JP2005337556A - Waste material combustion installation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waste material combustion installation for actualizing combustion control while properly determining the combustion condition of refuse charged into a furnace. <P>SOLUTION: The waste material combustion installation comprises an image processing part 35 for applying image processing to the picked-up images of the inside of a fluidized bed combustion furnace 1 for refuse combustion to extract the contour figures of a combustion region, a fractal dimension computing part 36 for finding the fractal dimensions of the contour figures obtained by the image processing part, and a parameter determining part 37 for determining control parameters to control the supply amount of secondary air and the supply amount of refuse in accordance with the fractal dimensions found by the fractal dimension computing part. When the fractal dimension is smaller than a smaller threshold value out of two greater and smaller threshold values showing the range of a normal combustion condition, the supply amount of the refuse and the supply amount of the secondary air are less than those in the normal combustion condition. When the fractal dimension is greater than the greater threshold value, the supply amount of the refuse and the supply amount of the secondary air are controlled to be less and more, respectively, than those in the normal combustion condition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a waste combustion facility.

  Although it is desired to perform stable combustion by controlling the combustion of the waste incineration equipment and suppress the generation of harmful substances such as dioxin, carbon monoxide, NOx, SOx, etc., the properties of the waste (the moisture content) Flammability) is not constant, and the amount charged into the incinerator cannot be constant [the shape, size and density are not uniform, and there is inevitably a large amount of supply to the furnace It is not easy to perform stable combustion control due to various factors such as a complicated combustion state including the distribution of combustion products in the incinerator.

  By the way, in order to suppress the generation of carbon monoxide in the incinerator, the present inventors are in contact with the surface of the waste to be transported, for example, in a screw conveyor for transporting the waste to be put into the fluidized bed waste incinerator. A dust detection plate provided swingably in a vertical plane, and an angle detector that detects an inclination angle with respect to a reference posture of the dust detection plate, and the number of times the detected inclination angle exceeds a predetermined angle and detection Calculate the rate of change in angle and the moving average of the detected angle, and use fuzzy calculation to determine the amount of waste supply and secondary air reference based on the moving average and the number of overshoots, and based on the moving average and rate of change. A waste incineration facility is proposed in which a secondary air correction amount is obtained and combustion control is performed (see Patent Document 1).

This is based on the relationship between the opening of the dust detection plate and the peak of carbon monoxide generation, and the opening of the dust detection plate is used as a sensor for carbon monoxide generation.
In this patent document 1, the reference posture is a posture that is lowered by 30 degrees from the horizontal, and the number of rotations is, for example, a range of postures that are lowered by 21 degrees from the horizontal (the detection plate is 30 when the distance between the reference and the horizontal is 100%) Fuzzy rule that increases the number of times of rotation when the number of times per hour that the dust detection plate is located within the above range is 5 times or more by measuring every second. Has been introduced. When the number of times of overshooting is large, the secondary air reference amount is set to be slightly larger or larger.

  The experimental result in the said structure is shown with the graph of FIG. In FIG. 9, D (solid line) indicates the oxygen concentration, E (thick broken line) indicates the carbon monoxide concentration, and F (broken line) indicates the flapper opening. Note that oxygen is the concentration of unused primary air before secondary air is blown into the freeboard on the fluidized bed, carbon monoxide is the concentration at the latter stage of the bag filter, and the flapper opening is just before supplying garbage to the fluidized bed. The degree of opening of each is detected.

  Moreover, in patent document 2, while photographing the combustion state of the waste thrown into the incinerator with a television camera, the combustion area in this photographed image is made into a fractal dimension, and the combustion is determined based on whether the value is large or not. The quality of the state is judged.

That is, a photographed image of dust on a stoker (grate) in an incinerator is divided into n × n (= number of pixels) square pixels, and these pixels are divided into a predetermined number (n ′ × n ′). When every new pixel (for example, 1 × 1, 2 × 2, 3 × 3, etc.) N obtained by collecting at least one black pixel indicating combustion, the entire new pixel N is burned The total number N is obtained as black pixels. For example, n ′ = 1 pixel level (1 × 1), n ′ = 2 pixel level (2 × 2), n ′ = 4 pixel level (4 × 4), the number N (n = 1 for N = 1, N = 2 for N = 2 and N3 for n = 4, and the fractal dimension is obtained using N1 to N3 (see paragraph numbers 0018 to 0021).
JP 2003-262325 A JP-A-6-229540

  According to the above configuration, the effect of reducing the number of carbon monoxide peaks that has been widely seen in the technology so far has been demonstrated, but from the fact that carbon monoxide peaks still exist, Not enough.

  In addition, as shown in FIG. 9, when the oxygen concentration is lower than a predetermined level, the carbon monoxide peaks are generated with almost the same time delay, so the oxygen concentration is reduced to the carbon monoxide peak generation. As an indicator of this, an attempt was made to improve the supply control of primary and secondary air, but no sufficient improvement was observed. Considering the time difference between the gas flow to the concentration measurement position and the response speed of the measuring instrument, the carbon monoxide concentration will probably increase without much time from when the oxygen concentration is lower than the predetermined level. However, it is considered that there was a delay in the control, which indicates that the oxygen concentration and the carbon monoxide concentration are related.

  In addition, oxygen is used to burn a part of the gas generated by the thermal decomposition of the input waste, so the oxygen concentration seems to change depending on the nature and amount of the input waste. As described above, since it is not always possible to quantitatively supply homogeneous waste, the flapper opening does not necessarily indicate the amount of waste input accurately, and sometimes the waste falls down into the furnace. Also, since the flapper cannot detect the nature of the waste, it does not know how much oxygen the waste requires, so the combustion control can be performed flexibly according to the amount and quality of the waste. Is desired.

Further, according to the configuration of the combustion state monitoring device disclosed in Patent Document 2 described above, it is considered that the problem of “falling” that Patent Document 1 has can be improved, but there are the following problems.
In other words, when the waste to be charged contains a lot of high-calorie components such as plastic, the furnace temperature becomes high (high-temperature combustion), and carbon monoxide is easily generated due to air (oxygen) shortage. In addition, if it becomes high-temperature combustion, it may cause clinker adhesion to the furnace wall, and the removal work may occur at the time of maintenance. There is also a problem that the life of the equipment is adversely affected, such as causing burnout.

  Therefore, the present invention has an object to provide a waste combustion facility capable of appropriately controlling the combustion state of waste introduced into the furnace and performing combustion control, and particularly suitable for high temperature combustion. It aims at providing the combustion equipment which can perform.

In order to solve the above problems, a waste combustion facility according to claim 1 of the present invention includes a combustion furnace for burning waste, a waste supply means for supplying waste to the combustion furnace, and the interior of the combustion furnace. An oxygen supply means for supplying oxygen for combustion, a photographing means for photographing the waste in the combustion furnace, and a photographed image obtained by the photographing means is subjected to predetermined processing to detect the combustion state and Combustion equipment comprising combustion control means for controlling the oxygen supply means and the waste supply means based on the detected combustion state,
The combustion control means is
An image processing unit that inputs a captured image captured by the imaging unit and extracts a contour graphic of the combustion region, a fractal dimension calculation unit that calculates a fractal dimension of the contour graphic obtained by the image processing unit, and the fractal A parameter determining unit that determines control parameters for controlling the oxygen supply amount and the waste supply amount based on the fractal dimension obtained by the dimension calculation unit,
And when determining the control parameters,
When the fractal dimension obtained by the fractal dimension calculation unit is smaller than the smaller threshold of the two large and small thresholds indicating the normal combustion state range, the oxygen supply amount and When the amount of waste input is decreased and the fractal dimension is larger than the larger threshold, the oxygen supply amount is increased and the waste supply amount is decreased compared to the normal combustion state. It is.

  The waste combustion facility according to claim 2 is a fluidized bed type combustion furnace of the combustion facility according to claim 1.

  According to the above configuration, the fractal dimension in the contour figure indicating the waste combustion region is obtained, and two large and small threshold values indicating the normal combustion state range are provided, and the combustion state is detected in three stages. Therefore, it is possible to detect a high-temperature combustion region that has not been detected in the past, and thus it is possible to extend the life of the equipment. If it is, it is optimal.

[Embodiment]
Hereinafter, a waste combustion facility according to an embodiment of the present invention will be described with reference to the drawings.
A combustion facility (also referred to as an incineration facility) for waste (hereinafter also referred to as garbage) according to the present embodiment is a fluidized bed type, and as shown in FIG. 1 is a waste supply device (which is also an example of a waste supply unit, also referred to as a dust supply device) 3 and primary air (combustion) in the lower fluidized bed G of the combustion furnace 1. Primary air supply device (an example of oxygen supply means) 4 for supplying air) and secondary air supply device for supplying secondary air (combustion air) into a combustion space (also referred to as freeboard) 1a of the combustion furnace 1 (An example of oxygen supply means) 5, a camera device (an example of an imaging means, for example, a CCD camera is used) 6 for photographing the combustion state of the waste in the combustion furnace 1, and a waste supply from the waste supply device 3 Enter the amount and the captured image captured by the camera device 6, Even without the operation controller (combustion control unit) 7 for controlling dust supply amount (waste feed amount) and the secondary air supply is provided. In FIG. 1, reference numeral 8 denotes a bag filter provided in an exhaust gas processing unit for introducing exhaust gas from the combustion furnace 1 and performing a predetermined process.

  As the waste supply device 3, a two-shaft screw type feeder provided with two dust transfer screws is used. That is, as shown in FIG. 2 and FIG. 3, the waste supply device 3 is a waste transport space in which two cylinders are arranged in parallel so that parts thereof overlap each other and the cross-sectional shape is a bowl shape. A cylindrical casing 11 in which a chamber 11a is formed, two dust transfer screws 12 rotatably disposed in a dust transfer space chamber 11a formed in the cylindrical casing 11, and each of these screws 12 It is comprised from the electric motor (shown in FIG. 1) 13 to rotate. The dust transfer screw 12 includes a screw blade portion 12 a and a shaft portion 12 b connected to the electric motor 13.

  A dust amount detection device 14 for detecting a dust supply amount (hereinafter also referred to as a dust amount) transported by the dust transport screw 12 is provided in an upper portion of the cylindrical casing 11.

The dust amount detection device 14 is a support shaft body that is rotatably provided in a rectangular frame-shaped mounting portion 11b that protrudes from the upper portion of the cylindrical casing 11 in a direction orthogonal to the direction in which dust is conveyed. 15 and a dust detection flapper (garbage detection plate) 16 whose upper end is attached to the support shaft 15 and whose lower end is supported so as to be swingable in the vertical plane on the dust transport screw 12 side. And an upward inclination angle (hereinafter also referred to as a detection angle) with respect to the rotation angle of the support shaft body 15, that is, the reference posture of the flapper 16 (predetermined angle θ ₀ downward with respect to the horizontal posture). An angle detector (for example, an angle detection encoder is used) 17 for detecting θ. Note that a stopper 19 is provided on the side wall portion of the casing 11 so as to abut on a projecting piece 18 provided at the other end portion of the support shaft 15 and determine the lower limit position of the swing of the flapper 16. The lower edge of the flapper 16 has a shape similar to that of the upper edge of the glasses according to the shape of the screw blades 12a of the two dust transporting screws 12 so that the lower edge of the flapper 16 can be inclined downward to some extent. Has been.

  As shown in FIG. 1, the primary air supply device 4 includes a primary air supply nozzle 21 inserted through a hopper portion 1 b at the bottom of the combustion furnace 1, and a primary air supply pipe 22 connected to the primary air supply nozzle 21. A blower fan 23 for supplying primary air via the air and a damper 24 provided in the middle of the primary air supply pipe 22 for adjusting the amount of primary air supplied into the combustion furnace 1.

  In addition, as shown in FIG. 1, the secondary air supply device 5 includes a secondary air supply nozzle 26 inserted through the intermediate wall 1 c of the combustion furnace 1, and a secondary air nozzle 26. A blower fan 28 for supplying secondary air via an air supply pipe 27 and a damper 29 provided in the middle of the secondary air supply pipe 27 for adjusting the amount of secondary air supplied into the combustion furnace 1. It is configured.

  The dampers 24 and 29 are air supply amount adjusting means, and plate-like damper main bodies 24a and 29a and electric motors 24b for adjusting the amount of air supplied by swinging (driving) the damper main bodies 24a and 29a. 29b.

  Further, the operation control device 7 inputs the detection angle from the angle detector 17 provided in the dust supply device 3, and the rotational speed (number of rotations) of the electric motor 13 that drives the screw blade 12 and at least the secondary air. The control parameter for adjusting the amount is obtained by fuzzy calculation, and the contour figure of the combustion region extracted from the captured image of the combustion dust captured by the camera device 6 is fractalized to detect (determine) the combustion state more accurately. Therefore, the waste supply amount and the secondary air amount are optimally controlled.

Normally, the primary air is also controlled (by fuzzy control similar to the secondary air shown below), but in this embodiment, the description of the primary air control is omitted.
Hereinafter, the operation control device 7 will be described in detail.

  As shown in FIG. 4, the operation control device 7 has the number of times that the detected angle θ of the flapper 16 detected by the angle detector 17 exceeds (exceeds) a predetermined ratio (predetermined set angle). The number-of-turns detection unit 31 for detecting the angle, the angle change rate detection unit 32 for detecting the change rate of the detection angle θ of the flapper 16, the moving average detection unit 33 for calculating the moving average of the detection angle θ of the flapper 16, The detection values obtained by the detection units 31 to 33 are input, and the fuzzy calculation unit 34 that calculates the dust supply amount and the secondary air supply amount based on the fuzzy rules, and the image taken by the camera device 6 An image processing unit 35 that inputs an image and performs predetermined image processing and extracts a contour figure of a burning region of dust, and a fractal dimension for obtaining a fractal dimension of the contour figure extracted by the image processing unit 35 Inputs the waste supply amount and secondary air supply amount, which are outputs from the calculation unit 36 and the fuzzy calculation unit 34, and the fractal dimension, which is the output from the fractal dimension calculation unit 36, according to the value of the fractal dimension. The parameter determination unit 37 determines the final control parameter by changing the output from the fuzzy calculation unit 34 (with correction). Of course, this control parameter instructs the waste supply device 3 to supply the waste supply amount and the secondary air supply device 5 to supply the secondary air supply amount, respectively.

First, the fuzzy computing unit 34 will be described.
When the detection values from the detection units 31 to 33 are input to the fuzzy calculation unit 34, “small (small)”, “medium”, and “large (large)”, respectively, based on a membership function prepared in advance. Output (preceding part condition) is obtained, and each output is input, and the waste supply control rule provides the output of the waste supply amount, and the secondary air reference amount control rule and the secondary According to the air correction amount control rule, outputs of the secondary air reference amount and the secondary air correction amount are obtained, and these outputs are added to obtain the output of the secondary air supply amount.

  In other words, the fuzzy computing unit 34 is configured to include a waste supply amount computing unit 41 that obtains a waste supply amount in the waste supply device 3 based on the moving average of the detection angle of the flapper 16 and the number of times of rotation of the flapper 16. The secondary air reference amount calculation unit 42 for obtaining the secondary air reference amount in the secondary air supply device 5 based on the above, and the secondary air correction amount in the secondary air supply device 6 based on the moving average and the rate of change. A secondary air correction amount calculation unit 43 that calculates the secondary air reference amount and the secondary air correction amount, and an addition unit 44 that calculates the secondary air supply amount by adding the secondary air reference amount and the secondary air correction amount. As described above, the parameter for controlling the electric motor 13 that rotates the screw blade portion 12 in the dust supply device 3 based on the dust supply amount from the dust supply amount calculation unit 41. Is outputted, the parameter for controlling the electric motor 29b for adjusting the damper body 29a in the secondary air supply device 5 on the basis of the secondary air supply from the addition section 44 is output. Of course, when the primary air supply amount is controlled, a parameter for controlling the electric motor 24b for adjusting the damper main body 24a in the primary air supply device 4 is output.

Here, the fuzzy rule for determining the consequent part output will be briefly described.
The control rules for determining the rotational speed of the dust conveying screw 12 at the time of waste supply have input values of “low / medium / high” of the moving average of the flapper 16 and “small / medium / large” of the number of times of rotation of the flapper 16. As a result, the amount of waste supplied by the waste supply device 3, that is, the rotation speed of the electric motor 13 that rotates the screw 12 for conveying the waste is output in five stages (less, somewhat less, current status, slightly more, more). For example, when the moving average is “high” and the number of times of excess is “small”, an output that the amount of waste supply should be “slightly large” is obtained. Therefore, based on the output of “slightly more”, a range of rotational speed (for example, a membership function) corresponding to five stages is determined in advance, and the rotational speed is within this rotational speed range. A control command is output to the electric motor 13 of the dust conveying screw 12.

  In addition, the control rule for obtaining the secondary air reference amount is set to input values for the low, medium, and high flapper moving averages and the low, medium, and high number of flapper movements. The amount is output in 5 stages (less, somewhat less, current status, slightly more, more). For example, when the moving average is “high” and the number of overruns is “small”, an output that the secondary air reference amount should be “somewhat small” is obtained.

  In addition, the control rule for obtaining the secondary air correction amount is the secondary air correction by using the input values of “low / medium / high” of the flapper moving average and “small / medium / large” of the change rate of the flapper. The amount is output in 5 stages (less, somewhat less, current status, slightly more, more). For example, when the moving average is “high” and the change rate is “small”, an output indicating that the secondary air correction amount should be “somewhat small” is obtained.

The output obtained by adding the secondary air correction amount to the output of the secondary air reference amount by the adding unit 44 is output to the parameter determining unit 37 as a control parameter.
The secondary air reference amount is a basic portion (amount) of the supplied secondary air amount, while the secondary air correction amount is an auxiliary portion (amount) for the basic portion. For example, the ratio between the secondary air reference amount and the secondary air correction amount is, for example, 80:20. For example, the secondary air correction amount is “slightly less” (second among the five levels). Is output as the correction amount, [20/5 (stage)] × 2 (stage) = 4, and when the secondary air reference amount is 80, which is the largest. , 80 + 2 = 82 is output as the secondary air supply amount. That is, assuming that the supplyable secondary air amount is 100%, 82% of the secondary air amount is supplied.

  The image processing unit 35 includes an image capturing unit (also an interface unit) 51 that captures a captured image, a binarization processing unit 52 that performs binarization processing on the image captured by the image capturing unit 51, A labeling processing unit 53 that performs labeling processing on the binarized image binarized by the binarization processing unit 52, and an edge processing unit 54 that performs edge processing on the image that has been labeled by the labeling processing unit 53. It consists of and.

  In the binarization processing unit 52, an average value of three RGB values (respectively represented by values of 0 to 255) in each pixel of the captured image (which is a color image) is calculated for each pixel. The brightness is black when the brightness exceeds a predetermined threshold (for example, 40% of the maximum brightness (255)), and white when the brightness is smaller than the threshold. Further, in the edge processing unit 54, a contour graphic (frame line) of the combustion region is extracted using a commonly used method, for example, a Laplacian equation.

Next, the fractal dimension calculation unit 36 will be described in detail.
First, the fractal dimension will be described.
The fractal dimension is derived from the Hausdorff measure, and when a certain figure X is approximated using a straight line having a length d (which is an example of a covering distance), for example, in the present embodiment, the length of one side. Is a square of d (the covering distance in this case is √2 × d), and the number (covering number) of covering is N (d), the Hausdorff measure M ^k (X) is as follows (1 ) Expression.

そして、或る数ｋ_０において、種々の長さｄと当該長さｄに対する個数Ｎ（ｄ）との間に、下記（２）式に示すような比例関係があるとすると、下記（３）式が得られる。

If a certain number k ₀ has a proportional relationship as shown in the following equation (2) between various lengths d and the number N (d) with respect to the length d, the following (3) The formula is obtained.

但し、長さｄと個数Ｎ（ｄ）との間に、上記（２）式の比例関係が成立するような値ｄが採用される。

However, a value d is employed between the length d and the number N (d) so that the proportional relationship of the above equation (2) is established.

From the above equations (1) and (3), the Hausdorff measure M ^k (X) of the graphic X is expressed by the following equation (4) when k = k ₀ .

そして、上記（４）式における定数ｋ_０をフラクタル次元とするものである。

The constant k ₀ in the above equation (4) is set as the fractal dimension.

By the way, the constant k ₀ can be obtained by taking the natural logarithm of both sides of the above equation (2).
Taking the natural logarithm of both sides of the above equation (2), the following equation (5) is obtained.

logN (d) = − k ₀ logd + logμ (5)
When logN (d) in this equation (5) is replaced with y and logd is replaced with x, the following equation (6) is obtained.

y = −k ₀ x + log μ (6)
Then, by calculating a regression line by substituting a plurality of actual measurement data into x (logd) and y (logN (d)), k ₀ is given as the slope of the regression line. Become.

Hereinafter, the configuration of the fractal dimension calculation unit 36 will be described in consideration of the above-described procedure.
The fractal dimension calculation unit 36 uses an image from which an outline figure has been extracted with the length of one side d (a plurality of values are used, for example, the length of one side is changed by the number of pixels (pixels)). A square section 61 that is partitioned by a certain square (specifically, a plurality of types of squares having different sizes such as 2 pixels × 2 pixels, 4 pixels × 4 pixels, 8 pixels × 8 pixels, etc.), The number calculation unit 62 for obtaining the number N (d) of squares including the contour figure of the image divided by the square division unit 61, the value of each length d (number of pixels), and the number calculation unit 62 The logarithmic operation unit 63 for obtaining the natural logarithm by inputting the obtained number N (d), and corresponding to the slope (numerical value) of the regression line based on the x and y values obtained by the logarithmic operation unit 63. k 0 consists dimension computing section 64. for calculating the _(fractal dimension) It has been.

Next, the calculation procedure of the fractal dimension in the fractal dimension calculation unit 36 will be described with reference to FIG.
First, an outline graphic (a fractal graphic X for calculating complexity) U _i (shown in FIG. 5A) obtained by edge processing in the image processing unit 35 with a predetermined length d interval. A square having a predetermined length d on one side is formed throughout the grid. When the length of one side is 2 pixels (d = 2) in FIG. 5B, when the length of one side is 4 pixels (d = 4) in FIG. 5C, the length of FIG. The case where the length of one side is 8 pixels (d = 8) is shown.

Next, after obtaining the number N (d) for various lengths d by the number computation unit 62, the log computation unit 63 obtains logd and logN (d). Then, these plural sets of logd and logN (d) are input to the dimension calculation unit 64 to obtain the fractal dimension k ₀ which is the slope of the regression line of each data (shown in FIG. 6, in this case, the slope, that is, the fractal). dimension _{k 0} is 1.322).

  FIG. 5 shows a normal combustion state. FIG. 7 shows a combustion state when dust is dropped. FIG. 8 shows a high heat generation material (high calorie material) such as plastics. It shows the high temperature combustion state that is burning.

For example, when the trash is dropped, as shown in FIG. 7, it can be seen that the flame fluctuates, the luminance changes, etc., and the image is disturbed before the screen becomes dark. The fractal dimension k ₀ is also 1 It was a large value of .45.

Further, when the waste is a highly exothermic material such as plastics, as shown in FIG. 8, the brightness in the furnace is increased in a state of excessive combustion, and oxygen is insufficient. In this case, it can be seen that the value of the fractal dimension k ₀ is 1.18, which is smaller than that in the normal combustion state.

Then, as described above, the fractal dimension k ₀ obtained by the fractal dimension calculation unit 36 is input to the parameter determination unit 37, and the dust supply amount and the secondary air supply amount, which are outputs from the fuzzy calculation unit 34, are obtained. Then, a correction according to the value of the fractal dimension is added to change the output.

Specifically, the fractal dimension k ₀ is compared based on two large and small threshold values indicating the range of the normal combustion state.
In other words, the fractal dimension k ₀ is the magnitude threshold (e.g., 1.25 to 1.35) if, but not to change the waste supply rate and the secondary air supply, toward the fractal dimension k ₀ is smaller When it is smaller than the threshold value (1.25), the dust supply amount is decreased and the secondary air supply amount is also decreased. Further, when the fractal dimension k ₀ is larger than the larger threshold value (1.35) (for example, in the case of some drop), the dust supply amount is decreased and the secondary air supply amount is increased. Note that the primary air supply amount is similarly increased or decreased in accordance with the increase or decrease of the secondary air supply amount.

  As described above, the combustion state of the waste in the furnace is detected (judged) using the fractal dimension of the contour figure indicating the combustion region, and within the range of the fractal dimension indicating the normal combustion state, the range smaller than that. In addition, since the detection is performed based on a total of three ranges including the larger range, it is possible to detect a high-temperature combustion state that is determined to be a normal state in the prior art, and accordingly, the high-temperature combustion state is detected. Since it can be removed quickly, the life of the combustion furnace can be extended, and adhesion of clinker and the like can be prevented to facilitate maintenance and inspection work. That is, more optimal combustion control can be performed.

In particular, when the above-described combustion control is applied to a fluidized bed type combustion furnace, it is very effective as compared to a case where it is applied to a grate type combustion furnace.
For example, in a grate-type combustion furnace, it takes about 40 minutes from the introduction of dust to the completion of combustion (drying, combustion, and post-combustion), and because the grate area is large and the amount of combustion air is large, it happens to be high. Even when calorie waste is introduced, the gas components discharged from the combustion furnace are unlikely to fluctuate violently except that the temperature rises locally and adversely affects the grate.

  However, in the fluidized bed combustion furnace, the time from the input of the waste to the combustion is as short as about 1 second, and the discharged gas component is greatly affected by the properties of the waste, even if the amount of waste input is the same. When considering control at a later stage of processing the exhaust gas, it is preferable to stabilize the exhaust gas component quickly.

  In other words, in a fluidized bed combustion furnace, the components of the exhaust gas also fluctuate violently because the speed is fast from waste input to combustion and the quality of the waste is not uniform. It is difficult to suppress the generation of carbon.For example, if the garbage falls down, the amount of garbage increases rapidly. The hearth temperature is lowered and the combustion state is deteriorated. That is, the fluidized bed combustion furnace needs to perform appropriate control in real time in accordance with the combustion state that changes from moment to moment, and is exactly the optimum combustion furnace for applying the above-described combustion control.

The portion for determining the fractal dimension k ₀ as described above in the operation control device 7 is executed by a computer device on which the program is provided.
As described above, the fractal dimension in the contour figure that is the extension of the combustion region of the dust is obtained, and two large and small threshold values indicating the range of the normal combustion state are provided to detect the combustion state in three stages. Therefore, it is possible to detect a high-temperature combustion state (high-temperature combustion region) that has not been detected in the prior art, thus extending the life of the combustion furnace and suppressing adhesion of the clinker or the like to the furnace wall be able to. That is, optimal combustion control can be performed in a fluidized bed combustion furnace.

  In the above embodiment, when the fractal dimension exceeds a predetermined value, the parameter determination unit 37 modifies the secondary air supply amount and the dust supply amount output from the fuzzy calculation unit 34. Although the output has been described as being changed, for example, when the fractal dimension exceeds a predetermined value, the predetermined dust supply amount and secondary air supply amount are replaced instead of the output from the fuzzy calculation unit 34. Then, it may be output from the parameter determination unit 37.

  In the above embodiment, the combustion control is performed by adjusting the supply amount of the combustion air (primary air and secondary air). For example, instead of the combustion air, It may be one that adjusts the amount of oxygen supplied (an example of an oxygen supply means), and the combustion air may be oxygen-enriched air.

It is a figure which shows schematic structure of the refuse combustion equipment which concerns on embodiment of this invention. It is a principal part side view of the refuse supply apparatus in the refuse combustion equipment. It is AA sectional drawing of FIG. It is a block diagram which shows schematic structure of the operation control apparatus in the waste combustion equipment. It is a graph explaining the calculation procedure in the same fractal dimension calculation part. It is a graph which shows the fractal dimension in the same fractal dimension calculating part. It is a graph explaining the calculation procedure in the same fractal dimension calculation part. It is a graph explaining the calculation procedure in the same fractal dimension calculation part. It is a graph which shows the oxygen concentration, flapper opening degree, and carbon monoxide concentration in the combustion furnace which concerns on a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fluidized bed type combustion furnace 3 Waste supply apparatus 5 Secondary air supply apparatus 6 Camera apparatus 7 Operation control apparatus 12 Waste conveyance screw 13 Electric motor 14 Waste amount detection apparatus 16 Flapper 17 Angle detector 27 Secondary air supply pipe 29 Damper 31 Number of rotations detection unit 32 Angle change rate detection unit 33 Moving average detection unit 34 Fuzzy calculation unit 36 Fractal dimension calculation unit 37 Parameter determination unit 41 Waste supply amount calculation unit 42 Secondary air reference amount calculation unit 43 Secondary air correction amount calculation unit 44 adder 51 image capture unit 52 binarization processing unit 53 labeling processing unit 54 edge processing unit 61 square section 62 number determination unit 63 logarithmic operation unit 64 dimension operation unit

Claims (2)

A combustion furnace for burning waste, a waste supply means for supplying waste to the combustion furnace, an oxygen supply means for supplying combustion oxygen into the combustion furnace, and photographing the waste in the combustion furnace An imaging unit and a combustion control unit for performing a predetermined process on the captured image obtained by the imaging unit to detect a combustion state and controlling the oxygen supply unit and the waste supply unit based on the detected combustion state A combustion facility comprising:
The combustion control means is
An image processing unit that inputs a captured image captured by the imaging unit and extracts a contour graphic of the combustion region, a fractal dimension calculation unit that calculates a fractal dimension of the contour graphic obtained by the image processing unit, and the fractal A parameter determining unit that determines control parameters for controlling the oxygen supply amount and the waste supply amount based on the fractal dimension obtained by the dimension calculation unit,
And when determining the control parameters,
When the fractal dimension obtained by the fractal dimension calculation unit is smaller than the smaller threshold of the two large and small thresholds indicating the normal combustion state range, the oxygen supply amount and The amount of waste input was reduced, and when the fractal dimension was larger than the larger threshold, the oxygen supply amount was increased and the waste supply amount was decreased compared to the normal combustion state. Waste combustion equipment characterized by The waste combustion facility according to claim 1, wherein the combustion furnace is of a fluidized bed type.

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