JP3370497B2 - Molten slag processing method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a molten slag discharged from a melting furnace which melts incinerated ash and dust individually or in a mixed manner, and rapidly solidifies the molten slag with water to form granulated granulated slag. The present invention relates to a molten slag processing method and apparatus for separately processing crushed slag according to particle size.

[0002]

2. Description of the Related Art Generally, municipal solid waste and industrial waste are incinerated by a stoker furnace or a fluidized bed furnace widely used in a refuse incineration plant to turn into ash, which is reduced in volume, reduced in volume, and rendered harmless. There is.

By the way, in the ash stoker, the ash generated by the incineration of municipal waste is included in the incinerator ash discharged from the end of the stoker and the exhaust gas and captured by the bag filter and the electrostatic precipitator. There is soot and, in a fluidized bed furnace, there is soot contained in exhaust gas and captured by a bag filter or an electrostatic precipitator.

[0004] These ash are greatly reduced in volume and volume as compared with the original trash, and since the perishable organic substances are also lost, even if the trash is directly landfilled, the ash is more than that when landfilled. Since the landfill can be effectively used and is sanitary, most of it has been landfilled.

However, since the incinerated ash and the soot and dust contain harmful substances such as heavy metals and dioxins, there is a possibility that the harmful substances may be eluted after the landfill treatment to cause environmental pollution. In addition, it is becoming difficult to secure landfills year after year, and soot dust has a small particle size among ash and may be scattered in landfills, which causes various problems in practice.

Therefore, in recent years, as a method for solving these problems, melting treatment of ash (incineration ash or dust) has been performed. That is, when the ash is melted and solidified, not only the volume is greatly reduced, but also the substance becomes a physically and chemically stable substance and the elution of harmful substances such as heavy metals is eliminated, and the aggregate and roadbed material Since it can be effectively used for
The above problems can be solved.

Thus, in the conventional ash melting treatment,
Incineration ash and soot and dust are not less than the melting point of ash (usually 1300 ° C to 1500 ° C) by an electric melting furnace such as an arc furnace, a plasma furnace, an electric resistance furnace, or a combustion type melting furnace using a fuel such as oil or gas.
Then, the molten slag is rapidly cooled and solidified with water to form granular granulated slag.

FIG. 6 is a schematic vertical cross-sectional view of a conventional molten slag processing apparatus in which the molten slag discharged from the melting furnace is used as water granulated slag. This molten slag processing apparatus is a molten slag discharge port 20a of the melting furnace 20. Cooling water tank 2 arranged below
1, a duct 22 that connects the molten slag discharge port 20a and the cooling water tank 21 in a communicating manner, and a duct 22 that is disposed in the cooling water tank 21 and has a terminal end located above the water surface and sliding a bottom wall 21a of the cooling water tank 21. And a chain conveyor 24 with a scraper provided with a large number of moving scrapers 23,
The molten slag S discharged from the molten slag discharge port 20a of the melting furnace 20 is dropped from the duct 22 into the cooling water tank 21 and rapidly cooled and solidified by the water W to form granulated granulated slag, which is the bottom wall 21a of the cooling water tank 21. The water granulated slag that has settled to is scraped off by the scraper 23 of the conveyor 24 that slides on the bottom wall 21a, conveyed to the water surface WL, and discharged to the outside from the water granulated slag discharge port 21b of the cooling water tank 21. There is.

In this way, if the molten slag is made into a solid water granulated slag, the volume can be greatly reduced to 30 to 40% compared to ash and 3 to 5% compared to dust. In addition to being advantageous for landfill treatment, it is possible to achieve pollution-free by physically and chemically stabilizing and eliminating elution of harmful substances such as heavy metals. Granulated slag has a high hardness and can be effectively used as a concrete filler material, roadbed material, embankment material, landfill material, block and the like.

When treating the molten slag by the molten slag treatment apparatus, it is desirable that the molten slag S discharged from the melting furnace 20 is continuously discharged in an equal amount. In this case, the molten slag S has a diameter of 2 to 3
The granulated slag has a uniform size and a uniform specific size of 2.5 to 3 mm. Even in this case, light floating ash having substantially the same composition as that of the granulated granulated slag is produced, but since this floating ash is less than 1% of the total amount of slag, the chain conveyor with scraper 24 works. It is discharged naturally and does not hinder the operation of the equipment or the formation of water granulated slag.

[0011]

However, the melting furnace 20
The amount S of molten slag discharged from the molten metal constantly changes due to fluctuations in the amount and composition of ash supplied to the melting furnace 20, and may be large, sharply reduced, or intermittent. or,
Since the melting point changes depending on the composition of ash, the temperature of the molten slag is not uniform.

By the way, when the amount of molten slag S discharged is large and the temperature is high, cooling by water cooling is insufficient and a large amount of floating ash is generated, which amount is 10 to 20 w of the total amount of slag.
It reaches t%. In this way, when a large amount of floating ash occurs,
This floating ash cannot be naturally discharged by the action of the chain conveyor 24 with a scraper, and the water level WL in the duct 22 is reduced.
The molten slag S that stays in the floating state and continues to fall is hindered from cooling. As a result, the amount of floating ash further increases, and eventually the inside of the duct 22 may be blocked.

On the other hand, when the amount of molten slag S discharged is small, the molten slag S is air-cooled and solidified by the time it reaches the water surface WL, which grows to become an icicle, and finally becomes a large lump to form a cooling water tank 21. Will fall inside. As a result, the conveyance and discharge of the water granulated slag by the conveyor 24 is hindered, and the formation of homogeneous and uniformly sized water granulated slag is hindered.

Incidentally, in the conventional molten slag processing apparatus, a water jet injection nozzle 25 is provided in the duct 22,
The injection nozzle 25 injects water to a position where the molten slag S reaches the water surface WL to accelerate the rapid cooling of the molten slag S, but it is difficult to completely solve the above problem only by this measure. It was

Further, in the conventional molten slag processing apparatus, since the water granulated slag that is homogeneous and has a uniform size, the large water granulated slag, and the floating ash are discharged in a mixed state, the water It sometimes hindered the effective use of crushed slag.

The present invention has been made in view of the above problems, and can suppress the amount of floating ash and the agglomeration of granulated slag regardless of fluctuations in the molten metal slag discharge amount and temperature. It is an object of the present invention to provide a molten slag treatment method and apparatus capable of increasing the production rate of homogeneous and evenly sized granulated slag, and also capable of separately treating granulated slag according to particle size.

[0017]

In order to achieve the above object, the method for treating molten slag according to claim 1 of the present invention comprises:
Molten slag discharged from a melting furnace that melts incinerated ash and soot and dust is dropped into a cooling water tank and rapidly solidified by water to form granular water granulated slag.The water granulated slag is placed in the cooling water tank. The crushed slag is separated into large and small water granulated slags, and only the small diameter water granulated slag is allowed to settle on the bottom wall of the cooling water tank, while the large diameter water granulated slag is left in the separation portion to the bottom wall of the cooling water tank. The settled small-diameter granulated slag, the large-diameter granulated slag remaining in the separation part, and the floating ash floating on the water surface are continuously separated from the cooling water tank by a conveyor installed in the cooling water tank. It is characterized in that it is conveyed and discharged.

Further, in the molten slag processing apparatus according to the second aspect of the present invention, the molten slag discharged from a melting furnace for melting incinerated ash and soot and dust is rapidly cooled and solidified with water to form granulated granulated slag. A cooling water tank, a separation unit provided in the cooling water tank, which separates the water granulation slag into small and large by allowing passage of small-diameter water granulation slag, and a cooling water tank which is arranged in the cooling water tank and passes through the separation unit. From a conveyor that continuously conveys and discharges the small-sized granulated slag that settled to the bottom wall of the tank, the large-diameter granulated slag that remains in the separation section, and the floating ash that floats on the water surface, separately from each other in the state of separation. The feature is that it is configured.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an example of a molten slag processing apparatus for carrying out the method of the present invention. The molten slag processing apparatus is attached to a melting furnace 1 for melting and processing ash (incineration ash or soot dust) generated by incineration of municipal waste or the like. Have been,
The cooling water tank 2 arranged below the molten slag discharge port 1a of the melting furnace 1, the granulated slag separation section 3 provided in the cooling water tank 2, and the cooling water tank 2 are arranged and separated. It is composed of granulated slags S ₁ and S ₂ and a conveyor 4 that continuously conveys and discharges the floating ash A floating on the water surface WL to the outside of the cooling water tank 2.

In the melting furnace 1, ash (incinerated ash and soot and dust produced in a stoker furnace and soot and dust produced in a fluidized bed furnace) produced by incineration of municipal solid waste, etc. is incinerated ash alone, soot dust alone or a mixture of both. Above the melting point (usually 1300 ° C-15
The molten slag S is heated to 00 ° C.) to form the molten slag S, and the molten slag S is dropped and discharged from the molten slag discharge port 1a. As the melting furnace 1, an electric melting furnace such as an arc furnace, a plasma furnace, an electric resistance furnace or a combustion type melting furnace using a fuel such as oil or gas is used.

The cooling water tank 2 is disposed below the molten slag discharge port 1a of the melting furnace 1, and the molten slag S dropped and discharged from the molten slag discharge port 1a is rapidly cooled and solidified from the water W to form particles. Granulated slag of

That is, the cooling water tank 2 is formed by a steel plate material into a box-like shape having a rectangular cross section, and the water W for cooling the molten slag S maintains a substantially constant water level inside. It is stored in. Further, the inside of the cooling water tank 2 and the molten slag discharge port 1a of the melting furnace 1 are hermetically sealed by the rectangular tubular steel plate duct 5 connected to the molten slag discharge port 1a and the central portion of the upper wall 2a of the cooling water tank 2. And is discharged from the molten slag discharge port 1a to a high temperature (1300 ° C to 1300 ° C).
The molten slag S of 500 ° C. passes through the duct 5 and falls into the cooling water tank 2. Further, both ends of the cooling water tank 2 are dressed in a slanting manner so that the granulated slag can be discharged onto the water surface WL by the conveyor 4 described later, and one end thereof is provided with a small-diameter granulated slag S ₁ . A small-diameter slag discharge port 2b for discharging, and a large-diameter slag discharge port 2 for discharging large-diameter granulated slag S ₂ and floating ash A at the other end.
c are formed respectively. A seal 6 is provided at the small diameter slag discharge port 2b and the large diameter slag discharge port 2c so that the inside of the cooling water tank 2 is sealed, and a double damper or a slide gate is used for this seal 6. ing.

[0023] The separating unit 3 is provided in the cooling water tank 2, of the water granulated slag of the formed particulate water-cooling, water granulated slag S ₁ to permit the passage of small diameter water granulated slag S _1,
S ₂ is divided into large and small, and a horizontal sorting portion 3 ′ provided below the water surface WL of the cooling water tank 2 below the duct 5 and over the entire width of the cooling water tank 2 and a large-diameter slag discharge of the cooling water tank 2. The cooling water tank 2 is provided with an inclined separating portion 3 ″ provided over the entire width of the cooling water tank 2 in the inclined portion toward the outlet 2c.

That is, as shown in FIGS. 2 and 3, the separating portion 3 (horizontal separating portion 3'and inclined separating portion 3 ") has a cross-sectional shape formed of mild steel, stainless steel, other metal material or ceramic material. Inverted trapezoidal bars 3a are arranged in parallel along the longitudinal direction of the cooling water tank 2 at regular intervals, and a plurality of rows are also arranged in the width direction of the cooling water tank 2, with water granulation having a small diameter between the bars 3a. It is configured by forming a large number of slits 3b that allow passage of the slag S _1. Each bar 3a in the first row of the sorting unit 3 is provided with a gap having the same width as the bar 3a to provide a cooling water tank. 2 arranged side by side in the longitudinal direction, and each bar 3 in the second row
a is juxtaposed at the same interval as the bar 3a in the first row and in a state of discrepancy with the bar 3a in the first row, and each bar 3a in the third row is the same as the bar 3a in the first row. The rods 3a are arranged side by side, and the rods 3a in the fourth and subsequent rows are also arranged in the same manner as above. In addition, the width of the slit 3b of the separation part 3 should be 10 mm or less because a granulated slag having a diameter of several mm or less can be obtained when the amount of the molten slag S discharged from the melting furnace 1 is always equal. However, in this example, the width of each slit 3b is 5 mm to 10 mm. Further, the depth H ₁ from the water surface WL to the bar 3a in the horizontal sorting part 3 ′ is
Molten slag S discharged from the molten slag discharge port 1a
Is selected so that the granulated slag can be produced reliably and satisfactorily.

The conveyor 4 has a small-diameter granulated slag S ₁ that has passed through the sorting section 3 and settled on the bottom wall 2d of the cooling water tank 2, a large-sized granulated slag S ₂ remaining in the sorting section 3, and the water surface WL. The floating ash A floating in the air is continuously conveyed and discharged to the outside of the cooling water tank 2 in a separated state. In this example, a chain conveyor 4 with a scraper is used as the conveyor 4.

That is, the conveyor 4 has a drive sprocket 8 rotatably disposed in the cooling water tank 2 and above the large-diameter slag discharge port 2c via the drive shaft 7, and the cooling water tank 2
It is rotatably disposed between the driven idler 10 which is rotatably disposed inside the upper portion of the small diameter slag discharge port 2b through the driven shaft 9 and the horizontal portion and the inclined portion of the cooling water tank 2. It is wound between the intermediate idler 11, the drive sprocket 8 and the driven idler 10, below the water surface WL above the horizontal sorting section 3 ', above the tilt sorting section 3 ", below the tilt sorting section 3", and horizontally. The lower position of the separation part 3'and the water surface W
An endless chain 12 extending from the L upper position to below the water surface WL above the horizontal sorting section 3 ', and attached to the chain 12 at regular intervals, sliding on the sorting section 3 and the bottom wall 2d of the cooling water tank 2. Separated granulated slag S ₁ , S ₂ and water surface WL
Scraper 13 for scraping and transporting floating ash A
And a drive source (not shown) such as a motor which is disposed outside the cooling water tank 2 and rotationally drives the drive sprocket 8.

In the upper part of the conveyor 4, the scraper 13 slides on the bar 3a of the separating part 3 and floats on the large-sized granulated slag S ₂ remaining in the separating part 3 and the water surface WL. In addition to scraping and transporting the floating ash A, the scraper S ₁ having a small diameter that slides on the bottom wall 2d of the cooling water tank 2 at the lower part of the conveyor 4 and settles on the bottom wall 2d is transported. Is. The scraper 13 is made of mild steel, stainless steel,
The channel 12 is made of other metal material or ceramic material and has a U-shaped cross section. It is attached to the chain 12 at regular intervals so that the open portion faces the traveling direction so as to improve the transportation efficiency. Has been.
In addition, the mounting interval of the scraper 13 to the chain 12 is appropriately selected according to the amount and properties of the molten slag S, the load state of the melting furnace 1, and the like. Further, the length of the scraper 13 is substantially the same as the width of the cooling water tank 2, and the height H ₂ of the scraper 13 is such that the scraper 13 slides on the bar 3a of the horizontal sorting section 3 '. When you do, the upper end is the water surface WL
Are selected so as to protrude by 50 mm to 100 mm. As a result, the scraper 13 can scrape and convey not only the granulated slag remaining in the horizontal sorting section 3 ', but also all the floating ash A floating on the water surface WL. In this example, the scraper 13 has a height of 20
It is selected to be 0 mm to 300 mm.

Next, the case where the molten slag S is processed by using the molten slag processing apparatus configured as described above will be described. The molten slag discharged and discharged from the molten slag discharge port 1a of the melting furnace 1 falls into the cooling water tank 2 through the duct 5 and is rapidly solidified by the water W on the horizontal separation section 3'to form granular granulated slag. Become.

Since most of the granulated slag has a higher specific gravity than ordinary water and a diameter of several mm or less, it falls into the water and reaches the horizontal separation section 3 ', and the horizontal separation section 3' It passes through the slits 3b and sinks to the bottom wall 2d of the cooling water tank 2. At this time, the small-diameter granulated slag S ₁ remaining on the bar 3a of the horizontal sorting section 3'is scraped in the traveling direction of the conveyor 4 by the scraper 13 sliding on the bar 3a of the horizontal sorting section 3 '. Then, it enters the slit 3b and falls from here to the bottom wall 2d of the cooling water tank 2. In addition, the large-diameter granulated slag S ₂ that does not pass through the slit 3b has a part of the slit 3b.
It enters and is sheared and broken by the cooperation of the scraper 13 and the bar 3a. The granulated slag S _{1 which} has been shattered to have a small diameter passes through the slit 3b and settles on the bottom wall 2d of the cooling water tank 2.

Since the slits 3b are formed in a plurality of rows in the width direction of the cooling water tank 2, the granulated slag S ₁ having a small diameter is dropped through any of the slits 3b into the cooling water tank regardless of the position in the sorting section 3 where it falls. As a result, the small-sized water granulated slag S ₁ is less likely to be mixed into the large-diameter water granulated slag S ₂ . Further, since the slit 3b is formed by using the bar 3a having an inverted trapezoidal cross section, the slit 3b has a wider interval as it goes downward. As a result, the slits 3b are less likely to be clogged, and the small-diameter water granulated slag S ₁ can be passed reliably and satisfactorily. Further, since the bar 3a has an inverted trapezoidal cross-section, it is possible to more reliably and satisfactorily shear the large-diameter granulated slag S ₂ by the cooperation of the scraper 13.

The granulated slag S ₁ settled on the bottom wall 2d of the cooling water tank 2 is scraped by the scraper 13 sliding on the bottom wall 2d.
Are scraped off and transported to the water surface WL, and discharged from the small diameter slag discharge port 2b through the seal 6 to the outside of the cooling water tank 2.

On the other hand, the large-diameter granulated slag S ₂ that does not pass through the slits 3b of the horizontal sorting section 3'and the soft floating ash A that does not settle in the water W are scrapers 13 that continuously pass through the horizontal sorting section 3 '. The bar 3a of the inclined separation part 3 ″ is scraped off by the
It is conveyed on the water surface WL while moving up, and is discharged from the large diameter slag discharge port 2c through the seal 6 to the outside of the cooling water tank 2. At this time, the large-diameter granulated slag S ₂ slides on the bar 3a of the inclined sorting part 3 ″ even when passing over the inclined sorting part 3 ″, and the bar material of the inclined sorting part 3 ″. Shear fracture due to the cooperative action with 3a, and horizontal separation section 3 '.
Granulated slag S _{1 of} small diameter that did not pass through the slit 3b
Also, when it passes through the inclined sorting portion 3 ″, it falls from the slit 3b to the bottom wall 2d of the cooling water tank 2.

In this way, the molten slag S that has fallen into the cooling water tank 2 is cooled and solidified by water to become granular water granulated slag. This water granulated slag is slag S _{1 having a} small diameter by the separating section 3. Large-sized granulated slag S containing ash and floating ash A
It is separated into ₂ and is continuously and quickly conveyed and discharged separately from the cooling water tank 2 by the conveyor 4.

This molten slag processing apparatus can suppress the amount of floating ash and the agglomeration of granulated slag regardless of the amount of molten slag S discharged and the fluctuation of the temperature. The production rate can be increased.

That is, when a large amount of high-temperature molten slag S is dropped and discharged from the molten slag discharge port 1a of the melting furnace 1, the small-diameter granulated slag S ₁ produced in the cooling water tank 2 is
The scraper 1 of the conveyor 4 that sinks to the bottom wall 2d of the cooling water tank 2 through the slits 3b of the separation unit 3 and slides on the bottom wall 2d.
3 is discharged from the small diameter slag discharge port 2b. Further, of the large-diameter granulated slag S ₂ , a relatively small one is partially sheared into the slit 3b and sheared by the cooperative action of the scraper 13 and the rod 3a sliding on the rod 3a of the separating part 3. It will be destroyed and a part of it will fall from the scraper 13. Then, the large-diameter granulated slag S ₂ which has not been sheared and the floating ash A generated near the lower part of the duct 5 due to incomplete water cooling are quickly scraped off by the scraper 13 passing through the horizontal sorting part 3 ′. Transported, cooling water tank 2
It is discharged from the large diameter slag discharge port 2c. As a result, the floating ash A and the like stay on the horizontal separation section 3 ′ and do not impede the water cooling of the molten slag S that is continuously dropped and discharged, and does not promote the increase and accumulation of the floating ash A. . Therefore, the generation rate of the floating ash A does not increase, and the lower part of the duct 5 is not blocked by the floating ash A.

On the other hand, when the load of the melting furnace 1 is reduced and the drop discharge amount of the molten slag S is reduced, the molten slag S is cooled and solidified by air cooling and becomes an icicle in the duct 5, but the horizontal separation is performed. The scraper 13 of the conveyor 4 moving on the portion 3'quickly scrapes off the icicle-shaped slag and conveys it to the large-diameter slag discharge port 2c side. As a result, it is possible to prevent the icicle-shaped slag from growing into a large slag in the duct 5, and it is possible to cool the subsequently falling molten slag S with the water W, so that the slag is homogeneous. Granulated slag of uniform size can be formed.

FIG. 4 shows another example of the molten slag processing apparatus for carrying out the method of the present invention.
A chain guide body 14 such as an intermediate idler or a guide plate is provided at both ends of the horizontal sorting portion 3'to allow the scraper 13 to be temporarily submerged at both ends of the horizontal sorting portion 3'and the duct 5
The lower end portion of the cooling water tank is inserted below the water surface WL to form a water sealing structure, and the large diameter slag discharge port 2c and the small diameter slag discharge port 2 of the cooling water tank 2 are inserted.
The seal 6 provided in b is omitted, and other configurations are the same as those of the molten slag processing apparatus.

This molten slag processing apparatus can also achieve the same operational effects as the molten slag processing apparatus of the above example (shown in FIG. 1). In addition, this molten slag processing device,
Since the lower end of the duct 5 is inserted below the water surface WL to seal the inside of the duct 5 with water, the seal 6 provided at the large diameter slag discharge port 2c and the small diameter slag discharge port 2b of the cooling water tank 2
Can be omitted.

In each of the molten slag processing devices (shown in FIGS. 1 and 4), a water jet injection nozzle 15 is provided in the duct 5, and the molten slag S reaches the water surface WL from the injection nozzle 15. Injecting water to the position, molten slag S
May be accelerated. In this case, generation, increase and accumulation of floating ash A can be further suppressed. Further, in each of the molten slag processing devices, a water washing nozzle (not shown) is provided above the slant separation part 3 ″ on the side of the large-diameter slag discharge port 2c so that the slant separation part 3 ″ has a bar 3a above it. it may be the water jet from the washing nozzles in the water granulated slag S ₂ of large diameter being transported, wash water granulated slag S ₁ of a small diameter attached to the water granulated slag S ₂ large diameter .

In each of the above examples, the bar members 3a are arranged side by side at regular intervals, and the slits 3b are formed between the bar members 3a to form the granulated slag separating portion 3. The configuration of the separation unit 3 is not limited to the above example, and if the water granulated slag can be separated into large and small,
It may have any structure. For example, a steel plate formed with a large number of slits 3b may be arranged below the water surface WL of the cooling water tank 2 to form the separation unit 3, or a wire mesh made of steel or a punching metal plate made of a steel plate may be used as the cooling water tank. Two
The sorting unit 3 may be arranged below the water surface WL.

In each of the above examples, the bar members 3a are arranged in parallel along the longitudinal direction of the cooling water tank 2 at regular intervals, and a plurality of rows are also arranged in the width direction of the cooling water tank 2 so that the separating portion 3 Although the slits 3b have a multi-row structure, in another example, the rods 3a having the same width as the cooling water tank 2 are arranged in parallel along the longitudinal direction of the cooling water tank 2 at regular intervals to form the slits 3b. You may make it a single line structure. Moreover, as shown in FIG.
V-shaped slits are arranged side by side at regular intervals along the longitudinal direction of the cooling water tank 2 to form a V-shaped slit 3b having a single-row structure or a V-shaped slit 3b having a multi-row structure. You can

In each of the above examples, the width of the slit 3b is set to 5 mm to 10 mm. However, since the diameter of the granulated slag varies depending on the properties of the molten slag S, the water temperature, etc., the width of the slit 3b is 7 mm to 15 mm. Also good.

In each of the above examples, the sorting unit 3 is composed of a horizontal sorting unit 3'and an inclined sorting unit 3 ", and both sorting units 3 ',
Although the 3 "has the same structure so that the water granulation slag can be separated also in the inclined separation part 3", if the water separation slag can be completely separated only in the horizontal separation part 3 ', the inclined separation part 3 "
May be omitted. In this case, guide plate for the lower surface and the sliding of the scraper 13 over the end of the horizontal separating unit 3 'in diameter slag discharge port 2c (not shown) arranged, a large-diameter water granulated slag S ₂ and浮灰A Must not fall onto the bottom wall 2d of the cooling water tank 2.

In each of the above examples, the scraper 13 is
Although the cross-sectional shape formed of mild steel or the like is composed of a channel material having a U-shape, the shape and structure of the scraper 13 are not limited to this. For example, scraper 1
3 may be formed of a channel material having an L-shaped cross section, or the scraper 13 may be formed of a slender rectangular wire mesh or a punching metal plate so that draining can be performed well.

In each of the above examples, one chain conveyor 4 with scraper is used to separately convey and discharge the small-diameter granulated slag S ₁ and the large-diameter granulated slag S ₂ mixed with the floating ash A. In other examples, though not shown,
Two chain conveyors 4 with scrapers in the cooling water tank 2
Are arranged above and below, and the large-diameter granulated slag S ₂ and floating ash A on the separating section 3 are conveyed and carried out by the upper conveyor 4, and the small diameter settled on the bottom wall 2d of the cooling water tank 2 by the lower conveyor 4. The water granulated slag S ₁ may be carried out.

[0046]

As is apparent from the above description, according to the present invention, molten slag is rapidly cooled and solidified with water to form granulated slag, and the granulated slag is fractionated into large and small granulated slag by a fractionation unit. However, since the separated small-diameter granulated slag, large-diameter granulated slag, and floating ash floating on the water surface are continuously and quickly conveyed and discharged by the conveyor, the amount of molten slag discharged and the temperature Regardless of fluctuations, it is possible to prevent the growth and retention of floating ash and the agglomeration of slag. As a result, it is possible to increase the production rate of granulated slag that is homogeneous and of uniform size, and eliminate the blockage accidents due to the accumulation of large slag and floating ash, etc., and to continuously and stably process molten slag. it can. In addition, the granulated slag is separated according to the particle size, and the separated small-diameter granulated slag, large-diameter granulated slag, and floating ash floating on the water surface are separately conveyed and discharged. Post-treatment of slag can be done easily and easily. That is, the small-sized granulated slag that has been separated and collected can be reused as it is as a valuable material such as a concrete filler material, and the large-diameter granulated slag and floating ash are generated. Since the amount is small, landfill processing is possible. Needless to say, the large-sized water granulated slag can be reused by crushing it and mixing it with the small-diameter water granulated slag.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing an example of a molten slag processing apparatus for carrying out the method of the present invention.

FIG. 2 is an enlarged vertical sectional view of a main part of the molten slag processing apparatus.

FIG. 3 is a transverse cross-sectional view showing a part of a separation unit of the molten slag processing apparatus.

FIG. 4 is a schematic vertical sectional view showing another example of the molten slag processing apparatus.

FIG. 5 is a cross-sectional view showing another example of the sorting unit.

FIG. 6 is a schematic vertical sectional view of a conventional molten slag processing apparatus.

[Explanation of symbols]

1 is a melting furnace, 2 is a cooling water tank, 2d is a bottom wall, 3 is a separation part,
4 is a conveyor, S is a molten slag, S ₁ is a small diameter granulated slag, S ₂ is a large diameter granulated slag, A is floating ash, W is water, and WL
Is the water surface.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-53-223 (JP, A) Fukukaihei 2-61942 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) C04B 5/00

Claims (2)

(57) [Claims] 1. A molten slag (S) discharged from a melting furnace (1) for melting incinerated ash or soot and dust is dropped into a cooling water tank (2) and rapidly cooled and solidified with water (W) to form a granular form. The granulated slag is divided into large and small granulated slags (S ₁ ) and (S ₂ ) by the granulated slag separation section (3) provided in the cooling water tank (2), and water of small diameter is formed. Only the crushed slag (S ₁ ) is allowed to settle on the bottom wall (2d) of the cooling water tank (2), and the large-sized water crushed slag (S ₂ ) is left in the separation section (3) to leave the bottom of the cooling water tank (2). Small-diameter granulated slag (S ₁ ) settling on the wall (2d), large-diameter granulated slag (S ₂ ) remaining in the separation part (3), and floating ash (A) floating on the water surface (WL) And are continuously separated and discharged by the conveyor (4) arranged in the cooling water tank (2) to the outside of the cooling water tank (2). A method for treating molten slag, characterized in that 2. A cooling water tank (2) in which molten slag (S) discharged from a melting furnace (1) for melting incineration ash and soot and dust is rapidly cooled and solidified with water (W) to form granular granulated slag.
And the water granulation slag (S ₁ ), which is provided in the cooling water tank (2) and allows passage of the small diameter water granulation slag (S ₁ ),
The separation section (3) for separating (S ₂ ) into large and small parts is arranged in the cooling water tank (2), and the particles pass through the separation section (3) and settle on the bottom wall (2d) of the cooling water tank (2). Small diameter granulated slag (S
₁ ) and large diameter granulated slag (S ₂ ) remaining in the separation section (3)
And a floating ash (A) floating on the water surface (WL) and a conveyor (4) that continuously conveys and discharges the floating ash (A) to the outside of the cooling water tank (2), respectively. .