JP2000096154A - Method for compounding superfine coke to sintered raw material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for compounding superfine coke with sintered raw material which makes it possible to utilize the superfine coke recovered when collecting dust for carbonaceous material for production of sintered ore. SOLUTION: The iron ore powders for production of the sintered ore is prepared by piling many brands of the iron ore powders in multiple layers on a yard 1 of a rectangular shape in its base surface, feeding the iron ore powders by a reclaimer to a direction orthogonal with the axis of the rectangular shape and uniformly mixing these powders. At this time, the superfine coke 1 is first moistened and thereafter the layers of a uniform thickness are formed on the ground surface of the yard and the iron ore powders are successively stacked thereon so as to cover the superfine coke layers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mixing ultra-fine coke into a sintering raw material, and more particularly, to a method for baking solid sintering raw materials such as iron ore powder and limestone, to use ultra-fine coke which could not be used before. This is a technology that can be used.

[0002]

2. Description of the Related Art In order to efficiently produce pig iron in a blast furnace, a massive iron source is required to secure air permeability in the furnace.
Conventionally, as a massive iron source, from the viewpoint of effective use of iron ore, powdery iron ore is mixed with a slag-making agent such as limestone or a carbonaceous material and baked to produce an artificial ore called a so-called sinter. And
It is used. Generally, as the carbonaceous material, coke breeze sized to about -10 mm (for example, under a sieve of a blast furnace coke) is mainly used, and imported anthracite is pulverized and used for a shortage. Then, these coke breeze and anthracite are stored in a carbon material hopper 14 different from other sintering raw materials as shown in FIG. It is mixed with other sintering raw materials only in the step of mixing with each other (usually using a mixer 16).

[0003] Incidentally, dust is always generated when coke is conveyed or handled in a steelworks, but dust is collected in order to maintain a good working environment. When this dust collection is of a dry type, usually, a large amount of ultrafine coke having a particle size of 10 μm or less is recovered. Also, in the production of coke, if a dry-type fire extinguishing system for performing cooling in a dry manner, that is, a so-called CDQ (Coke Dry Queuer) is used, a large amount of ultrafine coke is similarly recovered. Therefore, the recovered fine coke has a very high carbon content, and has been marketed as it is as a raw material for a carbon electrode.

However, these ultra-fine coke powders
Currently, the cost of logistics soars, and it is considered that it is most economically effective to use it in the steelworks where it originated. I didn't.

[0005]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention provides a method for producing ultra-fine coke as a raw material for sintering, which makes it possible to use fine coke collected at the time of dust collection as a carbon material for sinter production. It is intended to provide a compounding method.

[0006]

Means for Solving the Problems In order to achieve the above object, the inventor of the present invention has studied diligently in controlling dust generation during handling of ultrafine coke, and has conducted an ore reduction of iron ore powder for sintering.
The idea was to lay the floor immediately before bedding (a technique of mixing and ore powders of different brands in the yard in layers and cutting them out in a direction perpendicular to the longitudinal direction to mix and ore each ore powder) and cover the ore from above. did. This is because not only the generation of dust can be suppressed but also the use of a reclaimer (ore cutting means) at the time of cutting can evenly distribute the carbonaceous material in the cut iron ore powder for sintering.

That is, according to the present invention, iron ore powders of various brands are piled up in layers on a rectangular yard having a bottom surface, cut out by a reclaimer in a direction perpendicular to the rectangular axis, and uniformly mixed to produce a sintered ore. When preparing iron ore powder for
First, after the ultra-fine coke is moistened, a layer having a uniform thickness is formed on the ground of the yard, and iron ore powder is sequentially stacked thereon to completely cover the ultra-fine coke layer. This is a method of blending the ultrafine coke into the raw material for sintering. Further, the present invention provides a sintering raw material for ultra-fine coke characterized by forming a layer of uniform thickness with wet ultra-fine coke on a previously stacked iron ore powder layer instead of on the ground of the yard. It is a method of blending into.

[0008] Further, the present invention provides a method for spraying said wetness and / or
Alternatively, the present invention is also a method for blending ultrafine coke into a sintering raw material, wherein the water content of ultrafine coke is constantly maintained in a range of 12 to 18% by weight by submerging or spraying.

According to the present invention, a large amount of ultra-fine coke is not dissipated, and it is possible to mix the coke into the sintering raw material in advance as a carbon material. As a result, ultrafine coke, which has not been used conventionally, can be processed in the same steel mill, and a great economic effect can be obtained.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

First, ultrafine coke 2 collected by dust collection or the like
Is stored in a tank truck 22 and transported. Then, the ultrafine coke is once dispensed to the tank 23 in a state where the hose 23 of the truck 22 is submerged in the water of the water reservoir 21. In this submerging process, the ultrafine coke is made to be in a wet state, and a treatment without scattering by wind or the like is performed. afterwards,
The ultrafine coke from the water storage tank 21 is temporarily placed in, for example, a coal yard 1 as shown in the plan view of FIG. In this coal yard, depending on the dry condition during temporary storage,
Watering is performed with the watering vehicle 3 or the like to maintain a wet state. The humidified ultrafine coke 2 is transported to an or-bed ore yard (hereinafter simply referred to as a yard) 5 by a dump car or the like (not shown), as shown in the plan view of FIG. Then, the yard 5 is laid on the floor using a rake 7 or the like so as to have a uniform thickness in the longitudinal direction. Note that the yard 5 often has a substantially rectangular bottom surface.

Next, the ordinary iron ore powder 8 is stacked on the two layers of the ultra-fine coke laid on the floor with a stacker (ore stacking means (not shown)) or the like so as to completely cover it (FIG. 1). (C)). As a result, the mountain (usually referred to as a bed) 9 has a substantially triangular prism-like shape.

Then, from the bed 9 of the finally formed iron ore powder layer or the like, a direction perpendicular to the longitudinal direction of the rectangle is indicated by the reclaimer (indicated by an arrow in FIG. 2B).
Then, iron ore powder 8 and the like are cut out. As a result, a uniform amount of the ultrafine coke 2 is contained in each iron ore powder 8 for each cut. That is, the ultrafine coke 2 was mixed with the sintering raw material.

In the present invention, the ultrafine coke 2 is positioned as a floor in the lowermost layer. However, according to a subsequent study by the inventor, it has been found that the same effect can be obtained even if the ultrafine coke 2 is not used as the lowermost layer. That is, a uniform thickness layer of the ultrafine coke 2 may be formed between the eight iron ore powder layers.

By the way, in making the present invention, the most troublesome thing is keeping the ultra fine coke 2 wet. Typically, the amount of bed 9 of iron ore powder 8 is of the order of 80,000 tonnes, so that it can be used in the same sintering machine for days to tens of days. On the other hand, to produce sinter of stable quality,
It is desirable that the quality (chemical composition, particle size) of the iron ore powder 8 cut out from the bed 9 is uniform. Accordingly, this time, the carbon material is first compounded in the bed 9, but in this case, it is desired that a certain amount of the carbon material is mixed uniformly.

However, the collection amount of the ultrafine coke 2 in the plant is about 100 tons on average per day, and in order to form the 80,000 ton bed 9 with the carbon material content of 0.6% by weight, the ultrafine coke 2 is required. Coke 2 needs to be stockpiled for several days. In the above example, the stockpiling is performed by temporary storage in the coal yard 1. Therefore, it is necessary to maintain the ultrafine coke 2 without scattering during the temporary placement. Further, if necessary, it is necessary to move to the bed 9 and immediately form a layer having a uniform thickness. In order to respond to the request, the inventor conducted intensive research and found a measure to sprinkle water on the ultrafine coke 2 during the temporary storage period and to constantly maintain the water content at 12 to 18% by weight. Then, this wetness management is also added to the present invention. If the water content exceeds 18% by weight, the slurry is in a slurry state, so it is difficult to stretch it to a uniform thickness.
If the content is less than 2% by weight, scattering cannot be prevented under normal weather. Although the temporary storage location is described as a coal yard, the ore bedding yard 5 is shown in FIG.
It is a matter of course that the water reservoir 21 shown in (a) may be arranged, and the ore bedding yard 5 may be immediately piled up to perform wetness management. Further, instead of the submerging treatment, the wet state may be achieved by spraying water.

[0017]

EXAMPLES In order to confirm the effects of the present invention, a sintered ore was produced using iron ore powder 8 containing ultrafine coke 2 obtained as described above. That is, ordinary sintering operation was performed using the sintering machine and the hoppers 10, 11, 12, and 13 for the respective sintering raw materials shown in FIG. The sintering machine 1
The sample No. 7 was a Dwight Lloyd type having an effective area of 400 m ³ , and was operated under the conditions of a raw material packed layer thickness of 560 mm and a pallet speed of 2.5 m / min.

Table 1 shows the types and mixing ratios of all the sintering raw materials charged in the hopper. With the compounding method according to the present invention alone, the amount of carbon material as a whole of the sintering raw material is insufficient, but the shortage was supplemented with ordinary coke powder via the carbon material hopper 14 as in the past. For comparison, a conventional sintering operation without using the present invention was also performed.

Table 2 summarizes the operation results. According to Table 2, it can be seen that even if the ultrafine coke 2 is previously blended, the productivity and strength of the obtained sintered ore are comparable to those of the conventional product. In addition, as a result, the basic unit of coke in the production of sintered ore could be significantly reduced as compared with the conventional case. That is, it is understood that the compounding method according to the present invention is very effective for the sintering operation.

[0020]

[Table 1]

[0021]

[Table 2]

[0022]

As described above, according to the present invention,
A large amount of ultra-fine coke does not escape, and the fuel carbon material can be blended in advance with the sintering raw material. As a result, ultrafine coke, which has not been used conventionally, can be processed in the same steel mill, and a great economic effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a view for explaining a method of blending ultrafine coke into a sintering raw material according to the present invention, wherein (a) is a plan view showing a wet work, and (b) is a plan view showing whether the work is uniform in thickness. FIG. 1C and FIG. 1C show the stacking state of iron ore powder, and FIG.
FIG.

FIG. 2 is a diagram showing a facility arrangement of a sintering plant.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coal yard 2 Ultra fine coke 3 Sprayer 4 Water 5 Ore bedding yard (yard) 7 Rake 8 Iron ore powder 9 Mountain (bed) 10 Iron ore powder hopper 11 Limestone hopper 12 Dolomite hopper 13 Silica hopper 14 Carbon material hopper 15 Sieve Reference Signs List 16 mixer 17 sintering machine 18 mining hopper 19 ignition furnace 20 chute 21 water storage tank 22 tank / roller car 23 hose

Claims (4)

[Claims] 1. An iron ore powder for producing sinter ore, wherein various kinds of iron ore powder are piled up in layers on a rectangular yard having a bottom surface, cut out with a reclaimer in a direction perpendicular to the rectangular axis, and uniformly mixed. In preparing the first step, first, wet the ultrafine coke, then form a layer having a uniform thickness on the ground of the yard, and successively pile iron ore powder thereon so as to completely cover the ultrafine coke layer. A method of blending ultrafine coke into a sintering raw material, characterized by squeezing. 2. The ultra-fine coke according to claim 1, wherein a layer having a uniform thickness is formed by wet ultra-fine coke on a previously stacked iron ore powder layer instead of on the ground of the yard. For mixing sintering materials. 3. The method according to claim 1, wherein the wetting is performed by sprinkling and / or submerging. 4. The method of claim 3, wherein the water content of the ultrafine coke is constantly maintained in the range of 12 to 18% by weight in the water spraying and / or submerging treatment. Mixing method.