JP2947629B2 - Fluidized bed incinerator and its operation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluidized bed incinerator which can partially change the flow of sand in a sand layer, which is a fluidized bed, and a method of operating the same.

[0002]

2. Description of the Related Art As is well known, as an apparatus for efficiently and surely and completely burning incinerated materials such as municipal waste (hereinafter referred to as garbage) in a short period of time, a primary material is applied to a high-temperature sand layer as a fluidized bed. The fluidized bed refuse incineration that blows air to make the sand in this sand layer flow, breaks and gasifies the refuse using the flow of the sand and the excellent heat transfer characteristics of the sand, and burns the generated gas. Furnaces (hereinafter referred to as incinerators) are often used.

[0003] Hereinafter, the configuration of a typical incinerator will be described with reference to FIG. 7 of a sectional configuration explanatory view. Reference numeral 1 denotes a cylindrical furnace main body, and a fluidized bed is provided at the bottom of the furnace main body 1. A dispersing plate 3 that supports a certain sand layer 2 and has a configuration described below is provided.

[0004] The dispersing plate 3 is formed in a mortar-like shape made of a refractory material, communicates from the lower side to the upper side, and extends upward from the lower side.
A number of air distribution nozzles 4 having a secondary air inlet are provided, and a noncombustible material outlet 5 is provided at the bottom, that is, at the center in the radial direction.

The lower part of the dispersion plate 3 receives primary air supplied from a primary air blower (not shown) via a flow rate adjusting damper (not shown), and receives the primary air.
A wind box 10 for blowing the next air from the air dispersion nozzle 4 into the sand layer 2 is provided.

On the other hand, an incombustible substance extraction pipe 6 extends downward from the incombustible substance extraction port 5 through the wind box 10, and an incombustible substance extraction pipe is provided below the incombustible substance extraction pipe 6. The apparatus is provided with an incombustible material extraction device 7 provided with a screw conveyor for discharging the incombustible material extracted from 6 to the outside of the incinerator.

In FIG. 1, what is provided above the sand layer 2 is a combustion chamber 8, and what is open to the combustion chamber 8 blows secondary air into the combustion chamber 8. The next air blowing nozzle 9.

The mode of operation of the incinerator having the above configuration will be described below. The refuse introduced into the furnace main body 1 from the refuse inlet is the primary air supplied to the wind box 10 and the air dispersion nozzle 4.
From the sand layer 2 that flows and swirls by being blown from the sand layer, is broken up and gasified by the sand of the sand layer portion 2 and is primarily burned, but the exhaust gas containing unburned gas not burned by the primary combustion rises to the combustion chamber 8 Then, secondary combustion is performed by the secondary air blown from the secondary air blowing nozzle 9 here.

By the way, the flowing and swirling flow of the sand in the sand layer portion 2 is extremely important for complete combustion of the refuse by this kind of incinerator. In other words, it is possible to sufficiently keep the refuse introduced in the sand by the effective flow and swirling of the sand, whereby the refuse can be crushed and gasified without fail.

Therefore, in the incinerator having the above structure, the diameter of the air dispersion nozzle 4 is increased at the center of the dispersion plate 3,
The sand in the sand layer portion 2 is made to flow and swirl from the central portion to the peripheral portion by making it thinner toward the peripheral portion.

Further, as disclosed in Japanese Patent Publication No. 59-22123, in addition to a method of causing concentric swirling flow toward sand to a non-combustible material discharge port, a method for dispersing dust in sand at a position where dust is introduced. Further, there is one that causes a swirling flow.

[0012]

However, in any incinerator, the sand in the sand layer is caused to flow and swirl to a certain state by blowing a fixed amount of air. It can only add strength to the overall flow and swirl of the sand in the area.

As described above, when the flowing and swirling state of the sand is constant, the heat transfer speed from the sand layer portion to the refuse is integrated,
The burning rate of the refuse in the sand layer must be constant,
Even when the amount of waste or the quality of waste related to the level of calories fluctuates greatly, the combustion speed of the waste cannot be adjusted.

Therefore, especially when a large amount of high-calorie refuse is supplied to the incinerator, the burning speed of the refuse in the sand layer portion is too high, so that gasification in the sand layer portion proceeds too much, and a large amount of unburned gas is removed. Since exhaust gas is generated, the exhaust gas is not completely burnt in the combustion chamber above the sand layer, and an unburned gas such as smoke or CO gas is discharged as it is from the incinerator. .

Therefore, an attempt has been made to solve the above problem by combining a moving bed with a small flow of sand and a fluidized bed in which the sand flows normally. Since the movement of the sand is small and the amount of heat transferred from the sand to the waste is small, the burning speed of the waste can be reduced.

Thus, it is possible to prevent the generation of a large amount of unburned gas due to rapid gasification at the time of introducing garbage.
A large amount of unburned refuse remains in the sediment, which increases the combustion load in a normal fluidized bed.

Therefore, the incineration efficiency of the refuse in the total sand layer portion of the incinerator in which the two are combined is reduced. Therefore,
The combustion load on the combustion chamber side above the sand layer will increase, and it will not be possible to absorb the load fluctuations of the larger refuse, and it will not be possible to reliably prevent unburned gas from being discharged outside the incinerator It is.

Accordingly, the present invention relates to an incinerator and an incinerator capable of freely adjusting the combustion speed of the refuse to an optimum state in accordance with fluctuations in the refuse quality according to the amount of the refuse input and the level of calories. The purpose is to provide a driving method.

[0019]

According to the present invention, since the strength of the flow and swirling of the sand in the sand layer is greatly related to the burning speed of the refuse, the flow and whirl of the sand are determined by the amount of the input amount of the refuse and the calorie. It is considered that the above problem can be solved if it is changed in accordance with the fluctuation of the refuse quality according to the height.

Therefore, the configuration of the incinerator according to claim 1 is as follows:
A dispersing plate having a plurality of air distribution nozzles for supporting the sand layer portion on the mortar-shaped upper surface and blowing the primary air into the sand layer portion, wherein a wind box for supplying the primary air to the air distribution nozzle is provided as a dispersion plate. In the fluidized bed incinerator provided with a lower portion and having an incombustible discharge pipe extending downward through a wind box from an incombustible extract outlet provided in the center of the dispersion plate, A partition wall is provided between the inner wall and the outer peripheral wall of the incombustible discharge pipe to divide the wind box into an even number of wind chambers, and a flow rate adjusting damper is provided for each of the primary air supply units to these wind chambers. It is characterized by having been provided.

The gist of the operation method of the incinerator according to the second aspect is that, in the operation method of the fluidized bed type incinerator according to the first aspect, the primary air supply section is provided between the respective air chambers . The opening degree of the air volume adjustment damper is alternately adjusted to vary the air volume of the primary air supplied to each air chamber .

[0022]

According to the incinerator according to the first aspect, a partition wall is provided between the inner wall of the wind box and the outer peripheral wall of the incombustible discharge pipe, and the wind box is divided into an even number of wind chambers. Since the air volume adjusting dampers are provided in each of the primary air supply sections to the air chambers, the opening degree of the air volume adjusting dampers is adjusted to change the air volume to each of the air chambers. 1 blown into
The secondary air volume can be changed for each wind chamber.

According to the operation method of the incinerator according to the second aspect, the opening degree of the air volume adjustment damper provided in the primary air supply section between the respective air chambers is alternately adjusted to adjust the air chambers . Since the air volume of the supplied primary air fluctuates, the sand in the sand layer rises high in areas where the air volume is high, and lowers in areas where the air volume is low, so that the whole sand is wave-like in the circumferential direction. Turn.

[0024]

FIG. 1 shows an embodiment of an incinerator according to the present invention.
6 to FIG. 6, the same components as those of the related art and those having the same functions are denoted by the same reference numerals, and only the differences from the conventional example described in FIG. 7 will be described.

FIG. 1 is an explanatory view of the overall sectional configuration of the incinerator, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. 3 is a sectional view taken along line BB of FIG. As is well understood from these figures, the furnace body 1, dispersion plate 3, incombustible material extraction pipe 6, incombustible material extraction device 7, etc. of the incinerator according to this embodiment are the same as those of the incinerator according to the conventional example. The configuration and the arrangement are exactly the same as in the case, and only the configuration of the wind box 10 is different.

That is, as shown in FIG. 2, the wind box 10 is radially centered on the incombustible discharge pipe 6, one end is on the outer peripheral surface of the incombustible discharge pipe 6, and the other end is the wind box 10 as shown in FIG. Eight air chambers 13 are formed by a partition wall 11 fixed to the inner peripheral wall of the air conditioner, and an air inlet 14 for sending primary air to the air chamber 13 is opened on the side of the incombustible material extraction pipe 6.

As shown in FIG.
A blow duct 15 for feeding primary air supplied from a secondary air blower (not shown) to a blow port 14 opened in each wind chamber 13.
Each of these is provided with an air volume adjusting damper 16.

The air volume adjusting dampers 16 can adjust the opening alternately by interlocking the air volume adjusting dampers 16 interposed in the blowing ducts 15 communicating with the blowing ports 14 of the respective air chambers 13. At the same time, the degree of opening between the air volume adjustment dampers 16 can be changed from large to small and from small to large at predetermined intervals. The interval at which the air flow is switched can be freely set by a timer (not shown) having a well-known configuration.

Therefore, when the opening of the air volume adjusting dampers 16 is adjusted alternately by the interval set by the timer, the change in the air volume of the air chamber 13 will be described with reference to FIGS. 4A and 4B (shown in the air chamber 13). Large and small displays indicate the amount of air flow)
As shown in (5), when a certain air chamber 13 is switched from a large air volume to a small air volume in accordance with the interval, the air chamber 13 adjacent thereto is switched from a small air volume to a large air volume.

Further, by switching the air volume of the wind chamber 13 at a predetermined interval, the wave / swirl state of the sand in the sand layer portion is changed to the wave / swirl state of the sand in the sand layer portion, as shown in FIGS. Each of the partitioned parts shows a wind chamber 13, and
Small display indicates the amount of air flow))
The sand in the sand layer portion 2 located above each wind chamber 13 rises and falls, and the sand in the sand layer portion 2 is shown in FIG. As described above, when the air volume is large, the swirling motion in the sand layer portion is also accompanied by the arrow.

Accordingly, the refuse introduced into the furnace body 1 of the incinerator is taken into the sand of the sand layer 2 which oscillates and swirls in this way, and is dispersed throughout the sand layer 2 to be crushed and gasified. In addition, since the waste is kept in the sand for a long time, it is possible to completely burn the refuse.

Naturally, the air volume and the interval are adjusted according to the amount of waste and the difference in waste quality, but the difference between the small air volume and the large air volume to the air chamber 13 is 1: 1.5 to 2.2. If you adjust it in the range of 0 and the interval between 0.5 and 3 minutes,
It was confirmed that a good effect was obtained for complete combustion of garbage.

The incombustibles in the refuse are turned in the circumferential direction of the furnace body 1 by the wave motion of the sand in the sand layer portion 2 and then collected at the center along the slope of the dispersion plate 3 as in the prior art. The fuel is discharged to the outside of the incinerator by the noncombustible material extraction device 7 through the noncombustible material discharge pipe 5 through the noncombustible material discharge port 5.

On the other hand, the size of the air dispersion nozzles 4 may be the same, or, as in the conventional example described with reference to FIG. A configuration in which a size difference is provided so as to be as thin as possible may be adopted.

As described above, when the size difference is provided in the air dispersion nozzle 4, in addition to the above-described wave motion, the sand moves from the central portion of the sand layer portion 2 to the peripheral portion and the upper portion of the dispersion plate 3. The flow motion returning to the central portion along the slope of the above is added, so that there is an effect that incombustibles in the refuse are more easily collected at the center of the dispersion plate 3.

Next, a wind box according to another embodiment of the present invention.
An example of 10 will be described with reference to FIG. 6 which is a schematic cross-sectional configuration explanatory view. The wind box 10 according to this embodiment is radially centered on the incombustible substance extraction pipe 6 and one end is an incombustible substance extraction pipe. 6 and the other end is partitioned by six partition walls 11 fixed to the inner peripheral wall of the wind box 10, and a concentric wall 12 is provided between the incombustible discharge pipe 6 and the inner peripheral wall of the wind box 10. By providing
The configuration is such that twelve air chambers 13 are formed.

Although not shown in the drawings , each of the air chambers 13 communicates with a blow duct having an air volume adjusting damper in the same manner as in the above embodiment.
The air volume adjustment dampers interposed in the blow ducts communicating with the respective air chambers 13 are linked to each other so as to alternately adjust the opening degree.

In this case, the sand in the sand layer portion 2 can be made to wave more complicatedly than the above embodiment by the combination of the opening degrees of the air volume adjustment dampers. It is easy to understand that it is wider and is superior in performance to the above embodiment.

As described above, by changing the opening degree of the air volume adjustment damper 16, it becomes possible to easily adjust the combustion speed in response to the amount of waste and the quality of waste.
In particular, since rapid combustion due to the introduction of a large amount of high-quality waste is prevented, an extremely large effect was obtained in preventing the generation of unburned gas such as CO gas and dioxins.

[0040]

As described in detail above, claim 1 of the present invention
According to the incinerator according to the above, by providing a partition wall between the inner wall of the wind box and the outer peripheral wall of the incombustible discharge pipe, the wind box is divided into an even number of wind chambers, and Since the air flow adjustment dampers are provided in each of the primary air supply units, the air flow to each air chamber is changed by adjusting the degree of opening of these air flow adjustment dampers so that the air is blown into the sand layer from the air distribution nozzle. The primary air volume can be changed for each air chamber.

According to the operation method of the incinerator according to the second aspect of the present invention, the opening degree of the air volume adjustment dampers provided in the primary air supply section of each air chamber is alternately adjusted, Since the air volume of the primary air supplied to each air chamber is changed, the sand in the sand layer rises high in the area where the air volume is large, and decreases in the circumferential direction while decreasing in the area where the air volume is small. Turn.

Therefore, according to the incinerator according to the present invention, unlike the conventional incinerator, the amount of primary air blown into the sand layer is different from the case where the sand in the sand layer turns at a constant rate. By changing the wave and turning of the sand will be adjusted,
It is possible to completely combust garbage by selecting the optimal flow state, that is, the optimal burning rate, in response to fluctuations in garbage quality in the year and each season, including the amount and quality of garbage,
An extremely great effect can be expected for the reduction of unburned gas such as CO gas and trace harmful substances such as dioxins.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of the overall cross-sectional configuration of an incinerator according to an embodiment.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is an explanatory diagram of a change in air volume in an air chamber.

FIG. 5 is an exploded development view for explaining the wave / turn of the sand in the sand layer portion.

FIG. 6 is a schematic cross-sectional configuration explanatory view of a wind box according to another embodiment.

FIG. 7 is an explanatory sectional view of a typical conventional incinerator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Furnace main body, 2 ... Sand layer part, 3 ... Dispersion plate, 4 ... Air dispersion nozzle, 5 ... Incombustible substance discharge port, 6 ... Noncombustible substance discharge pipe, 7 ... Noncombustible substance discharge device, 8 ... Combustion chamber, 9 … Secondary air blowing nozzle, 10
... wind box, 11 ... partition wall, 12 ... concentric partition wall, 13 ... wind chamber, 14 ...
Inlet, 15… Inlet duct, 16… Air volume adjustment damper.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-290402 (JP, A) JP-A-1-291010 (JP, A) JP-A-62-182515 (JP, A) (58) Investigation Field (Int.Cl. ⁶ , DB name) F23G 5/50 F23G 5/30

Claims (2)

(57) [Claims] 1. A wind plate for supporting a sand layer portion on a mortar-shaped upper surface and having a plurality of air distribution nozzles for blowing primary air into the sand layer portion, and supplying primary air to the air distribution nozzle. In a fluidized bed incinerator provided with a box at the lower part of the dispersion plate and provided with an incombustible discharge pipe extending downward through a wind box from an incombustible outlet provided in the center of the dispersion plate ,
A partition wall is provided between the inner wall of the wind box and the outer peripheral wall of the incombustible substance extraction pipe to divide the wind box into an even number of air chambers, and to supply the primary air to each of these air chambers. A fluidized-bed refuse incinerator characterized by having an air volume adjustment damper. Wherein the opening of the air amount adjusting damper provided in the supply portion of the primary air between Kakukazeshitsu go easy alternately, the air volume of the primary air supplied to Kakukazeshitsu same <br/> mechanic The method for operating a fluidized-bed refuse incinerator according to claim 1, wherein the temperature is varied.