JP2009080072A - Sludge volume measurement apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a sludge volume measurement apparatus for efficiently and uniformly irradiating a measurement pipe with light from a light emitting source, and obtaining the light sufficient to enable a photodetector to detect transmission light. <P>SOLUTION: In the sludge volume measurement apparatus, a light emitting section 5 for emitting the light from the light source 2 is externally provided on one side face of a measurement tank 1 includes the side faces and the bottom face, and the optical sensor 8 is externally provided on the other side face. The measurement tank 1 has a portion for transmitting the light from the light emitting section 5 to the optical sensor 8. A sludge mixture liquid is introduced into the measurement tank 1 at a fixed liquid level. The light transmitted from the light emitting section 5 to the optical sensor 8 through the measurement tank 1 is detected by the optical sensor 8 after a predetermined time is elapsed. The sludge volume measurement apparatus measures the sludge volume of the sludge mixture liquid from the quantity of the light detected by the optical sensor 8. A first light collection means 3 collects the light from the light source 2, and guided to the light emitting section 5 by a light guide means 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an apparatus for automatically measuring a sludge capacity, which is one of main maintenance management indexes in an organic wastewater treatment facility using an activated sludge method.

  The sludge capacity measurement method, which is one of the main maintenance indicators in the activated sludge method, is described as “activated sludge sedimentation rate” in Section 8 of the first volume of the sewage test method (issued by the Japan Sewerage Association). “The volume of precipitated sludge when the liquid mixture in the reaction tank is allowed to stand for 30 minutes in a 1 liter graduated cylinder is expressed as a percentage of the sample volume of 1 liter”. Here, since the activated sludge sedimentation rate may be different if the volume and shape of the graduated cylinder used are changed, the graduated cylinder used is defined as having a volume of 1 liter and an inner diameter of about 6.5 cm. Generally, wastewater treatment facility maintenance managers operate wastewater treatment facilities appropriately by measuring sludge capacity manually according to the procedure of the sewage test method as a daily work, and using it as a judgment material for maintenance management. . However, large facilities with multiple activated sludge treatment tanks require time-consuming measurements, and measurements at outdoor facilities are affected by rain and sunshine, requiring holidays such as Saturdays, Sundays, national holidays, bon festivals, and New Years. It is a big burden for the maintenance manager.

Therefore, as a device for automatically measuring the sludge capacity, the bottom of the measuring tube with the sample inlet at the top is a valve that can be opened and closed, and a light source is arranged in the axial direction on one side of the measuring tube. An apparatus is disclosed that calculates a sludge capacity by arranging a photodetector on the other of the opposing measuring tubes and taking out the amount of light transmitted through the measuring tube as the amount of electricity of the photodetector (for example, Patent Document 1). reference).
JP-A-51-35363

  However, the activated sludge capacity measuring device described in the above-mentioned conventional patent document 1 is a simple configuration in which a light emission source is arranged on one side and a photodetector on the other side with a measuring tube as a basic configuration. There has been a problem that light from the light source is reflected, refracted, and scattered in the measurement tube and the water in the measurement tube, and sufficient light cannot be obtained for detection by the photodetector.

  Therefore, the present invention realizes a sludge capacity measuring device that can efficiently and uniformly irradiate light from a light source to a measuring tube and obtain sufficient light to detect transmitted light by a photodetector. Objective.

  In order to solve the above-described conventional problems, the sludge capacity measuring device of the present invention includes a light emitting unit that emits light from a light source on one of the outer side surfaces of a measuring tank constituted by a side surface and a bottom surface, and a light receiving unit on the other side. The measuring tank has a part that transmits the light of the light emitting part to the light receiving part, and the sludge mixed liquid is introduced to the measuring tank to a certain liquid level, and after the predetermined time has passed, the light receiving part transmits the measuring tank through the measuring tank. Is a device that measures the sludge volume of the sludge mixed liquid from the detected amount of light detected by the light receiving unit, collects the light from the light source by the light collecting means, and guides the light It leads to the light emitting part by means.

  According to the present invention, it is possible to realize a sludge capacity measuring device that can efficiently and uniformly irradiate light from a light source onto a measurement tank and obtain sufficient light to detect transmitted light by a photodetector.

  The sludge capacity measuring apparatus according to the first embodiment of the present invention includes a light emitting unit that emits light from a light source on one of the outer sides of a measurement tank constituted by a side surface and a bottom surface, and a light receiving unit on the other side. The tank has a part that transmits the light from the light emitting part to the light receiving part. The sludge mixed liquid is introduced to the measuring tank up to a certain liquid level, and after a predetermined time has passed, it passes through the measuring tank and reaches the light receiving part. Is a device that measures the sludge capacity of the sludge mixed liquid from the detected amount of light detected by the light receiving unit, collects the light from the light source by the first light collecting means, and guides the light It leads to the light emitting part by means.

  According to the present embodiment, the light emitted from the light source is collected by the first light collecting unit, and the collected light is guided to the light emitting unit by the light guiding unit and irradiated from the light emitting unit to the measurement tank. Therefore, the light from the light source can be irradiated to the measurement tank without waste, and the light transmitted through the measurement tank can be reliably detected by the light receiving unit.

  According to the second embodiment of the present invention, in the sludge capacity measuring device according to the first embodiment, the light emitting unit has a diffused reflection layer for irregularly reflecting the light guided by the light guide means.

  According to the present embodiment, since the light guided by the light guiding means is uniform in the light emitting part by the irregular reflection layer, the measuring tank can be efficiently and uniformly adjusted by adjusting the size of the light emitting part to the size of the measuring tank. Irradiation can be performed, and unevenness of light transmitted through the measurement tank can be suppressed, so that unevenness of light reaching the light receiving unit can also be suppressed and stable light detection can be performed.

  According to a third embodiment of the present invention, in the sludge capacity measuring device according to the first embodiment, the light guide means is an optical fiber.

  According to the present embodiment, it is possible to install the light source and the condensing unit and the light emitting unit at a distance from each other, and the light source is used in a place where it is easy to access during maintenance such as using a light source with higher output or replacing the lamp. Can be installed.

  In the fourth embodiment of the present invention, in the sludge capacity measuring device according to any one of the first to third embodiments, the measuring tank has a double structure provided with an air layer and has a heat insulating effect. The outer surface of the measuring tank reflects light except for the portion that transmits the light from the light emitting portion to the light receiving portion.

  According to the present embodiment, the sludge mixed liquid in the measurement tank is not easily affected by the outside air temperature or radiant heat, and as a result, the temperature distribution in the measurement tank becomes uniform, and the sludge mixed liquid in the measurement tank generates convection. It becomes difficult, and it becomes possible to measure the sludge capacity stably without being affected by changes in the external environment such as high and low temperatures, night and noon.

  In the fifth embodiment of the present invention, in the sludge capacity measuring apparatus according to any one of the first to third embodiments, the light source is an LED.

  According to the present embodiment, since the LED directly converts electrical energy into light, and no radiant heat is generated, the convection of the sludge mixed liquid in the measurement tank due to the influence of radiant heat generated from the light source is prevented and stabilized. It becomes possible to measure the sludge capacity.

  In the sixth embodiment of the present invention, in the sludge capacity measuring device according to any one of the first to third embodiments, the light receiving unit is configured by arranging a plurality of optical sensors in the depth direction of the measurement tank. is there.

  According to the present embodiment, the number of photosensors that detect light increases according to the sludge settling, so that the sludge capacity can be calculated from the electrical output of the photosensor, It is possible to easily and surely capture the sludge interface and measure the sludge capacity without fine-tuning the calculation parameters according to the type.

  In the seventh embodiment of the present invention, in the sludge capacity measuring device according to the sixth embodiment, the light receiving part is arranged so as to be in close contact with the measuring tank.

  According to the present embodiment, the light transmitted through the measurement tank can be guided to the optical sensor without waste, and the sludge capacity can be reliably measured.

  The eighth embodiment of the present invention is the sludge capacity measuring device according to the sixth embodiment, wherein a second light condensing means is provided between the light receiving part and the measuring tank.

  According to the present embodiment, the light transmitted through the measurement tank can be collected and guided to the optical sensor, even if the sludge mixed liquid is colored or the like and hardly transmits light. This makes it possible to reliably measure the sludge capacity.

  In the ninth embodiment of the present invention, in the sludge capacity measuring device according to any one of the first to third embodiments, the light source is a red light source.

  According to the present embodiment, red has a long wavelength and is difficult to receive light attenuation due to scattering. Therefore, even when there is a lot of suspended solids in the sludge mixture, the sludge volume can be reliably measured. Can do.

  In the tenth embodiment of the present invention, in the sludge capacity measuring device according to any one of the first to third embodiments, the sludge mixed liquid naturally flows down from the upper end of the side surface by overflow.

  According to the present embodiment, when measuring the sludge capacity, it becomes possible to supply the sludge mixed liquid until it overflows from the upper end of the measuring tank, and the sludge mixed liquid overflows from the entire circumference of the upper end of the measuring tank. Since the flow velocity distribution in the measuring tank at the start is uniform, it is possible to obtain a stable value for the measured sludge capacity.

  In an eleventh embodiment of the present invention, in the sludge capacity measuring device according to any one of the first to third embodiments, the measuring tank includes a sludge mixed liquid discharge port and an air diffusion port on the bottom surface, and the sludge After measuring the capacity, the sludge mixed liquid is discharged from the discharge port, and the inside of the measurement tank is cleaned by a bubble jet while being diffused from the air diffusion port while introducing the washing water into the measurement tank.

  According to this embodiment, since the inside of the measurement tank is stirred by the bubble jet, the inner wall of the measurement tank and the washing water can be vigorously brought into contact with each other, so that the inner wall of the measurement tank can be cleaned cleanly. Further, since it is not necessary to add cleaning water to the volume of bubbles, it is possible to save cleaning water.

  According to a twelfth embodiment of the present invention, in the sludge capacity measuring device according to any one of the first to third embodiments, a measuring tank, a light emitting unit, and a light receiving unit are arranged in the main body case, and the outer surface of the main body case Reflects light.

  According to the present embodiment, since the main body case blocks the influence of external light, outside air temperature, and radiant heat, the measuring tank itself only needs to be made of a transparent material, and the configuration of the apparatus can be simplified. It becomes. It is also possible for the maintenance manager to visually check the sludge capacity by removing the main body case for maintenance or the like.

  In a thirteenth embodiment of the present invention, the main body case includes an air inlet and a ventilation device in the twelfth embodiment.

  According to the present embodiment, since the air in the main body case can be stirred while being ventilated, the temperature distribution in the main body case can be kept uniform, and convection of the sludge mixed liquid in the measurement tank can be prevented. It is possible to measure a stable sludge capacity.

  Hereinafter, the sludge capacity measuring device in the example of the present invention is explained with reference to drawings.

  FIG. 1 is a block diagram showing a sludge capacity measuring device in one embodiment of the present invention. In addition, the arrow in a figure shows the flow of sludge liquid mixture. The measuring tank 1 for measuring the sludge capacity is composed of a cylindrical container having a volume of 1 liter and an inner diameter of about 65 mm in accordance with the sewage test method. A light emitting unit 5 is disposed on one side of the measuring tank 1, and an optical sensor 8 is disposed on the other side facing the light emitting unit 5.

  The light source 2 is disposed in the first light collecting unit 3, the first light collecting unit 3 is connected to the light guide unit 4, and the light guide unit 4 is connected to the light emitting unit 5. The light emitting section 5 is provided with an irregular reflection layer 6, and the light guide means 4 is filled with a light guide material such as acrylic, and the light emitting surface of the light emitting section 5 is in close contact with the measuring tank 1.

  The optical sensor 8 is disposed so as to be in close contact with the second light collecting means 7 disposed so as to be in close contact with the measurement tank 1. A plurality of photosensors 8 are arranged in series in the depth direction of the measuring tank 1 and are connected to a display 16 having a plurality of indicators 15 arranged by signal lines 14 of the photosensor. Here, the optical sensor 8 is a phototransistor, a photodiode, a photo IC, or the like.

  The first light collecting means 3 is made of a material that reflects light, such as stainless steel, a plated iron plate, or a mirror. The upper part of the measuring tank 1 is provided with a sludge mixed liquid introducing pipe 11 for introducing a sludge mixed liquid from an aeration tank or the like and a cleaning water introducing pipe 51 for cleaning the inside of the measuring tank 1. Are provided with a discharge port 12 for discharging the sludge mixed solution after the measurement, a sludge mixed solution discharge pipe 17 and a discharge valve 13 connected to the discharge port 12.

  In the above configuration, when measuring the sludge capacity, the sludge mixed liquid in the aeration tank is introduced into the measurement tank 1 from an aeration tank (not shown) by an underwater pump, a land pump, an air lift pump, or the like. The amount of the sludge mixed liquid introduced into the measuring tank 1 is measured by a timer, an electromagnetic flow meter (not shown) or a liquid level sensor (not shown). After introducing the sludge mixed liquid into the measuring tank 1, it is allowed to stand for 30 minutes, and the height of the interface between the concentrated sludge 20 and the sludge supernatant 21 is measured.

  For this reason, the light source 2 is turned on, the light is condensed by the first light collecting unit 3, the collected light is guided to the light emitting unit 5 by the light guiding unit 4, and the light is irregularly reflected by the irregular reflection layer 6 of the light emitting unit 5. Then, the light is made uniform in the light guide means 4, and the surface emitting light is emitted from the light emitting unit 5 to irradiate the measuring tank 1.

  Since the light irradiated into the measuring tank 1 is blocked by the concentrated sludge 20, the optical sensor 8 does not detect the light. On the other hand, since the light is not blocked by the sludge supernatant 21, the optical sensor 8 detects the light. As described above, the sludge interface can be easily and reliably grasped by measuring the number of photosensors 8 that detect light and the number of photosensors 8 that do not detect light and preset positions, thereby measuring the sludge capacity. The standing time (30 minutes) is an example, and can be set from several minutes to several hours as necessary.

  Because of the measuring device having such a configuration, the accuracy of measurement depends on the number of optical sensors. For example, in FIG. 1, the number of optical sensors is 10 and they are arranged at equal intervals, so that the sludge capacity can be measured in increments of 10%. Here, when the number of optical sensors is 20, it becomes possible to measure the sludge capacity in 5% increments. Judging from the actual situation of activated sludge treatment and maintenance, it can be said that the accuracy is enough to withstand practical use in 5% increments.

  The signal of the optical sensor 8 is transmitted to the display 16 through the optical sensor signal line 14. The display device 16 is provided with the same number of indicators 15 as the light sensor 8, and when the light sensor 8 detects light, the indicator 15 is turned on. It becomes possible to know the capacity.

  In addition, it is possible to easily display the number of lighting of the indicator 15 with a number and display the sludge capacity with a number. After measuring the sludge capacity, the discharge tank 13 is opened, the sludge mixed liquid in the measurement tank 1 is discharged, the discharge valve 13 is then closed, and the cleaning water is introduced from the cleaning water introduction pipe 51, thereby the measurement tank. The inside of 1 is cleaned. Here, the washing water may be tap water, industrial water such as groundwater, treated water of a wastewater treatment facility, or the like.

  By setting it as the above structures, the light of the light source 2 can be irradiated to the measurement tank 1 without waste, and the light which permeate | transmitted the measurement tank 1 can be reliably detected with the optical sensor 8. FIG. Moreover, since the light from the light source 2 can be emitted from the light emitting unit 5 to the measurement tank 1, unevenness of light passing through the measurement tank 1 can be suppressed, and unevenness of light reaching the optical sensor can also be suppressed. This makes it possible to detect light stably.

  Here, the light source 2 is generally a fluorescent lamp or an incandescent lamp, but it is best to use an LED. Since the LED directly converts electrical energy into light, there is no generation of radiant heat, preventing convection of the sludge mixture in the measuring tank 1 due to the influence of radiant heat generated from the light source 2, and measuring a stable sludge capacity. It becomes possible.

  Further, the light emitted from the light source 2 may be visible light, but it is desirable that the light is red among visible light. Since red light has a long wavelength of about 700 nm, it has the property that it is difficult for light to be attenuated by suspended matter in water. Can be measured.

  In addition, since the optical sensor 8 collects light from the measuring tank 1 by the second light collecting means 7, even if the sludge mixed solution is colored or the like and hardly has the property of transmitting light, the sludge is surely obtained. Capacitance can be measured. Here, the second light condensing means 7 is a lens made of plastic (acrylic or the like) or glass, and is used to collect as much light transmitted through the measuring tank 1 as possible.

  In addition, since the wavelength at which the sensitivity of the optical sensor 8 is maximized varies depending on the type, it is important to select the optical sensor 8 that matches the wavelength of light from the light source 2.

  FIG. 2 is a structural view of the horizontal section of the optical sensor 8 part of the sludge capacity measuring device in FIG.

  The measuring tank 1 is composed of an inner surface and an outer surface with an air layer 1d interposed therebetween (for the sake of simplicity, it is omitted together with the description in FIG. 1), and both the outer surface and the inner surface are on the light transmitting portion 1a and the optical sensor 8 side. The surface is made of a transparent material so as to transmit light like the light receiving / transmitting portion 1b. A light shielding layer 1c (shown by a thick line in FIG. 2) is provided on the outer surface except for the light transmission / transmission part 1a and the light reception / transmission part 1b so as to reflect light from the outside.

  Here, the material of the measuring tank 1 is preferably plastic or glass. In addition, the light shielding layer 1c may be simply aluminum foil, but it is also possible to use a paint that easily reflects light, such as silver or white, after being undercoated such as black.

  As described above, by providing the measurement tank 1 with the air layer 1d, the measurement tank 1 has a heat insulating effect, and the outer surface of the measurement tank 1 reflects light. For this reason, the sludge mixed liquid in the measurement tank 1 is not easily affected by the outside air temperature or radiant heat. As a result, the temperature distribution in the measurement tank 1 becomes uniform, and the sludge mixed liquid in the measurement tank 1 does not easily generate convection. The sludge capacity can be measured stably without being affected by changes in the external environment such as high and low temperatures, night and daytime.

  FIG. 3 shows a configuration diagram when the light source 2 and the light emitting unit 5 are connected by the light guide means 4. The light from the light source 2 is collected by the first light collecting means 3 and reaches the light emitting unit 5 by the light guiding means 4. Here, an optical fiber cable 22 is used for a part of the light guide means 4. By doing so, it is possible to install the light source 2 and the first light condensing means 3 and the light emitting unit 5 at a distance away from each other, and use a light source 2 with a higher output or maintenance such as replacement of the light source 2. It becomes possible to install the light source 2 in a place that is sometimes easily accessible.

  FIG. 4 is a block diagram showing another embodiment of the sludge capacity measuring device in FIG. The same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

  The secondary measurement liquid receiving tank 31 is disposed on the upper side of the measurement tank 1 so as to surround the side surface of the measurement tank 1, the bottom surface of the secondary measurement liquid receiving tank 31 is inclined with respect to the side surface of the measurement tank 1, and the inner side of the bottom surface has an acute angle. It has a shape that touches. A secondary measurement liquid discharge port 32 is disposed on the bottom surface of the secondary measurement liquid receiving tank 31. A secondary measurement liquid receiving tank lid 33 is disposed above the secondary measurement liquid receiving tank 31, and a sludge mixed liquid inlet 34 is disposed in the secondary measurement liquid receiving tank lid 33.

  Light from the light source 2 is guided to the light emitting unit 5 by an optical fiber cable 22. A diffuser port 37 is disposed on the bottom surface of the measuring tank 1, and a diffuser valve 35 and a diffuser blower 36 are connected to the diffuser port 37 through a pipe. Further, the optical sensor 8, the second light collecting means 7, and the optical sensor signal line 14 are protected from the sludge mixed solution by the optical sensor cover 38.

  In the above configuration, when measuring the sludge capacity, the sludge mixed liquid is introduced into the measuring tank 1 from the sludge mixed liquid inlet 34 and the sludge mixed liquid is discharged from the secondary measured liquid outlet 32 into the aeration tank. Thereafter, the introduction of the sludge mixed liquid is stopped, and the sludge capacity is measured in the same procedure as in FIG.

  After measuring the sludge capacity, the discharge valve 13 is opened, the sludge mixed solution is discharged, the discharge valve 13 is closed, the cleaning water is introduced from the cleaning water introduction pipe 51, and the measuring tank 1 is maintained for about 10 to 30 seconds. Then, the washing water is overflowed to the secondary measurement liquid receiving tank, and then the aeration blower 36 is operated while introducing the washing water, and then the aeration valve 35 is opened to wash the measurement tank 1 with a bubble jet. . The bubble jet overflows from the measurement tank 1 and is sent from the secondary measurement liquid discharge port 32 to the aeration tank.

  Here, when measuring the sludge capacity, if a sludge mixed liquid equal to or larger than a predetermined (1 liter) sludge mixed liquid is introduced into the measuring tank 1, it overflows from the upper end of the measuring tank 1. It becomes possible to measure the liquid mixture. The flow rate of the sludge mixed liquid introduced into the measuring tank 1 is desirably 2 liters / minute or more. This is because when the flow rate is too small, the sludge mixed liquid starts to settle while the sludge mixed liquid is introduced into the measuring tank 1.

  In addition, since the sludge mixed liquid overflows from the entire circumference of the upper end of the measuring tank 1, the flow velocity distribution in the measuring tank 1 at the start of the sludge capacity measurement is made uniform, so that the measured value of the sludge capacity is stabilized.

  In addition, since the inside of the measuring tank 1 filled with the washing water is stirred by the bubble jet, the inner wall of the measuring tank 1 and the washing water can be vigorously brought into contact with each other, so that the inner wall of the measuring tank 1 can be washed cleanly.

  Further, since it is not necessary to add cleaning water to the volume of bubbles, it is possible to save cleaning water. Here, tap water, treated water for wastewater treatment, industrial water, and the like are used as washing water.

  FIG. 5 shows a configuration diagram in which the sludge capacity measuring device of FIGS. 1 and 4 is arranged in the main body case 41. A measuring device 45 is disposed in the main body case 41 via a measuring device fixing leg 46. The sludge mixed liquid introduction pipe 61 introduces the sludge mixed liquid into the measuring device 45, and the sludge mixed liquid discharge pipe 67 discharges the sludge mixed liquid.

  The measurement result is transmitted to the display 16 outside the main body case by the optical sensor signal line 14. A ventilation fan 42 for ventilation is disposed at the upper part of the main body case 41, and an air inlet 43 is disposed at the lower part of the main body case 41.

  Note that an inclination adjusting means 44 is disposed below the main body case 41 so that the inclination of the measuring device 45 can be corrected. The outer surface of the main body case 41 is made of a material that reflects light (stainless steel) and a color (white, silver).

  By adopting such a configuration, the main body case 41 blocks the influence of external light, outside air temperature, and radiant heat. Therefore, the measurement tank does not need to be provided with the light shielding layer 1c described in FIG. 2, and is made of a transparent material. This makes it possible to simplify the structure of the apparatus.

  Further, it is possible to open the main body case 41 for maintenance or the like, and the maintenance manager can visually confirm the sludge capacity.

  Moreover, since the air in the main body case 41 can be stirred while ventilating by operating the ventilation fan 42, the temperature distribution in the main body case 41 can be kept uniform, and a stable sludge capacity is measured. It becomes possible.

  The sludge capacity measuring device according to the present invention can be applied to the maintenance management of an activated sludge treatment tank.

The block diagram which shows the sludge capacity | capacitance measuring apparatus in one Example of this invention The block diagram which shows the cross section of the sludge capacity | capacitance measuring apparatus in FIG. 1 of this invention Configuration diagram when the light source 2 and the light emitting unit 5 are connected by an optical fiber The block diagram which shows the other Example of the sludge capacity | capacitance measuring apparatus in FIG. Configuration diagram in which the sludge capacity measuring device of FIGS. 1 and 4 is disposed in the main body case

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Measurement tank 1a Light emission permeation | transmission part 1b Light reception permeation | transmission part 1c Light-shielding layer 1d Air layer 2 Light source 3 1st condensing means 4 Light guide means 5 Light emission part 6 Diffuse reflection layer 7 2nd light condensing means 8 Optical sensor 11, 61 Sludge Mixed liquid introduction pipe 12 Discharge port 13 Discharge valve 14 Optical sensor signal line 15 Indicator 16 Display unit 17, 67 Sludge mixed liquid discharge pipe 20 Concentrated sludge 21 Sludge supernatant 22 Optical fiber cable 31 Secondary measurement liquid receiving tank 32 Secondary measurement liquid discharge Outlet 34 Sludge mixture introduction port 35 Air diffuser valve 36 Air diffuser blower 37 Air diffuser port 38 Optical sensor cover 41 Main body case 42 Ventilation fan 43 Air intake port 44 Inclination adjusting means 45 Measuring device 46 Measuring device fixing leg 51 Washing water introduction pipe

Claims (13)

A light-emitting unit that emits light from the light source is provided on one of the outer sides of the measurement tank constituted by a side surface and a bottom surface, and a light-receiving unit is provided on the other side. The sludge mixed liquid is introduced to the measurement tank to a predetermined liquid level, and after a predetermined time has passed, the light that passes through the measurement tank from the light emitting part and reaches the light receiving part is detected by the light receiving part, A device for measuring the sludge volume of the sludge mixed liquid from the detected amount of light detected by the light receiving unit, collecting the light from the light source by the first light collecting unit, and guiding the light to the light emitting unit by the light guiding unit Capacity measuring device. 2. The sludge capacity measuring apparatus according to claim 1, wherein the light emitting unit has a diffused reflection layer for irregularly reflecting the light guided by the light guide means. 2. The sludge capacity measuring apparatus according to claim 1, wherein the light guiding means is an optical fiber. The measuring tank has a double structure provided with an air layer and has a heat insulating effect, and the outer surface of the measuring tank reflects light except for a part that transmits light from the light emitting part to the light receiving part. The sludge capacity measuring device according to any one of claims 1 to 3. The sludge capacity measuring device according to any one of claims 1 to 3, wherein the light source is an LED. The sludge capacity measuring device according to any one of claims 1 to 3, wherein the light receiving unit includes a plurality of optical sensors arranged in a depth direction of the measuring tank. The sludge capacity measuring device according to claim 6, wherein the light receiving unit is disposed so as to be in close contact with the measurement tank. The sludge capacity measuring apparatus according to claim 6, further comprising a second light collecting unit between the light receiving unit and the measuring tank. The sludge capacity measuring device according to any one of claims 1 to 3, wherein the light source is a red light source. A secondary measurement liquid receiving tank is disposed so as to surround the side surface of the measurement tank, and the secondary measurement liquid receiving tank includes a lead-out port through which the sludge mixed liquid is led out, and the sludge mixed liquid naturally flows down from the upper end of the side face by overflow. The sludge capacity measuring device according to any one of claims 1 to 3, wherein: The measurement tank is provided with a sludge mixed liquid discharge port and an air diffusion port on the bottom surface, and after measuring the sludge capacity, discharging the sludge mixed liquid from the discharge port and introducing cleaning water into the measurement tank, The sludge capacity measuring device according to any one of claims 1 to 3, wherein the inside of the measurement tank is washed with a bubble jet by aeration from an air outlet. The sludge capacity measuring device according to any one of claims 1 to 3, wherein the measuring tank, the light emitting unit, and the light receiving unit are disposed in a main body case, and an outer surface of the main body case reflects light. The sludge capacity measuring device according to claim 12, wherein the main body case includes an air inlet and a ventilation device.