JP2003120923A - Fusing apparatus for ash - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of frequently causing permanent set in fatigue of a crucible 4 in the center and cracks due to stress strain in the vertical direction due to dead load when an apparatus is heated to a high temperature as much as 1,600 to 1,650 deg.C. SOLUTION: This apparatus adopts a means for using a reinforcing member 29 so that even if the apparatus is heated to a very high temperature, it does not cause permanent set in fatigue and cracks of the crucible 4 in the center.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a melting device,
In particular, the present invention relates to a miniaturizing melting device for granulating, agglomerating or fibrating, for the purpose of melting and reusing incinerated ash generated by incineration of industrial waste, household waste, etc. .

[0002]

2. Description of the Related Art In recent years, dioxin, heavy metals, injection needles, etc., contained in the incinerated ash waste after incineration of garbage discharged from homes, factories, hospitals, etc. are thrown into the environment and pollute the environment. It has become a big social problem, and a means for treating these wastes is required.

As a means for treating the above-mentioned incinerated ash waste, a method of melting and solidifying, reducing and detoxifying is disclosed. For example, Japanese Patent Application No. 2000-324734 discloses an ash melting apparatus shown in FIG. A lid provided with a burner unit 3 using petroleum gas such as propane gas, butane gas, or city gas and oxygen gas as fuel in a central portion of a furnace body 1 having an exhaust port 13 and an ash input port 5 In a furnace equipped with 2, a melting apparatus is disclosed, which has a replaceable single-layer crucible 4 in the innermost layer of the furnace main body 1, and the opening of the crucible 4 is directed to the lid 2 side. .

[0004] The patent body will be described in more detail with reference to FIG. 1. The furnace body 1 has a crucible 4, a fluid sand 11, a first heat-resistant layer 8, a second heat-resistant layer 9, a third heat-resistant layer from the innermost wall. 10, an iron skin 12, an ash charging port 5 is provided at one location near the center of the side surface of the furnace body 1, a crucible protruding rod 6 is provided on the right side surface, and a melt 14 is discharged at the lower left. A discharge port 13 for exhausting gas is provided, a temperature sensor 7 is provided on the upper left side, and a position for dropping the crucible 4 is set so that the melt 14 does not contact the wall surface 16 of the discharge port 13. There is.

The crucible 4 is a heat-resistant type carbon content of 30 to 55%, which is commercially available, for example, from Japan Crucible Co., Ltd.
Using SiC charcoal silicon crucible of SiC 30-50%,
The first heat-resistant layer 8 and the second heat-resistant layer 9 can be made of fire-resistant castables, crucibles, fire-resistant bricks, etc. after being molded into a predetermined size and fired. One with high heat resistance is used. Third heat-resistant layer 10
A board or heat-insulating castable is used.

Like the furnace body 1, the lid 2 is composed of a first heat-resistant layer 8, a second heat-resistant layer 9, a third heat-resistant layer 10 and a steel shell 12 from the inside, a burner 3 is provided in the central portion, and it is on the side surface. As shown in FIG. 1, it is configured so that it can be opened and closed easily with a hinge and can be opened and closed with a screw or the like, as shown in FIG.

In this patent, when the crucible 4 is used up for a long period of time and needs to be replaced, the melting furnace is cooled, and then the lid 2 is opened to nearly 180 degrees. When the protrusions 17 on the side surface are rotated to direct the lid 2 downward, the crucible protruding rod 6 is hydraulically driven, or the crucible 4 is pushed by manual screw rotation or the like, and the action of the fluidized sand 11 is also added. The crucible 4 can be taken out easily,
The replacement can be carried out very easily.

Further, the ash melting apparatus in the patent is capable of being pivotally fixed around the protrusion 17 of the furnace body 1, the inclination of the furnace body 1 can be freely set, and the melt 14 A cylindrical anti-sticking material 19 having the same composition as the crucible is provided on the surface in order to adjust the outflow rate and to prevent the melt from adhering to the wall surface 16 of the discharge port 13 and solidifying and clogging. Is described as desirable.

According to the method of the patent, a heat-resistant type graphite carbon silicon crucible having a carbon content of 30 to 55% and SiC of 30 to 50%, which is commercially available, for example, from Japan Crucible Co., Ltd., is further used as the crucible 4. However, if the crucible 4 is used continuously for a long time at a high temperature of about 1600 to 1700 ° C. which is necessary for melting the ash, the crucible 4 is consumed so much that the melting furnace is often operated for repair. Stop or operate without knowing the bottom of the melting furnace,
In extreme cases, the heat-resistant layer inside the furnace may be destroyed and unusable, or the ash melt may cool and solidify due to the decrease in the temperature near the discharge port 13, causing the melting furnace to become unusable. This may cause problems, and the heat efficiency is not very good due to lack of heat insulation of the furnace wall, resulting in high fuel consumption, and the method of pushing out from one side with the crucible protruding rod 6 to replace the crucible. However, there are problems in that it cannot be easily pushed out, and it takes time to cool the crucible when it is replaced.

Therefore, the durability is remarkably improved as compared with the conventional one, and the problem that the ash melt is cooled and solidified and clogged due to the low temperature around the discharge port 13 and the melting furnace cannot be used is improved. The main issues were to improve the heat insulation of the furnace wall to improve thermal efficiency and reduce fuel consumption, and to make it easier to replace the crucible and improve work efficiency.

As a result, it is necessary to use a crucible having a three-layer structure, which is much less worn than the conventional crucible, and the discharge port 1
In order to prevent the temperature drop around 3, the auxiliary burner is used, the four-layer furnace wall is adopted to improve the heat insulation and the durability, and the lids are provided on both the left and right sides to form the crucible. Measures such as lowering the cost for taking out and improving work efficiency by shortening the cooling time when replacing the crucible were adopted.

FIG. 2 shows an embodiment of the invention, but the main parts are composed of a furnace body 1, a lid 2, a burner part 3, a crucible 4, an ash charging port 5, a temperature sensor 7, and the like.

The furnace body 1 is preferably cylindrical in shape,
It may be in the shape of a polygonal column such as a square column, and the wall has a first heat-resistant layer 20 using castable from the innermost side, a first heat-insulating layer 21 such as asbestos, a second heat-resistant layer 22 such as castable, and asbestos. Second insulation layer 23, iron skin 12
The ash charging port 5 is provided on the upper surface of the furnace body 1, and the molten metal leak sensor 28 is provided in the backup sand 25 between the first crucible 24 and the second crucible 26. 24 is configured to detect an abnormality such as cracking, and there are two lids 2 on the right side and the left side, a discharge port 13 for discharging and discharging the melt 14 is provided on the lower left side, and an upper left side and a discharge side 13 are provided. A temperature sensor 7 is provided at the outlet 13, and a drop position 18 of the crucible 4 is provided so that the melt 14 does not contact the wall surface 16 of the discharge port 13.

The crucible 4 is, for example, the first crucible 2 from the inside.
4. The structure of at least three layers of the backup sand 25 and the second crucible 26, and the first crucible 24 is durable even at a high temperature of about 1700 to 2400 ° C. such as aluminum titanate type, alumina type, zirconia type, magnesia type, etc. The backup sand 25 uses a magnesia cement heat-resistant type, and the second crucible 26 has a carbon content of 30 to 30 made by Nippon Crucible Co. 55%, SiC 30-50%
Although a graphite charcoal siliceous crucible of a certain degree is used, at least by adopting this three-layer structure, the thermal conductivity of the conventional graphite charcoal siliceous crucible is extremely good, so that cracks due to thermal shock do not occur. Taking advantage of its advantages, the ultra-high temperature endurance type first crucible 24 is used as the contact point with the innermost layer of molten ash, and the heat resistant and highly durable backup sand 25 is used on the outside to make it extremely Good high-temperature long-term durability can be obtained, the number of times the crucible needs to be replaced, which has been frequently required in the past, can be significantly reduced, and if the crucible 4 has three or more layers, it is of course even better.

The lids 2 are provided at two places on the left and right, and like the furnace body 1, from the inside, a first heat-resistant layer 20 using castable, a first heat-insulating layer 21 such as asbestos, and a second heat-resistant using castable. Layer 22, a second insulating layer 23 such as asbestos,
It consists of five layers of iron skin 12, a burner 3 on the left lid 2.
Is provided slightly downward toward the opening of the crucible 4, and the flame of the auxiliary burner 27 is provided below the outlet 13 for the purpose of preventing solidification of molten ash due to cooling in the vicinity of the outlet 13. Aim at the vicinity of, and the left and right lids 2,
The hinges on the side surfaces allow easy opening and closing, and they are fixed to the furnace body 1 in an airtight manner so that they can be opened and closed with screws or the like, as shown in FIG.

In order to operate the melting furnace shown in FIG. 2, for example, in the state shown in FIG. 2, for example, a mixed gas of propane gas and oxygen gas in an equivalent amount is blown from the burner 3 and ignited at the same time.
The temperature inside the furnace is 1600 to 1650 ° C due to the temperature sensor 7.
When the incineration ash is put in through the ash input port 5 after confirming that the ash is in the controlled state, the ash is less scattered due to the slower blowing speed of the flame, and the high temperature is easily obtained, so the ash is promptly discharged. The ash is melted, and the melted substance 14 becomes a liquid and drops into the water 15 from the discharge port 13 and is granulated. It can be made into lumps or can be made into fibers by stretching, and can be effectively used as aggregates or reinforcing materials for concrete and asphalt.

[0017]

According to the method described above with reference to FIGS. 1 and 2, since it is heated to an extremely high temperature of 1600 to 1650 ° C. or higher, the center crucible is settled or self-weighted. However, there have been some problems, such as the occurrence of many cracks due to the stress strain in the vertical direction due to, which has been a problem.

[0018]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention is reinforced so that even if it is heated to an extremely high temperature of 1600 to 1650 ° C. or higher, the crucible in the center does not get settled or cracked. The means of using the member is adopted.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is a side sectional view of an embodiment of the present invention, in which the melt 1 is formed near the mouth of the crucible 4.
4 is a configuration including a reinforcing member 29 having four outlets 30. More specifically, FIG. 4 shows a structure in which the reinforcing member 29 is inserted in the crucible 4 having a three-layer structure and is viewed from the mouth side of the crucible 4. It is an example of a side view when the reinforcing member 29 has an outlet 30 that opens downward.
With the configuration including 9, it is possible to prevent the phenomenon that the central crucible is settled by being heated to an extremely high temperature and that many cracks are caused by vertical stress strain due to its own weight. By providing the reinforcing member 29 on the mouth side of the crucible 4,
It was found that the heat from the burner section 3 is less likely to escape from the inside of the crucible 4 and the heat stays, so that the thermal efficiency is improved and the fuel efficiency is significantly improved.

The present invention is not limited to the apparatus for melting ash of industrial waste, and can be applied to any melting furnace using a crucible.

[0021]

According to the present invention, in a melting furnace using a crucible, by adopting a structure in which a reinforcing member 29 having an outlet 30 is provided near the mouth of the crucible 4, the crucible that has been a problem in the past is subject to settling. Deformation due to
The phenomenon that many cracks are generated due to stress strain in the vertical direction due to its own weight is eliminated, and by providing the reinforcing member 29 on the mouth side of the crucible 4, it becomes difficult for heat from the burner portion 3 to escape from the inside of the crucible 4, Since heat easily accumulates, the thermal efficiency is improved, and the fuel consumption is significantly improved, which is an unexpected effect.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of a conventional method.

FIG. 2 is a side sectional view showing another embodiment of the conventional method.

FIG. 3 shows a reinforcing member 2 near the mouth of the crucible 4 according to the present invention.
FIG. 9 is a side sectional view showing an example when 9 is provided.

FIG. 4 is a side view showing an example of the vicinity of the reinforcing member 29 when viewed from the mouth side of the crucible 4 according to the present invention.

[Explanation of symbols]

1 furnace body 2 lid 3
Burner section 4 Crucible 5 Ash input port 6
Crucible protruding rod 7 Temperature sensor 8 First heat-resistant layer 9
Second heat-resistant layer 10 Third heat-resistant layer 11 Fluid sand 1
2 Iron crust 13 Discharge port 14 Melt 1
5 Water 16 Wall 17 Protrusion 1
8 Drop position 19 Sticking prevention material 20 First heat-resistant layer 2
1 1st heat insulation layer 22 2nd heat resistance layer 23 2nd heat insulation layer 2
4 First crucible 25 Backup sand 26 Second crucible 2
7 Auxiliary burner 28 Hot water leak sensor 29 Reinforcement member 3
0 Outlet

Claims (4)

[Claims] 1. A melting apparatus using a crucible, wherein a reinforcing member 29 having an outlet 30 is provided near the opening of the crucible 4. 2. The ash according to claim 1, characterized in that a rectangular cutout portion is provided below the standing disk-shaped reinforcing member 29, and the cutout portion forms the outflow port 30. Melting device. 3. A furnace comprising a furnace body 1 having a discharge port 13 and an ash charging port 5 and a lid 2 provided with a burner 3,
The innermost layer of the furnace body has a replaceable crucible 4, the opening of the crucible 4 is directed toward the lid side having the burner, and the ash is melted, and the melt 14 is discharged from the discharge port 13 by the action of gravity. The ash melting apparatus according to claim 1, wherein 4. The ash melting apparatus according to claim 1, wherein the lids 2 are provided at two places on both the left and right sides.