阅读说明：本技术 用于转底炉炉顶炉壁的热交换管助燃热风自给方法及装置 (Method and device for self-supplying combustion-supporting hot air of heat exchange tube for furnace top and wall of rotary hearth furnace ) 是由 滕秋明 刘晓轩 刘安治 丁雪良 曹志成 吴佩佩 姜海龙 于 2021-09-13 设计创作，主要内容包括：本发明公开了一种用于转底炉的炉顶炉壁热交换管助燃热风自给方法及装置,在转底炉的炉顶和炉壁的耐火材料中安装热风管,利用所述转底炉内高温烟气的热量将所述热风管内空气进行加热；再利用加压机构将加热后的所述热风管内空气传输至所述转底炉的内外环上的烧嘴。本发明以吸收转底炉炉顶、炉壁处的高温烟气热量,实现助燃热风自给的目的。(The invention discloses a self-supply method and a device for combustion-supporting hot air of a furnace top and wall heat exchange tube of a rotary hearth furnace, wherein hot air tubes are arranged in refractory materials of the furnace top and the furnace wall of the rotary hearth furnace, and the air in the hot air tubes is heated by utilizing the heat of high-temperature flue gas in the rotary hearth furnace; and then, conveying the heated air in the hot blast pipe to burners on the inner ring and the outer ring of the rotary hearth furnace by using a pressurizing mechanism. The invention realizes the purpose of self-supply of combustion-supporting hot air by absorbing the heat of high-temperature flue gas at the top and wall of the rotary hearth furnace.)

1. A combustion-supporting hot air self-supply method for a furnace top and wall heat exchange tube of a rotary hearth furnace is characterized in that:

installing hot air pipes in refractory materials of the top and the wall of a rotary hearth furnace, and heating air in the hot air pipes by using the heat of high-temperature flue gas in the rotary hearth furnace;

and then, conveying the heated air in the hot blast pipe to burners on the inner ring and the outer ring of the rotary hearth furnace by using a pressurizing mechanism.

2. The method for self-supplying combustion-supporting hot blast of the furnace-top wall heat exchange tube of the rotary hearth furnace as set forth in claim 1, wherein: the hot-blast main is equipped with many, all sets up to the ring form.

3. The method for self-supplying combustion-supporting hot blast of the furnace-top wall heat exchange tube of the rotary hearth furnace as set forth in claim 2, wherein: the hot air pipe is embedded in the refractory material.

4. The method for self-supplying combustion-supporting hot blast of the furnace-top wall heat exchange tube of the rotary hearth furnace as set forth in claim 3, wherein: any two adjacent hot air pipes are communicated.

5. The method for self-supplying combustion-supporting hot blast of the furnace-top wall heat exchange tube of the rotary hearth furnace as set forth in claim 1, wherein: the pressurizing mechanism comprises an air box and a variable frequency fan;

the air box is arranged on one side of a discharge area of the rotary hearth furnace and is communicated with the hot air pipe;

and the variable frequency fan is arranged on the air box and used for pressurizing air in the hot air pipe.

6. A combustion-supporting hot air self-supply device for a heat exchange tube of a furnace top and a furnace wall of a rotary hearth furnace is characterized in that: comprises a hot air pipe and a pressurizing mechanism;

the hot air pipe is arranged in the refractory materials of the furnace top and the furnace wall of the rotary hearth furnace;

the pressurizing mechanism is arranged on one side of the discharging area of the rotary hearth furnace and communicated with the hot air pipe.

7. The self-supplying apparatus of combustion supporting hot blast for the heat exchanging tubes of the furnace top wall of the rotary hearth furnace as set forth in claim 6, wherein: the hot-blast main is equipped with more than two, all sets up to the ring form.

8. The self-supplying apparatus of combustion supporting hot blast for the heat exchanging tubes of the furnace top wall of the rotary hearth furnace as set forth in claim 7, wherein: the hot air pipe is embedded in the refractory material.

9. The self-supplying apparatus of combustion supporting hot blast for the heat exchanging tubes of the furnace top wall of the rotary hearth furnace as set forth in claim 8, wherein: any two adjacent hot air pipes are communicated.

10. The self-supplying apparatus of combustion supporting hot blast for the heat exchanging tubes of the furnace top wall of the rotary hearth furnace as set forth in claim 6, wherein: the pressurizing mechanism comprises an air box and a variable frequency fan;

the air box is arranged on one side of a discharge area of the rotary hearth furnace and is communicated with the hot air pipe;

and installing the variable frequency fan on the air box.

Technical Field

The invention relates to metallurgical thermal technology, in particular to a method and a device for self-supplying combustion-supporting hot air for a furnace top wall heat exchange tube of a rotary hearth furnace.

Background

The total dust amount of steel enterprises in China is generally 8% -12% of the steel output, and with the increase of environmental protection of various large steel plants, the direct reduction process of the rotary hearth furnace is widely applied to the aspect of treating zinc-containing metallurgical dust.

Taking a rotary hearth furnace with 25 ten thousand tons of metallurgical dust and mud treated in a certain steel plant in one year as an example, carbon-distributed pellets in the rotary hearth furnace are used as raw materials, the dried pellets are uniformly distributed on an annular hearth of the rotary hearth furnace, and sequentially pass through a heating zone, a first reduction zone, a second reduction zone, a third reduction zone and a fourth reduction zone in the furnace through a furnace bottom driving device, the reduction of iron oxide and zinc oxide is completed in a high-temperature environment of about 1250 ℃, zinc volatilizes into flue gas and is oxidized into zinc oxide dust to be recovered by a dust remover, and the reduced metallized pellets are discharged from a discharge zone of the rotary hearth furnace through a high-temperature spiral discharging machine. However, the existing rotary hearth furnace process has the following defects:

1) the heat loss between the hot blast stove and the rotary hearth furnace. The high-temperature environment in the rotary hearth furnace needs the hot blast stove to provide combustion-supporting hot air, but the hot blast stove and the rotary hearth furnace are independent equipment units, so that the problems of long pipeline, high energy consumption, large heat loss and the like exist in the production process, and the environmental protection property and the production cost of the rotary hearth furnace process are not facilitated;

2) the internal thermal efficiency of the rotary hearth furnace is utilized to a low degree. The high-temperature flue gas generated by a combustion system of the rotary hearth furnace mainly conducts radiation heat transfer with furnace materials, the heat transfer efficiency is low, a large amount of high-temperature flue gas is concentrated on the top of the rotary hearth furnace under the condition of micro negative pressure and is finally discharged through a flue near a feeding area, the heat utilization efficiency of the rotary hearth furnace is low, and generally, the flue gas of the rotary hearth furnace takes away more than 40% of input heat. In the current various rotary hearth furnace processes, the recovery rate of high-temperature flue gas is only 40% after the high-temperature flue gas passes through recovery equipment such as a waste heat boiler and the like.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a method and a device for self-supplying combustion-supporting hot air for a heat exchange tube at the furnace top and the furnace wall of a rotary hearth furnace, so as to absorb the heat of high-temperature flue gas at the furnace top and the furnace wall of the rotary hearth furnace and realize the self-supplying combustion-supporting hot air.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a method for self-supplying combustion-supporting hot air for a heat exchange tube on a furnace top wall of a rotary hearth furnace, which comprises the following steps:

installing hot air pipes in refractory materials of the top and the wall of a rotary hearth furnace, and heating air in the hot air pipes by using the heat of high-temperature flue gas in the rotary hearth furnace;

and then, conveying the heated air in the hot blast pipe to burners on the inner ring and the outer ring of the rotary hearth furnace by using a pressurizing mechanism.

Preferably, the hot air pipes are provided with a plurality of circular rings.

Preferably, the hot blast pipe is embedded in the refractory material.

Preferably, any two adjacent hot air pipes are communicated.

Preferably, the pressurizing mechanism comprises an air box and a variable frequency fan;

the air box is arranged on one side of a discharge area of the rotary hearth furnace and is communicated with the hot air pipe;

and the variable frequency fan is arranged on the air box and used for pressurizing air in the hot air pipe.

The invention provides a combustion-supporting hot air self-supply device for a furnace top and wall heat exchange tube of a rotary hearth furnace, which comprises a hot air tube and a pressurizing mechanism, wherein the hot air tube is connected with the pressurizing mechanism;

the hot air pipe is arranged in the refractory materials of the furnace top and the furnace wall of the rotary hearth furnace;

the pressurizing mechanism is arranged on one side of the discharging area of the rotary hearth furnace and communicated with the hot air pipe.

Preferably, more than two hot air pipes are arranged and are all arranged in a circular ring shape.

Preferably, the hot blast pipe is embedded in the refractory material.

Preferably, any two adjacent hot air pipes are communicated.

Preferably, the pressurizing mechanism comprises an air box and a variable frequency fan;

the air box is arranged on one side of a discharge area of the rotary hearth furnace and is communicated with the hot air pipe;

and installing the variable frequency fan on the air box.

The invention provides a method and a device for self-supplying combustion-supporting hot air for a heat exchange tube on the wall of a furnace top of a rotary hearth furnace, which have the following beneficial effects:

1) the method is designed for the rotary hearth furnace, and is compatible and matched with related processes and equipment of the rotary hearth furnace;

2) the self-supply of combustion-supporting hot air required by the rotary hearth furnace is completed by absorbing the heat of the high-temperature flue gas;

3) the hot air supply of the hot air furnace to the rotary hearth furnace is omitted, and the problems of long pipeline, high energy consumption, large heat loss and the like between the hot air furnace and the rotary hearth furnace are avoided;

4) effectively reduces the heat load of subsequent flue gas equipment such as a waste heat boiler and the like, and avoids the phenomenon of cloth bag burnthrough during cloth bag dust removal.

Drawings

FIG. 1 is a schematic view of the on-site layout of a combustion-supporting hot blast self-supply device for the heat exchange tubes of the furnace roof and wall of the furnace of the present invention;

fig. 2 is a schematic view of direction a in fig. 1.

Detailed Description

In order to better understand the technical solutions of the present invention, the following further describes the technical solutions of the present invention with reference to the accompanying drawings and examples.

Referring to fig. 1 and 2, in a first aspect, the present invention provides a method for self-supplying combustion-supporting hot air to a heat exchange tube of a furnace top wall of a rotary hearth furnace, comprising:

the hot air pipe 2 is arranged in the refractory material 5 at the top and the refractory material 1 at the wall of the rotary hearth furnace 100, the air in the hot air pipe 2 is heated by the heat of high-temperature flue gas in the rotary hearth furnace 100, and then the heated air in the hot air pipe 2 is transmitted to the burners on the inner ring and the outer ring of the rotary hearth furnace 100 by the pressurizing mechanism, so that the self-supply of combustion-supporting hot air of the rotary hearth furnace 100 is realized.

The hot air pipes 2 are arranged in a plurality of annular shapes, and the hot air pipes 2 are embedded in the refractory material 5 at the top of the furnace and the refractory material 1 at the wall of the furnace.

As shown in the position B in fig. 1, after the hot blast pipes 1 are installed in the refractory 5 installed in the furnace top and the refractory 1 installed in the furnace wall, any two adjacent hot blast pipes 1 are passed through on the side close to the charging zone 101 of the rotary hearth furnace 100.

The pressurizing mechanism comprises an air box 3 and a variable frequency fan 4.

An air box 3 is installed on one side of the discharge area 102 of the rotary hearth furnace 100 and is communicated with the hot air duct 2, and a variable frequency fan 4 is installed on the air box 3 for pressurizing air in the hot air duct 2.

The rotary hearth furnace combustion system mainly adopts a radiation heat transfer mode between high-temperature flue gas generated by the rotary hearth furnace combustion system and furnace burden, the heat transfer efficiency is low, a large amount of high-temperature flue gas is concentrated in the top area in the furnace under the condition of micro negative pressure, and finally the high-temperature flue gas is discharged through a flue near a feeding area, so that the heat utilization efficiency of the rotary hearth furnace is low, and the self-supply of combustion-supporting hot air can be completed by recovering the heat of the high-temperature flue gas. The hot air pipe 2 is arranged in the refractory material 1 at the top and the wall of the rotary hearth furnace 100, the air in the hot air pipe 2 is heated by the heat of high-temperature flue gas in the furnace, and then the heated air is pressurized and conveyed to the burners at the inner ring and the outer ring of the rotary hearth furnace 100 through the variable frequency fan 4, so that the self-feeding of combustion-supporting hot air of the rotary hearth furnace is realized. In addition, due to the reduction of the temperature of the high-temperature flue gas, the heat load of subsequent equipment such as a waste heat boiler and cloth bag dust removal can be effectively reduced.

The invention provides a combustion-supporting hot air self-supply device for a furnace top and furnace wall heat exchange tube of a rotary hearth furnace, which comprises a hot air tube 2 and a pressurizing mechanism.

The hot blast pipe 2 is provided in the refractory 5 on the top and the refractory 1 on the wall of the rotary hearth furnace 100.

The pressurizing mechanism is arranged on one side of the discharging area 102 of the rotary hearth furnace 100 and is communicated with the hot blast pipe 2.

More than two hot air pipes 2 are arranged and are all in a circular ring shape.

The hot blast pipes 2 are embedded in the refractory 5 of the top and the refractory 1 of the wall of the rotary hearth furnace 100.

As shown in fig. 1 at position B, after the hot blast pipes 1 are installed in the refractory 5 installed in the furnace top and the refractory 1 installed in the furnace wall, any two adjacent hot blast pipes 1 are passed through on the side close to the charging zone 101 of the rotary hearth furnace 100, and the air in the interior is made to flow.

The pressurizing mechanism comprises an air box 3 and a variable frequency fan 4.

An air box 3 is installed on one side of the discharge area 102 of the rotary hearth furnace 100 and is communicated with the hot air duct 2, and a variable frequency fan 4 is installed on the air box 3 for pressurizing air in the hot air duct 2.

The method and the device for self-supplying the combustion-supporting hot air of the heat exchange tube on the furnace top and the furnace wall of the rotary hearth furnace complete the self-supply of the combustion-supporting hot air of the rotary hearth furnace by recovering the heat of the high-temperature flue gas in the rotary hearth furnace, not only get rid of the problems of long pipeline, high energy consumption, large heat loss and the like caused by the fact that the combustion-supporting hot air is supplied by a hot blast stove in the traditional process, but also effectively reduce the heat load of subsequent flue gas equipment such as a waste heat boiler and the like, avoid the phenomenon of burning through a cloth bag during cloth bag dust removal, and have better economic benefit and environmental protection benefit. In addition, the following problems are also solved:

1) the defects of high energy consumption, long pipeline and low heat efficiency of the current front rotary hearth furnace process equipment are overcome;

2) the heat of the high-temperature flue gas can be effectively utilized to complete the self-supply of the combustion-supporting hot air in the rotary hearth furnace;

3) the heat load of subsequent flue gas equipment such as a waste heat boiler and the like can be effectively reduced, and the phenomenon of cloth bag burnthrough during cloth bag dust removal is avoided.

It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above described embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.