JPH06201118A - Waste incinerator - Google Patents

Abstract

PURPOSE:To prevent the adhesion of ash onto the hopper unit of a secondary combustion chamber and the accumulation of ash in the bent unit of upper end of a choked flow passage. CONSTITUTION:Part of fluidized medium, taken out of a lower fluidized medium outlet port 7 of a primary combustion chamber 1 and constituting a fluidized bed 5, is sent into a secondary combustion chamber 12 from a fluidized medium inlet port 28 through a fluidized medium circulating passage 29 and is fused by the combustion heat of combustible gas in the secondary combustion chamber 12, then, scrapes down ash, adhered onto a hopper unit 14 or a bent unit 35 at the upper end of a choked flow passage 18 and, thereafter, is returned into the primary combustion chamber 1 through a fluidized medium outlet port 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste incinerator for incinerating waste such as municipal waste.

[0002]

2. Description of the Related Art Generally, a waste incinerator puts waste into a combustion chamber and burns it.
The waste is burned through the steps of thermal decomposition of the waste and combustion of combustible gas generated by the thermal decomposition.

However, in the conventional waste incinerator, the thermal decomposition of the waste and the combustion of the combustible gas are carried out in the same combustion chamber, so that both the thermal decomposition of the waste and the combustion of the combustible gas are sufficient. Not performed, for example, combustible gas, because the residence time in the combustion chamber is not sufficient, mixing with air is insufficient, incomplete combustion may occur, harmful substances may be generated and discharged as they are. there were.

Therefore, in recent years, it has been proposed to perform thermal decomposition of waste and combustion of combustible gas in independent combustion chambers.

2 and 3 show a currently proposed waste incinerator having an independent combustion chamber.
1 is a waste supply port 2 formed in the upper part and a hopper part 3 in the lower part
Formed in the primary combustion chamber, 4 is an air diffuser provided so as to partition an intermediate portion of the primary combustion chamber 1, 5 is a fluidized bed formed by depositing a fluidizing medium on the air diffuser 4, and 6 is primary combustion A burner mounted toward the fluidized bed 5 in the middle portion of the chamber 1, 7 is a fluid medium outlet provided at the lower end of the hopper portion 3, 8 is a fluid medium inlet formed in the middle portion of the primary combustion chamber 1, and 9 is The fluid medium circulation path connecting between the fluid medium outlet 7 and the fluid medium inlet 8 is a fluid medium conveyor provided in the middle of the fluid medium circulation path 9, and 11 is the fluid medium conveyor 10 output of the fluid medium circulation path 9. It is a sieving device provided on the side.

A secondary combustion chamber 12 is disposed above the primary combustion chamber 1, has a combustion gas discharge port 13 at its upper end, and has a hopper portion 14 at its lower end, and 15 is a secondary combustion chamber. A burner 16 provided in the middle of the combustion chamber 12 is a hopper 1
4 the ash outlet 17 formed at the lower end to the fluid medium circulation passage 9
It is an ash discharge path that is connected in the middle of.

Further, 18 is a squeezing passage raised from the upper part of the primary combustion chamber 1, 19 is formed at the upper end of the scavenging passage 18, and is connected to a side portion of the secondary combustion chamber 12 in a tangential direction. It is a horizontal bend.

Reference numeral 20 is an air supply passage connected to an external fan 21, 22 is a primary air supply passage branched from the air supply passage 20 to supply air to the diffuser pipe 4, and 23 and 24 are from the air supply passage 20. Secondary air supply passages 25, 2 which are branched to supply air to several positions of the squeezing passage 18.
Reference numerals 6 and 27 are valves provided in the middle of the primary air supply passage 22 and the secondary air supply passages 23 and 24, respectively.

Then, the air blower 21 is operated to supply air to the diffuser pipe 4 of the primary combustion chamber 1 through the air supply passage 20 and the primary air supply passage 22, thereby causing the fluidized bed 5 to flow and The fluidized bed 5 in the primary combustion chamber 1 is preheated by the burner 6, and in this state, the waste is introduced into the primary combustion chamber 1 from the waste supply port 2.

Then, the waste material introduced into the primary combustion chamber 1 is thermally decomposed in the preheated fluidized bed 5 to generate combustible gas, char (carbon) content and the like.

The char portion is burned by the air supplied from the air diffuser 4 to the primary combustion chamber 1, and the thermal decomposition of the char promotes the thermal decomposition of the waste.

The combustible gas generated by the thermal decomposition of the waste is squeezed passage 18 and the bent portion 19 at the upper end of the squeezed passage 18.
Since it is sent to the secondary combustion chamber 12 through the through, the waste is thermally decomposed at a constant rate in the primary combustion chamber 1 without being affected by the combustion of the combustible gas.

On the other hand, the combustible gas which is sent to the secondary combustion chamber 12 through the squeezing passage 18 and the bent portion 19 at the upper end of the squeezing passage 18 is, in the middle of the squeezing passage 18, the secondary air supply passage 2
After the air from 3, 24 is mixed, it is introduced into the secondary air supply passages 23, 24 from the tangential direction.

Then, in the secondary air supply passages 23 and 24, a swirling flow is generated by the combustible gas mixed with air, the swirling flow promotes the mixing of the combustible gas and the air, and the secondary combustion is performed. Since the residence time of the combustible gas is sufficiently secured inside the chamber 12, the combustible gas is completely burned by the ignition by the burner 15, and the generation of harmful substances due to incomplete combustion is prevented.

Then, the combustion gas generated by combustion is discharged from the combustion gas discharge port 13 at the upper end of the secondary combustion chamber 12.

Separately from the above, in the primary combustion chamber 1, a part of the fluidized medium constituting the fluidized bed 5 is passed from the fluidized medium outlet 7 at the lower end of the hopper 3 to the sieve device 11 via the fluidized medium conveyor 10. After the incombustibles are removed by the sieving device 11, the fluid is circulated from the fluidized medium inlet 8 to the primary combustion chamber 1 via the fluidized medium circulation passage 9.

Furthermore, the squeezing passage 18 is entrained in the combustible gas.
The ash that has risen above is centrifugally separated in the secondary combustion chamber 12, is extracted from the ash outlet 17 at the lower end of the hopper portion 14 of the secondary combustion chamber 12 to the ash discharge passage 16, and is subjected to the primary combustion via the fluid medium circulation passage 9. Sent to Chamber 1.

[0018]

However, the above-mentioned conventional waste incinerator has the following problems.

That is, the squeezing passage 18 is entrained in the combustible gas.
The ash that has risen above is melted by the combustion heat of the combustible gas inside the secondary combustion chamber 12 and adheres to the hopper portion 14 of the secondary combustion chamber 12.

Further, the ash content entrained in the combustible gas is accumulated on the bent portion 19 at the upper end of the squeezing passage 18.

In view of the above situation, the present invention provides a waste incinerator capable of preventing ash adhesion in the hopper portion of the secondary combustion chamber and ash accumulation in the bent portion at the upper end of the squeezing passage. That is the purpose.

[0022]

According to a first aspect of the present invention, a secondary combustion chamber is disposed above a fluidized bed type primary combustion chamber having a waste supply port, and the secondary combustion chamber is squeezed from an upper portion of the primary combustion chamber. The flow passage is erected, and a bent portion connected to the side of the secondary combustion chamber in the tangential direction of the secondary combustion chamber is formed at the upper end of the flow passage. The present invention relates to a waste incinerator characterized in that a fluidized medium circulation path is connected to a medium inlet and a fluidized medium outlet at a lower part of the secondary combustion chamber is connected to an upper part of the primary combustion chamber.

A second aspect of the present invention relates to the waste incinerator according to the first aspect, wherein the bent portion at the upper end of the squeezing passage is formed so as to have a downward slope with respect to the secondary combustion chamber.

[0024]

The operation of the present invention is as follows.

The thermal decomposition of the waste introduced from the waste supply port is performed inside the fluidized bed type primary combustion chamber, and the combustible gas generated by the thermal decomposition of the waste passes through the squeezing passage to the secondary side. It is guided to the combustion chamber and combustible gas is burned in the secondary combustion chamber.

Further, according to the invention of claim 1, in the primary combustion chamber, a part of the fluidized medium constituting the fluidized bed taken out from the fluidized fluid outlet at the lower part is flown through the fluidized medium circulation passage to the fluidized medium inlet. From the fluidized medium outlet to the secondary combustion chamber, and after scraping off the ash that is melted and adhered by the combustion heat of the combustible gas in the secondary combustion chamber, it is returned from the fluid medium outlet to the primary combustion chamber.

According to the second aspect of the present invention, since the bent portion at the upper end of the squeezing passage is formed so as to have a downward slope with respect to the secondary combustion chamber, accumulation of ash at the bent portion is prevented.

[0028]

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

FIG. 1 shows an embodiment of the present invention.

Further, in the figure, as in FIGS. 2 and 3, 1 is a primary combustion chamber, 2 is a waste supply port formed at the upper end of the primary combustion chamber 1, and 3 is formed at the lower end of the primary combustion chamber 1. Hopper part, 4
Is an air diffuser for partitioning the intermediate portion of the primary combustion chamber 1, 5 is an air diffuser 3
A fluidized bed formed on the upper side, 6 a burner disposed in the primary combustion chamber 1 toward the fluidized bed 5, 7 a fluidized medium outlet formed at the lower end of the hopper 3, and 10 a midway portion of the fluidized medium circulation path 9. A fluidized medium conveyor provided at 11, and a fluidized medium conveyor 1
It is a sieving device provided on the exit side of 0.

Further, 12 is a secondary combustion chamber arranged above the primary combustion chamber 1, 13 is a combustion gas discharge port formed at the upper end of the secondary combustion chamber 12, and 14 is a lower end of the secondary combustion chamber 12. A burner arranged in the secondary combustion chamber 12, and a squeezing passage raised from the upper portion of the primary combustion chamber 1.

Reference numeral 20 is an air supply passage for supplying air from an external fan 21, reference numeral 22 is a primary air supply passage for supplying air from the air supply passage 20 to the air diffusing pipe 3 of the primary combustion chamber 1, and 23. , 24 are secondary air supply paths for supplying the air from the air supply path 20 to any position of the squeezing path 18,
Reference numerals 25, 26, and 27 are valves provided in the middle of the primary air supply passage 22 and the secondary air supply passages 23 and 24.

In the present invention, the fluidized medium circulation passage 2 is further provided between the fluidized medium outlet 7 at the lower portion of the primary combustion chamber 1 and the fluidized medium inlet 28 formed in the hopper portion 14 of the secondary combustion chamber 12.
9 is connected, and a fluid medium outlet 30 formed in the lower portion of the secondary combustion chamber 12 is connected to a fluid medium inlet 32 in the upper portion of the primary combustion chamber 1 via an L-shaped valve 31 which is opened and closed by seal air.
Connect to.

Reference numeral 33 is a sealing air supply passage connecting the air supply passage 20 and the L-shaped valve 31, and 34 is a valve provided in the middle of the sealing air supply passage 33.

The bent portion 35 at the upper end of the squeezing passage 18 is formed so as to have a downward slope with respect to the secondary combustion chamber 12.

Next, the operation will be described.

The process of thermally decomposing the waste in the primary combustion chamber 1 and combusting the combustible gas generated by the thermal decomposition of the waste in the secondary combustion chamber 12 is the same as in FIGS. To do.

In the present invention, the bent portion 3 at the upper end of the squeezing passage 18 is used.
Since 5 is formed so as to have a downward slope with respect to the secondary combustion chamber 12, the ash content entrained in the combustible gas is prevented from accumulating on the bent portion 35 at the upper end of the squeezing passage 18.

Further, in the primary combustion chamber 1, a part of the fluidized medium constituting the fluidized bed 5 taken out from the fluidized medium outlet 7 at the lower end of the hopper section 3 is partially passed through the fluidized medium conveyer 10 and the sieving device 11 is provided.
To the secondary combustion chamber 12 from the fluidized medium inlet 28 via the fluidized medium circulation path 29, after the incombustibles have been removed by the sieving device 11, the combustible gas is burned in the secondary combustion chamber 12. The ash that is melted by heat and adhered to the hopper 14 is scraped off.

Then, the fluid medium in which the ash content adhering to the hopper portion 14 of the secondary combustion chamber 12 has been scraped off is sent from the air supply passage 20 to the L-shaped valve 31 via the sealing air supply passage 33, and the seal air is supplied and discharged. Is controlled by the valve 34 to be intermittently dropped into the primary combustion chamber 1 and circulated.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0042]

As described above, according to the invention of claim 1, it is possible to prevent ash from adhering to the hopper portion of the secondary combustion chamber, and according to the invention of claim 2, the upper end of the squeezing passage. An excellent effect that ash can be prevented from being accumulated in the bent portion of

[Brief description of drawings]

FIG. 1 is a schematic side view of an embodiment of the present invention.

FIG. 2 is a schematic side view of a conventional example.

FIG. 3 is a view taken along the line III-III in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Primary combustion chamber 2 Waste supply port 7 Fluid medium outlet 12 Secondary combustion chamber 18 Squeezing passageway 28 Fluid medium inlet 29 Fluid medium circulation passage 30 Fluid medium outlet 35 Bending part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mikio Mogi 2-1-1 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Ltd. Tokyo No. 1 factory (72) Inventor Kiyoshi Aoki Shinnaka, Isogo-ku, Yokohama, Kanagawa Prefecture Haramachi No. 1 Ishi Kawashima Harima Heavy Industries Ltd. Technical Research Institute

Claims (2)

[Claims] 1. A secondary combustion chamber is arranged above a fluidized bed type primary combustion chamber having a waste supply port, and a squeezing passage is raised from an upper part of the primary combustion chamber and the squeezing passage is provided. Form a bent portion connected to the side tangential direction of the secondary combustion chamber at the upper end of
A fluidized medium circulation path was connected between the fluidized medium outlet in the lower part of the primary combustion chamber and the fluidized medium inlet formed in the secondary combustion chamber, and the fluidized medium outlet in the lower part of the secondary combustion chamber was connected to the upper part of the primary combustion chamber. A waste incinerator characterized by this. 2. The waste incinerator according to claim 1, wherein the bent portion at the upper end of the squeezing passage is formed to have a downward slope with respect to the secondary combustion chamber.