JP7155926B2 - sintering machine - Google Patents

Description

The present disclosure relates to sintering machines.

In the ironmaking process, iron ores and coke are charged into a blast furnace and chemically reacted at high temperatures to produce pig iron. Sintered ore obtained by agglomerating fine ore is conventionally used as the iron ore to be charged into the blast furnace, since the blast furnace is clogged if the fine ore is charged into the blast furnace as it is. The sintered ore is produced by granulating a blended material composed of ore fines, limestone, coke fines, etc. to produce a sintering raw material, and then sintering the sintering raw material.

A Dwight Lloyd (DL) type sintering machine is widely used for the production of sintered ore. A DL type sintering machine includes a plurality of pallet trucks, an ignition furnace, and a wind box group. A plurality of pallet trucks travel from an ore supply section to which sintering raw materials are supplied toward an ore discharge section to which sintered ore is discharged. The ignition furnace ignites the surface of the raw material for sintering loaded onto the pallet truck. The windboxes are arranged below the pallet trucks that run from the feed station to the mine discharge station. The wind box group sucks air above the pallet trucks to promote combustion of coke in the sintering material.

Patent Literature 1 discloses a method for producing sintered ore using a DL sintering machine. In the manufacturing method of Patent Document 1, after the raw material for sintering is ignited, a small hole reaching the combustion zone of the sintered layer is provided by a spike roller. The small holes are formed between the lower surface of the combustion zone and the surface of the sintered layer until it reaches 30% of the height of the sintered layer, and are scattered in the width direction of the sintered layer. According to Patent Document 1, the small holes disperse and absorb tension caused by quenching, preventing the occurrence of large cracks, and equivalently reducing the thickness of the sintered layer to improve air permeability. be.

Patent Literatures 2 and 3 disclose a DL type sintering machine for accurately measuring the layer thickness of a charged layer of sintering raw material and uniformizing the ventilation state. In the sintering machines of Patent Literatures 2 and 3, the thickness of the charging layer is detected in the width direction of the pallet truck by the layer thickness detection unit, and the increased aeration required area (consolidation area) is extracted. If there is a consolidation area in the charging layer, the ventilation rod is inserted into the consolidation area to a predetermined depth to ensure the ventilation of the consolidation area.

In the sintered ore production method of Patent Document 4, portions with a high porosity are formed at both ends in the width direction of the charging layer of the sintering raw material. In areas with high porosity, before the charging layer enters the ignition furnace, plate-like ventilation slits or rod-like ventilation rods are inserted into the charging layer in advance and fixed to prevent the pallet truck from traveling. formed with A gaseous fuel is introduced into the portion with a high porosity in order to ensure a sufficient high-temperature holding time required for sintering.

Patent Document 5 discloses a method of charging raw materials for sintering into a sintering machine. In Patent Document 5, a plurality of slit-like grooves arranged in the width direction of the pallet truck are formed by a slit-forming rod that is positioned in advance. According to Patent Document 5, by charging coke fine into these slit-shaped grooves, the carbon concentration can be increased without impairing the permeability of the charging layer of the sintering raw material.

JP-A-4-143229 Japanese Patent No. 5458780 JP 2012-046813 A JP 2013-076105 A JP-A-2-301525 Japanese Patent No. 2927217

In Patent Document 1, small holes are formed at the stage when a sintering completion zone begins to be formed after the sintering raw material is ignited. Moreover, the small holes are formed by piercing the sintered layer with a pin protruding from the surface of the spike roller. As a result, the surface of the sintered layer becomes rough and a large amount of return ore is generated.

Here, the return ore is small sintered ore having a particle size of about 5 mm or less (hereinafter also referred to as fine-grained sintered ore). If more than an appropriate amount of fine sintered ore is added to the blast furnace, the air permeability inside the blast furnace will deteriorate, making it easier for gas to drift in the furnace, which can lead to malfunctions in the operating conditions of the blast furnace, such as blow-through inside the furnace. be. For this reason, the amount of fine sintered ore charged into the blast furnace is limited to, for example, 5% or less of the total amount of sintered ore charged into the blast furnace. In order to comply with the restrictions on the amount of fine-grained sintered ore input, the sintered ore is sieved in the sintering plant, and the fine-grained sintered ore is returned to the sintering machine without being sent to the blast furnace, and is re-sintered. It's becoming In general, on the surface of the sintered layer (sintered bed) on the pallet truck, even if the coke in the sintering raw material burns, there is almost no heat accumulation, and the slag components do not sufficiently melt. Therefore, the surface portion of the sintering bed has a low strength, and easily collapses into fine grains due to a slight external force such as a drop impact during transportation, so that return ore is likely to occur. It is desired to improve the strength of the surface portion of the sintering bed and reduce return fines. In a conventional sintering plant, for example, a huge amount of return ore such as 15 to 30% of the sintered ore fired on the sintering bed is generated. If the amount of return fines can be reduced, the sintering output will increase. For this reason, sintering plants are in great need of improving the amount of return ores generated.

In Patent Documents 2 to 5, grooves are formed in the sintering raw material as the pallet truck travels by inserting and fixing rod-shaped bodies or plate-shaped bodies into the sintering raw material. In this case, the sintering raw material particles pushed apart by the bar or plate are considered to receive an upward force from the bar or plate while they are in contact with the bar or plate. However, the particles of this sintering raw material lose their support and fall when separated from the bar or plate. As a result, the inner surface of the groove collapses to generate portions where the density of the particles of the sintering raw material is low, and return fines generated during the sintering operation increase.

An object of the present disclosure is to provide a sintering machine capable of reducing the airflow resistance of the sintered raw material to be fired and suppressing the generation of return fines.

A sintering machine according to the present disclosure includes a pallet truck, an ignition furnace, and a disk. The sintering raw material is loaded into the pallet truck. The pallet truck runs on an endless track. An ignition furnace ignites the sintering raw material on the pallet truck. The disk is arranged upstream of the ignition furnace in the direction of travel of the pallet truck. The disk rotates around the axis of rotation. The rotating shaft extends in the width direction of the endless track. The disc has a perimeter. The outer periphery penetrates into the sintering material on the pallet truck to form a groove. The outer peripheral portion is formed so that the thickness decreases from the inner peripheral side to the outer peripheral side of the disk.

According to the sintering machine according to the present disclosure, it is possible to reduce the airflow resistance of the sintered raw material to be fired, and to suppress the generation of return fines.

FIG. 1 is a side view showing the outline of the sintering machine according to the embodiment. 2 is a front view of a coolant supply device included in the sintering machine shown in FIG. 1. FIG. 3 is a front view of a groove forming device included in the sintering machine shown in FIG. 1; FIG. 4 is an enlarged view of a disk included in the groove forming device shown in FIG. 3. FIG. 5 is a side view of the grooving device shown in FIG. 3; FIG. 6 is a plan view and a side view showing the operating state of the disk shown in FIGS. 3 and 4. FIG. FIG. 7 is a longitudinal sectional view of a sintered layer formed by a conventional sintering machine. 8 is a longitudinal sectional view of a sintered layer formed by the sintering machine shown in FIG. 1. FIG. 9 is a longitudinal sectional view of another sintered layer formed by the sintering machine shown in FIG. 1. FIG.

A sintering machine according to an embodiment includes a pallet truck, an ignition furnace, and a disc. The sintering raw material is loaded into the pallet truck. The pallet truck runs on an endless track. An ignition furnace ignites the sintering raw material on the pallet truck. The disk is arranged upstream of the ignition furnace in the direction of travel of the pallet truck. The disk rotates around the axis of rotation. The rotating shaft extends in the width direction of the endless track. The disc has a perimeter. The outer periphery penetrates into the sintering material on the pallet truck to form a groove. The outer peripheral portion is formed so that the thickness decreases from the inner peripheral side to the outer peripheral side of the disc (first configuration).

In the first configuration, grooves are formed in the raw material for sintering by the outer periphery of the rotating disc. More specifically, the perimeter of the disc begins to penetrate and groove the sintering material on the pallet truck. The raw material for sintering is pushed apart by the outer periphery of the rotating disc. At this time, a downward force acts on the sintering raw material due to the rotation of the disk and the surface shape of the outer peripheral portion whose thickness decreases from the inner peripheral side to the outer peripheral side. Therefore, when the particles of the sintering raw material are separated from the disk, the particles of the sintering raw material are less likely to fall, and grooves having smooth inner surfaces are formed in the sintering raw material.

The outer circumference of the disk completes the groove by spreading the sintering material from the surface of the sintering material to the lowest point. After that, the outer circumference of the disk exits the completed groove as the disk rotates. Here, the outer peripheral portion of the disc is formed so that the thickness decreases from the inner peripheral side to the outer peripheral side, and since the portion with the larger thickness is removed from the groove in order, the portion that is removed is It does not touch the inner surface of already formed grooves. Therefore, the inner surfaces of the grooves formed in the raw material for sintering can be maintained in a smooth state.

As described above, according to the sintering machine according to the first configuration, the grooves are formed in the sintered raw material to be fired, so that the airflow resistance of the sintered raw material can be reduced. In addition, since the inner surface of the groove can be made smooth, low-density portions are less likely to occur in the raw material for sintering, and the generation of return ores can be suppressed.

The outer peripheral portion preferably has a tapered surface when viewed in a cross section taken along a plane passing through the center of the disk and including the rotation axis (second configuration).

According to the second configuration, the sintering raw material can be uniformly pressed by the tapered surface of the outer peripheral portion when viewed in a cross section taken along a plane that passes through the center of the disk and includes the rotation axis. As a result, the inner surface of the groove can be more reliably made smooth, and the generation of return ores can be further suppressed.

The outer peripheral portion is preferably surface-treated to improve wear resistance (third configuration).

According to the third configuration, it is possible to reduce wear of the outer peripheral portion that contacts the raw material for sintering, so that it is possible to extend the life of the disk.

Preferably, the sintering machine further comprises a scraper. The scrapers can be arranged on both sides of the disk along the outer periphery above the sintering raw material on the pallet truck (fourth configuration).

According to the fourth configuration, the sintering raw material adhering to the disc can be removed by the scraper each time the groove is formed. As a result, it is possible to prevent the lumps of the sintered material adhering to the disk from growing. Therefore, it is possible to prevent the shape of the groove formed by the disk from changing, and to maintain the airflow resistance of the raw material for sintering uniformly.

The sintering machine preferably further includes a position adjusting mechanism. The position adjustment mechanism adjusts the position of the disk in the width direction of the endless track (fifth configuration).

According to the fifth configuration, grooves can be formed at desired positions with respect to the raw material for sintering on the pallet truck, taking into consideration variations in airflow resistance and the like.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each figure, the same or corresponding configurations are denoted by the same reference numerals, and the same description will not be repeated.

<Configuration of sintering machine>
FIG. 1 is a side view of a sintering machine 1 according to an embodiment. The sintering machine 1 produces sintered ore by sintering raw materials for sintering. The raw material for sintering is a granular raw material produced by granulating a mixed material composed of fine ore, limestone, coke fine, and the like.

As shown in FIG. 1, the sintering machine 1 includes a sintering machine body 10, a charging device 20, an ignition furnace 30, an exhaust gas circulation device 40, a coolant supply device 50, and a groove forming device 60. Prepare.

[Sintering machine body]
The sintering machine main body 10 sinteres the sintering raw material supplied from the ore supply section 11 while conveying it toward the ore discharge section 12 . The raw material for sintering (sintered ore) after firing is discharged from the ore discharge section 12 . The sintering machine body 10 includes an endless track 13 , a plurality of pallet trucks 14 and a plurality of wind boxes 15 .

(endless track)
The endless track 13 has a driving sprocket wheel 131, a driven sprocket wheel 132, and rails 133,134. The driving sprocket wheel 131 is arranged on the side of the feed section 11 and is rotated by a driving device (not shown). The driven sprocket wheel 132 is arranged on the ore discharge section 12 side. Rails 133 , 134 extend horizontally between driving sprocket wheel 131 and driven sprocket wheel 132 . The rail 134 is arranged below the rail 133 . A curved track may be provided instead of the driven sprocket wheel 132 .

(Pallet cart)
A plurality of pallet trucks 14 are arranged along the endless track 13 and run on the endless track 13 . Each of the pallet trucks 14 circulates on drive sprocket wheels 131 , rails 133 , driven sprocket wheels 132 , and rails 134 by rotationally driving the drive sprocket wheels 131 .

The pallet truck 14 travels on the rails 133 from the ore supply section 11 side to the ore discharge section 12 side. When reaching the driven sprocket wheel 132, the pallet truck 14 turns back by hooking its axle on the teeth of the driven sprocket wheel 132, and travels on the rail 134 from the ore discharging section 12 side to the ore feeding section 11 side. When reaching the drive sprocket wheel 131, the pallet truck 14 turns back by hooking its axle on the teeth of the drive sprocket wheel 131, and travels on the rail 133 again.

The sintering raw material is loaded into the pallet truck 14 . The pallet truck 14 travels on the rail 133 from the ore supply section 11 toward the ore discharge section 12 . While the pallet truck 14 is traveling on the rails 133, the firing of the sintering material proceeds.

Hereinafter, the layer of the sintering raw material on the pallet carriage 14 before firing is called a raw material bed, and the layer of sintering raw material on the pallet carriage 14 after firing is called a sintering bed or a sintering layer. The mid-firing sinter bed includes a sinter completion zone, a combustion and melting zone, and a wet zone. The sintered zone is the top layer of the sintering bed where the sintering material has been burned out and agglomeration is complete. The combustion/melting zone is located below the sintering completion zone. The combustion/melting zone is a layer in which the coke in the sintering raw material is burned and the iron ore of the sintering raw material is partially melted. The wet zone is the bottom layer of the sinter bed and consists only of sintering raw material before combustion.

Further, the route of the pallet truck 14 from the ore discharge section 11 to the ore discharge section 12 on the rails 133 is called the forward route, and the route of the pallet truck 14 from the ore discharge section 12 to the ore discharge section 11 on the rails 134 is called the return route. called. In the forward route, the side of the ore supply section 11 is referred to as upstream, and the side of the ore discharge section 12 is referred to as downstream. The forward path of the present embodiment is provided with a firing zone 16 for advancing firing of the sintering bed and a cooling zone 17 for cooling the sintering bed after passing through the firing zone 16 .

(wind box)
A plurality of wind boxes 15 are provided on the outward route. More specifically, a plurality of wind boxes 15 are arranged along the rails 133 below the rails 133 . The pressure inside each wind box 15 is set to a pressure (negative pressure) lower than the atmospheric pressure. Each wind box 15 sucks the air above the pallet truck 14 traveling on the forward route to ventilate the sintering bed. This cools the sintering completion zone and promotes coke combustion in the combustion/melting zone.

[Charging device]
The charging device 20 charges the raw material for sintering to the pallet truck 14 traveling on the forward route. The charging device 20 is provided above the sintering machine body 10 . More specifically, the charging device 20 is provided above the rail 133 on the side of the ore feeding section 11 .

The charging device 20 includes a bedding hopper 21 and a surge hopper 22 . Bedding hopper 21 supplies bedding ore onto pallet truck 14 . The surge hopper 22 is arranged downstream of the floor hopper 21 in the running direction of the pallet truck 14 . A surge hopper 22 supplies sintering material onto the pallet truck 14 .

[Ignition Furnace]
The ignition furnace 30 is provided on the forward route. More specifically, the ignition furnace 30 is provided above the rail 133 on the side of the ore feeding section 11 . The ignition furnace 30 is arranged downstream of the charging device 20 in the direction of travel of the pallet truck 14 . The ignition furnace 30 ignites the raw material bed on the pallet truck 14 traveling on the forward route.

[Exhaust gas circulation device]
The exhaust gas circulation device 40 circulates and supplies part of the air sucked by the wind box 15 to the sintering bed. The exhaust gas circulation device 40 has an exhaust duct 41 , circulation hoods 42 and 43 , a circulation duct 44 , a boiler 45 and a fan 46 .

Each wind box 15 arranged in the cooling zone 17 is connected to the exhaust duct 41 . A circulation hood 42 is arranged in the baking zone 16 . A circulation hood 43 is arranged in the cooling zone 17 . A circulation duct 44 connects the exhaust duct 41 and the circulation hood 42 of the baking zone 16 via a boiler 45 and a fan 46 . The air (exhaust gas) sucked by the wind box 15 of the cooling zone 17 is supplied into the circulation hood 42 of the baking zone 16 through the exhaust duct 41 and the circulation duct 44 . Although not shown, the exhaust gas from the wind box 15 is also supplied into the circulation hood 43 of the cooling zone 17 via the exhaust duct 41 and the circulation duct 44 .

[Cooling supply device]
The coolant supply device 50 is provided above the sintering machine body 10 . More specifically, the refrigerant supply device 50 is arranged between the circulation hoods 42 and 43 above the rails 133 . A coolant supply device 50 supplies coolant to the sintering bed exposed between the circulation hoods 42 and 43 . Although not particularly limited, for example, water or the like can be used as the coolant.

FIG. 2 is a front view of the coolant supply device 50. FIG. As shown in FIG. 2 , the coolant supply device 50 has a supply pipe 51 and multiple nozzles 52 . The supply pipe 51 extends in the width direction of the pallet truck 14 (the width direction of the endless track 13). Refrigerant is supplied to the supply pipe 51 . A plurality of nozzles 52 extend downward from the supply pipe 51 . Each nozzle 52 discharges the coolant supplied to the supply pipe 51 toward the sintering bed on the pallet truck 14 .

[Groove forming device]
Returning to FIG. 1, the groove forming device 60 is a device for forming grooves in the raw material bed on the pallet truck 14 . The groove forming device 60 is provided above the sintering machine body 10 . The grooving device 60 is arranged upstream of the ignition furnace 30 in the direction of travel of the pallet truck 14 . The grooving device 60 is arranged between the charging device 20 and the ignition furnace 30 .

Hereinafter, the groove forming device 60 will be described in detail with reference to FIGS. 3 to 5. FIG.

FIG. 3 is a front view of the grooving device 60. FIG. As shown in FIG. 3, the grooving device 60 has at least one disk 61, a shaft member 62, a scraper 63, and at least one position adjusting mechanism 64. As shown in FIG. In this embodiment, the groove forming device 60 has a plurality of discs 61 and a plurality of position adjustment mechanisms 64 corresponding to the plurality of discs 61 .

(Disc and shaft member)
The plurality of discs 61 are arranged along the width direction of the pallet truck 14 (the width direction of the endless track 13). Each disk 61 is arranged so that its thickness direction coincides with the width direction of the pallet truck 14 . Although the material of the disk 61 is not particularly limited, it is steel, for example.

The disc 61 rotates around the centerline 621 of the shaft member 62 . A center line 621 of the shaft member 62 is the rotation axis of the disk 61 . The shaft member 62 passes through a plurality of discs 61 arranged in the width direction of the pallet truck 14 . The disk 61 and the shaft member 62 may be relatively rotatable or integrally rotatable.

FIG. 4 is an enlarged view of one of the discs 61 shown in FIG. As shown in FIG. 4 , the disc 61 has an inner peripheral portion 611 and an outer peripheral portion 612 .

The inner peripheral portion 611 has a through hole 611a. When the disk 61 and the shaft member 62 rotate relative to each other, the shaft member 62 is inserted into the through hole 611a with a gap from the periphery of the through hole 611a. A bearing may be provided between the peripheral edge of the through hole 611 a and the shaft member 62 . When the disk 61 and the shaft member 62 rotate integrally, the disk 61 and the shaft member 62 may be integrally formed, but the relative rotation between the disk 61 and the shaft member 62 may be restricted by radial unevenness. . In this case, the disk 61 rotates integrally with the shaft member 62 and can move relative to the shaft member 62 in the width direction of the pallet truck 14 .

The outer peripheral portion 612 is arranged around the inner peripheral portion 611 . The thickness of the outer peripheral portion 612 decreases from the inner peripheral side to the outer peripheral side of the disk 61 . The outer peripheral portion 612 preferably has tapered surfaces 612 a and 612 b in a vertical cross-sectional view of the disc 61 . The surfaces 612a and 612b are inclined surfaces that are inclined toward each other toward the outer edge of the disc 61 . That is, the outer peripheral portion 612 is substantially V-shaped when viewed in longitudinal section of the disk 61 . However, the surfaces 612a and 612b may be rounded surfaces. The longitudinal section of the disk 61 is a cross section obtained by cutting the disk 61 along a plane including the rotating shaft 621 (the axis of the disk 61).

The length of the outer peripheral portion 612 in the radial direction of the disc 61 is not particularly limited, but can be, for example, approximately 50 mm to 250 mm. The length (thickness) of the outer peripheral portion 612 in the direction perpendicular to the radial direction of the disc 61 is not particularly limited, but can be, for example, about 4 mm to 20 mm. The outer peripheral portion 612 may be formed so that the thickness of the outer peripheral portion is smaller than the thickness of the inner peripheral portion.

The outer peripheral portion 612 is preferably surface-treated to improve wear resistance. The surface treatment may be applied only to the outer peripheral portion 612 or may be applied to the entire disc 61 . The surface treatment can be appropriately selected from, for example, plating such as hard chrome plating, hardfacing welding, and quenching according to the material of the disk 61 and the like.

(scraper)
Continuing to refer to FIG. 4 , scrapers 63 are arranged on both sides of the disk 61 along the outer peripheral portion 612 . Each scraper 63 is arranged so as to sandwich the disk 61 from both sides. The scraper 63 contacts a portion of the surface 612a or 612b of the outer peripheral portion 612 located above the raw material bed R. As shown in FIG.

(position adjustment mechanism)
A position adjusting mechanism 64 is provided for each disc 61 . The position adjustment mechanism 64 adjusts the position of the corresponding disc 61 independently of the other discs 61 . The position adjustment mechanism 64 adjusts the position of the corresponding disk 61 in the width direction of the pallet truck 14 . Further, the position adjusting mechanism 64 can adjust the vertical position of the corresponding disk 61 .

As shown in FIG. 4 , the position adjustment mechanism 64 has a position adjustment member 641 , a support member 642 and a regulation member 643 .

The position adjusting member 641 is, for example, a known feed screw such as a ball screw or slide screw. The position adjusting member 641 has a screw shaft 641a and a nut 641b. The screw shaft 641 a extends in the width direction of the pallet truck 14 . The screw shaft 641a is inserted into the nut 641b. When the position adjusting member 641 is a ball screw, a plurality of rolling elements (not shown) are arranged between the screw shaft 641a and the nut 641b.

The support members 642 are arranged on both sides of the disc 61 . The disk 61 is sandwiched between two support members 642 in the vicinity of the shaft member 62 . These support members 642 depend from the positioning member 641 . The upper end of each support member 642 is attached to a nut 641b. A scraper 63 is arranged between the two support members 642 .

The regulating member 643 is arranged below the position adjusting member 641 . The restricting member 643 extends in the width direction of the pallet truck 14 and penetrates the two supporting members 642 . The restricting member 643 is fixed so as not to rotate around the axis.

With the configuration as described above, the position adjusting mechanism 64 can appropriately move the disk 61 in the width direction of the pallet truck 14 . By rotating the screw shaft 641a of the position adjusting member 641 about its axis, the nut 641b moves in the width direction of the pallet truck 14 along the screw shaft 641a. Since the disk 61 is connected to the nut 641b via the support member 642, it moves in the width direction of the pallet truck 14 together with the nut 641b. The restricting member 643 restricts the nut 641b, the support member 642, and the disk 61 from rotating together with the rotation of the screw shaft 641a.

FIG. 5 is a side view of the grooving device 60 shown in FIG. Referring to FIG. 5 , a plurality of position adjusting mechanisms 64 provided corresponding to a plurality of discs 61 are arranged with their positions shifted in the circumferential direction of disc 61 . Therefore, the position adjusting members 641 and the restricting members 643 of the plurality of position adjusting mechanisms 64 do not interfere with each other.

In this embodiment, the restricting member 643 is provided for each disc 61 , but a common restricting member 643 may be provided for two or more discs 61 . In this embodiment, each disk 61 is provided with a screw shaft 641a (FIG. 4) to move each disk 61 individually. , and these discs 61 may be moved simultaneously.

Position adjustment member 641 is preferably a lead screw so that the position of disk 61 can be adjusted by manipulation of its end. However, the configuration of the position adjusting member 641 is not limited to this. For example, the position adjusting member 641 may be composed of a threadless rod extending in the width direction of the pallet truck 14 and a sleeve slidably attached to the rod.

(Pressing mechanism)
As shown in FIG. 5 , the grooving device 60 can further have a pressing mechanism 65 provided for each disc 61 . The pressing mechanism 65 includes a pressing plate 651 and a guide member 652 . One surface (lower surface) of the pressing plate 651 faces the surface of the raw material bed R of the pallet truck 14 . The pressing plate 651 has a slit (not shown) extending in the running direction of the pallet truck 14, and the outer peripheral portion 612 of the disk 61 is inserted into this slit. The guide members 652 are arranged on both sides of the disc 61 . Each guide member 652 is generally formed in an inverted U shape and is mounted on the shaft member 62 from above. Each guide member 652 and shaft member 62 are relatively movable in the vertical direction. A lower end portion of the guide member 652 is connected to the upper surface of the pressing plate 651 .

<Operation of sintering machine>
Next, the operation of the sintering machine 1 configured as described above will be described.

Referring again to FIG. 1 , when the sintering machine 1 produces sintered ore, the charging device 20 charges the raw material for sintering to the pallet truck 14 traveling on the forward route of the endless track 13 . Specifically, the bedding hopper 21 supplies bedding ore to the pallet truck 14 passing below the charging device 20, and the surge hopper 22 supplies sintering raw material onto this bedding ore. As a result, a raw material bed R is formed on the pallet truck 14 .

A plurality of grooves G are formed in the raw material bed R on the pallet truck 14 by the groove forming device 60 . 3 and 4, when the pallet truck 14 passes through the grooving device 60, each disk 61 contacts the raw material bed R on the pallet truck 14 and rotates around the rotation axis 621. As shown in FIG. In this embodiment, each disc 61 rotates around the shaft member 62 only by contacting the raw material bed R moving on the outward path. However, each disc 61 may be rotated together with the shaft member 62 by rotating the shaft member 62 with a driving device (not shown) connected to the shaft member 62 .

The outer peripheral portion 612 of each rotating disk 61 penetrates into the raw material bed R, and a groove G is formed in the raw material bed R. The outer peripheral portion 612 forms the groove G while pushing the sintering raw material of the raw material bed R apart. Since the thickness of the outer peripheral portion 612 decreases from the inner peripheral side to the outer peripheral side of the disk 61, a groove G whose width decreases downward is formed in the raw material bed R. The pressing plate 651 of the pressing mechanism 65 follows the surface of the raw material bed R by the weight of the pressing mechanism 65, and presses the surface of the raw material bed R on both sides of the disk 61 while the outer peripheral portion 612 forms the groove G. do. As a result, the sintering raw material pushed to the outer peripheral portion 612 can be prevented from rising on both sides of the groove G. As shown in FIG.

When forming the grooves G in the raw material bed R, the surface of the disk 61 can be moistened with water or the like. As a result, the friction between the sintering raw material and the disc 61 can be reduced, and the adhesion of the sintering raw material to the disc 61 can be prevented. A carbon component may be added to the raw material bed R in which the grooves G are formed in order to suppress the generation of return fines.

Here, the state of formation of the grooves G by the disk 61 will be described with reference to FIG. 6A and 6B are a plan view and a side view of a disk 61 forming grooves G in the raw material bed R. FIG.

As shown in FIG. 6, the outer peripheral portion 612 of the rotating disk 61 forms a groove G in the raw material bed R being transported from the ore supplying section 11 side to the ore discharging section 12 side. The outer peripheral portion 612 bites into the raw material bed R to spread the sintering raw material in the thickness direction of the disk 61 at the lowermost point P of the locus of rotation of the disk 61 . Complete the groove G. On the side of the ore discharge portion 12 from the lowest point P, the outer peripheral portion 612 exits the completed groove G. On the side of the ore discharge section 12 from the lowest point P, the tapered outer peripheral portion 612 moves upward as the disc 61 rotates, and a portion of the outer peripheral portion 612 having a thickness smaller than the width of the groove G is expanded. Since it passes through the groove G, the outer peripheral portion 612 does not come into contact with the inner surface of the groove G that has already been formed. When the sintering raw material adheres to the outer peripheral portion 612 that has escaped from the groove G, this sintering raw material is scraped off from the outer peripheral portion 612 by the scraper 63 (FIG. 3).

Returning to FIG. 1 , the raw material for sintering on the pallet truck 14 is ignited by the ignition furnace 30 after the grooves G are formed by the groove forming device 60 . As a result, coke in the raw material for sintering starts burning.

After ignition by the ignition furnace 30 , the pallet truck 14 travels through the firing zone 16 . While traveling in the firing zone 16, coke in the sintering raw material is burned, iron ore is partially melted, and agglomeration of the sintering raw material proceeds. In the calcining zone 16, the intake air from the windbox 15 promotes coke combustion. Further, the exhaust gas from the wind box 15 of the cooling zone 17 is supplied into the circulation hood 42, thereby promoting coke combustion.

The pallet truck 14 loaded with the sintering bed and traveling is exposed between the circulation hoods 42 and 43 , that is, between the baking zone 16 and the cooling zone 17 . Between the firing zone 16 and the cooling zone 17 the sinter bed on the pallet truck 14 is cooled. In this embodiment, the coolant is supplied from the coolant supply device 50 to the sintering bed on the pallet truck 14 . Specifically, the coolant discharged from each nozzle 52 ( FIG. 2 ) of the coolant supply device 50 is injected into each of the grooves G formed by the disk 61 . A nozzle 52 is provided for each groove G, that is, for each disc 61 . However, the number and arrangement of the nozzles 52 are not limited to this.

The pallet truck 14 then travels through the cooling zone 17 . In the cooling zone 17 , the sintering completion zone and the combustion/melting zone of the sintering bed are cooled by the intake air from the wind box 15 . The exhaust gas from the wind box 15 in the cooling zone 17 is circulated to the circulation hood 42 in the firing zone 16 as described above in order to reduce the amount of exhaust gas in the sintering machine body 10 . While the pallet truck 14 is traveling through the cooling zone 17, the sintering raw material on the sintering bed is burned off. The sintered bed after baking (after firing is completed) is called a sintered cake.

The pallet carriage 14 is turned back by the driven sprocket wheel 132 on the side of the ore discharge section 12 and travels on the return route. The sintered cake is discharged from the pallet truck 14 when the pallet truck 14 turns. The sintered cake is crushed by crusher 70 and cooled by cooler 80 . In this embodiment, since the sintering bed is cooled in the cooling zone 17 of the sintering machine main body 10, the cooling machine 80 may be simple.

<Effects of Embodiment>
In the sintering machine 1 according to this embodiment, the grooves G are formed in the raw material bed R on the pallet truck 14 by the outer peripheral portion 612 of the rotating disc 61 . The sintering raw material in the raw material bed R is pushed apart while receiving a downward force due to the rotation of the disk 61 and the tapered surface shape of the outer peripheral portion 612 . Therefore, when the outer peripheral portion 612 separates from the completed groove G, it is possible to prevent the sintering raw material on the inner surface of the groove G from collapsing. Therefore, the groove G having a smooth inner surface can be formed in the raw material bed R.

The outer peripheral portion 612 spreads the raw material for sintering from the surface of the raw material bed R to the lowest point P of the locus of rotation of the disk 61 to complete the groove G. As shown in FIG. After that, the outer peripheral portion 612 exits the completed groove G as the disk 61 rotates. The outer peripheral portion 612 is formed so that the thickness decreases from the inner peripheral side to the outer peripheral side, and since the portion with the greater thickness comes out of the groove G in order, it does not come into contact with the inner surface of the groove G. Therefore, the inner surface of the groove G formed in the raw material bed R can be maintained in a smooth state.

As described above, according to the present embodiment, by forming the grooves G with smooth inner surfaces in the raw material bed R, it is possible to prevent the generation of portions where the density of the sintering raw material is low in the raw material bed R. Therefore, the generation of return ores can be suppressed.

In this embodiment, the outer peripheral portion 612 of the disc 61 preferably has tapered surfaces 612a and 612b in a vertical cross-sectional view. The surfaces 612a and 612b can spread the sintering raw material of the raw material bed R uniformly. Therefore, the inner surface of the groove G formed in the raw material bed R can be made smoother more reliably, and the generation of return ore is further suppressed.

In this embodiment, the outer peripheral portion 612 is preferably surface-treated to improve wear resistance. As a result, wear of the outer peripheral portion 612 due to contact with the raw material for sintering is suppressed, and the life of the disk 61 can be extended.

In this embodiment, scrapers 63 provided on both sides of the disk 61 along the outer peripheral portion 612 can remove the sintering raw material adhering to the outer peripheral portion 612 of the disk 61 each time. This can prevent the sintered material adhering to the surfaces 612a and 612b of the outer peripheral portion 612 from growing into lumps. Therefore, it is possible to prevent the shape of the groove G from changing due to adhesion of the sintered material to the outer peripheral portion 612 .

In this embodiment, the position adjustment mechanism 64 can adjust the position of each disk 61 in the width direction of the pallet truck 14 (the width direction of the endless track 13). Thereby, the groove G can be formed at a desired position according to the ventilation state of the raw material bed R or the sintering bed.

In this embodiment, grooves G are formed in the raw material bed R on the pallet truck 14 before ignition. Thus, when the ignition furnace 30 ignites the sintering material in the raw material bed R and the pallet truck 14 passes through the sintering zone 16, the air around the pallet truck 14 flows through the pre-formed grooves G into the sintering bed. influx. Of the sintering bed, the portion where the grooves G are formed has a lower layer height than the portion where the grooves G are not formed, and has a smaller ventilation pressure loss, so much air is sucked in. The air sucked into the groove G also diffuses around the groove G within the sintering bed. Therefore, the combustion of coke contained in the raw material for sintering is promoted, and the firing rate can be improved.

Further, in the sintering machine 1 according to the present embodiment, after the pallet truck 14 has passed through the firing zone 16, the sintering bed on the pallet truck 14 is cooled. By forming the grooves G in the sintering bed, the cooling of the sintering bed can be promoted.

7 to 9 show the reaction state of the sintered layer on the pallet truck 14 running from the ignition furnace 30 to the ore discharge section 12. FIG. FIG. 7 is a longitudinal sectional view of a sintered layer SLa formed by a conventional sintering machine. 8 and 9 are longitudinal sectional views of sintered layers SLb and SLc formed by the sintering machine 1 according to this embodiment. 8 shows the sintered layer SLb when the coolant supply device 50 does not supply the coolant, and FIG. 9 illustrates the sintered layer SLc when the coolant supply device 50 performs the coolant supply.

As shown in FIGS. 7 to 9, after the sintering material is ignited by the ignition furnace 30, while the pallet truck 14 is traveling toward the ore discharge section 12, the sintered layers SLa, SLb, and SLc are formed. Firing progresses from the surface toward the grate surface (upper surface of the grate bar of the pallet truck 14). As the firing progresses, the combustion/melting zone gradually moves downward. Here, the point where the lower boundary line L1 of the combustion/melting zone reaches the grate surface is the combustion front arrival point FFP, and the point where the upper boundary line L2 of the combustion/melting zone reaches the grate surface is the sintering completion point. Define BTP.

A conventional sintering machine does not have a grooving device 60 . Therefore, the groove G does not exist in the sintered layer SLa of the conventional sintering machine. A conventional sintering machine (not shown) does not have a zone in the middle of the circulating hood for sucking the atmosphere, and the hot circulating gas is uniformly supplied to the sintering bed. Therefore, even in the cooling zone, a high temperature gas of about 200° C. is supplied to the sintered layer. Therefore, the layer height (thickness) of the combustion/melting zone is increased, and the pressure loss of gas flow is increased. On the other hand, the present inventors proposed a sintering machine provided with a zone for sucking air between the circulation hood 42 of the firing zone 16 and the circulation hood 43 of the cooling zone 17 in the above-mentioned Patent Document 6. did. FIG. 7 shows a longitudinal sectional view of the sintered layer SLa formed by the sintering machine proposed in Patent Document 6. As shown in FIG.

In the sintered layer SLa, when the thickness of the high-temperature combustion/melting zone increases, the melted portion becomes closed pores, blocking the passage of gas. As a result, there is a problem that the pressure loss of passing gas in the sintered layer SLa increases. Therefore, it is necessary to operate the sintering machine so that the thickness of the combustion/melting zone does not exceed an appropriate thickness. However, as shown in FIG. 7, in the sintering machine of the type that cools the sintered layer SLa on the sintered strand, the sintering zone 16 and the cooling zone 17 are continuous. There was a problem that the running speed could not be slowed down to promote cooling. Therefore, the running speed of the pallet truck 14 must be adjusted to the slower one of the firing speed and the cooling speed. It was an operation that had to reduce the running speed and lower the production efficiency. In the sintered layer SLa shown in FIG. 7, the combustion/melting zone extends in the layer height direction also in the cooling zone 17 . Therefore, if there are still many closed pores in the sintered layer SLa, that is, if the gas pressure loss is high, further acceleration of cooling is required. Once the closed pores are generated and solidified, even if the temperature of the portion where the closed pores are generated drops, the ventilation resistance of the portion remains high. In FIG. 7, the phase above the combustion/melting zone is the fully solidified sintered completion zone. Therefore, it is important to reduce the thickness of the combustion/melting zone.

On the other hand, the sintering machine 1 according to this embodiment has a groove forming device 60 . Therefore, as shown in FIGS. 8 and 9, grooves G are formed in advance in the sintered layers SLb and SLc of the sintering machine 1 . According to the sintering machine 1, regarding the airflow resistance improvement and cooling promotion of the sintered layers SLb and SLc, it is possible to respond in two steps: forming the grooves G by the groove forming device 60 and then injecting a coolant such as water. becomes.

In FIG. 8, the boundary lines L1 and L2 of the combustion/melting zones in the sintering layer SLb of the sintering machine 1 according to the present embodiment are indicated by solid lines, and the boundaries of the combustion/melting zones in the sintering layer SLa of the conventional sintering machine are indicated by solid lines. Lines L1 and L2 are indicated by dashed lines. As shown in FIG. 8, in the sintered layer SLb of the sintering machine 1, the combustion front arrival point FFP and the sintering completion point BTP are closer to the firing zone 16 than in the sintered layer SLa of the conventional sintering machine. moving. That is, in the case of the sintering machine 1, the layer height of the combustion/melting zone in the cooling zone 17 is smaller than that of the conventional sintering machine. This is because the air can easily reach the combustion/melting zone through the grooves G, and as a result, cooling of the sintered layer between the firing zone 16 and the cooling zone 17 is accelerated.

In addition, the sintered layer SLb of the sintering machine 1 has a reduced layer height of the combustion/melting zone in the sintering zone 16 compared to the sintered layer SLa of the conventional sintering machine. This is because in the sintering zone 16 as well, a large amount of air flowed into the sintered layer SLb through the grooves G, increasing the sintering speed.

Thus, the sintering machine 1 according to the present embodiment forms the grooves G in the sintered layer SLb to reduce the layer height of the combustion/melting zone and improve the air permeability of the sintered layer SLb. can be done. When the air permeability is improved, the firing rate and the cooling rate are increased, so the productivity of the sintered ore can be improved.

Furthermore, when a coolant such as water is supplied to the groove G between the firing zone 16 and the cooling zone 17, the layer height of the combustion/melting zone in the cooling zone 17 is further reduced. In FIG. 9, in the sintering machine 1 according to the present embodiment, the solid line represents the boundary line L2 of the combustion/melting zone of the sintered layer SLc to which the coolant is supplied, and the combustion/melting zone of the sintered layer SLb to which the coolant is not supplied. is indicated by a dashed line.

As shown in FIG. 9, the sintering completion point BTP of the sintered layer SLc has moved toward the sintering zone 16 compared to the sintered layer SLb. In the sintered layer SLc, after the coolant is supplied to the grooves G between the firing zone 16 and the cooling zone 17, the layer height of the combustion/melting zone rapidly decreases, and in the cooling zone 17, the combustion/melting zone is Almost non-existent. This further improves the air permeability of the sintered layer SLc and increases the cooling rate. Therefore, productivity of sintered ore can be improved more.

In this embodiment, the grooves G may be supplied with calcium. For example, fine powder of quicklime, slaked lime, or the like, or dust containing calcium can be carried in the airflow and supplied to the groove G. As a result, the salt concentration on the surface of the combustion/melting zone increases and the surface is cooled, so that the solidification of the melt can be promoted.

Although the embodiments according to the present disclosure have been described above, the present disclosure is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present disclosure.

In the above embodiment, the sintering machine main body 10 is provided with the firing zone 16 and the cooling zone 17, but the cooling zone 17 may not be provided. That is, the sintering machine main body 10 may burn off the sintering raw material to generate sintered ore, and then discharge the sintered ore without cooling it.

Although the sintering machine 1 includes the coolant supply device 50 in the above embodiment, the coolant supply device 50 may not be included. As described above, even when the coolant is not supplied from the coolant supply device 50 to the grooves G, good air permeability can be ensured in the sintered layer.

In the above embodiment, the groove forming device 60 has the pressing mechanism 65 that presses the surface of the raw material bed while forming the grooves G. As shown in FIG. However, the surface of the raw material bed may be pressed after forming the grooves G, or the mechanism itself for pressing the raw material bed may not exist.

1: Sintering Machine 13: Endless Track 14: Pallet Truck 30: Ignition Furnace 61: Disk 612: Outer Periphery 612a, 612b: Surface 621: Rotating Shaft 63: Scraper 64: Position Adjusting Mechanism

Claims (4)

A pallet truck loaded with raw materials for sintering and running on an endless track;
an ignition furnace that ignites the sintering raw material on the pallet truck;
a plurality of discs arranged upstream of the ignition furnace in the running direction of the pallet truck and rotating around a rotation axis extending in the width direction of the endless track;
a plurality of position adjusting mechanisms for adjusting positions of the plurality of discs in the width direction of the endless track independently of each other;
with
each of said discs comprising:
An outer peripheral portion that penetrates into the sintering raw material on the pallet truck to form a groove, the outer peripheral portion formed so that the thickness decreases from the inner peripheral side to the outer peripheral side of the disk,
A sintering machine. A sintering machine according to claim 1,
The sintering machine, wherein the outer peripheral portion has a tapered surface when viewed in a cross section taken along a plane that passes through the center of the disk and includes the rotation axis. The sintering machine according to claim 1 or 2,
The sintering machine, wherein the outer peripheral portion is subjected to a surface treatment for improving wear resistance. A sintering machine according to any one of claims 1 to 3, further comprising:
Scrapers arranged on both sides of the disk along the outer periphery above the sintering raw material on the pallet truck;
a sintering machine.

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