3.

The high-temperature atmosphere gas generator 1 of the present invention has the above-described configuration. As shown in FIG. 1, the high-temperature atmosphere gas generator 1 is installed near the tundish 15,
The N ₂ gas discharge path 14 is connected to one opening 15 a of the tundish 15. In this state, first, for example, a coke oven gas (low heating value 19.3 MJ)
/ M ³ -N), the heat of combustion heats the regenerator 5a located in the combustion chamber 2a, and the exhaust gas is sucked by the suction blower 12a and released to the atmosphere.

On the other hand, the N ₂ gas is heated to a high temperature by flowing the N ₂ gas from the N ₂ gas supply path 13 to the heat storage body 5b which has been heated in advance in the heat storage chamber 2b. Then, the N ₂ gas heated to a high temperature is blown into the tundish 15 via the N ₂ gas discharge path 14.

Thereafter, the actuator 7 is driven to rotate the rotating shaft 6 by 180 °. This rotation causes the combustion chamber 2
The heat storage element 5a located at a is located in the heat storage chamber 2b, and the heat storage element 5b located at the heat storage chamber 2b is located in the combustion chamber 2a. In this state, the operation described above is performed. By repeating the above operation at a pitch of, for example, 30 seconds to 5 minutes, it becomes possible to continuously generate a high-temperature atmosphere gas.

Incidentally, in the high-temperature atmosphere gas generating apparatus 1 of the present invention described above, the coke oven gas was supplied at 120 m ³ −
When the N ₂ gas is burned at N / h and the air ratio is 1.2, the switching time is 30 seconds, and the N ₂ gas is supplied at 1050 m ³ -N / h, the conventional apparatus is used in the N ₂ gas discharge path 14. N ₂ gas heated to 1100 ° C., which is the same as in the case, could be continuously obtained.

In this embodiment, the heat storage elements 5a and 5b are rotated around the rotation shaft 6, but it is needless to say that the heat storage elements 5a and 5b may be circulated around a portion having a certain area.

In this embodiment, the tundish is preheated with N ₂ gas. However, it goes without saying that the atmosphere gas used is not limited to N ₂ gas.

[0025]

As described above, according to the high-temperature atmosphere gas generating apparatus of the present invention, at least two or more divided heat storage bodies are rotated or circulated around the axis thereof, and one of the heat storage bodies in this rotation or circulation process is rotated. In the combustion chamber where the heat storage material exists, the heat storage material existing in the combustion chamber is heated by the high-temperature gas burned by the burner, and in the same heat storage room where the other heat storage material exists, the heat storage material heated in the combustion chamber is reduced. Since the operation of heating by passing the atmospheric gas is alternately switched, the high-temperature atmospheric gas can be continuously generated.

In the high-temperature atmosphere gas generating apparatus according to the present invention, the above-described structure enables a high-temperature atmosphere gas to be continuously generated by one burner. The fuel switching valve connected to the burner, the combustion air switching valve, the exhaust switching valve, the non-oxidizing atmosphere gas switching valve, and the piping attached to each switching valve,
A control circuit for opening and closing each switching valve becomes unnecessary.

Further, in the high-temperature atmosphere gas generating apparatus of the present invention, since the exhaust of the atmosphere gas in the tundish is not sucked by the exhaust gas blower, there is no fear that the atmosphere is sucked into the tundish from the opening of the tundish as in the conventional apparatus. Absent. Therefore, in the combustion air supply path, the primary side of the orifice is opened, and the combustion air can be sucked from the atmosphere by the suction force of the suction blower provided in the combustion exhaust gas discharge path, so that the combustion air blower is also omitted. be able to.

That is, in the high-temperature atmosphere gas generating apparatus of the present invention, the same high-temperature atmosphere gas as that of the conventional apparatus can be obtained, and at the same time, the number of components of the apparatus can be greatly reduced. In addition to this, it is possible to reduce the size of the apparatus compared to the conventional apparatus, and to install the apparatus at a tundish standby position on a cast floor with a small installation space.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of the entire high-temperature atmosphere gas generator of the present invention.

FIGS. 2A and 2B are schematic structural views of a high-temperature atmosphere gas generating apparatus main body of the present invention, wherein FIG. 2A is a longitudinal sectional view, and FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 High-temperature atmosphere gas generator 2a Combustion chamber 2b Heat storage chamber 5a Heat storage 5b Heat storage 6 Rotary shaft 7 Actuator 8 Burner 9 Fuel supply path 10 Combustion air supply path 12 Combustion exhaust gas discharge path 13 N ₂ gas supply path 14 N ₂ Gas discharge route

Continued on the front page F-term (reference) 4E014 AA02 4K056 AA14 DA27 DA32 4K063 AA04 AA05 AA08 AA15 BA02 CA03 DA07 DA14 DA26

Claims (1)

[Claims] 1. A heat storage element divided into at least two or more parts, a mechanism for rotating or circulating the heat storage element around its axis, and a heat storage element disposed in a combustion chamber in which one of the heat storage elements in the rotation or circulation process exists. A burner, a supply path of fuel and combustion air to the burner, a discharge path of combustion exhaust gas, and a supply path and discharge path of a reducing atmosphere gas communicated with a heat storage chamber in which the other heat storage body is also provided. In the chamber, the regenerator present in the combustion chamber is heated by the high-temperature gas burned by the burner, and in the regenerator, the operation of passing the reducing atmosphere gas to the regenerator heated in the combustion chamber and heating is alternately switched, A high-temperature atmosphere gas generator characterized in that a high-temperature atmosphere gas is continuously generated.