Method for Removing Floating Matter from Liquid Imaging Device

Abstract

To provide a method for removing floating matter from a liquid imaging device by which floating matter that has entered a main body case can be easily removed.SOLUTION: A method for removing floating matter 62 from a liquid imaging device 10 in which a first imaging area 38 for imaging particles 12 dispersed in liquid 5 and a second imaging area 39 for imaging supernatant liquid by settling the particles 12 are separated by a partition 40 and formed inside a main body case 20, and which images a liquid surface 35 in a first vertical relation in which the liquid surface 35 inside the main body case 20 is located below an upper end 40a of the partition 40, includes: a first step of changing a vertical relation between the partition 40 and the liquid surface 35 to a second vertical relation in which the liquid surface 35 is located above the upper end 40a of the partition 40; a second step of injecting removal fluid 53 toward the liquid surface 35 and make the floating matter 62 in the second imaging area 39 pass above the partition 40 to move to the first imaging area 38; and a third step of returning the vertical relation between the partition 40 and the liquid surface 35 from the second vertical relation to the first vertical relation.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a method for removing floating substances from a liquid imaging device having, in a main body case, a first imaging chamber for imaging particles dispersed in a liquid and a second imaging chamber for imaging a supernatant liquid in which the particles in the liquid have settled.

Background Art

[0002] Conventionally, as this type of liquid imaging device, for example, as shown in FIG. 15, there is one that images sludge 200 stored in a coagulation tank 208.

[0003] This liquid imaging device 201 includes a first imaging chamber 203 for imaging aggregated flocs 202 dispersed in sludge 200 and a second imaging chamber 205 for imaging a supernatant liquid 204 in which the aggregated flocs 202 have settled, which are partitioned by a partition wall 206 and formed in a cylindrical main body case 207.

[0004] The lower end opening 209 of the first imaging chamber 203 and the lower end opening 210 of the second imaging chamber 205 are submerged below the liquid surface 211 outside the main body case 207, and the lower end opening 209 of the first imaging chamber 203 is located above the lower end opening 210 of the second imaging chamber 205.

[0005] The main body case 207 is provided with a camera 213 for imaging the liquid surface 212 inside the main body case 207. Further, an air supply device 214 is connected to the main body case 207, and compressed air 215 is supplied from the air supply device 214 into the main body case 207. A background plate 216 is provided in the first imaging chamber 203. In the second imaging chamber 205, a turbidity determination marker 217 and a lift pipe 218 for lifting the sludge 200 inside the main body case 207 and discharging it outside the main body case 207 are provided.

[0006] According to this, by supplying compressed air 215 from the air supply device 214 into the main body case 207, the supernatant liquid 204 in the second imaging chamber 205 is discharged outside the main body case 207 through the lift pipe 218 while being accompanied by the bubbles of the compressed air 215. Along with this, the sludge 200 in the coagulation tank 208 flows into the second imaging chamber 205 from the lower end opening 210 of the second imaging chamber 205.

[0007] As a result, the liquid level 212 in the main body case 207 is located below the upper end of the partition wall 206, and the liquid level 212 in the main body case 207 is imaged in such a positional relationship. Based on the image obtained by this imaging, the number, size of the aggregated flocs 202 contained in the sludge 200, the turbidity of the supernatant liquid 204 of the sludge 200, etc. are observed.

[0008] Incidentally, the above liquid imaging device 201 is described, for example, in Patent Document 1 below.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0010] However, in the above conventional form, since the sludge 200 in the coagulation tank 208 is agitated by the agitation device 222, floating substances 220 (flocs containing air, sponges, solidified fats and oils, dead insects, etc.) having a density (specific gravity) smaller than that of water may flow into the second imaging chamber 205 from the lower end opening 210 of the second imaging chamber 205 together with the sludge 200 and float on the liquid level 212 in the second imaging chamber 205.

[0011] If such floating matter 220 stays in the second photographing chamber 205, the upper part of the turbidity determination marker 217 in the second photographing chamber 205 is blocked by the floating matter 220, and the floating matter 220 is reflected in the image of the turbidity determination marker 217. As a result, it becomes difficult to determine the accurate turbidity of the supernatant liquid 204 of the sludge 200, and an inaccurate value different from the actual turbidity may be shown.

[0012] Such floating matter 220 is difficult to be discharged from the inside of the second photographing chamber 205 to the outside of the main body case 207. When the above-mentioned problem occurs, an operator needs to completely lift the entire main body case 207 above the liquid level 211 of the sludge 200 and remove the floating matter 220 by hand, which causes a problem that it takes time to remove the floating matter 220.

[0013] Similarly, the floating matter 220 may flow into the first photographing chamber 203 from the lower end opening 209 of the first photographing chamber 203 and float on the liquid level 212 in the first photographing chamber 203. However, the lower end opening 209 of the first photographing chamber 203 is located above the lower end opening 210 of the second photographing chamber 205. Further, since the sludge 200 in the coagulation tank 208 is being agitated, the floating matter 220 on the liquid level 212 in the first photographing chamber 203 is affected by the flow of the sludge 200 generated during agitation and is easily automatically discharged to the outside of the main body case 207 through the lower end opening 209 of the first photographing chamber 203. Therefore, the problem that the floating matter 220 stays in the first photographing chamber 203 hardly occurs.

[0014] An object of the present invention is to provide a method for removing floating matter in a liquid photographing apparatus that can easily remove floating matter that has entered the main body case.

Means for Solving the Problems

[0015] To achieve the above object, in the first aspect of the present invention, a first photographing area for photographing particles dispersed in a liquid and a second photographing area for photographing a supernatant liquid in which the particles in the liquid have settled are partitioned by a partition and formed in a main body case. The lower end opening of the first photographing area and the lower end opening of the second photographing area are submerged below the liquid level outside the main body case. The lower end opening of the first imaging area is located above the lower end opening of the second imaging area, A method for removing floating matter from a liquid imaging device that images the liquid level in the main body case in a first vertical relationship where the liquid level in the main body case is located below the upper end of the partition body, A first step of changing the vertical relationship between the partition body and the liquid level in the main body case to a second vertical relationship where the liquid level in the main body case is located above the upper end of the partition body; A second step of injecting a fluid toward the liquid level in the main body case and moving the floating matter on the liquid level in the second imaging area through above the partition body and into the first imaging area; And a third step of returning the vertical relationship between the partition body and the liquid level in the main body case from the second vertical relationship to the first vertical relationship.

[0016] According to this, when floating matter flows into the second imaging area from the lower end opening of the second imaging area together with the liquid and accumulates in the second imaging area, first, by executing the first step, since the partition body sinks below the liquid level in the main body case, the liquid level in the main body case is continuously formed over the first imaging area and the second imaging area without being partitioned by the partition body.

[0017] Next, by executing the second step, the floating matter on the liquid level in the second imaging area passes above the partition body and moves into the first imaging area.

[0018] Next, by executing the third step, the liquid level in the main body case is partitioned by the partition body and divided into the liquid level in the first imaging area and the liquid level in the second imaging area.

[0019] Since the lower end opening of the first imaging area is located above the lower end opening of the second imaging area, the floating matter collected in the first imaging area can be easily discharged from the lower end opening of the first imaging area. As a result, it is not necessary to completely lift the entire main body case above the sludge liquid level, and the floating matter that has entered the main body case can be easily removed.

[0020] In the method for removing floating matter from the liquid imaging device according to the second invention, the main body case has its upper end sealed and its lower end open while being submerged below the liquid level. In the first step, by opening the main body case to the atmosphere, the liquid level inside the main body case is raised, and the vertical relationship between the partition body and the liquid level inside the main body case is changed from a first vertical relationship to a second vertical relationship.

[0021] According to this, in the first step, since the air pressure inside the main body case drops to atmospheric pressure, without moving the main body case in the vertical direction, the vertical relationship between the partition body and the liquid level inside the main body case can be changed from the first vertical relationship to the second vertical relationship. As a result, the floating matter that has entered the main body case can be easily removed.

[0022] In the method for removing floating matter from the liquid imaging device according to the third invention, in the third step, by supplying gas into the main body case, the liquid level inside the main body case is lowered, and the vertical relationship between the partition body and the liquid level inside the main body case is restored from the second vertical relationship to the first vertical relationship.

[0023] According to this, in the third step, without moving the main body case in the vertical direction, the vertical relationship between the partition body and the liquid level inside the main body case can be restored from the second vertical relationship to the first vertical relationship. As a result, the floating matter that has entered the main body case can be easily removed.

[0024] The method for removing floating matter from the liquid imaging device according to the fourth invention further includes a fourth step of supplying gas into the main body case and discharging the floating matter in the first imaging area together with the gas from the lower end opening of the first imaging area to the outside of the main body case.

[0025] According to this, after performing the third step, by performing the fourth step, the floating matter in the first imaging area is discharged to the outside of the main body case together with the gas from the lower end opening of the first imaging area. At this time, since the lower end opening of the first imaging area is located above the lower end opening of the second imaging area, the floating matter in the first imaging area can be easily discharged from the lower end opening of the first imaging area. As a result, it is not necessary to completely lift the entire main body case above the liquid level of the sludge, and the floating matter that has entered the main body case can be easily removed.

[0026] In the method for removing floating matter of the liquid imaging device according to the fifth aspect of the present invention, the main body case is inclined with respect to the liquid level, In the first vertical relationship, the position of the liquid level in the main body case corresponds to the uppermost position of the lower end opening of the first imaging area.

[0027] According to this, in the third step, by returning the vertical relationship between the partition body and the liquid level in the main body case from the second vertical relationship to the first vertical relationship, the position of the liquid level in the main body case corresponds to the uppermost position of the lower end opening of the first imaging area. Therefore, in the fourth step, the floating matter in the first imaging area together with the gas can be easily discharged to the outside of the main body case from the uppermost position of the lower end opening of the first imaging area.

[0028] In the method for removing floating matter of the liquid imaging device according to the sixth aspect of the present invention, when it is detected that there is floating matter above the turbidity determination marker provided in the second imaging area, the first to third steps are performed.

[0029] According to this, the floating matter floating above the turbidity determination marker can be easily removed, and the turbidity determination marker in the supernatant liquid can be imaged without being blocked by the floating matter, so that the turbidity can be accurately obtained.

Effects of the Invention

[0030] As described above, according to the present invention, by executing from the first step to the third step, it is not necessary to completely lift the entire main body case above the liquid level of the sludge, and the floating matter that has entered the main body case can be easily removed.

Brief Description of the Drawings

[0031]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Embodiments for Carrying Out the Invention

[0032] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0033] (First Embodiment) In the first embodiment, as shown in FIG. 1, 1 is a part of an industrial wastewater treatment system, and has a coagulation tank 2 and a sedimentation tank 3 installed downstream thereof. The coagulation tank 2 is provided with an injection device 7 for injecting a polymer coagulant 6 into sludge 5 (an example of a liquid) stored in the tank, a stirring device 8 for stirring the sludge 5 in the coagulation tank 2, and a liquid imaging device 10.

[0034] By injecting the polymer coagulant 6 from the injection device 7 into the sludge 5 in the coagulation tank 2 and stirring it with the stirring device 8, large-sized coagulation flocs 12 (an example of particles dispersed in a liquid) are formed in the sludge 5.

[0035] Also, in the sedimentation tank 3, the coagulation flocs 12 in the sludge 5 are sedimented, and the supernatant liquid 13 is taken out from the outlet of the sedimentation tank 3, subjected to neutralization treatment, etc., and then discharged.

[0036] As shown in FIGS. 2 to 4, the liquid imaging device 10 is a device for simultaneously imaging the coagulation flocs 12 dispersed in the sludge 5 and the supernatant liquid 14 in which the coagulation flocs 12 have settled, and includes a main body case 20, a camera 21 (an example of imaging means) fixed in the main body case 20, a background plate 22, a turbidity determination marker 23, a first lighting device 24, a second lighting device 25, an air supply device 27 (an example of a gas supply device) for supplying compressed air 26 (an example of a gas) into the main body case 20, an air release device 28 for opening the inside of the main body case 20 to the atmosphere, a supernatant liquid extraction device 29, and a mounting member 30 for mounting the main body case 20 to the coagulation tank 2.

[0037] The main body case 20 is made of a light-shielding body made of metal or resin, with its upper end sealed and its lower end open while being submerged below the liquid level 33 of the sludge 5. It has a cylindrical peripheral wall portion 31 and a ceiling portion 32 provided at the upper end of the peripheral wall portion 31.

[0038] The inside of the main body case 20 is divided into a semi-cylindrical first imaging area 38 for imaging the aggregated flocs 12 and a semi-cylindrical second imaging area 39 for imaging the supernatant liquid 14. That is, the first imaging area 38 and the second imaging area 39 are partitioned by a partition wall 40 (an example of a partition body) provided in the main body case 20.

[0039] The first imaging area 38 has a first lower end opening 41 that is submerged below the liquid level 33 of the sludge 5 outside the main body case 20, and the second imaging area 39 has a second lower end opening 42 that is submerged below the liquid level 33. The first lower end opening 41 is located above the second lower end opening 42.

[0040] Above the first imaging area 38 and above the second imaging area 39 communicate with each other inside the main body case 20. Also, the liquid level 35 inside the main body case 20 is kept at a lower position than the liquid level 33 outside the main body case 20.

[0041] The upper end portion 40a of the partition wall 40 is set above the first lower end opening 41. As shown in FIG. 2, the vertical relationship between the partition wall 40 and the liquid level 35 inside the main body case 20 is maintained in a first vertical relationship in which the liquid level 35 inside the main body case 20 is located below the upper end portion 40a of the partition wall 40 during imaging. In this case, the position of the liquid level 35 inside the main body case 20 corresponds to the position of the first lower end opening 41.

[0042] The camera 21 is attached to the ceiling portion 32 of the main body case 20 and is located above the liquid level 35 inside the main body case 20, and can simultaneously image the first and second imaging areas 38 and 39. An image processing device (not shown) is connected to the camera 21 via a cable 47.

[0043] The first lighting device 24 is an annular lighting device, which is attached to the ceiling portion 32 of the main body case 20 so as to surround the periphery of the lens portion of the camera 21, and can irradiate the first and second imaging areas 38 and 39 from above the liquid level 35 in the main body case 20. For the light source of the first lighting device 24, for example, an LED or the like is used.

[0044] The air supply device 27 is composed of an air pump or the like, and is connected to the ceiling portion 32 of the main body case 20 through an air supply pipe 48. An air supply valve 49 is provided in the air supply pipe 48.

[0045] The air release device 28 includes an air vent pipe 50 connected to the ceiling portion 32 of the main body case 20 and an air release valve 51 provided in the air vent pipe 50.

[0046] The background plate 22 is a plate for limiting the depth of field, and is provided in the first imaging area 38 and is provided at a predetermined depth position below the liquid level 35 in the main body case 20. For the background plate 22, a translucent resin or glass plate that is easily permeable to light (has light transmissivity) is used.

[0047] The second lighting device 25 is a lighting device for eliminating the shadow of the agglomerated flocs 12 reflected on the upper surface of the background plate 22, and is attached to the partition wall 40 and is located below the background plate 22. For the second lighting device 25, for example, an LED having a waterproof function or the like is used.

[0048] The turbidity determination marker 23 is a flat member, which is provided in the second imaging area 39 and is submerged below the liquid level 35 in the main body case 20. On the upper surface of the turbidity determination marker 23, a black-colored black region 55 and a white-colored white region 56 are provided.

[0049] Below the turbidity determination marker 23 in the second imaging area 39, a floc sedimentation region 57 where the agglomerated flocs 12 in the sludge 5 settle is formed.

[0050] The supernatant liquid extraction device 29 is a device that extracts the supernatant liquid 14 of the sludge 5 in the second imaging area 39 to the outside of the main body case 20, and has a extraction pipe 59 connected to the main body case 20, a pump 60 and an extraction valve 61 connected to the extraction pipe 59.

[0051] In addition, an injection device 54 for injecting water 53 (an example of a fluid for removal, see Fig. 7) toward the liquid surface 35 in the main body case 20 is provided on the peripheral wall portion 31 of the main body case 20. Note that the injection direction of the injection device 54 is inclined so that the water 53 flows from the liquid surface 35 in the main body case 20 toward the first imaging area 38 from the second imaging area 39.

[0052] The operation of the above configuration will be described below.

[0053] As shown in Fig. 1, the polymer flocculant 6 is injected from the injection device 7 into the sludge 5 in the coagulation tank 2, and the sludge 5 in the coagulation tank 2 is stirred by the stirring device 8, thereby forming large-diameter coagulation flocs 12 in the sludge 5 in the coagulation tank 2.

[0054] At this time, as shown in Fig. 2, since the coagulation flocs 12 in the sludge 5 settle in the coagulation floc sedimentation area 57 of the second imaging area 39, a supernatant liquid 14 with few coarsened coagulation flocs 12 appears near the liquid surface 35 in the second imaging area 39, and the turbidity determination marker 23 exists in the supernatant liquid 14 in a state of being submerged below the liquid surface 35 in the main body case 20.

[0055] Then, the first and second imaging areas 38 and 39 are irradiated with the first lighting device 24, and the first and second imaging areas 38 and 39 are photographed with the camera 21, so that an image of the coagulation flocs 12 in the sludge 5 is obtained from the liquid surface 35 of the photographed first imaging area 38, and an image of the turbidity determination marker 23 is obtained from the liquid surface 35 of the photographed second imaging area 39.

[0056] Based on the image of the aggregated flocs 12 thus obtained, the number, size, shape, etc. of the aggregated flocs 12 can be observed. Also, based on the obtained image of the turbidity determination marker 23, the turbidity of the supernatant liquid 14 in the second imaging area 39 can be determined without being hindered by the aggregated flocs 12 in the sludge 5.

[0057] Also, when photographing the liquid level 35 in the main body case 20 as described above, the atmosphere release valve 51 is closed, the air supply valve 49 is opened, and compressed air 26 is supplied from the air supply device 27 into the main body case 20. As a result, the air pressure in the main body case 20 rises above atmospheric pressure, and the liquid level 35 in the main body case 20 is maintained at a position lower than the liquid level 33 outside the main body case 20.

[0058] Furthermore, the compressed air 26 that has flowed into the main body case 20 from the air supply device 27 becomes air bubbles 64 and is discharged from the first lower end opening 41 of the first imaging area 38 to the outside of the main body case 20. As a result, as shown in FIG. 2, the vertical relationship between the partition wall 40 and the liquid level 35 in the main body case 20 is maintained in the first vertical relationship where the liquid level 35 in the main body case 20 is located below the upper end portion 40a of the partition wall 40.

[0059] Also, during imaging, by operating the pump 60 of the supernatant liquid extraction device 29, the supernatant liquid 14 in the second imaging area 39 is extracted outside the main body case 20 through the extraction pipe 59, so that the sludge 5 outside the main body case 20 flows into the second imaging area 39 from the second lower end opening 42.

[0060] As a result, the sludge 5 in the second imaging area 39 is slowly replaced, so that the sludge 5 with the latest properties can always be introduced from the second lower end opening 42 into the second imaging area 39, and its turbidity can be measured.

[0061] Further, the first lower end opening 41 is located above the second lower end opening 42, and since the sludge 5 in the coagulation tank 2 is being stirred by the stirring device 8, the sludge 5 in the first imaging area 38 is slowly replaced under the influence of the flow of the sludge 5 generated during stirring. As a result, the sludge 5 with the latest properties can always be introduced into the first imaging area 38, and its coagulation flocs 12 can be observed.

[0062] Also, as shown in FIG. 5, when suspended matter 62 (flocs containing air, sponges, lumps of grease, dead insects, etc.) mixed in the sludge 5 enters from the second lower end opening 42 into the second imaging area 39 and floats on the liquid surface 35 in the second imaging area 39, the suspended matter 62 is removed by the following method.

[0063] First, as shown in FIG. 6, in the first step, the vertical relationship between the partition wall 40 and the liquid surface 35 in the main body case 20 is changed to a second vertical relationship in which the liquid surface 35 in the main body case 20 is located above the upper end portion 40a of the partition wall 40.

[0064] That is, the pump 60 is stopped to stop the extraction of the supernatant 14, the air supply valve 49 is closed to stop the air supply device 27, and the atmosphere release valve 51 is opened to release the inside of the main body case 20 to the atmosphere. As a result, since the air pressure inside the main body case 20 decreases to atmospheric pressure, the liquid surface 35 inside the main body case 20 can be raised without moving the main body case 20 in the vertical direction, and the vertical relationship can be changed from the first vertical relationship to the second vertical relationship. The liquid surface 35 inside the main body case 20 is continuously formed across the first imaging area 38 and the second imaging area 39 without being partitioned by the partition wall 40. In this case, the liquid surface 35 inside the main body case 20 is at the same height as the liquid surface 33 outside the main body case 20.

[0065] Next, as shown by the solid line in FIG. 7, in the second step, water 53 is sprayed from the injection device 54 toward the liquid surface 35 inside the main body case 20 to move the suspended matter 62 on the liquid surface 35 in the second imaging area 39 to the first imaging area 38. As a result, the suspended matter 62 on the liquid surface 35 in the second imaging area 39 passes above the partition wall 40 and is collected in the first imaging area 38.

[0066] Next, as shown in FIG. 8, in the third step, the vertical relationship between the partition wall 40 and the liquid level 35 in the main body case 20 is returned from the second vertical relationship (see FIG. 7) to the first vertical relationship. That is, the atmosphere release valve 51 is closed, the air supply valve 49 is opened, and the air supply device 27 is operated. As a result, compressed air 26 is supplied from the air supply device 27 into the main body case 20, and the air pressure in the main body case 20 rises above atmospheric pressure. Therefore, without moving the main body case 20 in the vertical direction, the liquid level 35 in the main body case 20 can be lowered to return from the second vertical relationship (see FIG. 7) to the first vertical relationship, and the liquid level 35 in the main body case 20 is partitioned by the partition wall 40 into the liquid level 35 in the first imaging area 38 and the liquid level 35 in the second imaging area 39.

[0067] Thereafter, as shown in FIG. 9, in the fourth step, the compressed air 26 is continuously supplied from the air supply device 27 into the main body case 20, and the floating matter 62 in the first imaging area 38 is discharged out of the main body case 20 from the first lower end opening 41 of the first imaging area 38 together with the compressed air 26 (air bubbles 64).

[0068] At this time, the first lower end opening 41 is located above the second lower end opening 42, and since the sludge 5 near the first lower end opening 41 is constantly replaced under the influence of the flow of the sludge 5 generated by the agitation in the coagulation tank 2, the floating matter 62 in the first imaging area 38 can be easily discharged from the first lower end opening 41.

[0069] As a result, it is not necessary to completely lift the entire main body case 20 above the liquid level 33 of the sludge 5, and the floating matter 62 that has entered the main body case 20 can be easily removed while the main body case 20 is fixed.

[0070] Also, as shown in FIG. 8, in the third step, by returning the vertical relationship between the partition wall 40 and the liquid level 35 in the main body case 20 from the second vertical relationship to the first vertical relationship, the position of the liquid level 35 in the main body case 20 is maintained at the position of the first lower end opening 41. Therefore, as shown in FIG. 9, in the fourth step, the floating matter 62 in the first imaging area 38 can be easily discharged from the first lower end opening 41 to the outside of the main body case 20 together with the compressed air 26 (bubbles 64).

[0071] (Second Embodiment) In the above-described first embodiment, as shown in FIG. 2, the main body case 20 is installed perpendicular to the liquid levels 33 and 35. However, in the second embodiment described below, as shown in FIG. 10, the main body case 20 is inclined at a predetermined inclination angle α in the inclination direction 52 in which the upper part of the partition wall 40 inclines toward the side of the second imaging area 39 and the lower part of the partition wall 40 inclines toward the side of the first imaging area 38 with respect to the liquid levels 33 and 35.

[0072] In this case, in the first vertical relationship, the position of the liquid level 35 in the main body case 20 corresponds to the uppermost position 41a of the first lower end opening 41.

[0073] According to this, when photographing the liquid level 35 in the first and second imaging areas 38 and 39, the compressed air 26 flowing into the main body case 20 from the air supply device 27 becomes bubbles 64 and is discharged from the uppermost position 41a of the first lower end opening 41 in the first imaging area 38 to the outside of the main body case 20. As a result, the vertical relationship between the partition wall 40 and the liquid level 35 in the main body case 20 is maintained in the first vertical relationship in which the liquid level 35 in the main body case 20 is located below the upper end portion 40a of the partition wall 40.

[0074] In addition, when the floating matter 62 floats on the liquid surface 35 within the second imaging area 39, in the third step, similar to the first embodiment, by returning the vertical relationship between the partition wall 40 and the liquid surface 35 within the main body case 20 from the second vertical relationship to the first vertical relationship, since the position of the liquid surface 35 within the main body case 20 corresponds to the uppermost position 41a of the first lower end opening 41, in the fourth step, the floating matter 62 in the first imaging area 38 can be easily discharged outside the main body case 20 from the uppermost position 41a of the first lower end opening 41 together with the compressed air 26 (air bubbles 64).

[0075] (Third Embodiment) In the above-described second embodiment, as shown in FIG. 10, the main body case 20 is inclined at a predetermined inclination angle α in the inclination direction 52 with respect to the liquid surfaces 33, 35. However, in the third embodiment described below, as shown in the phantom line of FIG. 4 and FIG. 11, the main body case 20 is inclined at a predetermined inclination angle α with respect to the liquid surfaces 33, 35 in the direction 91 around the axis extending in the thickness direction of the partition wall 40.

[0076] According to this, when imaging the liquid surface 35 within the first and second imaging areas 38, 39, the compressed air 26 that has flowed into the main body case 20 from the air supply device 27 becomes air bubbles 64 and is discharged outside the main body case 20 from the uppermost position 41a of the first lower end opening 41 in the first imaging area 38. As a result, the vertical relationship between the partition wall 40 and the liquid surface 35 within the main body case 20 is maintained in the first vertical relationship where the liquid surface 35 within the main body case 20 is positioned below the upper end portion 40a of the partition wall 40.

[0077] In addition, when the floating matter 62 floats on the liquid surface 35 of the second imaging area 39, in the third step, similar to the first embodiment, by returning the vertical relationship between the partition wall 40 and the liquid surface 35 within the main body case 20 from the second vertical relationship to the first vertical relationship, since the position of the liquid surface 35 within the main body case 20 corresponds to the uppermost position 41a of the first lower end opening 41, in the fourth step, the floating matter 62 in the first imaging area 38 can be easily discharged outside the main body case 20 from the uppermost position 41a of the first lower end opening 41 together with the compressed air 26 (air bubbles 64).

[0078] (Fourth Embodiment) In the fourth embodiment, when it is detected that there is a floating object 62 above the turbidity determination marker 23, the first to fourth steps are executed. At this time, the detection of the floating object 62 is performed by the method as shown in FIGS. 12 to 14. In FIGS. 12 to 14, for ease of viewing, the black region 55 that should originally be displayed in black is displayed in white.

[0079] The camera 21 takes pictures within the first and second imaging regions 38 and 39, scans the black region 55 in the obtained image of the turbidity determination marker 23 along the first path 71 (refer to the arrow shown by the solid line in FIGS. 12 to 14) to obtain the brightness of the black region 55, and scans the white region 56 along the second path 72 (refer to the arrow shown by the solid line in FIGS. 12 to 14) to obtain the brightness of the white region 56. If the obtained brightness is equal to or higher than a predetermined brightness, it is determined as "bright", and if it is less than the predetermined brightness, it is determined as "dark".

[0080] For example, as shown in FIG. 12, when there is no floating object 62 above the turbidity determination marker 23, by scanning the black region 55 and the white region 56 respectively, all are determined as "dark" in the black region 55, and all are determined as "bright" in the white region 56.

[0081] Also, as shown in FIG. 13, when there is a whitish floating object 62 above the turbidity determination marker 23, by scanning the black region 55 and the white region 56 respectively, all are determined as "bright" in the white region 56, but in the black region 55, the image portion of the floating object 62 is determined as "bright", and the other portions are determined as "dark".

[0082] Also, as shown in FIG. 14, when there is a blackish floating object 62 above the turbidity determination marker 23, by scanning the black region 55 and the white region 56, all are determined as "dark" in the black region 55, but in the white region 56, the image portion of the floating object 62 is determined as "dark", and the other portions are determined as "bright".

[0083] Thus, when scanning the black region 55, as shown in FIG. 12, if all the determinations are "dark", and when scanning the white region 56, if all the determinations are "bright", it is determined that there is no floating matter 62 above the turbidity determination mark 23, and the first to fourth steps are not executed.

[0084] Also, when scanning the black region 55, as shown in FIG. 13, if the determination changes from "dark" to "bright" and from "bright" to "dark", it is determined that there is a whitish floating matter 62 above the turbidity determination mark 23, and the first to fourth steps are executed.

[0085] Also, when scanning the white region 56, as shown in FIG. 14, if the determination changes from "bright" to "dark" and from "dark" to "bright", it is determined that there is a blackish floating matter 62 above the turbidity determination mark 23, and the first to fourth steps are executed.

[0086] In the above fourth embodiment, the black region 55 and the white region 56 in the image of the turbidity determination mark 23 are scanned respectively, and the presence or absence of the floating matter 62 is detected based on the change between "bright" and "dark". However, the presence or absence of the floating matter 62 may also be detected by binarizing the black region 55 and the white region 56 in the image of the turbidity determination mark 23 respectively. According to this, when there is no floating matter 62 above the turbidity determination mark 23, the image of the black region 55 after binarization becomes all black, and the image of the white region 56 after binarization becomes all white.

[0087] Also, when there is a whitish floating matter 62 above the turbidity determination mark 23, in the image of the black region 55 after binarization, the portion corresponding to the floating matter 62 becomes white, and the other portions become black. Also, when there is a blackish floating matter 62 above the turbidity determination mark 23, in the image of the white region 56 after binarization, the portion corresponding to the floating matter 62 becomes black, and the other portions become white.

[0088] As a result, when the area of the white portion in the image of the black region 55 after the binarization process is equal to or greater than a certain area, or when the area of the black portion in the image of the white region 56 is equal to or greater than a certain area, it is determined that the floating matter 62 is present, and the first to fourth steps are executed. Further, when the area of the white portion in the image of the black region 55 after the binarization process is less than a certain area and the area of the black portion in the image of the white region 56 is less than a certain area, it is determined that the floating matter 62 is not present, and the first to fourth steps are not executed.

[0089] In each of the above embodiments, as shown in FIG. 2, the upper end of the main body case 20 is sealed and the lower end is open while being submerged below the liquid level 33 of the sludge 5. However, the upper end of the main body case 20 may be open. In this case, the liquid level 35 inside the main body case 20 becomes the same height as the liquid level 33 outside the main body case 20, and the main body case 20 is movable in the vertical direction. In the first step, by lowering the main body case 20 so that the upper end portion 40a of the partition wall 40 is submerged below the liquid level 35 inside the main body case 20, the vertical relationship between the partition wall 40 and the liquid level 35 inside the main body case 20 can be changed from the first vertical relationship to the second vertical relationship. Further, in the third step, by raising the main body case 20 so that the upper end portion 40a of the partition wall 40 protrudes above the liquid level 35 inside the main body case 20, the vertical relationship between the partition wall 40 and the liquid level 35 inside the main body case 20 can be restored from the second vertical relationship to the first vertical relationship.

[0090] In each of the above embodiments, as shown in FIG. 7, water 53 is being injected from the injector 54 as an example of the removal fluid. However, it is not limited to water 53, and other liquids or gases such as air may be injected.

[0091] In each of the above embodiments, as shown in FIG. 2, compressed air 26 is being supplied from the air supply device 27 into the main body case 20 as an example of the gas. However, gases other than compressed air 26 may be supplied.

[0092] In each of the above embodiments, sludge 5 is given as an example of the liquid, and agglomerated flocs 12 are given as an example of the particles dispersed in the liquid. However, the present invention is not limited to sludge 5 and agglomerated flocs 12, and a liquid other than sludge 5 containing particles other than agglomerated flocs 12 may be photographed using the liquid imaging device 10.

Explanation of Reference Numerals

[0093] 5 Sludge (liquid) 10 Liquid imaging device 12 Agglomerated flocs (particles) 14 Supernatant liquid 20 Main body case 23 Turbidity determination mark 26 Compressed air (gas) 33, 35 Liquid level 38 First imaging area 39 Second imaging area 40 Partition wall (partition body) 41, 42 Lower end opening 41a Highest position 53 Water (removing fluid) 62 Suspended matter

Claims

1. A first imaging area for imaging particles dispersed in a liquid and a second imaging area for imaging the supernatant liquid in which the particles in the liquid have settled are partitioned by a partition body and formed in a main body case. The lower end opening of the first imaging area and the lower end opening of the second imaging area are submerged below the liquid surface outside the main body case. The lower end opening of the first imaging area is located above the lower end opening of the second imaging area. A method for removing floating matter from a liquid imaging device that images the liquid surface in the main body case in a first vertical relationship where the liquid surface in the main body case is located below the upper end of the partition body. A first step of changing the vertical relationship between the partition body and the liquid surface in the main body case to a second vertical relationship where the liquid surface in the main body case is located above the upper end of the partition body. A second step of injecting a fluid toward the liquid surface in the main body case to move the floating matter on the liquid surface in the second imaging area through above the partition body and to the first imaging area. A third step of returning the vertical relationship between the partition body and the liquid surface in the main body case from the second vertical relationship to the first vertical relationship. A fourth step of supplying gas into the main body case to discharge the floating matter in the first imaging area together with the gas from the lower end opening of the first imaging area to the outside of the main body case. The method for removing floating matter from a liquid imaging device is characterized by having these steps.

2. The main body case has its upper end sealed and its lower end open while being submerged below the liquid surface. In the first step, by opening the main body case to the atmosphere, the liquid surface in the main body case is raised to change the vertical relationship between the partition body and the liquid surface in the main body case from the first vertical relationship to the second vertical relationship. The method for removing floating matter from a liquid imaging device according to Claim 1 is characterized by this.

3. In the third step, by supplying gas into the main body case, the liquid surface in the main body case is lowered to return the vertical relationship between the partition body and the liquid surface in the main body case from the second vertical relationship to the first vertical relationship. The method for removing floating matter from a liquid imaging device according to Claim 2 is characterized by this.

4. The main body case is inclined with respect to the liquid surface. In the first vertical relationship, the position of the liquid surface in the main body case corresponds to the uppermost position of the lower end opening of the first imaging area. The method for removing floating matter from a liquid imaging device according to any one of Claims 1 to 3 is characterized by this.

5. When it is detected that there is a floating object above the turbidity determination marker provided in the second imaging area, the method for removing floating objects of the liquid imaging apparatus according to any one of claims 1 to 4, characterized by executing the first to fourth steps.

Images