KR20110114095A

KR20110114095A - System and method for remotely monitoring stack smoke

Info

Publication number: KR20110114095A
Application number: KR1020100033534A
Authority: KR
Inventors: 김배훈
Original assignee: 주식회사 영국전자
Priority date: 2010-04-12
Filing date: 2010-04-12
Publication date: 2011-10-19

Abstract

A chimney smoke monitoring system that allows you to observe and determine the amount of smoke emitted through a chimney regardless of light intensity or weather conditions.
The chimney smoke monitoring system of the present invention includes an imaging unit, an exhaust gas sensor, a local data processing device, and a remote monitoring device. The imaging unit includes an optical camera for acquiring an optical image of the smoke discharged through the chimney top, and a thermal camera for acquiring a thermal image of the smoke. The exhaust gas sensor is installed at the top of the chimney to measure the amount of exhaust gas. The local data processing apparatus multiplexes the optical image and the thermal image, and transmits the multiplexed video signal to the remote monitoring apparatus. The remote monitoring apparatus receives a multiplexed video signal, formats an optical image and a thermal image, and configures one output image to display on the display unit.

Description

System and Method for Remotely Monitoring Stack Smoke}

The present invention relates to a surveillance system, and more particularly, to a surveillance system of a closed circuit television (CCTV) system. In addition, the present invention relates to a remote monitoring method using such a monitoring system.

Most of the production plants, including steel mills, and the sites that use fuels, such as waste incinerators and cogeneration plants, are equipped with large stacks. Such a chimney discharges air to the outside by natural convection, thereby discharging pollutants and non-contaminants, and releasing heat.

It is desirable that the amount of smoke emitted through the chimney remains steady without abrupt fluctuations. If the amount of smoke rises sharply, the amount of emissions regulated by the Atmospheric Environmental Conservation Act may exceed the allowable level, or at least cause misunderstandings that increased pollutant emissions have occurred to nearby residents. On the other hand, if the amount of smoke suddenly decreases, foreign matter may accumulate in the inner wall of the chimney or the heat recovery heat pipe, and the chimney may be partially blocked, or a failure may occur in a furnace or other mechanical device in front of the chimney.

Therefore, it is necessary to continuously monitor the amount of smoke emitted through the chimney at the site where the chimney is installed. Although the monitoring of the amount of smoke may be performed with the naked eye, such visual monitoring is difficult to carry out continuously. Therefore, recently, a surveillance CCTV camera is installed near the chimney outer wall or the chimney, and a system for monitoring the amount of smoke by using an image obtained through the camera is also used.

However, according to the existing chimney smoke monitoring system, it is difficult to monitor the amount of smoke as well as whether the smoke is discharged because the smoke is not properly displayed in the image at night or in the fog when the light is low. In addition, according to the existing system, because the subjective criteria for the normal range of the smoke generation amount for each worker is difficult to uniformly determine whether the abnormality, there is a problem that only a skilled person can perform the monitoring work.

The present invention is to solve such a problem, it is possible to observe and determine the amount of smoke discharged through the chimney regardless of illumination or weather conditions, and to provide a smoke smoke monitoring system that can continuously monitor the amount of smoke generated It is the technical problem to provide.

In addition, another object of the present invention is to provide a chimney smoke monitoring method capable of continuously monitoring the amount of smoke generation regardless of illuminance, weather conditions, or workers.

The chimney smoke monitoring system of the present invention for achieving the above technical problem comprises an imaging unit, an exhaust gas sensor, a local data processing device, and a remote monitoring device. The imaging unit includes an optical camera for acquiring an optical image of the smoke discharged through the chimney top, and a thermal camera for acquiring a thermal image of the smoke. The exhaust gas sensor is installed at the upper end of the chimney to measure the amount of exhaust gas. The local data processing apparatus multiplexes the optical image and the thermal image, and transmits the multiplexed video signal to the remote monitoring apparatus. The remote monitoring apparatus receives a multiplexed video signal, formats an optical image and a thermal image, and configures one output image to display on the display unit.

In the present specification, including the claims, the term "optical image" is used to refer to an image captured by a conventional image sensor using light in a visible or near infrared region collected by a condenser lens. In addition, the term "thermal image" refers to a thermal image obtained by detecting a radiation energy or temperature difference of a far-infrared region (8-12 μm) or a shorter wavelength region emitted from subjects within a viewing angle and converting the image into an electrical signal. Used as.

In a preferred embodiment, the remote monitoring device receives exhaust gas amount data from a local data processing device and includes the exhaust gas amount data in the output image for display with an optical image and a thermal image.

In a preferred embodiment, the remote monitoring device includes a smoke amount calculator and an alarm generator to generate an alarm when an abnormal state of the smoke amount is shown. The smoke amount generator calculates a smoke amount using an optical image and / or a thermal image, and the alarm generator generates an alarm visually or acoustically when the calculated smoke amount is out of a predetermined reference range.

In one embodiment, the smoke amount calculator calculates a separate smoke amount based on the optical image and the thermal image, respectively, and the alarm generator generates an alarm even when the difference between the two smoke amount values is greater than a predetermined reference value. In this case, the remote monitoring apparatus may transmit the control signal to the local data processing apparatus when the difference in the smoke amount calculation value is larger than the predetermined reference value so that the imaging unit is reset.

On the other hand, in the chimney smoke monitoring method of the present invention for achieving the above another technical problem, after acquiring the optical image and the thermal image of the smoke emitted through the chimney, and configured the optical image and the thermal image to configure one output image To display. In this state, the amount of smoke is calculated using the optical image and / or the thermal image, and when the amount of smoke is out of a predetermined reference range, an alarm is visually or audibly generated.

In a preferred embodiment, the smoke amount is calculated based on the pixel values of the plurality of pixels belonging to the smoke portion and the background portion. That is, in calculating the amount of smoke, the contour of the smoke portion is first detected in the image used for calculating the amount of smoke. Then, an area of a predetermined size is set in the outline, an average value of pixel values for pixels in the set area is calculated, and an average value of pixel values for a predetermined number of pixels outside the outline is calculated. Finally, the smoke amount is determined based on the difference between the pixel value average values.

As described above, the smoke monitoring system according to the present invention photographs the smoke emitted from the chimney by the optical camera and the thermal camera, and displays the optically captured image and the thermal image on one monitor. The thermal image indicates smoke emitted through the chimney regardless of the light level, allowing the operator to confirm the smoke release regardless of time of day or weather. On the other hand, the optically captured images are displayed in the form of color images that are familiar in everyday life, so that the operator can intuitively determine the facts and the amount of emissions. Therefore, by combining the optically captured image and the thermal image, the disadvantages of each image is compensated for, so that the worker can determine the fact and the emission of smoke regardless of the time of day or the weather.

In particular, according to a preferred embodiment, since the remote monitoring device determines the emission of smoke from the optically captured image and / or thermal image to inform the operator or manager, the operator or manager promptly responds to an abnormal situation in accordance with environmental pollution or equipment failure It helps to minimize damage.

Furthermore, according to a preferred embodiment, since the results of gas analysis in the exhaust smoke together with the optically captured image and the thermal image are displayed on one monitor, the pollutant emission situation can be comprehensively monitored.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. In the drawings,
1 is a view showing the overall configuration of an embodiment of a chimney smoke monitoring system according to the present invention;
2 is a block diagram of one embodiment of a local data processing apparatus;
3 is a block diagram of one embodiment of a remote monitoring apparatus;
4 is a flow chart showing operation of the chimney smoke monitoring system shown in FIG.
5 is a diagram illustrating an embodiment of an output image displayed through a display unit;
FIG. 6 is a flowchart showing an embodiment of a smoke amount estimating process illustrated in FIG. 4;
7 is a view showing the overall configuration of another embodiment of the chimney smoke monitoring system according to the present invention; And
8 and 9 are views showing a light shield plate installed on the top of the chimney in another embodiment of the chimney monitoring system according to the present invention.

Referring to Figure 1, the chimney smoke monitoring system according to a preferred embodiment of the present invention is installed in the camera unit 10 installed on the outer wall of the chimney 2, the upper end of the chimney 2 or the upper inner peripheral surface of the chimney discharge Gas sensor 20, a local data processing device 30 for processing the image captured by the camera unit 10 and the detection value of the exhaust gas sensor 20, and for analyzing and monitoring the image and the exhaust gas measurement values Remote monitoring device 50 is included.

The camera unit 10 includes an optical camera 10a for acquiring an optical image of smoke emitted through the top of the chimney 2 and a thermal camera 10b for acquiring a thermal image of the smoke. The exhaust gas sensor 20 measures the flow rate and temperature of the pollutant gas (eg, dust, NOx, SOx, CO, HCl, HF, NH3, CO, etc.) and the exhaust gas included in the smoke.

The local data processing apparatus 30 is installed near the chimney 2, and multiplexes an optical image and a thermal image captured by the camera unit 10, and transmits the multiplexed image signal to the remote monitoring apparatus 50. In addition, the local data processing device 30 receives the measurement signal of the exhaust gas sensor 20, processes it, analyzes it, and transmits the analyzed data to the remote monitoring device 50.

The remote monitoring apparatus 50 receives the multiplexed video signal, formats an optical image and a thermal image, and configures one output image to display on the display unit. In addition, the remote monitoring device 50 receives the gas analysis data and displays the gas analysis data on the display unit together with the optical image and the thermal image. In addition, the remote monitoring apparatus 50 transmits a control signal for remotely controlling the local data processing apparatus 30. The transmission of the video signal from the local data processing device 30 to the remote monitoring device 50 can be made via coaxial cable, for example. On the other hand, gas analysis data transmission from the local data processing device 30 to the remote monitoring device 50 and control signal transmission from the remote monitoring device 50 to the local data processing device 30 are performed through separate signal lines, for example, RS-. It may be done in a manner compliant with the 232C or RS-485 standard.

FIG. 2 is a block diagram of an embodiment of the local data processing apparatus 30 shown in FIG. 1, and the camera unit 10 and the exhaust gas sensor 20 are shown together for convenience of description. The local data processing device 30 may include analog / digital converters 32 and 34, frame buffers 36 and 38, a multiplexer 40, a gas analyzer 42, a controller 44, and an interface port 46. Equipped.

In the camera unit 10, the optical camera 10a is for acquiring an optical image of the smoke emitted through the top of the chimney (2), and the image in the visible light region in a certain color or more in a certain illumination, Below a certain illuminance, the infrared blocking function is removed to operate in black and white mode. Therefore, the optical camera 10a picks up an image around the top of the chimney 2 regardless of day or night. The thermal camera 10b detects temperature differences between the chimneys 2 and the tops of the chimney 2, that is, the chimney, the smoke, and the air, and converts them into electrical signals, thereby outputting thermal signals for visualizing the subjects by radiant energy. Since the specific configuration of the thermal camera 10b can be easily implemented by those skilled in the art to which the present invention pertains, a detailed description thereof will be omitted.

The first analog-to-digital converter 32 converts the optical image signal into digital data, and the second analog-to-digital converter 34 converts the thermal signal into digital data. The first frame buffer 36 buffers the digitized optical image signal, and the second frame buffer 38 buffers the digitized and thermal signals. The first and second analog-to-digital converters 32 and 34 and the first and second frame buffers 36 and 38 may be implemented by conventional frame grabber cards. The multiplexer 54 multiplexes the digitized optical video signal and the thermal signal into a single bit string, and transmits them to the remote monitoring apparatus 50 through a video signal line such as a coaxial cable.

The gas analyzer 42 receives a measurement signal about the concentration of the pollutant gas, the flow rate and the temperature of the exhaust gas from the exhaust gas sensor 20, amplifies, deforms, and analyzes each measurement value.

The controller 44 controls the operation of the first and second analog-to-digital converters 32 and 34 and the first and second frame buffers 36 and 38, and the signal selection and transmission of the multiplexer 40. The control function of the controller 44 may be performed by a program or may be performed according to a control signal received from the remote monitoring apparatus 50 through the interface port 46. On the other hand, the control unit 44 receives the gas analysis data from the gas analyzer 42 and transmits it to the remote monitoring device 50 through the interface port 46.

3 is a block diagram of an embodiment of the remote monitoring apparatus 50 shown in FIG. 1. In a preferred embodiment, the remote monitoring device 50 is an image separator 52, an output screen configuration unit 54, a display unit 56, a smoke amount calculation unit 58, an image comparison unit 60, a control unit ( 62, an interface port 64, an alarm generator 70, an alert buzzer 72, an SMS transmitter 74, and an input 76.

The image separator 52 separates the optical image signal and the thermal image signal from the signal received from the local data processing apparatus 30, and the output screen configuration unit 54 forms an output image by formatting the optical image and the thermal image. The display unit 56 outputs through the display unit 56.

The smoke amount calculation unit 58 receives the optical image signal and the thermal image signal, and calculates the amount of smoke in the optical image and thermal image, that is, the smoke density. In a preferred embodiment, the smoke amount calculation is calculated separately for each of the optical image and the thermal image. However, in a modified embodiment, the amount of smoke calculation may be made for only one of the optical image and the thermal image. The image comparison unit 60 receives two types of smoke amount data calculated for the optical image and the thermal image from the smoke amount calculation unit 58 and determines whether the smoke amount calculation value exceeds a predetermined reference value.

The control unit 62 receives the gas analysis data from the local data processing device 30 through the interface port 64, processes the data into various forms, and provides the output screen composition unit 54 to the output screen configuration unit 54. Along with the optical image and the thermal image, information such as gas measurement data, analysis statistics data, etc. is included to configure an output screen. In addition, the control unit 62 transmits a control signal for controlling the local data processing device 30 and the camera unit 10 to the local data processing device 30 through the interface port 64.

When the smoke amount calculation value calculated by the smoke amount calculation unit 58 is out of a certain range, the controller 62 provides an alarm message to the output screen configuration unit 54 so that the alarm message is displayed through the display unit 56. And, through the warning buzzer 72 to generate an alarm sound. In this case, the alarm generator 70 causes the SMS transmitter 74 to send an emergency text message to the mobile phone of the person in charge registered in advance.

In addition, the controller 62 generates such an alarm even when the difference between the smoke amount calculated separately calculated based on the optical image and the thermal image is larger than a predetermined reference value. At this time, the controller 62 transmits a control signal to the local data processing apparatus 30 to reset the imaging unit.

The input 76 includes a keyboard, a mouse and / or a joystick, allowing the user to operate the system and enter control commands.

With reference to FIG. 4, the operation of the chimney smoke monitoring system shown in FIG.

The optical image and the thermal image captured by the camera unit 10 are transmitted to the remote monitoring apparatus 50 via the local data processing apparatus 30. In addition, after the measurement signal of the concentration of the pollutant gas and the flow rate and temperature of the exhaust gas measured by the exhaust gas sensor 20 is primarily analyzed by the gas analyzer 42, the remote monitoring device 50 Is transmitted (step 100).

The output screen configuration unit 54 of the remote monitoring apparatus 50 forms an output screen by formatting the optical image and the thermal image and the exhaust gas analysis data into one screen (step 102). An example of the output screen is shown in FIG. As shown in FIG. 5, the optical image 120 is displayed on one side of the upper left and right sides of the screen, and the thermal image 122 is displayed on the other side of the screen. The optical image is displayed in the color mode during the day, and the black and white mode is displayed at night, as described above. On the other hand, a data display area 124 is provided below the output screen. The data that can be displayed in the data display area 124 includes, for example, real-time measurement data for each item received from the local data processing apparatus 30, data change status for each period, analysis / statistical data and graphs, system management information, and administrative information. , Alarm history, reference value exceeding status and history, operation status of each device.

Referring back to FIG. 4, in step 104, the amount of smoke in the optical image and the thermal image, that is, the smoke density, is estimated by the amount of smoke calculation unit 58 (step 104). In operation 106, the image comparator 60 determines whether the smoke amount is outside the reference range. When the smoke amount is out of the reference range, the alarm generator 70 provides an alarm message to the output screen configuration unit 54 so that the alarm message can be displayed through the display unit 56 and through the warning buzzer 72. Make an alarm sound. In addition, the alarm generator 70 causes the SMS transmitter 74 to send an emergency text message to the mobile phone of the person in charge (step 108).

Subsequently, the controller 62 determines whether the difference between the smoke amount calculation values calculated separately based on the optical image and the thermal image is greater than a predetermined reference value (step 114). When the difference between the smoke amount calculation values is larger than the reference value, the alarm generator 70 provides an alarm message to the output screen configuration unit 54 so that the alarm message is displayed through the display unit 56 and the warning buzzer 72. To generate an alarm sound. Then, the controller 62 transmits a control signal for resetting the camera unit 10 to the local data processing apparatus 10 (step 116). Here, steps 114 and 116 may be performed only when the optical image is obtained correctly, for example, only during the day, and may not be performed when the night or weather conditions are not good.

FIG. 6 is a flowchart specifically illustrating a smoke amount estimating process (step 104) illustrated in FIG. 4.

First, the smoke amount calculation unit 58 detects the outline of the smoke portion in the image (operation 150). Next, the smoke amount calculation unit 58 sets a region having a predetermined size in the smoke portion, that is, the portion within the outline, and calculates an average value of pixel values for pixels in the set region (step 152). Subsequently, the smoke amount calculation unit 58 sets a region of a predetermined size in the background portion outside the outline, and then calculates an average value of pixel values for the pixels in the region (step 154). In operation 156, the smoke amount calculator 58 calculates a difference between pixel values of the smoke portion and the background portion. Finally, the smoke amount calculation unit 58 determines the smoke amount based on the difference between the pixel value average values (operation 158). In a preferred embodiment, the look-up table representing the relationship between the average pixel value and the smoke amount is stored in the memory of the remote monitoring apparatus 50, and the smoke amount determination can be made with reference to this look-up table.

7 shows another embodiment of the chimney monitoring system shown in FIG. 1. In the system of FIG. 1, it is installed on the outer wall of the chimney 2 of the camera unit 10, but in the system of FIG. 7, the camera unit 10 is mounted on a support rod 12a installed at a point away from the chimney 2. Is installed. Since other features of the system of FIG. 7 are similar to those of FIG. 1, detailed description thereof will be omitted.

Meanwhile, in the chimney monitoring system of FIG. 1 or 7, when the amount of smoke emitted from the chimney is not large, the image of the smoke is blurred in the image photographed through the camera unit 10, in particular, the optical camera 10a. It may be weak. Especially when the weather is cloudy, as well as when the weather is clear, the presence of smoke or the amount of smoke may not be accurately identified in the image due to the sky or clouds behind the chimney. In view of this, in a preferred embodiment, it is preferable to provide a light shielding plate in the opposite direction of the camera unit 10 on the top of the chimney.

8 shows a light shield plate installed on the top of the chimney in the chimney monitoring system according to this embodiment. The light shielding plate 200 may be installed above the chimney top using the bracket 202 on the opposite side of the camera unit 10. The light shielding plate 200 may be formed by a material such as the chimney 2, for example, concrete, or may be formed using other ceramic materials, metals, engineering plastics, or the like. On the other hand, the light shielding plate 200 is at least a size enough to cover the background of the smoke to prevent the light from the background sky or clouds to enter the camera unit 10, the width is necessarily a chimney ( It does not have to be larger than the diameter of 2) or high enough.

In this case, when the smoke amount calculation unit 58 of the remote monitoring device 50 calculates the amount of smoke from the optical image, the optical image of the chimney 2 photographed in the absence of smoke or in the usual time is stored in the memory. You can save it and refer to it to calculate the amount of smoke.

On the other hand, as shown in Figure 9, when the staircase 210 and the work railing 212 is installed on the upper end of the chimney (2) to check the condition, the light shielding plate 220 is the work railing 212 It may be installed on one side of).

Although the preferred embodiments of the present invention have been described above, the present invention may be modified in various ways without departing from the spirit or essential features thereof and may be embodied in other specific forms. Therefore, the embodiments described above are to be understood in all respects as illustrative and not restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

2: chimney
10: camera unit
30: Local data processing unit
50: remote monitoring device
200, 220: light shroud
210: stairs, 212: work railing

Claims

A system for monitoring the amount of smoke emitted through a chimney
An imaging unit including an optical camera for acquiring an optical image of the smoke and a thermal camera for acquiring a thermal image of the smoke;
An exhaust gas sensor installed at an upper end of the chimney to measure an amount of exhaust gas;
A local data processor for multiplexing the optical image and the thermal image and transmitting the multiplexed image signal; And
A remote monitoring device which receives the multiplexed video signal and forms and outputs one output video by formatting the optical video and the thermal image;
Chimney smoke monitoring system having a.

The chimney smoke monitoring system according to claim 1, wherein the remote monitoring device receives the emission gas amount data and includes the emission gas amount data to form the output image.

The method of claim 1, wherein the remote monitoring device
An amount of smoke calculating unit configured to calculate the amount of smoke using any one of the optical image, the thermal image, and a combination thereof; And
An alarm generating unit for generating an alarm visually or acoustically when the amount of smoke is out of a predetermined reference range;
Chimney smoke monitoring system having a.

The method of claim 1, wherein the remote monitoring device
A smoke amount calculator configured to calculate a first smoke amount based on the optical image and calculate a second smoke amount based on the thermal image;
Chimney smoke monitoring system having a.

The method according to claim 4, wherein the remote monitoring device
An alarm generating unit for generating an alarm visually or acoustically when a difference between the first smoke amount and the second smoke amount is greater than a predetermined reference value;
Chimney smoke monitoring system further comprising.

The method according to claim 4, wherein the remote monitoring device
And a control signal for resetting the imaging unit to the local data processing apparatus when the difference between the first smoke amount and the second smoke amount is larger than a predetermined reference value.

The method according to claim 1,
A light shielding plate provided on the opposite side of the imaging section at the upper end of the chimney to block light from the background of the chimney from entering the imaging section;
Chimney smoke monitoring system further comprising.

Obtaining an optical image and a thermal image of the smoke emitted through the chimney;
Formatting and outputting the optical image and the thermal image to display one output image; And
Calculating an amount of the smoke using any one of the optical image, the thermal image, and a combination thereof, and generating an alarm when the amount of smoke falls outside a predetermined reference range;
Chimney smoke monitoring method comprising a.

The method of claim 8, wherein the alarm generating step
Detecting an outline of a smoke portion in an image used for calculating the smoke amount;
Setting an area of a predetermined size within the outline, calculating an average value of pixel values for pixels in the set area, and calculating an average value of pixel values for a predetermined number of pixels outside the outline; And
Determining the smoke amount based on the difference between the pixel value average values;
Chimney smoke monitoring method comprising a.