JP6357842B2 - Sinter ore manufacturing method - Google Patents

Description

  The present invention relates to a method for producing sintered ore.

As is well known, in the blast furnace method, it is desirable that the iron ore charged into the blast furnace is a sintered ore, which is currently widely practiced. As the quality of the sintered ore, an FeO component having properties that are difficult to reduce compared to other components is managed. In addition, FeO here refers to the whole substance used as Fe (II) ion of iron oxide, and does not refer only to FeO (wustite) in a narrow sense.
Since the high FeO component sintered ore has poor reducibility, there is a problem of increasing the reducing material ratio in the blast furnace. In particular, sintered ore with a concentration of FeO component of 10.0% by mass or more has a problem of deteriorating the reducing material ratio, so that the sintered ore with high FeO component is reduced so that the obtained sintered ore is less than this concentration. We try to avoid using raw materials as much as possible.

  However, in recent years, depletion of high-quality iron ore resources has become apparent, and new development of low-grade iron deposits with a low total iron (T.Fe) component has been promoted. When low-grade iron ore with low iron content is used in a blast furnace, the ratio of reducing material deteriorates. Therefore, in order to increase the quality of iron ore, the beneficiation processing of the mined iron ore is performed in advance. In the beneficiation process, in order to separate iron ore into gangue and iron oxide in units of particles, the iron ore is finely pulverized to 100 μm or less, and this is used using heavy liquid, surface active liquid, magnetic force, centrifugal force, etc. The method of separating is taken.

Magnetite ores are attracting attention because they can efficiently conduct magnetic ore as a beneficiation treatment. However, since the main composition of magnetite ore is composed of magnetite (FeO · Fe ₂ O ₃ ), the FeO component is as high as 20 to 30% by mass. Moreover, because it is a fine powder, it cannot be directly put into the blast furnace. For this reason, the method of using a magnetite-type ore as a raw material of the sintered ore manufacture for which a low FeO component is calculated | required has become a big subject.

In general, in the production of sintered ore, limestone and coke are added to and mixed with scales generated in various iron ores and steelworks, and further granulated to produce a blended raw material.
By charging this blended raw material into a sintered pallet, a packed layer having a layer thickness of about 500 mm is formed. Then, the surface of the packed bed is ignited by an ignition burner. The ignition time is about several tens of seconds, and the surface of the packed bed is heated to about 1300 ° C. After completion of ignition, sintering is started by sucking air in the atmosphere from the surface of the packed bed.
The air in the atmosphere is sucked by a wind box located at the bottom of the packed bed. Thereby, in the packed bed, air and the exhaust gas after sintering flow from the upper layer to the lower layer, and the combustion in the packed bed proceeds slowly from the upper layer to the lower layer. Sintering is completed in about 34 minutes.

In a commercial sinter production facility (dwyroid type (DL type) sintering machine), the sintering pallets are continuously connected. The sintering pallet charged with the blended raw material passes through the ignition furnace in the time until the sintering is completed, moves in the horizontal direction, and finally reaches the discharge end. Is discharged.
In this process, carbon in the coke is burned by air sucked from the surface of the packed bed. Thereby, the temperature of the combustion area | region of a packed bed rises, and sintering progresses by producing the sintering reaction of an iron ore and limestone. Sintered sintered ore structures are mainly composed of hematite (Fe ₂ O ₃ ), magnetite (FeO · Fe ₂ O ₃ ), calcium ferrite (CaO · Fe ₂ O ₃ ), oxalate slag (2FeO · SiO ₂ ). ₂ ).
The value of the FeO component in the sintered ore structure is greatly affected by the value of the FeO component of the blended raw material. For this reason, it is difficult to produce a sintered ore with a low FeO component from a blended raw material with a high FeO component unless the gas oxygen potential is significantly changed during the sintering process.

As a method for producing sintered ore, it is disclosed that fine limestone is used as a sintering raw material to reduce the granulated moisture than usual and to supply moisture to the surface of the sintered bed during the coke combustion reaction. (Patent Document 1). In Patent Document 1, coke carbon existing in a packed bed is reacted with supplied water to generate CO and H ₂ , thereby strengthening the reducing atmosphere and suppressing the generation of NOx.

  Further, it is disclosed that the air exhaust gas after sintering is supplied to the upper surface of the raw material layer and sucked downward to be sintered (Patent Document 2). In Patent Document 2, NOx generation is suppressed by sucking a low oxygen concentration gas during combustion of the middle layer. Further, by sucking the gas containing water vapor after the combustion of the fuel in the latter half of the sintering process is sucked, the cooling rate in the sintered layer is increased and the sintering rate is increased. Furthermore, by sucking gas containing environmental pollutants discharged in the second half close to the waste ore from the first half to the middle of the sintering process, environmental pollutants are adsorbed to the sinter cake and its generation is suppressed. .

JP-A-61-204346 JP-A-8-260062

However, the method of Patent Document 1 has a drawback of increasing the concentration of the FeO component in the sintered mineral product because the reducing atmosphere during firing is strengthened and the oxygen potential is lowered.
Moreover, in the method of Patent Document 2, coke combustion tends to be incomplete combustion because the sintered windbox exhaust gas having a low oxygen concentration is supplied to the upper surface of the raw material layer. Moreover, since the reducing atmosphere is strengthened, there is a drawback that the FeO concentration in the sintered ore product is increased.
For this reason, the techniques of Patent Documents 1 and 2 cannot be simply applied as a technique for producing a sintered ore having a low FeO component using a raw material containing a high FeO component.

  An object of the present invention is to provide a method for producing a sintered ore that can produce a sintered ore with a low FeO component at a high yield even when a blended raw material with a high FeO component is used.

The gist of the present invention is as follows.
(1) A method for producing a sintered ore having a FeO component of 10.0% by mass or less using a blended raw material having an FeO component of 10.0% by mass or more, and after sintering the surface of the packed bed, a sintering machine 5 kg / mixing raw material t or more on the surface of the packed bed only within the range of 30% on the ignition furnace outlet side of the sintered strand from the ignition furnace outlet to the end of the sintered strand. A method for producing sintered ore, characterized by spraying water vapor at a spraying amount of 18 kg / blending raw material t or less and sintering.
(2) Water vapor is sprayed on the surface of the packed bed only within a range of 20% on the ignition furnace outlet side from the ignition furnace outlet to the end of the sintered strand of the sintered strand (1) ) Sintered ore manufacturing method .

  According to the present invention, a sintered ore with a low FeO component can be produced at a high yield even when a high-FeO component blending raw material that contains a large amount of magnetite ore and scale is used.

The figure which shows the combustion behavior of the carbon and FeO component in sintering. It is a figure which shows a pan test apparatus and a sintering experiment procedure, FIG. 2 (A) shows ignition, FIG. 2 (B) shows water vapor | steam distribution, FIG. 2 (C) shows no water vapor | steam distribution. The figure which shows the relationship between water vapor | steam spraying time and the amount of product FeO. The figure which shows the relationship between the amount of water vapor | steam spraying, a product yield, and the amount of product FeO. The figure which shows the relationship between the mixing | blending raw material which varied the FeO component, and the amount of product FeO. The figure which shows the relationship between the mixing | blending raw material which changed the FeO component, and a product yield. The figure which shows the relationship between the mixing | blending raw material which varied the FeO component, and a sintering production rate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The method for producing sintered ore in the present embodiment is a method for producing a sintered ore having an FeO component of 10.0% by mass or less using a blended raw material having an FeO component of 10.0% by mass or more. After the surface ignition, the surface of the packed bed has water vapor within the range of 30% on the ignition furnace outlet side of the sintering strand from the ignition furnace outlet to the end of the sintered strand with respect to the total strand length of the sintering machine. It is characterized by spraying and sintering.

  As a blending raw material, a blending raw material having an FeO component of 10.0% by mass or more is used. Among these, it is preferable to mix 15.0% by mass or more of magnetite ore. A magnetite ore of 15.0% by mass or more has a feature that the particle size is finer than that of a scale and the like, and since it is porous, an oxidation reaction with water vapor occurs actively. In addition, it is particularly preferable to blend a high FeO raw material by magnetite-based pellet feed (PF) that is finer than a scale or the like because an oxidation reaction with water vapor occurs more actively.

In the present embodiment, sintering is performed by spraying water vapor on the surface of the packed bed in a predetermined region during sintering.
The air sucked during the sintering is preferably air in the atmosphere. For example, as described in Patent Document 2, if a part of the windbox exhaust gas after sintering is circulated and used, the oxygen concentration of the air to be sucked becomes low, which hinders the combustion of carbon and the combustion of FeO components. It becomes. Thereby, unburned carbon and a residual FeO component increase, and there exists a possibility that a sintered product yield may deteriorate.
It is water vapor that is mixed with the air sucked during sintering. This is because liquid water such as water mist requires a large amount of heat of vaporization to produce water vapor. In contrast, water vapor is optimal because it does not require heat of vaporization.

In the present embodiment, after surface ignition to the packed bed, within the range of 30% on the ignition furnace outlet side of the sintered strand from the ignition furnace outlet to the end of the sintered strand with respect to the total strand length of the sintering machine. Then, spray water vapor.
In general, in the industrial production of sintered ore, a DL type sintering machine in which sintering pallets are connected endlessly is widely used. This is a combination of sintered pallets in a batch system, and the sintering process is represented by the behavior in one sintered pallet. A packed bed is formed in the sintered pallet by charging the blended raw materials.
In the sintering process, combustion exhaust gas at 1300 ° C. is sucked from the surface of the packed bed for several tens of seconds. As a result, the carbon in the coke on the surface of the packed bed is ignited. Thereafter, by sucking normal temperature air, the coke is continuously burned and generates heat. This becomes a heat source for sintering. At the same time, the FeO component in the blended raw material is also combusted (oxidized) to Fe ₂ O ₃ , and the heat generated in this oxidation reaction may be a heat source.

In the sintering reaction process at an arbitrary point of the packed bed, the normal temperature raw material is heated by the high-temperature combustion exhaust gas supplied from above. As a result, the water first evaporates at 300 ° C. or lower, then the carbon burns and generates heat at 600 ° C. or higher, and finally the FeO component generates heat at 1200 ° C. or higher. And if the combustion amount of carbon and a FeO component falls, cooling will be started by the normal temperature air attracted | sucked from the surface.
In this sintering reaction process, carbon combustion occurs at approximately 600 ° C. or higher and a high combustion rate, while FeO component combustion occurs at a high temperature of 1200 ° C. or higher and at a very slow combustion rate. For this reason, almost no unburned carbon is produced, but a large amount of unburned FeO component (ie, product FeO) remains.
Reflecting these combustion behaviors, the combustion site in the height direction of the packed bed changes with the passage of time sequentially from the completion of ignition. That is, the combustion site proceeds from the upper layer where air and water vapor are sucked toward the lower layer of the suction outlet. Combustion is completed when the bottom floor layer is reached. In the case of a packed layer having a layer thickness of about 500 mm, the sintering is completed in about 34 minutes.

When the present inventors diligently investigated the difference in combustion behavior of carbon and FeO components in the packed bed, it was found that there is a difference as shown in FIG. In FIG. 1, the left side shows the carbon combustion front and the combustion front of the FeO component in the packed bed, and the right side shows the temperature distribution at the (A) position, (B) position, and (C) position in the packed bed. Yes.
In the combustion of carbon, since the combustion start temperature is a low temperature of 600 ° C. or higher and the combustion speed is high, as shown by the solid line on the left side of FIG. 1, the carbon combustion front descends at a high speed from the upper layer toward the lower layer. Have. Further, the amount of residual (unburned) carbon due to the combustion of carbon is small.
On the other hand, since the combustion start temperature is 1200 ° C. or higher and the combustion speed is slow and slow, the FeO component is burned at a slow speed from the upper layer toward the lower layer as shown by the broken line on the left side of FIG. It has the feature that the front line descends. And the amount of residual (unburned) FeO due to the combustion of this FeO component is also large.
That is, the rate of progress is different between the combustion front of carbon and the combustion front of the FeO component, and in the initial stage of the sintering process (combustion in the upper layer), the combustion reaction regions almost overlap, but in the middle stage (in the middle layer) It can be seen that there is a gradual shift in the combustion reaction area between the combustion and the later stage (combustion in the lower layer).
Therefore, by sucking water vapor H ₂ O together with oxygen (air) in the initial stage of the sintering process (combustion in the upper layer), both the carbon and FeO components cause an oxidation reaction at the same time, and the oxidation exothermic reaction is strengthened. The FeO component of the sintered ore structure can be lowered at a high temperature of 1200 ° C. or higher.

On the other hand, in the middle stage of the sintering process and the later stage of the sintering process, the combustion heat generation positions of the carbon and the FeO component are in a state of being separated. For this reason, even if an attempt is made to suck water vapor together with air and promote the combustion reaction of the FeO component in this state, the combustion of the FeO component does not occur, and the temperature rises as shown in the temperature distribution on the right side of FIG. On the contrary, the region of 1000 ° C. to 1200 ° C. expands. As a result, this leads to a decrease in productivity due to a delay in cooling of the sintered region of the packed bed and an increase in the product FeO due to obstruction of carbon combustion.
That is, the water vapor sucked from the surface of the packed bed first burns by the reaction shown in the following formula (1) in the region where the high-temperature FeO component located on the upper side burns, and then the carbon located on the lower side burns. Move to the area where it is H ₂ .
2FeO + H ₂ O → Fe ₂ O ₃ + H ₂ (1)
Since the reaction represented by the above formula (1) is a slight exothermic reaction, the reaction hardly causes a temperature change in the region where the FeO component is burning. However, H ₂ is supplied to the region where the carbon located on the lower side is burning. The supplied H ₂ generates heat due to combustion between the region where the FeO component is combusting and the region where the carbon is combusting while heading toward the region where the carbon is combusting ( 2H ₂ + 1 / 2O ₂ → H ₂ O). If it does so, since a comparatively low temperature will exist in a wide form, without a high temperature in a combustion area | region, it will result in the combustion of a FeO component being suppressed from the fall of combustion temperature.

Therefore, in order to cause the water vapor to be sucked together with air during the sintering process to burn the FeO component, the positional deviation between the carbon combustion region and the combustion region of the FeO component is small, and is limited to the initial stage (combustion in the upper layer). There is a need to. This initial stage corresponds to the strand position within the range of 20% to 30% from the ignition furnace exit side.
It should be noted that the spraying of water vapor from the position exceeding 30% to the end of the ore is not very effective in promoting the oxidation of the FeO component as described above, and the oxidation zone is widely dispersed and expanded, and conversely sintered. As a result, it takes time to cool the cake.
In addition, when water vapor is sprayed over the entire region of the strand, although it is improved in the initial stage (combustion in the upper layer), the adverse effect is significant in the intermediate stage (combustion in the middle layer) and late stage (combustion in the lower layer). As a result, the result is not improved overall.
Among these, it is preferable to carry out the steam spraying within the range of 20% on the ignition furnace outlet side from the ignition furnace outlet of the sintered strand to the end of the sintered strand. Furthermore, the range of 26% on the ignition furnace outlet side is particularly preferable.

The amount of water vapor sprayed is preferably 5 kg / raw material dry amount t or more and 18 kg / raw material dry amount t or less. If it is less than 5 kg / raw material dry weight t, the FeO component may not be sufficiently reduced. On the other hand, if it exceeds 18 kg / raw material dry weight t, the oxidation combustion of the FeO component becomes too active, and the oxygen concentration decreases. For this reason, carbon combustion is obstructed, and conversely, unburned carbon and residual FeO components increase, and the sintered product yield may deteriorate.
The spraying of water vapor may be carried out continuously or intermittently within the above range.

  Thus, in the sintered ore manufacturing method of this embodiment, a low FeO component of 10 mass% or less and a high yield sintered ore can be manufactured at a high production rate from a blended raw material of a high FeO component.

Next, the present invention will be described in more detail with reference to examples. In addition, this invention is not restrict | limited to the description content of these Examples at all.
(Sintering raw material)
The mixing ratio of the sintering raw materials used in the experiment is shown in Table 1 below. Formulation 1 is a raw material which made the FeO component 10% or less. Formulation 2 is a raw material in which a large amount of scale is blended and the FeO component is 10.5%. Formulation 3 is a raw material in which magnetite PF and scale are blended and the FeO component is 10.5%. Formulation 4 is a raw material in which magnetite PF is blended and the FeO component is 13.0%. Formulation 5 is a raw material in which magnetite PF is blended and the FeO component is 17.20%.

(Pot testing device)
The pot test apparatus and the sintering experiment procedure are shown in FIG. FIG. 2A shows ignition, FIG. 2B shows water vapor distribution, and FIG. 2C shows no water vapor distribution (only air suction). The pot test apparatus used was a small sintering pot testing apparatus capable of testing an inner diameter of 100 mm and a layer height of 500 mm, and a medium sintering pot testing apparatus capable of testing an inner diameter of 300 mm and a layer height of 500 mm.
The sintering pot 1 is formed in a cylindrical shape, and a grate 2 capable of aeration is provided on the inner bottom thereof. In addition, a suckable air box 3 is installed at the lower part of the sintering pot 1. An exhaust gas pipe 4 for exhausting the sucked gas is connected to the wind box 3. The exhaust gas pipe 4 is provided with a temperature sensor (not shown) for measuring the temperature of the sucked sintered exhaust gas. And the filling layer 5 is formed by charging a mixing raw material in the inside of the sintering pot 1. Note that air is sucked by the wind box 3 and the gas sucked from the exhaust gas pipe 4 is exhausted in any of ignition, steam spraying, and no steam spraying.
As shown in FIG. 2A, an ignition burner 6 is installed on the upper portion of the sintering pot 1 for ignition. In addition, when spraying water vapor, the ignition burner 6 is removed from the upper part of the sintering pot 1, and instead, as shown in FIG. Installed. A steam supply pipe 8 for supplying water vapor and an air supply pipe 9 for supplying air are connected to the water vapor spraying hood 7. In addition, when not spraying water vapor | steam, as shown in FIG.2 (C), nothing is especially installed in the upper part of the sintering pot 1 with the ignition burner 6, the food | hood 7 for water vapor | steam distribution, etc. As shown in FIG.

(Sintering experiment procedure)
2A to 2C show a procedure for a sintering experiment using a sintering pot test apparatus.
The blended raw materials were mixed for 4 minutes by a batch type cylindrical drum mixer having an inner diameter of 600 mm and a length of 800 mm, and water was added to granulate for 4 minutes.
The granulated blended raw material was charged into the sintering pot 1 shown in FIG. 2 in a dry amount (about 500 mm layer thickness) to form a packed bed 5 in the sintering pot 1.
After charging the compounding raw material into the sintering pot 1, as shown in FIG. 2A, an ignition burner 6 is installed at the upper part of the sintering pot 1, and the wind box 3 is installed at the lower part of the sintering pot 1. Then, the surface of the packed bed 5 was heated by the ignition burner 6 for 1 minute while sucking at 10 kPa.
After completion of the ignition, as shown in FIG. 2 (B), the ignition burner 6 was removed from the upper part of the sintering pot 1, and a water vapor spraying hood 7 was immediately installed. Then, by supplying water vapor from the water vapor supply pipe 8 and air from the air supply pipe 9 into the water vapor distribution hood 7, water vapor is applied to the surface of the packed bed 5, and air and A mixed gas of water vapor was sucked for a predetermined time.
After spraying the steam, as shown in FIG. 2C, the supply of steam is stopped, the steam spraying hood 7 is removed from the upper part of the sintering pot 1, and only air is sucked by suction by the wind box 3. Sintering was performed.
After the maximum temperature of the sintered exhaust gas was measured by a temperature sensor (not shown) installed in the exhaust gas pipe 4, the suction was stopped 3 minutes later, and the obtained sintered cake was allowed to cool naturally.
The cooled sintered cake is put into a drop test apparatus (not shown), dropped four times and pulverized, and then the pulverized product is classified with a 5 mm square sieve, and the product yield and FeO as a sintered mineral product above 5 mm are classified. Ingredient values were evaluated.

<Example 1>
Using the sintered raw material of compound 4 and a small sintering pot test apparatus, an experiment was conducted to confirm the effect due to the difference in the position of water vapor spraying.
Sintering is divided into three sections: the first period (0.3 to 8 minutes after completion of ignition), the middle period (8 to 20 minutes after completion of ignition) and the second period (20 to 30 minutes after completion of ignition). The sections for spraying water vapor were performed in the above three sections. The amount of water vapor sprayed was 17 kg / raw material dry amount t. In addition, an experiment was conducted in which a section for spraying water vapor was not provided. The experimental results are shown in FIG.
In addition, when the area | region which distributes water vapor | steam is made into the middle period, ignition shown in FIG. 2 (A), no water vapor | steam dispersion | distribution shown in FIG. 2 (C), water vapor | steam dispersion | distribution shown in FIG. 2 (B), FIG. ) In the order without spraying water vapor. Moreover, when the area | region which distributes water vapor | steam was made into the latter period area, it implemented in order of the ignition shown in FIG. 2 (A), the water vapor | steam dispersion | distribution shown in FIG. 2 (C), and the water vapor | steam dispersion | distribution shown in FIG. In the case where a section for spraying water vapor was not provided, the firing was performed in the order of ignition shown in FIG. 2 (A) and steam spraying shown in FIG. 2 (C).

The pan test is a test method capable of simulating the sintering phenomenon established in the JIS / ISO standard, although the sintering pallet does not move continuously like a commercial DL type sintering machine. In this case, the pan body corresponding to the pallet does not move, but the elapsed time from the start of ignition can be converted into the strand position using the following formula (F1).
Strand relative position X (%) = Elapsed time t from ignition start / Sintering completion time (F1)

Table 2 below shows the elapsed time from the start of ignition and the relative position of the strand when the time until the completion of sintering is 34 minutes.
In addition, the strand relative position shown in following Table 2 is a position in the elapsed time from the ignition start. For this reason, when calculating | requiring the strand relative position in the elapsed time after completion of ignition, it is necessary to subtract the strand relative position after the completion of ignition from the strand relative position calculated from the following formula (F1). .

  As shown in FIG. 3, the amount of FeO component decreased in all examples in which water vapor was sprayed, compared to the example in which water vapor was not sprayed. Moreover, when each example which sprayed water vapor | steam was compared, the result in which the amount of product FeO was reduced significantly about the example which water vapor sprinkled in the first term section was obtained. From this result, it was confirmed that the steam spraying is most effective when carried out in the first period of sintering.

<Example 2>
Using the sintering raw material of compound 4 and a small sintering pot test device, the sintering section for spraying steam is limited to the previous section (0.3 to 8 minutes after completion of ignition), and the effect due to the difference in spraying amount of steam An experiment was conducted to confirm. The amount of sprayed water vapor is shown in Table 3 below. The experimental results are shown in FIG.

  As shown in FIG. 4, the amount of product FeO increased and the product yield decreased since the amount of sprayed water exceeded 18 kg / raw material dry amount t. The reason is presumably that the unburned carbon and residual FeO components increased as a result of the instability of both combustions due to insufficient oxygen concentration to burn both carbon and FeO components. Further, it is presumed that the product yield is lowered due to the lowering of the combustion temperature, and the effect on the low FeO component is lost.

<Example 3>
Using the sintered raw materials of Formulations 1 to 5 and the medium-sized sintering pot test apparatus, an experiment was conducted to confirm the effect due to the difference in the sintered raw materials. The amount of water vapor spray is shown in Table 4 below. The experimental results are shown in FIGS.

As shown in FIG. 5, when using the sintering raw materials of the blends 2 to 5 in which the FeO component is blended in an amount of 10% by mass or more, the amount of FeO obtained from the sintered ore is a sintering method in which water vapor is not dispersed. Thus, the results corresponded to the amount of FeO component contained in the sintering raw material. On the other hand, it was confirmed that the amount of product FeO can be reduced to 10% by mass or less in the sintering method in which water vapor is dispersed.
Moreover, as shown in FIG.6 and FIG.7, the improvement of a product yield and a production rate can be confirmed by implementing water vapor | steam dispersion | distribution.
It should be noted that the high FeO component blending material (mixing 3 to blending 5) containing more magnetite PF is more porous than the high FeO component blending material (compounding 2) containing a lot of hematite PF and scale. It can be said that the combustion of the FeO component is promoted in the mineral, the product yield is high, and this is a desirable mode.

  DESCRIPTION OF SYMBOLS 1 ... Sintering pan, 2 ... Great, 3 ... Wind box, 4 ... Exhaust gas piping, 5 ... Packing layer, 6 ... Ignition burner, 7 ... Steam | dose for water vapor | steam spraying, 8 ... Steam supply pipe, 9 ... Air supply pipe.

Claims (2)

A method for producing a sintered ore having a FeO component of 10.0% by mass or less using a blended raw material having a FeO component of 10.0% by mass or more,
After surface ignition to the packed bed, the filling is performed only within the range of 30% on the ignition furnace outlet side of the sintering strand from the ignition furnace outlet to the end of the sintered strand with respect to the total strand length of the sintering machine. A method for producing a sintered ore, characterized in that the surface of the layer is sintered by spraying water vapor at a spraying amount of 5 kg / mixed raw material t or more and 18 kg / mixed raw material t or less.   The steam is sprayed on the surface of the packed bed only within a range of 20% on the ignition furnace outlet side from the ignition furnace outlet to the end of the sintered strand of the sintered strand. Sinter ore manufacturing method.

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