JP4138556B2 - Molten slag flow monitoring device and monitoring method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waste combustion facility, and relates to a technique for monitoring a molten slag flow state at a discharge port for discharging molten slag out of the system.
[0002]
[Prior art]
As the state detection of the molten slag in the prior art, the molten slag is directly visually monitored from the inspection viewing window provided below the molten slag discharge port (hereinafter referred to as slag tap) provided at the melting furnace outlet, In addition, the molten slag is monitored by indirect visual observation using a camera image provided in contact with the inspection window.
[0003]
Further, as a monitoring method other than visual observation, it has been proposed to photograph the molten slag flow at the outlet of the melting furnace and monitor the molten slag state based on the luminance data of the image frame obtained by the photographing (see Patent Document 1). ).
[0004]
[Patent Document 1]
JP 2000-304232 A
[0005]
[Problems to be solved by the invention]
However, in the above-described prior art, in direct visual inspection of the molten slag and indirect visual inspection with a camera, there is a problem that it is necessary to constantly monitor and a fully automatic operation cannot be performed.
[0006]
Moreover, although the technique of patent document 1 in a prior art uses the brightness | luminance of molten slag as the reference | standard of determination, in an actual molten combustion facility, a molten molten slag and the combustion flame of pyrolysis gas are mixed in the molten slag flow lower part. . Further, since an auxiliary fuel burner such as kerosene or natural gas is used depending on the melt combustion conditions, the burner flame may also exist.
[0007]
These combustion gas flames and burner flames have the same brightness as the molten slag, and cannot be detected separately from the combustion gas flames and burner flames by the monitoring method that distinguishes the molten slag flow based on the brightness as in the prior art. There was a problem.
[0008]
For example, even when the molten slag flow is discontinuous or stopped, the flame of the high-temperature combustion gas in the furnace blown out from the slag tap is detected, so that deterioration of the molten slag flow cannot be determined. In addition, a burner flame with auxiliary fuel is used as the molten slag flow deteriorates, but at this time, the brightness of the burner flame blown from the slag tap is detected in the prior art, so it was judged that the molten slag flow was improved. Can not.
[0009]
An object of the present invention is to provide a monitoring apparatus and method that can always automatically and stably detect a molten slag flowing state even when a combustion gas flame or a burner flame is present in addition to molten slag at a slag discharge port. It is in.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, the present invention mainly adopts the following configuration.
In a melting combustion furnace provided with a discharge port for separating molten slag generated in a melting combustion furnace from combustion gas and discharging it out of the melting combustion furnace under gravity flow, and an auxiliary combustion facility provided in the vicinity of the discharge port,
Capture image data including molten slag flowing down from the outlet,
Measure the brightness, color and hue of the image data,
Wherein comparing the respective values of the measured luminance and color hue, brightness, provided in each of the color and hue, and a distinct threshold and a combustion gas flame and an auxiliary fuel burner flame and the molten slag,
In the comparison, the molten slag and the combustion gas flame are distinguished by a color threshold, and the molten slag and the auxiliary combustion burner flame are distinguished by a hue threshold,
The distinction result is extracted, and the extracted image is recognized as a molten slag.
[0011]
In the molten slag flow monitoring device, the image data recognized as the molten slag is converted into an area, and the flow state of the molten slag is determined based on the converted area value.
[0012]
By adopting such a configuration, the present invention can always automatically and stably detect the molten slag flowing state even in the presence of a combustion gas flame or a burner flame in addition to the molten slag at the slag discharge port. .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
A molten slag monitoring device and a monitoring method according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing an overall configuration of a monitoring apparatus for molten slag according to an embodiment of the present invention, and FIG. 2 is a flowchart showing a method for checking a flowing state of molten slag according to the present embodiment. FIG. 3 is a diagram showing the relationship between the combustion gas temperature and the luminance, and FIG. 4 is a diagram showing the relationship between the combustion gas flame, the molten slag and the natural gas flame, and the hue and color.
[0014]
Here, 1 is a swirl melting furnace, 2 is a swirl melting furnace outlet chamber, 3 is a slag discharge port, 4 is a secondary combustion chamber, 5 is a chute, 6 is a monitoring camera, 7 is a personal computer, 8 is an image processing board, Reference numeral 9 denotes a personal computer main body, and 10 denotes image processing software.
[0015]
In FIG. 1, a molten slag discharge port (slag tap) 3 is disposed at the lower part of the outlet chamber 2 of the swirl melting furnace 1, and after the molten slag and combustion gas are separated in the swirl melting furnace outlet chamber 2, the combustion gas is Completely combusted in the secondary combustion chamber 4, the molten slag flows down from the slag tap 3 and is introduced into the granulation tank through the chute 5. Note that the upstream and downstream devices of the swirl melting furnace 1 include a gasification furnace that supplies pyrolysis gas to the swirl melting furnace 1, ventilation equipment that supplies combustion air, and discharge from the secondary combustion chamber 4. An exhaust gas treatment facility for the combustion gas and a chimney are installed, which are omitted in FIG.
[0016]
The molten slag monitoring device according to the embodiment of the present invention includes a monitoring camera 6 attached to a chute portion 5 below the slag tap 3 and a personal computer 7 that performs image processing of signals from the monitoring camera 6.
[0017]
From various tests in the combustion test furnace, the following results could be obtained for each relationship of the molten slag, the combustion gas flame, and the auxiliary fuel burner flame. First, regarding luminance, it has been confirmed that “luminance” that quantitatively represents the degree of brightness has a correlation with temperature. FIG. 3 schematically shows the relationship between “luminance” and temperature. According to FIG. 3, the “brightness” increases as the temperature increases, so the molten slag has a predetermined brightness. However, even if it is not a molten slag, the auxiliary fuel burner flame and the combustion gas flame also have luminance depending on the temperature, so it is not possible to distinguish between the molten slag and the auxiliary fuel burner flame or the combustion gas flame only by “luminance”. .
[0018]
On the other hand, even if the temperature conditions are the same, it has been found that the “color” representing the degree of vividness and the “hue” representing the hue are different for solids, gases and liquids. FIG. 4 schematically shows hues and color ranges of the molten slag, the combustion gas flame, and the auxiliary fuel burner flame at the same temperature.
[0019]
In FIG. 4, the “color” of the combustion gas flame is lower than that of the molten slag. For this reason, even if the combustion gas flame has the same brightness as the molten slag, the degree of "color" differs, so only the molten slag can be detected by setting the "luminance" and "color" thresholds appropriately. It becomes possible. In other words, if the molten slag flows down instead of solidifying at the outlet, the predetermined luminance can be secured by the molten slag, and even if the combustion gas flame exists near the outlet, the color of the molten slag Since the degree is different from the molten slag, the molten slag can be distinguished from the combustion gas flame by setting a threshold value.
[0020]
Furthermore, when the auxiliary fuel is a natural gas burner or an oxygen burner, the hue of the molten slag is reddish yellow, whereas the natural gas flame exhibits a blue hue, so the “hue” is different. Therefore, it is possible to distinguish between the molten slag and the auxiliary fuel burner flame based on the threshold values of “luminance” and “hue”, and it is possible to determine that the slag is molten. Here, the auxiliary fuel is not always used, but is used when necessary. Therefore, the use timing signal is used to distinguish between the molten slag and the auxiliary fuel burner flame. it can. That is, the distinction between the molten slag and the combustion gas flame is a color (the colors are partially overlapped, but can be distinguished by setting the threshold strictly), and the distinction between the molten slag and the auxiliary fuel burner flame Is a hue (cannot be distinguished by color), it is only necessary to use the timing signal to determine whether the parameter for discrimination is a color or a hue. Further, the three types of “luminance”, “hue”, and “color” may be used to distinguish the molten slag from the combustion gas flame and / or the auxiliary fuel burner flame.
[0021]
As described above, in the embodiment of the present invention, only the molten slag is detected by using the difference in numerical values of “brightness”, “color”, and “hue” in the molten slag, the combustion gas flame, and the auxiliary fuel burner flame. In addition, by measuring the “brightness”, “color”, and “hue” of the target object and recognizing only the data that falls within the prescribed threshold value as molten slag, only molten slag can be reliably obtained under any combustion conditions. It becomes possible to measure.
[0022]
FIG. 2 shows a processing flow in the personal computer 7 of the image data photographed by the monitoring camera 6. Image data captured by the monitoring camera 6 is taken into the image memory of the image processing board 8 (step 1). Next, portions corresponding to “luminance”, “color”, and “hue” that fall within the specified threshold are extracted from the captured image memory (step 2). Specifically, it has a luminance indicating that the slag is not solidified but melted, has a color that can be distinguished from the combustion gas flame, and an auxiliary fuel burner flame (eg, natural gas flame) An image having a hue that can be distinguished, that is, an image of the molten slag is extracted and the image taken by the monitoring camera 6 is superimposed and output (step 3). By comparing this extracted image with the actual captured image, the distinguished ability can be confirmed. Subsequently, the area of the extracted image (image corresponding to the molten slag) is calculated (step 4), and the area average value within a predetermined time is compared with a preset threshold value, and the slag flow state is determined. Determine (step 5).
[0023]
By setting the image area for data extraction in the vicinity of the slag tap opening, it is possible to detect blockage of the opening when the calculated area value is equal to or smaller than a predetermined value.
[0024]
By setting the image area as a molten slag dripping area, it is possible to detect a molten slag flow failure when the calculated area value is equal to or less than a predetermined value.
[0025]
As described above, the feature of the present invention is that “luminance”, “color”, and “hue” are detected from the molten slag flow image, and only data in which each measured value satisfies a predetermined threshold is regarded as the molten slag flow. recognize. Furthermore, it is possible to calculate the area of the recognized molten slag flow (data) and determine the molten slag flow state from the numerical value of the area.
[0026]
In addition, since the molten slag detection unit in the molten slag flow image is digitally processed by a personal computer, any multiple areas of one image can be set as the detection area. Two locations of the molten slag dripping section can be monitored simultaneously.
[0027]
【The invention's effect】
According to the present invention, at the slag discharge port and the chute portion, even when a combustion gas flame or an auxiliary fuel burner flame is present in addition to the molten slag, the molten slag flow state is always stably monitored without monitoring. It can be detected.
[0028]
By detecting the slag flow state, it is possible to prevent clogging due to slag solidification at the slag discharge port.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a molten slag monitoring device according to an embodiment of the present invention.
FIG. 2 is a flowchart showing a method for checking a flowing-down state of molten slag according to the present embodiment.
FIG. 3 is a graph showing a relationship between combustion gas temperature and luminance.
FIG. 4 is a diagram showing the relationship between a combustion gas flame, molten slag, and a natural gas flame, and hue and color.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Swivel melting furnace 2 Swivel melting furnace exit chamber 3 Slag discharge port 4 Secondary combustion chamber 5 Chute part 6 Monitoring camera 7 Personal computer 8 Image processing board 9 Personal computer body 10 Image processing software

Claims (4)

In a melting combustion furnace provided with a discharge port for separating molten slag generated in a melting combustion furnace from combustion gas and discharging it out of the melting combustion furnace under gravity flow, and an auxiliary combustion facility provided in the vicinity of the discharge port,
Capture image data including molten slag flowing down from the outlet,
Measure the brightness, color and hue of the image data,
Wherein comparing the respective values of the measured luminance and color hue, brightness, provided in each of the color and hue, and a distinct threshold and a combustion gas flame and an auxiliary fuel burner flame and the molten slag,
In the comparison, the molten slag and the combustion gas flame are distinguished by a color threshold, and the molten slag and the auxiliary combustion burner flame are distinguished by a hue threshold,
A molten slag flow monitoring apparatus that extracts an image of the distinguished result and recognizes the extracted image as a molten slag. In claim 1,
The molten slag flow monitoring apparatus, wherein the image data recognized as the molten slag is converted into an area, and the flow state of the molten slag is determined based on the converted area value. In claim 2,
A molten slag flow monitoring device that detects slag blockage at the discharge port based on the area value by capturing image data in the vicinity of the discharge port. A method for monitoring the flow of molten slag in a molten combustion furnace comprising a discharge port for discharging molten slag by gravity flow, and an auxiliary combustion facility provided in the vicinity of the discharge port,
Capturing image data including molten slag flowing down from the outlet;
Measuring the brightness, color and hue of the image data;
The step of comparing the respective values of brightness and color hue was the measured luminance was provided in each of the color and hue, and said distinguishable to the molten slag and combustion gas flame and an auxiliary fuel burner flame threshold When,
In the comparison, the molten slag and the combustion gas flame are distinguished by a color threshold, and the molten slag and the auxiliary combustion burner flame are distinguished by a hue threshold;
A step of extracting images of the distinguished results, and recognizing the extracted images as molten slags.

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