JP2016203102A - Treatment system and treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treatment system and a treatment method which enable the filtration of a treatment object liquid to be continued even during a cleaning process and furthermore a high cleaning effect to be obtained.SOLUTION: A treatment system of an embodiment has a treatment tank, a bubble generating device, detection means, and a control part. The treatment tank has a supply part which is supplied with treatment object liquid, a filter, a first discharge part that discharges a treated liquid, and a second discharge part that discharges a part of a treatment object liquid. The filter has a plurality of through-holes and a plurality of microstructures which has a smaller maximum outer dimension than an average hole diameter of the through-hole. The bubble generating device can supply bubbles to the treatment object liquid. The detection means detects a filtration performance of the filter. When the control part judges that cleaning is needed on the basis of output from the detection means, the control part supplies the treatment object liquid with bubbles added by the bubble generating device to the supply part and filters a part of the treatment object liquid with the filter to discharge the remainder of the treatment object liquid to the second discharge part along with solid contents sedimented on the filter.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a processing system and a processing method.

As a method for separating and removing suspended substances contained in water (hereinafter sometimes referred to as “SS particles”), there is a method of filtering using a filter.
When the water to be treated containing SS particles is filtered through a filter, a cake made of SS particles is formed on the surface of the filter, and the process proceeds to cake filtration. In cake filtration, the filtration flow rate decreases as the thickness of the cake increases. For this reason, the washing | cleaning which stops filtration intermittently and removes a cake from a filter using clear water is performed.

  However, in the conventional technique, there are cases where the SS particles cannot be sufficiently removed from the filter even after washing. In addition, in the conventional technology, the filtration is stopped and the washing is performed. Therefore, in order to enhance the washing effect, the operation rate (filtration time / processing system running time) decreases as the number of washings and the washing time are increased. It was.

JP 2008-180206 A JP 2007-216102 A JP 2013-248607 A

Tao Hang, Ming Li, Qin Fei and Dali Mao, Characterization of nickel nanocones routed by electrodeposition without any template, Nanotechnology, 19 (2008) 035201 (5pp) S.Chakraborty of organic additives in nickel planting, Transactions of the Metal Finishers’Association of india, Vol.12, No.3-4 (2003)

  The problem to be solved by the present invention is to provide a processing system and a processing method capable of continuing the filtration of the liquid to be processed even during the cleaning process and obtaining a high cleaning effect.

The processing system of the embodiment includes a processing tank, a bubble generation device, a detection unit, and a control unit.
The processing tank is supplied to the supply unit to which the liquid to be processed is supplied, the filter for filtering the solid content in the liquid to be processed, the first discharge unit for discharging the processing liquid that has passed through the filter, and the supply unit. A second discharge unit configured to discharge a part of the liquid to be treated; The filter includes a plurality of through holes and a plurality of fine structures formed on at least a surface on the primary surface side into which the liquid to be treated flows and having a maximum outer dimension smaller than an average hole diameter of the through holes.
The bubble generating device can supply bubbles to the liquid to be processed supplied to the supply unit.
The detection means detects the filtration performance of the filter.
The control unit determines whether or not the filter needs to be cleaned based on the output from the detection means. When it is determined that the cleaning is necessary, the control unit supplies the liquid to be processed to which bubbles are added by the bubble generation device to the supply unit, and filters a part of the liquid to be processed with the filter. The remaining part of the liquid to be treated is discharged from the second discharge part together with the solid content deposited on the filter. When the control unit determines that the cleaning is unnecessary, the control unit supplies the processing target liquid to which the bubbles are not added to the supply unit, filters a part of the processing target liquid through the filter, and supplies the processing target liquid. The process which discharges the remainder of this from the said 2nd discharge part is performed.

The schematic diagram which shows the processing system of 1st Embodiment. The plane schematic diagram which shows the filter installed in the processing tank. The principal part expansion schematic diagram which shows a part of filter. The SEM photograph in case a fine structure is a needle-like structure. The SEM photograph in case a fine structure is a polyhedron shape. The SEM photograph in case a fine structure is a polyhedron shape. The schematic diagram which shows the processing system of 2nd Embodiment. Explanatory drawing for demonstrating the processing system in which the other washing nozzle was installed in the processing tank. The external appearance perspective view which showed the filter other example. Sectional drawing when the filter shown in FIG. 9 is seen from the end face side. The plane schematic diagram which showed the other example of the filter. The plane schematic diagram which showed the other example of the filter. The plane schematic diagram which showed the other example of the filter. Schematic which showed the other example of the filter formed in the cylindrical shape. Sectional drawing when the filter shown in FIG. 14 is seen from the end face side. The principal part expanded sectional view which shows the internal peripheral surface side of the filter shown in FIG. The principal part expanded sectional view which shows the internal peripheral surface side in the other example of a filter. The external appearance perspective view which shows the other example of a filter. The external appearance perspective view which shows the other example of a filter. The SEM photograph of the filter of Example 1 after a filtration test. The photograph of the filter of Example 1 before washing | cleaning. The photograph of the filter of Example 1 after washing.

(First embodiment)
Hereinafter, a processing system and a processing method of an embodiment will be described with reference to the drawings.
FIG. 1 is a schematic diagram illustrating a processing system according to the first embodiment. The processing system 100 includes a liquid tank 101 to be processed, a processing tank 102, a pump 106, a bubble generator 109, a processing liquid tank 103, a concentrated sludge tank 104, and a pipe connecting them. . The processing system 100 shown in FIG. 1 is of a cross-flow type in which the liquid to be treated flows on the surface of the filter 10 on the side of the liquid area 102a to be treated and flows through the filter 10 while flowing in parallel.

  The liquid tank 101 to be processed stores the liquid to be processed. Examples of the liquid to be treated include water containing SS particles. The liquid tank 101 to be processed may be provided with a stirrer for stirring the liquid tank 101 to be processed. The shape, capacity, material, and the like of the liquid tank 101 to be processed can be appropriately determined according to the use of the processing system 100, and are not particularly limited.

The processing tank 102 includes a supply unit 141 to which the liquid to be processed is supplied, a filter 10 that filters solids in the liquid to be processed, a first discharge unit 142 that discharges the processing liquid that has passed through the filter 10, and a supply unit. And a second discharge portion 143 that discharges a part of the liquid to be processed supplied to 141.
In the treatment tank 102, the treatment liquid is filtered by the filter 10 to remove an object to be filtered (solid content) such as SS particles from the treatment liquid, thereby generating a treatment liquid. The outer shape of the processing tank 102 is not particularly limited, and, for example, one having a flat shape with a large area in a plan view and a small area in a side view is used.

  The treatment tank 102 is partitioned by the filter 10 into a treatment liquid region 102a and a treatment liquid region 102b. The filter 10 installed in the processing tank 102 is installed substantially horizontally in the vertical center of the processing tank 102. Therefore, the inside of the processing tank 102 is divided into upper and lower portions by the filter 10. The upper side of the filter 10 is a processing liquid region 102a, and the lower side of the filter 10 is a processing liquid region 102b.

The inflow pipe 108 a is connected to the liquid tank 101 to be processed and the supply unit 141 of the processing tank 102. The supply unit 141 of the processing tank 102 is provided on the upper surface of the wall surface of the processing tank 102.
A pump 106 is installed in the inflow pipe 108a. The pump 106 pumps the liquid to be processed contained in the liquid tank 101 to be processed to the supply unit 141 of the processing tank 102.

  A bubble generator 109 is connected to the inflow pipe 108a through a pipe 108c. The bubble generating device 109 can supply bubbles to the liquid to be processed supplied to the supply unit 141. In the present embodiment, the bubble generating device 109 supplies bubbles to the liquid to be processed passing through the inflow pipe 108a through the pipe 108c at the time of cleaning, which will be described later, and generates a bubble-containing liquid to be processed.

  As the bubble generation device 109, a conventionally known device can be used, and it is preferable to use a device capable of generating a bubble-containing liquid to be processed containing bubbles of 1 to 100 μm. Examples of the bubble generation device 109 that can generate a bubble-containing liquid to be processed including bubbles of 1 to 100 μm include an air introduction unit that introduces air into the liquid to be processed, and air bubbles that are introduced into the liquid to be processed. And the like having a mixing part dispersed in a shape. As the mixing unit used in the bubble generating device 109, for example, a liquid to be processed and an introduced air are passed through an orifice having a plurality of small holes, and the liquid to be processed and the introduced air are mixed by a static mixer. Examples thereof include devices.

  The outflow pipe 108 f is connected to the second discharge part 143 and the valve 107 of the processing tank 102. The 2nd discharge part 143 of the processing tank 102 is provided in the wall surface upper part of the processing tank 102. FIG. The connection position (second discharge part 143) between the outflow pipe 108f and the processing tank 102 is substantially the same as the connection position (supply part 141) between the inflow pipe 108a and the processing tank 102 via the central portion in plan view of the processing tank 102. Opposite positions.

  The valve 107 is a three-way valve. The outflow pipe 108f communicates with the second discharge part 143 of the processing tank 102 and the return pipe 108b or the discharge pipe 108d by switching the valve 107. The return pipe 108 b is connected to the liquid tank 101 to be processed. Therefore, the liquid to be processed can be circulated between the liquid tank 101 and the liquid tank 102 via the inflow pipe 108a, the outflow pipe 108f, and the return pipe 108b. The discharge pipe 108 d is connected to the concentrated sludge tank 104.

  The processing liquid tank 103 stores the processing liquid supplied from the first discharge part 142 of the processing tank 102 via the processing liquid pipe 108e. The treatment liquid is generated when the liquid to be treated passes through the filter 10 in the treatment tank 102 from the primary surface 11a side to the secondary surface 11b side. The shape, capacity, material, and the like of the processing liquid tank 103 can be appropriately determined according to the use of the processing system 100, and are not particularly limited.

  The processing liquid pipe 108e is provided with a flow meter 110 for measuring the flow rate of the processing liquid passing through the processing liquid pipe 108e as a detecting means for detecting the filtration performance of the filter 10. As the flow meter 110, one that continuously measures the flow rate of the processing liquid may be used, or one that measures the flow rate of the treatment liquid every predetermined time may be used. The measurement result of the flow rate of the liquid to be processed measured by the flow meter 110 is sent to the control unit 120.

  Based on the output from the flow meter 110 (detection means), the control unit 120 determines whether or not the filter 10 needs to be cleaned. If it is determined that cleaning is necessary, the control unit 120 executes cleaning and determines that cleaning is not necessary. In some cases, the process is executed. In the present embodiment, the control unit 120 determines whether or not the filter 10 needs to be cleaned depending on whether or not the measurement result of the flow rate of the processing liquid sent from the flow meter 110 is equal to or less than a predetermined threshold value. Thus, the bubble generating device 109 and the valve 107 are controlled. Whether the filter 10 needs to be cleaned by the control unit 120 may be determined each time a measurement result of the flow rate of the processing liquid is sent from the flow meter 110, or may be determined at regular intervals.

  The function of determining whether or not the measurement result of the flow rate of the processing liquid in the control unit 120 is equal to or less than a threshold and the function of controlling the bubble generation device 109 and the valve 107 based on the determination result are, for example, a computer This is realized by the functions provided in the central processing unit.

  When the control unit 120 determines that cleaning is necessary, the control unit 120 controls the bubble generation device 109 and the valve 107 to drive the bubble generation device 109 and switch the valve 107 to the outflow pipe 108f. The discharge pipe 108d is connected. As a result, the liquid to be processed (bubble-containing liquid to be processed) to which bubbles are supplied from the bubble generating device 109 is supplied to the supply unit 141, and a part of the liquid to be processed contained in the bubble-containing liquid to be processed is filtered. And the remaining part is washed together with the solid content deposited on the filter 10 to be discharged from the second discharge part 143.

  When the control unit 120 determines that the cleaning is unnecessary, the control unit 120 controls the bubble generation device 109 and the valve 107 to switch the valve 107 in a state where the bubble generation device 109 is stopped and to discharge the piping. 108f communicates with the discharge pipe 108d. As a result, the liquid to be processed to which no bubbles are added is supplied to the supply unit 141, a part of the liquid to be processed is filtered by the filter 10, and the remaining part of the liquid to be processed is discharged from the second discharge unit 143. .

  The concentrated sludge tank 104 stores a concentrated liquid containing a lot of SS particles removed from the liquid to be treated. The concentrated sludge tank 104 is supplied from the treated liquid region 102a of the treatment tank 102 through the outflow pipe 108f and the discharge pipe 108d. The shape, capacity, material, and the like of the concentrated sludge tank 104 can be appropriately determined according to the use of the processing system 100, and are not particularly limited.

FIG. 2 is a schematic plan view showing a filter installed in the processing tank 102.
The filter 10 has a plurality of through holes 13, 13... And at least a plurality of fine structures formed on the surface of the primary surface 11a side (see FIG. 1) into which the liquid to be treated flows. In the present embodiment, the fine structure is formed on the entire surface of the filter 10. That is, the fine structure is formed so as to cover the primary surface (inflow surface) 11 a of the filter 10, the secondary surface (outflow surface) 11 b through which the liquid to be processed flows out, and the inner wall surface of the through hole 13. . The fine structure has a maximum outer dimension smaller than the average hole diameter of the through holes 13. The fine structure is preferably formed of a metal or an alloy.

  The average hole diameter of the through holes 13 is preferably 0.1 μm to 5 mm. When the average pore diameter of the through holes 13, 13... Is 0.1 μm or more, it becomes easy to secure a filtration flow rate in the treatment system 100, and the liquid to be treated can be efficiently filtered. When the average hole diameter of the through holes 13, 13... Is 5 mm or less, a cake is easily formed. Therefore, the filtration performance by cake filtration can be enhanced, and a high-quality treatment liquid from which SS particles are sufficiently removed can be obtained. can get. The average hole diameter of the through holes 13, 13... Means the average value of the diameters of the inscribed circles of the plurality of through holes 13, 13.

  The fine structure may have at least one of a cone shape, an elliptical cone shape, a polygonal pyramid shape, a truncated cone shape, an elliptical truncated cone shape, and a polygonal truncated cone shape, or a polyhedral shape. It may be.

  Next, with reference to FIG. 3 and FIG. 4, when the fine structure is at least one of a conical shape, an elliptical cone shape, a polygonal pyramid shape, a truncated cone shape, an elliptical truncated cone shape, and a polygonal truncated cone shape As an example, a case where the fine structure is a needle-like structure having a tapered shape from the proximal end toward the distal end will be described. FIG. 3 is an enlarged schematic view of a main part showing a part of the filter. FIG. 4 shows an SEM photograph (secondary electron image (SEI), 15.0 kV, 20000 times) when the fine structure is a needle-like structure. When the fine structure is a needle-like structure, the fact that the maximum outer dimension is smaller than the average hole diameter of the through-hole 13 means that the height dimension of the needle-like structure is smaller than the average hole diameter of the through-hole 13. .

In the filter 10 shown in FIG. 3, SS particles captured from the liquid to be treated are attached to some of the plurality of fine structures 5.
A fine structure 5 shown in FIG. 3 is formed of a plating layer 3 disposed on a substrate 11. A base layer 4 is formed between the plating layer 3 and the substrate 11.

  In the present embodiment, the substrate 11 has a mesh shape. As shown in FIG. 2, the mesh-like base material 11 may be one in which the wire is twilled or plain woven. In this embodiment, since the mesh-like thing is used as the base material 11, the through-hole 13 is arrange | positioned regularly.

  As a material of the base material 11, what can be used in the to-be-processed liquid filtered using the filter 10 is used. The material of the base material 11 is preferably a metal so that the plating layer 3 or the plating layer 3 and the base layer 4 can be easily formed by using a plating process. For example, iron, nickel, copper, zinc, aluminum, and alloys thereof are preferably used as the metal used for the substrate 11. Among these, it is particularly preferable to use stainless steel that is excellent in corrosion resistance, low in cost, and easy to process as the material of the base material 11.

  The underlayer 4 is provided as necessary in order to improve the adhesion of the plating layer 3 to the base material 11. As a material used for the underlayer 4, for example, when the plating layer 3 made of a nickel alloy is formed on the surface of the substrate 11, it is preferable to use nickel or a nickel alloy. Examples of the nickel alloy include those containing one or more elements selected from boron, phosphorus, and zinc.

  The thickness of the foundation layer 4 is set to be equal to or greater than the thickness that can improve the adhesion of the plating layer 3 to the substrate 11. In addition, the thickness of the base layer 4 is set to a thickness in which the diameter of the through-hole 13 is in a range suitable for passing the liquid to be processed containing SS particles through the filter 10.

  As a metal or alloy used for the plating layer 3 formed of the plurality of fine structures 5, a metal or an alloy capable of depositing the plurality of fine structures 5 on the surface of the substrate 11 or the base layer 4 by a process such as electroplating. Use. Examples of such a metal include iron, nickel, copper, and alloys thereof. As the metal used for the plating layer 3, nickel or a nickel alloy is preferably used because it is a metal that can easily control the shape of the microstructure 5 and has excellent corrosion resistance. Examples of the nickel alloy include those containing one or more elements selected from boron, phosphorus, and zinc.

  The plating layer 3 is a composite in which a plurality of fine structures (needle-like structures) 5 are gathered on the surface of the base layer 4. In each microstructure 5, a base 5 a that is a region closer to the base material 11 than the base end 53 a of the microstructure 5 is integrated with a base 5 a of another adjacent microstructure 5. As a result, the base 5 a of the fine structure 5 is continuously formed on the surface of the underlayer 4.

  Between the adjacent fine structures 5, a trough 53 is formed whose width becomes narrower as the base end 53a is approached in a sectional view. The valley 53 is formed so as to surround each microstructure 5 in plan view. The valleys 53 that surround each microstructure 5 are formed so as to be connected to the valley 53 that surrounds another adjacent microstructure 5 in a plan view.

The number of the fine structures 5 per unit area (1 μm ² ) of the substrate 11 (formation density of the fine structures) is preferably 1.2 to 10.0 pieces / μm ² .
When the number of the fine structures 5 per unit area is 1.2 pieces / μm ² or more, the surface area of the filter 10 is sufficiently wide, and the SS particles are easily caught between the adjacent fine structures 5. For this reason, it can be set as the filter 10 in which SS particle | grains are easy to be capture | acquired by the mechanism of a deep layer filtration, and the cake 7 is easy to be formed with the captured SS particle | grains.
Therefore, the filter 10 has an excellent removal function capable of capturing the SS particles using the depth filtration mechanism and the cake filtration mechanism. The number of fine structures 5 per unit area is preferably 3.0 / μm ² or more in order to obtain a filter 10 having a higher SS particle removal function.

When the number of the fine structures 5 per unit area is 10.0 pieces / μm ² or less, the space between the adjacent fine structures 5 is prevented from becoming too narrow. For this reason, SS particle | grains are easily removed from the fine structure 5 by wash | cleaning.
Further, when the number of the fine structures 5 per unit area is 10.0 pieces / μm ² or less, as shown in FIG. 3, the valleys 53 formed between the adjacent fine structures 5 and the plating layer A sufficiently large space 31 surrounded by the cake 7 formed on the surface 3 is formed. The space 31 functions as a flow path through which the cake-filtered processing liquid flows when the cake 7 is formed. For this reason, compared with the filter which does not have the fine structure 5, since the area where the process liquid which passed the cake 7 is obtained becomes large, the filtration flow rate can be enlarged. Therefore, the filter 10 is easy to remove SS particles and has a large filtration flow rate. The number of fine structures 5 per unit area is preferably 7.0 pieces / μm ² or less in order to obtain an excellent filter 10 having a larger filtration flow rate.

The number of fine structures 5 (formation density of fine structures) per unit area (1 μm ² ) of the base material 11 when the fine structures 5 are needle-shaped structures is measured by the method shown below. is there.
The filter is observed with an electron microscope, and the number of apexes of a needle-like structure existing in a square having a length of 2 μm, a width of 2 μm, and an area of 4 μm ² is measured at four points (see FIG. 4). Then, the number of apexes of the needle-like structures measured at four locations is averaged, and the number of needle-like structures per unit area (1 μm ² ) is calculated.

The number of the fine structures 5 per unit length (1 μm) in the cross section of the substrate 11 (the number of fine structures formed per unit length) is preferably 1.0 to 4.0 pieces / μm.
When the number of the fine structures 5 per unit length is 1.0 / μm or more, as in the case where the number of the fine structures 5 per unit area is 1.2 / μm ² or more. In addition, an excellent removal function capable of capturing the SS particles using the mechanism of the depth filtration and the mechanism of the cake filtration is obtained. The number of the fine structures 5 per unit length is preferably 1.5 / μm or more in order to obtain a filter 10 having a higher function of removing SS particles.

When the number of the fine structures 5 per unit length is 4.0 pieces / μm or less, similarly to the case where the number of the fine structures 5 per unit area is 10.0 pieces / μm ² or less. The space between the adjacent fine structures 5 is prevented from becoming too narrow. For this reason, a sufficiently wide space 31 surrounded by the valleys 53 formed between the adjacent microstructures 5 and the cake 7 formed on the plating layer 3 is formed, and the filtration is performed. The filter 10 having a large flow rate can be obtained. The number of the fine structures 5 per unit length is preferably 3.0 pieces / μm or less in order to obtain a filter 10 having a larger filtration flow rate.

The number of the fine structures 5 per unit length (1 μm) in the cross section of the substrate 11 is measured by the following method.
The filter 10 is fixed with an embedded resin and cut, and the cut surface is smoothed by ion milling and photographed using a scanning electron microscope (SEM). Thereafter, the number of needle-like microstructures per 10 μm is measured along the substantially extending direction of the surface of the substrate in the photograph of the photographed cross section of the substrate. Then, the number of fine structures per unit length (1 μm) is calculated from the measured number of fine structures 5.

In the present embodiment, the average height H and the average width D of the base end portion of the needle-like microstructure 5 in the cross section of the base material 11 are those obtained by measuring the dimensions of the following portions by the measurement method shown below. It is.
As shown in FIG. 3, valleys 53 are formed between adjacent fine structures 5 in the cross section of the base material 11. In the cross section of the base material 11, the base ends 53 a and 53 a that are the valley bottoms facing each other with the fine structure 5 interposed therebetween are connected by a straight line 51, and the length thereof is set to the width D 1 and D 2 of the base end portion of the fine structure 5. To do. The shortest distance between the tip 52 of the fine structure 5 and the straight line 51 is defined as the heights H1 and H2 of the fine structure 5.

  In the cross section of the base material 11, when the two fine structures 57 and 58 are integrated (a fine structure indicated by reference numeral 59 in FIG. 3), the dimensions of the following parts are set to the fine structures 57 and 58. The heights H3 and H4 of 58 and the widths D3 and D4 of the base ends of the fine structures 57 and 58 were used.

  First, the straight ends 54 connect the base ends 53a and 53a, which are the valley bottoms facing each other across the fine structure 59 in which the needle-like fine structures 57 and 58 are integrated. Next, a perpendicular line 56 is drawn from the bottom of the valley 55 between the two microstructures 57 and 58 toward the straight line 54. The distances from the intersection of the perpendicular 56 and the straight line 54 to the base ends 53a and 53a are defined as the widths D3 and D4 of the base ends of the fine structures 57 and 58, respectively.

  Further, the shortest distances between the tips 52a and 52b of the fine structures 57 and 58 and the straight line 54 are defined as heights H3 and H4 of the fine structures 57 and 58, respectively. In addition, when the length of the perpendicular 56 is less than 3/4 of both the heights H3 and H4 of the fine structures 57 and 58, it is regarded as two independent fine structures. Further, the criterion that the two fine structures 57 and 58 are integrated is a case other than the case where the two fine structures are regarded as independent.

  In order to measure the height of the needle-like fine structure 5 and the width of the proximal end portion of the fine structure 5, the filter 10 is fixed with embedded resin and cut, and the cut surface is polished by ion milling. Images are taken using a scanning electron microscope (SEM). Thereafter, a range of 10 μm in length along the substantially extending direction of the surface of the base material in an enlarged photograph of the cross section of the base material 11 taken as one measurement region, and all the above-described fine structures existing in the four measurement regions The height of the object 5 and the width of the base end are measured. The average value of the heights of the four fine structures 5 measured is defined as the average height H of the fine structures 5. Moreover, let the average value of the width | variety of the base end part of the four fine structures 5 measured be the average width D of the base end part of the fine structure 5. FIG.

  The coefficient of variation of the height of the needle-like microstructure 5 in the cross section of the base material 11 is preferably 0.15 to 0.50. The coefficient of variation is obtained by dividing the standard deviation of the height distribution of the fine structures 5 in the cross section of the base material 11 by the arithmetic average value of the heights of the fine structures 5.

When the coefficient of variation is in the range of 0.15 to 0.50, the filter 10 is further excellent in the function of removing SS particles and the detergency.
When the variation coefficient is 0.15 or more, the height variation of the fine structure 5 is sufficiently large. For this reason, when the liquid to be processed containing SS particles is passed through the filter 10, the flow of the liquid to be processed including SS particles on the surface of the filter 10 becomes complicated, and SS is formed on the fine structure 5 having a high height. Particles are easily caught. As a result, the SS particles are easily captured by the deep layer filtration mechanism, and the cake 7 is easily formed on the surface of the plating layer 3 starting from the SS particles caught on the fine structure 5 having a high height. The coefficient of variation is preferably 0.18 or more in order to make the filter 10 more easily trapping SS particles.

  If the coefficient of variation is 0.50 or less, the cake 7 formed on the surface of the plating layer 3 is supported by the microstructure 5 having a low height, and thus formed between the adjacent microstructures 5. The space 31 surrounded by the valley 53 and the cake 7 is easily secured. For this reason, after the cake 7 is formed by filtration, the treatment liquid subjected to cake filtration easily flows in the space 31, and the filtration flow rate increases. Therefore, the filter 10 has an excellent filtration flow rate as compared with a filter without a needle-like structure. The coefficient of variation is preferably 0.36 or less in order to make the filter 10 having a higher filtration flow rate.

  The aspect ratio H / D between the average width D and the average height H of the base end portion of the needle-like microstructure 5 in the cross section of the base material 11 is preferably 0.5 to 4.0. When the aspect ratio H / D is 0.5 or more, sufficient is surrounded by the valleys 53 formed between the adjacent needle-like microstructures 5 and the cake 7 formed on the plating layer 3. A space 31 having a height is formed. For this reason, after the cake 7 is formed by filtration, the cake-filtered treatment liquid easily flows in the space 31, and the filtration flow rate is excellent. The aspect ratio H / D is preferably 1.0 or more in order to obtain a filter 10 having a higher filtration flow rate.

  When the aspect ratio H / D is 4.0 or less, the microstructure 5 is excellent in strength, and thus the filter 10 is excellent in durability. The aspect ratio H / D is preferably 3.0 or less in order to make the filter 10 more excellent in durability.

  The average height H of the needle-like microstructure 5 in the cross section of the substrate 11 is preferably 0.2 to 2.5 μm. When the average height H of the fine structure 5 is 0.2 μm or more, the fine structure 5 is surrounded by the valleys 53 formed between the adjacent fine structures 5 and the cake 7 formed on the plating layer 3. A sufficiently high space 31 is formed. For this reason, after the cake is formed at the time of filtration, the cake-filtered processing liquid easily flows in the space 31, and the filtration flow rate is excellent. The average height H of the fine structure 5 is preferably 0.4 μm or more in order to obtain a filter 10 having a further excellent filtration flow rate.

  When the average height H of the needle-like microstructure 5 is 2.5 μm or less, the space between the adjacent microstructures 5 is prevented from becoming too narrow. For this reason, it becomes the filter 10 excellent in the filtration flow volume by which the space 31 was fully ensured. The average height H of the fine structure 5 is preferably 1.8 μm or less in order to obtain a filter 10 having a further excellent filtration flow rate.

When the filter 10 is viewed in plan on the primary surface 11a side, the aperture is a ratio [(the area of the through-hole 13 / the area of the entire primary surface 11a) × 100] of the through-hole 13 to the plane area of the entire primary surface 11a. The rate is preferably 0.46% or more and 63.0% or less.
When the fine structure 5 is a needle-like structure, when the porosity is 0.46% or more, it is easy to secure a filtration flow rate, and the liquid to be treated can be efficiently filtered. On the other hand, when the porosity is 63.0% or less, the filtration performance by cake filtration can be enhanced, and a high-quality treatment liquid from which SS particles are sufficiently removed can be obtained.

  When the fine structure 5 has a needle shape, the average pore diameter of the through holes 13 is preferably 0.5 μm or more and 20 μm or less. When the average hole diameter of the through holes 13 is 0.5 μm or more, it becomes easier to secure a filtration flow rate, and the liquid to be treated can be efficiently filtered. If the average pore diameter of the through-holes 13 is 20 μm or less, the cake 7 can be formed more easily, so that the filtration performance by cake filtration can be enhanced.

Next, a method for manufacturing the filter 10 when the fine structure 5 is a needle-like structure will be described.
First, the base material 11 which is twilled and made into a mesh shape is prepared. Next, the base layer 4 is formed on the surface of the base material 11 having the plurality of through holes 13, 13. As a plating process for forming the underlayer 4, a conventionally known method can be used. For example, when forming the foundation layer 4 on the surface of the base material 11 made of stainless steel before forming the microstructure 5 made of nickel or nickel alloy, electrolytic nickel plating treatment or electroless nickel plating treatment is used. The underlayer 4 made of nickel or a nickel alloy is preferably formed.

  Next, a plurality of fine structures 5 are deposited on the surface of the base material 11 provided with the base layer 4 by electroplating, and the base material 11 is covered with the plating layer 3. As the electroplating process for forming the plating layer 3, a conventionally known method can be used. For example, when the underlayer 4 and the plating layer 3 are made of nickel or a nickel alloy, an additive is added to the plating bath after the formation of the underlayer 4 to continuously perform electrolytic nickel plating treatment or electroless nickel plating. It is preferable to form the plating layer 3 using a treatment.

  In addition, as a method for depositing a fine structure only on a part of the surface of the base material 11 provided with the underlayer 4, for example, a portion where the fine structure is not deposited is masked using a known method and then electric The method of performing a plating process is mentioned. In addition, the portion where the fine structure is not deposited on a part of the surface of the base material 11 by performing the electroplating process under the condition that the fine precipitate is easily deposited on the primary surface side of the base material 11 provided with the base layer 4. May be formed.

  In the electroplating process for depositing a plurality of microstructures 5, the shape and size of the microstructures 5 can be changed by changing the type, concentration, and plating time of the additive added to the plating bath. Examples of the additive include ethylenediamine dihydrochloride and ethylenediamine (EDA).

After performing the plating process for forming the plating layer 3, heat treatment may be performed as necessary to promote crystallization of the plating layer 3.
Moreover, after performing the plating process for forming the plating layer 3, another metal or organic substance is used on the surface of the plating layer 3 to improve the durability of the filter, if necessary. A coating layer may be formed.

  In addition, the surface of the plating layer 3 can be modified to form a plurality of types of modified regions having different affinity with the liquid to be treated. Specifically, the modification treatment of the plating layer 3 includes a hydrophilic treatment and a hydrophobic treatment. By performing such modification treatment, the flow of the liquid to be treated on the surface of the plating layer 3 becomes more complicated, and the SS particles can be easily aggregated on the surface of the plating layer 3.

Next, the processing method which processes a to-be-processed liquid using the processing system 100 of this embodiment is demonstrated.
In the present embodiment, before starting the treatment of the liquid to be treated, the valve 107 is switched to connect the outflow pipe 108f and the return pipe 108b, and the communication between the treatment tank 102 and the sludge concentration tank 104 is shut off.
Next, a liquid to be processed such as water containing SS particles is introduced into the liquid tank 101 to be processed and stored. And the to-be-processed liquid in the to-be-processed liquid tank 101 is stirred with an agitator as needed.

  Next, the first processing step is performed. In the first processing step, the pump 106 is driven to pump the liquid to be processed from the liquid tank 101 to be supplied to the supply unit 141 of the processing tank 102 via the inflow pipe 108a. Then, a part of the liquid to be processed supplied from the supply unit 141 to the liquid region 102a to be processed flows into the filter 10 from the primary surface 11a side, flows out from the secondary surface 11b, and is filtered to become a processing liquid. The processing liquid generated through the filter 10 is supplied from the first discharge part 142 of the processing tank 102 to the processing liquid tank 103 through the processing liquid pipe 108e and stored.

  In addition, of the liquid to be processed that has been supplied to the liquid area 102a to be processed, the liquid to be processed that has not passed through the filter 10 is discharged from the second discharge unit 143 and is discharged through the outflow pipe 108f and the return pipe 108b. It is returned to the processing liquid tank 101. Therefore, in this embodiment, the liquid to be processed is filtered while being circulated between the liquid tank 101 and the processing tank 102.

Here, the filtration performance of the processing system 100 when the fine structure 5 of the filter 10 installed in the processing tank 102 is a needle-like structure will be described.
Since the filter 10 has a plurality of needle-like fine structures 5, the contact area between the filter 10 and the liquid to be treated containing SS particles is large. For this reason, when filtration of the liquid to be treated is started, SS particles adhering to the surface of the fine structure 5 by the surface filtration and deep layer filtration mechanisms are used as a starting point, and the SS particles are rapidly removed at a plurality of locations on the surface of the plating layer 3. Aggregates are formed.

  The formed aggregate grows and peels off by continuing filtration of the liquid to be treated containing SS particles to the filter 10 and moves toward the through hole 13 together with the liquid to be treated containing SS particles. The one or more aggregates that have moved to the through-hole 13 become a bridge-like cake 7 that blocks the through-hole 13. Therefore, a predetermined SS particle removal performance can be obtained in a short time after the start of filtration of the liquid to be treated. In the processing method of this embodiment, not only the surface filtration mechanism but also the depth filtration mechanism and the cake filtration mechanism can be used to remove small SS particles in the liquid to be treated. Therefore, excellent filtration performance can be obtained.

  As shown in FIG. 3, the filter 10 has valleys 53 between adjacent microstructures 5. The valley 53 becomes narrower as it approaches the base end 53a that is the bottom of the valley in a cross-sectional view. For this reason, the SS particles captured by the filter 10 are unlikely to enter the vicinity of the base end 53 a of the valley 53.

  Therefore, in the filter 10 in which the cake 7 is formed on the surface of the plating layer 3, a sufficiently large space 31 surrounded by the valley 53 and the cake 7 is formed as shown in FIG. After the space 31 is formed, the upper portion of the space 31 is covered with the lid formed of the cake 7 even if the supply of the liquid to be processed containing SS particles to the filter 10 is continued. , SS particles hardly enter the space 31. Therefore, even if filtration of the liquid to be treated containing SS particles to the filter 10 is continued, a filtration flow rate is ensured.

  In the present embodiment, the first processing step is performed while measuring the flow rate of the processing liquid passing through the processing liquid pipe 108 e with the flow meter 110. The measurement of the flow rate of the processing liquid passing through the processing liquid pipe 108e by the flow meter 110 may be performed continuously during the first processing step, or may be performed every predetermined time. The measurement result of the flow rate of the processing liquid measured by the flow meter 110 is sent to the control unit 120.

  When the first treatment step is continued, SS particles further accumulate on the cake 7 formed on the filter 10, and the filtration flow rate gradually decreases. In the present embodiment, the control unit 120 determines whether or not the filter 10 needs to be cleaned based on the measurement result of the flow rate of the processing liquid passing through the processing liquid pipe 108e output from the flow meter 110. Specifically, the control unit 120 determines whether or not the flow rate of the processing liquid passing through the processing liquid pipe 108e measured by the flow meter 110 is equal to or less than a threshold value. As a result, when the flow rate of the processing liquid is higher than the threshold value, it is determined that cleaning is unnecessary, and the first processing step is continued.

  On the other hand, if the control unit 120 determines that the flow rate of the processing liquid is equal to or less than the threshold value, it is determined that cleaning is necessary. When it is determined that cleaning is necessary, the control unit 120 controls the bubble generating device 109 and the valve 107 to switch from the first processing step to the cleaning step. Specifically, the bubble generating device 109 is driven to supply bubbles to the liquid to be processed passing through the inflow pipe 108a through the pipe 108c, and the valve 107 is switched to connect the outflow pipe 108f and the discharge pipe 108d. Communicate. As a result, the liquid to be processed (bubble-containing liquid to be processed) to which bubbles are supplied from the bubble generating device 109 is supplied to the supply unit 141, and a part of the liquid to be processed contained in the bubble-containing liquid to be processed is filtered. A cleaning step is performed in which the remaining portion is discharged from the second discharge portion 143 together with the solid content deposited on the filter 10. That is, in the cleaning step, the bubble-containing liquid to be treated supplied from the supply unit 141 to the primary surface 11a side (the liquid area 102a) of the filter 10 in the liquid area 102a to be treated is cleaned while the filter 10 is being washed. Filtered.

  The size of the bubbles contained in the bubble-containing liquid to be treated is preferably 1 to 100 μm, and more preferably 10 to 50 μm. When the size of the bubbles contained in the bubble-containing liquid to be processed is 1 μm or more, the collapse of the cake due to the bubbles colliding with the cake 7 is promoted. For this reason, the cleaning effect by including a bubble becomes remarkable and is preferable. In addition, when the size of the bubbles contained in the bubble-containing treatment liquid is 100 μm or less, the air bubbles are not too fast and the bubbles are uniformly dispersed in the bubble-containing treatment liquid. For this reason, the collapse of the cake 7 due to the collision of the bubbles becomes uniform, and the collapse of the cake is promoted.

  In the present embodiment, the size of the bubbles contained in the bubble-containing liquid to be treated means the diameter of the bubbles obtained when air is introduced into tap water under the same conditions as those for introducing air into the liquid to be treated. The conditions for introducing air into the liquid to be treated are the pressure and flow rate of air when air is introduced in an actual apparatus, and the pressure and flow rate of the liquid to be treated. Further, the diameter of the bubbles obtained when air is introduced into the tap water is the diameter at 25 ° C. and 1 atm. For example, the mode is the mode of the distribution obtained by laser diffraction.

Next, the cleaning property of the filter 10 when the fine structure 5 is a needle-like structure will be described.
When the cleaning process is performed when the fine structure 5 is a needle-like structure, the cake 7 formed on the filter 10 is pushed away by the bubble-containing liquid to be removed. At this time, in the space 31 (see FIG. 3) existing in the through hole 13 and on the primary surface 11a side of the filter 10, the cleaning liquid is viewed from multiple directions through the valleys 53 formed so as to surround each microstructure 5. Flows in. As a result, the cake 7 formed so as to cover at least a part of the upper portion of the valley 53 is pushed up by the bubble-containing liquid to be treated, and the peeling of the cake 7 is promoted. The fine structure 5 has a tapered shape from the proximal end 53 a toward the distal end 52. For this reason, the cake 7 pushed up by the bubble-containing liquid to be processed is easily peeled off from the filter 10 by the flow of the bubble-containing liquid to be processed that is about to pass through the processing tank 102.

  Moreover, in the present embodiment, the collapse of the cake 7 is promoted by the bubbles contained in the bubble-containing liquid to be treated colliding with the cake 7. When the cake 7 is collapsed, the bubble-containing liquid to be treated easily enters the collapsed portion of the cake 7, and further collapse of the cake 7 is promoted. Moreover, the collapsed cake 7 becomes SS particles and is easily washed away by the bubble-containing liquid to be treated. As a result, the cake 7 formed on the filter 10 is quickly removed, and a high cleaning effect is obtained.

  In the cleaning process, the bubble-containing treatment liquid supplied to the treatment liquid region 102a of the treatment tank 102 passes through the treatment liquid region 102a, thereby concentrating the treatment liquid containing the SS particles removed from the filter 10. Become a liquid. The concentrated liquid to be processed generated in the cleaning process is sent from the liquid area 102a to the concentrated sludge tank 104 through the outflow pipe 108f and the discharge pipe 108d.

  When the washing process is continued, the cake 7 and SS particles formed on the filter 10 are removed, and the filtration flow rate is gradually improved. In the present embodiment, the cleaning process is performed while the flow rate of the processing liquid passing through the processing liquid pipe 108 e is measured by the flow meter 110. The flow rate of the processing liquid passing through the processing liquid pipe 108e by the flow meter 110 may be continuously measured during the cleaning process, or may be performed every predetermined time.

  The measurement result of the flow rate of the processing liquid measured by the flow meter 110 is sent to the control unit 120. In the present embodiment, the control unit 120 determines whether or not the filter 10 needs to be cleaned based on the measurement result of the flow rate of the processing liquid passing through the processing liquid pipe 108e output from the flow meter 110. Specifically, the control unit 120 determines whether or not the flow rate of the processing liquid passing through the processing liquid pipe 108e measured by the flow meter 110 is equal to or less than a threshold value. As a result, when the flow rate of the processing liquid is equal to or less than the threshold value, it is determined that cleaning is necessary, and the cleaning process is continued.

On the other hand, when the flow rate of the processing liquid is above the threshold value, it is determined that cleaning is unnecessary. When it is determined that the cleaning is unnecessary, the control unit 120 controls the bubble generating device 109 and the valve 107 to switch from the cleaning process to the second processing process. Specifically, the operation of the bubble generating device 109 is stopped to stop the supply of bubbles to the liquid to be processed, and the valve 107 is switched so that the outflow pipe 108f and the return pipe 108b communicate with each other. The liquid tank 101 is circulated between the liquid tank 101 and the processing tank 102, and the communication between the processing tank 102 and the sludge concentration tank 104 is blocked. As a result, as in the first processing step, the liquid to be processed to which no bubbles are added is supplied to the supply unit 141, a part of the liquid to be processed is filtered by the filter 10, and the remaining part of the liquid to be processed is discharged to the second discharge unit. A second processing step of discharging from 143 is performed.
In the treatment method of the present embodiment, it is preferable to repeatedly perform the same washing step and second treatment step as necessary after the second treatment step, a plurality of times.

  In the processing system 100 according to the present embodiment, the control unit 120 determines whether or not the filter needs to be cleaned based on the output from the flow meter 110. Cleaning is performed by supplying the added liquid to be processed to the supply unit 141, filtering a part of the liquid to be processed through the filter 10, and discharging the remaining part of the liquid to be processed from the second discharge unit 143 together with the solid matter deposited on the filter 10. Is executed. Therefore, in the processing system 100 of this embodiment, it can filter, washing | cleaning the filter 10 by performing said washing | cleaning in a washing | cleaning process.

Therefore, according to this embodiment, filtration of a to-be-processed liquid can be continued not only at the time of a process process (the process process after the first and the 2nd time and later) but also at the time of a washing process. As a result, even if the cleaning process is performed, the operation rate does not decrease and the liquid to be processed can be processed efficiently.
Moreover, in the present embodiment, the filter 10 having the plurality of fine structures 5 is cleaned using the bubble-containing liquid to be processed, so that a high cleaning effect is obtained. For this reason, it is not necessary to use clear water for washing | cleaning of the filter 10, for example, when wash | cleaning the primary surface 11a of the filter 10 using the clear water which does not contain a bubble. In the present embodiment, the bubble-containing liquid to be processed is generated by the bubble generation device 109 only during the cleaning process. For example, the bubble-containing liquid to be processed is generated by the bubble generation device 109 in the processing step and filtered. Compared to the case, the processing cost is low, which is preferable.

  Further, the processing system 100 of the present embodiment includes the filter 10 having a plurality of microstructures 5 having a maximum outer dimension smaller than the average hole diameter of the through holes 13 on at least the surface on the primary surface 11a side into which the liquid to be processed flows. Therefore, by filtering the liquid to be treated with the filter 10, a high-quality treatment liquid from which SS particles have been sufficiently removed can be obtained.

  Next, an example in which the fine structure 5 has a polyhedral shape will be described with reference to FIGS. 5 and 6. 5 and 6 show SEM photographs (secondary electron image (SEI), 15.0 kV, 2000 times (FIG. 5), 5000 times (FIG. 6)) when the microstructure 5 has a polyhedral shape.

In the polyhedron-shaped microstructure 5, a plurality of polyhedrons are bonded to each other and share a part of the volume. Each of the polyhedral fine structures 5 has a plurality of vertices where three or more planes intersect. Each microstructure 5 has a different shape and a different size, as shown in FIGS. The fine structures 5 are densely formed on the surface of the base material 11 or the surface of the base layer 4 (see FIG. 3) formed on the base material 11. As a result, the portion corresponding to the side of the polyhedron shape faces an irregular direction.
As the material of the polyhedral fine structure 5, the same material as that used for the fine structure 5 formed of a needle-like structure can be used.

  The average maximum outer dimension of the polyhedral fine structure 5 is preferably 0.5 to 10 μm. When the average maximum outer dimension of the precipitate is within the above range, the SS particles in the liquid to be treated are easily caught. For this reason, the cake is easily formed by the SS particles captured by the filter 10. As a result, the filter 10 having a high function of removing the SS particles can be easily obtained by using the cake filtration mechanism.

When the average maximum outer dimension of the polyhedral fine structure 5 is less than 0.5 μm, the unevenness of the surface of the plating layer 3 is reduced, and the amount of liquid to be processed passing through the gaps between the polyhedral precipitates is reduced. As a result, the adhesion of SS particles to the plating layer 3 may be difficult to occur. The average maximum outer dimension of the polyhedral fine structure 5 is more preferably 2.0 μm or more.
Further, when the average maximum outer dimension of the polyhedral fine structure 5 exceeds 10 μm, the contact area between the plating layer 3 and the liquid to be treated containing SS particles is reduced, and adhesion of the SS particles to the plating layer 3 is reduced. It may be difficult to happen. The average maximum outer dimension of the polyhedral fine structure 5 is more preferably 8.0 μm or less.

The coefficient of variation of the average maximum outer dimension of the polyhedral microstructure 5 is preferably 0.15 to 0.50. When the variation coefficient is in the range of 0.15 to 0.50, the filter 10 is further excellent in the function of removing SS particles and the detergency. In the present embodiment, the coefficient of variation of the average maximum outer dimension of the polyhedral fine structure is the standard deviation of the maximum outer dimension of the fine structure 5 divided by the arithmetic average value of the maximum outer dimension of the fine structure 5. Means something.
When the coefficient of variation is less than 0.15, when the liquid to be treated containing SS particles is passed through the filter 10, the flow of the liquid to be treated containing SS particles on the surface of the filter 10 becomes monotonous and fine. SS particles are less likely to be captured by the structure 5. Further, when the coefficient of variation exceeds 0.50, it becomes difficult to obtain a function for supporting the cake 7 formed on the surface of the plating layer 3 by the fine structure 5 having a small outer dimension.

  When the variation coefficient is 0.15 or more, the variation in the external dimension of the fine structure 5 is sufficiently large. For this reason, when the liquid to be processed containing SS particles is passed through the filter 10, the flow of the liquid to be processed including SS particles on the surface of the filter 10 becomes complicated, and the fine structure 5 having a large external dimension has an SS. Particles are easily caught. As a result, the SS particles are easily captured by the mechanism of the deep layer filtration, and the cake 7 is easily formed on the surface of the plating layer 3 starting from the SS particles caught by the fine structure 5 having a large outer dimension. The coefficient of variation is preferably 0.18 or more in order to make the filter 10 more easily trapping SS particles.

The average maximum outer dimension of the polyhedral fine structure 5 is measured by the following measuring method.
An enlarged photograph of the filter 10 is taken using a scanning electron microscope (SEM), and image processing is performed. Specifically, the outer dimensions of the largest portion of the polyhedral fine structure 5 are measured by selecting ten representative locations for one photograph, and the average value is the average maximum outer shape. Defined as a dimension.

Next, a method for manufacturing the filter 10 when the fine structure 5 is a polyhedral structure will be described.
The filter 10 in the case where the fine structure 5 is a polyhedral structure is the same as the filter 10 in the case where the fine structure is a needle-like structure, except for the electroplating process conditions for depositing the fine structure. Can be manufactured. That is, the polyhedral structure shown in FIGS. 5 and 6 can be deposited by setting the electroplating treatment conditions to the conditions described in Non-Patent Document 2, for example. In the electroplating treatment for depositing the polyhedral structure, the shape and size of the polyhedral structure can be changed by changing the type, concentration, and plating time of the additive added to the plating bath. Examples of the additive include 2-butyne-1,4-diol.

Next, a processing method for processing a liquid to be processed using the processing system 100 having the filter 10 in which the fine structure 5 is a polyhedral structure will be described.
In this case, except for the filtration performance and cleanability of the filter 10, it is the same as the case where the fine structure 5 is the above-described needle-like structure, and thus the description of the same part is omitted.

  Since the filter 10 in the case where the fine structure 5 is a polyhedral structure has a plurality of polyhedral structures, the contact area between the filter 10 and the liquid to be treated containing SS particles is large. For this reason, when the passage of the liquid to be treated is started, SS particles adhere to the surface of the polyhedral structure, and aggregates of SS particles are quickly formed. Further, the formed agglomerate grows by continuing to filter the liquid to be treated, and becomes a cake 7 that blocks the through hole 13. Therefore, a predetermined SS particle removal performance can be obtained in a short time after the passage of the liquid to be treated is started. In the processing method of this embodiment, not only the surface filtration mechanism but also the depth filtration mechanism and the cake filtration mechanism can be used to remove small SS particles in the liquid to be treated. Therefore, excellent filtration performance can be obtained.

  Further, in the filter 10 in the case where the fine structure 5 is a polyhedral structure, when the cake 7 is formed, a space surrounded by the gap 7 formed between the adjacent polyhedral structures and the cake 7 is formed. The Since the upper part of the space is covered with the lid formed of the cake 7, even if the liquid to be treated is continuously filtered, the SS particles are difficult to enter the space. Therefore, even if filtration of the liquid to be treated containing SS particles to the filter 10 is continued, a filtration flow rate is ensured.

  Even when the processing system 100 having the filter 10 in which the fine structure 5 is a polyhedral structure is used, in the cleaning process, a bubble-containing processing liquid containing bubbles is generated in the inflow pipe 108a. It supplies to the to-be-processed liquid area | region 102a of the processing tank 102. FIG.

  Even when the fine structure 5 is a polyhedral structure, the size of the bubbles contained in the bubble-containing liquid to be treated is preferably 1 to 100 μm, and more preferably 10 to 50 μm. When the size of the bubbles contained in the bubble-containing liquid to be processed is 1 μm or more, the collapse of the cake due to the bubbles colliding with the cake 7 is promoted. For this reason, the cleaning effect by including a bubble becomes remarkable and is preferable. In addition, when the size of the bubbles contained in the bubble-containing treatment liquid is 100 μm or less, the air bubbles are not too fast and the bubbles are uniformly dispersed in the bubble-containing treatment liquid. For this reason, the collapse of the cake 7 due to the collision of the bubbles becomes uniform, and the collapse of the cake is promoted.

  When the cleaning process is performed when the fine structure 5 is a polyhedral structure, the cake 7 formed on the filter 10 is pushed away by the bubble-containing liquid to be removed. At this time, the cleaning liquid flows from multiple directions into the spaces existing in the through holes 13 and on the primary surface 11 a side of the filter 10 through valleys formed so as to surround each microstructure 5. As a result, the cake 7 formed so as to cover at least a part of the upper part of the valley is pushed up by the bubble-containing liquid to be treated, and the peeling of the cake 7 is promoted.

  Moreover, in the present embodiment, the collapse of the cake 7 is promoted by the bubbles contained in the bubble-containing liquid to be treated colliding with the cake 7. When the cake 7 is collapsed, the bubble-containing liquid to be treated easily enters the collapsed portion of the cake 7, and further collapse of the cake 7 is promoted. Moreover, the collapsed cake 7 becomes SS particles and is easily washed away by the bubble-containing liquid to be treated. As a result, the cake 7 formed on the filter 10 is quickly removed, and a high cleaning effect is obtained.

In the processing system of the present embodiment, even when the fine structure 5 is a polyhedral structure, the control unit 120 determines whether or not the filter needs to be cleaned based on the output from the flow meter 110 and needs to be cleaned. When the determination is made, the liquid to be processed to which bubbles are added by the bubble generating device 109 is supplied to the supply unit 141, a part of the liquid to be processed is filtered by the filter 10, and the remaining part of the liquid to be processed is deposited on the filter 10. The cleaning to be discharged from the second discharge unit 143 together with the solid content is performed. Therefore, it can filter, washing | cleaning the filter 10 by performing said washing | cleaning in a washing | cleaning process. Therefore, filtration of a to-be-processed liquid can be continued not only at the time of a process process but at the time of a washing process.
Even when the fine structure 5 is a polyhedral structure, the filter 10 is cleaned using the bubble-containing liquid to be processed, so that a high cleaning effect is obtained.
Even when the fine structure 5 is a polyhedral structure, a high-quality treatment liquid from which SS particles are sufficiently removed can be obtained by filtering the treatment liquid with the filter 10.

(Second Embodiment)
FIG. 7 is a schematic diagram illustrating a processing system according to the second embodiment.
The processing system 100A shown in FIG. 7 includes a liquid tank 101 to be processed, a processing tank 102A, a pump 106, a bubble generator 109, a processing liquid tank 103, a concentrated sludge tank 104, and a pipe connecting them. Have. The processing system 100A shown in FIG. 2 is of a cross flow type in which the liquid to be processed is filtered through the filter 10 while flowing in parallel with the surface of the filter 10 on the side of the liquid area 102a to be processed.
In the processing system 100A shown in FIG. 7, the same members as those in the processing system 100 shown in FIG.

  The processing tank 102A has a cylindrical outer shape extending in a substantially horizontal direction. The filter 10 installed in the processing tank 102A is formed by forming the filter 10 installed in the processing system 100 shown in FIG. 1 into a cylindrical shape. In the processing system 100A shown in FIG. 7, the central axis direction of the cylindrical filter 10 and the central axis direction of the cylindrical processing tank 102A are substantially the same.

  Further, in the processing system 100A shown in FIG. 7, the inner side of the filter 10 is the primary surface 11a side into which the liquid to be processed flows, and the outer side of the filter 10 is the secondary surface 11b side from which the liquid to be processed flows out. The inside of the processing tank 102 </ b> A is divided into an inner side and an outer side of the cylindrical filter 10. The inside of the filter 10 is a processing liquid region 102a, and the outside of the filter 10 is a processing liquid region 102b.

  The treatment tank 102A is provided with a first supply part 141a to which the processing pipe 108h is connected and a second supply part 141b to which the cleaning pipe 108g is connected as supply parts to which the liquid to be treated is supplied. Yes. The first supply unit 141a and the second supply unit 141b are formed on one end surface of the two end surfaces of the cylindrical treatment tank 102A. The 1st supply part 141a is arrange | positioned in the filter 10 vicinity in the inside of the filter 10 which is in contact with one end surface. The 2nd supply part 141b is arrange | positioned in the position of the approximate center axis | shaft of the filter 10 which is in contact with one end surface.

Further, the treatment tank 102A is provided with a second discharge part 143 for discharging a part of the liquid to be processed supplied to the supply part. The 2nd discharge part 143 is formed in the other end surface on the opposite side to the end surface in which the 1st supply part 141a is provided among the two end surfaces of the cylindrical processing tank 102A. The 2nd discharge part 143 is arrange | positioned in the position of the approximate center axis | shaft of the filter 10 which is in contact with the other end surface.
A first discharge part 142 for discharging the processing liquid that has passed through the filter 10 is formed at the lower part of the side surface of the processing tank 102A.

  The 2nd supply part 141b may be formed in the end surface by which the 2nd discharge part 143 is not provided among the two end surfaces of the cylindrical processing tank 102A, or the 2nd discharge part 143 is provided. It may be formed on the end surface on the side. Since the liquid to be processed is supplied from the second supply unit 141b via a cleaning nozzle 121, which will be described later, it is supplied via the cleaning nozzle 121 regardless of the distance between the second supply unit 141b and the second discharge unit 143. The liquid to be treated and the filter 10 can be sufficiently brought into contact with each other.

  A cleaning nozzle 121 is installed in the processing target liquid region 102a of the processing tank 102A. The cleaning nozzle 121 ejects a liquid to be processed (bubble-containing liquid to be processed) to which bubbles are added toward the primary surface 11 a of the filter 10. The cleaning nozzle 121 has a cylindrical main body 121b sealed at one end, and a plurality of jet nozzles 121a and 121a that discharge the bubble-containing liquid to be processed from the main body 121b toward the outer peripheral direction. The end of the main body 121b on the unsealed side is connected to the second supply unit 141b.

The outer diameter of the main body 121 b of the cleaning nozzle 121 is smaller than the inner diameter of the cylindrical filter 10. The cleaning nozzle 121 is installed so that the central axis direction of the main body 121b is substantially the same as the central axis direction of the filter 10 and the processing tank 102A.
The spout 121a is formed at regular intervals in the length direction and the circumferential direction of the main body 121b. The inner diameter of the ejection port 121a is preferably larger than the size of the bubbles contained in the bubble-containing treatment liquid so that the cleaning effect due to the bubble-containing treatment liquid containing bubbles is sufficiently obtained. The shape of the jet nozzle 121a is not particularly limited. When the shape of the ejection port 121a is not circular in plan view, the inner diameter of the ejection port 121a means the diameter of the inscribed circle of the ejection port 121a.

In the processing system 100A shown in FIG. 7, the inflow pipe 108a is connected to the liquid tank 101 to be processed, the cleaning pipe 108g branched from the inflow pipe 108a, and the processing pipe 108h.
The processing pipe 108h is connected or disconnected from the first supply unit 141a by switching the valve 107a.
A bubble generating device 109 is connected to the cleaning pipe 108g through a pipe 108c. The cleaning pipe 108g is connected to or disconnected from the cleaning nozzle 121 via the second supply unit 141b by switching the valve 107b.

  Based on the output from the flow meter 110 (detection means), the control unit 120 determines whether or not the filter 10 needs to be cleaned. If it is determined that cleaning is necessary, the control unit 120 executes cleaning and determines that cleaning is not necessary. In some cases, the process is executed. In the present embodiment, the control unit 120 determines whether or not the filter 10 needs to be cleaned depending on whether or not the measurement result of the flow rate of the processing liquid sent from the flow meter 110 is equal to or less than a predetermined threshold value. Thus, the bubble generating device 109 and the valves 107, 107a, 107b are controlled.

  When the control unit 120 determines that the cleaning is unnecessary, the control unit 120 controls the bubble generation device 109 and the valves 107, 107a, and 107b so that the bubble generation device 109 is stopped and the valve 107 is stopped. 107a and 107b are switched to communicate the outflow pipe 108f and the discharge pipe 108d, and the inflow pipe 108a and the first supply unit 141a are communicated through the processing pipe 108h. As a result, the processing liquid that does not add bubbles is supplied to the first supply unit 141a, a part of the processing liquid is filtered by the filter 10, and the remaining part of the processing liquid is discharged from the second discharge unit 143. Let it run.

  When the control unit 120 determines that cleaning is necessary, the control unit 120 controls the bubble generation device 109 and the valves 107, 107a, and 107b to drive the bubble generation device 109, and the valves 107, 107a, 107b is switched to connect the outflow pipe 108f and the discharge pipe 108d, and the inflow pipe 108a and the second supply unit 141b are connected to each other through the cleaning pipe 108g. As a result, the liquid to be treated (bubble-containing liquid to be treated) supplied with bubbles supplied from the bubble generating device 109 is supplied to the second supply unit 141b, and a part of the liquid to be treated contained in the liquid containing bubbles is treated. The filter 10 is filtered, and the remaining part is washed with the solid content deposited on the filter 10 to be discharged from the second discharge part 143.

Next, a processing method for processing a liquid to be processed using the processing system 100A of the present embodiment will be described.
In the present embodiment, before the processing of the liquid to be processed is started, the inlet pipe 108a and the first supply part 141a are connected by switching the valve 107a. Moreover, the inflow piping 108a and the 2nd supply part 141b are interrupted | blocked by switching the valve 107b. Further, by switching the valve 107, the outflow pipe 108f and the return pipe 108b are connected, and the communication between the treatment tank 102A and the sludge concentration tank 104 is blocked.

Thereafter, the first processing step is performed in the same manner as in the case of processing the liquid to be processed using the processing system 100 of the first embodiment.
As in the first embodiment, the control unit 120 determines whether the filter 10 needs to be cleaned based on the measurement result of the flow rate of the processing liquid passing through the processing liquid pipe 108e output from the flow meter 110. To do. As a result, when the flow rate of the processing liquid is higher than the threshold value, it is determined that cleaning is unnecessary, and the first processing step is continued.

  On the other hand, when the flow rate of the processing liquid is equal to or less than the threshold value, it is determined that cleaning is necessary. When it is determined that the cleaning is necessary, the control unit 120 controls the bubble generation device 109 and the valves 107, 107a, 107b to switch from the first processing step to the cleaning step. Specifically, the bubble generating device 109 is driven to supply bubbles to the liquid to be processed passing through the cleaning pipe 108g via the pipe 108c, and the inflow pipe 108a and the second supply unit 141b are connected to the cleaning pipe. The inflow piping 108a and the 1st supply part 141a are interrupted | blocked through 108g, and the outflow piping 108f and the discharge piping 108d are connected.

  As a result, the liquid to be processed (bubble-containing liquid to be processed) to which bubbles are supplied from the bubble generation device 109 is supplied to the second supply unit 141b, and toward the primary surface 11a of the filter 10 through the cleaning nozzle 121. Erupt. Then, a cleaning process is performed in which a part of the liquid to be processed contained in the bubble-containing liquid to be processed is filtered by the filter 10 and the remaining part is discharged from the second discharge part 143 together with the solid content deposited on the filter 10. That is, in the cleaning process, the bubble-containing liquid to be treated supplied to the primary surface 11a side (the liquid area 102a) of the filter 10 in the liquid area 102a of the treatment tank 102A is washed with the filter 10 while washing the filter 10. Filtered.

  In the present embodiment, in the cleaning process, the bubble-containing liquid is ejected from the plurality of ejection ports 121a of the cleaning nozzle 121, so that the bubble-containing coating is substantially perpendicular to the extending direction of the primary surface 11a of the filter 10. Treatment liquid is supplied. As a result, the decay of the cake 7 is promoted, the cake 7 formed on the filter 10 is quickly removed, and a high cleaning effect is obtained.

  Also in the present embodiment, as in the first embodiment, the cleaning process is performed while the flow rate of the processing liquid passing through the processing liquid pipe 108e is measured by the flow meter 110. As in the first embodiment, the control unit 120 determines whether the filter 10 needs to be cleaned based on the measurement result of the flow rate of the processing liquid passing through the processing liquid pipe 108e output from the flow meter 110. To do. As a result, when the flow rate of the processing liquid is equal to or less than the threshold value, it is determined that cleaning is necessary, and the cleaning process is continued.

  On the other hand, when the flow rate of the processing liquid is above the threshold value, it is determined that cleaning is unnecessary. When it is determined that the cleaning is unnecessary, the control unit 120 controls the bubble generating device 109 and the valves 107, 107a, and 107b to switch from the cleaning process to the second processing process. Specifically, the operation of the bubble generation device 109 is stopped to stop the supply of bubbles to the liquid to be processed, and the valves 107, 107a, and 107b are switched to connect the outflow pipe 108f and the return pipe 108b. The pipe 108a and the first supply unit 141a are communicated with each other via the processing pipe 108h to circulate the liquid to be processed between the liquid tank 101 and the processing tank 102A, and the inflow pipe 108a and the second supply part 141b. And the communication between the treatment tank 102A and the sludge concentration tank 104 is blocked.

As a result, as in the first processing step, the liquid to be processed to which no bubbles are added is supplied to the first supply unit 141a, a part of the liquid to be processed is filtered by the filter 10, and the remaining part of the liquid to be processed is second A second processing step of discharging from the discharge unit 143 is performed.
In the treatment method of the present embodiment, it is preferable to repeatedly perform the same washing step and second treatment step as necessary after the second treatment step, a plurality of times.

  Also in the processing system 100A shown in FIG. 7, when the control unit 120 determines whether the filter needs to be cleaned based on the output from the flow meter 110 and determines that the filter needs to be cleaned, The liquid to be processed is supplied to the second supply unit 141 b, a part of the liquid to be processed is filtered by the filter 10, and the remaining part of the liquid to be processed is supplied from the second discharge unit 143 together with the solid content deposited on the filter 10. Perform cleaning to be discharged. Therefore, in the processing system 100A of the present embodiment, the filter 10 can be filtered while being washed by performing the above washing in the washing step. Therefore, the same effect as the first embodiment described above can be obtained.

In the processing system 100A shown in FIG. 7, the cleaning nozzle 121 is an example having a cylindrical main body 121b and a plurality of jet outlets 121a for jetting the bubble-containing liquid to be processed outward from the main body 121b. However, the cleaning nozzle 121 is not limited to the example shown in FIG.
FIG. 8 is an explanatory diagram for explaining a processing system in which another cleaning nozzle is installed in the processing tank. Since the processing system shown in FIG. 8 and the processing system 100A shown in FIG. 7 are the same except for the cleaning nozzle, the same members are denoted by the same reference numerals and description thereof is omitted.

The cleaning nozzle 122 shown in FIG. 8 ejects the bubble-containing liquid to be processed toward the primary surface 11 a of the filter 10. The cleaning nozzle 122 is arranged so that the direction of the bubble-containing liquid to be ejected is substantially tangential to the inner periphery of the filter 10.
Further, the outer diameter of the cleaning nozzle 122 is smaller than the inner diameter of the cylindrical filter 10. Further, the jet nozzle of the cleaning nozzle 122 may have an inner diameter larger than the size of the bubbles contained in the bubble-containing treatment liquid so that the cleaning effect due to the bubble-containing treatment liquid containing bubbles is sufficiently obtained. preferable.

  When the cleaning process is performed using the processing system having the cleaning nozzle 122 shown in FIG. 8, the swirl flow along the inner peripheral surface of the filter 10 is caused by supplying the bubble-containing liquid to be processed from the cleaning nozzle 122 to the filter 10. It is formed. As a result, the decay of the cake 7 is promoted, the cake 7 formed on the filter 10 and the SS particles adhering to the filter 10 are quickly removed, and a high cleaning effect is obtained.

In each said embodiment, although the filter 10 using the mesh-shaped thing was mentioned as an example and demonstrated as the base material 11, the base material 11 of the filter 10 is not limited to said example.
For example, you may use the filter which has a plate-shaped base material in which the several through-hole was formed as a base material.

FIG. 9 is an external perspective view showing another example of the filter. FIG. 10 is a cross-sectional view of the filter shown in FIG. 9 when viewed from the end face side.
The plate-like base material 211 included in the filter 212 is formed of the same material as the mesh-like base material 11 in each of the above embodiments. Hereinafter, in the description of the filter 212, the description of the same configuration as the filter 10 in each of the above embodiments is omitted.

  A plurality of through holes 213, 213... Penetrating in the thickness direction are formed in the plate-like base material 211. The through holes 213, 213,... Are cylindrical holes that connect the primary surface 211a and the secondary surface 211b of the base material 211. The through holes 213, 213,... Are arranged in a staggered arrangement along the primary surface 211a.

The average hole diameter of the through holes 213 is preferably 1 μm to 5 mm. When the average pore diameter of the through holes 213, 213... Is 1 μm or more, it becomes easy to secure a filtration flow rate in the treatment system having the filter 212, and the liquid to be treated can be efficiently filtered. When the average hole diameter of the through holes 213, 213,... Is 5 mm or less, the cake is easily formed. Therefore, the filtration performance by cake filtration can be improved, and a high-quality treatment liquid from which SS particles are sufficiently removed can be obtained. can get.
The average hole diameter of the through holes 213, 213,... Means the average value of the diameters of the inscribed circles of the plurality of through holes 213, 213,.

  A plurality of fine structures 205 are formed on the entire surface of the filter 212. That is, the fine structure 205 is formed so as to cover the primary surface (inflow surface) 211a of the filter 212, the secondary surface (outflow surface) 211b through which the liquid to be processed flows out, and the inner wall surface of the through hole 213. Yes. As the fine structure 205, the needle-like structure or the polyhedral structure in each of the above embodiments is formed. The fine structure 205 has a maximum outer dimension smaller than the average hole diameter of the through holes 213.

  The filter 212 shown in FIG. 9 can be manufactured in the same manner as the filter 10 in each of the above embodiments, except that the base material 211 is used instead of the base material 11 of the filter 10 in each of the above embodiments.

  In the filter 212 shown in FIGS. 9 and 10, the primary surface 211a side into which the liquid to be processed flows is a flat surface, and a plurality of fine structures 205 are formed. Therefore, the liquid pressure when the liquid to be treated flows into the filter 212 becomes uniform, and the liquid pressure does not concentrate locally on the surface of the filter 212. For this reason, in the filter 212 shown in FIG. 9, the durability of the filter 212 against the liquid pressure when the liquid to be treated is introduced is enhanced, and the formation of cake is promoted.

In the filter 212 shown in FIG. 9, the through holes 213 having a circular shape in plan view are arranged on the base material 211 so as to form a staggered arrangement, but the shape and arrangement of the individual through holes are not limited.
11 to 13 are schematic plan views illustrating other examples of the filter. In the filter 291 shown in FIG. 11, the through holes 292 having a rectangular planar shape are arranged at regular intervals in a lattice shape. In the filter 294 shown in FIG. 12, the through holes 295 having a rectangular planar shape are formed in a staggered arrangement. In the filter 297 shown in FIG. 13, the through holes 298 having a hexagonal plan shape are formed in a staggered arrangement.

In addition to this, the planar shape of the through-hole formed in the base material can be various shapes such as a polygonal shape such as a triangle and a pentagon, an elliptical shape, and a cross shape, and is not particularly limited.
Further, regarding the arrangement form of the plurality of through holes, for example, the filters 291 shown in FIG. 11 may be equally arranged, or the filters 212, 294, and 297 shown in FIGS. 9, 12, and 13 may be used. Like this, it may be a staggered arrangement, or may be arranged at random, and is not particularly limited.
The average hole diameter of the through holes having these planar shapes means an average value of the diameters of the inscribed circles of the plurality of through holes penetrating the filter.

  Similar to the filter 212 shown in FIG. 9, a plurality of fine structures 205 are formed on the entire surface of the filters 291, 294, and 297. As the fine structure 205, the needle-like structure or the polyhedral structure in each of the above embodiments is formed. The fine structure 205 has a maximum outer dimension smaller than the average hole diameter of the through holes 213.

  The filters 212, 291, 294, and 297 shown in FIG. 9 to FIG. 13 may be used in the form of a plate, or may be formed in a cylindrical shape, for example.

  Further, as a base material, it has a filter body in which wire rods are arranged in a planar shape, and a support member that supports the wire rod, and a gap is formed between the wire rods adjacent to each other. The wire rod facing the primary surface into which the liquid to be treated flows may be a filter having a flat substrate.

FIG. 14 is a schematic view showing another example of a filter formed in a cylindrical shape. 15 is a cross-sectional view of the filter shown in FIG. 14 when viewed from the end surface side. 16 is an enlarged cross-sectional view of a main part showing the inner peripheral surface side of the filter shown in FIG.
A base material 310 included in the filter 300 shown in FIG. 14 is formed of the same material as the mesh base material 11 in each of the above embodiments. Hereinafter, in the description of the filter 300, the description of the same configuration as the filter 10 in each of the above embodiments is omitted.

  The substrate 310 of the filter 300 is formed of a filter body 312 in which the wire materials 311 are arranged in a planar shape, and a support member 313 that supports the wire material 311. The filter body 312 is formed by winding a long wire 311 into a coil shape and forming it into a hollow cylindrical body.

  The wire 311 has a triangular cross section perpendicular to the extending direction. The wire 311 is supported by the support member 313 so as to be separated from each other while maintaining a gap having a predetermined width between adjacent wires. Thus, a slit-shaped gap 316 is formed in the cylindrical filter body 312 so as to penetrate between the inner peripheral surface 312a and the outer peripheral surface 312b.

  The support member 313 is a wire having a square cross section. The support member 313 is joined to the wire 311 on the outer peripheral surface 312 b side of the filter body 312. For example, four support members 313 are formed at equal intervals along the circumferential direction of the wire 311. The support member 313 extends in parallel to the central axis of the filter body 312 and supports the wound wire 311 from the outer peripheral surface 312b side. The support member 313 and the wire 311 are joined by, for example, sintering.

  The wire 311 facing the inner peripheral surface 312a side of the filter body 312 has a flat surface 311f. That is, one side of the triangle of the wire 311 having a triangular cross-sectional shape is arranged along the inner peripheral surface 312a. The wire 311 is joined to the support member 313 at the apex of the triangle facing one side of the triangle along the inner peripheral surface 312a of the wire 311.

  In the filter 300 shown in FIG. 14, the liquid to be treated is introduced toward the inner peripheral surface 312 a of the filter body 312, the liquid to be treated is filtered through the gap 316, and the treated water after filtration is filtered from the outer peripheral surface 312 b. Spill. The gaps 316 between the wire rods 311 and 311 adjacent to each other with different circulations are formed by using the wire rod 311 having a triangular cross-sectional shape, so that the outer periphery from which the processing liquid flows out from the inner peripheral surface (primary surface) 312a side into which the liquid to be processed flows. It is formed so that the width increases toward the surface (secondary surface) 312b side.

  In the filter 300 shown in FIG. 14, the average hole diameter of the through holes means the average distance of the narrowest portion in the gap 316 between the wire rods 311. In other words, the average hole diameter of the through holes in the filter 300 means a distance between adjacent flat surfaces 311f facing the inner peripheral surface 312a.

In the filter 300, a plurality of fine structures 305 are formed on the inner peripheral surface 312a side into which the liquid to be treated flows (in other words, on the flat surface 311f (see FIG. 16) of the wire 311 facing the inner peripheral surface 312a). Yes. As the plurality of fine structures 305 included in the filter 300, the needle-like structure or the polyhedron structure in each of the above embodiments is formed. The fine structure 305 has a maximum outer dimension smaller than the average hole diameter of the through holes.
The fine structure 305 may be formed on the entire surface of the filter 300.

  The filter 300 shown in FIG. 14 uses a base material 310 in which a wire 311 wound in a coil shape and a support member 313 are combined by sintering instead of the base material 11 of the filter 10 in each of the above embodiments. Can be manufactured in the same manner as the filter 10 in each of the above embodiments.

  In the filter 300 shown in FIG. 14, a plurality of fine structures 305 are formed on the flat surface 311f of the wire 311 constituting the inner peripheral surface 312a into which the liquid to be processed flows. Therefore, the liquid pressure to the filter 300 at the time of inflow of the liquid to be treated becomes uniform, and the liquid pressure does not concentrate locally on the surface of the filter 300. For this reason, in the filter 300 shown in FIG. 14, the durability of the filter 300 with respect to the hydraulic pressure at the time of inflow of the liquid to be treated is enhanced, and the formation of cake is promoted.

In the filter 300 illustrated in FIG. 14, an example in which a wire having a triangular cross section is used. However, the cross sectional shape of the wire is not limited to a triangle, and may be, for example, a trapezoid.
FIG. 17 is an enlarged cross-sectional view of the main part showing the inner peripheral surface side in another example of the filter. A filter 370 shown in FIG. 17 includes a filter body 372 in which a wire 371 having a trapezoidal cross-sectional shape perpendicular to the extending direction is wound in a coil shape to form a hollow cylindrical body. The wire 371 is supported by the support member 373 on the outer peripheral surface 372b side so as to be separated with a gap 376 having a predetermined width between adjacent wire members 371.

  In the filter 370 shown in FIG. 17, the inner peripheral surface 372a of the filter body 372 is a primary surface into which the liquid to be treated flows, and the outer peripheral surface 372b is a secondary surface from which the treated water filtered by the filter body 372 flows out. Is done. Of the filter 372, the wire 371 facing the inner peripheral surface 372a has a flat surface 371f. The wire 371 having a trapezoidal cross-sectional shape is arranged so that one of the longer parallel sides of the trapezoid is along the inner peripheral surface 372a, and the shorter one of the two parallel sides is joined to the support member 313. ing.

  In the filter 370, a plurality of fine structures 305 are formed on the flat inner peripheral surface 372a side into which the liquid to be processed flows and the inner surface of the gap 376. The fine structure 305 is only required to be formed on the inner peripheral surface 372a (primary surface) side of the filter body 372, and may be formed on the entire surface of the filter 370.

In the filters 300 and 370 shown in FIG. 14 and FIG. 17, an example in which the wire is wound into a coil shape to form a hollow cylindrical body is shown. However, a plurality of wires may be arranged on one surface to form a flat plate shape. Good. FIG. 18 is an external perspective view showing another example of the filter.
A filter 390 illustrated in FIG. 18 includes a filter body 392 in which a plurality of wire rods 391 are arranged in a planar shape and a support member 393 that supports the wire rod 391 as a base material. The filter body 392 is formed by arranging a plurality of wire rods 391 having a triangular cross-sectional shape perpendicular to the extending direction on a flat surface and forming it into a flat plate shape.

  The wire 391 is fixed to the support member 393 so as to maintain a slit-shaped gap 396 having a predetermined width between the adjacent wires 391 and 391. In the filter 390, the wire 391 that faces the one surface 392a that is the upper side in FIG. 18 forms a flat surface 391f. In the case of a wire rod 391 having a triangular cross-sectional shape, one side of the triangle is disposed along one surface 392a, and is joined to the support member 393 at the apex of the triangle facing this one side.

  The support member 393 is made of, for example, a wire having a rectangular or triangular cross section, and is joined to the wire 391 on the other surface 392b side of the filter body 392. The support member 393 extends along the arrangement direction of the wires 391 and is joined to the plurality of wires 391. The support member 393 and the wire 391 are joined by, for example, sintering.

In the filter 390, the liquid to be treated is introduced from the upper surface (primary surface) 392a side in FIG. 18, and the treated water after filtration is discharged from the other surface (secondary surface) 392b.
In the filter 390, a plurality of fine structures 305 are formed on a flat surface 392a into which the liquid to be processed flows. The fine structure 305 only needs to be formed on the one surface 392a (primary surface) side of the filter body 392, and may be formed on the entire surface of the filter 390.

In the filters 300, 370, and 390 shown in FIG. 14, FIG. 17, and FIG. 18, the example in the case where a gap is formed between adjacent wires by the support member that supports the wire has been shown. It is also possible to use adjacent wires to separate them while maintaining a gap of a predetermined width.
FIG. 19 is an external perspective view showing another example of the filter.

A filter 90 shown in FIG. 19 includes, as a base material, a filter body 92 in which a plurality of wire rods 91 are arranged on a plane and formed into a flat plate shape, and a support member 93 that supports the wire rod 91.
The wire 91 has a rectangular cross section, and convex portions 95 are formed at predetermined intervals on one side of the rectangle. The convex portion is configured to separate adjacent wire rods 91 while maintaining a gap having a predetermined width. For example, when the filter body 92 is viewed in plan, the convex portions 95 are formed by shifting the positions of the adjacent wire rods 91 so as to form a staggered arrangement along the arrangement direction of the wire rods 91.

In the flat filter body 92 of the filter 90 shown in FIG. 19, a slit-like gap 96 penetrating between the one surface 92 a and the other surface 92 b is formed by the convex portion 95 formed on the wire 91.
In the filter 90 shown in FIG. 19, the average hole diameter of the through holes means an average distance of the gaps 96 between the wire rods 91.

  The support member 93 is, for example, a wire having a rectangular or triangular cross section (rectangular in FIG. 19). The support member 93 is formed, for example, so as to extend along the arrangement direction of the wires 91. The support member 93 is joined to the plurality of wires 91 on the other surface 92 b side of the filter body 92. The support member 93 and the wire 91 are joined by, for example, sintering.

In the base material of the filter 90 shown in FIG. 19, the filter body 92 and the support member 93 in FIG. 19 are formed of the same material as the mesh base material 11 in each of the above embodiments.
In the filter 90, a plurality of fine structures 305 are formed on the one surface (primary surface) 92 a side into which the liquid to be treated flows and the inner surface of the gap 96. As the plurality of fine structures 305 included in the filter 90, the needle-like structure or the polyhedral structure in each of the above embodiments is formed. The fine structure 305 has a maximum outer dimension smaller than the average hole diameter of the through holes.
The fine structure 305 may be formed on the entire surface of the filter 90.

A filter 90 shown in FIG. 19 is a filter in each of the above embodiments except that instead of the base material 11 of the filter 10 in each of the above embodiments, a support member 93 and a wire 91 are sintered and combined. 10 can be produced in the same manner.
The filter 90 shown in FIG. 19 may be used in the form of a plate, or may be used in the form of a cylinder, for example.

  The treatment system (treatment device) and treatment method of each of the embodiments described above are suitable for treating the treatment water as the treatment liquid, but the treatment system and treatment method of the embodiment are treatments for treating the treatment water. It is not limited to the system and the processing method.

In each of the above embodiments, the case where a flow meter is used as the detection means for detecting the filtration performance of the filter has been described as an example. However, the present invention is not limited to the flow meter, and for example, a pressure gauge may be used. .
Next, as an example of the case where a pressure gauge is used as the detection means, in the processing system 100 shown in FIG. 1, a pressure gauge for measuring the pressure of the liquid to be processed supplied from the supply unit 141 to the liquid area to be processed 102a is provided. An example will be described.
The position of the pressure gauge is not limited as long as the pressure of the liquid to be processed supplied from the supply unit 141 to the liquid region to be processed 102a can be measured, and an arbitrary position on the supply unit 141 side than the connection part with the pipe 108c in the inflow pipe 108a. Can be installed at a position.

  As the pressure gauge, a pressure gauge that continuously measures the pressure of the liquid to be processed supplied from the supply unit 141 to the liquid area 102a to be processed may be used, or a pressure gauge that measures the pressure every predetermined time may be used. . The measurement result of the pressure of the liquid to be processed supplied from the supply unit 141 to the liquid region to be processed 102 a measured by the pressure gauge is sent to the control unit 120.

The pressure of the liquid to be processed is measured with a pressure gauge in a state where the flow rate of the processing liquid discharged from the first discharge portion 142 of the processing tank 102 passing through the processing liquid pipe 108e is constant. .
Specifically, the flow rate of the processing liquid passing through the processing liquid pipe 108e may be made constant by adjusting the output of the pump 106 that pumps the processing target liquid to the supply unit 141. A flow rate adjusting valve may be provided in the pipe 108e, and the flow rate of the processing liquid passing through the processing liquid pipe 108e may be made constant by opening and closing the flow rate adjusting valve.
In this embodiment, since the flow rate of the processing liquid passing through the processing liquid pipe 108e is constant, the flow rate of the processing liquid discharged from the outflow pipe 108f as SS particles accumulate on the filter. Increases, and the pressure of the liquid to be processed supplied from the supply unit 141 to the liquid region 102a to be processed increases.

  When the control unit 120 determines whether or not the filter 10 needs to be cleaned based on the output from the pressure gauge (detecting means), and determines that the cleaning is necessary, the control unit 120 executes the cleaning, and determines that the cleaning is unnecessary Causes the process to be executed. In the present embodiment, the control unit 120 determines whether or not the filter 10 needs to be cleaned according to whether or not the measurement result of the pressure of the liquid to be processed sent from the pressure gauge is equal to or less than a predetermined threshold value. Thus, the bubble generating device 109 and the valve 107 are controlled. Whether the filter 10 needs to be cleaned by the control unit 120 may be determined every time the measurement result of the pressure of the liquid to be processed is sent from the pressure gauge, or may be determined at regular intervals.

  According to at least one embodiment described above, a supply unit to which a liquid to be processed is supplied, a filter that filters solids in the liquid to be processed, a first discharge unit that discharges the processing liquid that has passed through the filter, And a treatment tank having a second discharge part for discharging a part of the liquid to be processed supplied to the supply part, a bubble generating device capable of supplying bubbles to the liquid to be processed supplied to the supply part, Based on the detection means for detecting the filtration performance of the filter and the output from the detection means, it is determined whether or not the filter needs to be cleaned. The liquid to be treated is supplied to the supply unit, a part of the liquid to be treated is filtered through the filter, and the remaining part of the liquid to be treated is solidified on the filter together with the second discharge unit. From And when it is determined that the cleaning is unnecessary, the liquid to be processed without adding the bubbles is supplied to the supply unit, a part of the liquid to be processed is filtered by the filter, A control unit that executes a process of discharging the remaining part from the second discharge part, and the filter is formed on a plurality of through holes and at least a surface on a primary surface side into which the liquid to be processed flows, and the through hole By using a treatment system having a plurality of fine structures having a maximum outer dimension smaller than the average pore diameter, filtration of the liquid to be treated can be continued even during the washing step, and a high washing effect can be obtained.

Hereinafter, it demonstrates in detail using an Example.
Example 1
A stainless steel wire mesh (mesh size 34 μm, wire diameter 30 μm) was prepared. This was immersed in a plating bath containing phosphorus, zinc, and nickel, and nickel plating was performed. Thus, a wire mesh formed of a stainless steel wire (wire material) was covered with a base layer made of a nickel zinc alloy.

Thereafter, nickel plating treatment was performed by adding boric acid and ethylenediamine (EDA) as an additive to the plating bath in which the base layer was formed. By this, the plating layer which coat | covers the whole surface of the wire covered with the base layer was formed, and the filter of Example 1 was obtained.
The surface of the filter of Example 1 was observed with a scanning electron microscope (SEM), and it was confirmed whether or not a fine structure was formed on the surface. As a result, a plurality of needle-like structures were formed on the surface.

Next, the average pore diameter of the through holes was examined for the filter of Example 1. For the filter of Example 1, the number of needle-like structures per unit area (1 μm ² ), the number of needle-like structures per unit length (1 μm) in the cross section, the average height of the needle-like structures, the needle-like structures The coefficient of variation in height and the aspect ratio H (μm) / D (μm) between the average width D and the average height H of the base end portion of the acicular structure in the cross section were examined by the methods described above. Further, in order to calculate the number of needle-like structures per unit area (1 μm ² ), the number of needle-like structures per 4 μm ^{2 and the} number of needle-like structures per unit length (1 μm) in the cross section are calculated per 10 μm. The number of needle-like structures was also examined.

As a result, the average hole diameter of the through holes was 4 μm. The number of needle-like structures per 4 μm ² was 16 to 19 (the number of needle-like structures per unit area (1 μm ² ) (formation density) was 3.75) (see FIG. 4). Further, when this plating layer was fixed with embedded resin and then cut and observed for cross-section, the number of needle-like structures per 10 μm was 20 (the number of needle-like structures per unit length (1 μm) in the cross-section was 2). ). The average height H of the needle-like structures was 750 nm, and the coefficient of variation in the height of the needle-like structures was 0.28. Moreover, the average width D of the base end part of the acicular structure in a cross section was 550 nm, and the aspect ratio was 1.36.
Moreover, the width | variety between wire rods was 4 micrometers and the wire rod width | variety was 60 micrometers.

"Filtration test"
Next, the filter of Example 1 was installed in a treatment tank simulating the treatment system shown in FIG. 1, and a filtration test was performed under the following conditions.
In tap water, alumina particles having an average particle size of 3.0 μm as SS particles were dispersed at a concentration of 1000 mg / L to prepare a liquid to be treated, and pumped to a treatment tank via a pipe. And the filtration test which makes filtration pressure constant by 0.1 Mpa was performed by adjusting the output of a pump, and the process liquid turbidity was measured by the method shown below.
As a result, the turbidity was 0.5 NTU. Moreover, the processing liquid obtained by performing the filtration test was transparent.

“Turbidity of liquid in filtration test”
The turbidity of the treatment liquid that passed through the filter was measured 30 seconds after the start of the supply of the liquid to be treated to the treatment tank, and was defined as the treatment liquid turbidity.

  In addition, the filter after the filtration test is embedded in an embedding resin, and the cross section is observed with a scanning electron microscope (SEM). Three places were measured and the average value was calculated. FIG. 20 is a SEM photograph of the filter of Example 1 after the filtration test, showing the result of measuring the distance from the cake to the valley bottom of the fine structure. In the filter of Example 1 after the filtration test shown in FIG. 20, the average value of the distance between the cake and the valley bottom of the fine structure was 0.7 μm.

"Cleaning test"
After starting the supply of the liquid to be processed to the processing tank for 10 minutes, the processing step was performed in the same manner as the filtration test described above, and then bubbles were generated in the liquid to be processed using a bubble generator as shown below. The bubble-containing liquid to be processed was generated by feeding and pumped to the treatment tank. Then, by adjusting the output of the pump, a cleaning test was performed for 1 minute at a constant filtration pressure of 0.1 MPa, and the treatment liquid turbidity in the cleaning test was measured by the following method.
As a result, the turbidity was 0.7 FTU. Moreover, the processing liquid obtained by performing the washing test was transparent.

  The bubble-containing liquid to be treated is supplied with bubbles by introducing high-pressure air into the liquid to be treated that moves in the pipe from the air introduction part of the bubble generating device installed in the pipe that supplies the liquid to be treated to the treatment tank, The liquid to be treated and the bubbles were passed through an orifice which is a mixing part of the bubble generator.

  The conditions for introducing the high-pressure air introduced into the liquid to be treated are such that the diameter of bubbles obtained when air at 25 ° C. and 1 atm is introduced into tap water is 10 to 40 μm at 25 ° C. and 1 atm, and 20 μm is distributed. The pre-determined introduction condition that is the mode value of. Regarding the diameter of the bubbles, tap water supplied to the treatment liquid region of the treatment tank was immediately analyzed by a laser diffraction method.

Further, the surface of the filter after the cleaning test was observed. The results are shown in FIG. 21 and FIG.
FIG. 21 is a photograph of the filter of Example 1 before washing. FIG. 22 is a photograph of the filter of Example 1 after washing. As shown in FIGS. 21 and 22, the cake on the surface of the filter was peeled off by performing the cleaning test.

"Turbidity of processing solution in cleaning test"
The turbidity of the liquid to be treated that passed through the filter was measured 1 minute after the start of the washing test (the supply of bubbles to the liquid to be treated was started), and the turbidity was obtained.

  After such a cleaning test, the bubble generating device is stopped, the processing step is performed for 10 minutes in the same manner as the filtration test described above, and the turbidity of the processing liquid in the filtration test after the cleaning is measured by the following method. did. As a result, the turbidity was 0.9 NTU.

"Turbidity of processing solution in filtration test after cleaning"
The turbidity of the liquid to be treated that passed through the filter was measured 30 seconds after the washing test was stopped (the supply of bubbles to the liquid to be treated was stopped), and the turbidity was obtained.

  Further, the filtration rate in the filtration test before washing and the filtration test after washing is obtained, and the filtration rate in the filtration test after washing (10 minutes) with respect to the “filtration rate in the filtration test before washing (10 minutes)”. The recovery rate {= (after washing / before washing) × 100 (%)} was calculated. As a result, the recovery rate was 75%.

(Comparative Example 1)
In the cleaning test, in the same manner as in Example 1 before and after cleaning, except that the bubble generation device was stopped and tap water without adding bubbles was pumped to the treatment tank instead of the bubble-containing liquid to be treated. The filtration rate in the filtration test was measured, and the recovery rate was examined in the same manner as in Example 1. As a result, the recovery rate of Comparative Example 1 was 65%.
From this, it is possible to continue the filtration of the liquid to be processed even during the cleaning process by supplying the bubble-containing liquid to the primary side of the filter and filtering while washing the filter. It turns out that an effect is acquired.

(Example 2)
A cylindrical wire having a width of 900 μm made of stainless steel and wound around a support member and joined by sintering. The width between the wires is 30 μm, and the support member extends substantially parallel to the central axis. A material was prepared. This substrate was plated with nickel and covered with an underlayer made of nickel.
Thereafter, 2-butyne-1,4-diol was added as an additive to the plating bath on which the underlayer was formed, and nickel plating was performed. By this, the plating layer which coat | covers the whole surface of the base material coat | covered with the base layer was formed, and the filter of Example 2 was obtained.

  The surface of the filter of Example 2 was observed with a scanning electron microscope (SEM), and it was confirmed whether or not a fine structure was formed on the surface. As a result, a plurality of polyhedral structures were formed on the surface.

Next, for the filter of Example 2, the average pore diameter and the average maximum outer dimension of the through holes were examined by the methods described above.
As a result, the width between wires (average hole diameter of through-holes) was 6 μm, and the average maximum outer dimension was 4 μm. The wire width was 924 μm.

"Filtration test"
Next, the filter of Example 2 was installed in a treatment tank simulating the treatment system shown in FIG. 7, and a filtration test was performed under the following conditions.
In tap water, alumina particles having an average particle size of 0.1 μm as SS particles were dispersed at a concentration of 100 mg / L, and pumped to a treatment tank through a pipe for supplying a liquid to be treated. Then, by adjusting the output of the pump, a filtration test was conducted in which the filtration pressure was kept constant at 0.1 MPa, and the treatment liquid turbidity was measured in the same manner as in Example 1.
As a result, the turbidity was 0.6 FTU. Moreover, the processing liquid obtained by performing the filtration test was transparent.

  Further, the cross section of the filter after the filtration test was observed in the same manner as in Example 1, and the average value of the heights of the gaps was calculated in the same manner as in Example 1. As a result, the average value of the height of the gap was 0.7 μm.

"Cleaning test"
After starting the supply of the liquid to be processed to the processing tank for 10 minutes, the processing step was performed in the same manner as the filtration test described above, and then bubbles were generated in the liquid to be processed using a bubble generator as shown below. The bubble-containing liquid to be treated was generated by feeding and pumped to the treatment tank through the cleaning nozzle. Then, by adjusting the output of the pump, a washing test was conducted for 1 minute at a constant filtration pressure of 0.1 MPa, and the treatment liquid turbidity in the washing test was measured in the same manner as in Example 1.
As a result, the turbidity was 0.7 NTU. Moreover, the processing liquid obtained by performing the washing test was transparent.

The bubble-containing liquid to be treated was produced in the same manner as in Example 1.
The conditions for introducing the high-pressure air introduced into the liquid to be treated are such that the diameter of bubbles obtained when air at 25 ° C. and 1 atm is introduced into tap water is 0.5 to 10 μm at 25 ° C. and 1 atm, and 4 μm. Is a pre-determined introduction condition in which becomes the mode of the distribution. Regarding the diameter of the bubbles, tap water supplied to the treatment liquid region of the treatment tank was immediately analyzed by a laser diffraction method.

As the cleaning nozzle, one having a cylindrical main body sealed at one end and a plurality of jet nozzles having a circular shape in a plan view and discharging the bubble-containing liquid to be treated from the main body toward the outer peripheral direction and having an inner diameter of 2 mm was used.
Further, the surface of the filter after the cleaning test was observed with a scanning electron microscope (SEM). As a result, as in Example 1, the cake on the surface of the filter was peeled off.

After such a cleaning test, the bubble generating device is stopped, and the treatment process is performed for 10 minutes in the same manner as the filtration test described above. The treatment turbidity in the filtration test after the washing is performed in the same manner as in Example 1. Was measured. As a result, the turbidity was 0.9 NTU.
Moreover, the filtration rate in the filtration test (10 minutes) before washing | cleaning and the filtration test (10 minutes) after washing | cleaning was calculated | required, and the recovery rate was computed like Example 1. FIG. As a result, the recovery rate was 75%.

Example 3
The bubble generating device 109 is connected to the processing pipe 108h via the pipe 108c, and in the cleaning test, the liquid to be processed (bubble containing liquid to be processed) added with the bubbles supplied from the bubble generating device 109 is supplied to the first supply unit 141a. Except that it was supplied, the filtration rate in the filtration test before and after washing was measured in the same manner as in Example 2, and the recovery rate was examined in the same manner as in Example 1. As a result, the recovery rate of Example 3 was 70%.

(Comparative Example 2)
In the cleaning test, in the same manner as in Example 2 before and after cleaning, except that the bubble generating apparatus was stopped and the liquid to be treated that did not add bubbles was pumped to the treatment tank instead of the bubble-containing liquid to be treated. The filtration rate in the filtration test was measured, and the recovery rate was examined in the same manner as in Example 1. As a result, the recovery rate of Comparative Example 2 was 60%.

From the results of Example 2 and Comparative Example 2, it is possible to continue filtration of the liquid to be treated even during the washing process by supplying the liquid to be treated containing bubbles to the primary surface of the filter and filtering while washing the filter. It was found that an excellent cleaning effect was obtained with a high recovery rate.
Further, from the results of Example 2 and Example 3, it was found that a higher cleaning effect can be obtained by ejecting the liquid to be treated to which bubbles are added toward the primary surface of the filter by the cleaning nozzle.

(Comparative Example 3)
A filtration test before and after washing was performed in the same manner as in Example 2 except that a stainless wire mesh (wire diameter: 40 μm, mesh opening: 10 μm, twill) was used as a filter. The filtration rate was measured, and the recovery rate was examined in the same manner as in Example 1. As a result, the recovery rate of Comparative Example 3 was 60%.
From the results of Example 2 and Comparative Example 3, it was found that the cleaning effect was improved by using a filter having a plurality of polyhedral structures formed on the surface.

Example 4
The wire rods having the same width of 900 μm as in Example 2 and made of stainless steel in a cross-sectional view are arranged in parallel and joined by sintering on a support member extending in a direction substantially perpendicular to the wire rod, and the width between the wire rods is 30 μm. A plate-like substrate was produced. The plate-like substrate thus obtained was processed into a cylindrical shape, and in the same manner as in Example 1, a plating layer covering the entire surface of the substrate covered with the underlayer was formed. A filter was obtained.

  The surface of the filter of Example 4 was observed with a scanning electron microscope (SEM), and it was confirmed whether or not a fine structure was formed on the surface. As a result, a plurality of needle-like structures were formed on the surface.

Next, for the filter of Example 4, in the same manner as in Example 1, the average pore diameter of the through holes, the number of needle-like structures per unit area (1 μm ² ), and the needle-like structure per unit length (1 μm) in the cross section Number of objects, average height of needle-like structure, coefficient of variation of height of needle-like structure, aspect ratio H (μm) / average width D and average height H of the base end of needle-like structure in cross section / D (μm) was examined. Further, in order to calculate the number of needle-like structures per unit area (1 μm ² ), the number of needle-like structures per 4 μm ^{2 and the} number of needle-like structures per unit length (1 μm) in the cross section are calculated per 10 μm. The number of needle-like structures was also examined.

As a result, the average hole diameter of the through holes was 10 μm. The number of needle-like structures per 4 μm ² was 15, and the number of needle-like structures per unit area (1 μm ² ) was 3.75. The number of needle-like structures per 10 μm was 20, and the number of needle-like structures per unit length (1 μm) in the cross section was two. The average height H of the needle-like structures was 750 nm, and the coefficient of variation in the height of the needle-like structures was 0.28. Moreover, the average width D of the base end part of the acicular structure in a cross section was 550 nm, and the aspect ratio was 1.36.
The width between the wires was 6 μm, and the wire width was 924 μm.

"Filtration test"
Next, the filter of Example 4 was installed in a treatment tank simulating the treatment system shown in FIG. 8, and the filtration test was conducted in the same manner as in Example 2. The treatment turbidity was measured in the same manner as in Example 1. did.
As a result, the turbidity was 0.6 FTU. Moreover, the processing liquid obtained by performing the filtration test was transparent.

  Further, the cross section of the filter after the filtration test was observed in the same manner as in Example 1, and the average value of the heights of the gaps was calculated in the same manner as in Example 1. As a result, the average value of the height of the gap was 0.7 μm.

"Cleaning test"
After starting the supply of the liquid to be processed to the processing tank for 10 minutes, the processing step was performed in the same manner as the filtration test described above, and then bubbles were generated in the liquid to be processed using a bubble generator as shown below. The bubble-containing liquid to be treated was generated by feeding and pumped to the treatment tank through the cleaning nozzle. Then, by adjusting the output of the pump, a washing test was conducted for 1 minute at a constant filtration pressure of 0.1 MPa, and the treatment liquid turbidity in the washing test was measured in the same manner as in Example 1.
As a result, the turbidity was 0.7 NTU. Moreover, the processing liquid obtained by performing the washing test was transparent.

The bubble-containing liquid to be treated was produced in the same manner as in Example 1. The conditions for introducing the high-pressure air introduced into the liquid to be treated were the same as in Example 1.
The washing nozzle was arranged so that the direction of the bubble-containing liquid to be ejected was substantially tangential to the inner periphery of the filter. Further, as the cleaning nozzle, a nozzle having an inner diameter of 5 mm and in which a swirl flow along the inner peripheral surface of the filter is formed by the bubble-containing liquid to be processed ejected from the cleaning nozzle during the cleaning test is used. It was.

  Further, the surface of the filter after the cleaning test was observed with a scanning electron microscope (SEM). As a result, as in Example 1, the cake on the surface of the filter was peeled off.

After such a cleaning test, the bubble generating device is stopped, and the treatment process is performed for 10 minutes in the same manner as the filtration test described above. The treatment turbidity in the filtration test after the washing is performed in the same manner as in Example 1. Was measured. As a result, the turbidity was 0.9 NTU.
Moreover, the filtration rate in the filtration test (10 minutes) before washing | cleaning and the filtration test (10 minutes) after washing | cleaning was calculated | required, and the recovery rate was computed like Example 1. FIG. As a result, the recovery rate was 75%.

(Example 5)
The bubble generating device 109 is connected to the processing pipe 108h via the pipe 108c, and in the cleaning test, the liquid to be processed (bubble containing liquid to be processed) added with the bubbles supplied from the bubble generating device 109 is supplied to the first supply unit 141a. Except for supplying, the filtration rate in the filtration test before and after washing was measured in the same manner as in Example 4, and the recovery rate was examined in the same manner as in Example 1. As a result, the recovery rate of Example 5 was 70%.

From the results of Example 4, by supplying the bubble-containing liquid to be treated to the primary side of the filter and filtering while washing the filter, the liquid to be treated can be continuously filtered even during the washing process, and the recovery rate is high. It was found that an excellent cleaning effect can be obtained.
Moreover, from the results of Example 4 and Example 5, it was found that a higher cleaning effect can be obtained by ejecting the liquid to be treated to which bubbles are added toward the primary surface of the filter by the cleaning nozzle.

(Example 6)
The conditions for introducing the high-pressure air introduced into the liquid to be treated are as follows, and the same as in Example 2 except that the size of the bubbles in the liquid to be treated with bubbles added is 0.1 μm. Then, the filtration rate in the filtration test before and after washing was measured, and the recovery rate was examined in the same manner as in Example 1.
Using a nanobubble generator that generates bubbles of 1 μm or less as the bubble generator 109, the diameter of the bubbles obtained when air at 25 ° C. and 1 atmosphere is introduced into tap water is 100 to 200 nm at 25 ° C. and 1 atmosphere. Yes, the introduction condition was determined in advance so that 140 nm is the mode of the distribution. Regarding the diameter of the bubbles, tap water supplied to the treatment liquid region of the treatment tank was immediately analyzed by a laser diffraction method.
The recovery rate of Example 6 was 67%.

(Example 7)
The conditions for introducing the high-pressure air introduced into the liquid to be treated are as shown below, and the same as in Example 1 except that the size of the bubbles in the liquid to be treated with bubbles added is 50 mm. The filtration rate in the filtration test before and after washing was measured, and the recovery rate was examined in the same manner as in Example 1.
The bubble diameter obtained when air at 25 ° C. and 1 atm is introduced into tap water using a compressor as the bubble generating device 109 is 30 to 100 mm at 25 ° C. and 1 atm, and 50 mm is the mode of distribution. The pre-determined introduction conditions were as follows. Regarding the diameter of the bubbles, tap water supplied to the treatment liquid region of the treatment tank was immediately analyzed by a laser diffraction method.
The recovery rate of Example 7 was 68%.

  Examples 1 to 7 and Comparative Examples 1 to 3, the size of the bubbles in the liquid to be treated, the shape of the fine structure, the average pore diameter of the through holes, the formation density of the fine structure, and the unit of the fine structure Table 1 shows the number of formations per length, the average height of the fine structures, the coefficient of variation in the height of the fine structures, the average maximum outer dimensions, and the recovery rate.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

10, 90, 212, 291, 294, 297, 300, 370, 390 ... Filter, 3 ... Plating layer, 4 ... Underlayer, 5, 205, 305 ... Fine structure, 7 ... Cake, 13, 213 ... Through hole , 100, 100A ... treatment system, 101 ... treated liquid tank, 102, 102A ... treated tank, 102a ... treated liquid area, 102b ... treated liquid area, 103 ... treated liquid tank, 104 ... concentrated sludge tank, 106 ... pump 109 ... Bubble generating device.

Claims (14)

A supply unit to which the liquid to be processed is supplied, a filter for filtering solids in the liquid to be processed, a first discharge unit for discharging the processing liquid that has passed through the filter, and the liquid to be processed supplied to the supply unit A treatment tank having a second discharge part for discharging a part of
A bubble generating device capable of supplying bubbles to the liquid to be treated supplied to the supply unit;
Detection means for detecting the filtration performance of the filter;
Based on the output from the detection means, determine whether the filter needs to be cleaned,
When it is determined that the cleaning is necessary, the liquid to be processed to which bubbles are added by the bubble generating device is supplied to the supply unit, a part of the liquid to be processed is filtered by the filter, and the liquid to be processed The remaining part is discharged from the second discharge part together with the solid content deposited on the filter,
When it is determined that the cleaning is unnecessary, the liquid to be processed without adding the bubbles is supplied to the supply unit, a part of the liquid to be processed is filtered by the filter, and the remaining part of the liquid to be processed is A control unit that executes a process of discharging from the second discharge unit,
The filter has a plurality of through-holes and a plurality of microstructures formed on at least a surface on the primary surface side into which the liquid to be treated flows and having a maximum outer dimension smaller than an average hole diameter of the through-holes. .   The processing system according to claim 1, wherein the detection unit is a flow meter.   The processing system according to claim 1, further comprising a cleaning nozzle that ejects the liquid to be processed to which the bubbles are added toward the primary surface of the filter.   The processing system according to any one of claims 1 to 3, wherein the liquid to be processed to which the bubbles are added includes bubbles of 1 to 100 µm.   The processing system according to any one of claims 1 to 4, wherein an average hole diameter of the through holes is 0.1 µm to 5 mm.   6. The microstructure according to any one of claims 1 to 5, wherein the microstructure has at least one of a conical shape, an elliptical cone shape, a polygonal pyramid shape, a truncated cone shape, an elliptical truncated cone shape, and a polygonal truncated cone shape. The processing system described in. The processing system according to claim 6, wherein a formation density of the fine structures is in a range of 1.2 to 10.0 pieces / μm ² .   The processing system according to claim 6 or 7, wherein the number of the fine structures formed per unit length is in a range of 1.0 to 4.0 / μm.   The processing system according to any one of claims 6 to 8, wherein an average height of the fine structure is in a range of 0.2 to 2.5 µm.   The processing system according to claim 9, wherein a variation coefficient of the height of the fine structure is in a range of 0.15 to 0.50.   The processing system according to claim 1, wherein the fine structure has a polyhedral shape.   The processing system according to claim 11, wherein an average maximum outer dimension of the fine structure is in a range of 0.5 to 10 μm.   The processing system according to any one of claims 1 to 12, wherein the microstructure is formed of a metal or an alloy. A supply unit to which the liquid to be processed is supplied, a filter for filtering solids in the liquid to be processed, a first discharge unit for discharging the processing liquid that has passed through the filter, and the liquid to be processed supplied to the supply unit A treatment tank having a second discharge part for discharging a part of
A bubble generating device capable of supplying bubbles to the liquid to be treated supplied to the supply unit;
Detecting means for detecting the filtration performance of the filter,
The filter has a plurality of through-holes and a plurality of microstructures formed on at least a surface on the primary surface side into which the liquid to be treated flows and having a maximum outer dimension smaller than an average hole diameter of the through-holes. A processing method using
A step of determining whether the filter needs to be cleaned by the control unit based on an output from the detection means;
When it is determined that the cleaning is necessary, the liquid to be processed to which bubbles are added by the bubble generating device is supplied to the supply unit, and a part of the liquid to be processed is filtered by the filter, and the liquid to be processed A cleaning step of discharging the remaining portion of the second discharge portion together with the solid content deposited on the filter;
When it is determined that the cleaning is unnecessary, the liquid to be processed without adding the bubbles is supplied to the supply unit, a part of the liquid to be processed is filtered by the filter, and the remaining part of the liquid to be processed is A processing method including a processing step of discharging from the second discharge unit.