Stirring device for suspended matter-containing liquid and stirring method for suspended matter-containing liquid

Abstract

To provide a stirring device for a floating substance-containing liquid capable of uniformly dispersing a floating part in a liquid without entangling a thread-like algae on a rotary body by stirring the liquid in which the floating substance including the thread-like algae such as a container floats.SOLUTION: A stirring device for a liquid in which suspended matter stored in a container or the like is suspended includes an electric motor 16 on a substrate 12, a rotary shaft 18 connected to the electric motor 16, a cylindrical rotary body 20 connected to the rotary shaft 18, and a plurality of recessed grooves 28 formed on a bottom surface of the rotary body 20 radially from a rotation center in a side surface direction of the rotary body 20 so that the liquid is ejected from an opening of the side surface of the rotary body 20 when the rotary body 20 rotates. This device is provided with a float 22 for floating the substrate 12 above the liquid surface, and a position holding mechanism of a rod 24 and a buoyant body 26 for holding the substrate 12 at a prescribed position of the liquid surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an agitation device and an agitation method for a liquid containing suspended matter, which agitates a liquid containing suspended matter stored in a structure such as a container or moat, or in a closed area of ​​the sea or a lake. [Background technology]

[0002] When cultivating algae, such as Porphyra, in a closed tank, it is important to prevent uneven distribution of water quality within the tank and to prevent planktonic organisms from settling to the bottom of the tank in order to improve the efficiency of Porphyra cultivation. In addition to planktonic organisms, organic and inorganic suspended matter also floats in the tank, and an agitation system capable of smoothly agitating the liquid containing these suspended matter is required. As an example of such an agitation system, Patent Document 1 below proposes a water cultivator that has multiple plate-shaped paddle blades that spread out radially from a rotating shaft that is set perpendicular to the water surface. The paddle blades are shaped so that the vertical width of the paddle blades farther from the rotating shaft is narrower than the vertical width of the paddle blades closer to the rotating shaft. By rotating the paddle blades around the rotating shaft, the bottom water that rises at the wider paddle blades spreads toward the water surface at the narrower paddle blades, increasing contact between the bottom water and the outside air, thereby incorporating oxygen into the water and dissipating odors from the water. The drive mechanism that turns the paddle blades is floated on a float, and a balancer located around the float maintains overall balance. This tiller is held in place by a fixed rope with one end connected to a balancer, and by rotating multiple paddle blades, it circulates the entire water by creating a diffusion flow to the periphery on the water surface using centrifugal force and an upward flow from the bottom due to the suction force in the center as a result of the diffusion.

[0003] Furthermore, Patent Document 2 listed below discloses an agitation device for uniformly dispersing powder in a liquid, which comprises a disk-shaped main body perpendicular to a rotation axis, a plurality of flow passages radially provided on the lower side of the main body and open on the lower side, and a space provided in the lower center of the main body and communicating with each of the plurality of flow passages, the main body having a hole or shaft portion at its upper part for connecting with the rotation axis, each of the plurality of flow passages being a groove with a U-shaped cross section provided on the lower part of the main body, the depth of each of the plurality of flow passages being set in a range of 50 to 100% of the radius of the main body, and extending from the lower center of the main body towards the outer periphery of the main body with a substantially flat bottom. The rotating body has a wall surface parallel to the rotation axis, the radius of the space is set to be 40 to 60% of the radius of the main body, and the space is set to be at the same height as each of the plurality of flow paths, and when the main body is immersed in a fluid and rotated around the rotation axis, the fluid is ejected from the plurality of flow paths in a tangential direction to the outermost periphery of the main body and the fluid is continuously sucked up from the lower side of the main body into the space, the sucked up fluid forms a spiral flow, and the fluid ejected from the plurality of flow paths generates a suction flow from the upper side of the main body downward. This rotating body is used by being placed in the middle of a powder-containing liquid stored in a container. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6497847 [Patent Document 2] Patent No. 6169207 Summary of the Invention [Problem to be solved by the invention]

[0005] The water cultivator proposed in the aforementioned Patent Document 1 is capable of agitating liquid with a simple mechanism. However, when this water cultivator is used for cultivating Porphyra, there is a problem in that the rotating paddle blades may cut the filamentous Porphyra. Furthermore, the agitating rotor proposed in Patent Document 2 can agitate a powder-containing liquid to obtain a powder-dispersed liquid in which the powder is dispersed. However, because this agitating rotor is placed in the middle layer of the powder-containing liquid, a lower reflux occurs between the rotor and the bottom of the container, and an upper reflux occurs between the rotor and the surface of the powder-containing liquid, which can cause the powder in the powder-containing liquid to be insufficiently homogenized. Another problem is that filamentous algae, such as laver seaweed, tend to become entangled in the grooves of the agitating rotor.

[0006] The object of the present invention is to provide an agitation device and a agitation method for liquids containing floating matter that can solve the above problems and agitate liquids containing floating matter, including filamentous algae, stored in structures such as containers or moats, or in enclosed areas of the sea or lakes, and that can uniformly disperse the floating matter in the liquid without the filamentous algae becoming entangled in the rotating body. [Means for solving the problem]

[0007] The agitation device for liquids containing suspended matter that can achieve the above-mentioned object is an agitation device for liquids containing suspended matter that is stored in a structure such as a container or a moat, or in a closed area such as the sea or a lake, and comprises: a rotation drive member installed on a substrate; a rotation shaft that is connected at one end to the rotation drive member and is arranged approximately perpendicular to the surface of the liquid in which the suspended matter is suspended; a cylindrical rotor that is connected to the other end of the rotation shaft and is arranged to be rotatable; and a plurality of grooves formed on the bottom surface of the rotor that are formed radially from the center of rotation toward the side surface of the rotor, so that when the rotor rotates, the liquid is ejected from openings on the side surface of the rotor; The device is characterized by comprising a buoyancy member that floats the substrate above the liquid surface so that the upper surface of the rotating body is exposed above the liquid surface and the groove of the rotating body is positioned below the liquid surface, and a position holding mechanism that holds the substrate at a predetermined position on the liquid surface.

[0008] The depth of the groove is preferably 10 to 50% of the radius of the rotor.

[0009] The cross-sectional shape of the groove is preferably U-shaped, C-shaped, or trapezoidal, the width of which gradually increases from the bottom of the groove toward the bottom of the rotor.

[0010] It is preferable that three or more of the recessed grooves are formed.

[0011] It is preferable that an odd number of the recessed grooves are formed.

[0012] It is preferable that the position holding mechanism is provided with a position adjustment member between the substrate placed on the surface of the liquid and the edge or bottom of the structure, or the edge or bottom of the enclosed area of ​​the sea or lake, so that the rotating body can be reliably held in a predetermined position.

[0013] It is preferable that this position adjustment member be one or more buoyant bodies connected between the substrate or the buoyant member and the edge via an extendable or non-extendable rod member, one or more fixed wires stretched between the substrate or the buoyant member and the edge, or one or more anchors installed between the substrate or the buoyant member and the bottom surface.

[0014] The position control unit, in which the position holding mechanism includes a plurality of fans provided on the substrate or the buoyancy member and a drive unit that drives and rotates each of the fans, and a position measurement mechanism that measures the position of the substrate, and when a difference occurs between the current position of the substrate measured by the position measurement mechanism and a preset set position, selects one of the fans that can move the substrate in the direction of the set position and transmits a drive start signal to the drive unit when the difference between the current position of the substrate and the set position falls within the preset allowable range, and transmits a drive stop signal to the drive unit when the difference between the current position of the substrate and the set position falls within the allowable range, can automatically hold the position of the rotating body.

[0015] The agitation device for a liquid containing suspended matter according to the present invention can be applied to a liquid containing suspended matter in which the suspended matter includes floating aquatic plants.

[0016] The present invention can be suitably applied to a liquid containing floating matter, in which the floating aquatic plants include one or more of algae, seaweed, seaweed, waterweed, aquatic plants, and water sprouts of moss.

[0017] A method of stirring a liquid containing floating matter that can achieve the above-mentioned object is characterized in that the above-mentioned stirring device for a liquid containing floating matter is installed at a predetermined position on the surface of the liquid in which floating matter is floating and which is stored in a structure such as a container or moat, or in an enclosed area of ​​a sea or lake, and the buoyancy member floats the substrate above the liquid surface, and the rotating body is positioned so that its upper surface is exposed above the surface of the liquid and the groove is positioned below the liquid surface, thereby simultaneously generating a flow from the surface of the liquid to the bottom of the structure, the enclosed area of ​​the sea or lake, and a flow from the bottom to the liquid surface, thereby stirring the liquid. [Effects of the Invention]

[0018] The stirring device for liquids containing floating matter according to the present invention can efficiently stir liquids containing floating matter, and in particular, even when stirring liquids containing floating matter including filamentous algae, the floating parts can be stirred without the filamentous algae becoming entangled.Furthermore, it is possible to simultaneously generate a flow from the liquid surface to the bottom of a structure, sea or enclosed area of ​​a lake, and a flow from the bottom to the liquid surface, thereby preventing floating matter from settling on the bottom of a structure, sea or enclosed area of ​​a lake, and achieving uniform water quality. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a perspective view showing an example of an agitation device for a liquid containing suspended matter according to the present invention. [Figure 2] 2A and 2B are a bottom view and a side view of the rotating body 20 shown in FIG. [Figure 3] 2 is an oblique view showing the state in which the stirring device for liquid containing suspended matter shown in FIG. 1 is attached to a container, an explanatory diagram explaining the stirring function using a rotor, and an explanatory diagram explaining the state of water flow within the container. [Figure 4] FIG. 10 is a bottom view of another rotating body to which the present invention is applied. [Figure 5] FIG. 10 is a side view of another rotating body to which the present invention is applied. [Figure 6] 1 is an explanatory diagram illustrating a state in which an agitation device for a liquid containing suspended matter according to the present invention is installed in a large aquaculture tank. FIG. [Figure 7] FIG. 1 is an explanatory diagram illustrating the state in which an agitation device for a liquid containing suspended matter according to the present invention is installed in a moat. [Figure 8] FIG. 10 is a perspective view showing another example of an agitation device for a liquid containing suspended matter according to the present invention. [Figure 9] 9 is an explanatory diagram for explaining the configuration of a control unit 60 shown in FIG. 8. FIG. [Figure 10] 9 is a flowchart for explaining a control method performed by the control unit 60 shown in FIG. 8. [Figure 11] FIG. 10 is a diagram showing the flow velocity distribution on the water surface in a simulation of the water flow in a cylindrical water tank using the agitator for liquid containing suspended matter according to the present invention. [Figure 12]FIG. 10 is a diagram showing the flow velocity distribution on the water surface in a simulation of the water flow in a cylindrical water tank using another stirring device for liquid containing suspended matter according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] An example of an agitation device for a liquid containing suspended matter according to the present invention is shown in FIG. 1. FIG. 1 is a perspective view of an agitation device 10 for a liquid containing suspended matter (hereinafter referred to as agitation device 10), in which an electric motor 16 serving as a rotational drive member is mounted on a four-legged base 14 on one side of a substrate 12. A battery serving as a power source for driving the electric motor 16 is omitted from FIG. 1. A rotating shaft 18 is connected at one end to the electric motor 16, penetrates the substrate 12, and has the other end connected to a cylindrical rotating body 20. Four floats 22 are attached to the other side of the substrate 12. As will be described later, these four floats 22 are buoyant members that float the substrate 12 above the surface of the liquid being agitated. Furthermore, a buoyant body 26 is attached to each of the four floats 22 via a rod member 24. As will be described later, when the agitator 10 is used to agitate the liquid stored in a container, the buoyant body 26 contacts the rim of the container to position the agitator 10 and to prevent the substrate 12 from rotating when the rotor 20 is rotated. The rod member 24 shown in Fig. 1 may be extendable so as to easily accommodate changes in the size of the container.

[0021] The rotor 20 of the agitator 10 shown in FIG. 1 has four grooves 28 formed on its bottom surface, radiating from the center of rotation of the rotor 20 toward the side, as shown in FIG. 2(a), with openings formed on the side of the rotor 20, as shown in FIG. 2(b). The cross-sectional shape of the grooves 28 is U-shaped, as shown in FIG. 2(b), and the ratio of the depth d of the grooves 28 to the radius r of the rotor 20 ((d / r) × 100(%)) is preferably 10 to 50%, and particularly preferably 10 to 40%. Agitators 10 equipped with rotors 20 having this ratio of less than 10% tend to be less effective at agitating liquids containing suspended matter, including filamentous algae. Agitators 10 equipped with rotors having this ratio of more than 50% tend to cause the filamentous algae to become entangled in the grooves 28 when agitating liquids containing suspended matter, including filamentous algae. However, a rotating body 20 with a ratio (d / r) of more than 40% and less than 50% has a lower rotation speed than a rotating body 20 with a ratio (d / r) of 10 to 40%, thereby preventing thread-like algae and the like from becoming entangled in the grooves 28. The ratio of the width to the depth of the groove 28 (width:depth) is preferably 1:1 to 3:1.

[0022] The agitator 10 shown in Figures 1 and 2 is mounted in a container 30 containing a liquid 32 containing floating matter, including filamentous algae, non-filamentous organisms, and particles, as shown in Figure 3(a). As shown in Figures 3(a) and 3(c), the agitator 10 mounted in the container 30 has a substrate 12 floated above the surface of the liquid 32 by four floats 22, and a rotor 20 connected to a rotation shaft 18 substantially perpendicular to the surface of the liquid 32 has its upper surface exposed above the surface of the liquid 32 and its groove 28 located below the surface of the liquid 32. The outer peripheral surfaces of buoyant bodies 26 mounted on the tips of rod members 24 connected to each of the four floats 22 abut against the inner edge of the container 30, thereby positioning the agitator 10 and preventing the substrate 12 from rotating when the rotor 20 is rotated.

[0023] As shown in Figures 3(a) and 3(c), when the rotor 20, whose upper surface is exposed above the surface of the liquid 32 and whose grooves 28 are located below the surface of the liquid 32, is rotated by the electric motor 16 in the direction of arrow A as shown in Figure 3(b), the liquid in the grooves 28 also rotates along with the rotor 20. At this time, centrifugal force acts on the liquid in the grooves 28 in proportion to the rotation speed, and as shown by arrow B in Figure 3(b), the liquid is ejected in a tangential direction from the openings of the grooves 28 that open at the outermost periphery of the rotor 20. At this time, at the portion where the grooves 28 join, which corresponds to the rotation center of the rotor 20, pressure is reduced by the ejected liquid, and the liquid 32 is continuously sucked up from the underside of the rotor 20, causing a flow of the liquid 32 toward the liquid surface.

[0024] 3(c), the liquid ejected in the tangential direction (arrow B) from the outermost periphery of the rotor 20 reaches the inner wall of the container 30, causing a flow toward the bottom of the container 30, which connects with a flow toward the liquid surface of the liquid 32. In this way, a flow from the surface of the liquid 32 to the bottom of the container 30 and a flow from the bottom of the container 30 to the surface of the liquid 32 occur simultaneously, creating a circulating flow that circulates the entire liquid 32, making it possible to agitate the entire liquid 32 and to homogenize the water quality while preventing suspended matter from settling on the bottom of the liquid 32.

[0025] As shown in FIG. 3(c), when the ratio ((d / r) × 100(%)) of the depth d of the grooves 28 to the radius r of the rotor 20 is 10 to 50%, the filamentous algae 34, which are suspended matter contained in the liquid 32, can be uniformly dispersed in the liquid 32 without becoming entangled in the grooves 28, which is preferable. This is presumably because, while suspended matter particles 36 are sucked into the grooves 28, the filamentous algae 34 are stirred without being sucked into the grooves 28. However, a rotor 20 with a ratio (d / r) of more than 40% but not more than 50% rotates at a slower speed than a rotor 20 with a ratio (d / r) of 40% or less, thereby preventing the filamentous algae 34 from becoming entangled in the grooves 28.

[0026] The number of grooves 28 formed on the bottom surface of the rotor 20 is preferably three or more, and preferably three to seven. An odd number is particularly preferable. If there are an even number of grooves 28, as shown in FIG. 3(b), the liquid flow directions in a pair of grooves 28, 28 will be opposite to each other, which may result in a decrease in the flow speed of the liquid ejected from the grooves 28. In this regard, if there are an odd number of grooves 28, as shown in FIGS. 4(a) and 4(b), the liquid flow directions in a pair of grooves 28, 28 will not be opposite to each other, which may eliminate the risk of a decrease in the flow speed of the liquid ejected from the grooves 28. In addition, the cross-sectional shape of the groove 28 may be a U-shape as shown in Figures 1 to 3, as well as a trapezoidal shape as shown in Figure 5(a), which gradually widens from the bottom of the groove 28 toward the bottom of the rotating body 20, as shown in Figure 5(b).

[0027] The agitator 10 shown in Fig. 1 positions the substrate 12 and prevents it from rotating by using four buoyant bodies 26 that abut against the edge of the container 30, but when agitating liquid stored in a large aquaculture tank 40 as shown in Fig. 6, the substrate 12, which is floating above the liquid surface by multiple floats 22, can be connected to each edge of the aquaculture tank 40 by fixed wires 42 to position the substrate 12 and prevent it from rotating. An electric wire for transmitting power to drive the electric motor 16 of the agitator 10 can be attached to the fixed wires 42. Furthermore, when stirring the water stored in a trench 44 as shown in Figure 7, the substrate 12, which is floating on the water surface with multiple floats 22, can be connected to multiple anchors 46 lowered to the bottom of the trench 44 with ropes 48, thereby positioning the substrate 12 and preventing it from rotating.

[0028] In oceans or lakes where there is a current of seawater or lake water, the agitator 10 is used in a closed area that is enclosed with boards, sheets, etc. to prevent the current of seawater or lake water. In this case, it is preferable to use a fixed wire 42 shown in Fig. 6 or an anchor 46 shown in Fig. 7 to position the substrate 12 floating on the water surface with multiple floats 22 and prevent it from rotating.

[0029] In the agitator 10 shown in FIGS. 1 to 7, the substrate 12 is positioned and prevented from rotating by using the buoyant body 26 (FIG. 3), fixed wire 42 (FIG. 6), and anchor 46 (FIG. 7) via the rod member 24. However, FIG. 8 shows an agitator 50 that can position the substrate and prevent it from rotating without using these components. The agitator 50 has protrusions 52a, 52b, 52c, and 52d at each corner of a substantially rectangular substrate 52, and a buoyant body 54 is attached to each of the protrusions 52a, 52b, 52c, and 52d, thereby floating the substrate 52 above the liquid surface. An electric motor 56 is mounted on a four-legged base 55 in the center of the substrate 52 as a rotation drive member. One end of the electric motor 56 is connected to a rotation shaft that penetrates the substrate 52 and the other end is connected to a cylindrical rotor. The rotary shaft, one end of which is connected to the electric motor 56, and the rotor, the other end of which is connected to the rotary shaft, are the same as those shown in FIGS. 1 to 7, and therefore a detailed description thereof will be omitted.

[0030] Fans 58a, 58b, 58c, and 58d are provided on protruding portions 52a, 52b, 52c, and 52d of substrate 52 shown in Fig. 8. Fans 58a and 58c are attached to protruding portions 52a and 52c at opposing corners of substrate 52, facing in opposite directions, and fans 58a and 58c attached to protruding portions 52a and 52c at opposing corners are also attached in opposite directions. This is because driving one of the fans prevents substrate 52 from rotating together with electric motor 56, which rotates a rotor immersed in liquid, and the remaining three fans hold substrate 52 in a predetermined position.

[0031] The drive units that rotate and drive the fans 58a, 58b, 58c, and 58d, namely, electric fan motors 59a, 59b, 59c, and 59d, are controlled by a control unit 60 mounted on the circuit board 52. As shown in FIG. 9, the control unit 60 is composed of a central processing unit (CPU) 62, a memory 64, a position measurement mechanism 66, and a transmitting unit 68. The memory 64 stores the installation position of the circuit board 52 and the allowable range of positional deviation. The position measurement mechanism 66 also includes a gyro mechanism that detects the state of the circuit board 52 and a GPS mechanism that measures the current position. The transmitting unit 68 transmits a signal from the CPU 62 to each of the electric fan motors 59a, 59b, 59c, and 59d.

[0032] A flowchart of the control by the control unit 60 is shown in Figure 10. When the start button is pressed in step S10, the CPU 62 reads data on the set position and its tolerance range of the substrate 52 from the memory 64 (step S12), and drives the electric motor 56 to rotate the rotating body (step S13). Next, the CPU 62 reads data on the rotation of the substrate 52 from the gyro mechanism of the position measurement mechanism 66, and if it determines in step S14 that the substrate 52 is rotating, it selects a fan to stop rotation (step S15), and transmits a drive signal from the transmitter 68 to the electric fan motor of the selected fan (step S16). In this step S16, if the electric motor 56 is rotated in the direction of arrow C as shown in Figure 9, the fan 52a or 52c is driven to prevent it from rotating together with the substrate 52.

[0033] If the CPU 62 determines in step S14 that the substrate 52 is not rotating, it reads current position data from the GPS mechanism of the position measurement mechanism 66 in step S18 and calculates the difference between this and the set position of the substrate 52 stored in memory 64 (step S18). Furthermore, if the CPU 62 determines in step S19 that the difference calculated in step S18 is greater than the allowable range stored in memory 64, it selects a position correction fan (excluding a fan that is driven to prevent co-rotation of the substrate 52) that can move the substrate 52 to the set position in step S20, and transmits a drive signal from the transmitter 68 to the electric fan motor of the selected fan (step 22). If the CPU 62 determines in step S19 that the difference calculated in step S18 is equal to or less than the allowable range stored in memory 64, it transmits a signal from the transmitter 68 to stop driving the position correction fan (step 24). Next, in step S26, if it is determined that stirring should continue, the process returns to step S14. If it is determined that stirring should end in step S26, a drive stop signal is sent from transmitting unit 68 to all of the fans that are running (step S27), and a drive stop signal is also sent from transmitting unit 68 to electric motor 56 (step S28). Thereafter, the stirring end button is pressed to end stirring (step S30). [Example]

[0034] Examples of the present invention will be described in detail below, but the scope of the present invention is not limited to these examples.

[0035] Example 1 The stirrer 10 shown in Figure 1 was used. The stirrer 10 has a battery-powered electric motor 16 mounted on a four-legged base 14 on one side of a resin substrate 12. A rotating shaft 18 connected to the electric motor 16 and penetrating the substrate is connected to a cylindrical rotor 20 with a diameter of 6 cm. Four foamed polyurethane floats 22 are attached to the other side of the substrate 12. Furthermore, a foamed polyurethane buoyant body 26 is attached to each of the four floats 22 via a rod member 24. Four grooves 28 are formed on the bottom surface of the rotor 20, radially extending from the center of rotation of the rotor 20 in the lateral direction and opening to the side of the rotor 20. The cross-sectional shape of the grooves 28 is U-shaped, and the depth d of the grooves 28 is 1.2 cm. The ratio of the depth d to the radius r of the rotor 20 ((d / r) × 100(%)) is 40%. The overall diameter of the stirrer 10 is 40 cm.

[0036] This agitator 10 was installed in a transparent resin tank containing 30 L of water. The four floats 22 kept the substrate 12 afloat above the water surface, the top surface of the rotor 20 exposed above the water surface, and the grooves 28 of the rotor 20 were located below the water surface. Each of the buoyant bodies 26 was in contact with the inner wall surface near the edge of the resin tank, preventing the substrate 12 from rotating with it. 20 pieces of Sujiaonori (Porphyra sujiaonori), which had grown to a total length of 5 to 10 cm, were added as suspended matter to the water stored in the resin tank, and the rotor 20 was rotated at a rotational speed of 30 rpm to perform agitation. After 180 minutes of continuous agitation, the suspended matter was uniformly dispersed without the filamentous algae becoming entangled in the rotor 20.

[0037] Example 2 The cylindrical rotor 20 used in Example 1 was a rotor 20 with a diameter of 3 cm (ratio ((d / r) x 100 (%)) was 50%), and stirring was carried out in the same manner as in Example 1, except that the rotation speed was set to 15 rpm. When stirring was continued for 180 minutes, the filamentous algae did not become entangled in the rotor 20, and the floating matter was uniformly dispersed. However, when the rotation speed of the rotor 20 was set to 30 rpm, the filamentous algae became entangled in the rotor 20.

[0038] Example 3 A numerical simulation was conducted to examine the agitation of water by a rotor located near the water surface in the center of a cylindrical water tank with a diameter of 10 m and a depth of 1 m. The rotor is a 6 cm cylindrical rotor with seven grooves formed on its bottom surface, radiating from the center of rotation of the rotor 20 toward the side, and opening to the side of the rotor. The cross-sectional shape of the grooves is U-shaped, with a depth d of 2.4 cm. The ratio of the depth to the rotor radius r ((d / r) × 100(%)) is 40%. When the rotor was rotated at 30 rpm, a flow was generated across the entire water surface in 12 minutes and 30 seconds. The results of this numerical simulation are shown in Figure 11. Figure 11 shows the flow velocity distribution on the water surface. A pattern of islands with high flow velocity appeared near the center at 12 minutes and 30 seconds, indicating that a flow was generated across the entire water surface of the tank.

[0039] Example 4 A numerical simulation was performed in the same manner as in Example 2, except that the radius of the rotor in Example 2 was set to 10 cm and the depth d of the grooves was set to 4 cm (the ratio to the rotor radius r ((d / r) × 100(%)) was 40%). A flow occurred across the entire water surface at 10 minutes 00 seconds. As the rotor becomes larger, the mixing time is shortened. The results of this numerical simulation are shown in Figure 12. Figure 12 shows the flow velocity distribution on the water surface, and indicates that an island pattern with a fast flow velocity appeared near the center at 10 minutes 00 seconds, and a flow occurred across the entire water surface of the tank. It can be seen from Examples 3 and 4 that the mixing time of the tank is shortened by increasing the radius of the rotor. [Industrial Applicability]

[0040] The device for stirring a liquid containing suspended matter according to the present invention can also be used for the cultivation of seaweed such as laver, or for cleaning moats or enclosed areas of the sea. [Explanation of symbols]

[0041] 10, 50: agitator, 12, 52: substrate, 14, 55: base, 16, 56: electric motor, 18: rotating shaft, 20: rotating body, 22: float, 24: rod member, 26, 54: buoyancy body, 28: groove, 30: container, 32: liquid, 34: algae, 36: particles, 40: culture tank, 42: fixed wire, 44: trench, 46: anchor, 48: rope, 52a, 52b, 52c, 52d: extension, 58a, 58b, 58c, 58d: fan, 59a, 59b, 59c, 59d: electric motor for fan, 60: control unit, 62: CPU, 64: memory, 66: position measurement mechanism, 68: transmitter, A, B, C: arrow, r: radius

Claims

1. A stirring device for a liquid containing floating matter, which stirs a liquid containing floating matter stored in a structure including a container or a moat, or in a closed area of ​​the sea or a lake, a rotation drive member installed on a substrate; a rotation shaft connected at one end to the rotation drive member and arranged substantially perpendicular to the surface of the liquid in which the suspended matter is suspended; a cylindrical rotor connected to the other end of the rotation shaft and arranged rotatably; and a plurality of grooves formed on the bottom surface of the rotor, the grooves being formed radially from the center of rotation toward the side surface of the rotor, so that when the rotor rotates, the liquid is ejected from openings on the side surface of the rotor, An agitation device for a liquid containing suspended matter, characterized in that it comprises a buoyancy member that floats the substrate above the liquid surface so that the upper surface of the rotating body is exposed above the liquid surface and the groove of the rotating body is positioned below the liquid surface, and a position holding mechanism that holds the substrate at a predetermined position on the liquid surface.

2. 2. The agitator for a liquid containing suspended matter according to claim 1, wherein the depth of the groove is 10 to 50% of the radius of the rotor.

3. An agitation device for liquids containing suspended matter as described in claim 1, characterized in that the cross-sectional shape of the groove is U-shaped, C-shaped, or trapezoidal, gradually widening from the bottom of the groove toward the bottom of the rotating body.

4. 2. The agitator for a liquid containing suspended matter according to claim 1, wherein three or more of the grooves are formed.

5. 2. The agitator for a liquid containing suspended matter according to claim 1, wherein an odd number of said grooves are formed.

6. The stirring device for liquids containing suspended matter described in claim 1, characterized in that the position holding mechanism is provided with a position adjustment member between the substrate placed on the surface of the liquid and the edge or bottom of the structure, or the edge or bottom of the enclosed area of ​​the sea or lake.

7. The stirring device for liquids containing floating matter described in claim 6, characterized in that the position adjustment member is one or more buoyant bodies between the substrate or the buoyant member and the edge portion via an extendable or non-extendable rod member, one or more fixed wires stretched between the substrate or the buoyant member and the edge portion, or one or more anchors installed between the substrate or the buoyant member and the bottom surface.

8. the position holding mechanism includes a plurality of fans provided on the substrate or the buoyancy member, and a drive unit that drives each of the fans to rotate; The stirring device for liquids containing suspended matter, as described in claim 1, is characterized in that it is equipped with a position control unit that includes a position measurement mechanism that measures the position of the substrate, and when a difference occurs between the current position of the substrate measured by the position measurement mechanism and a preset set position, selects one of the fans that can move the substrate in the direction of the set position if the difference is greater than a preset tolerance range, sends a signal to the drive unit to start driving, and sends a signal to the drive unit to stop driving when the difference between the current position of the substrate and the set position reaches within the tolerance range.

9. 2. The agitation device for a liquid containing suspended matter according to claim 1, wherein the suspended matter includes floating aquatic plants.

10. 10. The stirring device for a liquid containing suspended matter according to claim 9, wherein the floating aquatic plants are one or more of algae, seaweed, seaweed, aquatic plants, and water sprouts of moss.

11. A method for stirring a liquid containing suspended matter, characterized in that the stirring device for a liquid containing suspended matter described in claim 1 is installed using the position holding mechanism at a predetermined position on the surface of the liquid in which suspended matter is floating and which is stored in a structure such as a container or moat, or in a closed area of ​​a sea or lake, and the buoyancy member floats the substrate above the liquid surface, rotating the rotating body which is positioned so that its upper surface is exposed above the surface of the liquid and the groove is positioned below the surface of the liquid, thereby simultaneously generating a flow from the surface of the liquid to the bottom of the structure, the closed area of ​​the sea or lake, and a flow from the bottom to the liquid surface, thereby stirring the liquid.

Images