Water collection trough mechanism

Abstract

To provide a water collecting trough mechanism capable of efficiently dispersing an additive.SOLUTION: A water collection trough mechanism (50) includes a water collection trough (1), and a flow disturbing body (3) installed in a flow passage (1a) of the water collection trough (1) and having a wall surface (30) installed so as to partially obstruct a flow of water flowing in the flow passage (1a).SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a water collection trough mechanism. [Background technology]

[0002] It is known that water purification plants carry out a water purification process in which suspended solids contained in raw water taken from a river or other source are precipitated in a coagulation and sedimentation basin, and then the supernatant water is collected and filtered in a filtration basin, and coagulants and disinfectants are added during the process (Non-Patent Document 1).

[0003] Due to changes in natural conditions such as droughts caused by climate change, algae proliferation in closed water areas, and natural disasters such as typhoons and sudden heavy rains, as well as changes in social conditions such as increasing public demands for water quality, the addition of new water quality standards and stricter standard values, and a decrease in skilled technicians, water purification plants are increasing the number of locations where coagulants and other substances are injected to improve the performance of water purification treatment. For example, a mechanism known as two-stage coagulation, as described in Non-Patent Document 2, is known as a method for improving the effectiveness of water purification treatment. Two-stage coagulation is a mechanism in which coagulation treatment (addition of coagulant) is performed twice.

[0004] When adding additives for water purification such as the two-stage coagulation mentioned above twice, the location of addition varies depending on the water purification plant. For example, in Non-Patent Document 2, the second addition of coagulant is carried out in the sedimentation basin outflow conduit that collects the supernatant of the coagulation sedimentation basin. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] https: / / water-city-yamaguchi.com / for-kids / page_1078 / page_1085 / [Non-patent document 2] https: / / mhlw-grants.niph.go.jp / system / files / 2013 / 134061 / 201330004A / 201330004A0012.pdf Summary of the Invention [Problem to be solved by the invention]

[0006] It is known that the supernatant of a sedimentation basin is collected using a trough-like structure installed near the water surface of the basin, and this trough-like structure is called a water collection trough.

[0007] An object of one aspect of the present invention is to realize a water collection trough mechanism in which an additive added to water collected in the water collection trough is efficiently dispersed within the flow path of the water collection trough.An object of another aspect of the present invention is to provide a simulation method for simulating the dispersibility of an additive in a water collection trough mechanism in order to realize a water collection trough mechanism in which an additive added to water collected in the water collection trough is efficiently dispersed within the flow path of the water collection trough. [Means for solving the problem]

[0008] In order to solve the above problems, a water collection trough mechanism according to one embodiment of the present invention comprises a water collection trough and a blocking fluid installed within the flow path of the water collection trough and having a wall surface installed so as to partially block the flow of water flowing through the flow path. In order to solve the above problems, one embodiment of the present invention provides a simulation method executed by an apparatus for simulating the dispersion of an additive in a water collection trough mechanism that includes a water collection trough and a blocking fluid that is installed within the flow path of the water collection trough and has a wall surface that is installed so as to partially block the flow of water flowing through the flow path, and includes an acquisition step of acquiring (a) water collection trough information that indicates the shape of the water collection trough, (b) blocking fluid information that indicates the shape and position of the blocking fluid, (c) fluid information that indicates the state of the fluid flowing through the water collection trough, and (d) additive information that indicates the type of additive to be injected into the water collection trough and the method of injecting the additive into the water collection trough, and a generation step of generating data that indicates the dispersion status of the additive within at least a portion of a simulation target area that is an area downstream from the installation position of the blocking fluid in the water collection trough, based on the water collection trough information, the blocking fluid information, the fluid information, and the additive information acquired by the acquisition step. [Effects of the Invention]

[0009] According to one aspect of the present invention, it is possible to realize a water collection trough mechanism that efficiently disperses additives. Also, according to another aspect of the present invention, it is possible to provide a simulation method for simulating the dispersibility of additives in a water collection trough mechanism, in order to realize a water collection trough mechanism that efficiently disperses additives added to water collected in the water collection trough within the flow path of the water collection trough. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a partial external view of a water purification plant equipped with a water collection trough mechanism according to an embodiment of the present invention. FIG. [Figure 2] FIG. 2 is a perspective view of a water collecting trough provided in the water collecting trough mechanism according to one embodiment of the present invention. [Figure 3] FIG. 3 is a perspective view of another form of the water collecting trough shown in FIG. 2. [Figure 4] 1A and 1B are a top view and a side view of a water collecting trough mechanism according to one embodiment of the present invention; [Figure 5] 10A and 10B are a top view and a side view of a water collecting trough mechanism according to another embodiment of the present invention; [Figure 6] 10A and 10B are a top view and a side view of a water collecting trough mechanism according to another embodiment of the present invention; [Figure 7] FIG. 7 is another side view of the water collecting trough mechanism of FIG. 6. [Figure 8] FIG. 10 is a block diagram of a simulation device that executes a simulation method according to another embodiment of the present invention. [Figure 9] 10 is a flowchart of a simulation method according to another embodiment of the present invention. [Figure 10] FIG. 10 is an additive concentration contour diagram output by a generating unit as an example in a simulation process according to another embodiment of the present invention. [Figure 11] 3A and 3B are a top view and a side view of a water-blocking portion of a water-collecting trough disposed in the water-collecting trough mechanism of the first embodiment. [Figure 12] FIG. 10 is a diagram showing the analysis results of dispersibility in the water collecting trough mechanism of Example 1. [Figure 13] FIG. 10 is a diagram showing the results of an analysis of dispersibility in the water collecting trough mechanisms of Examples 2, 3 and 4. [Figure 14] 10A and 10B are a top view and a side view of a water blocking fluid disposed in a water collecting trough mechanism of Example 5. [Figure 15] FIG. 1 is a graph showing raw water turbidity, treated water turbidity, and turbidity removal rate in Experiment 1 of Example 5. [Figure 16] 10 is a graph showing the number of particles in raw water, the number of particles in treated water, and the particle removal rate in Experiment 1 of Example 5. FIG. [Figure 17] FIG. 10 is a graph showing the turbidity removal rate after long-term water flow in Experiment 2 of Example 5. [Figure 18] FIG. 10 is a graph showing the particle removal rate in long-term water flow in Experiment 2 of Example 5. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Embodiment 1] [Water collection trough mechanism] A water collection trough mechanism according to one embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a schematic external view of a portion of a water purification treatment facility 100. Fig. 2 is a perspective view of a water collection trough mechanism 50 provided in a portion of a coagulation sedimentation basin 120 of the water purification treatment facility 100. Based on the finding that adding an additive to the water collection trough mechanism 50 in the coagulation sedimentation basin 120 improves water purification efficiency, the present inventors have discovered a water collection trough mechanism 50 that improves the dispersibility of the additive.

[0012] The water collection trough mechanism 50 includes a water collection trough 1. As shown in FIG. 1, multiple water collection troughs 1 are arranged parallel to one another in the sedimentation basin 120. In the following explanation, unless otherwise specified, a single water collection trough 1 will be described. The water collection trough mechanism 50 described below is applicable to all water collection troughs arranged in the sedimentation basin 120, but may also be applied to only some of them.

[0013] The water collection trough 1 includes a flow path 1a (Fig. 2) that collects and discharges supernatant water from the water accumulated in the sedimentation basin 120. The water flowing through the flow path 1a flows out from the downstream end 1c (outlet) shown in Fig. 1 and flows into the rapid sand filter basin 140 via the outflow conduit 130. Note that Fig. 1 is an example, and the manner in which the water is introduced from the downstream end 1c to the outflow conduit 130 is not limited to this.

[0014] The water collection trough 1 is placed near the water surface of the water accumulated in the coagulation sedimentation basin 120. The water surface of the water accumulated in the coagulation sedimentation basin 120 is located above the bottom surface of the water collection trough 1. As will be described later, the side surface of the water collection trough 1 is configured to allow the supernatant water of the coagulation sedimentation basin 120 to flow into the flow path 1a over the entire length of the flow path 1a.

[0015] 2, the flow path 1a of the water collecting trough 1 will be described. The flow path 1a has a bottom surface 11 extending in the direction of water flow, and a pair of side surfaces 12a and 12b rising from the end of the bottom surface 11 and extending in the direction of water flow. In short, the flow path 1a refers to the portion formed by the inner surface of the water collecting trough 1.

[0016] In this specification, when describing each component of the water collecting trough mechanism 50, an XYZ three-dimensional coordinate system is used, with the extension direction of the flow path 1a of the water collecting trough 1 being the Y-axis direction, the width direction of the flow path 1a (the direction of the shortest separation between the pair of side surfaces 12a, 12b) being the X-axis direction, and the direction perpendicular to each of the X-axis and Y-axis being the Z-axis direction. Note that the positive Y-axis direction is the flow direction of water in the flow path 1a, and the Z-axis direction is the vertical direction. The XY plane is also considered to be a horizontal plane.

[0017] The bottom surface 11 extends along the Y axis, and side surfaces 12a, 12b stand upright from both ends of the bottom surface 11 along the Y axis. The bottom surface 11 is, for example, a horizontal surface. However, the bottom surface 11 is not limited to a horizontal surface. For example, in a cross-sectional view of the water collecting trough 1 on the XZ plane, the bottom surface 11 may have a U-shaped cross section in which the pair of side surfaces 12a, 12b are the highest and the intermediate position between the side surfaces 12a and 12b is the deepest.

[0018] A pair of side surfaces 12a, 12b are provided with a plurality of orifices 14 (inflow sections). The plurality of orifices 14 are provided in a row along the Y direction at the top of flow path 1a, i.e., at the top of each of side surfaces 12a, 12b. The orifices 14 are designed to be located a predetermined depth below the surface of the water accumulated in sedimentation basin 120. This allows the supernatant water near the surface of the water accumulated in sedimentation basin 120 to flow into flow path 1a through the orifices 14.

[0019] The predetermined water depth includes a certain range of values ​​because, while the water collection trough 1 is fixed in a predetermined position and its vertical position does not change, the water level accumulated in the sedimentation basin 120 fluctuates depending on the time of day, weather conditions, etc. In other words, the positional relationship between the water surface accumulated in the sedimentation basin 120 and the orifice 14 is not constant.

[0020] The number, formation positions, and hole diameters of the orifices 14 can be designed as appropriate depending on the size of the flow path 1a of the water collection trough 1, the design value of the amount of water to be passed through the flow path 1a, etc. In the example of Fig. 2, each of the pair of side surfaces 12a, 12b has one row of orifices 14.

[0021] The mechanism for causing the supernatant water of the flocculation sedimentation basin 120 to flow into the flow path 1a of the water collecting trough 1 is not limited to the orifice 14. FIG.

[0022] The water collecting trough 1A shown in upper side A of Fig. 3 has a plurality of cutouts 16 (inflow portions) arranged along the water flow direction at the upper ends of a pair of side surfaces 12a, 12b. The cutouts 16 are V-shaped notches that gradually taper toward the bottom surface 11, and allow supernatant water from the coagulation and sedimentation basin 120 outside the water collecting trough 1A to flow into the flow path 1a of the water collecting trough 1A through the cutouts 16. Note that the shape, number, and size of the cutouts are not limited to those shown in the figure.

[0023] The water collecting trough 1B shown on the lower side B of Figure 3 does not have an orifice 14 or a notch 16, and water can flow into the flow path 1a of the water collecting trough 1B from the upper ends 12c and 12d (inlet portions) of the sides 12a and 12b, respectively.

[0024] The water collecting trough mechanism 50 further includes a blocking fluid 3 in the flow path 1a of the above-described water collecting trough 1. In Fig. 4, the upper side of the page shows a top view of the water collecting trough 1, and the lower side of the page shows a view of the water collecting trough 1 from the downstream end 1c toward the upstream side.

[0025] The blocking fluid 3 is installed downstream of the additive addition point within the flow path 1a of the water collecting trough 1. The blocking fluid 3 has a wall surface 30 that is installed so as to block a portion of the flow of water flowing through the flow path 1a. By placing the wall surface 30 so as to block a portion of the flow of water flowing through the flow path 1a, the flow of water is blocked, causing turbulence downstream of the wall surface 30, which allows the additive to be dispersed efficiently.

[0026] The wall surface 30 is a vertical surface, and this vertical wall surface 30 is inclined with respect to the extension direction of the flow path 1a (i.e., the Y-axis direction). In the upper view of Fig. 4, the wall surface 30 is configured as a vertical surface that extends in a direction intersecting the Y-axis, blocking the flow of water flowing in the positive direction of the Y-axis.

[0027] The blocking fluid 3 further has a bottom 31 fixed to the bottom surface 11 of the water collecting trough 1, and a wall surface 30 stands upright from the bottom 31. The width (length in the X-axis direction) of the wall surface 30 when viewed from the direction shown at the bottom of the paper in Fig. 4 is slightly shorter than the width of the water collecting trough 1 (shortest distance between side surface 12a and side surface 12b), and is able to block the flow of water flowing near the bottom surface 11. The blocking flow disrupts the water flow, which in turn disperses the additive added upstream into the water.

[0028] There are no particular limitations on the method for fixing the water blocking device 3 (bottom 31) to the water collecting trough 1, and as in this embodiment, it can be appropriately selected depending on the material of the bottom surface 11 of the water collecting trough 1, etc. Examples include welding, screw fastening, and fitting.

[0029] The location where the fluid blocking member 3 is fixed to the water collecting trough 1 is not limited to the bottom surface 11. The fluid blocking member 3 may be fixed to the side surfaces 12a and 12b of the water collecting trough 1 as long as the wall surface 30 can be arranged to be inclined with respect to the extension direction of the flow path 1a (i.e., the Y-axis direction).

[0030] Here, the lower side of FIG. 4 shows, as an example, the relationship between the height of the wall surface 30 from the bottom surface 11 along the positive direction of the Z axis, the position of the orifice 14, and the water surface position of the flowing water. In this example, the height of the wall surface 30 (the length from the bottom surface 11 along the positive direction of the Z axis) is lower than the water surface position of the water flowing through the flow path 1a and is equal to or less than half the water depth. If the height of the wall surface 30 is higher than the water surface position, the water flowing through the water collection trough 1 may overflow from the water collection trough 1. On the other hand, if the height of the wall surface 30 is less than one-fifth the water depth, the blocking effect is low. Note that the water surface position (water depth) of the water flowing through the flow path 1a of the water collection trough 1 varies depending on the size of the flow path 1a of the water collection trough 1 and also fluctuates with the fluctuation of the water surface position of the coagulation sedimentation basin 120 described above. Therefore, the relationship between the height of the wall surface 30 and the water surface position of the water flowing through the water collection trough 1 is not limited to the above.

[0031] The inclination angle of the wall surface 30 with respect to the Y-axis direction (first axis direction) is not particularly limited, and it is sufficient that the wall surface 30 is not parallel to the Y-axis when viewed from above as shown in the upper part of the paper of FIG.

[0032] The walls 30 and bottom 31 may be constructed from chemically, weather- and water-resistant materials used in known water collection troughs.

[0033] The wall surface 30 is realized by the surface of a single plate-like structure disposed on the upper surface of the bottom portion 31. There is no particular limitation on the thickness of this plate-like structure. Because the wall surface 30 is a single plate-like structure, the inclination angle θ is constant from the end close to one side surface 12a to the end close to the other side surface 12b.

[0034] The wall surface 30 is formed by the surface on one side of a single plate-like structure, and the entire surface is a vertical plane. However, this is not limited to this, and a part of the surface may be a surface that is not a vertical plane. Furthermore, a part of the surface may be a surface that is not inclined at the above-mentioned inclination angle, for example, a part of the surface may be a surface that is not inclined at the above-mentioned inclination angle and is along the Y-axis direction.

[0035] As described above, by fixing the blocking fluid 3 to the water collecting trough 1, it is possible to improve the dispersibility of the additives added to the water collecting trough 1. This also applies when additionally introducing a blocking fluid 3 into an existing water collecting trough that does not have a blocking fluid 3.

[0036] <Additives> Here, we will explain the additive. The point at which the additive is added to the flow path 1a can be set at any location in the extension direction (length direction) of the flow path 1a of the water collection trough 1. When the addition point is set at a position close to the upstream end 1b (Fig. 2), the length of the flow path 1a downstream from the addition point is relatively long, so it is thought that the additive will be dispersed to a certain extent as it flows, but by providing the blocking fluid 3, the dispersion is further improved.

[0037] However, the present invention is not limited to providing the addition point near the upstream end 1b (FIG. 4). In this embodiment, even if the length of the flow path 1a downstream of the addition point is short, the additive can be effectively dispersed by the blocking fluid 3. Therefore, for example, the addition point can be provided near the downstream end 1c.

[0038] In FIG. 4, the addition point 5a is located on the center line of the flow channel 1a (the imaginary line y of the Y-axis), but this is not limitative and the addition point 5a may be located at a position offset from the center line.

[0039] Examples of additives include a flocculant, a chlorine agent, an acid agent, an alkali agent, and the like, and one specific example of each is shown, but the additives are not limited to these. · Flocculants; Polyaluminum Chloride (PAC) Aluminum oxide concentration: 10.0 to 11.0 wt% Specific gravity (20℃): 1.19 or more ·Chlorine agents; Sodium hypochlorite Available chlorine concentration: 12.0% Specific gravity (20℃): 1.2 Acidifiers; sulfuric acid Concentration: 75% Specific gravity (20℃): 1.67 ·Alkaline agent; Sodium hydroxide Concentration: 48% Specific gravity (20℃): 1.51 It is also possible to add a plurality of types from these examples through the addition section 5.

[0040] As an example of a method for adding the additive, a mechanism can be adopted in which the water collection trough mechanism 50 further includes an addition section 5 for adding the above-mentioned additive to the flow path 1a, and a predetermined amount of additive is added to the water flowing through the flow path 1a.

[0041] When the addition unit 5 is provided, the addition unit 5 may include at least a pipe, the tip of which is located above the flow path 1a, and may be configured as a mechanism for adding the additive from the tip toward the water flowing through the flow path 1a. A pump for pumping the additive may be further included for addition. The addition unit 5 may be installed at a location in the flow path 1a where the additive is desired to be added or near a location where the additive can be added, and the pipe may be extended. The addition unit 5 may be installed, for example, on top of a block wall 122 with a flow straightening hole 123 located in the coagulation sedimentation basin 120 in Figure 1.

[0042] However, the present invention is not limited to an embodiment that includes the addition unit 5. An embodiment may also be one in which the addition unit 5 is not provided and a predetermined additive is manually added to the water flowing through the flow path 1a by an operator.

[0043] [Embodiment 2] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0044] The water collecting trough mechanism 50A of this embodiment is the same as that of the first embodiment, except that the shape of the wall surface of the water blocking device 3 is different from that of the wall surface 30 of the first embodiment shown in FIG.

[0045] 5 shows, at the top, a diagram of the water collecting trough 1 of the water collecting trough mechanism 50A of this embodiment, and, at the bottom, a diagram of the water collecting trough 1 as viewed upstream from the downstream end 1c. Fig. 5 is a drawing corresponding to Fig. 4 of the first embodiment.

[0046] A comb-shaped blocking member 3A is disposed in the flow path 1a of the water collecting trough 1 of the water collecting trough mechanism 50A. The comb-shaped blocking member 3A has a plurality of protrusions 32 protruding from the bottom surface 11 of the water collecting trough 1 in a comb shape, and each of the protrusions 32 is provided with a wall surface 30A. Each of these wall surfaces 30A is inclined with respect to the extension direction of the flow path 1a, i.e., the Y-axis direction. The inclination angle θ of the wall surface 30A with respect to the Y-axis direction (shown on the right side of the paper in FIG. 5) may be the same as the inclination angle θ of the wall surface 30 in the first embodiment, or may be different. The height of the wall surface 30A may also be the same as the height of the wall surface 30 in the first embodiment, or may be different.

[0047] In this embodiment, as shown in the upper part of FIG. 5 , a row of five convex portions 32 is arranged along the width (X-axis direction) of the water collecting trough 1, and a row of four convex portions 32 are arranged alternately along the water flow direction (Y-axis direction), for a total of four rows. Here, as shown on the right side of FIG. 5 , these rows are arranged such that the convex portion 32 in the downstream row is located between the convex portions 32 in the upstream row of two rows arranged along the water flow direction (indicated as W in the partial enlarged view shown on the right side of FIG. 5 ). With this arrangement, water passing between the convex portions 32 in the upstream row is also blocked by the wall surfaces 30A of the convex portions 32 in the downstream row, thereby improving the dispersibility of the additive. Note that the example of FIG. 5 shows an embodiment in which a total of four rows are arranged alternately along the water flow direction (Y-axis direction), but the number of rows is not limited to four. Furthermore, the number of convex portions 32 arranged in each row is not limited to the example of FIG. 5 . 5, the bottom 31 is independent for each row, but this is not a limitation. As with the first embodiment, there is no particular limitation on the method for fixing the comb-shaped water blocking member 3A to the water collecting trough 1.

[0048] In this way, the water collecting trough mechanism 50A of this embodiment can also efficiently disperse the additives added in the water collecting trough 1, similar to the water collecting trough mechanism 50 of the first embodiment.

[0049] [Embodiment 3] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0050] The water collecting trough mechanism 50B of this embodiment differs from the first embodiment in that it includes another blocking fluid in addition to the blocking fluid 3 of the water collecting trough mechanism 50 of the first embodiment.

[0051] In Fig. 6, the upper side of the page shows a top view of the water collecting trough 1 of the water collecting trough mechanism 50B of this embodiment, and the lower side of the page shows a view of the water collecting trough 1 viewed upstream from the downstream end 1c. Fig. 6 corresponds to Fig. 4 of the first embodiment. Fig. 7 shows a view of the water collecting trough 1 viewed downstream from the upstream end 1b.

[0052] The water collecting trough 1 of the water collecting trough mechanism 50B has, in its flow path 1a, a blocking fluid 3 (first blocking fluid) that is the same as the blocking fluid 3 of embodiment 1, and an upstream blocking fluid 3D (second blocking fluid) that is installed at a position upstream of the position where the blocking fluid 3 is installed. A description of the blocking fluid 3 that is the same as the blocking fluid 3 of embodiment 1 will be omitted.

[0053] The upstream baffle 3D has a wall surface 30D similar to the wall surface 30 of the baffle 3. That is, the wall surface 30D has a vertical surface and is inclined with respect to the extension direction of the flow path 1a, i.e., the Y-axis direction. Furthermore, the wall surface 30D of the upstream baffle 3D has a bent portion 33 on the upstream side of the flow path 1a in a top view, and is V-shaped and open toward the downstream side.

[0054] The upstream baffle 3D is V-shaped in top view, forming two equal sides of an isosceles triangle. In one example, the upstream baffle 3D can be realized by bonding two plates together at a bend 33. The bend 33 is located on the central axis y of the flow channel 1a.

[0055] 7, the wall surfaces 30D located on both sides of the bent portion 33 face upstream, and the inclination angle θ of each wall surface 30D with respect to the Y-axis direction may be the same as or different from the inclination angle θ of the wall surface 30 of embodiment 1. The height of the wall surface 30D may also be the same as or different from the height of the wall surface 30 of embodiment 1.

[0056] Water flowing from upstream of the upstream blocking fluid 3D starts from the bend 33 located on the central axis y of the flow path 1a, is straightened toward each of the side surfaces 12a and 12b by the wall surfaces 30D located on both sides, and then creates a flow in a direction along each of the side surfaces 12a and 12b (positive direction of the Y axis).

[0057] By creating such a flow upstream of the additive addition point, the flow of water near the addition point is rectified, and the additive added on the central axis y can be rectified so that it flows along the Y-axis near the central axis y of the flow channel 1a.

[0058] The inventors have identified that the flow of water in a typical water collection trough is not constant. This is thought to be due to, for example, slight fluctuations in the amount of water flowing in from the orifice 14. Therefore, by installing an upstream baffle 3D upstream of the addition point, the flow of water near the addition point can be rectified, and the additive flowing with the water from the addition point is effectively blocked by the wall surface 30 of the downstream baffle 3, allowing it to be dispersed efficiently.

[0059] In this way, by providing blocking fluids both upstream and downstream of the addition point, the flow near the addition point can be blocked and regulated, and the blocking effect of the blocking fluid 3 located downstream can be further enhanced, making it possible to further improve dispersibility.

[0060] In this embodiment, the blocking fluid 3 downstream of the addition point has the same configuration as the blocking fluid 3 in the first embodiment, but is not limited to this and may have the same configuration as the blocking fluid 3A in the second embodiment.

[0061] Furthermore, one embodiment of the present invention also includes an embodiment in which a baffle fluid is not provided downstream of the additive addition location, but is provided only upstream of the additive addition location.

[0062] In addition, in this embodiment, blocking fluids are provided upstream and downstream of the addition point, but it is also possible to provide a blocking fluid 3 upstream of the addition point and an upstream blocking fluid 3D further upstream of that.It is also possible to provide an upstream blocking fluid 3D downstream of the addition point and an upstream blocking fluid 3 further downstream of that.

[0063] [Embodiment 4] In this embodiment, a simulation method executed by a device (hereinafter referred to as a "simulation device") that simulates the dispersibility of additives in the water collecting trough mechanisms 50, 50A, and 50B of the above-described embodiments will be described.

[0064] FIG. 8 is a block diagram showing the configuration of a simulation device that uses CFD analysis to simulate the dispersibility of additives in a water collection trough mechanism that includes a water collection trough and a blocking fluid that is installed in the flow path of the water collection trough and has a wall surface that is installed so as to partially block the flow of water through the flow path.

[0065] As shown in FIG. 8 , the simulation device 60 is an information terminal connected to a network such as the Internet. The simulation device 60 may be an information terminal such as a smartphone, tablet, or PC provided for simulating the dispersibility of an additive in a water collection trough, or a terminal dedicated to simulation, and may be connected to a network 610 such as the Internet. The simulation device 60 can transmit and receive various data to and from other information terminals 600 such as mobile phones, smartphones, tablets, and PCs (personal computers) via the network 610. For example, the results of a simulation performed by the simulation device 60 can be transmitted to an information terminal such as a user's smartphone via the network 610. The simulation device 60 can acquire information necessary for the simulation via the network 610, but may not be connected to the network 610. In the present embodiment, the following description will be given assuming that the simulation results are displayed on the simulation device 60.

[0066] As shown in FIG. 8, the simulation device 60 includes a storage unit 61, a control unit 62, an input / output unit 63, a communication unit 64, and a system bus (not shown) that interconnects these units.

[0067] The storage unit 61 includes a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The ROM stores a program 611 to be executed by a CPU (Central Processing Unit) of the control unit 62, and various data (not shown) required in advance for executing the program 611. The various data include various parameters, etc. The various parameters may be stored in the storage unit 61 based on input from the input / output unit 63, or may be stored in advance. The various data include data required for simulation in addition to the various parameters, etc.

[0068] The program 611 is a program for executing a simulation process, which will be described later. Specifically, the program 611 is a program for realizing the functions of a fluid analysis unit 623, an acquisition unit 624, and a generation unit 625, which will be described later, and is stored in advance in the storage unit 61.

[0069] The control unit 62 is configured with a CPU, an ASIC (Application Specific Integrated Circuit), etc. The control unit 62 operates in accordance with a program 611 stored in the storage unit 61, and executes processing in accordance with the program. The control unit 62 includes a fluid analysis unit 623, an acquisition unit 624, and a generation unit 625 as main functional units provided by the program 611 stored in the storage unit 61.

[0070] The fluid analysis unit 623 analyzes information on the fluid supplied to the water collection trough (hereinafter referred to as "supply information") and generates fluid information for the region to be analyzed, which is used by the generation unit 625. The analysis target refers to at least a part of the region in the water collection trough through which the fluid flows, and in this embodiment, the region analyzed by the fluid analysis unit 623 is from the upstream end to the downstream end of the water collection trough.

[0071] Fluid information is information that indicates the state of the fluid flowing through the water collection trough. Examples of the fluid state include the fluid flow rate, flow velocity (e.g., velocity distribution), pressure, turbulent energy, and turbulent energy dissipation rate. In addition, for example, information on the type, specific gravity, temperature, etc. of the fluid may also be used as information indicating the fluid state.

[0072] Here, in order to analyze the dispersion of the additive in a short time, it is considered sufficient to limit the analysis target to the region downstream (secondary side) from the position where the aforementioned blocking fluid is installed, but the analysis is significantly affected by the analysis results upstream (primary side) from the position where the aforementioned blocking fluid is installed. Therefore, the fluid analysis unit 623 sets not only the region downstream (secondary side) from the position where the blocking fluid is installed, but also the region upstream from the position where the blocking fluid is installed as the simulation target region. On the other hand, in order to prevent an increase in the analysis time required due to a wide simulation target region, the fluid analysis unit 623 analyzes only half the width of the water collection trough.

[0073] The supply information used by the fluid analysis unit 623 may be input by the user, or as described below, the fluid analysis unit 623 may perform a more detailed analysis using the inflow conditions of the fluid into the water collection trough (for example, information about the fluid dropping from an orifice, etc.) etc. Examples of information about the fluid to be supplied to the water collection trough include information indicating the position on the water collection trough from which the fluid will flow in (for example, information indicating the position of a fluid inlet provided on the side, etc.), the inflow amount of the fluid to be supplied from that position, etc.

[0074] In this embodiment, as an example of the region to be analyzed, the size of the region to be analyzed (the size of the water collection trough) is 6.4 m × 0.195 m × 0.20 m. 6.4 m corresponds to the total length of the water collection trough, and the flow path width of the water collection trough is 0.40 m, so the region to be analyzed is 0.20 m, which is half that width. The fluid analysis unit 623 performs the analysis using a steady, single-phase flow (liquid), turbulent flow model (k-ε model). Here, the fluid used in the analysis by the fluid analysis unit 623 may be only water (density, dynamic viscosity coefficient), but it is also possible to analyze additives as well.

[0075] As a result of the analysis, the fluid analysis unit 623 generates fluid information such as the pressure of the fluid in the simulation target region, the velocity components (x, y, z) of the fluid, the turbulent energy, and the turbulent energy dissipation rate.

[0076] As described above, the fluid analysis unit 623 may generate supply information by analyzing the inflow conditions of fluid into the water collection trough. For example, conditions indicating water falling behavior may be generated using information about the fluid falling from an orifice or the like, and this may be used as supply information to generate fluid information. Information indicating water falling behavior includes at least one of information indicating the water level in the water collection trough, the position of the water falling from the orifice, the water landing speed, the liquid volume fraction, the falling water speed components (x, y, z), etc. This information can be calculated from experiments, simulations, theoretical values, etc.

[0077] The acquisition unit 624 acquires the following information (a) to (d): (a) Water collection trough information; (b) fluid barrier information; (c) fluid information; and (d) Additive information Each piece of information will be explained below.

[0078] (a) Water collection trough information The water collection trough information includes information indicating the shape of the water collection trough, such as the length, width, and depth of the water collection trough.

[0079] (b) Fluid barrier information The fluid blocking information includes information indicating the shape and location of the fluid blocking member. The fluid blocking information may also include information regarding the material of the fluid blocking member, for example.

[0080] (c)Fluid information The fluid information is as explained above as information generated by the fluid analysis unit 623.

[0081] (d) Additive information The additive information includes information indicating the type of additive to be injected into the water collection trough and the method of injecting the additive into the water collection trough. Examples of the injection method include the injection position, injection amount, density of the additive, and diffusion coefficient. In this embodiment, a form using PAC as an example of an additive will be described.

[0082] The information (a), (b), and (d) may be information input by the input / output unit 63. The acquisition unit 624 acquires the information (c) from the fluid analysis unit 623. By referencing the analysis results generated by the fluid analysis unit 623, the generation unit 625 (described later) may use the analysis results of the fluid analysis unit 623 as fluid information for the most upstream region within the secondary region (the region downstream from the position where the baffle fluid is installed) that is the simulation target region. In other words, the above-mentioned fluid information (c) may be information obtained by further processing the analysis results generated by the fluid analysis unit 623. For example, as described herein, such information processing may involve processing information indicating a fluid flowing from the top to the bottom of the water collection trough into information that approximates the start of the fluid flow from a certain point (in this example, a predetermined point upstream from the position where the baffle fluid is installed). For example, as mentioned above, the fluid analysis unit 623 obtains information indicating the fluid over the entire 6.4 m, and as will be described later, the analysis area size (water collection trough) is set to 2.028 m, so processing can be performed to approximate the fluid starting at a position 2.028 m from the bottom.

[0083] In short, by using the aforementioned fluid analysis unit 623, steady-state calculations are possible, single-phase flow analysis is possible, and the analysis domain can be optimized (analysis of only the secondary side), making it possible to perform CFD analysis in a short time.

[0084] The fluid analysis unit 623 performs analysis using half the width of the flow path of the water collecting trough. Therefore, when acquiring fluid information that is the analysis result of the fluid analysis unit 623, the acquisition unit 624 may invert the analysis result of the half width at the middle position of the width of the water collecting trough to create data for the remaining half width, and connect this to the analyzed data for the half width to acquire the analysis result for the full width.

[0085] In addition, the present invention is not limited to the aspect in which fluid information is generated by the fluid analysis unit 623, and one aspect of the present invention is that, without performing analysis by the fluid analysis unit 623, the user inputs information corresponding to the fluid information into the input / output unit 63, and the acquisition unit 624 acquires this information.

[0086] The generating unit 625 generates data indicating the dispersion state of the additive in at least a part of the simulation target area in the water collecting trough based on the information (a) to (d) acquired by the acquiring unit 624.

[0087] The generation unit 625 analyzes the area downstream (secondary side) from the position where the blocking fluid is installed. As an example, the generation unit 625 sets the analysis area size (water collection trough) to 2.028 m × 0.14 m × 0.40 m. The injection point position is set to 2.020 m from the downstream end of the water collection trough, and the injection amount is set to 1.0 mg / L.

[0088] The generation unit 625 analyzes data showing the dispersion state of the additive using a steady-state calculation, single-phase flow (liquid), two-liquid mixture, and turbulent flow model (k-ε model). Here, the fluids used by the generation unit 625 for analysis are water (density, kinematic viscosity coefficient) and additive (PAC) (density, kinematic viscosity coefficient). The generation unit 625 may perform calculations iteratively to improve accuracy. The number of iterations may be, for example, 100 or more and 10,000 or less.

[0089] The generation unit 625 generates the additive concentration at the downstream end of the water collection trough, the additive dispersion state within the analysis region, the additive concentration within the analysis region, and the velocity components (x, y, z) of the additive-containing fluid within the analysis region as analysis results. The generation unit 625 may generate the additive dispersion state, additive concentration, and additive velocity components (x, y, z) within at least a portion of the analysis region as analysis results. However, the generation unit 625 may also generate the additive dispersion state, additive concentration, and additive velocity components (x, y, z) throughout the entire analysis region as analysis results. In this embodiment, the generation unit 625 generates a variance value indicating the additive dispersion state. The variance value indicates the deviation between the average additive concentration within the analysis region and the additive concentration in a certain portion of the analysis region. The variance value will be described later. In this embodiment, the generation unit 625 generates the variance value, but this is not limiting. The variance value may also be calculated outside the simulation device 60 (for example, by another device).

[0090] The operation of the simulation device 60 will be described with reference to Fig. 9. Fig. 9 is a flowchart showing an example of a simulation method.

[0091] 9 starts, the control unit 62 first analyzes information about the fluid to be supplied to the water collection trough using the function of the fluid analysis unit 623 to generate fluid information (step S101) (fluid analysis step), as described above in detail.

[0092] 9, the control unit 62 receives the input of the above-mentioned (a) water collection trough information, (b) fluid blocking information, and (d) additive information from the input / output unit 63 through the acquisition unit 624, and also receives the (c) fluid information from the fluid analysis unit 623 (step S102) (acquisition step). When analysis is performed without using the fluid analysis unit 623, the control unit 62 also receives the input of the (c) fluid information from the input / output unit 63 through the acquisition unit 624.

[0093] 9, the control unit 62 causes the generation unit 625 to generate the additive concentration at the downstream end of the water collecting trough, the dispersion state of the additive in the analysis region, the additive concentration, and the velocity components (x, y, z) of the additive (step S103) (generation step). The control unit 62 may cause the generation unit 625 to calculate a dispersion value as the dispersion state of the additive.

[0094] The dispersion value can be calculated using the following formula (1). The dispersion value is the "average of the squares of the deviations (the difference between each value and the average value)," and the closer it is to zero, the more uniformly the additives are dispersed.

number

[0095] Here, the mesh in equation (1) is the mesh located at the outlet of the analysis domain (downstream end of the water collection trough) among the meshes obtained by dividing the analysis domain size three-dimensionally into predetermined sizes.

[0096] 10 shows an example of an additive concentration contour map output by the generating unit 625. In FIG. 10, concentration contour maps are created at 0.5 m intervals within the analysis region of the water collection trough.

[0097] As described above, according to this embodiment, the dispersibility of an additive in a water collection trough mechanism can be evaluated. This allows the dispersibility to be evaluated more simply and quickly than when conducting experiments in an actual facility.

[0098] In particular, by using the fluid analysis unit 623 of this embodiment, it is possible to reproduce the flow field outside the analysis domain (upstream part of the trough) when the analysis domain is optimized, so analysis can be completed in a short time. Furthermore, by using an analysis model, the bilateral symmetry of the analysis results is improved, so high analysis accuracy can be achieved. Furthermore, if the fluid analysis unit 623 analyzes the location and speed at which water falling from the orifice lands on the water surface in the trough, this can contribute to improving the analysis accuracy.

[0099] Furthermore, when performing the above-mentioned analysis using CFD analysis, it is possible to use the 3D general-purpose thermal fluid analysis software "Phoenics," or other similar software such as "Ansys Fluent," "SOLIDWORKS Flow Simulation," "Particleworks," or "Autodesk CFD."

[0100] The configurations described in the above embodiments can contribute to improving the efficiency of water purification treatment at water purification plants. Such effects also contribute to achieving, for example, Goal 6 of the Sustainable Development Goals (SDGs) advocated by the United Nations, "Ensure availability and sustainable management of water and sanitation for all."

[0101] [Appendix 1] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0102] [Appendix 2] A water collecting trough mechanism according to a first aspect of the present invention includes a water collecting trough and a baffle installed in a flow path of the water collecting trough and having a wall surface installed so as to block a part of the flow of water through the flow path. According to the first aspect, the water collected in the water collecting trough is baffled by the baffle, causing turbulence in the water flow, so that additives added to the collected water can be efficiently dispersed within the flow path of the water collecting trough.

[0103] The water collecting trough mechanism according to a second aspect of the present invention can be configured in the first aspect, wherein the water collecting trough includes an inlet portion for water to enter the flow path and an outlet portion through which water that has flowed through the flow path flows out of the flow path, and the inlet portion is an orifice provided on a side surface of the flow path, an upper end of the side surface of the flow path, or a notch provided on the upper end of the side surface of the flow path. According to the second aspect, water can flow into the flow path of the water collecting trough through the side surface of the water collecting trough.

[0104] The water collecting trough mechanism according to a third aspect of the present invention is the water collecting trough mechanism of the first or second aspect, wherein the wall surface of the baffle has a vertical surface and is inclined with respect to the extension direction of the flow path. According to the third aspect, the water flowing through the flow path of the water collecting trough can be effectively baffled, and additives added to the water can be efficiently dispersed.

[0105] A fourth aspect of the present invention is a water collecting trough mechanism according to the first or second aspect, which includes a first blocking fluid installed at a certain position in the flow path of the water collecting trough and a second blocking fluid installed upstream of the certain position in the flow path of the water collecting trough, wherein the wall surfaces of the first and second blocking fluids have vertical surfaces and are inclined with respect to the extension direction of the flow path, and the wall surface of the second blocking fluid has a bent portion on the upstream side of the flow path in a V-shape that opens toward the downstream side when viewed from above. According to the fourth aspect, water flowing through the flow path of the water collecting trough can be blocked and rectified by the second blocking fluid on the upstream side, and the rectified water can be blocked by the first blocking fluid. Additives added to the flow path in which such first and second blocking fluids are installed are efficiently dispersed.

[0106] A fifth aspect of the present invention provides a simulation method executed by an apparatus for simulating the dispersibility of an additive in a water collection trough mechanism including a water collection trough and a baffle installed in a flow path of the water collection trough so as to partially block the flow of water through the flow path, the simulation method including the steps of: acquiring (a) water collection trough information indicating the shape of the water collection trough; (b) baffle information indicating the shape and location of the baffle; (c) fluid information indicating the state of the fluid flowing through the water collection trough; and (d) additive information indicating the type of additive to be injected into the water collection trough and the method of injecting the additive into the water collection trough; and generating, based on the water collection trough information, the baffle information, the fluid information, and the additive information acquired in the acquisition step, data indicating the dispersion status of the additive in at least a portion of a simulation target area downstream from the installation position of the baffle in the water collection trough. According to the fifth aspect, the additive dispersibility effect of the baffle can be quickly verified.

[0107] A simulation method according to a sixth aspect of the present invention may be configured in the fifth aspect such that, in the generation step, the data indicating the dispersion state of the additive is calculated to include at least one of (i) a concentration of the additive in at least a portion of the region, (ii) a velocity component of the additive flowing in at least a portion of the region, and (iii) a dispersion value indicating the dispersion state of the additive in at least a portion of the region.

[0108] The simulation method according to a seventh aspect of the present invention may be configured in the fifth or sixth aspect, further comprising a fluid analysis step of analyzing information on a fluid supplied to the water collecting trough to generate the fluid information. According to the seventh aspect, since the dispersibility can be analyzed by the fluid analysis step, it is possible to analyze the dispersibility effect with higher accuracy. [Example]

[0109] An embodiment of the present invention will now be described.

[0110] Example 1 In order to confirm the dispersibility of the additive in the water collecting trough 1 by the water collecting trough mechanism 50 of the above-described first embodiment, the following water collecting trough mechanism 50 was prepared as an experimental scale.

[0111] Dimensions of water collection trough 1: Flow path length 4,000mm x flow path width 200mm x height from bottom 300mm Number of orifices installed: On each of the sides 12a and 12b, there are 48 holes with a diameter of 21 mm along the length of the flow channel.

[0112] Additives: Coloring PAC with food coloring Additive location: Located 700mm upstream from the downstream end 1c.

[0113] Location of the blocking fluid 3 in the collecting trough 1: The upstream end of the blocking fluid 3 is located 400 mm upstream from the downstream end 1c. (The distance from the additive addition point to the upstream end of the blocking fluid 3 is 300 mm.) Flow rate: The height of the water surface near the blocking fluid 3 (height from the bottom of the water collection trough 1) is 75 mm Flow velocity 0.4m / sec.

[0114] The size of the blocking fluid 3 is shown in FIG.

[0115] For the experimental scale water collection trough mechanism 50 described above, a CFD analysis was performed, and the dispersion value was calculated by the CFD analysis, and the dispersion value was calculated by measuring absorbance.

[0116] To calculate the dispersion value from absorbance measurements, the water that had flowed to the downstream end 1c of the water collection trough 1 (water in which the colored PAC was dispersed) was divided into five regions along the width of the flow path 1a, and water was taken from each region. The absorbance of the water sample taken from each region was measured using a spectrophotometer (UVmini-1240 ultraviolet-visible spectrophotometer, manufactured by Shimadzu Corporation), and the concentration was converted using a calibration curve. The absorbance wavelength was set to 212.0 nm, which is the peak wavelength of the absorption spectrum of the colored PAC.

[0117] The spectrophotometer specifications are as follows: Measurement wavelength range: 190~1100nm Wavelength accuracy: ±1.0nm Wavelength setting repeatability: ±0.3nm Photometry: Single beam Photometric range: -0.3~3.0Abs.

[0118] The variance was calculated using the above formula (1).

[0119] As a comparative example, a water collection trough was prepared under the same conditions except that the blocking fluid 3 was not installed, and CFD analysis was performed, and the dispersion value was calculated by CFD analysis, and the dispersion value was calculated by absorbance measurement.

[0120] FIG. 12 shows an image of the results of a CFD analysis of the water collection trough mechanism 50 of this embodiment, the calculation of the variance value by the CFD analysis, an image taken from an obliquely upward perspective looking down from the downstream side to the upstream side of the water collection trough 1, and the calculation of the variance value by absorbance measurement. Note that in the analysis image of the CFD analysis, the upper side of the image represents the water surface, and the lower side represents the water depth. The variance value calculated by the CFD analysis was 0.084. The variance value calculated by the absorbance measurement was 0.062. It can be said that these variance values ​​are correlated with each other.

[0121] Here, the variance value calculated by the CFD analysis of the comparative example was 0.484, and the variance value calculated by the absorbance measurement of the comparative example was 0.635.

[0122] The above results show that the dispersion value is significantly lowered by the water collecting trough 1 of the example (water collecting trough mechanism 50) compared to the comparative example. This shows that the water collecting trough 1 of the example (water collecting trough mechanism 50) improves the dispersibility of the additive.

[0123] Example 2 The dispersibility of the additive in the water collecting trough 1 of the water collecting trough mechanism 50A (FIG. 5) of the above-described second embodiment was confirmed. In this example 2, an experimental-scale water collecting trough mechanism 50A was prepared in which the baffling fluid 3 of the experimental-scale water collecting trough mechanism 50 shown in example 1 was replaced with a baffling fluid 3A (FIG. 5). The dispersion value was calculated using the method described in example 1. The results are shown in FIG. 13 and will be described later.

[0124] Example 3 The dispersibility of the additive in the water collecting trough 1 of the water collecting trough mechanism 50B (FIG. 6) of the above-described third embodiment was confirmed. In this example 3, an experimental-scale water collecting trough mechanism 50B was prepared in which the baffle fluid 3 of the experimental-scale water collecting trough mechanism 50 shown in example 1 was replaced with a baffle fluid 3D (FIG. 6). The dispersion value was calculated using the method described in example 1. The results are shown in FIG. 13 and will be described later.

[0125] Example 4 The downstream baffle 3 of the water collecting trough mechanism 50B (FIG. 6) of the above-mentioned embodiment 3 was changed to the baffle 3A of embodiment 2 (FIG. 5), and the dispersion of the additive in the water collecting trough 1 was confirmed using an experimental scale water collecting trough mechanism equipped with a combination of an upstream baffle 3D and a downstream baffle 3A. The dispersion value was calculated using the method described in Example 1.

[0126] Fig. 13 shows images taken from above the downstream side of the water collecting trough toward the upstream side in each of the water collecting trough mechanisms of Examples 2, 3, and 4, and calculations of dispersion values ​​by absorbance measurements. In Fig. 13, A shows the results for Example 2, B for Example 3, and C for Example 4.

[0127] All of the variance values ​​shown in FIG. 13 are significantly smaller than the variance value of 0.635 calculated by absorbance measurement in the comparative example described above, indicating that dispersibility is improved.

[0128] Example 5 As shown in the above examples, it was confirmed that the dispersibility of the additive was improved by the addition of an anti-flocculating agent. Therefore, in this example, the influence of the improved dispersibility on the aggregation effect was confirmed.

[0129] As in Example 1 described above, in order to confirm the effect of improving the dispersibility of additives in the water collection trough 1 by the water collection trough mechanism 50 of embodiment 1 on the coagulation effect, the following water collection trough mechanism 50 was prepared on a practical experimental scale.

[0130] Dimensions of water collection trough 1: Flow path length 4,000mm x flow path width 200mm x height from bottom 300mm Number of orifices installed: On each of the sides 12a and 12b, there are 48 holes with a diameter of 21 mm along the length of the flow channel.

[0131] Additives: PAC Additive location: Located 700mm upstream from the downstream end 1c.

[0132] In this embodiment, a water collecting trough mechanism 50B including the baffle 3 and the upstream baffle 3D shown in Fig. 6 was adopted. Specifically, as follows: The upstream end of the blocking fluid 3 is located 400 mm upstream from the downstream end 1c. The distance from the upstream end of the blocking fluid 3 to the downstream end of the upstream blocking fluid 3D located upstream is 300 mm. The distance from the downstream end to the upstream end of the upstream blocking fluid 3D is 90 mm. (The distance from the additive addition point to the upstream end of the upstream blocking fluid 3D is 300 mm.) Flow rate: The height of the water surface near the blocking fluid 3 (height from the bottom of the water collection trough 1) is 75 mm Flow rate 330L / min.

[0133] The size of the baffle 3 is the same as that of the baffle 3 (FIG. 11) in Example 1. The size of the upstream baffle 3D used is that shown in FIG.

[0134] Based on the above-described water flow experiment using the field-scale collection trough mechanism 50, an experiment was conducted to examine the effect of the presence or absence of a blocking fluid on the coagulation effect. The water used in the experiment was taken from a receiving well, which has a higher turbidity than the treated water from the coagulation sedimentation basin. The receiving well is a tank that stores water taken from a river. Hereinafter, the water from the receiving well will be referred to as "raw water." In water purification plants, water from the receiving well generally enters a coagulation sedimentation basin. Next, the water from the coagulation sedimentation basin enters a filtration basin. Next, the water from the filtration basin enters a purified water basin. In the following examples, water taken from the receiving well is passed through an experimental trough and then introduced into the filtration basin for filtration. Hereinafter, this filtered water will be referred to as "treated water."

[0135] In this example, the following [Experiment 1] and [Experiment 2] were carried out.

[0136] [Experiment 1] Evaluation of the coagulation effect with and without baffle fluid 3 In this experiment, we confirmed the influence of the presence or absence of a blocking fluid and the PAC injection rate on the coagulation effect. The experimental conditions are shown in Table (1). [Table 1]

[0137] The PAC injection rate was set at four injection rate ratios (150%, 100%, 75%, and 40%), with the actual injection rate at the water treatment plant (the actual injection rate at a working water treatment plant) set at 100%. The water flow time through the trough was 15 minutes for each condition.

[0138] The "raw water" and "treated water" were sampled, and the turbidity and particle count of each were measured. A well-known turbidity meter was used to measure the turbidity, and a particle counter was used to measure the particle count.

[0139] The number of samples under each condition was set to 3, and the turbidity removal rate and particulate removal rate were evaluated using the following formula, taking into account fluctuations in raw water turbidity.

[0140] Turbidity removal rate [%] = {1-(Treated water turbidity / Raw water turbidity)} x 100 Particle removal rate [%] = {1 - (number of particles in treated water / number of particles in raw water)} x 100

[0141] The results of Experiment 1 are described below.

[0142] [Experiment 2] Evaluation of filtration stability during long-term water flow In this experiment, water was passed through the filter for an extended period of time with the baffle fluid 3 installed, and the stability of the filtration was confirmed. The experimental conditions are shown in Table (2). Filtration operation was carried out for 8 hours per day, for 5 days (40 hours cumulative) without the baffle fluid installed, and for 10 days (80 hours cumulative) with the baffle fluid installed. During the experiment, backwashing was carried out whenever the water level in the experimental filter reached the specified value. Samples were taken of the "raw water" and "treated water," and the turbidity and particle count of each were measured. The behavior of the filtered water level and the duration of filtration were also recorded. [Table 2]

[0143] [Experimental Results] The results of the above-mentioned [Experiment 1] are shown in Figures 15 and 16. Figure 15 shows the turbidity of the raw water (graph A in the figure), the turbidity of the treated water (graph B in the figure), and the turbidity removal rate (graph C in the figure) for the presence or absence of blocking fluid and for each PAC injection rate ratio.

[0144] As shown in graph C of Figure 15, the turbidity removal rate was better when a blocking fluid was installed (condition "with") than when no blocking fluid was installed (condition "without").

[0145] Figure 16 shows the number of particles in the raw water (graph A in the figure), the number of particles in the treated water (graph B in the figure), and the particle removal rate (graph C in the figure) for each case with and without a blocking fluid and for each PAC injection rate ratio.

[0146] As shown in graph C of FIG. 16, the particle removal rate was better when a blocking fluid was installed (condition "with") than when no blocking fluid was installed (condition "without").

[0147] Figures 15 and 16 show that regardless of the level of raw water turbidity or particle count, the treated water turbidity was lower with the baffle fluid, confirming a higher coagulation effect. This can be said to be because the installation of the baffle fluid changed the flow field, improving the dispersibility of the chemicals and leading to an improvement in the turbidity removal rate. Note that raw water turbidity was lower only when the baffle fluid was not installed and the PAC injection rate was 75%, but this is because measurements were taken on a different day from the other conditions.

[0148] Next, the results of the above-mentioned [Experiment 2] are shown in FIGS.

[0149] Regarding the turbidity removal rate over a long period of water flow, shown in Figure 17, when a PAC injection rate of 150% without an interceptor was used, the rate remained above 85% throughout the water flow period. In contrast, when a PAC injection rate of 100% without an interceptor was used, there were frequent periods when the turbidity removal rate fell below 85%. On the other hand, when a PAC injection rate of 75% with an interceptor was used, the rate remained above 85% throughout the water flow period, similar to the 150% PAC injection rate without an interceptor. From this, it can be said that a 150% injection rate without an interceptor showed a stable coagulation effect, and that a 75% PAC injection rate with an interceptor showed a coagulation effect equivalent to that of a 150% PAC injection rate without an interceptor.

[0150] Regarding the particle removal rate over a long period of water flow as shown in Figure 18, the removal rate was always maintained at 98% or higher under all conditions. This shows that the installation of the blocking fluid improved dispersibility even under conditions where the PAC injection rate was 75%, and treatment comparable to that achieved with a PAC injection rate of 150% was possible.

[0151] From Example 5, it was confirmed that the installation of a fluid blocking device has the effect of improving the coagulation in the water purification process. [Explanation of symbols]

[0152] 1, 1A, 1B Water collection trough 1a Flow path 1b Upstream end 1c downstream end 3, 3A, 3D fluid barrier 5 Additive part 5a Addition point 11 Bottom 12a,12b side 12c,12d top end 14 Orifice 30, 30A, 30D Wall 31 Bottom 32 Convex part 33 Bend 50, 50A, 50B Water collection trough mechanism 60 Simulation Device 61 Storage section 62 Control Unit 63 Input / output section 623 Fluid Analysis Department 624 Acquisition Department 625 Generation part 100 Water purification facilities 120 Coagulation sedimentation pond 130 Outflow drain 140 Rapid filtration pond

Claims

1. a water collection trough; A blocking fluid is installed in the flow path of the water collecting trough and has a wall surface installed so as to partially block the flow of water flowing through the flow path; Equipped with A water collection trough mechanism characterized by:

2. The water collecting trough includes an inlet portion for water to enter the flow path and an outlet portion through which water that has flowed through the flow path flows out of the flow path, The inlet portion is an orifice provided on a side surface of the flow channel, an upper end of the side surface of the flow channel, or a notch provided on the upper end of the side surface of the flow channel.

2. The water collecting trough mechanism of claim 1.

3. The wall surface of the fluid blocking member has a vertical surface and is inclined with respect to the extension direction of the flow path.

3. The water collecting trough mechanism according to claim 1 or 2.

4. a first baffle fluid that is the baffle fluid and is installed at a certain position in the flow path of the water collecting trough, and a second baffle fluid that is the baffle fluid and is installed at a position upstream of the certain position in the flow path of the water collecting trough, the wall surfaces of the first and second baffles have vertical surfaces and are inclined with respect to the extension direction of the flow path, The wall surface of the second baffle has a bent portion on the upstream side of the flow path when viewed from above, and is V-shaped and open toward the downstream side.

3. The water collecting trough mechanism according to claim 1 or 2.

5. A simulation method performed by a device that simulates the dispersibility of an additive in a water collecting trough mechanism, the water collecting trough including a water collecting trough and a baffle fluid that is installed in a flow path of the water collecting trough and has a wall surface that is installed so as to partially block the flow of water flowing through the flow path, (a) water collecting trough information indicating the shape of the water collecting trough; (b) blocking fluid information indicating the shape and arrangement position of the blocking fluid; (c) fluid information indicating the state of the fluid flowing through the water collecting trough; (d) additive information indicating the type of additive to be injected into the water collection trough and the method of injecting the additive into the water collection trough; an acquisition step for acquiring a generating step of generating data showing the dispersion status of the additive in at least a part of a simulation target area, which is an area downstream from the installation position of the blocking fluid in the water collecting trough, based on the water collecting trough information, the blocking fluid information, the fluid information, and the additive information acquired in the acquiring step; A simulation method comprising:

6. In the generating step, the data indicating the dispersion state of the additive is (i) the concentration of the additive within the at least some region; (ii) a velocity component of the additive-containing fluid flowing through at least a portion of the region; and, (iii) a dispersion value indicating the dispersion state of the additive within the at least a portion of the region; Calculate at least one of 6. The simulation method according to claim 5.

7. a fluid analysis step of analyzing information about the fluid supplied to the water collecting trough to generate the fluid information; 7. The simulation method according to claim 5 or 6.

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