JP2020165626A - Method for operating combustion equipment - Google Patents

Abstract

To provide new means for controlling the emission of CO in combustion equipment.SOLUTION: There is provided a method for operating combustion equipment which comprises a kiln 80, a stoker 50, a secondary combustion chamber 70, a smoke exhaust portion 20, an imaging unit 60, a data processing unit 30, a CO measurement unit 10, and a control unit 40. The method includes a step in which the data processing unit analyzes the luminance of flame on the basis of an image of the flame of an outlet portion in the kiln captured by the imaging unit, a step in which the CO measurement unit measures a CO amount in the smoke exhaust portion, a step in which the data processing unit analyzes a correlation between the CO amount and the luminance of the flame, and a step in which the control unit controls a combustion state in the kiln on the basis of at least the correlation and the luminance of the flame.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method of operating a combustion facility. More specifically, it relates to a method of operating a combustion facility equipped with a kiln.

Combustion furnaces are often used to dispose of waste. In combustion equipment including a combustion furnace, it is necessary to pay attention to exhaust gas components, and in particular, it is necessary to pay attention to CO emissions. Patent Document 1 discloses that oil is completely removed by heating from recycled raw materials such as Dalai powder and dead copper to which oil is attached. As a result, the smelting furnace can be safely treated without causing damage to the equipment, and the exhaust gas is also exhausted in a clean state to disclose an environment-friendly pretreatment method for recycled raw materials. Has been done.

Patent Document 2 discloses a CO control method in an incinerator for suppressing the generation of dioxins in an urban waste incinerator and a waste incinerator. Further, in Patent Document 2, the secondary combustion chamber of the incinerator is imaged with an industrial television camera, and the captured image information is image-processed by an image processing device to quantify at least one of the brightness and the chromaticity in the secondary combustion chamber. Detection is disclosed as data. Then, it is disclosed that the correlation data representing the correlation between the CO concentration and the numerical data in the secondary combustion chamber is used.

Patent Document 3 discloses that the burnout point is appropriately controlled. Further, Patent Document 3 discloses that a camera for photographing the inside of the rotary stalker is provided in order to optically detect the burnout point.

Patent Document 4 discloses that in a waste incinerator, the inside of the incinerator is captured by an industrial TV, and the average brightness level of the flame in the dry zone with respect to the brightness level of the entire image is obtained by image processing. Then, it discloses that the amount of operation such as combustion air and stoker speed is adjusted according to the change.

Japanese Unexamined Patent Publication No. 2015-067871 Japanese Patent No. 2690208 Japanese Patent Application Laid-Open No. 2-187510 Japanese Unexamined Patent Publication No. 1-49818

In controlling the amount of CO, it is important how much CO is contained in the gas actually emitted. Even if the CO amount is monitored in the process of reaching the smoke exhaust part (for example, the relatively previous process of the combustion equipment), there is a possibility that the CO amount of the gas actually discharged in the smoke exhaust part may deviate from the CO amount. There is.

However, when a CO measurement sensor is provided in the smoke exhaust unit in order to monitor the CO amount of the emitted gas, a new problem arises. For example, even if the CO measurement sensor of the smoke exhaust unit warns that the amount of CO has increased, if the combustion equipment is adjusted after receiving the warning, a time lag will occur. That is, it takes time for the adjustment result of the combustion equipment to be reflected in the CO measurement sensor of the smoke exhaust unit. During that time, the increased amount of CO will be discharged together with the smoke.

For the above reasons, it is an object of the present disclosure to provide a new means for controlling CO emissions in a combustion facility.

As a result of diligent studies by the present inventors, it has been found that when the amount of CO in the smoke exhaust part increases, there is a specific sign in the time zone before that. More specifically, we found that there was a change in the state of the flame at the exit of the kiln.

An invention completed based on the above findings, in one aspect, includes the following inventions.
(Invention 1)
It is a method of operating combustion equipment,
The equipment includes a kiln, a stalker, a secondary combustion chamber, a smoke exhaust unit, an imaging unit, a data processing unit, a CO measurement unit, and a control unit.
The method is
A step of analyzing the brightness of the flame by the data processing unit based on the image of the flame at the outlet portion in the kiln captured by the imaging unit.
A step in which the CO measuring unit measures the amount of CO in the smoke exhausting unit,
A step in which the data processing unit analyzes the correlation between the amount of CO and the brightness of the flame.
A step in which the control unit controls the combustion state in the kiln based on at least the correlation and the brightness of the flame.
The method comprising.
(Invention 2)
The method of the present invention, wherein the controlled step comprises adjusting at least one of an air amount, a raw material input amount, and a fuel amount.
(Invention 3)
The method according to the method 1 or 2, wherein the controlling step controls the combustion state in the kiln based on the brightness of a part of the flame.
(Invention 4)
The method of the third invention, wherein a part of the flame is an external flame.

In one aspect, in the invention, the data processing unit analyzes the correlation between the amount of CO and the brightness of the flame, and the control unit is in the kiln based on at least the correlation and the brightness of the flame. Includes a step of controlling the combustion state of. Thereby, the amount of CO can be suppressed more effectively.

The outline of the combustion equipment in one embodiment is shown. In the combustion equipment of one embodiment, the temporal change of brightness is shown. A few minutes before the time when the amount of CO is increased, the brightness tends to decrease. In the combustion equipment of one embodiment, the temporal change of brightness is shown. A few minutes before the time when the amount of CO is increased, the brightness tends to decrease. In the combustion equipment of one embodiment, the temporal change of brightness is shown. A few minutes before the time when the amount of CO is increased, the brightness tends to decrease.

Hereinafter, specific embodiments will be described. The following description is for facilitating the understanding of the invention. That is, it is not intended to limit the scope of the present invention.

1. 1. Equipment Overview FIG. 1 shows an outline of the equipment of the present disclosure in one embodiment. The equipment includes a kiln 80, a stoker 50, a secondary combustion chamber 70, a smoke exhaust unit 20, an imaging unit 60, a data processing unit 30, a CO measuring unit 10, and a control unit 40.

A kiln is a furnace for burning waste and the like. A raw material (for example, waste) and a fuel (for example, waste oil) are used for combustion.

The stalker is for post-burning the material burned in the kiln.

The secondary combustion chamber is for completely burning various gases generated after combustion in the kiln.

The smoke exhaust section communicates with the secondary combustion chamber and exhausts exhaust gas.

The imaging unit has a structure capable of photographing the inside of the kiln, and the captured data is transmitted to the data processing unit.

The CO measuring unit measures the amount of CO contained in the gas discharged from the smoke exhausting unit. The measurement data is transmitted to the data processing unit.

The data processing unit processes the data received from the CO measuring unit and the photographing unit. For example, the data processing unit can store the data received from the CO measuring unit and the photographing unit. In addition, the data processing unit can analyze the data received from the CO measuring unit and the photographing unit (for example, correlation analysis). The data processing unit may be, for example, any information processing terminal (for example, a server, a PC, etc.). Further, the information processing terminal may be provided with desired image analysis software, statistical analysis software, or the like.

The control unit can control the combustion state of the kiln. For example, the control unit can adjust at least one of the amount of air, the amount of raw material input, and the amount of fuel. In addition, the control unit can refer to the data stored and / or generated by the data processing unit. Then, control can be performed based on the data. The control unit may be, for example, any information processing terminal (for example, a server, a PC, etc.). Further, the control unit may exist in the same hardware as the data and the processing unit, or may exist separately and independently.

The operation method using these facilities will be described below.

2. Combustion Equipment Operating Method In one embodiment, the present disclosure relates to a combustion equipment operating method. The method comprises at least the following steps.
-A process in which the data processing unit analyzes the brightness of the flame based on the image of the flame at the exit of the kiln captured by the imaging unit.
-A process in which the CO measuring unit measures the amount of CO in the smoke exhaust unit.
-A process in which the data processing unit analyzes the correlation between the amount of CO and the brightness of the flame.
-A process in which the control unit controls the combustion state in the kiln, at least based on the correlation and the brightness of the flame.
In the following, specific examples will be described in detail for each step.

2-1. Step of analyzing the brightness of the flame The image data (which may be a moving image or a still image) of the flame at the exit portion in the kiln captured by the imaging unit is transmitted to the data processing unit. The data processing unit can analyze the image data. More specifically, the brightness of the flame can be analyzed.

Flames in the kiln occur at the entrance, exit, or somewhere in between. From the viewpoint of the amount of CO emitted by the smoke exhaust part, the flame at the outlet part is the most important. Therefore, what the data processing unit analyzes is image data including at least the flame at the exit portion.

Moreover, the combustion itself occurs not only in the kiln but also in the secondary combustion chamber and the stoker. However, the combustion state in the stoker does not contribute significantly to the generation of CO. In addition, although the secondary combustion chamber has the role of completely burning the generated gas in the incomplete combustion state, even if the combustion state in the secondary combustion chamber is monitored, the generation of the gas in the incomplete combustion state itself is stopped. Does not contribute to. For this reason, it is important to analyze the flame at the exit in the kiln.

Specific analysis contents include the brightness of the flame. In one example, the luminance may be represented in grayscale in the range 0-255. Since a normal image is color, the intensity of RGB may be substituted into a conversion formula for luminance (eg "Y = 0.299R + 0.587G + 0.114B") to derive the image.

Further, in a preferred embodiment, the brightness may not be simply quantified on a gray scale, but the time change may be analyzed (for example, moving average, derivative, etc.). As a result, it is possible to detect whether the brightness tends to increase or decrease. It is possible to improve the accuracy in deriving the correlation with the amount of CO by not simply analyzing only the brightness value but also analyzing the temporal change.

Also, in a preferred embodiment, the brightness of a portion of the flame is analyzed rather than the entire flame at the outlet portion in the kiln. Since there is a bias in brightness for the entire flame, the accuracy in deriving the correlation with the amount of CO may be inferior. Therefore, it is preferable to narrow down the analysis range to an arbitrary part of the flame (for example, an external flame part or a part having a brightness of a predetermined percentage or more based on the maximum brightness).

2-2. Step of measuring CO amount In addition to the above luminance analysis, a step of measuring CO amount is carried out. The step of measuring the amount of CO may be performed in parallel with the measurement and analysis of the luminance, or may be performed before and after these.

The amount of CO is measured by the CO measuring unit at the smoke exhaust unit. The CO measuring unit is equipped with a CO sensor and transmits the measured data to the data processing unit. The CO sensor itself is not particularly limited, and a sensor known in the art can be used. Further, the CO measuring unit can measure not only the CO amount itself but also the temporal change of the CO amount and transmit it to the data processing unit as well as the brightness of the flame.

2-3. The process data processing unit that analyzes the correlation can analyze the correlation between the brightness of the flame analyzed by the above method and the amount of CO. The method for analyzing the correlation is not particularly limited. For example, the brightness of the flame and the amount of CO may be plotted and regression analysis may be performed. Further, the brightness of the flame may be a change amount rather than simply the value of the brightness itself.

In any case, by correlating the brightness of the flame with the amount of CO, it is possible to predict the amount of CO based on the brightness of the flame.

In a preferred embodiment, the correlation between the brightness of the flame at a certain time t and the amount of CO at a time t + Δt after the time t is used to make a future based on the brightness of the current flame. It is possible to predict the amount of CO in. From this point of view, in the step of analyzing the correlation, it is preferable to analyze the correlation between the brightness of the flame at a certain time t and the amount of CO at t + Δt, which is a time after the time t. The value of Δt is not particularly limited, and can be appropriately determined by comparing the temporal change in the amount of CO with the temporal change in the brightness of the flame. For example, the difference between the time when the brightness of the flame turns downward and the time when the amount of CO turns upward may be adopted (for example, Δt = 2 to 10 minutes, preferably 3 to 6 minutes). ).

2-4. Step of controlling the combustion state The control of the combustion state of the kiln is performed by the control unit. The control unit can access the data related to the correlation derived by the data processing unit using the past data. The control unit can also access the current flame brightness data analyzed by the data processing unit. Then, the control unit can predict whether or not the amount of CO increases based on the correlation and the brightness of the flame.

When the amount of CO is predicted to increase, the control unit controls the combustion state of the kiln to adjust the combustion conditions to suppress the generation of CO. The combustion condition to be adjusted includes, for example, at least one of the amount of air, the amount of raw material input, and the amount of fuel.

2-5. Automatic control method For the above-mentioned control process, the operator may operate the control unit to control the combustion state of the kiln. However, in a preferred embodiment, such a control unit may automate the step of controlling the combustion state of the kiln.

When automating, the combustion state of the kiln may be controlled according to a predetermined rule. Conditions for adjusting the combustion conditions in the direction of promoting complete combustion include, for example, that the brightness is below a predetermined value and / or that the brightness continues to decrease for a predetermined period or longer. Be done. Such a predetermined value and a predetermined period may be appropriately set in consideration of the correlation.

When automating, a program may be pre-programmed, or artificial intelligence technology (for example, an expert system, a machine learning system) may be used. For example, in the case of machine learning, the luminance data and the CO amount data may be learned, and a parameter for controlling an appropriate kiln combustion state may be output.

In equipment equipped with an exhaust chimney and a kiln, the amount of CO near the chimney was monitored. Three time zones (specifically, the following three time zones: 10:17:42-10:23:18, 11:54:44-12:01:18, and 13:26:28-13: At 29:20), it was detected that the amount of CO was increasing.

Therefore, we investigated the temporal changes in the brightness of the kiln before and after each of the three time zones. Specifically, the luminance was converted to grayscale as described above and converted to a value of 0 to 255. Then, the moving average was calculated using the converted value. The results are shown in Figures 2-4. In any case, the decreasing tendency of the brightness started 5 to 6 minutes before the increase in the amount of CO started.

From these facts, it was shown that the brightness of the flame can be utilized as data showing a sign of an increase in the amount of CO. Therefore, it was shown that by analyzing the correlation between the amount of CO and the brightness of the flame, it is possible to control the emission of CO in the combustion equipment more efficiently.

The specific embodiments of the present invention have been described above. The above embodiment is merely a specific example of the present invention, and the present invention is not limited to the above embodiment. For example, the technical features disclosed in one of the above embodiments can be applied to other embodiments. Further, unless otherwise specified, for a specific method, it is possible to replace some steps with the order of other steps, and an additional step may be added between the two specific steps. The scope of the present invention is defined by the claims.

10 CO measurement unit 20 Smoke exhaust unit 30 Data processing unit 40 Control unit 50 Stalker 60 Imaging unit 70 Secondary combustion chamber 80 Kiln

Claims (4)

It is a method of operating combustion equipment,
The equipment includes a kiln, a stalker, a secondary combustion chamber, a smoke exhaust unit, an imaging unit, a data processing unit, a CO measurement unit, and a control unit.
The method is
A step of analyzing the brightness of the flame by the data processing unit based on the image of the flame at the outlet portion in the kiln captured by the imaging unit.
A step in which the CO measuring unit measures the amount of CO in the smoke exhausting unit, and
A step in which the data processing unit analyzes the correlation between the amount of CO and the brightness of the flame.
A step in which the control unit controls the combustion state in the kiln based on at least the correlation and the brightness of the flame.
The method comprising. The method according to claim 1, wherein the controlled step includes adjusting at least one of an air amount, a raw material input amount, and a fuel amount. The method according to claim 1 or 2, wherein the controlling step controls the combustion state in the kiln based on the brightness of a part of the flame. The method according to claim 3, wherein a part of the flame is an external flame.