JPH07103439A - Combustion air supply device in carbonized gasification incinerator - Google Patents

Abstract

PURPOSE:To provide a device which is capable of eliminating a smoldering phenomenon mainly in the latter half of combustion time and inhibiting the generation of surplus gas to attain perfect combustion and preventing the genera tion of dioxin contained in an exhaust gas as much as possible in a dry gasifica tion incinerator. CONSTITUTION:A fluid injection nozzle 5 having an injection hole which is opened to a bottom unit 7 of a combustion chamber, is installed to a furnace wall 1 of an incinerator separately from an air supply hole 4. The fluid injection nozzle 5 is designed to inject an air at a slant directed at substantially the central point 7a of the bottom with a pressure which reaches the above bottom in such an extent that prevents incinerated ashes from whirling in the combustion chamber. In this case, it is also advisable that one more fluid injection nozzle be installed side by side so as to inject combustion air on a slant at the cornered part of the bottom 7 of the combustion chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion air supply device which contributes to complete combustion of a material to be burned in a furnace.

[0002]

2. Description of the Related Art Pyrolysis gasification incinerators ignite the upper part (surface layer) of the incinerator put into a combustion chamber without a grate and are forced into the furnace chamber from a plurality of air intakes provided on the wall of the combustion chamber. Combustion is promoted by the supplied combustion air, and the middle and lower incinerators are dried and gasified along with the combustion of the upper incinerator, and this carbonization gas is combined with the combustion air in the upper part of the furnace chamber. It is designed to burn.

In such a dry distillation gasification incinerator, it is necessary to supply an appropriate amount of combustion air all over the combustion chamber. For example, JP-A-2-282608 and JP-A 3-1.
The invention described in Japanese Patent No. 94308 adopts a structure in which pipes are embedded in multiple stages on the peripheral wall of the combustion chamber, air is supplied to the pipe from the outside, and air is jetted toward the combustion chamber from a large number of injection ports on the pipe surface. .

[0004]

However, in the above-described supply device, when a large amount of air is vigorously introduced into the combustion chamber, the temperature of the furnace rises sharply depending on the type of incinerated matter, so that the air of relatively low pressure is supplied. , For example, 0.2 to 0.4 at maximum
It is designed to blow air of about Kg / cm3. For this reason, in a large incinerator, air is not always sufficiently supplied to the center and bottom of the combustion chamber, and especially in the latter half of combustion, the incinerator remaining in the center of the combustion chamber smolders and produces a large amount of gas. May be generated. Also, a similar phenomenon is observed in the bottom corner of the combustion chamber in some cases. Although some of these gases are burned as described above, most of them are discharged as exhaust gas containing unburned substances to the outside of the furnace.

It is well known that unburned substances remaining in exhaust gas due to incomplete combustion generate dioxin. In the dry distillation gasification incinerator, middle and lower combustion products are gasified and combusted, so that unless a large amount of generated gas is efficiently combusted, dioxins are easily generated.

The object of the present invention is to eliminate the smoldering phenomenon mainly in the latter half of the combustion period in a dry distillation gasification incinerator, to achieve complete combustion to suppress the generation of extra gas, and to prevent the generation of dioxins in exhaust gas as much as possible. The present invention is to provide a combustion air supply device.

[0007]

In order to achieve the above-mentioned object, the present invention provides a dry distillation gasification incinerator with a fluid injection nozzle having an injection port opening toward the bottom of the combustion chamber on the wall surface of the incinerator. It is arranged separately from the air supply port for combustion, and the air is jetted obliquely toward the bottom with a pressure that reaches the above bottom so that the incineration ash in the combustion chamber does not rise from this fluid injection nozzle. It is characterized by

The fluid injection nozzle injects air obliquely toward the substantially central portion of the bottom of the combustion chamber at the above pressure. Further, this fluid injection nozzle may be used as a first fluid injection nozzle, and this may be combined with a second fluid injection nozzle that injects air obliquely toward the corner of the bottom of the combustion chamber. The second fluid injection nozzle is attached to approximately the center of the upper part of the furnace wall,
The injection port may be branched into a plurality of parts, or may be rotated around the vertical axis.

The air jetted into the combustion chamber from the jet outlet of the nozzle is jetted at a pressure of, for example, 1.5 to 4.0 kg / cm3, although it varies depending on the size of the combustion chamber.

[0010]

In the present invention, for example, when the combustion in the combustion chamber is approaching the final stage, air is jetted obliquely from the fluid injection nozzle toward the incinerated material in the center of the bottom of the combustion chamber. This air directly supplies the oxygen for combustion to the incineration material at a position where the air supplied from the combustion air supply port is hard to reach, and flows so as to expose the bottom of the combustion chamber and stays in the bottom of the combustion chamber. Stir the combustion gas. As a result, the unburned gas in the combustion chamber is completely burned as much as possible.

Further, the air jetted obliquely toward the bottom corner of the combustion chamber acts on the combustion product in this corner in the same manner, and the above combustion product which is difficult to burn only with the air from the air supply port is discharged. To burn. At the same time, when the air from this injection nozzle is blown in the above direction from the central portion of the upper part of the furnace wall, it increases the residence time of the combustion gas and unburned gas above the combustion chamber and disturbs the combustion chamber. To bring the gas into a more violent turbulent state and complete combustion of the gas.

[0012]

The present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 is a conceptual configuration diagram of a carbonization gasification incinerator equipped with an air supply device according to an embodiment of the present invention.

In the figure, reference numeral 1 is a furnace wall, and 2 is a primary combustion chamber surrounded by the furnace wall 1. The combustion chamber 2 is 0.5 to
It has an internal volume of 3.0 m3. Reference numeral 3 denotes an air supply pipe embedded in the peripheral wall of the combustion chamber 2 and arranged in multiple stages in the vertical direction of the peripheral wall. A large number of air supply ports 4 opening toward the combustion chamber are formed in these pipes 3, and primary combustion air is ejected into the combustion chamber at a relatively low pressure, for example, 0.1 kg / cm3, through a blower or the like not shown. To be done.

Reference numeral 5 is an air injection nozzle mounted on the furnace wall 1 above the combustion chamber, and its injection port 6 (for example, 8 mm diameter) is open toward the center 7a of the bottom portion 7 of the combustion chamber 2.
From this injection port 6, air is directed toward the bottom 2a of the combustion chamber at a pressure that reaches the above-mentioned bottom 7 to the extent that the incineration ash in the combustion chamber is not raised, for example, in the present embodiment, a pressure of 1.5 to 2.0 kg / cm3. And is jetted diagonally.

The jetted air flows so as to wipe out the vicinity of the central portion 7a of the bottom of the combustion chamber as shown by the arrow in FIG. 1, and oxygen is contained in the incineration material exhibiting the smoldering phenomenon in the central portion of the combustion chamber in the latter stage of combustion. And ignite it. At the same time, this air gently raises the unburned gas remaining in the combustion chamber bottom portion 7 by the above flow and collides it with the flow of the air supplied from the air supply port 4 or the rising airflow associated with the combustion. The unburned gas in the combustion chamber is agitated. By suppressing the smoldering phenomenon and stirring the gas, the incinerated matter is completely burned in the combustion chamber.

The above air injection nozzle 5 is provided at an appropriate position on the furnace wall 1 of the combustion chamber 2. The furnace wall 1 is provided with a combustion material inlet 1a and an openable / closable lid 1b for closing the same, and the lid 1b also constitutes a part of the furnace wall 1. Therefore, the air injection nozzle 5 may be provided in the lid 1b.

FIG. 2 is a conceptual block diagram of a dry distillation gasification incinerator equipped with an apparatus according to another embodiment of the present invention. In this embodiment, the air injection nozzle used in the embodiment of FIG. 1 is the first injection nozzle 15, and the second injection nozzle 18
Is added. The second injection nozzle 18 basically has the same structure as the first injection nozzle 15, but the injection port 16 is not the bottom center 7a of the combustion chamber 12,
The bottom 7 is opened toward the corner 7b. Further, the injection nozzle 18 is attached to substantially the center of the upper part of the furnace wall.

Therefore, the air jetted from the jet nozzle 18 is jetted from the upper center of the combustion chamber 2 toward the bottom corner portion 7b as shown by the arrow in FIG. 2, and the incineration material at the corner portion 7b. Supply the oxygen needed for combustion. Further, the flow suppresses the ascending force of the gas to the upper part of the combustion chamber, prolongs the residence time of the gas in the combustion chamber, and partially disturbs the gas.

The first jet nozzle and the second jet nozzle are
Mainly in the latter stage of combustion, air is jetted in a predetermined direction at the same time or by shifting the time as necessary. Also, as can be seen in FIG.
May have a plurality of branched injection ports 26, and each of the injection ports 26 may open toward different corners of the bottom of the combustion chamber.

Further, the second injection nozzle may be constructed so as to rotate around the vertical axis with the injection port facing the bottom of the combustion chamber. When it is rotatable in this way, the air blown from the injection port diffuses to the peripheral edge of the bottom of the combustion chamber,
Air for combustion is supplied to the entire edge. In addition, retention and disturbance of the unburned gas rising in the combustion chamber are further caused.

As described above, according to the present invention, a fluid injection nozzle having an injection port opening toward the bottom of the combustion chamber is provided on the wall surface of the incinerator, and air is supplied from the fluid injection nozzle at a predetermined pressure. Since the fuel is jetted obliquely toward the bottom, oxygen for combustion can be supplied to a place where the air supplied from the combustion air supply port is hard to reach, and in particular, the smoldering phenomenon of the incineration product in the latter stage of combustion can be eliminated. Further, the air jetted obliquely downward toward substantially the center of the bottom of the combustion chamber flows so as to expose the bottom, stirring the gas staying in the center of the bottom to contribute to complete combustion of the gas. Furthermore, when an injection nozzle that ejects air that obliquely flows toward the corner of the bottom of the combustion chamber is provided, the residence time of the gas in the combustion chamber is increased, which can contribute to further complete combustion. The present invention thus suppresses the generation of unburned gas in the dry distillation gasification incinerator and completely burns the generated unburned gas, so that the generation of dioxin can be suppressed as much as possible.

[Brief description of drawings]

FIG. 1 is a conceptual configuration diagram of a combustion furnace equipped with an apparatus according to an embodiment of the present invention.

FIG. 2 is a conceptual configuration diagram of an incinerator equipped with an apparatus according to another embodiment of the present invention.

FIG. 3 is an explanatory view showing another example of the second air injection nozzle used in the present invention.

[Explanation of symbols in the figure]

 1 ・ ・ ・ ・ Furnace wall 2 ・ ・ ・ ・ ・ ・ Combustion chamber 3 ・ ・ ・ ・ ・ ・ Pipe 4 ・ ・ ・ ・ ・ ・ Air supply port 5 ・ ・ ・ ・ ・ ・ Air injection Nozzle 6,16 ・ ・ ・ ・ Injection port 6a ・ ・ ・ ・ ・ ・ Base end 7 ・ ・ ・ ・ Combustion chamber bottom 7a ・ ・ ・ ・ ・ ・ Bottom center 7b ・ ・ ・ ・ ・ ・ Bottom corner Part 15: First injection nozzle 18: Second injection nozzle

Claims (6)

[Claims] 1. An incinerator charged into a combustion chamber without a grate is combusted from an upper part thereof, and dry distillation gas generated from a dried middle and lower part is supplied together with air supplied from a combustion air supply port. In a dry distillation gasification incinerator to be burned, a fluid injection nozzle having an injection port that opens toward the bottom of the combustion chamber is installed on the furnace wall of the incinerator separately from the air supply port. A device for supplying combustion air in a carbonization gasification incinerator, characterized in that air is jetted obliquely toward the bottom with a pressure reaching the bottom so that the incineration ash in the combustion chamber does not rise. 2. The fluid injection nozzle is attached to an edge portion of an upper portion of a furnace wall and injects air obliquely toward a substantially central portion of a bottom portion of a combustion chamber. For supplying combustion air in a dry distillation gasification incinerator in Japan. 3. A first fluid injection nozzle for injecting air obliquely toward a substantially central portion of a bottom portion of the combustion chamber, and a fluid injection nozzle for obliquely injecting air toward a corner portion of the bottom portion of the combustion chamber. It has a 2nd fluid injection nozzle, The supply device of the combustion air in the carbonization gasification incinerator of Claim 1 characterized by the above-mentioned. 4. The second fluid injection nozzle is disposed substantially at the center of the upper part of the furnace wall and has a plurality of branched injection ports, each injection port opening toward a different corner of the combustion chamber. The supply device for combustion air in a dry distillation gasification incinerator according to claim 3, wherein 5. The apparatus for supplying combustion air in a carbonization gasification incinerator according to claim 3, wherein the second fluid injection nozzle rotates about a vertical axis as a central axis. 6. From 1.5 to 4.0 k from the injection port of the nozzle
Air is jetted at a pressure of g / cm3. The apparatus for supplying combustion air in a carbonization gasification incinerator according to any one of claims 1 to 5, wherein: