JP4194962B2 - Volume reduction equipment, its operation control device, and operation control program - Google Patents

Description

  The present invention relates to a volume reduction facility having a furnace for reducing the volume of an object to be reduced by heat, an operation control device thereof, and an operation control program.

  It is desired to suppress the generation of harmful substances such as dioxin, carbon monoxide, NOx, SOx by controlling the combustion of the waste incineration facility, but the properties of the waste (the moisture, (Flammability) is not constant, and the amount charged into the incinerator cannot be constant [the shape, size, and density are not uniform, and a large amount of supply (sudden drop) into the furnace inevitably occurs. ], 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 overturns 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.
JP 2003-262325 A

  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 mentioned 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. Considering that the oxygen concentration is a good representation of the consumption state, it is desirable to perform stable combustion control by capturing changes in the oxygen concentration.

  Accordingly, an object of the present invention is to provide a volume reduction facility capable of reducing the number of occurrences of peaks by detecting a precursor of the peak occurrence of carbon monoxide, an operation control device thereof, and an operation control program. Another object of the present invention is to provide stable control by converting a change in oxygen concentration over time into a numerical value of a different dimension when detecting the precursor.

In order to solve the above problems, a volume reduction facility according to claim 1 of the present invention supplies a furnace for volume reduction by applying heat to the volume reduction object, and supplies the volume reduction object to this furnace. A volume reduction facility comprising a processing object supply means, an oxygen concentration meter that measures the oxygen concentration in the furnace, and an operation control device that performs a volume reduction operation of the furnace based on the detected oxygen concentration. ,
The operation control device includes a storage unit for storing the oxygen concentration measured by the oximeter in time series, and a fractal dimension calculation for obtaining a fractal dimension of an oxygen concentration curve obtained from the stored time series oxygen concentration data. And a parameter determination unit for determining a control parameter for volume reduction operation based on the fractal dimension obtained by the fractal dimension calculation unit.

  In the volume reduction facility according to claim 2, the furnace in the facility according to claim 1 is a waste incinerator, and the control parameter is at least the amount of air or oxygen supplied into the waste incinerator. is there.

  In the volume reduction facility according to claim 3, the furnace in the facility according to claim 1 is a melting furnace, and the control parameter is at least the amount of air or oxygen supplied into the melting furnace.

According to a fourth aspect of the present invention, there is provided an operation control apparatus comprising: the oxygen concentration provided in the furnace of the volume reduction facility for supplying the volume reduction treatment object to the furnace by the treatment object supply means and applying heat to reduce the volume. An operation control device for performing a volume reduction operation of a furnace based on an oxygen concentration measured by a meter,
A storage unit that stores the oxygen concentration measured by the oximeter in time series, a fractal dimension calculation unit that calculates a fractal dimension of an oxygen concentration curve obtained from the stored time-series oxygen concentration data, and the fractal dimension Among the control parameters of the volume reduction operation based on the fractal dimension obtained by the calculation unit, the parameter determination unit is configured to determine at least the supply amount of the processing object.

Furthermore, the operation control program according to claim 5 is a furnace for reducing the volume by applying heat to the volume reduction object, a process object supply means for supplying the volume reduction object to the furnace, An oxygen concentration meter that measures the oxygen concentration in the furnace and an operation control device that performs a volume reduction operation of the furnace by obtaining a fractal dimension of the oxygen concentration curve obtained from the measured time-series oxygen concentration data. A control program for the operation control device in the storage facility,
A data storage function for storing time-series oxygen concentration data measured by the oximeter in the storage unit, and inputting the time-series oxygen concentration data stored in the storage unit to obtain an oxygen concentration curve within a predetermined time. The curve calculation function to be obtained, the number calculation function to obtain the number of coatings of the curve with respect to various coating distances for the oxygen concentration curve obtained by the curve calculation function, the value of each coating distance and the number calculation function Logarithm calculation function to obtain the natural logarithm by inputting the number of coverings, and the fractal dimension corresponding to the logarithmic value of the covering distance and the slope of the regression line obtained from the logarithmic value of the covering number And a dimension calculation function for obtaining.

  According to each of the above configurations, by determining the fractal dimension in the oxygen concentration curve obtained from time-series oxygen concentration data, carbon monoxide generation can be predicted, and carbon monoxide generation can be further suppressed. In addition, since the control parameter is determined by using a fractal dimension having a gentle value, it is possible to prevent the control parameter from being frequently changed, and thus more stable control can be performed.

[Embodiment]
Hereinafter, a volume reduction facility, an operation control device thereof, and an operation control program according to an embodiment of the present invention will be described with reference to the drawings.

In the present embodiment, a case where a waste incineration facility is used as the volume reduction facility will be described.
The waste incineration facility according to the present embodiment is of a fluidized bed type. As shown in FIG. 1, the fluidized bed incinerator 1 and the garbage provided in the incinerator 1 (an example of a volume reduction treatment target) Primary air (combustion air) is supplied into a waste fluid supply device (which is also an example of a processing object supply means, also referred to as a dust supply device) 3 and a lower fluidized bed G of the incinerator 1. Primary air supply device 4, a secondary air supply device 5 for supplying secondary air (combustion air) into a combustion space (also referred to as free board) 1 a of combustion furnace 1, and a position lower than the secondary air supply position In the exhaust gas in the rear stage of the bag filter 7 provided in the oxygen concentration meter 6 for measuring the oxygen concentration in the combustion space 1a of the gas and the exhaust gas processing unit for guiding the exhaust gas from the incinerator 1 and performing a predetermined treatment Carbon monoxide concentration meter for measuring carbon monoxide concentration If, by entering the waste feed rate and the measured oxygen concentration from the waste feeder 3, and the operation control unit 9 for controlling at least dust supply amount and the secondary air supply is provided.

  As the waste supply device 3, a twin screw type feeder provided with two waste transporting 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 13 (it is an example of a drive part, which is shown in FIG. 1) 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 on the dust transporting screw 12 side so as to be swingable in a vertical plane. 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 that is inserted through a hopper 1 b at the bottom of the incinerator 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 incinerator 1.

  Further, as shown in FIG. 1, the secondary air supply device 5 includes a secondary air supply nozzle 26 inserted through the intermediate wall portion 1 c of the incinerator 1, and a secondary air nozzle 26. A blower fan 28 for supplying secondary air via the 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 incinerator 1. It is configured.

  Each of the dampers 24 and 29 is an example of an air supply amount adjusting unit, and adjusts the plate-like damper main bodies 24a and 29a and the amount of air supplied by swinging (driving) the damper main bodies 24a and 29a. It is comprised from the electric motor (drive part) 24b, 29b.

  Further, the operation control device 9 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 time series oxygen concentration data measured by the oxygen concentration meter 6 is fractalized to predict the peak generation of carbon monoxide. The amount is optimally controlled.

  Normally, the primary air is also controlled (for example, by fuzzy control similar to the secondary air described below), but in this embodiment, the description of the primary air control is omitted.

Hereinafter, the operation control device 9 will be described in detail.
As shown in FIG. 4, the operation control device 9 has a 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, Each detection value obtained by the detection units 31 to 33 is input, and a fuzzy calculation unit 34 for calculating the dust supply amount and the secondary air supply amount based on the fuzzy rules, and the detection angle θ of the flapper 16 and the oxygen concentration meter 6 stores the oxygen concentration from at least a predetermined time (more precisely, the data at the newest predetermined time) in time series, and from this storage unit 35, for example, stores the oxygen concentration data at the maximum. Are a fractal dimension calculation unit 36 that obtains a predetermined amount of time and converts it into a fractal dimension, and a dust supply amount and a secondary air supply amount that are outputs from the fuzzy calculation unit 34, and an output from the fractal dimension calculation unit 36. A fractal dimension is input, and a parameter determining unit 37 that determines the final control parameter by changing (adding correction) the output from the fuzzy computing unit 34 according to the value of the fractal dimension. . Of course, this control parameter instructs the waste supply device 3 to supply the waste and the secondary air supply device 5 to supply the secondary air.

First, the fuzzy computing unit 34 will be described.
When the detection values are input from the detection units 31 to 33 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 also 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.

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. When a certain figure X is approximated by using a straight line of length (an example of a covering distance, hereinafter referred to as a diameter) d (specifically, a diameter Assuming that N (d) is the number (when covered with a circle d), the Hausdorff measure M ^k (X) is expressed by the following equation (1).

そして、或る数ｋ_０において、種々の直径ｄと当該直径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 there is a proportional relationship as shown in the following equation (2) between various diameters d and the number N (d) with respect to the diameter d at a certain number k ₀ , the following equation (3) is obtained. can get.

但し、直径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 used between the diameter d and the number N (d) such 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 figure X is expressed by the following equation (4) when k = k ₀ .
M ^k0 (X) ^≈μ (4)
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.
As shown in FIG. 5, the fractal dimension calculation unit 36 is based on a plurality of time-series oxygen concentration data (x, y data) accumulated in the storage unit 35 within a predetermined time (also a predetermined number of measurements). A curve calculation unit 51 for obtaining an oxygen concentration curve (corresponding to the figure X), a number calculation unit 52 for obtaining the number N (d) for various values of the diameter d for the oxygen concentration curve obtained by the curve calculation unit 51, The logarithm calculation unit 53 for obtaining the natural logarithm by inputting the value of each d and the number N (d) obtained by the number calculation unit 52, and the x and y values obtained by the logarithm calculation unit 53 The dimension calculation unit 54 calculates k ₀ (fractal dimension) corresponding to the slope (numerical value) of the regression line based on each value.

Next, the calculation procedure of the fractal dimension in the fractal dimension calculation unit 36 will be described with reference to FIGS.
First, the oxygen concentration value from the oximeter 6 accumulated in the storage unit 35 is fetched into the curve calculation unit 51 by a predetermined number (the number of data collected in a predetermined measurement time) from the latest one, and coordinates in time series An oxygen concentration curve (which is a fractal figure X for determining complexity) U _i is obtained by arranging and curving the upper part (shown in FIG. 6A). Next, after determining the number N (d) for various diameters d by the number calculation unit 52 (FIG. 6B to FIG. 6D, d (diameter of the circle R) is 3, 10, 15) And only a part of the circle R is shown), and the logarithmic calculator 53 obtains logd and logN (d). Then, these plural sets of logd and logN (d) are input to the dimension calculation unit 54 to obtain the fractal dimension k ₀ which is the slope of the regression line of each data (shown in FIG. 7, in this case, the slope, that is, the fractal). dimension _{k 0} is 1.0882).

FIG. 8 shows the fractal dimension k ₀ obtained by the fractal dimension calculation unit 36 using 60 oxygen concentrations C (data per second, indicated by a solid line) when the oxygen concentration and the measurement time are 60 seconds. A curve A (indicated by a thick solid line) and a carbon monoxide concentration curve B (indicated by a thick broken line) are shown.

  From FIG. 8, a peak of carbon monoxide concentration B appears about 1 minute after the oxygen concentration C falls below about 4.5 (vol%). This is from the distance of the gas sampling position and the sampling position. Considering the channel length to the oxygen concentration meter and the carbon monoxide concentration meter, and the response speed of each concentration meter, it can be seen that the generation occurred almost without time.

Here, looking at the left side (temporally in front) from the position where the oxygen concentration C is less than about 4.5 (vol%), it is not known from the value of the oxygen concentration, but some of the fractal dimension A is excluded. It can be seen that about 1.2 or more is shown 4 to 5 minutes ago. In FIG. 8, three out of five carbon monoxide peaks are applicable. This indicates that the peak of generated carbon monoxide can be predicted although it is not perfect, and the change in the fractal dimension (k ₀ ) A is much more gradual than the change in the oxygen concentration C. I understand that

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 waste supply amount and the secondary air supply amount, which are outputs from the fuzzy calculation unit 34, In addition, a correction according to the value of the fractal dimension is added to change the output.

In other words, the fractal dimension k ₀ is a predetermined value (e.g., 1.2) is less than, but not to change the waste supply rate and the secondary air supply, if the fractal dimension k ₀ is accustomed to more than a predetermined value In addition, the waste supply amount is decreased, the secondary air supply amount is increased, and the primary air supply amount is also increased.

The change of this parameter is stopped when a predetermined time (for example, about 4 to 5 minutes) elapses or when the fractal dimension k ₀ falls below a predetermined value. As described above, since the fractal dimension k ₀ shows a gradual change, the control parameter output from the fuzzy computing unit 34 is not frequently changed, and thus stable combustion control can be performed.

Meanwhile, the portion for obtaining the fractal dimension k ₀ as described above in the operation control unit 9 is normally to be executed by a computer device, The following describes the execution program.

That is, the control program of the operation control device 9 includes an incinerator 1 that reduces the volume of waste by applying heat to the waste (volume reduction target), and a waste supply device that supplies the waste to the incinerator 1 (processing) (Object supply means) 3, an oxygen concentration meter 6 for measuring the oxygen concentration in the incinerator 1, and the combustion of the furnace by obtaining the fractal dimension of the oxygen concentration curve obtained from the measured time-series oxygen concentration data A control program for the operation control device in a waste incineration facility (volume reduction facility) having an operation control device 9 for performing operation (volume reduction operation),
A data storage function for storing time-series oxygen concentration data measured by the oxygen concentration meter 6 in the storage unit 35, and input of the time-series oxygen concentration data stored in the storage unit 35 for oxygen within a predetermined time A curve calculation function for obtaining a concentration curve (a function performed by the curve calculation unit), and a number calculation for determining the number of coatings N (d) of the curve with respect to various coating distances d for the oxygen concentration curve obtained by this curve calculation function Logarithm calculation function (function performed in the logarithm calculation unit) that calculates the natural logarithm by inputting the function (function performed in the number calculation unit) and the value of each covering distance and the number of covers obtained by this number calculation function ) And a dimension calculation function (dimension calculation unit) for obtaining a fractal dimension k ₀ corresponding to the slope of the regression line obtained from the logarithmic value of the covering distance and the logarithmic value of the covering number obtained by the logarithmic calculation function The functions performed in the above are provided.

  As described above, by obtaining the fractal dimension in the oxygen concentration curve from the time-series oxygen concentration data, the peak generation of carbon monoxide can be predicted, and the peak generation of carbon monoxide can be suppressed more than ever. In addition, since the control parameter is determined using a fractal dimension having a gentle value, the control parameter is prevented from being frequently changed, and thus stable control can be performed.

More specifically, it is as follows.
In other words, it is difficult to always supply the waste (volume reduction target) to the furnace with a constant supply amount and properties, so the oxygen concentration changes rapidly with time. The oxygen concentration correctly reflects the nature and amount of waste. As described above, the amount of waste and its properties that are thrown into the incinerator are not constant, and the amount of oxygen that is always consumed varies, but there is a margin for the amount of air supplied (oxygen amount). The air ratio is set to exceed 1.0. Therefore, a slight increase in the amount of waste supply does not lead to the generation of new carbon monoxide due to the consumption of excess air, but if more waste is input, it will lead to the generation of carbon monoxide.

  In this way, because it is difficult to homogenize and quantitatively put in waste, the oxygen concentration fluctuates and changes in a complex manner. By changing the oxygen concentration, which changes drastically in time series, to a fractal dimension, the time series changes The complexity is converted into a numerical value, that is, a monotonous change is converted into a low numerical value, and a complicated change is converted into a high numerical value. The fractal dimension representing this complexity changes more slowly than the original time-series oxygen concentration data, and when control is performed based on this, the control parameter change frequency (correction frequency) is higher than in the past. Can be reduced, leading to stable combustion control. In addition, because it is a numerical value based on the complexity of oxygen consumption over time, the number of data to change to a fractal dimension numerical value is set to a number within a predetermined time that is not too long, so that oxygen shortage can be quickly solved. And it can be predicted as accurately as possible. The predetermined time that is not too long can be, for example, within a period of time until the waste due to some dropping is sufficiently combusted, and can be a time when the average amount of waste is sufficiently combusted. However, it is natural that the lower limit is the minimum number of data required to obtain the fractal dimension.

  In the above embodiment, when the fractal dimension exceeds a predetermined value, the parameter determination unit 37 corrects the primary and secondary air supply amounts and the waste supply amount output from the fuzzy calculation unit 34. In addition, it has been described that the output is changed. For example, when the fractal dimension exceeds a predetermined value, predetermined primary and secondary air supply amounts and dust supply amounts are output from the fuzzy calculation unit 34. Instead of this, it may be output from the parameter determination unit 37.

  In the above embodiment, the combustion control is performed by adjusting the amount of secondary air. However, for example, the amount of oxygen supplied into the incinerator is adjusted instead of the secondary air. May be.

  In the above embodiment, the case where the furnace for reducing the volume and the volume of the object to be reduced is a fluidized bed incinerator has been described. In this case, a stoker furnace, kiln furnace, etc. may be used. Even in this case, the oxygen concentration is measured at a portion of the freeboard on the burning garbage and before the secondary air is supplied, and the operation control device described above is used. The waste supply amount, the primary and secondary air supply amounts may be controlled using the above configuration.

  Further, the volume-reduction target may be ash and the furnace may be a melting furnace. In this case, the fluidized bed incinerator according to the above embodiment is measured by an oxygen concentration meter that measures the oxygen concentration in the space above the molten slag. As described above, the fractal dimension is obtained, and the secondary air supply amount is adjusted based on the fractal dimension, whereby stable melting control (operation) can be performed.

It is a figure which shows schematic structure of the waste incineration equipment which concerns on embodiment of this invention. It is a principal part side view of the refuse supply apparatus in the refuse incineration 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 incineration equipment. It is a block diagram which shows schematic structure of the fractal dimension calculating part in the same operation control apparatus. 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 which shows the oxygen concentration, the fractal dimension, and the carbon monoxide concentration in the same waste incineration facility. It is a graph which shows the oxygen concentration, the flapper opening degree, and the carbon monoxide concentration in the incinerator according to the conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fluidized bed incinerator 3 Garbage supply apparatus 5 Secondary air supply apparatus 6 Oxygen concentration meter 8 Carbon monoxide concentration meter 9 Operation control apparatus 12 Screw blade 13 for conveying a waste 13 Electric motor 14 Waste amount detection member 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 35 Storage unit 36 Fractal dimension calculation unit 37 Parameter determination unit 41 Waste supply amount calculation unit 42 Secondary air reference Quantity calculation unit 43 Secondary air correction amount calculation unit 44 Addition unit 51 Curve calculation unit 52 Number determination unit 53 Logarithm calculation unit 54 Dimension calculation unit

Claims (5)

A furnace for reducing the volume by applying heat to the volume reduction treatment object, a treatment object supply means for supplying the volume reduction treatment object to the furnace, an oxygen concentration meter for measuring the oxygen concentration in the furnace, A volume reduction facility having an operation control device for performing a volume reduction operation of the furnace based on the detected oxygen concentration,
The operation control device includes a storage unit for storing the oxygen concentration measured by the oximeter in time series, and a fractal dimension calculation for obtaining a fractal dimension of an oxygen concentration curve obtained from the stored time series oxygen concentration data. And a parameter determination unit for determining a control parameter for volume reduction operation based on the fractal dimension obtained by the fractal dimension calculation unit.   The volume reduction equipment according to claim 1, wherein the furnace is a waste incinerator, and the control parameter is at least an air amount or an oxygen amount to be supplied into the waste incinerator.   The volume reduction equipment according to claim 1, wherein the furnace is a melting furnace, and the control parameter is at least an air amount or an oxygen amount supplied into the melting furnace. Reducing the volume of the furnace based on the oxygen concentration measured by the oxygen concentration meter installed in the furnace of the volume reduction facility that supplies the heat to the furnace by the treatment object supply means and reduces the volume by supplying heat. An operation control device for performing a continuous operation,
A storage unit that stores the oxygen concentration measured by the oximeter in time series, a fractal dimension calculation unit that calculates a fractal dimension of an oxygen concentration curve obtained from the stored time-series oxygen concentration data, and the fractal dimension An operation control apparatus in a volume reduction facility comprising a parameter determination unit that determines at least a supply amount of a processing object among control parameters for volume reduction operation based on a fractal dimension obtained by a calculation unit . A furnace for reducing the volume by applying heat to the volume reduction treatment object, a treatment object supply means for supplying the volume reduction treatment object to the furnace, an oxygen concentration meter for measuring the oxygen concentration in the furnace, A program for controlling the operation control apparatus in a volume reduction facility having an operation control apparatus for performing a volume reduction operation of a furnace by obtaining a fractal dimension of an oxygen concentration curve obtained from the measured time-series oxygen concentration data. There,
A data storage function for storing time-series oxygen concentration data measured by the oximeter in the storage unit, and inputting the time-series oxygen concentration data stored in the storage unit to obtain an oxygen concentration curve within a predetermined time. The curve calculation function to be obtained, the number calculation function to obtain the number of coatings of the curve with respect to various coating distances for the oxygen concentration curve obtained by this curve calculation function, the value of each coating distance and the number calculation function Corresponds to the logarithm calculation function that calculates the natural logarithm by inputting the obtained covering number, the logarithmic value of the covering distance obtained by this logarithmic calculation function, and the slope of the regression line obtained from the logarithmic value of the covering number An operation control program comprising a dimension calculation function for obtaining a fractal dimension to be performed.

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