JP2002349839A - Melt discharge port of melting furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a melt discharge port of a melting furnace which is capable of continuously more smoothly discharging melt such as slag, molten metals, etc., produced in a waste gasifying melting furnace or incineration ash melting furnace from the furnaces to a recovery apparatus than the conventional one. SOLUTION: The melt discharge port of a melting furnace comprises a passage provided in a lower part of the melting furnace for flowing melt in a direction perpendicular to the furnace axis, a cylindrical shoot formed with a water-cooled jacket for vertically dropping down the melt from the top end of the passage, a plurality of water jet nozzles disposed below the shoot for jetting cooling water on the melt and a melt recovery tank disposed below the shoot. The jacket uses a copper-made water cooled jacket having a half- segmental shape in plan view and may be used on a region nearer to the flow passage only or the water jet nozzles are more preferably those jetting the cooling water at a pressure of 980 kPa or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melt discharge port of a melting furnace, and more particularly, to a method of discharging slag, metal, and the like generated by a waste gasification and melting apparatus and an incineration ash melting apparatus.
The present invention relates to a technique for smoothly and continuously discharging from these furnaces to a recovery device.

[0002]

2. Description of the Related Art At present, industrial waste and general waste (hereinafter referred to as "waste")
(Collectively referred to simply as waste) has a remarkable shortage of disposal sites, and most of them have been subjected to final disposal such as landfill after being reduced in volume by incineration. In recent years, from the viewpoint of management of harmful substances such as dioxin in generated gas in incineration plants and resource recycling, not only incineration of waste but also technology of recovering it as fuel gas or chemical raw material gas has emerged. . For example, as shown in FIG. 1, a "chemical apparatus" (issued by the Industrial Research Council of July 1998) compresses and reduces the volume of a waste 1 with a press 2 and then a pyrolysis furnace 3
There is proposed a waste pyrolysis gasification / melting apparatus including a high temperature reactor 4, a melt homogenization furnace 5, a gas cooling device 6, a purification device 7, a water treatment device 8, and the like.

In the incineration ash melting furnace and waste pyrolysis gasification melting apparatus described above, the generated melt is usually continuously discharged from an outlet provided at one end of the furnace lower part.
It is configured to drop vertically downward into a water tank 9 (recovery tank) provided below. Further, in consideration of the convenience of subsequent handling, the molten material 10 is rapidly cooled by blowing cooling water at a pressure of 490 kPa (about 5 kgf / cm ² ) or less through the water injection nozzle 11 during the vertical drop, and (This technique is called granulation, for example,
JP-A-55-102815, JP-A-61-243
No. 893, Japanese Utility Model Application Laid-Open No. 62-162243, etc.).

However, in the above-described discharge technique, the molten material that falls from a place where the granulated water is not sprayed (near the wall of the flow path) is icicle-like from the drop start position of the drop to the vertical wall below it. It becomes a coagulated product (hereinafter simply referred to as "icicle"), and when the "icicle" becomes thicker, it extends to the portion where the granulated water is sprayed (the center of the flow channel). The thickened “icicles” cannot be destroyed by the granulated water, so they grow further and completely close the opening. This phenomenon is remarkable when the flow rate of the melt is large. Incidentally, blockage occurs within 20 to 30 hours after the start of operation. For this reason, the operation of stopping the operation and manually removing the solidified matter is usually performed.

[0005] In addition, just as water flows in several flow paths in the shallows of a river, the falling position of the melt is not constant, so that water cannot be reliably sprayed on the melt.
In some cases, the growth of "icicles" is promoted. Furthermore, if the amount of water is increased so that granulated water is always applied to the entire melt, the temperature of the melt decreases near the mouth, or the wall surface temperature of the mouth decreases due to the steam generated from the granulated water, There was also a problem that the melt solidified near the drop. Heating the melt using a gas burner just before the drop is performed so that the melt does not solidify just before the drop, but has a drawback that fuel cost increases. In addition, the "icicle"
Although it is conceivable to mechanically knock down and destroy it, it is not clear what destruction device is suitable, and there is no practical application.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention is directed to a method in which molten materials such as slag and metal generated in a waste gasification and melting apparatus and an incineration ash melting apparatus are transferred from these furnaces to a recovery apparatus. An object of the present invention is to provide a melt discharge port of a melting furnace that can be discharged smoothly and continuously.

[0007]

Means for Solving the Problems In order to achieve the above object, the inventor has conducted intensive studies on the melt outlet, and has embodied the results in the present invention.

That is, the present invention is provided with a flow path provided in a lower part of a melting furnace and flowing a melt in a direction perpendicular to a furnace axis, and a water cooling jacket, and the melt falls vertically from a tip of the flow path. A cylindrical drop to be formed, a plurality of water injection nozzles provided on the vertical wall of the cylindrical drop and spraying cooling water on the melt, and a recovery of the melt disposed below the cylindrical drop A melt discharge port of the melting furnace, characterized in that a copper water-cooled jacket is used for the water-cooled jacket at the melt discharge port of the melting furnace having a bath.

In this case, it is more preferable that the copper water-cooling jacket is formed in a semi-cut shape in a plan view and is used only near the flow path side, or that the water injection nozzle injects cooling water at a water pressure of 980 kPa or more. good. It is also preferable that the tip of the water injection nozzle is swingable. Furthermore, a coagulated material destruction device that impacts the coagulated material attached to the vertical wall to break and drop the coagulated material below the water jet nozzle installation position on the wall of the cylindrical drop is provided. More preferred. As a concrete breaking device, a slide type chopper or a piston type crusher is preferable. In addition, it is preferable that the melting furnace is a furnace for melting incineration ash or waste.

According to the present invention, a slag, a metal, or the like generated in a waste gasification / melting apparatus or an incineration ash melting apparatus can be continuously and smoothly discharged from these furnaces to a recovery apparatus. become.

[0011]

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

First, the configuration of a conventional melt discharge port will be described by taking a waste pyrolysis gasification melting apparatus as an example. that is,
It is provided at one end of a melt homogenization furnace 5 (this corresponds to a melting furnace in the present invention) provided below the high temperature reactor 4 shown in FIG. 1 (portion surrounded by a broken line in FIG. 1). . That is, a cylindrical flow path 12 (see FIG. 2A) through which the melt flows in a direction orthogonal to the furnace axis of the homogenization furnace 5 is formed. A gas burner 13 for heating the normally flowing melt is provided on the ceiling of the flow channel 12 as shown in FIG. The flow path 12 has an inner diameter of about 1000 mmφ, and its bottom surface is often inclined so that the melt 10 flows easily. Then, at the tip of the flow channel 12, FIG.
As shown in (c), a cylindrical drop 14 for dropping the melt vertically downward is provided. The opening 14 has an inner diameter of about 800 mmφ, which is smaller than the flow path 12,
The length of the vertical wall is usually about 10 m. On the vertical wall 15 of the entrance 14, the molten material 10 falling along the circumference thereof
Are provided with a plurality of water jet nozzles 11 for spraying water. Further, a collecting tank 9 (usually a water tank) is provided below the outlet 14 in order to collect the solidified material which has been rapidly cooled with water and turned into fine particles.

In such a conventional melt outlet, since the refractory of the drop 14 is melted and damaged by the melt 10 in about 10 days from the start of the operation during the operation, the operation is stopped and the refractory 1
6 must be repaired. The repair of the refractory 16 requires a period of three days or more including drying, and there is a problem that the pyrolysis gasification and melting apparatus cannot be operated during this period.

For this reason, the inventor of the present invention has made the outlet 14 a steel water-cooled jacket 17 (heat conductivity: 56 W) as shown in FIG.
/ M / K), and the refractory 16 is applied thereon. However, steel still has low thermal conductivity,
The refractory could not be cooled sufficiently, the refractory melted and the steel was exposed, and the iron in the melt adhered to the exposed steel and grew to close the pit. The period until the blockage was about 18 days, which was somewhat improved compared to the case of using only the refractory, but the operation was still not satisfactory.

The present invention has been conceived to improve such a situation. As shown in FIG. 4, a water cooling jacket 18 made of copper (thermal conductivity: 381) is provided on the water cooling jacket 17 as shown in FIG.
W / m / K). Since copper has a high thermal conductivity, slag adheres thinly to the surface of the water-cooled jacket, and is used as a substitute for a refractory, so that it is not necessary to consider the erosion of the refractory. However, if the opening structure is as shown in FIG. 4, it cools down to a portion B (shown by a dotted line in the figure) where the melt does not flow. As described above, the flow path 12 is connected to the gas burner 13 (LNG usage: 100 Nm ³ /
It is economically wasteful to cool to an unnecessary part by adopting a copper cooling jacket while keeping the heat at hr).

Therefore, in the present invention, as shown in FIG.
The copper water-cooled jacket 18 was formed in a semi-cut shape in a plan view, and was provided only near the portion where the melt 10 flows (the side connected to the flow path) at the opening. As a result, the amount of LNG used in the gas burner 13 for keeping the flow path 12 heat was reduced to 80 Nm ³ / hr. However, the coagulate gradually grows in the drop 14, thereby causing a problem that the drop is closed in about 45 to 50 days after the start of the operation. Although this has been considerably improved as compared with the related art, it was necessary to stop the operation for one day or more to remove the coagulated matter that caused the blockage, in order to eliminate the blockage.

The inventor has continued to pay attention to the pressure of the cooling water sprayed on the melt in order to further extend the period up to the above-described opening closure. In other words, it was thought that if high-pressure water is applied to the melt before the solidified product grows thick, the solidified product can be broken. Then, the water injection nozzle 11 was changed to one capable of injecting higher-pressure water, and the operation was performed with various changes in the pressure of the cooling water.

As a result, when the water pressure is 490, 686, 883
When the pressure was set to kPa, the solidified material could not be prevented from growing thickly. By setting the pressure to 980 kPa or more, the solidified material did not grow thickly gradually, and the period could be extended to about 70 days. For this reason, in the present invention, a water jet nozzle (hereinafter simply referred to as a nozzle) 11 that can make the pressure of the cooling water 980 kPa or more is adopted.

However, since the melt 10 flows in a meandering manner in the flow path 12, the drop 1 having a smaller diameter than the flow path 12 is formed.
It is unknown where in FIG. 4 the melt 10 begins to fall.
Therefore, it was necessary to always apply cooling water at a pressure of 980 kPa or more to the entire surface of the exit wall. This causes another problem that the amount of cooling water increases more than before, and the temperature in the flow path 12 decreases due to the effect of water evaporation.
3 increased the amount of LNG used.

Therefore, the pressure of the cooling water from the nozzle 11 was set to 980 kPa, and the nozzle 11 was improved so that its tip could swing right and left and up and down as shown in FIG. In FIG. 6, the swingable range is shown by encircling the nozzle 11. As a result, cooling water can be reliably sprayed only on the flow of the falling melt, and useless cooling water can be avoided to prevent the growth of solidified material. By the way, the amount of cooling water from the nozzle 11 could be reduced to 1/16 compared with the conventional case. Also,
The LNG amount of the gas burner 13 for keeping the flow passage heat was also reduced. However, still, the problem that the solidified material gradually grows and becomes "icicles" and closes the opening 14 could not be completely solved.

For this reason, the inventor decided to mechanically break the "icicle" and drop it.

As shown in FIG. 7, the apparatus is of a slide chopper type formed by a hydraulic cylinder 19, a chopper 20, and a support rod 21. When the operation was performed using this apparatus in combination, the time required for closing the outlet 14 with the solidified material could be extended to about 132 days. However, the discharge amount of the melt 10 was not stable, and when a large amount of the melt was rapidly discharged, the apparatus shown in FIG. 7 was insufficiently broken.

In such a case, the inventor of the present invention has developed a piston crusher-type apparatus having a hydraulic cylinder 19 and a piston 22 as shown in FIG. Also tried to use. As a result, the solidified material that could not be broken and dropped by the apparatus shown in FIG. 7 can be dropped, and the time required to close the opening 14 can be extended to 150 days or more.

In this case, the mechanical destruction device is preferably installed 5 cm to 100 cm below the position where cooling water is applied to the melt. If it is less than 5 cm, the cooling water will bounce off with a tapping device, lowering the temperature of the drop and promoting the solidification of the melt near the drop. If it is more than 100 cm, the melt will grow icicle-like. This is because it is difficult to mechanically knock it down. In the present invention, the piston type crusher may be installed below the slide type chopper and used together.

To clarify the above, the contents are shown in Table 1 collectively. From Table 1, it is clear that the outlet that had been closed in about 10 days from the start of the operation does not become blocked until 150 days or more by employing the outlet according to the present invention.

[0026]

[Table 1]

[0027]

As described above, according to the present invention, the frequency of closing the melt outlet of the melting furnace is reduced, and the slag, metal, etc. generated in the waste gasification and incineration ash melting apparatus are reduced. The melt can be smoothly and continuously discharged from these furnaces to the recovery device as compared with the conventional method.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a waste pyrolysis gasification melting apparatus.

FIG. 2 is a view for explaining a conventional melt discharge port;
(A) is the front, (b) is the side, and (c) is the plane.

FIG. 3 is a view showing a conventional discharge port in which the outlet of the melt is made of a steel water-cooled jacket.

FIG. 4 is a view showing a melt outlet according to the present invention in which the outlet of the melt is a copper water-cooled jacket.

FIG. 5 is a plan view showing a state in which the copper water-cooled jacket according to the present invention is cut in a half shape in plan view.

FIG. 6 is a diagram showing a swing range of a tip of a water injection nozzle,
(A) is the front of the outlet, and (b) is the side.

FIGS. 7A and 7B are diagrams showing a state in which a slide / chopper-type coagulated matter breaking device is attached to an outlet, where FIG. 7A is a front view of the outlet, FIG. 7B is a side view, and FIG.

8A and 8B are views showing a state in which a piston crusher type coagulated matter breaking device is attached to an outlet, FIG. 8A is a front view of the outlet, FIG. 8B is a side view, and FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Waste 2 Press 3 Pyrolysis furnace 4 High-temperature reactor 5 Homogenization furnace (melting furnace) 6 Cooling device 7 Purification device 8 Water treatment device 9 Water tank (recovery tank) 10 Melt 11 Water injection nozzle (nozzle) 12 Flow Road 13 Gas burner 14 Outlet 15 Vertical wall 16 Refractory 17 Steel water cooling jacket 18 Copper water cooling jacket 19 Hydraulic cylinder 20 Chopper 21 Support rod 22 Piston

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // F23G 5/027 ZAB F23G 5/027 ZABZ F term (reference) 3K061 AA23 AB02 AB03 AC01 FA02 NB01 NB15 NC03 4K050 AA07 BA06 CA05 CA11 CG26 4K051 AA00 AB05 HA06 4K055 AA00 JA17

Claims (7)

[Claims] 1. A flow path provided in a lower part of a melting furnace, through which a melt flows, a cylindrical cooling hole formed by a water-cooled jacket, and vertically dropping the melt from a tip of the flow path; A melt discharger for a melting furnace having a plurality of water injection nozzles provided on a vertical wall of a mouth for spraying cooling water onto the melt and a melt recovery tank disposed below the cylindrical outlet. At the outlet, a melt outlet of the melting furnace, wherein a water cooling jacket made of copper is used for the water cooling jacket. 2. The molten metal discharge port of a melting furnace according to claim 1, wherein the copper water-cooled jacket is formed in a semi-cut shape in a plan view, and is used only near the flow path side. 3. The melt outlet of a melting furnace according to claim 1, wherein said water injection nozzle injects cooling water at a water pressure of 980 kPa or more. 4. The melt outlet of a melting furnace according to claim 1, wherein a tip of said water injection nozzle is swingable. 5. A coagulated material destruction device for applying a shock to the coagulated material attached to the vertical wall to break and drop the coagulated material below the installation position of the water jet nozzle on the wall of the cylindrical drop. The melt outlet of the melting furnace according to any one of claims 1 to 4, wherein: 6. The melt discharge port of a melting furnace according to claim 5, wherein the coagulated material breaking device is a slide type chopper or a piston type crusher. 7. The melt outlet of a melting furnace according to claim 1, wherein the melting furnace is a furnace for melting incineration ash or waste.