TWI649296B - Pressure type steam aging apparatus - Google Patents

Abstract

The pressurized steam curing device is a pressurized steam curing device for slag aging of steelmaking slag by pressurized steam, and includes a slag storage container, a pressure vessel, a first pipe, and a second pipe, The second pipe is provided with a main pipe and a branch pipe portion having a discharge hole formed on the side surface thereof. When the dimension of the storage region of the slag storage container is H (mm), the discharge hole is 0.3×H disposed in the storage region. ~0.6×H height direction area.

Description

Pressurized steam curing device

The present invention relates to a pressurized steam curing apparatus capable of aging a steel slag containing unslagized lime (also referred to as free lime) discharged from a converter, an electric furnace or the like by using pressurized steam in a short time. . The case is based on the priority of 2017-011870, which was filed in Japan on January 26, 2017, and the content of the case is hereby applied.

The steel slag generated in the steel making process is hard and the surface thereof is formed into an angular shape, so that the nip property at the time of road rolling is good, and it has excellent properties as a road base material.

However, in the steel slag, a part of the quicklime used as the dephosphorization agent and the desulfurizing agent does not completely bond with other molecules, and remains in the state of the unslagized lime.

Therefore, when the steel slag is directly used as a road base material, it may expand and disintegrate due to a hydration reaction over time, causing disadvantages such as foundation bulging.

Therefore, when the steel slag is used as a road base material or the like, the aging is performed in advance to complete the expansion and disintegration, so that it can be used stably. Further, aging refers to an operation of swelling a steel slag containing unslagized lime (free lime) in a short time by, for example, pressurized steam.

The prior art document of the method for aging the steel slag and the apparatus thereof can be exemplified by Patent Document 1.

The technique proposed in Patent Document 1 is to make the crushed steel slag at room temperature into a particle size of 25 mm or less, which accounts for 80% or more, and is placed in a pressure vessel and sealed, and then pressurized steam is supplied into the pressure vessel to heat the pressure vessel. And slag. Further, the hot water condensed by the above operation is discharged, and the temperature rise and pressure increase in the pressure vessel are simultaneously performed, and then the pressure vessel is held in a saturated water vapor atmosphere having a pressure of 0.196 to 0.98 MPa for 1 to 5 hours, and then the pressure vessel is placed. The internal pressure is reduced to atmospheric pressure, and the steel slag is discharged.

Patent Document 2 proposes a method and an apparatus for aging a steelmaking slag, which are characterized in that a mixture of the inside of the pressure vessel is mixed with a temperature rising and a pressure increasing step in the pressure vessel and a heat insulating step in a saturated water vapor environment. The vapor of the air is discharged toward the outside of the pressure vessel.

9A and 9B show an outline of steam curing using the apparatus proposed in Patent Document 2. The steam curing using the apparatus proposed in Patent Document 2 is carried out as follows. First, the steel slag 102 for steam curing is placed in a non-sealed slag storage container 103 by using a hoisting machine such as a shovel and the loading device 101.

After that, the slag storage container 103 is transferred to the inside of the pressure vessel 104, and saturated steam of a predetermined pressure is supplied from the steam supply port 104a provided above the pressure vessel 104, and the inside of the pressure vessel 104 is kept for a predetermined period of time. Under the pressure, the aging of the steel slag 102 is performed. The steel slag 102 in which the aging treatment is completed is carried out by opening the bottom of the slag storage container 103.

Further, Patent Document 3 discloses a pressurized steam curing method and apparatus which can carry out a hydration reaction in a short time by passing pressurized steam throughout the slag.

As shown in FIG. 10A and FIG. 10B, the steam aging apparatus proposed in the patent document 3 is configured to guide the piping 205 that supplies the pressurized steam to the inside of the slag storage container 203 that has been carried into the pressure vessel 204, and is provided from the inside. The hole 205a of the pipe 205 supplies pressurized steam to the steel slag that has been placed in the slag storage container 203.

However, even in the steam curing apparatus of the patent document 3, the number of times of the aging process of the steel slag in which the proportion of the powder is particularly large is repeated, and the aging of the hole 205a or the like is prevented, and the aging efficiency cannot be maintained. Higher frequency equipment maintenance. Moreover, as shown in FIG. 10A, the piping 205 is disposed in the longitudinal direction of the pressure vessel 204. Usually, since the input of the steel slag to the pressure vessel 204 is performed from the vertical direction, the pipe 205 is damaged by the depression or the bending due to the falling of the steel slag. Therefore, higher frequency equipment maintenance is required.

Further, Patent Document 4 discloses a method for aging a steel slag which can complete an expansion reaction even when steam aging of a steel slag having a large ratio of particles is performed.

However, even in the aging method of Patent Document 4, it is impossible to avoid a decrease in the aging efficiency due to clogging of the holes or the like.

CITATION LIST Patent Literature Patent Literature 1: Japanese Laid-Open Patent Publication No. Hei No. Hei. No. Hei. No. Hei. No. Hei. No. 9-118549. Opening No. 2012-41234

Disclosure of the Invention Problems to be Solved by the Invention The present invention has been made in view of the above problems of the prior art, and an object of the invention is to provide a pressurized steam curing device for steelmaking slag, which has a high content ratio of powders. When the steel slag is matured, the frequency of equipment maintenance can also be suppressed, and the curing efficiency can be improved.

Means for Solving the Problems The outline of the present invention is as follows.

(1) An aspect of the present invention is a pressurized steam curing apparatus for a steelmaking slag which is aged by a pressurized steam, comprising: a slag storage container for charging the steelmaking slag; and a pressure vessel The first sump is disposed outside the pressure vessel for supplying the pressurized vapor to the inside of the pressure vessel; and the second pipe is provided inside the pressure vessel for the The pressurized steam is supplied to the inside of the slag storage container, and the second pipe includes a main pipe portion that is provided inside the slag storage container in a horizontal direction, and a branch pipe portion that is provided upward from the main pipe portion and is laterally provided a discharge hole through which the pressurized steam is discharged is formed. When the dimension of the storage region of the slag storage container is H (mm), the discharge hole is disposed at a height of 0.3×H to 0.6×H of the storage region. Direction area.

(2) The pressurized steam maturation apparatus according to the above aspect (1), wherein the second pipe may further include an enlarged diameter portion above the discharge hole of the branch pipe portion, and the enlarged diameter portion has a larger diameter than the branch pipe The outer diameter of the outer diameter is larger. (3) The pressurized steam curing device according to (2), wherein the enlarged diameter portion may be provided at a front end of the branch pipe portion. (4) In the pressurized steam curing apparatus according to (2) or (3), the outer diameter of the enlarged diameter portion may be D (mm), and the outer diameter of the branch portion may be d (mm). When D,2×d is satisfied. (5) The pressurized steam maturation apparatus according to any one of the above-mentioned (2), wherein the center point of the discharge hole and the edge of the lower surface of the enlarged diameter portion are separated from the discharge hole. The line at the nearest position of the center point has an inclination angle of 45° or less from the horizontal line. (6) The pressurized steam maturation apparatus according to any one of the above (2), wherein the separation distance between the lower end portion of the enlarged diameter portion and the center point of the discharge hole is L1. (mm), when the outer diameter of the branch pipe portion is d (mm), L1 ≦ d is satisfied.

(7) In the pressurized steam curing apparatus according to any one of the above aspects, the size of the storage area of the slag storage container may be L (mm). The discharge hole is a long-side direction region of 0.2 × L to 0.8 × L disposed in the storage region. (8) In the pressurized steam curing apparatus according to any one of the above aspects, the storage hole of the storage area of the slag storage container may be W, and the discharge holes may be arranged. In the width direction region of 0.2 × W to 0.8 × W in the storage region. In the pressurized steam curing apparatus according to any one of the above aspects, the plurality of the discharge holes may be provided in the circumferential direction of the branch pipe portion. (10) In the pressurized steam curing apparatus according to any one of the above aspects, the plurality of discharge holes may be provided in a plurality of places 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 to rise upward, the steel slag collides with the front end of the branch pipe portion when the steel slag is placed in the slag storage container. Therefore, the degree of filling of the steel slag near the discharge hole of the pressurized steam formed on the side surface of the branch pipe portion is lowered, so that the pressurized steam can be efficiently supplied to the center portion of the steel slag. Further, along with this, clogging of the discharge holes can be prevented. Further, since the branch pipe portion is provided upward from the main pipe portion, the main pipe portion can be disposed at a low position of the storage region even if the discharge hole is disposed in a height direction region of 0.3 × H to 0.6 × H in the storage region. Therefore, when the steel slag is placed in the slag storage container, the number of times the steel slag hits the main pipe portion can be suppressed, the physical damage of the main pipe portion can be prevented, and the pressurized steam can be efficiently supplied to the center portion of the steel slag. Therefore, even if the content of the powder in the steel slag is large, the frequency of maintenance of the equipment can be suppressed, and the aging efficiency can be improved. Moreover, according to the configuration described in the above (2) to (10), the frequency of maintenance of the equipment can be further suppressed, and the aging efficiency can be further improved.

MODE FOR CARRYING OUT THE INVENTION The inventors of the present invention have conducted intensive studies on suppressing the frequency of equipment maintenance and improving the aging efficiency in the pressurized steam curing apparatus.

As a result, the following findings were obtained. In the conventional technique shown in FIG. 10A and FIG. 10B, when the piping 205 disposed in the longitudinal direction is formed with the hole 205a for discharging the vapor, the steel slag near the hole 205a exists in a state of high filling. In this case, the ejection of the vapor from the hole 205a is hindered. Further, with this, there is a fear that clogging of the hole 205a occurs. Therefore, when the vapor hole is formed on the side surface of the branch pipe portion which rises in the vertical direction, the steel slag which is dropped from above and is loaded hits the upper portion of the pipe, and the degree of filling of the steel slag near the hole can be lowered. Thereby, the discharge of the vapor from the hole can be efficiently performed, and clogging can be prevented. Further, in the conventional technique shown in Figs. 10A and 10B, there is a fear that clogging occurs due to the slag surface water (lime water) flowing into the discharge hole. However, by allowing the vapor hole to be formed on the side surface of the branch pipe portion that rises in the vertical direction, the inflow of water on the surface of the slag can be alleviated. Furthermore, in the conventional technique shown in FIG. 10A and FIG. 10B, since the piping 205 is disposed higher than the center portion in the height direction, the number of times that the steel slag which is dropped from above is hitting the piping is large, and the piping may be physically generated. Damage. However, when the branch pipe portion is provided to stand up in the vertical direction from the main pipe provided in the horizontal direction, the main pipe portion can be disposed at a low position in the slag storage container, and the discharge hole can be disposed in the storage region of the slag storage container. The height direction area of 0.3×H~0.6×H. Thereby, the frequency of maintenance of the apparatus can be suppressed, and steam curing can be performed efficiently.

In the following, the pressurized steam curing apparatus 1 (hereinafter simply referred to as "steam curing apparatus 1") of the steel slag according to the embodiment of the present invention, which is based on the above-described findings, will be described with reference to the drawings.

As shown in FIG. 1 and FIG. 2, the steam maturation apparatus 1 of the present embodiment is a substantially cylindrical device, and includes a slag storage container 11, a pressure vessel 12, a first pipe 13, and a second pipe 14. In the following description, the longitudinal direction X means a direction along the longitudinal direction of the steam curing device 1, the height direction Y means a vertical direction, and the width direction Z means a direction perpendicular to the longitudinal direction X and the height direction Y.

The slag storage container 11 is a container that accommodates steel slag for steam maturation, and is composed of a pair of storage members 111 and two support members 112 as shown in FIG. 2 .

Each of the storage members 111 is configured by connecting end faces 111e at both end portions 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 in the longitudinal direction X.

The support member 112 has a column portion 112a that rises upward from the bottom of the pressure vessel 12, and a shaft 112b that extends from the upper end of the column portion 112a in the longitudinal direction X. The shaft 112b is provided on the column portion 112a in a state in which the pair of end faces 111e overlap each other, and each of the pair of housing members 111 is rotatably supported by the shaft circumference of the shaft 112b.

An opening is formed in the upper portion of the slag storage container 11, and the steel slag is placed inside the slag storage container 11 from the opening. In the example shown in FIG. 2, when the steel slag is placed in the slag storage container 11, and when the steam is aged, the front ends of the pair of bottom surfaces 111a are in contact with each other and face each other. However, the front ends of the pair of bottom faces 111a may be in a state in which a part thereof overlaps each other. After the steam curing is performed, as shown by the two-dot chain line of FIG. 2, the pair of storage members 111 are opened around the shaft 112b, thereby discharging the steel slag. Further, a hydraulic cylinder or the like (not shown) may be used for the operation of the storage member 111. Moreover, when the storage member 111 is rotated in order to discharge the steel slag, the bottom of the storage member 111 may be formed in an arc shape in order to smoothly perform the work, and a roller or the like (not shown) may be provided below the storage member 111.

When the steel slag is charged into the slag storage container 11, the slag storage container 11 is usually carried out to the outside of the pressure vessel 12 as shown in FIG. 9A. Therefore, the steam curing apparatus 1 of the present embodiment is preferably configured such that when the slag storage container 11 is carried out of the pressure vessel 12 and loaded into the steel slag and then placed in the pressure vessel 12, the main pipe portion 14a and the branch pipe portion 14b are described later. It is placed in an appropriate position inside the slag storage container 11, and can be carried in and out.

Here, the storage area α of the slag storage container 11 will be described with reference to Fig. 3 . The storage area α is an internal space in which the steel slag is stored in the slag storage container 11. FIG. 3 shows an example of the storage area α, and the shape of the slag storage container or the storage area α is not limited to this example. The steel slag may be placed at a higher position than the opening provided in the upper portion of the slag storage container 11, but in this case, a region higher than the opening portion is not included in the storage region α. That is, the storage area α is not determined depending on the amount of the steel slag to be charged, and is determined depending on the internal size of the slag storage container 11. As shown in FIG. 3, in the present case, in the storage area α, the length from the end to the end along each axis is taken as the size, and the dimension in the height direction Y is defined as H (mm), The dimension of the longitudinal direction X is defined as L (mm), and the dimension of the width direction Z is defined as W (mm).

The pressure vessel 12 is a closable container that houses the slag storage container 11. The pressure vessel 12 is provided with an opening and closing cover 12a that can be used for loading and discharging the slag storage container 11. The pressure vessel 12 is provided with a sensor (not shown) for measuring the internal pressure and temperature. Further, in the pressure vessel 12, the first pipe 13 is disposed in the upper portion of the pressure vessel 12 (above the opening of the slag storage container 11) to supply pressurized steam to the inside, and the second pipe 14 is guided to the slag storage. The inside of the container 11 is supplied with the pressurized steam directly into the steel slag loaded in the slag storage container 11 that has been carried into the inside.

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

The second pipe 14 is provided inside the pressure vessel 12 and is connected to the side of the pressure vessel 12, and supplies the pressurized steam supplied from the pressurized steam supply device 50 to the inside of the slag storage container 11. The second pipe 14 includes a main pipe portion 14a and a branch pipe portion 14b, and discharges pressurized steam from the discharge holes 14ba formed in the branch pipe portion 14b. Thereby, the pressurized steam can be brought into contact with the inside of the steel slag charged in the slag storage container 11, thereby promoting the progress of steam ripening.

Further, in the steam curing device 1 of the present embodiment, the pressurized steam supply device 50 is connected to the first pipe 13 and the second pipe 14 through the pipe 52 having the valve 51.

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

The main pipe portion 14a is preferably a height direction region of 0.1 × H to 0.3 × H provided in the storage region α of the slag storage container 11. When the main pipe portion 14a is disposed 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 when the fine powder slag present in the discharge water below the slag storage container 11 increases, I am afraid the gap will be filled. In this case, it may be a cause of an erroneous operation when the pair of storage members 111 are opened. Therefore, the main tube portion 14a is preferably provided in a height direction region of 0.1 × H or more. On the other hand, when the main pipe portion 14a is disposed in the height direction region of 0.3 × H or less, the discharge hole 14ba can be disposed in an appropriate height direction region even if the long branch pipe portion 14b is used. In this case, it is preferable to prevent clogging of the discharge holes 14ba due to the steel slag which is deposited on the upper portion of the main pipe portion and has a relatively high filling degree. Further, 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 portion is reduced, so that the physical damage of the main pipe portion 14a can be prevented. .

As shown in FIG. 4A and FIG. 4B, the branch pipe portion 14b is provided at a plurality of predetermined intervals along the longitudinal direction X in the main pipe portion 14a, and is provided to stand upward. The branch pipe portion 14b may be provided in plural, and at least one may be provided. The side surface of each branch pipe portion 14b is provided with a discharge port 14ba for pressurizing steam. The ejection holes 14ba may be provided in a plurality of sides on the branch pipe portion 14b, or a plurality of the circumferential portions in the circumferential direction of the branch pipe portion 14b. Further, on the side surface near the front end of each branch pipe portion 14b, a plurality of pressure vapor discharge holes 14ba are provided at equiangular positions in the circumferential direction. The pressurized steam supplied from the pressurized steam supply device 50 is discharged from the discharge holes 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.

Since the pressurized vapor ejected from the ejection holes 14ba is ejected at a predetermined diffusion angle, as shown in FIG. 5A, when the filling degree of the steel slag around the ejection hole 14ba is high, the area of the pressurized vapor impinging on the steel slag becomes small. On the other hand, as shown in FIG. 5B, when the filling degree of the steel slag around the discharge hole 14ba is low, the area where the pressurized steam impinges on the steel slag becomes large. In the steam curing apparatus of the present embodiment, the branch pipe portion 14b is erected upward. When the steel slag is dropped into the slag storage container 11, the steel slag hits the front end of the branch pipe portion 14b. Therefore, the degree of filling of the steel slag near the discharge hole 14ba of the pressurized steam formed on the side surface of the branch pipe portion 14b is lowered, so that the pressurized steam can be efficiently supplied to the center portion of the loaded steel slag. Further, along with this, clogging of the discharge holes can be prevented.

The discharge hole 14ba is a height direction region disposed in the storage area α of 0.3×H to 0.6×H. The steam aging (hydration reaction) of the steel slag is in the center of the slag storage container 11 in comparison with the opening of the slag storage container 11 or the vicinity of the pair of storage members 111 which are directly contacted by the pressurized steam supplied from the first pipe 13 The Department’s progress is slower. Therefore, by arranging the discharge holes 14ba in the height direction region of 0.3 × H to 0.6 × H in the storage region α, the pressurized slag can be supplied from the center portion in the height direction of the loaded steel slag, and the pressure can be efficiently performed. Steam curing. It should be 0.35×H~0.6×H, preferably 0.4×H~0.6×H, more preferably 0.45×H~0.6×H. The position in the height direction of the discharge hole 14ba can be adjusted by the position at which the discharge hole 14ba of the branch portion 14b is formed, or the height of the branch portion 14b can be adjusted, or the position of the main portion 14a can be adjusted in the height direction.

According to the steam curing apparatus 1 of the present embodiment, since the branch pipe portion 14b is provided upward from the main pipe portion 14a, even if the discharge hole 14ba is disposed in the height direction region of the storage region α of 0.3 × H to 0.6 × H, The main pipe portion 14a can be disposed at a low position of the storage area α (for example, a height direction region of 0.1 × H to 0.3 × H). Therefore, when the steel slag is placed in the slag storage container 11, the number of times the steel slag is hit against the main pipe portion 14a can be suppressed, the physical damage of the main pipe portion 14a can be prevented, and the pressurized steam can be efficiently supplied to the loaded steel. The center of the slag.

In order to perform steam ripening more efficiently, the pressurized steam is preferably supplied to the center portion in the longitudinal direction of the steel slag. Therefore, in the storage area α of the slag storage container 11, the discharge hole 14ba is preferably provided in a longitudinal direction region of 0.2 × L to 0.8 × L. It is preferably set in a long-side direction region of 0.25 × L - 0.75 × L.

Similarly, in order to perform steam ripening more efficiently, the pressurized steam is preferably supplied to the center portion in the width direction of the steel slag. Therefore, in the storage area α of the slag storage container 11, the discharge hole 14ba is preferably provided in a width direction region of 0.2 × W to 0.8 × W. It is more preferably a width direction region of 0.3 × W to 0.7 × W, and more preferably a width direction region of 0.4 × W to 0.6 × W.

In the steam curing device 1 of the present embodiment, as shown in Fig. 4C, a disk-shaped enlarged diameter portion 14c is formed at the tip end of the branch pipe portion 14b, and the enlarged diameter portion 14c has a larger outer diameter d than the branch pipe portion 14b. Outer diameter D. As shown in FIG. 4C, the outer diameter D of the enlarged diameter portion 14c is larger than the outer diameter d of the branch pipe portion 14b. In addition, when the shape of the enlarged diameter portion 14c is not circular, the equivalent circular diameter of the enlarged shape of the enlarged diameter portion 14c is treated as an outer diameter.

When the enlarged diameter portion 14c is formed, when the steel slag is placed in the slag storage container 11, the steel slag collides with the enlarged diameter portion 14c at the tip end of the branch pipe portion 14b. Therefore, the area hit by the steel slag increases as compared with the case where the enlarged diameter portion 14c is not formed. Therefore, the filling degree of the steel slag near the discharge hole 14ba of the pressurized steam formed on the side surface of the branch pipe portion 14b is further lowered, so that the pressurized steam can be efficiently supplied to the center portion of the loaded steel slag. Further, along with this, clogging of the discharge holes 14ba can be further prevented. Further, when the diameter-enlarged portion 14c is formed, the effect of preventing the surface water (lime water) from flowing into the discharge hole 14ba can be further enhanced, so that the clogging of the discharge hole 14ba can be more reliably prevented. Further, it is possible to reduce the physical damage caused by the steel slag loaded by being dropped from above and hitting the main pipe portion 14a.

The size (outer diameter, thickness, and the like) of the enlarged diameter portion 14c is determined to be the optimum size in accordance with the outer diameter d of the branch pipe portion 14b and the position and size of the discharge hole 14ba in the rising direction, so as to achieve the above-described effects. On the other hand, the size or installation position of the discharge hole 14ba can be appropriately determined in accordance with the size of the enlarged diameter portion 14c.

In order to reduce the filling degree of the steel slag in the vicinity of the discharge hole 14ba and prevent clogging of the discharge hole 14ba, and to further improve the steam curing, it is preferable to satisfy one or more of the following conditions. (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 enlarged diameter portion 14c, and d is the branch portion The outer diameter (mm) of 14b, L1 is a separation distance (mm) from the center point of the discharge hole 14ba to the lower end portion of the enlarged diameter portion 14c, and θ is the end point connecting the center point of the discharge hole 14ba and the lower surface of the enlarged diameter portion 14c. The inclination angle (°) from the horizontal line of the line at the position closest to the center point of the ejection hole 14ba in the edge.

The outer diameter and thickness of the main pipe portion 14a and the branch pipe portion 14b, the rising direction and length of the branch pipe portion 14b, the number of installations (the installation interval), and the branch pipe portion are provided in the range in which the effects of the present invention can be obtained. The number and size of the discharge holes 14ba on the side of the 14b are not particularly limited. That is, the outer diameter and the thickness of the main pipe portion 14a and the branch pipe portion 14b are determined according to the following conditions: the amount of pressurized steam to be supplied to the steel slag, and the slag or steel slag which can withstand the loading of the steel slag to be loaded at the time of loading The size of the weight after loading. In addition, the upward direction and the length of the branch pipe portion 14b may be determined in such a manner that the discharge hole 14ba provided in the branch pipe portion 14b is disposed in accordance with the installation position of the slag storage container 11 of the main pipe portion 14a. An appropriate position of the storage area α of the slag storage container 11.

According to the steam-curing apparatus 1 of the above-described embodiment, even when the steel slag having a large proportion of the powder is charged into the slag storage container 11, the filling degree of the steel slag near the discharge hole 14ba can be reduced and prevented. The clogging hole 14ba is blocked. Therefore, the pressurized steam can be efficiently supplied to the center portion of the steel slag charged in the slag storage container 11, and interacts with the pressurized vapor supplied from the first pipe 13 to the inside of the pressure vessel 12, and is carried out in a short time. Steam curing of steelmaking slag. Thereby, the frequency of maintenance of the apparatus can be suppressed, and the aging can be performed efficiently.

The present invention is not limited to the above-described examples, and it is needless to say that the embodiments can be appropriately modified as long as they are within the scope of the technical idea described in the claims.

For example, the number, the number, and the size of the number of the branch portions 14b (the installation interval) and the circumferential direction and the rising direction of the discharge holes 14ba provided in the branch pipe portion 14b are not limited to the examples described in the above embodiments, and It suffices that the pressurized steam can be efficiently supplied to the steel slag located in the center portion of the slag storage container 11.

The branch pipe portion 14b can be erected obliquely in the longitudinal direction X as shown in the first modification shown in Figs. 6A and 6B, and can be erected obliquely in the width direction Z as in the second modification shown in Figs. 7A and 7B. As shown in the third modification shown in FIGS. 8A and 8B, the longitudinal direction X and the width direction Z are inclined to rise. Further, the discharge holes 14ba may be provided in a plurality of places in the height direction Y of the branch pipe portion 14b in the first to third modifications as shown in FIGS. 6A to 8B. When the discharge holes 14ba are provided at a plurality of places, it is preferable that all of the discharge holes 14ba are arranged in a height direction region of 0.3 × H to 0.6 × H of the storage area α.

In the steam curing device 1 of the above embodiment, the second pipe 14 has the enlarged diameter portion 14c, but may not have the enlarged diameter portion 14c. In the steam curing apparatus 1 of the above-described embodiment, the main pipe portion 14a is provided inside the slag storage container 11 along the longitudinal direction X, but may be serpentinely disposed in the width direction Z. That is, the main pipe portion 14a only needs to be disposed along the horizontal direction.

In the steam curing apparatus 1 of the above embodiment, the discharge holes 14ba of all the branch portions 14b are the same size, but may be of different sizes. In the steam curing device 1 of the above-described embodiment, the discharge holes 14ba provided in the branch pipe portion 14b are circular, but the shape of the discharge holes 14ba is not limited to a circular shape, and may be elliptical or polygonal. Further, the branch pipe portion 14b may be provided with a slit.

In the steam curing device 1 of the above-described embodiment, a disk-shaped enlarged diameter portion 14c is provided at the tip end of the branch pipe portion 14b. However, the shape of the enlarged diameter portion 14c may be elliptical or polygonal in plan view. Further, it may not be a plate shape but a conical shape. Further, the position at which the enlarged diameter portion 14c is provided may not be the tip end of the branch pipe portion 14b, and may be higher than the discharge hole 14ba. The steam curing device 1 of the above embodiment has only one main pipe portion 14a. However, the capacity of the slag storage container 11 is increased, and only the pressurized steam discharged from the branch pipe portion 14b provided in the one main pipe portion 14a is used, and the pressurized steam cannot be efficiently supplied to the steel plate to be charged in the slag storage container 11. In the case of the center portion of the slag, the main pipe portion 14a including the branch pipe portion 14b may be plural.

(Example) In the experimental example 1, the steam curing apparatus 1 shown in Fig. 1 was used, and in the experimental examples 2 to 9, the steam curing apparatus was added to the steam curing apparatus 1 to perform steam curing treatment. .

The main common conditions of each experimental example are as follows.・The average particle size of the steel slag: 0-40mm of the road steel slag is used as the particle size of the steel slag. The pressure in the pressure vessel: 0.5MPa ・The height of the storage area H: 1790mm ・The width of the storage area W: 2800mm ・The length of the storage area is L: 6400mm. ・The width direction of the main part: 0.5×W ・The diameter of the main part: 4.5mm ・The steam curing time: 2 hours/cycle ・The amount of steel slag: 45t/cycle in the experimental examples 1~8 A branch pipe portion is erected at four longitudinal positions of 0.25×L, 0.42×L, 0.58×L, and 0.75×L of the main pipe. Further, each branch pipe portion is provided with eight discharge holes at equal intervals in the circumferential direction. Thereby, steam is ejected from 32 discharge holes. On the other hand, in the experimental example 9, as shown in FIG. 10A and FIG. 10B, the branch pipe portion is not provided, but the main pipe portion is provided at the heights of the storage region at the heights of 710 mm and 1530 mm, and each side surface of each main pipe portion is provided. Ten discharge holes arranged in a row along the long side direction are provided at intervals. Thereby, steam is ejected from a total of 40 ejection holes of the two main tubes. In the experiment, in order to carry out the first aging, it is necessary to carry out the step of heating the steel slag into the steam curing apparatus 1 and then heating it to a predetermined temperature, and the step of bringing the steam aging to a predetermined temperature. These processes require a total of one hour. That is, in the experiment, the time required for charging the steelmaking slag into the steam curing apparatus 1 and performing the steam curing treatment and discharging the steelmaking slag from the steam curing apparatus 1 was 3 hours/cycle. On the 1st, the above experiment was carried out 8 times to process 360 tons/day of steelmaking slag. The above-mentioned experiment of 8 cycles and the treatment of 360 tons/day of steel slag were carried out, and the operation was carried out for 1 month, 3 months, and 6 months without stopping the operation.

The individual conditions of each experimental example are shown in Table 1.

[Table 1]

The steel slag which has been subjected to the steam curing treatment described above was subjected to a water immersion expansion test as defined in Attachment B of JIS A 5015 (2013), and the water immersion expansion ratio was measured. The results are shown in Table 2.

[Table 2] a: water immersion expansion test result of steam slag before steam curing: immersion expansion ratio (%) b: immersion expansion test result of steam slag after steam curing: immersion expansion ratio (%) reduction rate: reduction rate = (b/a ) × 100 (%) Initial stage of implementation: The results of the water immersion expansion test performed on the first day of aging slag are carried out one month later: the results of the immersion expansion test of the slag which has been steamed during the operation after one month of daily operation After three months: the results of the water immersion expansion test of the slag that has been steamed in the operation after three months of daily operation are carried out after six months: the slag that has been steam-cooked during the operation after six months of daily operation Water immersion test results

In Experimental Examples 1 to 4, since steam curing was carried out under appropriate conditions, steam ripening can be performed with high efficiency. In particular, in Experimental Examples 1, 2, and 4 in which the enlarged diameter portion was provided, particularly excellent results were obtained as compared with Experimental Example 3 in which the enlarged diameter portion was not provided. It is presumed that this is because the diameter of the steel slag near the discharge hole can be made lower by the diameter-enlarged portion, the occurrence of nozzle clogging can be suppressed, and the pressurized steam can be supplied from the inside of the steel slag as a whole.

In Experimental Examples 5 to 8, steam ripening could not be performed with high efficiency. It is presumed that the discharge holes are not disposed in the height direction region of 0.3×H to 0.6×H, and thus the pressurized steam cannot be sufficiently supplied to the center portion of the slag.

In Experimental Example 9, steam ripening could not be performed with high efficiency. It is presumed that the discharge holes are formed in the main pipe and are disposed in a height direction region higher than 0.6×H. Therefore, the slag discharge holes are clogged, and the main pipe is physically damaged. Further, when the inspection was performed periodically, it was confirmed that the nozzle clogging occurred in the discharge hole. In particular, it is presumed that the nozzle clogging of the discharge hole is to reduce the efficiency of steam ripening.

INDUSTRIAL APPLICABILITY The present invention is not limited to steel slag having a large mixing ratio of powders, and can be applied to steel slag having a particle size of a conventional road substrate.

1‧‧‧Vapor curing unit

11‧‧‧Slag storage container

12‧‧‧ Pressure vessel

12a‧‧‧Open and close cover

13‧‧‧First piping

14‧‧‧Second piping

14a‧‧ ‧ Department of Administration

14b‧‧‧Support Department

14c‧‧‧Extended section

14d‧‧‧Connected pipe department

14ba‧‧‧Spray hole

50‧‧‧Vaporized steam supply device

51‧‧‧ valve

52‧‧‧Pipe

101‧‧‧ moving into the device

102‧‧‧Steel slag

103‧‧‧ slag storage container

104‧‧‧ Pressure vessel

104a‧‧‧Vapor supply port

111‧‧‧A pair of storage components

111a‧‧‧ bottom

111b‧‧‧ first inclined surface

111c‧‧‧ side

111d‧‧‧Second inclined surface

111e‧‧‧ end face

112‧‧‧Support members

112a‧‧‧ pillar

112b‧‧‧Axis

203‧‧‧ slag storage container

204‧‧‧ Pressure vessel

205‧‧‧Pipe

205a‧‧ hole

d, D‧‧‧ OD

H, L, W‧‧‧ size

L1‧‧‧ separation distance

X‧‧‧Longside direction

Y‧‧‧ height direction

Z‧‧‧Width direction

‧‧‧‧Storage area

Θ‧‧‧ tilt angle

Fig. 1 is a schematic front view showing a schematic configuration of a steam curing device according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view taken along line B-B of Fig. 1 and showing a state in which the second pipe is removed. FIG. 3 is a schematic perspective view for explaining the size 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 the main pipe portion and the branch pipe portion. 4C is a schematic view for explaining dimensions of a branch pipe portion and an enlarged diameter portion. Fig. 5A is a schematic view for explaining a discharge state of pressurized steam when the degree of filling of the steel slag near the discharge hole is high. Fig. 5B is a schematic view for explaining a discharge state of pressurized steam when the degree of filling of the steel slag near the discharge hole is low. Fig. 6A is a schematic plan view showing a first modification of the branch pipe portion. Fig. 6B is a schematic front view showing the same modification. Fig. 7A is a schematic plan view showing a second modification of the branch pipe portion. Fig. 7B is a schematic front view showing the same modification. Fig. 8A is a schematic plan view showing a third modification of the branch pipe portion. Fig. 8B is a schematic front view showing the same modification. FIG. 9A is a view for explaining an outline of steam curing using the apparatus proposed in Patent Document 2. Fig. 9B is an enlarged view of the slag storage container of Fig. 9A. FIG. 10A is a side view for explaining a schematic configuration of a pressurized steam curing device proposed in Patent Document 3. FIG. 10B is a plan view illustrating a schematic configuration of a pressurized steam curing device proposed in Patent Document 3.

Claims (10)

A pressurized steam curing device which is a pressurized steam curing device for slag aging of steel slag by pressurized steam, comprising: a slag storage container for loading the steel slag; and a pressure vessel The first sump is disposed outside the pressure vessel for supplying the pressurized vapor to the inside of the pressure vessel; and the second pipe is disposed inside the pressure vessel for The pressurized steam is supplied to the inside of the slag storage container; the second pipe includes a main pipe portion that is provided inside the slag storage container in a horizontal direction, and a branch pipe portion that stands upward from the main pipe portion, and a discharge hole through which the pressurized steam is discharged is formed on a side surface; and when a dimension in a height direction of the storage region of the slag storage container is H (mm), the discharge hole is disposed in the storage area at 0.3×H to 0.6×H. The height direction area. The pressurized steam curing device according to claim 1, wherein the second pipe further includes an enlarged diameter portion above the discharge hole of the branch pipe portion, and the enlarged diameter portion has a larger outer diameter than the branch pipe portion. Outer diameter. The pressurized steam curing device according to claim 2, wherein the enlarged diameter portion is provided at a front end of the branch pipe portion. The pressurized steam curing device according to claim 2 or 3, wherein the outer diameter of the enlarged diameter portion is D (mm) and the outer diameter of the branch portion is d (mm), and D ≧ 2 × d is satisfied. The pressurized steam curing device according to claim 2 or 3, wherein a line connecting the center point of the discharge hole and a position closest to a center point of the discharge hole in the end edge of the lower surface of the enlarged diameter portion is inclined from a horizontal line The angle is below 45°. The pressurized steam curing device according to claim 2 or 3, wherein a separation distance between a lower end portion of the enlarged diameter portion and a center point of the discharge hole is L1 (mm), and an outer diameter of the branch portion is d When (mm), L1≦d is satisfied. The pressure type steam curing apparatus according to any one of claims 1 to 3, wherein when the dimension of the storage area of the slag storage container is L (mm), the discharge hole is disposed in the storage area. A long-side direction region of 0.2 × L to 0.8 × L. The pressure type steam curing apparatus according to any one of claims 1 to 3, wherein, when the dimension of the storage area of the slag storage container is W, the discharge hole is 0.2 × W disposed in the storage area. 0.8 × W width direction area. The pressurized steam curing device according to any one of claims 1 to 3, wherein a plurality of the discharge holes are provided in a circumferential direction of the branch pipe portion. The pressurized steam curing device according to any one of claims 1 to 3, wherein a plurality of the aforementioned portions are disposed in a height direction of the branch pipe portion Spray holes.