JPH08121758A - Combustion control device - Google Patents

Abstract

PURPOSE: To reduce the exhaust volume of CO and reduce the production of dioxine by grasping the production timing of carbon monoxide at in a secondary combustion region from the image information of the combustion flame, and adjusting the volume of air to be fed to the secondary combustion region for combustion. CONSTITUTION: After a flame region is extracted from the image data by a photographing means 20 to photograph the combustion condition of a combustion part M by a first operating means C1, the image data are decomposed into the color elements of red, green and blue by a second operating means C2, and the intensity ratio of the blue element to the green element is operated and derived for each pixel, and the area of the high temperature region is extracted from the value. Then, the area ratio of the area of the flame region to that of the high temperature region is operated by a third operating means C3 to estimate the production timing of carbon monoxide. Generation of dioxine is effectively suppressed by adjusting the air volume for the secondary combustion by a control means 22 for the produced unburnt gas based on the production timing of CO estimated by a third operating means C3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion control device for an incinerator, and more particularly, to a supply amount of secondary combustion air to a secondary combustion region for completely combusting unburned gas generated in a combustion section or the like. It relates to a combustion control device for adjusting.

[0002]

2. Description of the Related Art Generally, when the amount of combustion air supplied to the secondary combustion region is insufficient or the secondary combustion temperature is lowered, incomplete combustion occurs, and conversely, the combustion air is not supplied to the secondary combustion region. If the supply amount becomes excessive, the cooling effect lowers the secondary combustion temperature and incomplete combustion occurs. Particularly in a refuse incinerator, in order to prevent the generation of dioxin, which is said to have a positive correlation with the amount of carbon monoxide generated, it is important to control the supply of secondary combustion air.

Therefore, in a conventional combustion control device for a refuse incinerator, a gas sensor is installed on the downstream side of an exhaust gas treatment device such as an electric dust collector for removing dust and the like, and based on the detected concentration of carbon monoxide by the gas sensor. Then, there are those which are provided with a control means for adjusting the supply amount of the combustion air to the secondary combustion region and those which are configured to always supply a constant amount of the secondary combustion air.

[0004]

However, in the above-mentioned prior art, particularly in the former case, the detected carbon monoxide concentration is a value that is temporally deviated from the combustion timing in the secondary combustion region. If control is performed based on such a value, the supply timing of the secondary combustion air will be delayed, so there is a problem that it is not possible to effectively prevent the generation of dioxins. However, there is a problem that it is not possible to cope with the dynamic generation of carbon monoxide in order to supply the air.

The object of the present invention is to eliminate the above-mentioned conventional drawbacks, to accurately grasp the generation time of carbon monoxide in the secondary combustion section, and to precisely control the supply amount of combustion air to the secondary combustion section. By providing a combustion control device, the generation of harmful substances such as dioxins can be reduced as much as possible.

[0006]

To achieve this object, the combustion control device according to the present invention is characterized in that an image pickup means for inputting a combustion state in a combustion section and a flame region is extracted from image data obtained by the image pickup means. Image data obtained by the first calculation means and the image pickup means are red (R) green (G)
Decomposed into color components of blue (B), calculated and derived blue in the flame region extracted by the first computing means (B) component and green (G) component intensity ratio (I _B / I _G) for each pixel Then, the second calculation means for extracting the area (S _H ) of the high temperature region from the value, the area (S _F ) of the flame region extracted by the first calculation means and the second calculation means area ratio of the area (S _H) of the high-temperature region (S _H / S _F) was calculated and derived,
Based on the estimation result by the third calculation means for estimating the generation time of carbon monoxide from the calculation result, and the third calculation means,
The control means 22 adjusts the supply amount of the secondary combustion air with respect to the generated unburned gas.

In the above structure, it is preferable that the control means adjusts the heating amount of the unburned gas by the burner mechanism.

Further, the third calculation means is used when the area ( _SH ) of the high temperature area or the area ratio ( _SH / _SF ) is below a set value for a predetermined time, or the area of the high temperature area. It is preferable to estimate that it is the time of generation of carbon monoxide when the reduction rate of ( _SH ) or the area ratio ( _SH / _SF ) becomes equal to or greater than a set value.

[0009]

In general, an object emits a visible amount of visible light at a temperature of about 1000 K or higher, and when the temperature rises, first red, then yellow, green, blue, and finally purple. To the energy of light, a new color part is added to the spectrum. Therefore, by determining the intensity ratio of each wavelength of the combustion flame, it is possible to objectively discriminate between the local high temperature combustion portion and the local low temperature combustion portion. Therefore, the second calculation means decomposes the image data obtained by the image pickup means into color components of red (R) green (G) blue (B), and red (R) including the influence of the background and the like.
Except for components, for each pixel of the extracted region as the flame region by the first computing means, and blue (B) component and green (G) component intensity ratio of the (I _B / I _G) was calculated and derived, the The area ( _SH ) is extracted by setting a pixel having a value larger than a predetermined threshold value as a high temperature area. Incidentally, the extraction of the flame area by the first calculation means, the brightness data may be binarized,
It is also possible to binarize any color component with a predetermined threshold value.

The third calculating means is an area ratio (S _H / S) of the area of the flame region (S _F ) extracted by the first calculating means and the area of the high temperature region (S _H ) extracted by the second calculating means. _F )
Is calculated and the overall combustion state of the combustion flame, that is, the level of the combustion temperature is grasped from the calculation result, and if the combustion temperature is low, the complete combustion of carbon monoxide is hindered due to the decrease in the furnace temperature. Presumed to be in a state. Specifically, when the area ratio (S _H / S _F ) is below a set value for a predetermined time, incomplete combustion occurs due to a decrease in flame temperature, that is, a decrease in furnace temperature, or the area ratio (S _H / S _F )
It is presumed that it is the time when the amount of carbon monoxide generated increases due to incomplete combustion due to lack of oxygen when the decrease rate of is above the set value.

For example, as shown in FIG. 5, when the relationship between the carbon monoxide concentration in the exhaust gas from 10 am to 11 am in the incinerator and the area ratio (S _H / S _F ) of the combustion flame is measured, as shown in FIG. 6, timing where the area ratio (S _H / S _F) is small, the time in which the reduction rate of the area ratio (S _H / S _F) is large is to overlap with the generation timing of the carbon monoxide.

The control means increases the supply amount of the secondary combustion air with respect to the unburned gas generated based on the estimation result of the third calculation means at the time when the generation amount of carbon monoxide increases. By promoting stirring of unburned gas and oxygen, the complete combustion of carbon monoxide is promoted. At that time, if the unburned gas is heated by the burner mechanism provided in the secondary combustion region, the secondary combustion temperature necessary for the combustion of carbon monoxide is secured against the decrease in the temperature inside the furnace and complete combustion is achieved. Can be promoted.

[0013]

Therefore, according to the present invention, the generation timing of carbon monoxide in the secondary combustion region is grasped from the image information of the combustion flame, and the supply amount of the combustion air to the secondary combustion region is accurately adjusted. Thus, it has become possible to provide a combustion control device that can reduce the emission amount of carbon monoxide, and thus the generation of dioxin.

[0014]

EXAMPLES Examples of the combustion control device of the present invention will be described below. As shown in FIG. 4, the refuse incinerator is loaded by a hopper 3 that receives city refuse that is an object to be incinerated, a pusher 4 that throws the dust in the hopper 3 into the furnace from the lower end, and a pusher 4 that is pushed by the pusher 4. A stoker-type incineration zone 5 for incinerating waste while stirring and transporting it is provided, and an air supply means 6 for supplying air for primary combustion from the bottom thereof is provided.

The incineration zone 5 is a hydraulically driven type in which movable grate (not shown) that reciprocates obliquely upward with respect to a fixed grate (not shown) is arranged alternately along the transport direction. The stoker mechanism includes a dry zone L for transporting dust while drying it, a combustion zone M for transporting while burning dust, and a post-combustion zone N for transporting while performing ashing treatment. By making the cycle variable, the transport speed of dust is adjustable.

The air supply means 6 is a blower fan 6a.
The air drawn by the blower 6b is sent to the air box 6c separately provided below the drying zone L, the combustion zone M, and the post combustion zone N, respectively.
The air flow rate is adjustable by providing a damper mechanism 6d on the outlet side of the air flow path 6b to each air box 6c.

The upper part of the incineration zone 5 is constructed as a primary combustion zone 1 for directly incinerating refuse, and a flue formed in the upper space thereof is made a secondary combustion zone 2 for completely burning combustion gas. The nozzle 13a as the secondary combustion air supply mechanism 13 is provided on the flue inlet side to supply the induced air from the blower fan 13b to the flue through the damper mechanism 13c. A burner mechanism 14 for heating the combustion gas in the flue is provided.

A waste heat boiler 12 for recovering the thermal energy of combustion exhaust gas is provided in the space on the downstream side of the secondary combustion region 2 to supply the heat amount generated by combustion to the power generator 11 as steam, while the exhaust gas connected further downstream. Road 7 to chimney 1
An exhaust gas treatment device including a bag filter 8 and a smoke washing device 9 is provided in the middle of the flow path reaching 0.

As shown in FIGS. 1 and 4, in the upper center of the side wall on the downstream side of the incineration zone 5, a color C as an image pickup means 20 for photographing and inputting the combustion state in the combustion zone M.
A CD camera is provided, and an image processing means 21 using a microcomputer for judging the combustion state of dust in the combustion zone M from the image data input by the image pickup means 20 is provided to constitute a combustion state detection device. That is, the combustion zone M becomes the combustion section.

The image processing means 21, as shown in FIG.
First computing means C1 for decomposing the image data input from the imaging means 20 into red (R) green (G) blue (B) color components and extracting a flame region from the green (G) component image data; Second calculating means C2 for calculating and deriving the intensity ratio of the blue (B) component and the green (G) component in the flame area extracted by the first calculating means C1 and extracting the area of the high temperature area from the calculated value.
And the area ratio of the area of the flame region extracted by the first calculating means C1 to the area of the high temperature region extracted by the second calculating means C2, and the combustion zone M is calculated from the calculated value.
The third calculation means C3 for evaluating the combustion state in

Hereinafter, based on the flowchart shown in FIG.
Will be described in detail. The image data input from the image pickup means 20
When decomposed into red (R) green (G) blue (B) color components, FIG.
As shown in (a) and (b), red (R) green for each pixel
(G) Intensity data of blue (B) is obtained <# 1>. General
In addition, the temperature of the object is about 1000K
Emits visible light, and when its temperature rises
The energy of light is red, then yellow, green, blue, and finally purple.
Gee, a new color part is added to the spectrum. combustion
Part, that is, the imaging zone for the combustion zone M in the incinerator.
In the image data obtained by the step 20, other than the flame part,
The temperature of those parts is also included, including the data of the side walls and the dust itself.
Accurate flame only because color components due to
In order to extract into
It is preferable not to refer to the minutes. On the other hand, the blue (B) component is
Since it greatly fluctuates according to the flame temperature, only this component
It is also unfavorable to specify the area of flame more. So before
Note that the first computing means C1 stores the intensity data of the green (G) component.
Constant threshold G _ThThe larger pixel corresponds to the flame area,
That is, the area (S_F<# 2>, <# 3>
>. Here, the threshold value is not particularly limited, and the standard of the furnace is
It may be set appropriately depending on the model and operating conditions.

[0022] The second calculating means C2 is, the intensity ratio of the first calculating means and blue in the flame region extracted by C1 (B) component and green (G) component (I _B / I _G) was calculated and derived , And the pixels whose values are equal to or greater than a predetermined threshold are extracted as the area ( _SH ) of the high temperature region <# 4>, <# 5>.

The area of the flame region (S _F ) extracted by the first operation unit C1 and the area of the high temperature region (S _H ) extracted by the second operation unit C2 are applied to the third operation unit C3. The ratio (S _H / S _F ) is calculated and derived, and from that value the overall combustion state of the combustion flame, that is, the high and low combustion temperatures, is indirectly and quickly grasped, and complete combustion of carbon monoxide is achieved. <# 6>, <# 7> for estimating whether or not the state is inhibited. That is, the third computing means C3
Means that when the area ratio (S _H / S _F ) becomes lower than a set value for a predetermined time, incomplete combustion occurs due to a decrease in flame temperature, that is, a decrease in furnace temperature, or the area ratio (S
It is presumed that it is the time when the amount of carbon monoxide generated increases due to incomplete combustion due to lack of oxygen when the rate of decrease of _{H 2} / _SF ) is above the set value.

The computer-based control means 22 adjusts the damper mechanism 13c of the secondary combustion air supply mechanism 13 on the basis of the estimation result by the third computing means C3 to perform the secondary combustion to the flue. Adjusting the air supply <# 8
>.

For example, the area ratio ( _SH / _SF ) is 0.
When the time of 15 (15%) or less continues for 5 minutes or more, or when the reduction rate of the area ratio ( _SH / _SF ) is 15% or more, the damper opening of the damper mechanism 13c is increased. It is set to increase the air supply amount to promote the stirring of oxygen and carbon monoxide, promote complete combustion in the flue and raise the combustion temperature to promote complete combustion of carbon monoxide. Here, the increase amount of the secondary combustion air is not particularly limited, and may be appropriately set based on the scale and shape of the furnace.

Here, the control method of the air supply amount and the conveyance speed by the control means 22 is not particularly limited, and P
A well-known method such as an ID control method, a fuzzy control method, or an AI control method can be appropriately used. That is, the image pickup means 20, the image processing means 21, and the control means 22 constitute a combustion control device.

Another embodiment will be described below. In the above embodiment, the case where the generation time of carbon monoxide is determined based on the area ratio ( _SH / _SF ) has been described, but it is determined based on the area of the high temperature region ( _SH ) instead of the area ratio. It may be one that does.

In the previous embodiment, the first computing means C1
In the above description, the pixel in which the intensity data of the green (G) component is larger than the predetermined threshold value G _Th is extracted as the pixel corresponding to the flame region, that is, the area (S _F ). The present invention is not limited to this, and the luminance data as a monotone image may be binarized with a predetermined threshold value to extract the flame region, and the intensity data of the red (R) component may be binarized with a predetermined threshold value. It may be configured so as to be binarized to extract the flame region.

In the above embodiment, the third calculating means C3 is used.
Is the area ratio (S_H/ S_F) Is 0.15 (15%) or less
When the lowering time continues for 5 minutes or more, or the area ratio (S
_H/ S _FWhen the reduction rate of) becomes 15% or more,
Carbon monoxide is generated due to incomplete combustion due to lack of oxygen
I explained what is supposed to be the time when the amount increases, but this
These numbers are not particularly limited, and the scale and shape of the furnace
It can be appropriately set according to the shape, the quality of dust, and the like.

Regarding the ignition timing or the combustion temperature of the burner mechanism 14, in addition to the above, the image processing means 21
In addition, a burn-out point calculation means for detecting the burn-off point at which dust moves from gas combustion to solid combustion is provided to ignite or raise the combustion temperature when the burn-off position where dust tends to run out is on the upstream side. It may be adjusted.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part.

FIG. 2 is a characteristic diagram of input image data.

FIG. 3 Flow chart

[Fig. 4] Schematic configuration diagram of a refuse incinerator

FIG. 5 is an explanatory diagram of measurement results.

FIG. 6 is an explanatory diagram of measurement results.

[Explanation of symbols]

 20 image pickup means 22 control means C1 first calculation means C2 second calculation means C3 third calculation means M combustion section

Claims (3)

[Claims] 1. An image pickup means (20) for inputting a combustion state in a combustion section (M), a first calculation means (C1) for extracting a flame region from image data obtained by the image pickup means (20), and the image pickup means. The image data obtained by (20) is decomposed into red (R) green (G) blue (B) color components, and the blue (B) component and green (G) in the flame region extracted by the first calculation means (C1). ) intensity ratio of component (I _B / I _G) was calculated and derived for each pixel, the area of the high-temperature region from that value (second calculating means for extracting the S _H) (C2), said first calculation means ( The area ratio (S _H / S _F ) between the area (S _F ) of the flame area extracted by C1) and the area (S _H ) of the high temperature area extracted by the second operation means (C2) is calculated and derived, A third calculation means (C3) for estimating the generation time of carbon monoxide from the calculation result; Based on the estimation result by the calculation means (C3),
A combustion control device comprising a control means (22) for adjusting the supply amount of secondary combustion air with respect to the generated unburned gas. 2. The combustion control device according to claim 1, wherein the control means (22) adjusts a heating amount of the unburned gas by the burner mechanism (14). 3. The third computing means (C3) is configured to operate when the area (S _H ) or the area ratio (S _H / S _F ) of the high temperature region is below a set value for a predetermined time, or when the high temperature 3. The carbon monoxide generation time is estimated when the reduction rate of the area ( _SH ) or the area ratio ( _SH / _SF ) becomes less than a set value. Combustion control device.