JP2005241200A - Ash melting furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ash melting furnace capable of prolonging a service life greatly by suppressing local wear of a furnace wall due to flow of molten slag and having excellent economical property. <P>SOLUTION: This ash melting furnace 10 melts ashes X charged into a furnace body 12 through an ash charging port 15 to generate molten slag S and discharges it through a molten slag discharge port 18. A baffle plate 21 for changing flow of the molten slag S is provided in the furnace body 12 and can move in the furnace body 12. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ash melting furnace for melting and treating ash generated when incineration materials such as municipal waste and industrial waste are incinerated.

In recent years, ash melting by an ash melting furnace has become widespread from the viewpoint of decomposition of dioxins contained in incineration ash of waste. As this type of ash melting furnace, a DC electric resistance type is known (for example, see Patent Document 1).
This DC electric resistance type ash melting furnace has a furnace body into which ash is introduced from an ash inlet, a main electrode disposed in the furnace body, and a furnace bottom electrode provided at the furnace bottom. . In this ash melting furnace, the ash in the furnace body is sequentially melted by Joule heat by the current flowing between the main electrode and the furnace bottom electrode to form molten slag. Then, the molten slag in the furnace body is taken out from the molten slag discharge port on the side of the furnace body, and the molten exhaust gas generated in the furnace body is exhausted from the exhaust gas port in the upper part of the furnace body.
JP 2000-274649 A

By the way, since the furnace body which fuse | melts ash and makes a molten slag becomes high temperature, the refractory material is stuck on the furnace wall of the furnace body. This suppression of wear of the refractory material is an important problem related to the life of the ash melting furnace itself.
The wear of the refractory material is caused by the internal temperature of the furnace body, the components of the molten slag, and the flow of the molten slag, and is particularly greatly affected by the flow of the molten slag along the furnace wall. The influence of the flow of the molten slag increases as the flow rate of the molten slag increases, and the furnace wall may be locally worn out. Moreover, the flow of the molten slag in the furnace body is determined by the relative position between the ash inlet and the molten slag outlet. For this reason, when the flow of the molten slag is determined, the maximum flow velocity portion of the molten slag near the furnace wall is also determined, and the furnace wall near the maximum flow velocity portion is locally worn out.
And, in the ash melting furnace, when the part that is greatly worn down locally becomes less than the allowable remaining thickness, all the refractory materials on the furnace wall should be replaced even if the other part is healthy. There is a problem that the economy is bad.

  The present invention was made in view of the above circumstances, and provides an economical ash melting furnace capable of suppressing the local wear of the furnace wall due to the flow of molten slag and extending the service life. For the purpose.

The ash melting furnace according to the present invention employs the following means in order to solve the above problems.
The present invention relates to an ash melting furnace that melts the ash charged into the furnace body from the ash charging port into molten slag and discharges the molten slag from the molten slag discharge port. A board is provided.

As described above, since the baffle plate for changing the flow of the molten slag is provided in the furnace body, the position of the portion where the flow velocity of the molten slag is high is changed, and the portion where the flow velocity is high is located at a certain place on the furnace wall of the furnace body. You will never stay.
As a result, in this ash melting furnace, there is no problem that a part of the furnace wall of the furnace body is locally worn by the flow of the molten slag, and the life is extended and economically excellent.

Further, the baffle plate is movable in the furnace body, and the flow of the molten slag is changed by moving the position in the furnace body.
That is, by moving the baffle plate, the flow of the molten slag in the furnace body is constantly or periodically changed.

Further, the baffle plate is characterized in that it can be moved in each of a rotation direction around an axis line in the horizontal direction, the vertical direction, or the vertical direction.
Accordingly, the flow of the molten slag can be changed very easily by moving the baffle plate in all or any one of the rotational directions around the axis in the horizontal direction, the vertical direction, or the vertical direction.

The baffle plate may change the flow of the molten slag by changing its shape due to wear.
In this way, the flow of the molten slag is easily changed by the baffle plate being worn and the shape changing.

Further, the baffle plate is characterized in that the cross-sectional shape is rectangular.
In this manner, the flow of the molten slag is reliably and effectively changed by the baffle plate having a rectangular cross section.

Furthermore, it has a cooling mechanism inside the baffle plate.
Thus, by having a cooling mechanism, wear of a baffle plate is suppressed as much as possible, and the flow of the molten slag by the baffle plate is performed over a long period of time.

Further, the baffle plate is provided on the opposite side of the ash charging port with respect to the electrode disposed in the furnace body.
Thus, in particular, since the baffle plate is provided at a portion where the flow of the molten slag is fast on the opposite side of the ash charging port with respect to the electrode, the flow of the molten slag is effectively changed.

According to the ash melting furnace of the present invention, since the baffle plate for changing the flow of the molten slag is provided in the furnace body, the position of the portion where the flow rate of the molten slag is fast is changed, and the place where the flow velocity is high is It is possible to avoid staying at a certain place on the furnace wall.
As a result, in this ash melting furnace, it is possible to eliminate the problem that a part of the furnace wall of the furnace body is locally worn by the flow of the molten slag, and it is possible to achieve a long life and economically excellent. Can be.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic sectional view on the front side showing the structure of the ash melting furnace according to the present embodiment, FIG. 2 is a sectional view taken along the line PP in FIG. 1, and FIG. 3 is a plan view of FIG.
As shown in FIG. 1, the ash melting furnace 10 includes a cylindrical furnace body 12 having a furnace bottom 11 and a furnace lid 13 that covers an upper portion of the furnace body 12. The furnace body 12 has a main electrode 14 made of a graphite electrode in the furnace body 12, and the main electrode 14 is supported by the furnace lid 13 so as to be movable up and down.

An ash charging port 15 is formed in the furnace lid 13, and ash fed from the ash supply unit 16 is charged into the furnace body 12 from the ash charging port 15.
The furnace bottom 11 includes a furnace bottom electrode 17, and the ash X introduced into the furnace body 12 is caused by Joule heat by flowing a current between the main electrode 14 and the furnace bottom electrode 17 by the DC power source 20. The molten slag S is melted sequentially.

A molten slag discharge port 18 is formed in the side wall of the furnace body 12, and the molten slag S in the furnace body 12 is taken out from the molten slag discharge port 18.
Further, an exhaust gas port 19 to which an exhaust gas pipe is connected is provided at the upper part of the furnace body 12, and the molten exhaust gas generated in the furnace body 12 is exhausted from the exhaust gas port 19.

As shown in FIG. 2, in the ash melting furnace 10, a baffle plate 21 is suspended in a furnace body 12. The baffle plate 21 is a plate having a rectangular shape in sectional view, and a water-cooled cooling mechanism 23 composed of a piping path through which the refrigerant flows is built in the baffle plate 21.
The baffle plate 21 has an upper end supported by the drive mechanism 22 of the furnace lid 13 and a lower end extended into the furnace body 12 and disposed in the molten slag S.
As shown in FIG. 3, the drive mechanism 22 reciprocates the baffle plate 21 in its width direction, that is, in the left-right direction of the furnace body 12.

In the ash melting furnace 10 having the above-described configuration, when energization is performed between the main electrode 14 and the furnace bottom electrode 17, Joule heat is generated in the molten slag S and is charged into the furnace body 12 from the ash charging port 15. Melting of the ash X is started and molten slag S is generated. The melting gradually proceeds from the main electrode 14 side to the outside.
Here, based on the specific gravity difference, the molten slag S is separated into a salt layer having a relatively low specific gravity, a medium slag layer having a specific gravity, and a metal layer made of metals such as Fe, Cu, and Ni having a relatively high specific gravity. To do.
Then, the molten slag S in the furnace body 12 is taken out by appropriately opening the molten slag discharge port 18 on the side wall of the furnace body 12.

In the ash melting step, a flow along the furnace wall of the furnace body 12 is generated in the molten slag S in the furnace body 12. The flow of the molten slag S is determined by the relative position between the ash inlet 15 and the molten slag outlet 18.
Here, in the ash melting furnace 10 having the above-described structure, the baffle plate 21 is provided in the furnace body 12, and the baffle plate 21 can be reciprocated in the left-right direction by the drive mechanism 22. By moving 21, the direction of the flow of the molten slag S flowing in the furnace body 12 is changed.
Thereby, the position of the portion where the flow velocity of the molten slag S is fast is also changed, and the portion where the flow velocity is fast is not restricted to a certain place on the furnace wall of the furnace body 12.

As described above, according to the ash melting furnace 10 according to the above-described embodiment, the baffle plate 21 that changes the flow of the molten slag S is provided in the furnace body 12. It is possible to prevent the portion where the flow rate of S is fast from staying at a certain point on the furnace wall of the furnace body 12.
Thereby, in this ash melting furnace 10, the trouble that a part of the furnace wall of the furnace body 12 is locally worn out by the flow of the molten slag S can be eliminated, and the life can be extended. It can be made excellent.

In particular, the flow of the molten slag S in the furnace body 12 can be changed constantly or periodically by moving the baffle plate 21 by the drive mechanism 22.
In addition, the flow of the molten slag S can be reliably and effectively changed by the baffle plate 21 having a rectangular cross section, and further, the baffle plate 21 can be prevented from being worn as much as possible by having a cooling mechanism. The flow of the molten slag S can be changed over a long period of time.
Moreover, since the baffle plate 21 is provided at a location where the flow of the molten slag S is faster on the opposite side of the ash charging port 15 with respect to the main electrode 14, the flow of the molten slag S can be effectively changed. .

In the above-described embodiment, the baffle plate 21 is movable in the left-right direction. However, the movement direction of the baffle plate 21 is not limited to the left-right direction. The rotation direction may be about the direction axis.
That is, the flow of the molten slag S can be changed very easily by moving the baffle plate 21 in all directions or any one of the rotational directions around the axis in the horizontal direction, the vertical direction, or the vertical direction.

  Moreover, as the baffle plate 21, you may use what is worn out by the heat | fever and flow of the molten slag S, and a shape changes. In this case, the flow of the molten slag S can be easily changed by changing the shape of the baffle plate 21 due to wear.

  In the above embodiment, one baffle plate 21 is provided in the furnace body 12, but a plurality of baffle plates 21 may be provided in the furnace body 12, and by providing a plurality of baffle plates 21 in this way, In addition, the flow of the molten slag S in the furnace body 12 can be changed more effectively.

  In addition, this invention is not limited to the said embodiment, Of course, it can change variously in the range which does not deviate from the summary of this invention.

Schematic sectional view of the front side of the ash melting furnace Schematic sectional view of the side of the ash melting furnace Schematic plan view of ash melting furnace

Explanation of symbols

10 Ash melting furnace 12 Furnace body 14 Main electrode (electrode)
15 Ash inlet 18 Molten slag outlet 21 Baffle plate 23 Cooling mechanism S Molten slag X Ash

Claims (7)

An ash melting furnace that melts the ash charged into the furnace body from the ash charging port into molten slag and discharges it from the molten slag discharge port,
An ash melting furnace comprising a baffle plate for changing the flow of the molten slag in the furnace body.   The ash melting according to claim 1, wherein the baffle plate is movable in the furnace body, and the flow of the molten slag is changed by moving a position of the baffle plate in the furnace body. Furnace.   3. The ash melting furnace according to claim 2, wherein the baffle plate is movable in each of a rotation direction around an axis line in a horizontal direction, a vertical direction, or a vertical direction.   The ash melting furnace according to any one of claims 1 to 3, wherein the baffle plate changes the flow of the molten slag by changing its shape due to wear.   The ash melting furnace according to any one of claims 1 to 4, wherein the baffle plate has a rectangular cross-sectional shape.   The ash melting furnace according to any one of claims 1 to 5, wherein the baffle plate has a cooling mechanism therein. The ash melting furnace according to any one of claims 1 to 6, wherein the baffle plate is provided on an opposite side of the ash charging port with respect to an electrode disposed in the furnace body.

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