JPH07260357A - Ash-melting furnace apparatus - Google Patents

Abstract

PURPOSE:To realize the compactification of a furnace, suppress the generation of NOx and homogenize a melt by providing a burner in an opening of a side wall of a furnace body and an exhaust-discharge outlet in an opening of another side wall and arranging a melt chamber in a bottom wall from which the melt overflows to the exhaust-discharge outlet. CONSTITUTION:A furnace body 1 is provided with a burner 2 in an opening of a side wall 3 and an exhaust-discharge outlet 5 in an opening in another side wall 4. The furnace body 1 is further provided in a bottom wall thereof with a melt chamber 6 from which the melt overflows to the exhaust-discharge outlet 5. Ash preliminarily mixed with air or oxygen is fed together with fuel and is made to burn by the burner 2 while being circulated in a slewing device 7. Combustion gas is made to diffuse in an opening 9 and flat flame 11 is formed and circulation flow is simultaneously formed in the interior 10 of the furnace. Part of particles of the ash are made to move along an incline ceiling wall 8 before being allowed to fall into the melt chamber 6. Thus, the atmosphere within the furnace 10 is stirred and the melting of the ash and the homogenization of the melt are facilitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ash melting furnace apparatus.

[0002]

2. Description of the Related Art Ingredients such as incinerated ash contain volatile components, which are foamed at a high temperature and must be degassed. Conventionally, it is a method of sequentially melting from the surface of the incineration ash by a burner, and there are various devices such as an inclined reverberation furnace, a swirling melting furnace, an electric melting furnace, etc. for performing this method.

[0003]

DISCLOSURE OF THE INVENTION In the above-mentioned furnace, dust is often scattered to the outside due to exhaust gas or the like. In addition, since the melting depends only on the radiative heat transfer, the facility has to be increased in size due to the necessity of the area of the ash surface and the like. Further, in the electric melting furnace, although the scattering of dust can be suppressed, the melting energy cost is very high, and the electrodes and the like are consumed so much that there is a big problem in terms of operating cost.

[0004]

In order to solve the above-mentioned problems, according to the present invention, a burner is opened in a side wall of a furnace body, and an exhaust / exhaust port is formed in a lower part of the side wall of the furnace body opposite to the burner.
The ash melting apparatus is provided with a molten metal chamber at the bottom of the furnace, the molten metal overflowing into the exhaust / exhaust port.

Further, according to the present invention, the burner swirls combustion air or a premixed air of oxygen and ash to hold a swirler for forming a flat flame. A furnace melting apparatus is provided.

Further, the present invention provides the ash melting apparatus according to claim 1, characterized in that the ceiling of the furnace body is constituted by an inclined ceiling wall slightly lowered from the burner toward the exhaust / exhaust port. is there.

[0007]

The ash premixed with air or oxygen is supplied to the burner and ejected through the swirler. At the same time, when the fuel gas is supplied to the burner, the premixed gas and the fuel gas swirl to the burner. Combustion starts there. Then, the combustion gas forms a plane flame while rapidly expanding at the opening and forms a circulating flow in the furnace as indicated by an arrow in the figure. At the same time, the ash particles that have started to dissolve in the flame move on the side wall around the opening, and part of the ash particles flow from the lower side of the side wall to the molten metal chamber, while the other part moves to the inclined ceiling wall. While moving, it drops as a drop into the molten metal chamber. Since the ceiling wall is inclined as described above, a part of the molten metal is melted and homogenized while moving along the wall surface while undergoing radiative heat transfer and convective heat transfer and falls into the melting chamber. After being completely melted and homogenized in the molten metal chamber, the molten metal overflows and is discharged from the exhaust / discharge port. At this time, as described above, a circulating flow is formed in the furnace as shown by the arrow in the figure, whereby the atmosphere in the furnace is agitated to promote melting and homogenization of ash.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference numeral 1 is a furnace body, and 2 is a side wall 3 of the furnace body 1.
It is a burner opened at the opening 9. An exhaust / exhaust port 5 is formed in the lower portion of the side wall 4 opposite to the burner 2,
At the bottom of the furnace, a molten metal chamber 6 is formed in which the molten metal overflows into the exhaust / exhaust port 5. The burner 2 holds a swirler 7 that swirls combustion air or a premixed air of oxygen and ash. Further, the ceiling of the furnace body 1 is constituted by an inclined ceiling wall 8 slightly lowered from the burner 2 to the exhaust / exhaust port 5. The angle of the ceiling wall 8, that is, θ in the figure, may be in the range of 10 to 45 degrees in consideration of the flow state of the molten metal.

The ash premixed with air or oxygen is supplied to the burner 2 from the air supply unit 12 and ejected through the swirler 7, and at the same time when the fuel gas is supplied to the burner 2, the premixed air and the ash are mixed. The fuel gas starts combustion in the burner 2 while swirling. Then, the combustion gas forms a flat flame 11 while rapidly expanding at the opening 9, and forms a circulating flow in the furnace 10 as shown by an arrow in the figure. At the same time, the ash particles that have started to dissolve in the flame move on the side wall 3 around the opening 9 and partly flows from the lower side of the side wall 3 to the molten metal chamber 6, while the other part is While moving to the sloping ceiling wall 8, it drops from the side wall 4 into the molten metal chamber 6 as a drop. Since the ceiling wall 8 is inclined as described above, a part of the molten metal is melted and homogenized while moving along the wall surface while undergoing radiative heat transfer and convective heat transfer and falls into the melting chamber 6. . After being completely melted and homogenized in the molten metal chamber 6, the molten metal 13 overflows and is discharged from the exhaust / exhaust port 5 below the side wall 4 on the opposite side.
At this time, as described above, the circulation flow as shown by the arrow in the drawing is formed in the furnace 10, so that the inside 10
The atmosphere is stirred to promote ash melting and homogenization.
At this time, the air ratio of the burner 2 is 1.0 to 1.5, and the temperature of the furnace 10 is 1200 to 1600 ° C. Further, in actual operation, the flow of ash and gas is not fixed by intentionally and periodically changing the burner input or the air ratio, or the amount of ash, for example, from several seconds to several tens of seconds. .

[0010]

As described above, the present invention has the following effects. The furnace body can be made extremely compact by using a unique structure of the furnace body and a burner that forms a swirling plane flame. Because ash is melted in the flame, energy saving by improvement at the same time the heat transfer effect the NO _X generated flame is cooled is suppressed it can be achieved. On the ceiling wall surface and each side wall surface, friction and collision between the agitated combustion gas and ash are repeated, so that melting is promoted synergistically with radiant heating and homogenization of the molten metal can be achieved. Especially on the side wall, the ash directed downward is absorbed by the contact with the molten metal in the molten metal chamber, and the melting is completed quickly. This has a great effect that it is possible to prevent dust from being scattered by mixing with the atmospheric gas. Further, the circulating flow of the combustion gas in the furnace acts to keep the molten metal in the molten metal chamber at a high temperature, and prevents the solid content from remaining and flowing out from the discharge port.

[0011]

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view of the present invention.

[Explanation of symbols]

 1 Furnace Body 2 Burner 3 Side Wall on Burner Side 4 Side Wall on Opposite Side 5 Exhaust and Discharge Port 6 Melt Chamber 7 Swirler 8 Inclined Ceiling Wall 9 Opening 10 Inside Furnace 11 Plane Flame 12 Air Supply Section 13 Molten Metal

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Claims (3)

[Claims] 1. A burner is opened in the side wall of the furnace body, and an exhaust / exhaust port is formed in the lower part of the side wall of the furnace body on the side opposite to the burner.
An ash-melting furnace apparatus characterized in that a molten metal chamber is provided at the bottom of the furnace so that the molten metal overflows to the exhaust / exhaust port. 2. The ash melting furnace apparatus according to claim 1, wherein the burner has a swirler that swirls combustion air or a premixed air of oxygen and ash to form a flat flame. 3. The ash melting furnace apparatus according to claim 1, wherein the roof of the furnace body is constructed as an inclined ceiling wall which is slightly lowered from the burner toward the exhaust / exhaust port.