JPH04316914A - Co control method in incinerator - Google Patents

Abstract

PURPOSE:To control an amount of air in a secondary combustion chamber promptly and properly without any time lag and inhibit the generation of dioxin or the like by detecting in real time the CO concentration in the secondary combustion chamber based on at least one of the two factors, say, the brightness and chromaticity of the secondary combustion chamber. CONSTITUTION:Combustion air is supplied to a combustion chamber 3 in an incinerator 1 from a combustion air blower by way of a ventilation duct 5 and the refuse on a combustion zone 2 is incinerated whereas combustion exhaust gas 16 rises to a secondary combustion chamber 4. Then, second combustion is carried out by a secondary air 17 supplied to the secondary chamber 4 from a secondary air blower by way of a secondary ventilation duct 8. In this case, the inside of the secondary combustion chamber 4 is photographed by means of an industrial TV camera 12. The photographed image information is image-processed by an image processing device 13 where at least one of the brightness and chromaticity in the secondary combustion chamber is detected as a numerical data. After collating the numerical date with correlation data and deciding the CO concentration, a control device 14 controls the amount of secondary air.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CO control method in an incinerator for suppressing the generation of dioxins in a municipal waste incinerator or a waste incinerator.

0002

BACKGROUND OF THE INVENTION In recent years, environmental pollution due to dioxins generated from municipal waste incinerators and waste incinerators has become a problem. In order to suppress dioxins in an incinerator, the following factors are important.

[0003]■. Maintain high combustion gas temperature. ■． Ensure a sufficiently long residence time of combustion gas in the high temperature range. ■． Good mixing of unburned gas and air in combustion gas.

[0004] However, direct analysis of dioxins requires expensive analytical equipment and advanced techniques, and is not suitable for continuous analysis. To this end, it has been considered to monitor carbon monoxide (CO), which is a representative indicator of unburned gas and has a strong correlation with dioxins.

[0005] Conventionally, CO was stored in the middle of the flue of an incinerator.
The CO concentration of the combustion exhaust gas is measured using a CO meter, and the combustion state of the incinerator is adjusted by feedback control such as adjusting the amount of combustion air based on the measured value.
It was under O control.

[0006]

However, in the conventional configuration described above, there is a time delay in detecting the CO concentration, so the amount of combustion air is increased in accordance with the increase in the CO concentration detected by the CO meter. If the amount of combustion air is maintained until the CO meter detects an appropriate value for the CO concentration, there is a problem in that the amount of combustion air becomes excessive in the incinerator, and the excess oxygen promotes the production of dioxins.

[0007] The present invention solves the above problems, and
It is an object of the present invention to provide a method for controlling CO in an incinerator, which can adjust the concentration in real time to maintain an appropriate oxygen concentration range in the incinerator and suppress the production of dioxins.

[0008]

[Means for Solving the Problems] In order to solve the above problems, the CO control method of the present invention images the inside of the secondary combustion chamber of an incinerator with an industrial television camera, and transmits the image information to an image processing device. Image processing is performed to detect the brightness in the secondary combustion chamber as numerical data, and this numerical data is obtained empirically in advance to create CO in the secondary combustion chamber.
The C on the correlation data corresponding to the numerical data is checked against the correlation data representing the correlation between the concentration and the numerical data.
The O concentration is recognized as the current CO concentration in the secondary combustion chamber, and the amount of air supplied to the secondary combustion chamber is adjusted based on this CO concentration.

[0009]

[Operation] With the above configuration, the CO concentration in the secondary combustion chamber is recognized by at least one of the brightness and chromaticity in the secondary combustion chamber, so the current CO concentration in the secondary combustion chamber is
The concentration can be detected in real time, and the air amount can be adjusted in response to the current combustion state in the secondary combustion chamber without any time delay. This eliminates poor mixing of unburned gas and air due to insufficient air volume, decreases in combustion temperature due to excessive combustion air, and eliminates the generation of dioxins precursor substances, suppressing the generation of dioxins. be able to.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, an incinerator 1 has a combustion chamber 3 composed of multiple stages of combustion zones 2, and a secondary combustion chamber 4 formed above the combustion chamber 3. Further, a blower duct 5 is opened below each combustion stag 2, and a combustion air blower 6 and a damper device 7 are interposed at the base end side of the blower duct 5. Furthermore, a secondary air blowing duct 8 is opened in the secondary combustion chamber 4, and a secondary air blower 9 and a second damper device 10 are interposed at the base end side of the secondary air blowing duct 8. .

[0011] An industrial television camera 12 is provided outside the secondary combustion chamber 4 to take an image of the inside of the secondary combustion chamber 4 through a viewing window 11 formed on the wall surface. This industrial television camera 12 is connected to an image processing device 13 via a signal line, and the image processing device 13 is connected to a control device 14. The control device 14 also includes a combustion blower 6, a damper device 7, a secondary air blower 9, and a second damper device 10.
are connected.

[0012] The operation of the above configuration will be explained below. Combustion air 15 is supplied to the combustion chamber 3 from a combustion air blower 6 through a ventilation duct 5, and the garbage on the combustion zone 2 is incinerated by receiving the combustion air 15. Further, the combustion exhaust gas 16 rises from the combustion chamber 3 to the secondary combustion chamber 4, passes through the secondary air blowing duct 8 from the secondary blower 9, receives the secondary air 17 supplied to the secondary combustion chamber 4, and then enters the secondary combustion chamber 4. Next combustion.

[0013] Then, the interior of the secondary combustion chamber 4 is imaged with an industrial television camera 12, and the image information is image-processed in the image processing device 13 to determine at least one of the brightness and chromaticity in the secondary combustion chamber 4. Detected as numerical data. As the numerical data representing this brightness, units of illumination such as luminous intensity, illuminance, and luminance are used in combination.

Furthermore, the detected numerical data is checked against correlation data that has been empirically obtained and created in advance and represents the correlation between the CO concentration and the numerical data. This correlation data is obtained by empirically determining the correlation by experimentally detecting numerical data and measuring the CO concentration in the secondary combustion chamber 4 by a separate means such as a CO meter.

[0015] Then, by checking with the correlation data, the CO concentration on the correlation data corresponding to the numerical data is recognized as the current CO concentration in the secondary combustion chamber 4, and that value is input to the control device 14 as a combustion index. . In response to this input, the control device 14 calculates the excess or deficiency of the air amount for the current CO concentration, and uses the combustion blower 6, damper device 7, secondary air blower 9, and second air blower to adjust the calculated air amount. A control instruction signal is sent to the damper device 10 to adjust the amount of combustion air supplied to the combustion chamber 3 and the amount of secondary air supplied to the secondary combustion chamber 4.

Therefore, since the CO concentration in the secondary combustion chamber 4 is recognized by at least one of the brightness and chromaticity in the secondary combustion chamber 4, the current
The CO concentration in the secondary combustion chamber 4 can be detected in real time, and the combustion air amount and secondary air amount can be adjusted in immediate response to the current combustion state in the secondary combustion chamber 4 without any time delay.

[0017] This eliminates poor mixing of unburned gas and air due to insufficient air volume, lowering of the combustion temperature in the furnace due to excessive air volume, and the generation of dioxins precursor substances. generation can be suppressed.

[0018]

As described above, according to the present invention, the CO concentration in the secondary combustion chamber can be detected in real time by at least one of the brightness and chromaticity in the secondary combustion chamber. The amount of air can be adjusted without any time delay, preventing poor mixing of unburned gas and air due to insufficient air amount, lowering of combustion temperature due to excessive combustion air, and even precursor substances of dioxins. The generation of dioxins is eliminated, and the production of dioxins can be suppressed.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an incinerator in one embodiment of the present invention.

[Explanation of symbols]

1 Incinerator 3 Combustion chamber 4 Secondary combustion chamber 12 Industrial TV camera 13 Image processing device

Claims (1)

[Claims] Claim 1: The inside of the secondary combustion chamber of the incinerator is imaged with an industrial television camera, and the captured image information is processed by an image processing device to obtain at least one of brightness and chromaticity in the secondary combustion chamber as numerical data. This numerical data is compared with correlation data representing the correlation between the CO concentration in the secondary combustion chamber and the numerical data, which has been obtained and created empirically in advance, and the correlation corresponding to the numerical data is determined. A method for controlling CO in an incinerator, characterized in that the CO concentration on the data is recognized as the current CO concentration in the secondary combustion chamber, and the amount of air supplied to the secondary combustion chamber is adjusted based on this CO concentration.