KR20180047213A - sintering apparatus and method for manufacturing sintered ore of using it - Google Patents

Abstract

Disclosed is a sintering apparatus comprising: a carriage loaded with a sintering material and being movable in a proceeding direction of a sintering process; an ignition furnace installed on a path of the carriage to shoot a flame toward a material layer loaded in the carriage; and a plurality of wind boxes arranged from a bottom of the ignition furnace to a sintering end point. A sintering section of the ignition furnace is divided into an initial part, an intermediate part and a terminal part in a moving direction of the carriage. A size of a passage, through which air flows, of the wind box installed to the initial part is smaller than that of a passage of the wind box installed to the intermediate and terminal parts. It is possible to reduce a flow rate of the air introducing into the wind boxes and the carriage in the initial part which performs ignition of the flame and sintering of an upper layer, relative to the intermediate and terminal parts, thereby preventing the upper layer from being cooled due to inflow of the air.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sintering apparatus,

More particularly, the present invention relates to a sintering apparatus capable of improving the production rate of sintered ores and a method of producing sintered ores by using the sintering apparatus.

The sinter ore used as a raw material in the blast furnace is produced by mixing iron ore and coal (or coke) as a heat source, burning the coal, and sintering the iron ore as the heat of combustion.

The method of producing the sintered ores is briefly described. First, the upper light stored in the upper light hopper and the compounding materials stored in the surge hopper are loaded on the truck and transported. At this time, a flame (that is, a flame) injected from the ignition furnace is ignited on the surface of the sintered raw material accommodated in the car, that is, the surface layer. The bogie that has passed through the ignition furnace is conveyed by the conveyor in the process direction, and the bogie passes through the upper side of the plurality of windboxes arranged in the process direction. A suction force is generated in the downward direction on the bogie passing through the upper side of the wind box and the flame ignited by the air outside the bogie is in the downward direction. At this time, the ignited flame reacts with the air introduced from the outside to cause a combustion reaction, and the temperature of the raw material layer around the flame rises to 1300 to 1400 ° C. As the temperature rises, a low melting point compound is formed due to the reaction of the iron ore and the additive, and a local melt is produced. As the melt is cooled again, the sintered ores are produced. Then, when the truck arrives at the windbox located at the end of the process, the flame reaches the bottom of the truck, at which time the sintering is complete and the above operations are continuously performed for a plurality of trucks.

On the other hand, as described above, the flame or heat is moved downward as the bogie having ignited the flame passes through the wind box as described above, and the sintered layer of the raw material layer is rapidly cooled by the air at room temperature, There is a problem that the temperature is lowered, and thus the raw material for sinter is shrunk and the air permeability is lowered. As a result, the upper layer, which is the upper region of the raw material layer, is insufficient in heat quantity and reaction time for sintering reaction, and unreacted sintered ores (that is, sintered ores where iron ores are not reacted) are generated in the upper layer, There is a problem that the recovery rate of the sintered ores increases.

Korean Patent Publication No. KR20020042893A

The present invention provides a sintering apparatus capable of improving the production rate of sintered ores and a method of producing sintered ores using the same.

The present invention provides a sintering apparatus capable of ensuring air permeability by preventing cooling and shrinkage of a raw material layer for sintering, and a method for manufacturing sintered ores using the sintering apparatus.

The sintering apparatus according to the present invention is a sintering apparatus capable of loading a raw material for sintering and capable of moving in the direction of sintering process; An ignition means provided on the route on which the bogie moves, for spraying a flame into the raw material layer charged in the bogie; And a plurality of windboxes arranged from the lower side to the sintering end point by the ignition,

The sintering section from the lower side of the ignition furnace to the sintering end point is divided into a front half portion, a middle half portion, and a rear half portion in a moving direction of the bogie, and a size of a passage through which the outside air sucked in each wind box installed in the front half portion moves, Which is smaller than the size of the passage of the wind box installed in the vehicle.

The plurality of windboxes provided in the first half are installed so that the size of the passageways decreases from the middle to the direction in which the ignition passages are located.

The inner diameter of each of the wind boxes installed in the first half is smaller than the inner diameter of the wind box installed in the middle half and the second half, and the plurality of wind boxes installed in the first half are smaller in size from the middle half to the direction in which the ignition path is located .

Wherein the pressure regulating member has an opening communicating with the passage of the wind box, and the size of the opening of each of the pressure regulating members is The size of the passageway of the wind box installed in the middle and the rear half is smaller than that of the wind box installed in the middle and the rear half, and the pressure regulating member is formed such that the inner diameter becomes smaller from the middle to the direction in which the ignition path is located.

And a pressure regulating member for regulating a size of a passage in the wind box, the pressure regulating member having an opening communicating with the passage of the wind box, Wherein the pressure regulating member is installed in a plurality of wind boxes installed in the front part, wherein the opening area of each of the plurality of pressure regulating members is equal to the size of the passages of the plurality of wind boxes provided in the middle and rear parts And the opening area is adjusted so as to become smaller from the middle portion toward the direction in which the ignition path is located.

The pressure regulating members are arranged to face each other and include a regulating member movable toward or away from each other.

The sizes of the passages of the plurality of wind boxes installed in the middle and the rear half are the same.

The method for producing sintered ores according to the present invention comprises the steps of charging a raw material for sinter as a moving bogie in a traveling direction of a sintering process; A step of igniting the flame on the raw material layer on which the sintering raw material is loaded by passing the bogie loaded with the raw material for sinter downward by ignition; And a step of moving the bogies with ignited flames to the upper side of the plurality of windboxes arranged from the lower side to the end point of the sintering process by the ignition and sucking the outside air into the bogie to proceed the sintering reaction,

The sintering section from the lower side to the sintering end point of the ignition to which the bogie travels is divided into a front half portion, a middle half portion and a rear half portion in the moving direction of the bogie, and when the bogie passes the front half portion, To be smaller than the amount of air flowing when passing through the middle and the latter half.

When the bogie is moved from the lower side of the ignition furnace, which is the start section of the first half, to the first half of the first half, the air volume is increased so as to move from the ignition position to the first half.

Wherein a negative pressure of each of a plurality of windboxes provided in the first half is smaller than a negative pressure of the plurality of windboxes installed in the middle half and the second half, And the air volume increases as the bogie moves from the ignition position to the end of the first half when the bogie passes through the first half of the bogie, Increase negative pressure.

Wherein a negative pressure of each of a plurality of windboxes provided in the first half is smaller than a negative pressure of a plurality of windboxes provided in the middle half and the second half, To the first half end point of the ignition passageway and to increase the negative pressure from the ignition passageway to the first half end point of the ignition passageway, A windbox with a large size is installed.

The negative pressures in the plurality of windboxes installed in the middle and the rear half are the same.

According to the embodiment of the present invention, the outside air moving passages in the plurality of windboxes located in the first half of the entire sintering section are made larger than those in the middle and rear half portions. In the first half section, the wind box is configured so that the passage becomes smaller toward the position by the ignition in which the flame is ignited from the middle half. Accordingly, in the first half where flame ignition and upper layer sintering are performed, the outside air volume entering through a plurality of wind boxes and bogies can be reduced compared to the conventional, middle, and late parts. Therefore, it is possible to prevent the upper layer portion from being cooled due to the inflow of a large amount of outside air in the front half portion, and the contraction of the sintering raw material layer due to cooling can be minimized or prevented. Therefore, the problem of reducing the air permeability due to shrinkage does not occur or is minimized, and the flame or the combustion zone can be stably moved, thereby reducing the total sintering time, thereby improving the production of sintered ores.

1 is a view showing a main part of a sintering apparatus according to an embodiment of the present invention
2 is a view for explaining a raw material layer in a truck
FIG. 3 is a view for explaining a change in the windbox inner diameter of the first half according to the first embodiment of the present invention; FIG.
4 is a view for explaining the change of the windbox inner diameter in the first half of the second embodiment of the present invention
5 is a view for explaining a change in the windbox inner diameter of the first half according to the third embodiment of the present invention;
FIG. 6 is a graph showing a negative pressure (mmAq) over time of sintering when sintering was carried out using a sintering apparatus having a wind box according to Examples and Comparative Examples of the present invention
FIG. 7 is a graph showing the negative pressure (mmAq), the exhaust gas temperature, and the temperature of the raw material layer with the lapse of sintering time when sintering was carried out using the sintering apparatus having the wind box according to the first to third comparative examples and the embodiment
8 is a graph showing the relationship between the combustion rate parameter and the combustion rate
9 is a graph showing the relationship between the position of the ignition source and the position of the light-exiting portion from 0 to 1/4 point corresponding to the first half, from the position corresponding to the ignition furnace to the light- Graph showing negative pressure up to
10 is a graph showing the relationship between the flow rate (m / s) in the entire sintering section and the flow rate of the sintering section ) In the graph

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. Wherein like reference numerals refer to like elements throughout.

1 is a view showing a main part of a sintering apparatus according to an embodiment of the present invention. Fig. 2 is a view for explaining a raw material layer in a car. FIG. 3 is a view for explaining a change in the windbox inner diameter of the first half according to the first embodiment of the present invention. 4 is a view for explaining the change of the windbox inner diameter in the first half of the second embodiment of the present invention. 5 is a view for explaining a variation of the windbox inner diameter of the first half according to the third embodiment of the present invention.

Referring to FIG. 1, a sintering apparatus according to an embodiment of the present invention includes a hopper 13 containing a sintering raw material, a plurality of bogies 30 charged in a sintering raw material and sequentially moving in the direction of the sintering process, A conveyor 40 for extending a plurality of bogies 30 and extending from the side of the hopper 13 on the upper side of the conveyor 40 for igniting the flame on the sintered raw material charged into the bogie 30, A plurality of windboxes 500 arranged side by side on a conveying path of a plurality of bogies 30 from the lower side of the conveyor 40 and sucking or sucking the outside air into the bogie, And a blower 70 connected to the plurality of windboxes 500 to allow the outside air to be sucked into the car 30.

The sintering apparatus also includes a dust collector 60 for collecting dust in the exhaust gas discharged through the wind box 500, and a storage bin for storing various raw materials (i.e., sintered raw materials) for producing sintered ores.

The raw material for sinter to be charged into the carriage 30 includes a raw material to be charged to the upper side of the upper light and a raw material to be initially charged into the carriage 30. The blending raw materials include binders containing carbon (C) such as Fe-containing iron ore, fractional coke and anthracite, and additives including limestone or quicklime. In addition, the compounding material may further include a by-product containing carbon or an iron source and carbon, and a raw material for controlling the basicity.

The storage bin stores the constituent materials of the above-mentioned ingredients, that is, iron ores, binders, by-products, additives, basicity control materials, etc., and these materials are moved to the granulator and mixed and assembled. As a matter of course, a mixing device for mixing the raw materials for mixing and a granulator for mixing them may be separately provided.

The hopper 13 includes a first hopper 14 in which the upper light is stored and a second hopper 15 in which the granulated product of the mixing raw material is stored. The first and second hoppers 14 and 15 are installed on the rear side of the igniter 20 on the basis of the traveling path of the bogie 30 from above the bogie 30.

The second hopper 15 is located in front of the first hopper 14 with respect to the movement path of the bogie 30 and charges the bogie material, that is, the assembly, into the bogie 30. The second hopper 15 uniformly loads the sintering raw material in the width direction of the truck 30 without segregation and segregation so that the sintering raw material flows from the lower part to the upper part in the depth direction (that is, And the grain size is segregated to be small.

The ignition furnace 20 is located in front of the second hopper 15 and supplies a sintering raw material to the bogie 30 to supply a flame to the surface layer of the raw material layer to be ignited.

The hopper 13, the upper side on which the ignition furnace 20 is located, and the upper side where the ignition furnace 20 is located, are provided to provide a space for forming the raw material layer, It is an open shape. At least a part of the ventilation bar (not shown) may be disposed on the carriage 30 so as to be removable from the raw material layer.

2, when the loading of the raw materials for sintering is completed in the bogie 30, the raw material layer has a lower layer portion L3, a lower layer portion L3, and a lower layer portion L3, An upper layer L1 extending from the intermediate layer L2 to the uppermost surface, and an upper layer L1 extending from the middle layer L2 to the uppermost surface. More specifically, the upper layer portion L1 means a portion 80 mm to 120 mm below the uppermost surface of the raw material layer, preferably a depth of 100 mm, and the lower region of the upper layer portion L1 corresponds to the middle layer portion L2, And the lower side of the portion L2 is the lower layer portion L3.

Hereinafter, a wind box according to the first and second embodiments of the present invention will be described with reference to Figs. 1 to 3. Fig.

Here, for convenience of explanation, a section in which a plurality of windboxes 500 are arranged in the moving path of the truck is referred to as a sintering section. In other words, sintering proceeds in the order of the upper layer L1, the middle layer L2 and the lower layer L3 in the order of the lower layer L1, the lower layer L2, and the lower layer L3, as the bogie moves from the ignition furnace 20 toward the light- do. Hereinafter, the sintering reaction of the upper part (L1) of the raw material layer is mainly performed in the first half of the sintering section and the sintering section in which the sintering reaction mainly occurs in the middle part (L2) The sintering zone is called the latter half. That is, the sintering section is divided into the first half, the middle half, and the second half from the ignition furnace 20 toward the light pipe portion.

The plurality of wind boxes 500 sucks the outside air into the carriage 30 and moves the ignited flame or heat caused by the movement of the carriage 30 downward. The plurality of windboxes 500 are arranged in a section between the light-splitting sections from the lower side of the ignition furnace 200.

The wind box 500 is in the shape of a cylinder having an upper side corresponding to the lower portion of the truck 30 and a lower side in which the blower 60 is positioned, The plurality of windboxes 500 are arranged so that a plurality of windboxes 500 are continuously arranged from a position corresponding to at least the ignition passages 20 to a position immediately before the light-exiting portion . A duct 80 is connected to each of the plurality of windboxes 500, and the pipe is connected to the dust collector 60 and the blower 70.

As described above, the wind box 500 has a cylindrical shape in which the direction opposite to the carriage 30 and the direction connecting with the duct 80 are open. Hereinafter, the openings in the direction in which the ship 30 is swinging in the windbox 500 are referred to as one side openings, and the openings in the direction to be connected to the ducts 80 are referred to as the other side openings. More specifically, one opening of the wind box 500 may be an upper opening and the other opening may be a lower opening.

In the embodiment of the present invention, as shown in FIG. 3, a plurality of windboxes 500 are arranged in a line from the position of the ignition passages 20 to just before the light-directing part. In the windbox, The size of the passage in the width direction of the wind box 500 installed in the middle and the rear half is smaller than that in the width direction. Here, the width direction size of the passage through which the outside air moves in the wind box 500 is referred to as an "inside diameter" since it is an inside diameter in other words. The inner diameter (WA1, WA2, WA3) of the installed wind box in the first half section is configured to be smaller than the inner diameter (WB, WC) of the wind box 500 installed in the middle and the rear half of the wind box . More specifically, the inner diameters WA, WA1, WA2, and WA3 of the plurality of windboxes 500 installed in the first half section are smaller than the inner diameters WB and WC of the plurality of windboxes 500 installed in the middle and rear half portions, respectively . In other words, the inner diameters WB and WC of the plurality of windboxes 500 installed in the middle and the rear half have the same size. As described above, the inner diameters WA1, WA2 and WA3 ).

The sintering in the bogie 30 starts from the position of the ignition furnace 20 where the flame is ignited, and the first windbox 500 is usually installed on the lower side of the ignition furnace 20. If the amount of air to be sucked into the wind box 500 installed at the lower side of the ignition passages 20 is large when the flame is injected into the upper portion L1 of the blend material in the passageway passing the lower side of the ignition pass 20, L1 may be cooled, and thus the flame ignition may be difficult or even if ignition occurs, the upper layer may be cooled to lower the breathability. Therefore, in the embodiment of the present invention, the beginning of the first half of the sintering section corresponds to at least the position corresponding to the ignition furnace 20, and the inner diameter of the sintering section increases as the distance from the windbox 500, (WA1 < WA2 < WA3 ...). That is, the inner diameters WA, WA1, WA2, and WA3 of the plurality of wind boxes 500 provided in the front portion are smaller than the inner diameters WB and WC of the middle and rear portions (WA <WB, WC) (WA1 < WA2 < WA3 ...) from the lower side toward the middle portion. At this time, as shown in FIG. 3, the inner diameters of all of the plurality of wind boxes provided in the front portion are made different from each other, and the inner diameter gradually increases from the ignition furnace toward the middle portion (WA1 <WA2 <WA3 ...). As another example, the inner diameters of the plurality of continuously arranged windboxes may be the same, and the inner diameter of the windbox may gradually increase from the ignition furnace toward the middle portion.

 When the inner diameter WA of the plurality of windboxes 500 in the front portion is smaller than the inner diameters WB and WC of the windbox 500 installed in the middle and rear portions of the windbox 500, The negative pressure is smaller than that in the middle and the latter half. Accordingly, the blowing amount of the outside air sucked into the wind box 500 in the first half portion is smaller than that in the middle half portion and the second half portion, which is smaller than in the prior art. Therefore, the air blowing amount of the outside air sucked into the carriage 30 in the first half of the sintering period can be reduced, and the cooling of the upper layer can be prevented by the excess blowing amount, thereby preventing the blending material of the upper layer from shrinking. Furthermore, since the phenomenon of reducing the air permeability due to the shrinkage of the blended raw material can be minimized or prevented, the sintering speed can be improved as compared with the conventional method.

Since the cooling of the upper layer portion L1 is reduced, the combustion zone in the upper layer portion L1 in which the flame is ignited can be stably secured, thereby improving the sintering speed. Since the plurality of windboxes 500 installed in the sintering section are operated by one duct 80 and the blower 70, the air volume in the middle part increases due to the increase in resistance due to the decrease in the negative pressure in the first half, .

The material layer in the first half, that is, the upper half is located on the upper side of the middle and lower half, and the area exposed to the outside is large. Therefore, the cooling degree of the upper layer portion L1 tends to increase as the air flow rate of the outside air increases. However, since the middle layer portion L2 is separated from the outside or blocked, the combustion rate increases as the air volume of the outside air to be inhaled increases. Therefore, it is necessary to reduce the air volume in order to prevent the cooling in the first half and to stabilize the combustion zone, and to increase the air volume in the middle half and the latter half in order to improve the combustion rate.

In the above-described first embodiment, the inner diameter of the wind box 500 itself is reduced. However, the inner diameter of the wind box 500 is not limited to this, A pressure regulating member 610 may be installed to regulate the width direction size of the passage through which the ambient air moves in a certain section of the housing 500. That is, the pressure regulating member 610 is installed at any position of the wind box 500, and the section in which the pressure regulating member 610 is installed, compared to the section where the pressure regulating member 610 is not provided, So that the size of the passage through which the outside air can pass by the pressure regulating member 610 is reduced.

The pressure regulating member 610 may be of a hollow shape having an opening through which the outside air can pass, as shown in Fig. For example, the pressure regulating member 610 may be an orifice or a damper. A plurality of windboxes 500 installed in the first half, the middle half, and the second half have the same inner diameters (WA = WB = WC ), And a pressure regulating member 610 is installed only in a plurality of wind boxes 500 installed in the first half. The sizes WP of the respective opening portions of the pressure regulating members 610 provided in the plurality of wind boxes 500 of the front portion are determined by the inner diameters WB and WC of the wind box installed in the middle and rear portions, .

The size of the opening of the pressure regulating member 610 tends to increase as the pressure regulating member 610 provided in each of the plurality of wind boxes 500 installed in the front part approaches from the lower side to the middle part of the ignition path 20 WP1 < WP2 < WP3 ...). At this time, the size of each opening of the plurality of pressure regulating members provided at the front portion may be different from each other, and the size of the opening may be gradually increased from the ignition furnaces WP1, WP2, and WP3 toward the middle portion (WP1 <WP2 <WP3 ...). As another example, the opening size of the pressure regulating member 610 may be set so as to gradually increase from the ignition furnace 20 to the middle portion while keeping the opening sizes of the plurality of continuously arranged pressure regulating members 610 the same have.

In the above description, the pressure regulating member 610 having different opening sizes is installed in the plurality of wind boxes 500 of the front part.

However, the present invention is not limited thereto, and a pressure regulating member 610 capable of adjusting the opening size can be provided as in the third embodiment shown in Fig. The same pressure regulating member 610 is provided in each of the plurality of windboxes 500 in the front part so as to increase the size of the opening, that is, the open area, from the lower side to the mid- The size of the opening of the member 610 is adjusted (WP1 <WP2 <WP3 <WP4 ...).

The pressure regulating member 610 capable of adjusting the opening area may be, for example, a shutter structure capable of adjusting the opening inner diameter through sliding. That is, as shown in FIG. 5, the pressure regulating member 610 is fixed to the wind box 500 and includes a fixing member 611 having a hollow shape with an opening at its center, And a pair of regulating members 612 connected to the regulating member 611. The pair of regulating members 612 can move toward or away from each other, thereby adjusting the opening areas (WP1, WP2, WP3) of the pressure regulating member 610.

According to the embodiments of the present invention as described above, the negative pressure in the front half portion is smaller than the negative pressure in the middle half portion and the rear half portion by adjusting the size of the inner passage of the plurality of windboxes 500 installed in the front half portion. Accordingly, the blowing amount of the outside air flowing into the plurality of windboxes 500 of the front part is smaller than that of the conventional one, and is smaller than the blowing amount blown into the windbox 500 of the middle and rear half parts. Also, in the first half of the sintering, the size of the inner passage of the lower wind box 500 is larger than that of the other wind boxes due to the ignition of the flame, and as it approaches the ignition furnace from the position adjacent to the middle portion, Allow passage to increase in size.

Therefore, in the first half of the sintering section, the negative pressure of the wind box 500 installed at the point where the flame is ignited or in the section where the sintering is started after the flame is ignited is larger than the other sections. Therefore, the amount of outside air blown into the wind box 500 in which the flame is ignited is smaller than in the other wind boxes 500. Accordingly, it is possible to prevent the upper layer from being cooled by excessive air blowing amount in the early stage of the sintering when the flame is ignited or after the flame is ignited, thereby minimizing or preventing the decrease in air permeability due to shrinkage of the raw material mixture have. Thus, it is possible to reduce the burning speed and the sintering speed reduction due to the lowering of the air permeability, so that the burning speed and the total sintering speed can be improved as compared with the prior art, and the production rate of the sintered ores can be improved.

FIG. 6 is a graph showing the negative pressure (mmAq) over time of sintering when sintering was carried out using a sintering apparatus having a wind box according to Examples and Comparative Examples of the present invention. Here, in the embodiment, the passage of each of the plurality of windboxes 500 installed in the first half of the sintering section is smaller than the passage of the windbox 500 installed in the middle and rear half portions, and as the ignition passages approach the mid- So that the passage of the sintered body is reduced. The comparative example is a result of sintering in the same manner, or at least in the windbox passage provided in the first half and the middle half of the entire sintering section.

Referring to FIG. 6, in the comparative example, it can be seen that as soon as the sintering process is started, the negative pressure increases sharply to about 1900 mmAq. In the comparative example, the bobbin moves to the windbox position, It can be expected that the amount of outside air blown into the wind boxes of the front part rapidly increases due to the negative pressure in the wind box which has risen sharply. When such a large amount of foreign matter is sucked, the sintered layer, that is, the upper layer, which is sintered in the first half section, is cooled, so that the sintering temperature is not reached and sintering is not performed or the sintering speed is slow. In addition, the upper raw material mixture shrinks by cooling in the upper layer, whereas the comparative example shrinks by 3.3%. This causes deterioration of air permeability and consequent hindrance of movement of the combustion zone, which causes reduction of the sintering speed.

On the other hand, in the case of the example, it can be seen that the negative pressure gradually increases until 10 minutes after the start of the sintering process and is maintained. In this case, the sintering section before 10 minutes is the first half section having the smaller inner diameter than the middle half and the latter half section, and the negative pressure is smaller than that of the comparative example in the first half section (10 minutes before section). From these experimental results, it can be seen that the passages of the windbox 500 in the first half are reduced in the middle and the second half, and the passages in the plurality of windboxes 500 installed in the first half are made smaller as they are further away from the middle, Can be confirmed. As a result of confirming whether or not the upper layer was shrunk, the upper layer was not shrunk in the examples.

Through this experiment, it can be confirmed that the pressure increase rate of the negative pressure affects the contraction of the sinter raw material.

FIG. 7 is a graph showing the results of the negative pressure (mmAq), the exhaust gas temperature, and the temperature of the raw material layer with the elapse of sintering time when sintering was performed using the sintering apparatus having the wind box according to the first to third comparative examples and the example to be. 6B is a second comparative example, FIG. 6C is a third comparative example, and FIG. 6C is an example. The pressure, sintering completion point (BTP) time and sintering completion point The temperatures are shown in Tables 1 to 4.

division (Ignition -1000 mmAq)
-1700 mmAq BTP Time (min) 39.4 BTP temperature (캜) 313.9

division (Ignition -1000 mmAq)
-1900 mmAq BTP Time (min) 38.4 BTP temperature (캜) 364.5

division -1900mmAq from ignition BTP Time (min) 40.5 BTP temperature (캜) 463.4

division (Ignition -1000 mmAq), then elevated to -1900 mmAq for 10 minutes BTP Time (min) 37.3 BTP temperature (캜) 418.9

Comparing the first comparative example and the second comparative example with reference to Tables 1 and 2 and Figs. 6A and 6B, it is understood that the negative pressure is -1900 mmAq as compared with the first comparative example in which the negative pressure immediately after ignition is -1700 mmAq The sintering termination time of the second comparative example which is larger is decreased. However, in the case of the third comparative example in which the negative pressure was increased to -1900 mmAq from the ignition, it can be seen that the sintering time increased by 2.6% as compared with the second comparative example. From these results, it can be seen that, in order to reduce the sintering time, a low negative pressure condition is required at the time of ignition.

In the case of the embodiment, although the burning rate in the upper layer portion is slow, the combustion layer is stably formed, and the sintering speed in the second half is increased. Thus, it can be confirmed that the total sintering time is faster than that in the first to third comparative examples. Therefore, it has been concluded that the ignition of the flame is basically carried out therefrom, and the negative pressure is required to be reduced in the first half where the sintering of the upper layer proceeds, and the negative pressure control to gradually increase the negative pressure.

The sintering speed is related to the combustion rate of the blend material, that is, the coal, since the sintering speed is the movement of the combustion zone, that is, the coal is burned from the top to the bottom. The burning rate (R ^* _C ) of coal is as follows.

R ^* _C : Coal burning rate (kg / m ³ s)

ρ _s : solid upper layer apparent density (kg / m ³ )

Y _C : Mass ratio of carbon in solid bed (kg / kg)

K ^* _C : Coke burning rate coefficient (m / s)

X _O2 : Oxygen mass ratio in gas (kg / kg)

ρ _c : Coke apparent density (kg / m ³ )

d _c : Coke average particle size (m)

The coke burning rate coefficient (K ^* _C ) is as follows.

k _pc : Coke combustion reaction rate coefficient (m / s)

k _mc Coke burning mass transfer coefficient (m / s)

The coke combustion reaction rate coefficient (k _pc ) is as follows.

T _S : Solid phase temperature (K)

The coke combustion mass transfer coefficient (k _mc ) is as follows.

D _O2-C : oxygen diffusion coefficient in coke (m ² / s)

Sc: Schmidt number

Re: Reynolds number

ε _b : high upper layer porosity

d _e : solid-phase average particle size (m)

Here, the Reynolds number Re and the Schmidt number Sc are as follows.

v _g : gas velocity (m / s)

μ _g : Gas viscosity (kg / ms)

ρ _g : gas density (kg / m ³ )

ρ _g : gas density (kg / m ³ )

D _O2-N2 : oxygen diffusion coefficient in air (m ² / s)

T _g : gas temperature (K)

8 is a graph showing the relationship between the combustion rate parameter and the combustion rate.

The factors influencing the burning rate of the coal, that is, the sintering raw material layer, are the solid phase temperature (mixing material temperature), the oxygen concentration, the coal content, the gas velocity, the gas density and the coal particle size. As a result, the burning rate was affected more by the solid-state temperature than by the gas velocity (gas flow rate). As a result, it can be seen that the burning rate increases when the negative pressure in the first half of the sintering stage is stably maintained and the temperature is secured.

9 is a graph showing the relationship between the position of the ignition source and the position of the light-exiting portion from 0 to 1/4 point corresponding to the first half, from the position corresponding to the ignition furnace to the light- In the case of the negative pressure.

 In Fig. 9, the inner diameters of the plurality of windboxes are smaller than the inner diameters of the windboxes installed in the middle and the rear half, respectively, and the inner diameter of the windbox is increased from the zero point to the quarter point from the lower side by ignition. The inner diameters of the plurality of wind boxes are the same up to the 1/4 section, and the inner diameters thereof are larger than those of the embodiment.

Referring to FIG. 9, the negative pressure tends to increase as the sintering progresses from the zero point in both Comparative Examples and Examples. However, in the case of the comparative example, the negative pressure is about 1300 mmAq in the first half of the entire 1/4 section, and then rapidly increases to 2000 mmAq. This is because the inner diameter of the wind box is all the same, its inner diameter is large, and the blowing amount of the outside air is large. On the other hand, in the case of the embodiment, the negative pressure is gradually increased as compared with the comparative example.

10 is a graph showing the relationship between the flow rate (m / s) in the entire sintering section and the flow rate of the sintering section ), Respectively.

In the embodiment of Fig. 10, the inner diameters of the plurality of windboxes provided in the first half of the sintering section are smaller than the inner diameters of the windboxes installed in the middle and rear halves, respectively, . The comparative example is a result of sintering in which the windbox inner diameters of the entire sintering section are the same or at least the windbox inner diameters provided in the first half and the middle half are the same.

Referring to FIG. 10, the flow rate at which the outside air of the embodiment enters the wind box up to the mid-sintering portion is larger than that of the comparative example. This is because the inner diameter of the wind box in the first half is smaller than that in the middle half and the latter half, so that the negative pressure is small and the air blowing amount of the outside air is small. Therefore, compared to the comparative example, the shrinkage of the raw material layer does not occur or is minimized compared with the comparative example, so that the airtightness is better than that of the comparative example, and the heat is uniformly transferred or the flame or the combustion zone is easily moved. The amount of time it takes to complete the process is reduced.

500: Wind Box 600: pressure regulating member

Claims (12)

A bogie capable of charging raw materials for sintering and capable of moving in the direction of the sintering process;
An ignition means provided on the route on which the bogie moves, for spraying a flame into the raw material layer charged in the bogie;
A plurality of windboxes arranged from the lower side to the sintering end point by the ignition;
Lt; / RTI &gt;
The sintering section from the lower side of the ignition furnace to the sintering end point is divided into a front half portion, a middle half portion and a rear half portion in the traveling direction of the bogie,
Wherein a size of the passage through which the outside air sucked in each of the wind boxes installed in the first half is smaller than a size of the passage of the wind box installed in the middle half and the second half. The method according to claim 1,
Wherein the plurality of windboxes provided in the first half are arranged such that the size of the passages decreases from the middle to the direction in which the ignition passages are located. The method of claim 2,
The inner diameters of the windboxes provided in the first half are smaller than the inner diameters of the windboxes installed in the middle half and the second half,
Wherein a plurality of windboxes provided in the first half are arranged such that a size of an inner diameter decreases from a midpoint toward a direction in which the ignition path is located. The method of claim 2,
And a pressure regulating member for regulating the size of the inner passage in each of the wind boxes installed in the front part,
The pressure regulating member having an opening communicating with the passage of the windbox,
The size of the opening of each of the pressure regulating members is smaller than the size of the passage of the wind box installed in the middle and rear portions,
Wherein the pressure regulating member is formed such that the inner diameter becomes smaller from the middle portion toward the direction in which the ignition path is located. The method of claim 2,
And a pressure regulating member for regulating a size of the passage in the wind box inside each of the plurality of wind boxes installed in the first half,
The pressure regulating member has an opening communicating with the passage of the wind box, the size of the opening area being adjustable,
Wherein the pressure regulating member is installed in a plurality of wind boxes installed in the first half,
The opening area of each of the plurality of pressure regulating members is smaller than the size of the passages of the plurality of wind boxes provided in the middle and the rear half,
And the opening area is adjusted so as to decrease toward the direction in which the ignition path is located from the middle portion. The method of claim 5,
Wherein the pressure regulating members are arranged to face each other and are movable toward or away from each other. The method according to any one of claims 1 to 6,
And the sizes of the passages of the plurality of wind boxes installed in the middle and the rear half are mutually the same. A process of charging the raw material for sinter with a moving carriage in the direction of the sintering process;
A step of igniting the flame on the raw material layer on which the sintering raw material is loaded by passing the bogie loaded with the raw material for sinter downward by ignition; And
Moving the flame-ignited ladle to the upper side of the plurality of windboxes arranged from the lower side to the end point of the sintering process by the ignition, and performing the sintering reaction while sucking the outside air into the ladle;
/ RTI &gt;
The sintering section from the lower side to the sintering end point of the ignition movement of the bogie is divided into the first half, the middle half and the second half in the moving direction of the bogie,
Wherein the air flow amount of the outside air flowing into the truck when passing through the front part is smaller than the air flow amount flowing when the outside air passes through the middle part and the rear part. The method of claim 8,
And adjusting the amount of wind to be increased as the motor moves from the position of the ignition to the direction of the end of the first half when the bogie is moved from the lower side of the ignition furnace to the first half of the starting position of the first half. The method of claim 9,
The amount of air flowing when the bogie passes through the first half is smaller than the amount of air flowing when passing through the middle half and the second half,
The negative pressure of each of the plurality of windboxes provided in the first half is made smaller than the negative pressure of the plurality of windboxes provided in the middle half and the second half,
When the bogie passes through the first half, the air amount increases as the bogie moves from the ignition position toward the first half end point,
And increasing the negative pressure from the ignition furnace toward the end of the first half portion. The method of claim 9,
The negative pressure of each of the plurality of windboxes provided in the first half is made smaller than the negative pressure of the plurality of windboxes provided in the middle half and the second half,
Wherein a size of a passage through which the outside air sucked by each of the plurality of windboxes installed in the first half is smaller than a size of a passage of a plurality of windboxes provided in the middle and rear half,
In order to increase the negative pressure from the ignition passage toward the end of the first half portion,
And a wind box having a large passage size from the position of the ignition to the end of the first half. The method according to any one of claims 9 to 11,
Wherein a plurality of wind boxes installed in the middle and the rear half have the same negative pressure.

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