JP7119936B2 - 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 Literatures 1 and 2 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 1 and 2, the thickness of the charged 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 3, 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 4 discloses a method of charging raw materials for sintering into a sintering machine. In Patent Document 4, a plurality of slit-shaped 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 4, 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.

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

In Patent Documents 1 to 4, grooves are formed in the sintering raw material as the pallet truck travels by inserting and fixing a rod-shaped body or plate-shaped body into the sintering raw material. In this case, the sintering raw material pushed apart by the rod-shaped body or plate-shaped body rises on both sides of the groove. The sintering raw material piles raised on both sides of the grooves are portions where the density of the raw material particles is low, so return fines generated during the sintering operation increase.

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 When the sintering raw material rises on both sides of the groove as described above, even if the ignition furnace ignites this raised portion and the coke in the sintering raw material burns, the surface of the sintering layer (sintering bed) There is little heat storage in the ridges at , leading to insufficient melting of the slag components. Therefore, the protruding portion is weak in strength, and easily collapses into fine granules due to a slight external force such as a drop impact during the transportation process. Even if no ridges were present, the surface of the sinter bed on the pallet truck would be susceptible to return fines due to its weak strength due to little heat storage. 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 Literature 2, a cut-off gate is arranged downstream of the vent bar forming the groove. The sintering raw material raised on both sides of the groove is pressed downward by this cut-off gate, and the surface of the sintering raw material is flattened. However, the sintering raw material pressed by the cut-off gate may flow into the groove, collapsing the groove formed by the vent bar. In this case, a portion where the density of the raw material particles is low is generated, resulting in an increase in return fines.

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 grooving device. 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 grooving device is arranged upstream of the ignition furnace in the direction of travel of the pallet truck. The grooving device has an intruder and a pressing body. The intruders penetrate and form grooves in the sintering material on the pallet truck. The pressing body includes a pressing surface. The pressure surfaces are arranged on both sides of the intruder in the direction of travel. The pressing surface presses the surface of the raw material for sintering on the pallet truck. The pressing surface extends at least from the upstream end of the intruder to the maximum width in said running direction. The maximum width portion is the portion of the intruder that has the maximum length in the width direction of the endless track.

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 a partially enlarged view of the groove forming device shown in FIG. 3. FIG. 5 is a side view of the grooving device shown in FIG. 3; FIG. FIG. 6 is a diagram for explaining the action of the pressing mechanism included in the groove forming device shown in FIGS. 3 to 5. FIG. 7A and 7B are diagrams for explaining the action of a pressing mechanism different from the pressing mechanism in FIG. 6. FIG. FIG. 8 is a vertical cross-sectional view of a sintered layer formed by a sintering machine before the sintering machine according to the embodiment. 9 is a longitudinal sectional view of a sintered layer formed by the sintering machine shown in FIG. 1. FIG. 10 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 groove forming device. 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 grooving device is arranged upstream of the ignition furnace in the direction of travel of the pallet truck. The grooving device has an intruder and a pressing body. The intruders penetrate and form grooves in the sintering material on the pallet truck. The pressing body includes a pressing surface. The pressure surfaces are arranged on both sides of the intruder in the direction of travel. The pressing surface presses the surface of the raw material for sintering on the pallet truck. The pressing surface extends at least from the upstream end of the intruder to the maximum width in said running direction. The maximum width portion is a portion of the intruder having the maximum length in the width direction of the endless track (first configuration).

In the first configuration, the penetrating body penetrates into the sintering raw material on the pallet truck from the upstream end to start forming the groove, and completes the formation of the groove at the maximum width portion. The pressing surface of the pressing body presses the surface of the sintering raw material on both sides of the intruding body at least in the range from the upstream end of the intruding body to the maximum width portion. That is, while the groove is being formed in the sintering raw material by the intruder, the surface of the sintering raw material is pressed by the pressing surfaces on both sides of the groove in the process of being formed. Therefore, when the groove is formed, it is possible to prevent the sintering raw material from rising on both sides of the groove, thereby suppressing the generation of return fines. As described above, according to the first configuration, grooves are formed in the sintering raw material to reduce the airflow resistance of the sintering raw material and to suppress the generation of return ores.

It is preferable that the pressing surface extends upstream of the upstream end of the intruder in the running direction of the pallet truck (second configuration).

According to the second configuration, the pressing surface can start pressing the surface of the sintering raw material before the intruder enters the sintering raw material and starts forming the grooves. Therefore, it is possible to more reliably prevent the sintering raw material from rising on both sides of the groove.

It is preferable that the pressing body is attached to the intruding body so that it can move up and down relative to the intruding body (third configuration).

According to the third configuration, the pressing body moves up and down relative to the intruding body. Therefore, even if the height of the surface of the sintering raw material moves up and down with respect to the intruding body due to changes in layer pressure of the sintering raw material, the pressing surface of the pressing body can follow the surface of the sintering raw material. can be done. Therefore, the surface of the sintering raw material can be reliably pressed regardless of changes in the layer thickness of the sintering raw material.

The intruder may be fixed inserted into the sintering material on the pallet truck. In this case, it is preferable that the position of the downstream end of the pressing surface coincides with the position of the downstream end of the maximum width portion in the traveling direction of the pallet truck (fourth configuration).

When the sintering raw material on the pallet truck is fixed with the intruder inserted therein, grooves are formed in the sintering raw material as the pallet truck travels. At this time, the groove is completed at the position of the maximum width portion of the intruder, but if the surface of the sintering raw material is pressed until after the groove is completed, the completed groove may collapse. Therefore, in the fourth configuration, the position of the downstream end of the pressing surface is matched with the position of the downstream end of the maximum width portion of the intruder. As a result, the surface of the raw material for sintering is not pressed by the pressing surface on the downstream side of the maximum width portion of the intruding body, so that collapse of the groove can be prevented.

Preferably, the pressing body further includes a peripheral surface. The peripheral surface faces the sintering stock on the pallet truck. The peripheral surface is provided around the pressing surface and rises outward from the pressing surface (fifth configuration).

According to the fifth configuration, since the peripheral edge surface rising outward from the pressing surface is provided, it is possible to prevent the surface of the raw material for sintering from being roughened by the edge of the pressing surface.

In the sintering machine, the pallet truck can travel through the firing zone and the cooling zone. The sintering zone advances the sintering raw material on the pallet truck. A cooling zone is arranged downstream of the baking zone in the direction of travel of the pallet truck. The cooling zone cools the sintering raw material fired in the firing zone. A coolant is preferably injected into the groove between the firing zone and the cooling zone (sixth configuration).

According to the sixth configuration, after the raw material for sintering on the pallet truck is fired in the firing zone, the coolant is injected into the grooves formed in advance in the raw material for sintering. Therefore, cooling of the sintered raw material after firing can be accelerated in the cooling zone located downstream of the firing zone.

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 intruder 61 , a shaft member 62 , a scraper 63 , at least one position adjusting mechanism 64 and at least one pressing mechanism 65 . In this embodiment, grooving device 60 has a plurality of intruders 61 . The groove forming device 60 is provided with a plurality of position adjusting mechanisms 64 and pressing mechanisms 65 corresponding to the plurality of intruding bodies 61, respectively.

(Intruder and shaft member)
The multiple intruders 61 are arranged along the width direction of the pallet truck 14 (the width direction of the endless track 13). In this embodiment, each intruder 61 is disk-shaped. However, the shape of the intruder 61 is not limited to this. The intruding body 61 may be a rod-shaped body or a plate-shaped body other than a disc. In this embodiment, each disk-shaped intruder 61 is arranged so that its thickness direction coincides with the width direction of the pallet truck 14 . Although the material of the intruding body 61 is not particularly limited, it is steel, for example.

The intruder 61 rotates around the center line (rotational axis) 621 of the shaft member 62 . The shaft member 62 passes through a plurality of intrusive bodies 61 arranged in the width direction of the pallet truck 14 . The penetrating body 61 and the shaft member 62 may be relatively rotatable or integrally rotatable. The intruder 61 may be a non-rotating rod or plate. If the intruder 61 does not rotate, the shaft member 62 is not necessary.

FIG. 4 is a partially enlarged view of the grooving device 60 shown in FIG. As shown in FIG. 4 , the disk-shaped intruder 61 has a through hole 611 . When the intruding body 61 and the shaft member 62 rotate relative to each other, the shaft member 62 is inserted into the through hole 611 with a gap between it and the periphery of the through hole 611 . A bearing may be provided between the peripheral edge of the through hole 611 and the shaft member 62 . When the intruding body 61 and the shaft member 62 rotate integrally, the intruding body 61 and the shaft member 62 may be integrally formed, but the relative rotation of the intruding body 61 and the shaft member 62 may be restricted by radial unevenness. . In this case, the intruder 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 intruder 61 intrudes into the raw material bed R on the pallet truck 14 to form a groove G. More specifically, the outer peripheral portion 612 of the intruder 61 intrudes into the raw material bed R. The outer peripheral portion 612 is formed such that its thickness gradually decreases from the inner peripheral side toward the outer peripheral side. In this case, both surfaces of the outer peripheral portion 612 are, for example, inclined surfaces or arcuate surfaces that approach each other toward the outer peripheral side. However, both surfaces of the outer peripheral portion 612 may extend in parallel. That is, the outer peripheral portion 612 may have a constant thickness from the inner peripheral side to the outer peripheral side.

The length of the outer peripheral portion 612 in the radial direction of the intruder 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 intruder 61 is not particularly limited, but can be, for example, about 4 mm to 20 mm.

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 penetrating body 61 . The surface treatment can be appropriately selected from, for example, plating such as hard chrome plating, hardfacing welding, and quenching depending on the material of the intruding body 61 .

(scraper)
Scrapers 63 are arranged on both sides of the intruder 61 . Each scraper 63 is arranged so as to sandwich the intruder 61 from both sides. Above the raw material bed R, the scraper 63 contacts the surface of the intruder 61 .

(position adjustment mechanism)
A position adjustment mechanism 64 is provided for each intruder 61 . The position adjustment mechanism 64 adjusts the position of the corresponding intruder 61 independently of the other intruders 61 . The position adjustment mechanism 64 adjusts the position of the corresponding intruder 61 in the width direction of the pallet truck 14 . Further, the position adjusting mechanism 64 can adjust the vertical position of the corresponding intruding body 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 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. That is, the position adjusting member 641 of this embodiment is a known feed screw such as a ball screw or slide screw. 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. However, the position adjusting member 641 may not be a feed screw. For example, the position adjusting member 641 can be configured with a threadless rod extending in the width direction of the pallet truck 14 and a sleeve slidably attached to the rod.

The support members 642 are arranged on both sides of the intruder 61 . The penetrating body 61 is sandwiched between two support members 642 near 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 intruder 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 intruder 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 supporting member 642, and the intruding body 61 from rotating together with the rotation of the screw shaft 641a.

The position adjusting mechanism 64 provided for each intruding body 61 can be displaced in the circumferential direction of the intruding body 61 so that the position adjusting member 641 and the restricting member 643 do not interfere with each other. The threaded shaft 641 a of the position adjusting member 641 may be provided for each intruding body 61 , or may be provided in common for two or more intruding bodies 61 . Similarly, the restricting member 643 may be provided for each intruder 61 , but may be provided in common for two or more intruders 61 .

(Pressing mechanism)
Continuing to refer to FIG. 4, the pressing mechanism 65 presses the surface of the raw material bed R while the intruder 61 forms the groove G in the raw material bed R. As shown in FIG. The pressing mechanism 65 can be made of the same material as the intruder 61 . The pressing mechanism 65 includes a pressing body 651 and a guide member 652 .

Although the shape of the pressing body 651 is not particularly limited, it is, for example, a plate shape. The pressing body 651 has a slit 651a extending in the running direction of the pallet truck 14 . The outer peripheral portion 612 of the intruding body 61 rotating around the rotating shaft 621 is inserted into the raw material bed R on the pallet truck 14 through the slit 651a.

5 is a side view of the grooving device 60. FIG. As shown in FIG. 5, the pressing body 651 has a pressing surface 651b and a peripheral edge surface 651c. The pressing surface 651b and the peripheral edge surface 651c form the lower surface of the pressing body 651 and face the surface of the raw material bed R.

The pressing surface 651b contacts the surface of the raw material bed R. Although details will be described later, the pressing surface 651b presses the surface of the raw material bed R on both sides of the groove G formed by the intruding body 61 . The pressing surface 651 b can press the surface of the raw material bed R by the weight of the pressing mechanism 65 . The pressing force of the pressing surface 651b can also be adjusted by placing a weight on the pressing body 651, for example.

The peripheral surface 651c rises outward from the pressing surface 651b so as not to come into contact with the raw material bed R. The peripheral surface 651c is preferably arranged to surround the pressing surface 651b. That is, it is preferable that the peripheral edge surface 651c is provided over the entire circumference of the pressing surface 651b. However, the peripheral edge surface 651c may be provided on a part of the outer periphery of the pressing surface 651b. For example, in the running direction of the pallet truck 14, the peripheral surface 651c can be provided only on the upstream end side and/or the downstream end side of the pressing surface 651b. The peripheral edge surface 651c may be an inclined surface or an arcuate surface in a vertical cross-sectional view of the pressing body 651 .

Continuing to refer to FIG. 5 , a guide member 652 is provided on the side of the intruder 61 . In this embodiment, guide members 652 are provided on both sides of the intruder 61 . Each guide member 652 is generally formed in an inverted U shape when the groove forming device 60 is viewed from the side. Each guide member 652 includes a horizontal portion 652a and vertical portions 652b, 652c.

The horizontal portion 652 a extends along the running direction of the pallet truck 14 above the shaft member 62 . The vertical portion 652b extends vertically on the upstream side of the shaft member 62 in the running direction of the pallet truck 14 . The vertical portion 652c extends vertically downstream of the shaft member 62 in the running direction of the pallet truck 14 . Upper ends of the vertical portions 652b and 652c are connected to the horizontal portion 652a. Each lower end of the vertical portions 652 b and 652 c is connected to the upper surface 651 d of the pressing body 651 .

The shaft member 62 is inserted into a space 653 defined by the horizontal portion 652 a and vertical portions 652 b and 652 c of the guide member 652 and the pressing body 651 . The vertical length of the space 653 is greater than the diameter of the shaft member 62 . Therefore, the pressing mechanism 65 can move up and down relative to the shaft member 62 and the intrusion body 61 into which the shaft member 62 is inserted. For example, when the layer thickness of the raw material bed R changes, the pressing mechanism 65 moves up and down due to its own weight to follow the surface of the raw material bed R.

Next, the area of the raw material bed R on the pallet truck 14 that is pressed by the pressing surface 651b of the pressing body 651 will be described with reference to FIGS. 6 and 7. FIG. 6 shows a cross section CS1 obtained by cutting the intruding body 61 along the surface of the raw material bed R and a pressing surface 651b of the pressing body 651. FIG. FIG. 7 shows another penetrating body 610 and pressing body 6510 . FIG. 7 shows a cross section CS2 of the intruding body 610 cut along the surface of the raw material bed R and a pressing surface 6510b of the pressing body 6510. FIG.

Referring to FIG. 6, intruder 61 causes outer peripheral portion 612 to intrude into raw material bed R while rotating around rotating shaft 621 . The outer peripheral portion 612 is formed such that its thickness gradually decreases from the inner peripheral side to the outer peripheral side. In this case, the penetration body 61 has the maximum width (the length in the width direction of the pallet truck 14) at the center position in the running direction of the pallet truck 14, that is, at the position of the rotation shaft 621, as viewed in the cross section CS1. A portion of the intrusion body 61 having the maximum width as viewed in the cross section CS1 is referred to as a maximum width portion W1max.

The pressing surface 651b of the pressing body 651 presses the surface of the raw material bed R at least in a range A11 from the upstream end E1u of the intruding body 61 to the maximum width W1max on both sides of the intruding body 61 (groove G). In this embodiment, the pressing surface 651b extends further upstream than the upstream end E1u of the intruder 61, and also presses a range A12 of the surface of the raw material bed R on the upstream side from the upstream end E1u of the intruder 61. The pressing surface 651b extends downstream from the maximum width portion W1max of the intruding body 61 and further extends downstream from the downstream end E1d of the intruding body 61 . The pressing surface 651b also presses a downstream area A13 of the surface of the raw material bed R from the maximum width W1max of the intruding body 61 .

Although the intrusion body 61 is rotated in this embodiment, the intrusion body 61 may be inserted into the raw material bed R and fixed without being rotated. In this case, it is preferable to configure the pressing body 651 such that the position of the downstream end of the pressing surface 651b coincides with the position of the maximum width portion W1max of the intruding body 61 in the running direction of the pallet truck 14 . That is, when the intruder 61 is fixed, it is preferable that the portion of the surface of the raw material bed R on the downstream side of the maximum width W1max is not pressed by the pressing surface 651b.

As shown in FIG. 7, intruder 610 has a constant width in cross section CS2. In this case, when viewed from the cross section CS2, the entire intruder 610 has the maximum width W2max. The pressing surface 6510b of the pressing body 6510 is located on both sides of the intruding body 610 (groove G), at least in a range A21 from the upstream end E2u of the intruding body 610 to the downstream end E2d (the downstream end of the maximum width portion W2max). Press the R surface. In the example shown in FIG. 7, the pressing surface 6510b extends further upstream than the upstream end E2u of the intruder 610, and also presses a range A22 of the surface of the raw material bed R on the upstream side of the upstream end E2u of the intruder 61. do.

The pressing surface 6510b can also press the surface of the raw material bed R further downstream than the downstream end E2d of the intruder 610 . However, when the intruder 610 is inserted into the raw material bed R and fixed, it is preferable that the pressure surface 6510b does not press the surface of the raw material bed R downstream of the downstream end E2d of the intruder 610 . In other words, it is preferable to finish pressing the surface of the raw material bed R by the pressing surface 6510b at the position of the downstream end of the maximum width portion W2max.

<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 intruder 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 intruder 61 rotates around the shaft member 62 only by contacting the raw material bed R moving on the outward path. However, each intruder 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 . If the intrusion body 61 is not configured to be rotatable, the intrusion body 61 is fixed while at least part of the intrusion body 61 is inserted into the raw material bed R.

The outer peripheral portion 612 of each intruding body 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 intruding body 61, a groove G whose width decreases downward is formed in the raw material bed R. As shown in FIG. 5, the pressing surface 651b of the pressing body 651 follows the surface of the raw material bed R by the weight of the pressing mechanism 65, and while the outer peripheral portion 612 forms the groove G, the pressing surface 651b of the pressing body 651 is adjacent to the intruding body 61. The surface of the raw material bed R is pressed. The pressing surface 651b prevents the sintering raw material pushed apart by the outer peripheral portion 612 from rising on the surface of the raw material bed R.

The outer peripheral portion 612 spreads the sintering raw material until it reaches the lowest point of the rotation locus of the intruder 61, and completes the groove G when the lowest point is reached. After that, the outer peripheral portion 612 is removed from the completed groove G. Since the outer peripheral portion 612 tapers toward the outer peripheral side of the intruding body 61 , it does not come into contact with the inner surface of the groove G. That is, as the intruder 61 rotates, the tapered outer peripheral portion 612 is removed upward, so that the portion of the outer peripheral portion 612 having a thickness smaller than the width of the groove G passes through the groove G, and the already formed groove G is removed. The outer peripheral portion 612 does not come into contact with the inner surface of the . 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).

When forming the grooves G in the raw material bed R, the surface of the intruder 61 can be moistened with water or the like. As a result, friction between the sintering raw material and the intruding body 61 can be reduced, and adhesion of the sintering raw material to the intruding body 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.

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 intruding body 61 . A nozzle 52 is provided for each groove G, that is, for each intruding body 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 path. 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 groove G is formed in the raw material bed R on the pallet truck 14 by the outer peripheral portion 612 of the intruding body 61 . The intruder 61 enters the raw material bed R on the pallet truck 14 from its upstream end E1u, starts forming the groove G, and completes the formation of the groove G at the maximum width W1max. The pressing surface 651b of the pressing body 651 presses the surface of the raw material bed R at least in a range A11 from the upstream end E1u of the intruding body 61 to the maximum width W1max on both sides of the intruding body 61 (groove G). As a result, while the groove G is being formed in the raw material bed R by the intruder 61, the surface of the raw material bed R is pressed on both sides of the groove G that is being formed. Therefore, it is possible to prevent the sintering raw material from rising on both sides of the groove G. As a result, it becomes difficult for the sintering raw material to have a portion where the density of the particles is low, and the generation of return fines can be suppressed. As described above, according to the present embodiment, the grooves G are formed in the sintering raw material to reduce the airflow resistance of the sintering raw material and to suppress the generation of return ores.

In this embodiment, the pressing surface 651b extends further upstream than the upstream end E1u of the intruding body 61, and presses a range A12 of the surface of the raw material bed R on the upstream side from the upstream end E1u of the intruding body 61 as well. That is, the pressing surface 651b begins to press the surface of the raw material bed R before the intruder 61 enters the raw material bed R and starts forming the groove G. As shown in FIG. Therefore, it is possible to prevent the sintering raw material from rising on both sides of the groove G more reliably.

In this embodiment, the pressing body 651 can move up and down relative to the shaft member 62 and the intruding body 61 . Therefore, even if the layer thickness of the raw material bed R changes and the height of the surface of the raw material bed R changes, the pressing surface 651b follows the surface of the raw material bed R due to the weight of the pressing mechanism 65 itself. Therefore, the pressing surface 651b can reliably press the surface of the raw material bed R regardless of changes in the layer thickness of the raw material bed R.

As described above, when the intruders 61 and 610 are fixed while being inserted into the raw material bed R, the pressing surfaces 651b and 6510b are on the surface of the raw material bed R downstream of the downstream ends of the maximum width portions W1max and W1max. is preferably not pressed. Thereby, it is possible to prevent the completed groove G from collapsing due to the pressing force of the pressing surfaces 651b and 6510b.

In this embodiment, a peripheral surface 651c is provided around the pressing surface 651b. The peripheral surface 651c rises outward from the pressing surface 651b. Therefore, the edge of the lower surface of the pressing body 651 does not come into contact with the raw material bed R, and the surface of the raw material bed R can be prevented from being roughened.

In this embodiment, a groove G is 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.

8 to 10 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. 8 is a longitudinal sectional view of a sintered layer SLa formed by a sintering machine before the sintering machine 1 according to this embodiment. 9 and 10 are longitudinal sectional views of sintered layers SLb and SLc formed by the sintering machine 1 according to this embodiment. 9 shows the sintered layer SLb when the coolant supply device 50 does not supply the coolant, and FIG. 10 illustrates the sintered layer SLc when the coolant supply device 50 performs the coolant supply.

As shown in FIGS. 8 to 10, after the sintering material is ignited by the ignition furnace 30, the sintered layers SLa, SLb, and SLc are formed while the pallet truck 14 is traveling toward the ore discharge section 12. 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 5. did. FIG. 8 shows a longitudinal sectional view of the sintered layer SLa formed by the sintering machine proposed in Patent Document 5. 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. 8, 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, and the thickness of the combustion/melting zone increases. It was an operation that had to reduce the running speed and lower the production efficiency. In the sintered layer SLa shown in FIG. 8, 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 closed pore-generated portion drops thereafter, the ventilation resistance of the portion remains high. In FIG. 8, 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. 9 and 10, 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. 9, 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. 9, 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. 10, in the sintering machine 1 according to the present embodiment, the solid line indicates 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. 10, 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.

1: Sintering Machine 13: Endless Track 14: Pallet Truck 16: Firing Zone 17: Cooling Zone 30: Ignition Furnace 60: Grooving Device 61: Penetrating Body 651: Pressing Body 651b: Pressing Surface 651c: Peripheral Surface

Claims (6)

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 grooving device arranged upstream of the ignition furnace in the direction of travel of the pallet truck;
with
The groove forming device
an intruder that intrudes into the sintering raw material on the pallet truck to form a groove;
a pressing body including pressing surfaces disposed on both sides of the intruding body in the traveling direction and pressing the surface of the sintering raw material on the pallet truck;
has
The pressing surface extends at least from the upstream end of the intruder to the maximum width portion of the intruder having the maximum length in the width direction of the endless track in the running direction ,
The upstream end and the maximum width portion are the upstream end of the intruder and the maximum length of the intruder in the width direction in a cross section of the intruder cut along the surface of the sintering raw material. The sintering machine , which is the part that has . A sintering machine according to claim 1,
The sintering machine, wherein the pressing surface extends upstream of the upstream end of the intruder in the running direction. The sintering machine according to claim 1 or 2,
The sintering machine, wherein the pressing body is attached to the intruding body so as to be able to move up and down relative to the intruding body. The sintering machine according to any one of claims 1 to 3,
The intruder is fixed while being inserted into the sintering raw material on the pallet truck,
The sintering machine, wherein the position of the downstream end of the pressing surface coincides with the position of the downstream end of the maximum width portion in the traveling direction. The sintering machine according to any one of claims 1 to 4,
The pressing body further
A peripheral surface facing the sintering raw material on the pallet truck, provided around the pressing surface, and rising outward from the pressing surface;
Sintering machine, including. The sintering machine according to any one of claims 1 to 5,
The pallet truck is arranged in a firing zone for advancing the firing of the sintering raw material on the pallet truck, and downstream of the firing zone in the traveling direction to cool the sintering raw material fired in the firing zone. Cooling zone, to drive,
A sintering machine, wherein a coolant is injected into the grooves between the firing zone and the cooling zone.

Images