KR102217503B1 - Pressurized Steam Aging Device - Google Patents

Abstract

This pressurized steam aging device is a pressurized steam aging device for steelmaking slag that ages steelmaking slag with pressurized steam, and includes a slag storage container, a pressure container, a first pipe, and a second pipe, and the second pipe Silver is provided with a main pipe portion and a branch pipe portion having a jet hole formed on a side thereof, and when the dimension in the height direction of the storage area of the slag storage container is H (mm), 0.3 × H to 0.6 × in the storage area The ejection hole is disposed in the area in the height direction of H.

Description

Pressurized Steam Aging Device

The present invention relates to a pressurized steam aging apparatus for aging steelmaking slag containing unreconstituted lime (also referred to as free lime) discharged from a converter, electric furnace, etc. in a short time using pressurized steam.

This application claims priority based on patent application 2017-011870 for which it applied to Japan on January 26, 2017, and uses the content here.

The steelmaking slag generated in the steelmaking process is hard and has an angular shape on its surface, so it has good meshing during road voltage and has excellent properties as a roadbed material.

However, in steelmaking slag, part of the quicklime used as a dephosphorization agent and a desulfurization agent does not completely bind with other molecules and remains unreconstituted lime.

Therefore, when this steelmaking slag is used as it is as a roadbed material, it may cause a hydration reaction over time to expand and collapse, resulting in adverse effects such as ground uplift.

Therefore, when the steelmaking slag is used for a roadbed material or the like, aging is performed in advance to complete the swelling and collapse phenomenon, so that it can be used stably. In addition, aging is an operation of artificially swelling a steelmaking slag containing unreconstituted lime (free lime) in a short time using, for example, pressurized steam.

As a prior art document related to the aging method of steelmaking slag and its apparatus, patent document 1 is mentioned, for example.

In the technology proposed in Patent Document 1, after charging and sealing the crushed steelmaking slag at room temperature so that the grain size of 25 mm or less is 80% or more, pressurized steam is supplied into the pressure vessel to provide the pressure vessel and the slag. To heat. Then, while discharging the condensed hot water by the above operation, the inside of the pressure vessel is heated up and pressurized, and then the inside of the pressure vessel is maintained in a saturated steam atmosphere of 0.196 to 0.98 MPa for 1 to 5 hours, and then the inside of the pressure vessel is at atmospheric pressure. To discharge the steel slag.

In Patent Literature 2, the steelmaking slag characterized by discharging the air mixture vapor accumulated in the pressure vessel to the outside of the pressure vessel accompanying the heating/pressurizing process in the pressure vessel and the warming process in a saturated steam atmosphere. An aging method and apparatus have been proposed.

The outline of steam aging using the apparatus proposed in Patent Document 2 is shown in Figs. 9A and 9B. Steam aging using the apparatus proposed in Patent Document 2 is performed as follows. First, using a carrying device 101 such as a tractor excavator, the steel slag 102 to be steam-aged is charged into the unsealed slag storage container 103.

After that, the slag storage container 103 is transferred to the inside of the pressure container 104, and saturated water vapor of a predetermined pressure is supplied from the steam supply port 104a provided above it, and the inside of the pressure container 104 is The steelmaking slag 102 is aged by holding it at a predetermined time and a predetermined pressure. The steelmaking slag 102 after the aging treatment is carried out by opening the bottom of the slag storage container 103.

In addition, Patent Document 3 discloses a pressurized steam aging method and apparatus in which pressurized steam is widely spread in the slag in a short time and a hydration reaction is possible in a short time.

The steam aging device proposed in Patent Document 3 is the interior of the slag storage container 203 in which a pipe 205 for supplying pressurized steam is carried into the pressure container 204 as shown in FIGS. 10A and 10B. In this configuration, pressurized steam is supplied to the steelmaking slag charged into the slag storage container 203 through the hole 205a provided in the pipe 205.

However, even in the steam aging device of Patent Document 3, in particular, if the number of aging treatments of the steelmaking slag having a large proportion of powdery matter is repeated, the aging efficiency cannot be maintained due to clogging of the hole 205a. Equipment maintenance is required. Further, as shown in FIG. 10A, the pipe 205 is disposed in the longitudinal direction of the pressure vessel 204. In general, since the steel-making slag is introduced into the pressure vessel 204 from the vertical direction upward, the pipe 205 is damaged such as dents or curves by falling objects of the steel-making slag. Therefore, it is necessary to maintain equipment at high frequency.

In addition, Patent Document 4 discloses a method for aging steelmaking slag capable of completing an expansion reaction even if the steelmaking slag having a large proportion of particles is steam-aging.

However, even in the aging method of Patent Document 4, a decrease in aging efficiency due to clogging of holes or the like was inevitable.

Japanese Patent Laid-Open No. Hei 8-165151 Japanese Patent Publication No. Hei 9-118549 Japanese Patent Publication No. 2009-280445 Japanese Patent Publication No. 2012-41234

The present invention has been made in view of the above-described problems of the prior art, and its object is to increase aging efficiency while suppressing the frequency of equipment maintenance even when aging steel slag with a large proportion of powdery matter contained. It is to provide a pressurized steam aging device for steelmaking slag.

The summary of the present invention is as follows.

(1) One aspect of the present invention is a pressurized steam aging device for steelmaking slag for aging steelmaking slag with pressurized steam, a slag storage container in which the steelmaking slag is charged, a pressure container storing the slag storage container, A first pipe provided outside of the pressure vessel and supplying the pressurized steam to the inside of the pressure vessel, and a second pipe provided inside the pressure vessel and supplying the pressurized steam to the inside of the slag storage vessel The second pipe is provided with a pipe, a main pipe portion provided in a horizontal direction in the interior of the slag storage container, and a jet hole provided to erect upward from the main pipe portion and to eject the pressurized steam on a side surface With the formed branch pipe part, when the dimension in the height direction of the storage area of the slag storage container is H (mm), the ejection hole is in the height direction region of 0.3 x H to 0.6 x H in the storage area Is placed.

(2) In the pressurized steam aging device according to the above (1), the second pipe may further include a diameter enlarged portion having an outer diameter larger than the outer diameter of the branch pipe portion above the ejection hole of the branch pipe portion.

(3) In the pressurized steam aging device according to (2) above, the diameter enlarged portion may be provided at the tip end of the branch pipe portion.

(4) In the pressurized steam aging device described in (2) or (3) above, when the outer diameter of the enlarged diameter portion is D (mm) and the outer diameter of the branch pipe portion is d (mm), D≥2×d is satisfied. You can do it.

(5) In the pressurized steam aging device according to any one of (2) to (4) above, the center point of the ejection hole and the position closest to the center point of the ejection hole among the end edges of the lower surface of the diameter enlarged portion are connected. The angle of inclination from the horizontal line of the line may be 45° or less.

(6) In the pressurized steam aging device according to any one of (2) to (5) above, the separation distance between the lower end of the diameter expansion portion and the center point of the ejection hole is L1 (mm), and the outer diameter of the branch pipe portion is d ( Mm), L1≦d may be satisfied.

(7) In the pressurized steam aging device according to any one of (1) to (5) above, when the lengthwise dimension of the storage area of the slag storage container is L (mm), in the storage area The ejection hole may be disposed in a region of 0.2 x L to 0.8 x L in the longitudinal direction.

(8) In the pressurized steam aging device according to any one of (1) to (7) above, when the dimension in the width direction of the storage area of the slag storage container is W, 0.2×W in the storage area The ejection holes may be disposed in a region of to 0.8×W in the width direction.

(9) In the pressurized steam aging device according to any one of (1) to (8), a plurality of ejection holes may be provided in the circumferential direction of the branch pipe portion.

(10) In the pressurized steam aging device according to any one of (1) to (9), a plurality of the ejection holes may be provided in the height direction of the branch pipe portion.

According to the configuration described in the above (1), since the branch pipe portion is provided so as to stand upward, the steelmaking slag collides with the tip end of the branch pipe portion when the steelmaking slag is charged into the slag storage container. Therefore, since the filling degree of the steelmaking slag in the vicinity of the ejection hole of the pressurized steam formed on the side surface of the branch pipe portion is reduced, pressurized steam can be efficiently supplied to the central portion of the steelmaking slag. In addition, accompanying this, it is possible to prevent clogging of the ejection hole.

In addition, since the branch pipe portion is provided so as to stand upward from the main pipe portion, even if the ejection hole is disposed in the height direction region of 0.3 x H to 0.6 x H in the storage area, the main pipe portion is placed at a low position in the storage area. I can make it. Accordingly, when the steel slag is charged into the slag storage container, the number of times the steel slag collides with the main pipe part is suppressed to prevent physical damage to the main pipe part, and pressurized steam can be efficiently supplied to the center of the steel slag.

Therefore, even in the case where the proportion of powdery matter contained in the steelmaking slag is large, the aging efficiency can be improved while suppressing the frequency of equipment maintenance.

In addition, according to the configurations described in the above (2) to (10), the aging efficiency can be further increased while further suppressing the frequency of equipment maintenance.

1 is a schematic front view showing a schematic configuration of a steam aging device according to an embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view taken along line BB in FIG. 1 and shows a state in which the second pipe is removed.
3 is a schematic perspective view for explaining the dimensions of the storage area α.
4A is a schematic plan view showing a main pipe portion and a branch pipe portion.
4B is a schematic front view showing a main pipe portion and a branch pipe portion.
4C is a schematic diagram for explaining the dimensions of the branch pipe portion and the diameter enlarged portion.
Fig. 5A is a schematic view for explaining a jetting mode of pressurized steam when the filling degree of steelmaking slag is high in the vicinity of the jetting hole.
Fig. 5B is a schematic diagram for explaining a jetting mode of pressurized steam when the filling degree of steelmaking slag in the vicinity of the jetting hole is low.
6A is a schematic plan view showing a first modified example of a branch pipe portion.
6B is a schematic front view showing the modified example.
7A is a schematic plan view showing a second modified example of the branch pipe portion.
7B is a schematic front view showing the modified example.
8A is a schematic plan view showing a third modified example of the branch pipe portion.
8B is a schematic front view showing the modified example.
9A is a view for explaining an outline of steam aging using the equipment proposed in Patent Document 2.
9B is an enlarged view of the slag storage container of FIG. 9A.
10A is a side view illustrating a schematic configuration of a pressurized steam aging device proposed in Patent Document 3;
10B is a plan view illustrating a schematic configuration of a pressurized steam aging device proposed in Patent Document 3;

In the pressurized steam aging apparatus, the present inventors have conducted intensive examinations on increasing the aging efficiency while suppressing the frequency of equipment maintenance.

As a result, the following knowledge was obtained.

As in the prior art shown in FIGS. 10A and 10B, when a hole 205a for ejecting steam is formed in the pipe 205 arranged in the longitudinal direction, the steel slag in the vicinity of the hole 205a exists with a high degree of filling. do. In this case, ejection of steam from the hole 205a is prevented. In addition, there is a possibility that the hole 205a may be clogged with this. Accordingly, when a vapor hole is formed on the side of the branch pipe standing in the vertical direction, the steel slag dropped and charged from the upper side collides with the upper part of the pipe, thereby reducing the degree of filling of the steel slag in the vicinity of the hole. Thereby, it becomes possible to effectively eject the vapor from the hole and to prevent clogging.

Further, in the prior art shown in Figs. 10A and 10B, there is a concern that clogging may occur when the slag surface water (lime water) flows into the ejection hole. However, it becomes possible to alleviate the inflow of the slag surface water by forming the vapor hole in the side surface of the branch pipe part standing in the vertical direction.

In addition, in the prior art shown in FIGS. 10A and 10B, since the pipe 205 is disposed higher than the central portion in the height direction, the number of times the steel slag dropped and charged from the upper side collides with the pipe is large, and physical damage to the pipe There is a risk of this occurring. However, if the branch pipe part is provided so as to stand upright from the main pipe part provided in the horizontal direction, while the main pipe part is disposed at a lower position in the slag storage container, the height direction of 0.3 × H to 0.6 × H of the storage area of the slag storage container Eject holes can be placed in the area. Thereby, it is possible to efficiently advance steam aging while suppressing the frequency of equipment maintenance.

Hereinafter, with reference to the drawings, a pressurized steam aging device 1 (hereinafter simply referred to as ``steam aging device 1'') of a steel slag according to an embodiment of the present invention made based on the above-described knowledge. Explain.

As shown in Figs. 1 and 2, the steam aging device 1 according to the present embodiment is a device having a substantially cylindrical shape, and the slag storage container 11, the pressure container 12, and the first pipe 13 ) And a second pipe (14).

In the following description, the longitudinal direction X is a direction along the longitudinal direction of the steam aging device 1, the height direction Y is a vertical direction, and the width direction Z is a direction perpendicular to the longitudinal direction X and the height direction Y. to be.

The slag storage container 11 is a container that stores steelmaking slag in which steam aging is performed, and is constituted by a pair of storage members 111 and two support members 112 as shown in FIG. 2. .

Each receiving member 111 has an end surface 111e at both ends in the longitudinal direction of the bottom surface 111a, the first inclined surface 111b, the side surface 111c, and the second inclined surface 111d extending along the longitudinal direction X. It consists of concatenation.

The support member 112 has a column part 112a provided to stand upward from the bottom of the pressure vessel 12, and a shaft 112b extending along the longitudinal direction X from the upper end of the column part 112a. The shaft 112b is provided so as to be axially crosslinked with the column portion 112a in a state where the pair of end surfaces 111e are overlapped with each other, and each of the pair of storage members 111 is circumferentially attached to the shaft 112b Support for rotation.

An opening is formed above the slag storage container 11, and steelmaking slag is charged into the slag storage container 11 from this opening. In addition, in the example shown in FIG. 2, when the steelmaking slag is charged into the slag storage container 11, and when steam aging is performed, the tips of the pair of bottom surfaces 111a come into contact with each other and face each other. . However, some of the tip ends of the pair of bottom surfaces 111a may be overlapped with each other.

Then, after steam aging is performed, as shown by the two-dot chain line in Fig. 2, the pair of storage members 111 are opened around the shaft 112b, thereby discharging the steelmaking slag.

Further, for the operation of the storage member 111, a hydraulic cylinder or the like (not shown) may be used. In addition, when rotating the storage member 111 to discharge the steelmaking slag, in order to perform the work smoothly, the bottom of the storage member 111 is made into an arc shape, and a roller or the like (not shown) is installed below it. Also works.

In addition, when charging the slag steel making into the slag storage container 11, the slag storage container 11 is usually carried out to the outside of the pressure container 12 as shown in FIG. 9A. Therefore, the steam aging device 1 according to the present embodiment, when carrying out the slag storage container 11 from the pressure container 12, and when carrying in and installing the slag storage container 12 after charging the steelmaking slag, It is preferable that the main pipe portion 14a and the branch pipe portion 14b, which will be described later, are provided in an appropriate position inside the slag storage container 11 and can be carried in and out.

Here, with reference to FIG. 3, the storage area α of the slag storage container 11 will be described.

The storage area α is an inner space in the slag storage container 11 in which steelmaking slag is accommodated. 3 is an example showing the storage area α, and the shape of the slag storage container or the storage area α is not limited. The steelmaking slag may be charged to a position higher than the opening provided in the upper part of the slag storage container 11, but even in this case, the region higher than the opening is not included in the storage region α. That is, the storage area α does not depend on the amount of steel slag charged, but depends on the internal dimensions of the slag storage container 11.

As shown in Fig. 3, in the present application, for the storage area α, the length from the end to the end along each axis is referred to as a dimension, the dimension in the height direction Y is H (mm), and the dimension in the length direction X is The dimensions of L (mm) and the width direction Z are defined as W (mm).

The pressure container 12 is a container capable of sealing the slag storage container 11. The pressure vessel 12 is provided with an opening/closing lid 12a for allowing the slag storage vessel 11 to be carried in and discharged. The pressure vessel 12 is provided with a sensor (not shown) for measuring internal pressure and temperature. Further, in the pressure vessel 12, a first pipe 13 is disposed above the pressure vessel 12 (above the opening of the slag storage vessel 11) so that pressurized steam can be supplied therein, while The second pipe 14 is guided into the slag storage container 11 so that pressurized steam can be directly supplied to the steelmaking slag loaded in the slag storage container 11 carried into the slag storage container 11.

The first pipe 13 is provided outside the pressure vessel 12 and connected to the upper portion of the pressure vessel 12, and the pressurized steam supplied from the pressurized steam supply device 50 is supplied to the inside of the pressure vessel 12. To supply. The pressurized steam supplied through the first pipe 13 directly contacts the steelmaking slag exposed in the vicinity of the opening of the slag storage container 11, thereby promoting the progress of steam aging.

The second pipe 14 is provided inside the pressure vessel 12 and is connected to the side of the pressure vessel 12, and the pressurized steam supplied from the pressurized steam supply device 50 is transferred to the slag storage vessel 11. Supply inside.

The second pipe 14 includes a main pipe portion 14a and a branch pipe portion 14b, and ejects pressurized steam from a jet hole 14ba formed in the branch pipe portion 14b. Thereby, the progress of steam aging can be accelerated by bringing the pressurized steam into contact with the inside of the steelmaking slag charged in the slag storage container 11.

In addition, in the steam aging device 1 according to the present embodiment, the pressurized steam supply device 50 is connected to the first pipe 13 and the second pipe 14 through a pipe 52 having a valve 51. Are doing.

As shown in FIG. 1, the main pipe portion 14a is provided with connection pipe portions 14d connected to both ends in the longitudinal direction X, and along the longitudinal direction X in the slag storage container 11. The connection pipe portion 14d is provided in an inverted U shape so as to span the end surface 111e of the storage member 111 of the slag storage container 11. Then, the connection pipe portion 14d is connected to the pressurized steam supply device 50 provided outside the pressure container 12 through a valve 51 and a pipe 52.

It is preferable that the main pipe part 14a is provided in a height direction region of 0.1 × H to 0.3 × H in the storage area α of the slag storage container 11.

When the main pipe portion 14a is provided in the height direction region of less than 0.1 × H, the gap between the main pipe portion 14a and the slag storage container 11 becomes small, and the drain existing under the slag storage container 11 When the finely divided slag in the water has grown, there is a possibility that the gap will be filled. In this case, since it may cause a malfunction when opening the pair of accommodating members 111, it is preferable to provide the main pipe portion 14a in a height direction region of 0.1×H or more.

On the other hand, when the main pipe portion 14a is disposed in a height direction region of 0.3×H or less, even if the long branch pipe portion 14b is used, the ejection hole 14ba can be disposed in an appropriate height direction region. In this case, it is preferable in that it is possible to prevent clogging of the ejection holes 14ba caused by steelmaking slag present at a relatively high degree of filling by depositing on the upper part of the main pipe portion. In addition, when the main pipe portion 14a is disposed in the height direction region of 0.3×H or less, the number of collisions with the steel slag dropped from the opening is reduced, so that physical damage to the main pipe portion 14a can be prevented. Also preferred.

As shown in Figs. 4A and 4B, the branch pipe portion 14b is provided on the main pipe portion 14a by standing upward from a plurality of locations spaced at predetermined intervals along the longitudinal direction X. A plurality of branch pipe portions 14b may be provided, and at least one may be sufficient. A jet hole 14ba for pressurized steam is provided on the side surface of each branch pipe portion 14b. A plurality of ejection holes 14ba may be provided on the side surface of the branch pipe portion 14b, and a plurality of ejection holes 14ba may be provided in the circumferential direction of the branch pipe portion 14b. Further, on the side surface of each branch pipe portion 14b near the tip end, a plurality of ejection holes 14ba for pressurized steam are provided at isometric positions in the circumferential direction.

Pressurized steam supplied from the pressurized steam supply device 50 is ejected from the ejection hole 14ba through the main pipe portion 14a and the branch pipe portion 14b, and is supplied to the steel slag charged in the slag storage container 11 do.

Since the pressurized steam ejected from the ejection hole 14ba is ejected at a predetermined diffusion angle, as shown in Fig. 5A, when the filling degree of the steelmaking slag around the ejection hole 14ba is high, the pressurized steam is used as the steelmaking slag. On the other hand, as shown in Fig. 5B, when the filling degree of the steel-making slag around the ejection hole 14ba is low, the area where the pressurized steam collides with the steel-making slag increases.

In the steam aging device according to the present embodiment, since the branch pipe portion 14b is provided to stand upright, when the steel slag is dropped and charged into the slag storage container 11, steelmaking is made at the tip end of the branch pipe portion 14b. Slag collides Therefore, since the filling degree of the steelmaking slag in the vicinity of the ejection hole 14ba of the pressurized steam formed on the side surface of the branch pipe portion 14b decreases, it is possible to efficiently supply the pressurized steam to the center of the charged steelmaking slag. Further, it is possible to prevent clogging of the ejection hole accompanying this.

The ejection hole 14ba is disposed in a height direction region of 0.3 x H to 0.6 x H in the storage region α. Steam aging (hydration reaction) of the steelmaking slag is more than the opening of the slag storage container 11 or the vicinity of the pair of storage members 111 in which the pressurized steam supplied from the first pipe 13 directly contacts the slag storage container ( 11) in the center of the process is slow.

Therefore, by arranging the ejection holes 14ba in the height direction region of 0.3 × H to 0.6 × H in the storage area α, pressurized steam can be supplied to the steel slag from the center in the height direction of the charged steel slag, and steam aging Can proceed efficiently. Preferably, it is good also as 0.35xH-0.6xH, more preferably, 0.4xH-0.6xH, still more preferably, 0.45xH-0.6xH.

The position of the ejection hole 14ba in the height direction may be adjusted to the position where the ejection hole 14ba is formed in the branch pipe portion 14b, or may be adjusted to the height of the branch pipe portion 14b, or of the main pipe portion 14a. You may adjust it to the height direction position.

According to the steam aging device 1 according to the present embodiment, since the branch pipe portion 14b is provided to stand upward from the main pipe portion 14a, the height of 0.3 x H to 0.6 x H in the storage area α Even if the ejection hole 14ba is disposed in the direction region, the main pipe portion 14a can be disposed at a low position in the storage region α (for example, a height direction region of 0.1 × H to 0.3 × H). Therefore, when the steel slag is charged into the slag storage container 11, the number of times the steel slag collides with the main pipe portion 14a is suppressed to prevent physical damage to the main pipe portion 14a, while efficiently in the center of the charged steel slag. Pressurized steam can be supplied.

In order to advance steam aging more efficiently, it is preferable to supply pressurized steam to the longitudinal center of the steelmaking slag. Therefore, it is preferable that the ejection hole 14ba is provided in a lengthwise region of 0.2 x L to 0.8 x L in the storage area α of the slag storage container 11. More preferably, it may be 0.25 × L to 0.75 × L.

Likewise, in order to advance steam aging more efficiently, it is preferable to supply pressurized steam to the center portion in the width direction of the steelmaking slag. Therefore, it is preferable that the ejection hole 14ba is provided in the width direction region of 0.2×W to 0.8×W in the storage area α of the slag storage container 11. More preferably, it may be 0.3 × W to 0.7 × W, still more preferably 0.4 × W to 0.6 × W.

In the steam aging device 1 according to the present embodiment, as shown in FIG. 4C, a disk-shaped diameter enlarged portion having an outer diameter D larger than the outer diameter d of the branch pipe portion 14b at the tip end of the branch pipe portion 14b ( 14c) is formed. As shown in FIG. 4C, the outer diameter D of the diameter expansion part 14c is larger than the outer diameter d of the branch pipe part 14b. In addition, when the planar shape of the diameter enlarged part 14c is not circular, the equivalent circle diameter of the planar shape of the diameter enlarged part 14c is handled as an outer diameter.

When the diameter-enlarged portion 14c is formed, when the steel-making slag is charged into the slag storage container 11, the steel-making slag collides with the diameter-enlarged portion 14c of the tip of the branch pipe portion 14b. Therefore, the area in which the steelmaking slag collides is increased compared to the case where the diameter enlarged portion 14c is not formed. Therefore, since the filling degree of the steelmaking slag in the vicinity of the ejection hole 14ba of the pressurized steam formed on the side surface of the branch pipe portion 14b is further reduced, it is possible to efficiently supply the pressurized steam to the center of the charged steelmaking slag. . Further, it is possible to further prevent clogging of the ejection hole 14ba accompanying this.

In addition, in the case where the diameter enlarged portion 14c is formed, the effect of preventing the slag surface water (lime water) from flowing into the ejection hole 14ba can be further improved, so that clogging of the ejection hole 14ba is more prevented. You can definitely prevent it.

In addition, physical damage caused by the steel slag dropped and charged from the upper side collides with the main pipe portion 14a can be reduced.

The size (outer diameter or thickness, etc.) of the diameter enlarged portion 14c is the optimal size according to the outer diameter d of the branch pipe portion 14b and the position and size of the eruption hole 14ba in the rising direction so that the above-described effect occurs. Is determined. Conversely, the size of the ejection hole 14ba and the position to be provided may be appropriately determined according to the size of the diameter enlarged portion 14c.

In order to reduce the degree of filling of the steelmaking slag in the vicinity of the ejection hole 14ba, prevent clogging of the ejection hole 14ba, and further increase the efficiency of steam aging, one or more of the following conditions are satisfied. It is desirable.

(Condition 1) D≥2×d

(Condition 2) θ≤45°

(Condition 3) L1≤d

Here, as shown in Fig. 4c, D is the outer diameter (mm) of the diameter enlarged portion 14c, d is the outer diameter (mm) of the branch pipe portion 14b, and L1 is the diameter from the center point of the ejection hole 14ba. It is the separation distance (mm) to the lower end of the enlarged part 14c, θ is the center point of the ejection hole 14ba and the closest to the center point of the ejection hole 14ba among the end edges of the lower surface of the diameter enlarged portion 14c. It is the inclination angle (°) from the horizontal line of the line connecting the position

The outer diameter and thickness of the main pipe portion 14a and the branch pipe portion 14b, the upward standing direction and length of the branch pipe portion 14b, the number of installations (installation interval), and a spout hole provided on the side of the branch pipe portion 14b ( The number and size of 14ba) are not particularly limited as long as the effect of the present invention is obtained. That is, the outer diameter and thickness of the main pipe portion 14a and the branch pipe portion 14b are dimensions that can withstand the amount of pressurized steam to be supplied to the steelmaking slag, the impact during charging of the charged steel slag, or the weight of the steelmaking slag after charging. Decide. In addition, the vertical direction and length of the branch pipe portion 14b are, depending on the installation position of the slag storage container 11 of the main pipe portion 14a, the ejection hole 14ba provided in the branch pipe portion 14b is a slag It may be determined to be disposed at an appropriate position in the storage area?

According to the steam aging device 1 according to the above embodiment, even when the steelmaking slag having a large proportion of powdery matter is charged into the slag storage container 11, the filling degree of the steelmaking slag in the vicinity of the ejection hole 14ba is controlled. While making it small, it is possible to prevent clogging of the ejection hole 14ba. Accordingly, it is possible to effectively supply pressurized steam to the center of the steel slag charged in the slag storage container 11, and together with the pressurized steam supplied into the pressure vessel 12 from the first pipe 13, steelmaking slag in a short time. The steam aging of can proceed. Thereby, it becomes possible to efficiently advance aging while suppressing the frequency of equipment maintenance.

It goes without saying that the present invention is not limited to the above examples, and embodiments may be appropriately changed as long as it is the scope of the technical idea described in each claim.

For example, the number of installations (installation intervals) of the branch pipe portion 14b, the circumferential direction and the position, number, and size of the ejection holes 14ba provided in the branch pipe portion 14b are examples shown in the above embodiment. It is not limited to, and may be determined so that pressurized steam can be effectively supplied to the steelmaking slag located in the center of the slag storage container 11.

The branch pipe portion 14b may be inclined in the longitudinal direction X as in the first modification shown in Figs. 6A and 6B to stand up, or in the width direction Z as in the second modification shown in Figs. 7A and 7B. It may be tilted to stand, or may be tilted in the longitudinal direction X and the width direction Z as in the third modified example shown in Figs. 8A and 8B to stand.

In addition, a plurality of ejection holes 14ba may be provided in the height direction Y of the branch pipe portion 14b as in the first to third modifications shown in FIGS. 6A to 8B. When the ejection holes 14ba are provided in a plurality of locations, it is preferable that all of the ejection holes 14ba are arranged in a height direction region of 0.3xH to 0.6xH in the storage area α.

In the steam aging device 1 according to the above embodiment, the second pipe 14 has the diameter enlarged portion 14c, but it is not necessary to have the diameter enlarged portion 14c.

In the steam aging device 1 according to the above embodiment, the main pipe portion 14a is provided along the length direction X of the slag storage container 11, but may be provided to meander in the width direction Z. That is, the main pipe part 14a just needs to be provided along the horizontal direction.

In the vapor aging device 1 according to the above embodiment, the ejection holes 14ba of all the branch pipe portions 14b are all the same size, but they may be different.

In the steam aging device 1 according to the above embodiment, the ejection hole 14ba provided in the branch pipe portion 14b is circular, but the shape of the ejection hole 14ba is not limited to a circular shape, and may be an oval or polygonal shape. Further, the branch pipe portion 14b may be provided with a slit.

In the steam aging device 1 according to the above embodiment, a disk-shaped diameter enlarged portion 14c is provided at the tip end of the branch pipe portion 14b. However, the shape of the diameter enlarged portion 14c as viewed from the plane may be an ellipse or a polygon. Moreover, even if it is not a plate shape, a conical shape may be sufficient. In addition, the position where the diameter expansion part 14c is provided does not have to be the tip end of the branch pipe part 14b, and just needs to be above the ejection hole 14ba.

The vapor aging device 1 according to the above embodiment has only one main pipe portion 14a. However, the capacity of the slag storage container 11 increases, and only the pressurized steam ejected from the branch pipe portion 14b provided in the one main pipe portion 14a allows the pressurized steam to be supplied to the center of the steelmaking slag charged in the slag storage container 11. In the case where it cannot be effectively supplied, a plurality of main pipe portions 14a including the branch pipe portions 14b may be used.

(Example)

In Experimental Example 1, the steam aging apparatus 1 shown in Fig. 1 was used, and in Experimental Examples 2 to 9, a steam aging apparatus in which various modifications were applied to the steam aging apparatus 1 were used to perform steam aging treatment. I did.

The main common conditions in each experimental example are as follows.

·Average particle diameter of steelmaking slag: As the particle diameter of steelmaking slag, the standard of steel slag for road use is 0-40㎜

·Pressure in pressure vessel: 0.5 MPa

·Height of storage area: 1790㎜

·Storage area width W: 2800㎜

·Length of storage area L: 6400㎜

·Location of main pipe in width direction: 0.5×W

·Diameter of main pipe: 4.5㎜

Steam aging time: 2 hours/cycle

Steelmaking slag amount: 45t/cycle

In Experimental Examples 1 to 8, branch pipe portions were erected on the main pipe portion at four longitudinal positions of 0.25×L, 0.42×L, 0.58×L, and 0.75×L. In addition, eight ejection holes were provided in each branch pipe at equal intervals in the circumferential direction. Thereby, it was set as the structure in which steam is blown out from 32 jetting holes.

On the other hand, in Experimental Example 9, as shown in Figs. 10A and 10B, a branch pipe part was not provided, and a main pipe part was provided at a height of 710 mm and 1530 mm of the storage area, and 10 ejection holes were formed for each side of each main pipe part. It was arranged at equal intervals in a row in directions. Thereby, it was set as the structure in which the steam was blown out from a total of 40 jet holes in two main pipe parts.

In the experiment, in order to perform aging once, a step of charging steel slag to the steam aging device 1 and then heating it to a predetermined temperature, and a step of setting the temperature to a predetermined temperature after the end of the steam aging is required. A total of 1 hour is required for these processes. That is, in the experiment, the time required until the steelmaking slag is charged into the steam aging device 1 to perform steam aging treatment, and the steelmaking slag is discharged from the steam aging device 1 is 3 hours/cycle. .

In one day, the above experiment was conducted 8 cycles to treat 360 tons/day of steelmaking slag. The above experiment was carried out for 8 cycles, and the steelmaking slag treatment of 360 tons/day was performed for 1 month, 3 months and 6 months without stopping the operation.

Table 1 shows the individual conditions in each experimental example.

The steelmaking slag after the above steam aging treatment was subjected to a water immersion expansion test specified in Annex B of JIS A 5015 (2013), and the water immersion expansion ratio was measured. The results are shown in Table 2.

a: Water immersion expansion test result of steelmaking slag before steam aging: Water immersion expansion ratio (%)

b: Water immersion expansion test result of steelmaking slag after steam aging: Water immersion expansion ratio (%)

Reduction rate: Reduction rate=(b/a)×100(%)

Initial implementation: Results of immersion expansion test on the aged slag on the first day

1 month after implementation: Results of the immersion expansion test of steam-aged slag in the operation after daily operation for 1 month

3 months after implementation: Results of immersion expansion test of steam-aged slag in operation after daily operation for 3 months

6 months after implementation: Results of immersion expansion test of steam aged slag in operation after daily operation for 6 months

In Experimental Examples 1 to 4, since steam aging was performed under appropriate conditions, steam aging could be performed with high efficiency. In particular, in Experimental Examples 1, 2, and 4 in which the diameter enlarged portion was provided, particularly good results were obtained as compared to Experimental Example 3 in which the diameter enlarged portion was not provided. This is because the degree of filling of the steelmaking slag in the vicinity of the ejection hole can be further reduced by the diameter enlarged portion, and pressurized steam can be supplied from the inside of the steelmaking slag to the whole while suppressing the occurrence of nozzle clogging. Is inferred.

In Experimental Examples 5 to 8, steam aging with high efficiency was not possible. Since the ejection holes were not arranged in the height direction region of 0.3 x H to 0.6 x H, it is speculated that pressurized steam could not be sufficiently supplied to the center of the slag.

In Experimental Example 9, steam aging with high efficiency was not possible. Since the ejection holes are formed in the main piping and are arranged in a height direction region higher than 0.6×H, it is speculated that the slag ejection holes are clogged and physical damage to the main piping has occurred.

In addition, at the time of regular inspection, it was confirmed that nozzle clogging occurred in the ejection hole. In particular, it is presumed that the clogging of the nozzle of this ejection hole deteriorated the efficiency of steam aging.

The present invention described above is not limited to targeting steelmaking slag with a large blending ratio of powdery matter, but can also be applied to steelmaking slag having a grain size of a conventional roadbed material.

1: steam aging device
11: slag storage container
111: a pair of storage members
111a: bottom
111b: first slope
111c: side
111d: second slope
111e: end face
112: support member
112a: pillar
112b: shaft
α: storage area
12: pressure vessel
12a: opening and closing cover
13: first pipe
14: second pipe
14a: main administration
14b: Branch Office
14ba: ejection hole
14c: diameter enlarged part
14d: connection pipe part
50: pressurized steam supply device
51: valve
52: piping

Claims (10)

It is a pressurized steam aging device for steel making slag that ages steel slag with pressurized steam,
A slag storage container into which the steelmaking slag is charged,
A pressure container accommodating the slag storage container,
A first pipe provided outside the pressure vessel and supplying the pressurized steam supplied from a pressurized steam supply device to the inside of the pressurized vessel;
A second pipe provided inside the pressure vessel and supplying the pressurized steam supplied from the pressurized steam supply device to the inside of the slag storage vessel
Equipped,
The second pipe includes a main pipe portion provided in a horizontal direction in the interior of the slag storage container, and a branch pipe portion provided to stand upward from the main pipe portion and a branch pipe portion having a jet hole for ejecting the pressurized steam on a side surface. and,
When the dimension in the height direction of the storage area of the slag storage container is H (mm), the ejection hole is disposed in a height direction region of 0.3 x H to 0.6 x H in the storage area,
The second piping further includes a diameter enlarged portion having an outer diameter larger than an outer diameter of the branch pipe portion above the ejection hole of the branch pipe portion. delete The method of claim 1,
A pressurized steam aging device, characterized in that the diameter enlarged portion is provided at the tip of the branch pipe portion. The method of claim 1 or 3,
When the outer diameter of the diameter enlarged portion is D (mm) and the outer diameter of the branch pipe portion is d (mm), D≥2×d is satisfied. The method of claim 1 or 3,
The pressurized steam aging apparatus, characterized in that the inclination angle from the horizontal line of the line connecting the center point of the ejection hole and the position closest to the center point of the ejection hole among the end edges of the lower surface of the diameter expansion portion is 45° or less. The method of claim 1 or 3,
When the separation distance between the lower end of the diameter expansion part and the center point of the ejection hole is L1 (mm), and the outer diameter of the branch pipe is d (mm), L1≦d is satisfied. The method of claim 1 or 3,
When the lengthwise dimension of the storage area of the slag storage container is L (mm), the ejection hole is disposed in a longitudinal region of 0.2×L to 0.8×L in the storage area, Pressurized steam aging device. The method of claim 1 or 3,
When the dimension in the width direction of the storage area of the slag storage container is W, the ejection hole is disposed in a width direction area of 0.2×W to 0.8×W in the storage area, pressurized steam aging Device. The method of claim 1 or 3,
A pressurized steam aging device, characterized in that a plurality of ejection holes are provided in a circumferential direction of the branch pipe portion. The method of claim 1 or 3,
A pressurized steam aging device, characterized in that a plurality of the ejection holes are provided in a height direction of the branch pipe portion.

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