JPH08201298A - Microorganism monitor - Google Patents

Abstract

PURPOSE: To realize control by fixing the microorganisms in liquid in a sample chamber, dyeing the microorganisms, determining the image of the microorganisms emphasized by dyeing, by the binarization threshold value, thereby extracting and recognizing the microorganism, quantitatively measuring the amount of the microorganisms, and reflecting the microorganism information on the operation control of a monitor. CONSTITUTION: A sample is replaced by water stream, and microorganisms are fixed. A microorganism dyeing device is started, and dyeing liquid is injected into the sample chamber. Then, the dyeing of the microorganism is performed. The image of the dyed microorganisms are picked up with the camera of an image pickup device 200. The image signal is processed by an image processor 400, and the microorganisms are quantitatively measured. The measured value is displayed for guidance on a central monitor 320. In the image processing of the microorganism emphasized by dyeing, the width of the luminance distribution of the microorganisms is narrow and the entire image becomes dark in comparison with the minute change in luminance distribution of the background of sewage. When the low-frequency part between two luminance distributions is determined as the binarization threshold value, the more accurate microorganism information is obtained. The microorganism information is reflected on the operation, and the operation control can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microorganism monitoring device for monitoring microorganisms in a sewage treatment process, for example.

[0002]

2. Description of the Related Art In a sewage treatment process, microorganisms are allowed to ingest organic matter in inflowing sewage in an aeration tank, the microorganisms are allowed to settle in a sedimentation tank, and a supernatant is discharged. In order to improve the quality of water discharged from a sewage treatment plant, it is necessary to improve the shape (size) of microorganisms and improve the sedimentation property. The sewage microorganisms are roughly classified into flocculating microorganisms and filamentous microorganisms, but if filamentous microorganisms proliferate too much, the sedimentation property deteriorates. The deterioration of the sedimentation property is called the bulking phenomenon. When the sedimentation property deteriorates, microorganisms flow out from the sedimentation basin and the quality of the discharged water deteriorates. Therefore, it is important to prevent the filamentous microorganisms from multiplying excessively. Examples of filamentous microorganisms include Sphaerotilus sp.
s) etc. In order to prevent the filamentous microorganisms from breeding all over, it is necessary to continuously and quantitatively measure the types of microorganisms and their appearance amounts or concentrations and reflect them in operation management. In this case, it is important to obtain an accurate microbial state without disturbing the agglutination state of the microorganisms and the living state thereof.

Conventionally, in order to monitor the state of microorganisms, there has been proposed a microorganism image measuring apparatus which images the microorganisms by an image pickup means and uses an image processing technique. Specifically, the image signal (grayscale image) picked up by the image pickup means is binarized by a threshold value, and then the microorganisms are extracted and recognized to be quantitatively measured. As a means for imaging microorganisms, for example, Japanese Patent Laid-Open No.
There is an underwater microscope and the like described in Japanese Patent Publication No. 5-249381, which can continuously sample and image microorganisms. Such an underwater microscope can be placed in the process and continuously image microorganisms. Further, as a microorganism recognition measuring device utilizing image processing technology, for example, Japanese Patent Application Laid-Open No. 5-146
It is described in Japanese Patent No. 791. In this prior art document,
The threshold value is uniquely determined based on the histogram (luminance distribution) of the grayscale image, and the optimum threshold value for obtaining the binarized image signal based on the measurement result of the uniquely determined threshold value. Has been decided.

[0004]

With respect to microorganisms, especially filamentous microorganisms, the brightness of the thread and the background (sewage) are close to each other, and a clear and accurate video signal cannot be obtained because the upper thread is thin. On the other hand, in the microorganism recognition and measurement device using the image processing technique, the threshold value for binarization is uniquely determined based on the histogram of the grayscale image. The brightness of microorganisms and sewage (background) are distributed in two areas. The brightness at the boundary of this region is used as a threshold. However, since the boundaries of the regions overlap, a good binarized image cannot be obtained with a uniquely determined threshold value. The reason why the brightness distribution of the microorganisms and the brightness distribution of the sewage overlap is that the brightness of the fine filamentous microorganisms or the light-colored microorganisms is close to the brightness of the sewage. Some thin filamentous microorganisms or lightly colored microorganisms cannot be ignored in terms of monitoring microorganisms.

In view of the above circumstances, an object of the present invention is to provide a microorganism monitoring apparatus capable of accurately imaging microorganisms, quantitatively measuring the amount of microorganisms, and reflecting such microorganism information in operation management. .

[0006]

According to the present invention, microorganisms in a liquid are fixed in a sample chamber formed by closely adhering two transparent transparent plates for observation, and a stain is injected into the sample chamber to stain the microorganisms. After that, the image signal is obtained by capturing an image.

[0007]

According to the present invention, when the microorganism is dyed, the luminance of the entire microorganism becomes dark and the width of the luminance distribution of the microorganism becomes narrow. Therefore, the brightness of the dyed microorganisms is significantly different from the brightness of the background, and the width of the brightness distribution of the microorganisms is narrowed, so that the brightness of the microorganisms and the brightness of the sewage can be easily distinguished. It also has the effect of emphasizing thin threads and lightly colored microorganisms.
It is possible to easily and accurately determine the threshold value for binarization of the dye-emphasized microorganism image, and to accurately extract and recognize the microorganism.

[0008]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.

In FIG. 1, inflow sewage is first settling tank 10
At 0, large dust or the like is settled and removed, and then flows into the aeration tank 110. The aeration tank 110 has a sludge return pipe 160 from the final settling tank 150.
Return sludge (microorganisms) is supplied via the. The air sent from the blower 140 via the air pipe 130 is diffused into the aeration tank 110 by the diffuser 120. As a result, the returned sludge and waste water supplied into the aeration tank 110 are mixed by stirring. Activated sludge is a lump (a floc) having a particle size of about 0.1 to 1.0 mm, which is an aggregate of microorganisms, and contains several tens of microorganisms. When roughly classified, it consists of an aggregating microorganism and a filamentous microorganism. Activated sludge absorbs oxygen in the supplied air and decomposes organic matter in the wastewater into carbon dioxide and water. A part of the organic matter is applied to the bacterial growth of the activated sludge. The mixed liquid of activated sludge and wastewater is guided to the final settling tank 150, where the activated sludge is subjected to solid-liquid separation by gravity precipitation. The supernatant is usually discharged after chlorine sterilization. On the other hand, a part of the settled sludge in the final settling tank 150 is returned to the aeration tank 110 as the returned sludge via the sludge return pipe 160, and the other settled sludge is discharged from the process as excess sludge from the sludge discharge pipe 170. Sludge return pump 1 and sludge discharge pump 1
65 and a surplus sludge discharge pump 175.

The image pickup device 200 is arranged so as to be immersed in the liquid in the aeration tank 110.
Obtain a magnified image of the microorganisms within 10. The video signal (grayscale image) imaged by the imaging device 200 is input to the on-site monitor 340 via the on-site operation panel 330, and is also input to the image processing device 400 via the on-site operation panel 330 and the central operation panel 300. It The on-site operation panel 330 supplies power to the image pickup apparatus 200, and also gives operation signals such as a television camera installed in the image pickup apparatus 200, lighting, microbial staining, cleaning and sampling. In order to perform remote control, a similar operation signal is also given from the central operation panel 300 to the imaging device 200 via the on-site operation panel 330.

On-site monitor 340 displays an enlarged image of microorganisms from image pickup device 200. The operator refers to the on-site monitor 340 when operating the on-site operation panel 330. Examples of this operation include cleaning of the observation window. The central operation panel 300 receives a video signal transmitted from the site operation panel 330 and transmits it to the image processing device 400, and a device which transmits a control signal for remotely operating the imaging device 200 to the site operation panel 330. Is equipped with. Here, the control signal is, for example, a command to turn on / off a power supply of a television camera, a lighting device, etc. built in the imaging device 200, a command to start cleaning, staining, sampling, a camera diaphragm, a focus operation command, and a motor control. It is a signal such as a command.

The image processing apparatus 400 image-processes the image signal of the enlarged microorganism image from the image pickup apparatus 200 to calculate the identification of the type of microorganism, the size, number and appearance frequency of microorganisms, and based on these calculated values. Determine the microbial status. The state of the microorganisms includes, for example, normal, thread overgrowth (bulking), precursor of bulking, sludge dismantling, and the like.

FIG. 2 shows an example configuration of the image processing apparatus 400.

The image processing device 400 performs image processing on the video signal of the image pickup device 200 to extract and recognize microorganisms, an input device 450 for inputting an external signal, and data transmitted from the image processing 410. A central processing unit (CPU) 520 for calculation, a storage device main memory 600,
It is composed of a supplementary memory 601 and a disk 602.
First, the operation of microorganism recognition measurement in the image processing apparatus 400 will be described.

The image signal from the image pickup device 200 is binarized by the image processing processor 420 of the image processing unit 410, the feature amount is extracted, and the microbial amount such as the microbial size, number and appearance frequency is calculated. Then, these calculated values are sent to the central processing unit (CPU) 52 via the system bus 507.
Send to 0. The central monitor 320 displays the video signal from the image pickup apparatus 200, the processed image from the image processing unit 410, the calculated value, and the like. The image processing memory 440 stores the original image (grayscale image) from the imaging device 200, and also stores the processed image obtained from each processing step in the image processing processor 420.

The central processing unit 520 diagnoses the state of the process based on the calculated value output from the image processor 420. Information necessary for these processes and programs and data are stored in the main memory 600 or the auxiliary memory 6
01 and the disk 602. Central processing unit 52
The diagnostic result of 0 is transmitted to the control circuit 500 and displayed on the central monitor 320. Normally, an operator monitors the state of the process on the monitor screen displayed on the monitor and controls the process.

FIG. 3 shows a detailed structure of an image pickup device 200 provided with a dyeing device 250, which is a feature of the present invention.

In FIG. 3, the television camera 212 is arranged perpendicular to the liquid surface. The imaging device 200 includes two parts, a main body case 210 and a plunger 211,
These two housings have a waterproof structure. The plunger 211 is connected to the main body case 210 via the arm 221. The plunger drive motor 214 installed in the main body case 210 moves the arm 221 up and down via the power converter 215 to move the plunger 211 away from (lower) the main body case 210 or bring them into close contact ( Function). Arm 222
The compression coil spring 223 provided in the above does not receive the compression force when the plunger 211 and the main body case 210 are in close contact with each other, and is installed so as to receive the compression force in the separated state. Arm 2
When 21 is lifted, the plunger 211 is lifted by the elasticity of the coil spring 223 and is brought into close contact with the main body case 210.
When the plunger 211 is in close contact with the main body case 210, the mixed liquid of activated sludge is fixed between the two observation window transparent plates (glass) 217 and 218, and the slit width is about 1 mm.
A sample chamber 230 of about 00 μm is formed. The slit width of the sample chamber 230 is set according to the magnification and characteristics of the television camera 212. Plunger drive motor 21
4 is operated based on a command from the field operation panel 330 or the central operation panel 300.

FIG. 4 shows the state where the plunger 211 is separated from the main body case 210. When a command to move up the plunger driving motor 214 is transmitted in this separated state, the plunger 21 is attached to the main body case 210.
1 comes into close contact. In this case, two observation window glasses 217,
A sample chamber 230 in which microorganisms can be fixed is formed between 218. In this way, by opening and closing the plunger 211, the mixed liquid in the sample chamber 230 is automatically replaced and sampling is performed.

The light from the illumination device 219 provided on the plunger 211 is emitted through the sample fixing observation window glass 218, and the light is guided to the television camera 212 via the observation window glass 217 and the magnifying optical device 216. Get burned.
Here, the brightness signal of the mixed liquid is converted into an electric signal and sent to the site operation panel 330.

The wiper drive motor 213 drives the wiper 220 in response to a command from the site operation panel 330 to wash the surfaces of the observation window glasses 217 and 218. When the wiper is driven, the plunger 211 is separated from the main body case 210.

The microorganism staining device 250 injects the staining solution into the sample chamber 230 via the staining solution transport pipe 251. Details of the microorganism staining device 250 will be described with reference to FIG. The dyeing solution is externally injected and replenished into the dyeing solution storage tank 255 through the dyeing solution replenishing pipe 252. As the dyeing solution, for example, methyl blue is used. When the valve 256 is opened / closed, a fixed amount of the dyeing solution from the dyeing solution storage tank 255 is transferred through the dyeing solution transport pipe 251 to the sample chamber 2.
Guided to 30. Normally, the sample chamber 230 is filled with test water (sewage containing microorganisms), so the valve 256
Is opened, pressure is applied by the pressure pump 257, and a predetermined amount of dyeing solution is injected into the sample chamber 230 via the pipe 251.

On the other hand, since pressure was applied to the injection of the dyeing solution,
Microorganisms in the sample chamber 230 may be washed away at the edges. FIG. 6 shows a cross-sectional view of the structure in which the dyeing solution injection hole is provided in the observation window 217. When several staining solution injection holes 259 are provided on the observation window 217 on average and the staining solution is injected simultaneously from the staining solution injection holes, pressure is applied evenly, so that there is no migration of microorganisms and a still image can be obtained. You can Further, the stain injection hole 259 is located within the imaging field of view of the television camera 212.
Install so that it does not exist in 8. The dyeing device 250 operates replenishment of dyeing solution, opening and closing of valves, starting of pumps, and the like based on commands from the site operation panel 330 or the central operation panel 300. Since the microbial dyeing device 250 and the dyeing liquid transport pipe 251 shown in FIG. 3 are arranged vertically to the observation window 217, there is no concern that the sludge mixed liquid will flow into the dyeing liquid transport pipe 251.

Next, the image pickup device 200 and the image processing device 40.
A measurement procedure based on 0 will be described with reference to FIG.

Measurement of one sample is performed in steps 701 to 70.
It consists of 7. Plunger 2 in step 701
11 is lowered, where the sample is replaced by a water stream. In step 702, the wiper 220 is driven to clean the observation window glasses 217 and 218. In step 703, the plunger 211 is raised to fix the microorganism. In step 704, the microorganism staining device 250 is activated to inject the staining liquid into the sample chamber 230, and the microorganisms fixed in step 703 are stained. Step 7
In 05, a microbe image is captured from the television camera 212. In step 706, the captured video signal is subjected to image processing to quantitatively measure the microorganisms. In step 707,
The calculated value from the image processing apparatus 400 is displayed on the monitor 320 as guidance. The above steps 701 to 707 are activated at any time by the external signal input device, or these activation signals are incorporated into the program of the image processing device 400 and are activated continuously.

Image processing is performed on the microorganism thus stained and emphasized. The histogram of the stained microorganisms is as shown in FIG. FIG. 8 shows a histogram in the case of no staining. As can be understood by comparing FIGS. 8 and 9, the luminance distribution of sewage, that is, the background is almost unchanged, but the luminance distribution of microorganisms is greatly different. As its characteristics, (1) the brightness of the stained microorganisms is far from the brightness of the sewage, (2)
The width of the luminance distribution of the dyed microorganism is narrower than that before dyeing. This is because the dyeing means dyed the microorganisms in a dark and almost the same darkness. From the histogram of FIG. 9, the distinction between the brightness of microorganisms and the sewage can be made much more accurately and easily than in FIG. The threshold value can be easily determined by setting the least frequent portion between these two luminance distributions as the binarization threshold value.

FIG. 10 shows an example in which a dyeing device and an imaging device are separately provided, and the test water in the aeration tank 110 is introduced into the sample chamber of the imaging device by a pipe. in this case,
The imaging device 200 does not have to be directly arranged in the aeration tank 110. The test water in the aeration tank 110 is introduced into the imaging device 200 via the pipe 351. The introduction of the test water is operated by opening and closing the valve 350. The dyeing device 250 includes a dyeing solution storage tank 255, a valve 256, and a dyeing solution transport pipe 251. The dyeing device 250 is provided on the test water transport pipe 351.
By opening and closing the valve 256, a predetermined amount of dyeing solution is mixed with the test water. In this case, the dyeing liquid and the test water are uniformly mixed by utilizing the time taken for the mixed liquid to reach the imaging device.

FIG. 11 shows an example in which a measuring water tank is provided. In this case, the measurement water tank 362 is provided, and the test water in the aeration tank 110 passes through the pipe 361 to be the measurement water tank.
Introduced in 362. The dyeing device dyes the test water introduced into the measurement water tank 362. By opening and closing the valve 256, a predetermined amount of dyeing solution is injected into the measurement water tank 362. In this case, since the amount of test water is larger than that in FIGS. 5 and 9, the stirring device 363 is provided to make the dyeing solution uniform. The stirrer 363 is, for example, a stirrer or an air diffuser of the aeration tank 110. Imaging device 2
00 is placed in this measurement water tank 362.

As described in the above embodiments, the image pickup device is provided with the microbial dyeing device, and in response to the problems such as the discontinuity of the yarn and the inability to take an image of the thin yarn, which have been problems so far,
It is possible to realize a microorganism monitoring device capable of accurately grasping microorganism information. Further, the threshold value of the stained microorganism can be easily and accurately determined, and more accurate information on the microorganism can be obtained. This microbial information can be reflected in operation to detect sludge abnormalities (bulking, sludge dismantling, etc.) at an early stage, and the suppression method and countermeasures can be examined at an early stage.

[0031]

EFFECT OF THE INVENTION The brightness of the dyed microorganisms is significantly different from the brightness of the background, and the dyed and emphasized microorganisms are less susceptible to the performance characteristics of the imaging means. An image can be captured. The microorganism image measuring apparatus can accurately determine the threshold value for binarization of the stained and emphasized microorganism image, and accurately extract and recognize the microorganism. In addition, the microbe image measuring device displays the video signal from the image pickup means on the monitor, recognizes and measures the microbes, guides the microbe information to the operator, reflects the microbe information on the operation, and realizes more accurate operation management. It will be possible.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a detailed configuration diagram showing an example of an image processing apparatus according to the present invention.

FIG. 3 is a detailed configuration diagram showing an example of an image pickup apparatus according to the present invention.

FIG. 4 is an enlarged configuration diagram of a sample chamber of the image pickup apparatus according to the present invention.

FIG. 5 is a detailed configuration diagram of a dyeing device according to the present invention.

FIG. 6 is a detailed configuration diagram of an observation window in the present invention.

FIG. 7 is a flow chart for explaining the operation of the present invention.

FIG. 8 is a characteristic diagram showing an example of a luminance distribution.

FIG. 9 is a characteristic diagram showing a luminance distribution according to the present invention.

FIG. 10 is a configuration diagram showing a main part of another embodiment of the present invention.

FIG. 11 is a configuration diagram showing a main part of another embodiment of the present invention.

[Explanation of symbols]

200 ... Imaging device, 212 ... Television camera, 217, 2
18 ... Observation window glass, 219 ... Illumination device, 250 ... Dyeing device, 320 ... Monitor, 400 ... Image processing device.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Nobuyoshi Yamakoshi 5-2-1 Omika-cho, Hitachi City, Hitachi City, Ibaraki Prefecture Hitachi Co., Ltd. Omika Factory (72) Inventor Yasuo Yahagi 7-chome, Omika Town, Hitachi City, Ibaraki Prefecture No. 1 Hitachi Ltd., Hitachi Research Laboratory (72) Inventor Shoji Watanabe 7-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi Ltd. Hitachi Research Laboratory

Claims (3)

[Claims] 1. A microorganism fixing means for fixing microorganisms in a liquid to a sample chamber formed by closely adhering two transparent transparent plates for observation, and a dyeing agent is injected into the sample chamber fixed with the microorganisms to stain the microorganisms. And an image pickup device having an industrial television camera for picking up the dyed microorganisms fixed in the sample chamber, and a video signal obtained from the image pickup device is binarized to obtain a binarized image signal. A microorganism monitoring device comprising: an image processing device to be obtained; and a monitor for displaying a microorganism image based on the binarized image signal. 2. Microorganism immobilizing means for immobilizing microorganisms in a liquid in a sample chamber formed by closely contacting two observation glass plates, and a dyeing agent is injected into the sample chamber immobilizing the microorganisms to remove the microorganisms. Imaging device having a microbial dyeing means for dyeing to increase the brightness difference between the microorganisms and the background, an illuminating means for irradiating the sample chamber with light, and an industrial television camera for imaging the dyed microorganisms fixed in the sample chamber And an image processing device for binarizing a video signal obtained from the image pickup device to obtain a binarized image signal, and a monitor for displaying a microorganism image based on the binarized image signal. Microbial monitoring device. 3. The microorganism monitoring device according to claim 1, wherein in the image processing device according to claim 1 or 2, the image processing device determines a binarization threshold value from a histogram of the image signal of the stained microorganisms. A microorganism monitoring device characterized by performing binarization processing based on a threshold value.