JPS6248794B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ignition device for a sintering machine, and in particular to an ignition device that saves fuel and downsizes the device by employing a strip-shaped flame burner that creates continuous flame in the width direction of the pallet. be.

Generally, the ignition device of a sintering machine uses a burner to ignite the upper surface of the sintering raw material layer charged and deposited on a pallet using heavy oil, coke oven gas, or a mixed gas of coke oven gas and blast furnace gas. This is used to combust the coke in the sintering raw material through the joint action of the combustion flame and high-temperature hot air obtained at that time.

An example of a conventional sintering machine used for this purpose is the one shown in FIG. In the figure, 1 is a pallet, 2 is a wind box, and 3 is an ignition device, which includes an ignition furnace 3a and a burner 3b. Further, numerals 4 and 5 indicate a bedding hopper and a raw material hopper, respectively.

FIG. 2 is an enlarged cross-sectional view of the conventional ignition device 3. Here, a burner row consisting of a plurality of burners 3b aligned in the width direction of the pallet 1 is shown in the direction of movement of the pallet 1. The coke in the raw material 6 in the pallet 1 is ignited and burned by each burner 3b and by suctioning and exhausting exhaust gas through the wind box 2.

However, in such a conventional technique, as is clear from FIG.
Since there is a clear difference in ignition strength between the position immediately below the ignition strength and the intermediate position between them, there was a problem of uneven firing. When adjusting the combustion rate of the fuel, there was a problem that the energy used increased and the fuel consumption rate was poor. Moreover, since each burner 3b has a different ignition strength, it is extremely difficult to obtain a uniform ignition strength distribution in the width direction of the pallet 1.

In addition, in the conventional ignition device, an ignition furnace 3a is used to preheat the sintering raw material or to retain heat after ignition.
The furnace capacity was increased and hot air was blown into the sintered raw material before and after the ignition point, but this method has not been effective in improving quality or reducing fuel consumption and is on the verge of being phased out. Moreover, in the conventional ignition furnace 3a, the height of the furnace was set to an average height of 1500 mm for the purpose of not only burning the burner flame but also coke combustion by combustion high-temperature gas. This tends to increase energy loss as the distance between them increases, and the natural dissipation of heat due to larger equipment also adds to the energy loss.

In response to this, an ignition device has recently been proposed, disclosed in Japanese Patent Laid-Open No. 57-37685, which has a single mixing combustion chamber and a slit-shaped combustion gas discharge port. This device had the following drawbacks because what was blown out from the slit-shaped outlet was not a flame but a type of high-temperature exhaust gas.

(1) Since the mixing chamber becomes red-hot, the burner chip that serves as the combustion gas discharge port is easily deformed, making it difficult to obtain a stable frame, making it difficult to ignite uniformly in the width direction of the pallet.

(2) In order to prevent the slit-shaped burner chips from deforming, special materials are required, and the structure becomes complicated, resulting in high equipment costs.

(3) It is difficult to achieve complete combustion in the above mixing chamber;
Gas is likely to be discharged and cause ignition failure.

(4) Furthermore, like the existing equipment, energy loss cannot be avoided because the ignition furnace is large, and the furnace structure is large and requires a large support strength, which increases equipment costs.

An object of the present invention is to overcome the drawbacks of the above-mentioned ignition furnace and conventional ignition device having a slit-shaped combustion gas discharge port, thereby achieving downsizing of equipment and simplification of repair, thereby reducing equipment costs. The object of the present invention is to provide a device which is advantageous in reducing energy consumption as well as saving energy.

To achieve this object, the ignition device of the present invention has a fuel gas pipe and a combustion air pipe arranged in the width direction of the pallet of the sintering machine, and a fuel gas burner passage from the fuel gas pipe to the pallet. At the same time, an air burner passage is provided in a belt shape projecting from the combustion air pipe toward the pallet, and the air burner passage sandwiches the fuel gas burner passage from the front and back in the pallet moving direction. The burner body is constituted by: a gas nozzle passage communicating with the fuel gas burner passage; an air nozzle passage communicating with the air burner passage; and these gas nozzle passages and air nozzle passages intersecting with each other. By providing a gas nozzle hole and an air nozzle hole facing in the direction, a burner tip that can be attached and detached from the burner body is constructed.Furthermore, a small burner hood is provided that covers only the combustion atmosphere below the burner tip. Both the air nozzle holes and the gas nozzle holes are configured by a combination of round holes and slit holes facing in the width direction of the pallet, and the unit opening area of the gas nozzle hole and the air nozzle hole in the side end portion of the pallet is equal to that in the center portion of the pallet. It is made larger than the unit opening area.

Note that the term "round hole" here has the meaning of clarifying the difference from a slit hole, and includes not only elliptical and oval holes but also polygonal holes.

According to the ignition device of the present invention, fuel gas and combustion air are ejected from the gas nozzle hole and the air nozzle hole in mutually intersecting directions, thereby producing a uniform strip in the width direction of the pallet with low energy consumption. A short flame is provided and a miniaturization of the burner hood and thus of the device itself is achieved. With this miniaturization of the burner hood, the connecting portion of the removable burner tip to the burner body is exposed to the outside of the burner hood, making it extremely easy to replace the burner tip. Furthermore, the unit opening area of the gas nozzle hole and air nozzle hole, which are a combination of a round hole and a slit hole, has a large amount of heat dissipation to the outside and a large amount of ventilation into the raw material.
In particular, by making the side edges of the pallet larger than other areas to increase the ignition strength there, it eliminates the effects of uneven heat radiation and ventilation, resulting in uniform sintering in the width direction of the pallet. be able to.

The present invention will be explained below based on the drawings.

FIG. 4 shows a preferred example of the ignition device of the present invention.

In the figure, 11 and 12 indicate a fuel gas pipe and a combustion air pipe which are arranged concentrically with each other, and 13
14 indicates a fuel gas supply pipe, and 14 indicates an air supply pipe.

Each of these pipes extends in the width direction of the pallet 1, and includes a fuel gas pipe 11 and a combustion air pipe 12.
are connected to the fuel gas supply pipe 13 and the air supply pipe 14 by the short pipes 15 and 16 at multiple locations in the axial direction.
are connected to each separately. Here, coke oven gas and other gases are contained in the fuel gas pipe 11 forming the central flow path, and combustion air pipe 1 forming the annular flow path.
Air circulates within each of the two.

Preferably, rectifying plates 17 and 18 that can be inserted and removed in the axial direction are arranged in the fuel gas pipe 11 and the combustion air pipe 12, respectively, and the rectifying plates 17 and 18 are provided with a rectifying plate 17 and 18 that can be inserted and removed in the axial direction of the pipes 11 and 12, respectively. A large number of holes 19, 20 are provided to provide an even gas flow distribution.

Further, the fuel gas pipe 11 is provided with a belt-shaped fuel gas burner passage 21 that projects in the direction of the pallet 1 and extends in the width direction of the pallet 1, and the combustion air pipe 12 is provided with a belt-shaped fuel gas burner passage 21 that also projects in the direction of the pallet 1. ,
Belt-shaped air burner passages 22a and 22b are provided which extend in the width direction of the pallet 1 and sandwich the fuel gas burner passage 21 from the front and back in the pallet moving direction, and at the tips of these air burner passages 22a and 22b, external The burner body Bb is constituted by providing the facing flanges 23a and 23b.

A burner chip Bt, which will be described in detail below, is connected to this burner body Bb with a bolt 24. This burner chip Bt is the burner passage 2 for fuel gas.
1 and air burner passages 22a, 22b, respectively, and gas nozzle holes 27a, 27b and air nozzle holes provided at the tips of these passages 25, 26a, 26b, respectively. It has nozzle holes 28a and 28b. And this burner tip Bt is further connected to the air nozzle passage 2.
Flanges 29a, 29 provided at the upper ends of 6a, 26b and aligned with outward flanges 23a, 23b
have b.

The gas nozzle holes 27a, 27b in the burner chip Bt are oriented outwardly, and the air nozzle holes 28a, 28b are opened inward in correspondence with the gas nozzle holes 27a, 27b, respectively. and 28a, 2
8b are oriented in directions that intersect with each other, preferably at orthogonal angles or at near-perpendicular angles. Here, the gas nozzle holes 27a, 27b and the air nozzle hole 28
As is clear from FIGS. 5 and 6, holes a and 28b are formed by combining a plurality of round holes 30 and slit holes 31, and each hole 27a, 27b and 28a,
The unit opening area of 28b is made larger at the side end portions of the pallet 1 than at other portions.

This change in the unit opening area is due to the fact that the amount of burner heat is dissipated to the outside in a particularly large amount in the areas corresponding to both ends of the pallet 1, and in the area near the sidewalls of the pallet 1, the exhaust gas passing through the wind box 2 is sucked and exhausted. This is based on the fact that due to the effect of the smooth sidewall surface, the amount of ventilation into the raw material is greater than in other parts, and the combustion flame and high-temperature hot air have a strong tendency to be cooled by the suction air. By increasing the ignition strength in the pallet, these effects can be corrected and sintering can be performed evenly in the width direction of the pallet.

In addition, here we use the burner tip Bt as the burner body.
Since it is detachable from Bb, the unit opening area can be easily selected by changing the burner tip Bt. In addition, in the illustrated example, the round holes 30 are placed at the side edges of the pallet 1, and the slit holes 31 are placed at the center of the pallet 1, but this arrangement may be used as long as the required unit opening area can be secured. The reverse is also possible.

According to the gas nozzle holes 27a, 27b and the air nozzle holes 28a, 28b described above, the fuel gas and air are injected so as to cross each other, and are mixed and combusted at the intersection, so that the pallet 1 is A strip-shaped frame with substantially uniform ignition strength across the width can be obtained, and the flame has a short flame. In particular, in order to provide a belt-shaped frame with uniform ignition strength, the above-mentioned slit holes 31 are particularly effective, and each hole 27
By selecting the unit opening areas of a, 27b and 28a, 28b as described above, it is possible to provide high ignition strength at the pallet side end portion, as shown in FIG. Uniform combustion as shown in FIG. 8 is produced.

On the other hand, the short flame of the flame allows the surface of the raw material 6 on the pallet 1 to approach the burner chips Bt, which covers the combustion atmosphere and prevents heat dissipation and prevents outside air from entering. The burner hood 32 can be made smaller,
This results in a further reduction in energy loss and lower equipment costs.

Furthermore, the effect of making the burner hood 32 smaller produces the following synergistic effect in conjunction with the use of the removable burner tip Bt. That is,
By employing the burner tips Bt of the present invention, ignition can be performed uniformly in the width direction of the pallet and is advantageous in terms of thermoeconomics, so that the hood 32 only needs to cover the burner tips Bt. However, although this is a phenomenon often seen in conventional burners, the miniaturization of the burner hood 32 in particular
This has the disadvantage of causing overheating and thermal deformation. To deal with this, methods such as changing the material of the burner tip Bt to heat-resistant steel are taken, but it is desirable to make it possible to easily replace only the burner tip Bt.In order to meet these demands, the present invention has developed a tip that can be replaced easily. This makes it removable from the burner body. Furthermore, in order to facilitate replacement, a burner hood is provided below the removable part of the burner chip to protect the removable part from high heat and prevent thermal deformation of the removable part.

Although this invention has been explained above based on illustrated examples,
When the burner body Bb and the burner tip Bt are made tiltable or movable up and down, their positions can be changed as appropriate depending on the sintering operation.

As described above, according to the present invention, the burner flame becomes a short flame band that is uniform in the width direction of the pallet.
The ignition strength is made uniform, the hood is made smaller, and energy loss is greatly reduced. For example, according to experiments conducted by the present inventors, the conventional fuel consumption rate was
What was 15000Kcal/t-Sinter,
9000Kcal/t-Sinter (sinter production 5000t/D,
3.9Nm ³ /t, A/G = 2.2, mixed gas calories =
2300Kcal/Nm ³ ).

Further, according to the present invention, since the burner tip can be easily replaced, the life of the ignition device can be extended. In addition, construction and maintenance costs can be saved because the entire equipment can be downsized and parts can be replaced.

Furthermore, uniform ignition can be achieved in the width direction of the pallet (see Figures 7 and 8), eliminating uneven burning and significantly improving the yield of sintered products.

In addition, another effect brought about by the burner chip of the present invention is that by increasing the unit opening area of each nozzle hole in consideration of the ventilation and heat dissipation of the pallet sidewall section, it is possible to improve the impact on the raw material. The purpose is to provide uniform heat transfer and advantageously eliminate uneven heating particularly in that area.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of the sintering machine, Fig. 2 is an enlarged sectional view of a conventional ignition device, Fig. 3 is a distribution graph of the ignition strength in the pallet width direction by the conventional ignition device, and Fig. 4
5 is a partially cutaway bottom view of the ignition device of the present invention, and FIG. 6 is an enlarged view of part A in FIG. 5 showing the nozzle hole of the burner tip. FIG. 7 is a distribution graph of the ignition strength in the width direction of the pallet by the ignition device of the present invention, and FIG. 8 is a front view of the sintering machine pallet and the ignition device of the present invention in cross section. Bb...Burner body, Bt...Burner chip, 1...Pallet, 11...Fuel gas pipe, 12...Combustion air pipe, 21...Fuel gas burner passage, 22a, 22
b...Air burner passage, 23a, 23b, 29
a, 29b...flange, 24...bolt, 25...gas nozzle passage, 26a, 26b...air nozzle passage, 27a, 27b...gas nozzle hole, 28a, 2
8b...Air nozzle hole, 30...Round hole, 31...Slit hole.

Claims (1)

[Claims] 1. A fuel gas pipe 11 and a combustion air pipe 12 arranged in the width direction of the pallet of the sintering machine, and a fuel gas pipe 11 extending in a band shape from the fuel gas pipe 11 toward the pallet 1. burner passage 21 and combustion air pipe 1
Air burner passages 22a, 22, which are also belt-shaped, protrude from the pallet 2 toward the pallet 1 and sandwich the fuel gas burner passage 21 from the front and back in the pallet moving direction.
a burner body Bb including a burner body Bb, a gas nozzle passage 25 communicating with the fuel gas burner passage 21, and the air burner passage 22.
Air nozzle passages 26a and 26b communicating with air nozzle passages 26a and 22b, and these gas nozzle passages 25
and gas nozzle holes 27a, 27b and air nozzle holes 28a, 2 provided in the air nozzle passages 26a, 26b and facing in mutually intersecting directions.
8b, a burner tip Bt that is removable from the burner body Bb, and a small burner hood 32 that covers only the combustion atmosphere below the burner tip Bt, the gas nozzle holes 27a, 27b and the air nozzle holes 28a, 28b are both constituted by a combination of a round hole 30 and a slit hole 31 facing in the pallet width direction, and the gas nozzle holes 27a, 27b and the air nozzle hole 2 at the side end portion of the pallet 1
An ignition device for a sintering machine in which the unit opening area of the pallets 8a and 28b is larger than the unit opening area of the pallets 8a and 28b in the central portion of the pallet 1.