Saturated water generating device

Abstract

To provide a saturated water generator that can efficiently generate oxygen-saturated water in lakes, fish farms, sewage treatment plants, etc., with a simple configuration, and can sufficiently increase a dissolved oxygen concentration in the water.SOLUTION: A saturated water generator 1a of the present invention includes: a container 2 having an open top surface 2f and a bottom plate 2a with a rectangular shape in plan view and four side plates 2b that close a bottom surface 2c and side surfaces 2e; a water guide plate 3 that is bent so as to form such a shape that a part of an oval shape in side view is cut off, and is installed inside the container 2 with an opening (a part sandwiched between a pair of ends 3a, 3a) facing upward; a nozzle 4 for spraying water from above onto an inner surface 3b near the opening; a water supply pipe 5 connected to the nozzle 4 at a tip 5a; a water supply pump (not shown) having an outlet connected to a base end of the water supply pipe 5; and an overflow pipe 6 connected to a first drain port (not shown) provided in the side plate 2b near the bottom plate 2a.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an apparatus installed in lakes, fish and shellfish farms, sewage treatment plants, etc., for generating water in which the amount of dissolved oxygen has reached a saturated state (saturated water). In particular, the present invention relates to a saturated water generating apparatus capable of efficiently generating saturated water with a simple structure.

Background Art

[0002] Organic sludge present at the bottom of ponds, marshes, etc. is decomposed by microorganisms. However, if the amount of dissolved oxygen in the water is low, the organic sludge will be anaerobically decomposed, resulting in the generation of sulfides, methane gas, etc. To prevent the generation of these harmful substances, a technique for increasing the amount of dissolved oxygen in the water is required. Regarding this, several inventions and devices have already been disclosed. For example, Patent Document 1 discloses an invention related to an apparatus installed in water for the purpose of improving water quality by supplying oxygen to an oxygen-deficient water area, named "oxygen supply apparatus for water". The invention disclosed in Patent Document 1 has a structure including a dissolution tank installed in water and discharging the obtained oxygen-dissolved water to an arbitrary water depth layer, a pump that sucks water in an arbitrary water depth layer and supplies it to the dissolution tank, gas injection means for injecting a gas containing oxygen into the pumped-up water on the suction side or discharge side of this pump, and a float body arranged on the water surface of a lake or the like with the pump installed. According to such a structure, since the pump is installed near the upper part of the dissolution tank installed in water, the pressure of the dissolution tank can be increased using water pressure, and by refluxing the undissolved gas to the gas injection means, the effective utilization of the gas can be promoted.

[0003] Further, Patent Document 2 discloses an invention related to an apparatus named "deep aeration device" that is not affected by the differential pressure inside and outside the aeration body or the influence of floating substances and can surely perform emergency exhaust through an emergency exhaust pipe. The invention disclosed in Patent Document 2 includes an aeration body that is moored to the bottom of a lake such as a dam lake and circulates deep water near the bottom by aeration, an exhaust pipe and an emergency exhaust pipe installed above the aeration body, and a float valve installed at the lower end of the emergency exhaust pipe that moves up and down according to the fluctuation of the water level in the aeration body. The emergency exhaust pipe has its upper end provided near the outside of the aeration body, its lower end provided below the lower end of the exhaust pipe and below the normal water level of the air storage chamber in the aeration body. The float valve is structured to close the lower end of the emergency exhaust pipe by buoyancy during normal times when the water level is higher than the height of the lower end of the emergency exhaust pipe, and to open the lower end of the emergency exhaust pipe during abnormal times when the water level is lower than the height of the lower end of the emergency exhaust pipe. Since the invention disclosed in Patent Document 2 has a structure in which the valve in the aeration body is opened and closed by the rise and fall of the water level instead of a structure in which the valve is opened and closed by the differential pressure inside and outside, adjustment of the opening and closing pressure is not required. Therefore, emergency exhaust can be reliably performed. Also, since the float valve is arranged inside the aeration body, there is no risk of sediment and floating matter clogging the operating part, or floating matter such as fallen leaves and plastic bags blocking the opening of the valve, so emergency exhaust can be reliably performed.

[0004] Furthermore, Patent Document 3 discloses an invention related to a device named "underwater agitation aeration device" that is installed in a water tank such as a wastewater treatment facility and aerates the water in the tank while agitating it. The invention disclosed in Patent Document 3 includes a rotating cone that forms a downwardly flared bowl shape with the opening facing downward, a compressed air chamber formed inside the rotating cone, and a bottom rectifying plate arranged below the rotating cone with a flat upper surface and a disk shape. The vertical gap between the lower end of the peripheral edge of the opening of the rotating cone and the upper surface of the bottom rectifying plate, and a large number of narrow slits formed over the entire circumference of the peripheral edge of the opening of the rotating cone are used as the blowout ports for the compressed air stored in the compressed air chamber. According to such a structure, a large number of fine bubbles sheared by the rotational force of the rotating cone are generated, increasing the contact area with water, and thus improving the oxygen dissolution efficiency.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] The invention disclosed in Patent Document 1 has a structure in which water injected with oxygen by a gas injection means is supplied into a dissolution tank. However, with such a structure, the dissolved oxygen concentration in water cannot be sufficiently increased. Further, in FIG. 1 and the specification, as Example 1, it is described that the water ejected from the nozzle into the dissolution tank and colliding with the baffle plate foams violently, thereby increasing the gas-liquid contact surface area. However, it is also difficult to increase the dissolved oxygen concentration by foaming the water injected with oxygen. Further, although the invention disclosed in Patent Document 2 has the effect of being able to reliably perform emergency exhaust, the dissolved oxygen concentration in water cannot be efficiently increased only by aeration using a diffuser pipe. Furthermore, the invention disclosed in Patent Document 3 has a structure for generating and diffusing a large amount of fine bubbles. However, with the method of generating fine bubbles, it is difficult to sufficiently increase the dissolved oxygen concentration in water.

[0007] The present invention has been made in view of such conventional circumstances, and an object of the present invention is to efficiently generate water saturated with oxygen with a simple structure in lakes and marshes, fish and shellfish farms, or sewage treatment plants, etc., and to provide a saturated water generation device capable of sufficiently increasing the dissolved oxygen concentration in water.

Means for Solving the Problems

[0008] To achieve the above object, a saturated water generation device according to a first invention includes a container whose bottom surface and side surfaces are closed and a first drain port for discharging treated water is provided at the lower part, and a gas phase is formed at the upper part by a gas containing at least oxygen; a water guiding member installed in the container with its opening facing upward, and when viewing the inner surface following the opening from the side, the contour line forms a shape in which a part of an oval line is cut off; a nozzle for injecting water from above to the inner surface near the opening; a water supply pipe connected to the tip of this nozzle; and a water supply pump with a discharge port connected to the base end of this water supply pipe. The treated water is stored in the lower part of the container, which is a characteristic of this invention. Note that the oval line is also called a convex closed curve and is a single closed curve on a plane, defined as a curve such that for any line segment connecting two points inside, all points on that line segment are inside. However, the oval line in the first invention shall include a substantially oval line in which a part of the curve is replaced by a straight line. In the first invention, when water is ejected from the nozzle toward the inner surface near the opening of the water guiding member, this water descends along the inner surface of the water guiding member while entraining the gas forming the gas phase at the upper part of the container, then reverses at the lowermost part of the inner surface and rises again along the inner surface of the water guiding member. After that, the water and bubbles that reach near the opening of the water guiding member are partly pushed downward from the water guiding member by the water ejected from the nozzle, and the rest overflows from the opening of the water guiding member. Then, the water and bubbles pushed downward from the water guiding member descend along the inner surface of the water guiding member while entraining the above-mentioned gas again, then reverse and rise at the lowermost part, and near the opening, they are divided into the water and bubbles pushed downward from the water guiding member again by the water ejected from the nozzle and the water and bubbles overflowing from the water guiding member.

[0009] Thus, in the first invention, the water ejected from the nozzle entrains the oxygen-containing gas and repeatedly descends and ascends along the inner surface of the water guiding member, causing the inside of the water guiding member to be filled with bubbles. As a result, the amount of oxygen contained in the air dissolved in the water increases, and finally, water (saturated water) with a dissolved oxygen amount reaching a saturated state is generated. Also, the saturated water generated inside the water guiding member overflows from the opening and moves downward, and has the effect of being discharged as treated water from the first drain port to the outside of the container.

[0010] The second invention is characterized in that, in the first invention, it includes an air supply pipe for supplying gas into the container and a compressor connected to the base end of the air supply pipe. The container has its upper surface closed, and a water inlet, an air inlet, and an openable exhaust port are provided at the upper part. The water supply pipe and the air supply pipe are respectively inserted into the container with their tips through the water inlet and the air inlet. In the second invention, in addition to the action of the first invention, since the upper surface of the container is closed, by supplying air with a pressure higher than the atmospheric pressure into the container by the compressor, it has the effect of forming a gas phase with a pressure higher than the atmospheric pressure inside the container.

[0011] The third invention is characterized in that, in the second invention, the container is installed so that at least a part of it is submerged in water, and instead of providing the first drain port, the bottom surface is open, and the water supply pump is a submersible pump. In the third invention, in addition to the action of the second invention, by changing the depth of the water where the container is installed, the pressure of the gas phase formed inside the container changes, and the position of the gas-liquid interface is determined by the position of the exhaust port with respect to the container. Also, in the third invention, if the gas is continuously supplied into the container from the air supply pipe with the exhaust port open, the excess gas is discharged from the exhaust port and the gas inside the container is constantly replaced, and its composition is kept constant.

[0012] The fourth invention is characterized in that, in the third invention, there are provided a pressurized tank for a pump in which a submersible pump is housed, a first water supply passage installed in water so as to be parallel to the vertical direction, with the pressurized tank for the pump connected to the lower end and the upper end being open, a second water supply passage installed in water so as to be parallel to the horizontal direction, with the pressurized tank for the pump connected to one end, and a strainer connected to the other end of the second water supply passage. In the fourth invention, when the submersible pump is operated to supply water into the container through the water supply pipe, the inside of the pressurized tank for the pump becomes negative pressure. As a result, the water in the first water supply passage moves downward, and the water in the second water supply passage moves toward the pressurized tank for the pump. When the water in the second water supply passage moves, the water around the strainer is sucked into the second water supply passage. That is, in the fourth invention, in addition to the action of the third invention, as the water in the pressurized tank for the pump is sucked by the submersible pump, the water in the second water supply passage moves toward the pressurized tank for the pump, and as a result, the water around the strainer is sucked into the second water supply passage.

[0013] The fifth invention is characterized in that, in any one of the first to fourth inventions, the water guiding member is made of a bent plate material. In the fifth invention, in addition to the action of any one of the first to fourth inventions, the water guiding member has a simple structure and a low processing cost.

[0014] The sixth invention is characterized in that, in the first invention, instead of the container, there is provided a second drain port at the lower part for discharging treated water, a pressurized tank in which a gas phase is formed at the upper part by a gas containing at least oxygen and having a pressure higher than the atmospheric pressure, an air supply pipe for supplying gas into the pressurized tank, a compressor connected to the air supply pipe, and a drain pipe connected to the second drain port for discharging the treated water accumulated in the pressurized tank, and the water guiding member is installed in the pressurized tank with the opening facing upward. In the sixth invention, since the water-conducting member is installed inside the pressurized tank instead of the container, in addition to the operation of the first invention, it has the effect that it is easier to form a gas phase with a higher pressure than in the case of the second invention inside the pressurized tank and at the upper part inside the water-conducting member.

[0015] The seventh invention is characterized in that, in the sixth invention, the water-conducting member has a bent plate material and a pair of side plates that close both side surfaces of the plate material. In the seventh invention, in addition to the operation of the sixth invention, it has the effect that the structure of the water-conducting member is simple and the processing cost is low.

Effect of the Invention

[0016] According to the first invention, water saturated with oxygen (saturated water) can be efficiently generated, and the dissolved oxygen concentration in the water can be sufficiently increased. Further, since the structure of the first invention is simple, it can be manufactured at low cost. When the upper surface of the container is open, the pressure of the gas phase formed on the upper surface of the container becomes equal to the atmospheric pressure, and it is not necessary to make the container a pressure-resistant structure, so the manufacturing cost can be further reduced.

[0017] According to the second invention, in addition to the effect of the first invention, by ejecting water from the nozzle toward the inner surface of the water-conducting member near the opening in a state where a gas phase with a pressure higher than the atmospheric pressure is formed inside the container, it is possible to generate treated water with a higher dissolved oxygen concentration than in the case of the first invention in one pass.

[0018] In the third invention, since the pressure of the gas phase formed inside the container changes depending on the water depth at which the container is installed, a control mechanism or the like for keeping the pressure constant is unnecessary. Also, since the position of the gas-liquid interface is determined by the position of the exhaust port with respect to the container, a sensor for detecting the position of the gas-liquid interface is also unnecessary. Therefore, in addition to the effects of the second invention, there is an effect that the manufacturing cost is reduced. Further, in the third invention, if gas is continuously supplied into the container from the air supply pipe with the exhaust port open, the gas inside the container is constantly replaced and its composition is kept constant. As a result, the dissolved oxygen concentration of the treated water discharged from the container hardly fluctuates. Furthermore, since the bottom surface of the container is open and the same water pressure is applied to the inner and outer surfaces of the container, there is no need to make the container a pressure-resistant structure. Therefore, according to the third invention, the manufacturing cost is further reduced.

[0019] When the other end of the water supply pipe with a strainer attached to one end is connected to the suction port of the submersible pump, the range where the strainer can be installed is determined by the suction capacity of the submersible pump. For example, when the suction capacity of the submersible pump is low, the strainer has to be installed near the submersible pump. In contrast, in the fourth invention, when the water inside the pressurizing tank for the pump is sucked in by the submersible pump, as a result of the water in the second water supply path moving towards the pressurizing tank for the pump, regardless of the suction capacity of the submersible pump, the water around the strainer is sucked into the second water supply path. That is, in the fourth invention, in addition to the effects of the third invention, when installing the pressurizing tank for the pump and the second water supply path on the bottom of a pond or a marsh, etc., regardless of the suction capacity of the submersible pump, by installing the strainer at a location away from the submersible pump, there is an effect that a wide range of water can be treated. In addition, if the container is installed at the same height as the strainer at that time, the temperature difference between the low-layer water sucked from the strainer into the second water supply path and the treated water discharged from the container is small, and it is difficult for the treated water to mix with the middle-layer water or the upper-layer water. Therefore, it is possible to treat only the water in the low-layer water area.

[0020] According to the fifth invention, in addition to the effects of any one of the first to fourth inventions, since the structure of the water guiding member is simple and the processing cost is low, the manufacturing cost is reduced.

[0021] According to the sixth invention, in addition to the effect of the first invention, with a gas phase having a higher pressure than in the case of the second invention formed in the pressurized tank, water is ejected from the nozzle toward the inner surface of the water guiding member near the opening, whereby treated water with a higher dissolved oxygen concentration than in the case of the second invention can be generated in one pass. Further, in the sixth invention, the upper surface of the water guiding member is open, and since the pressure of the gas present inside is equal to the pressure of the gas forming the gas phase in the pressurized tank, it is not necessary to give the water guiding member a pressure-resistant structure similar to that of the pressurized tank. Therefore, according to the sixth invention, by making the structure of the water guiding member simple, it is possible to reduce the manufacturing cost.

[0022] According to the seventh invention, in addition to the effect of the sixth invention, since the structure of the water guiding member is simple and the processing cost is low, the manufacturing cost is reduced.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0024] The saturated water generation device of the present invention will be described with reference to Figs. 1 to 7. In the following description, assuming the state where the saturated water generation device is actually installed, expressions such as "upper end", "lower end", "bottom plate", and "bottom surface" are used.

Examples

[0025] Figs. 1(a) and 1(b) are a front view and a side view respectively showing the external appearance of a saturated water generation device 1a according to a first embodiment of the present invention. As shown in Figs. 1(a) and 1(b), the saturated water generation device 1a includes a container 2 whose bottom surface 2c and side surface 2e are closed by a bottom plate 2a having an opening on its upper surface 2f and having a rectangular shape in plan view and four side plates 2b, and a water guide plate 3 that is bent so as to have a shape in which a part of an oval line in side view is cut off and is installed inside the container 2 with the opening (the part sandwiched between a pair of end portions 3a, 3a, corresponding to the opening 9a shown in Fig. 4(a)) facing upward, a nozzle 4 that injects water from above onto the inner surface 3b near the opening, a water supply pipe 5 to which the nozzle 4 is connected at its tip 5a, a water supply pump (not shown) whose discharge port is connected to the base end of the water supply pipe 5, and an overflow pipe 6 connected to a first drain port (not shown) provided on the side plate 2b near the bottom plate 2a. The water guide plate 3 has both side surfaces closed by a pair of side plates 2b, 2b that are parallel to each other. Among the pair of side plates 2b, 2b perpendicular to the side surfaces, one of the inner surfaces 3b near the opening where water is sprayed by the nozzle 4 is installed inside the container 2 in an inclined state so as not to contact the side plate 2b far from the opening and with the upper side facing upward. The water guide plate 3 has a shape in which a part of the contour line is cut off from an oval line when the inner surface 3b following the above-mentioned opening is viewed in side view. It is desirable that the cut-off portion is the portion with the smallest radius of curvature within the oval line as shown in Fig. 1(a).

[0026] As shown by the arrow in Fig. 1(a), the water supplied from the water supply pipe 5 to the nozzle 4 accumulates at the lower part of the container 2. When the gas-liquid interface (water surface 7) reaches a predetermined height, it overflows from the open end 6a of the overflow pipe 6. Since the upper surface 2f of the container 2 is open and the atmosphere can freely enter and exit the inside, a gas phase is formed by the atmosphere in the upper part of the container 2 (the part above the gas-liquid interface). The overflow pipe 6 has the function of maintaining the water surface 7 inside the container 2 at a constant height so that a gas phase is formed in the upper part of the container 2 in the saturated water generation device 1a.

[0027] Fig. 2(a) is a schematic diagram for explaining the operation of the saturated water generation device 1a. In Fig. 2(a), the illustration of the side plate 2b arranged in front of the container 2 is omitted. In the saturated water generating device 1a, as indicated by the thin arrow, the water supplied to the nozzle 4 through the inside of the water supply pipe 5 is jetted toward the inner surface 3b near the opening with respect to the water guide plate 3, and while entraining the air forming a gas phase in the upper part of the container 2, it descends along the inner surface 3b of the water guide plate 3 from near one of the pair of end portions 3a, 3a (see Fig. 1(a)) as indicated by the thick arrow in Fig. 2(a), and then reverses at the lowermost part of the inner surface 3b and rises again along the inner surface 3b. Thereafter, part of the water and bubbles that have reached near the other of the pair of end portions 3a, 3a are pushed downward from the water guide plate 3 by the water jetted from the nozzle 4, and the rest overflows from the water guide plate 3. Then, the water and bubbles pushed downward from the water guide plate 3 descend along the inner surface 3b while entraining air again, then reverse at the lowermost part of the inner surface 3b and rise, and near the opening, they are separated into the water and bubbles pushed downward from the water guide plate 3 again by the water jetted from the nozzle 4 and the water and bubbles overflowing from the water guide plate 3. Thus, in the saturated water generating device 1a, the water jetted from the nozzle 4 repeatedly descends and rises along the inner surface 3b of the water guide plate 3 while entraining the air forming a gas phase in the upper part of the container 2, so that the inside of the water guide plate 3 is filled with bubbles. As a result, the amount of oxygen contained in the air dissolved in the water increases, and finally, water (saturated water) in which the amount of dissolved oxygen has reached a saturated state is generated.

[0028] The saturated water generated inside the water guide plate 3 overflows from the opening of the water guide plate 3 and then descends along the outer surface 3c (see Fig. 1(a)) of the water guide plate 3 and accumulates in the lower part of the container 2. Thereafter, when the water surface 7 of the saturated water accumulated in the lower part of the container 2 reaches a predetermined height, it is discharged as treated water (water treated inside the container 2) from the open end 6a of the overflow pipe 6. In this way, in the saturated water generator 1a, water saturated with oxygen (saturated water) can be efficiently generated, and the dissolved oxygen concentration in the water can be sufficiently increased. Further, since the saturated water generator 1a has a simple structure, it can be manufactured at low cost. Furthermore, in the saturated water generator 1a, the upper surface 2f of the container 2 is open, and the pressure of the gas phase formed inside is equal to the atmospheric pressure, so there is no need to make the container 2 have a pressure-resistant structure like the pressurized tank 8 described later. As a result, the manufacturing cost is further reduced.

[0029] FIG. 2(b) is a front view of a saturated water generator 1b according to a modified example of the saturated water generator 1a. As shown in FIG. 2(b), in the saturated water generator 1b, the tip 5a of the water supply pipe 5 and one end of the air supply pipe 16 are respectively inserted into the container 2 through a water supply port (not shown) and an air supply port (not shown) provided in the upper plate 2d that closes the upper surface 2f in the saturated water generator 1a. An exhaust pipe 17 is connected to an exhaust port (not shown) provided in the upper plate 2d, a compressor 18 is connected to the other end of the air supply pipe 16, and a solenoid valve 19a is installed in the exhaust pipe 17. According to such a structure, since the upper surface 2f of the container 2 is closed, air with a pressure higher than the atmospheric pressure can be supplied into the container 2 by the compressor 18. As a result, a gas phase with a pressure higher than the atmospheric pressure is formed inside the container 2. Therefore, by ejecting water from the nozzle 4 toward the inner surface 3b of the water guide plate 3 near the opening, treated water with a higher dissolved oxygen concentration than in the case of the saturated water generator 1a can be generated in one pass.

Example

[0030] FIG. 3(a) is an external view of a saturated water generator 1c according to the second embodiment of the present invention, and FIG. 3(b) is a cross-sectional view taken along the line A-A in FIG. 3(a). In order to avoid making the drawing complicated, only some fastening members are labeled in FIGS. 3(a) and 3(b). Also, for the components shown in FIGS. 1(a) and 1(b), the same reference numerals are used, and the description thereof is omitted as appropriate. As shown in FIGS. 3(a), 3(b), and 4(a), in the saturated water generation device 1c, a second drain port 20a from which treated water is discharged is provided at the lower part, and three water guiding members 9 are installed inside a pressurized tank 8 in which a gas phase is formed at the upper part by air whose pressure is higher than atmospheric pressure. The pressurized tank 8 is composed of a cylindrical tank body 10 provided with flanges 10a at both ends and installed so that the axial direction is horizontal, and a pair of cover bodies 11, 11 each provided with flanges 11a. The flange 10a of the tank body 10 and the flange 11a of the cover body 11 are connected using a fastening member 12 composed of bolts and nuts. The water guiding member 9 is composed of a water guiding plate 3 bent so as to have a shape in which a part of an oval line in a side view is cut off, and a pair of side plates 13, 13 that close both side surfaces of the water guiding plate 3, and is connected to the lower part of the side surface 8a of the pressurized tank 8 via a connector 14 with the opening 9a (see FIG. 4(a)) facing upward.

[0031] At the tips 5a (see FIG. 3(b)) of the three water supply pipes 5 inserted into the pressurized tank 8 through a water supply port (not shown) provided at the upper part of the pressurized tank 8, nozzles 4 that spray water downward from above are respectively connected to the inner surface 3b (see FIG. 3(b)) of the water guiding plate 3 in the vicinity of the opening 9a (see FIG. 4(a)). Also, at the base ends of the water supply pipes 5, the discharge ports of a water supply pump 15 are connected, and at an air supply port (not shown) and an exhaust port (not shown) provided at the upper part of the side surface 8a of the pressurized tank 8, one ends of an air supply pipe 16 and an exhaust pipe 17 are respectively connected. And a compressor 18 is connected to the other end of the air supply pipe 16, and a solenoid valve 19a is installed in the exhaust pipe 17. Also, a drain pipe 20 with a solenoid valve 19c installed is connected to the second drain port 20a. On the cover body 11 of the pressure tank 8, a water level sensor 21 for detecting the upper and lower water levels of the water accumulated inside and a control unit (not shown) for controlling the operation of the compressor 18 and the opening degree of the solenoid valve 19a based on the detection result of this water level sensor 21 are installed. That is, the saturated water generation device 1c has a structure that keeps the height of the water surface 7 constant by controlling the amount of gas supplied into the pressure tank 8 through the air supply pipe 16 and the amount of gas discharged from the pressure tank 8 to the outside through the exhaust pipe 17 based on the water surface 7 inside the pressure tank 8 detected by the water level sensor 21.

[0032] In the saturated water generation device 1c, different from the saturated water generation device 1b, since a water guiding member 9 is installed inside the pressure tank 8 instead of the container 2, a gas phase with a higher pressure than in the case of the saturated water generation device 1b can be easily formed inside the pressure tank 8 and above the water guiding member 9. And in this state, when water is ejected from the nozzle 4 toward the inner surface 3b near the opening 9a with respect to the water guiding plate 3 of the water guiding member 9, since the pressure of the above-mentioned gas phase is higher than that in the case of the saturated water generation device 1b, treated water with a higher dissolved oxygen concentration than in the case of the saturated water generation device 1b can be generated in one pass. Also, in the saturated water generation device 1c, the upper surface of the water guiding member 9 is open, and since the pressure of the air existing inside it is equal to the pressure of the air forming the gas phase at the upper part of the pressure tank 8, it is not necessary to make the water guiding member 9 have the same pressure-resistant structure as the pressure tank 8. That is, in the saturated water generation device 1c, since the water guiding member 9 can have a simple structure composed of the water guiding plate 3 and a pair of side plates 13, 13, the manufacturing cost can be reduced.

[0033] Figure 4(a) is an external perspective view of the water guiding member 9, and Figure 4(b) is an external perspective view of a modified example of the water guiding member 9. Also, Figure 4(c) is a cross-sectional view taken along the arrow B - B in Figure 4(b). As shown in Fig. 4(a), the saturated water generating device 1c includes a water guiding member 9 composed of a water guiding plate 3 and a pair of side plates 13, 13. The water guiding member 9 has a structure in which an opening 9a is formed by a portion surrounded by a pair of end portions 3a, 3a (see Fig. 1(a)) and the pair of side plates 13, 13. However, the saturated water generating device 1c is not limited to such a structure. For example, as shown in Figs. 4(b) and 4(c), the saturated water generating device 1c may have a structure including a block-shaped water guiding member 22 having a cavity 23 whose contour line forms a shape in which a part of an oval line is cut off when the inner surface 23b following the opening 23a is viewed from the side. In this case, the contour line of the inner surface 23b of the cavity 23 in the water guiding member 22 corresponds to the contour line of the inner surface 3b following the opening 9a in the water guiding plate 3 of the water guiding member 9. Note that not only the saturated water generating device 1c but also the saturated water generating devices 1a and 1b can have a structure in which the water guiding member 22 is installed inside the container 2 instead of the water guiding plate 3. However, when using the water guiding member 9 provided with the water guiding plate 3 instead of the water guiding member 22, since the structure is simple and the processing cost is low, there is an advantage that the manufacturing cost is reduced.

Embodiment

[0034] Fig. 5 is an external view of the saturated water generating device 1d according to the third embodiment of the present invention. Note that for the components shown in Figs. 1(a) and 1(b) and Figs. 3(a) and 3(b), the same reference numerals are used and the description thereof is appropriately omitted. As shown in Fig. 5, in the saturated water generating device 1d, instead of providing the first drain port (not shown) and the overflow pipe 6 in the saturated water generating device 1a, an exhaust pipe 24 with a solenoid valve 19b interposed is provided on the side plate 2b of the container 2 whose bottom surface 2c is open and at least a part of which is installed so as to be submerged in water. Further, a water supply port (not shown) and an air supply port (not shown) are provided on the upper plate 2d that closes the upper surface 2f of the container 2. The tip 5a of the water supply pipe 5 (see Fig. 2(b)) is inserted into the interior of the container 2 through the water supply port, and a compressor 18 is connected to the other end of the air supply pipe 16 whose one end is connected to the air supply port. Also, the discharge port of a submersible pump 26 to which electric power is supplied from an AC power supply 25 via a power cable 25a is connected to the base end of the water supply pipe 5, and a nozzle 4 that injects water from above is connected to the tip 5a of the water supply pipe 5 (see Fig. 2(b)) on the inner surface 3b of the water guide plate 3 in the vicinity of the opening 9a. If a pipe that branches from the air supply pipe 16 and leads to the cavity of the rotating mechanism of the motor of the submersible pump 26 is provided and air whose pressure has been increased by the compressor 18 is sent to the cavity through this pipe, it is possible to prevent a situation where surrounding water enters the cavity and the motor malfunctions. In this case, the submersible pump 26 does not have to be an expensive one with pressure resistance, so a general-purpose and inexpensive-structured one can be used as the submersible pump 26.

[0035] In the saturated water generating device 1d, when air pressurized to a pressure higher than atmospheric pressure using the compressor 18 is supplied from the air supply pipe 16 into the interior of the container 2 with the interior of the container 2 filled with water, a part of the water is pushed out from the bottom surface 2c, and as a result, the gas-liquid interface (water surface 7) moves downward, and a gas phase is formed in the upper part of the container 2. At this time, if the solenoid valve 19b is opened, when the gas-liquid interface reaches the exhaust port (not shown) to which the exhaust pipe 24 is connected, the air supplied from the air supply pipe 16 to the container 2 is discharged to the outside of the container 2 through the exhaust pipe 24. Therefore, the gas-liquid interface stays at the position of the exhaust port (not shown) to which the exhaust pipe 24 is connected without moving downward. As a result, the pressure of the gas phase formed inside the container 2 is kept constant at a state higher than the atmospheric pressure. For example, when the depth from the water surface 7 to the exhaust port (not shown) to which the exhaust pipe 24 is connected is 3 m, the pressure of the above-mentioned gas phase is about 30 kPa (gauge pressure).

[0036] In this way, in the saturated water generation device 1d, by changing the depth at which the container 2 is installed, the pressure of the gas phase formed inside the container 2 changes. Therefore, it is not necessary to install a control mechanism or the like for maintaining the gas phase at a constant pressure. Further, since the position of the gas-liquid interface is determined by the position of the exhaust port with respect to the container 2, a sensor for detecting the position of the gas-liquid boundary root surface is not required either. Thereby, the manufacturing cost is reduced. Furthermore, in the saturated water generation device 1d, if the air is continuously supplied from the air supply pipe 16 into the container 2 with the exhaust port open, the excess air is discharged from the exhaust port and the air inside the container 2 is always replaced. As a result, the composition of the gas phase inside the container 2 is kept constant, so that the dissolved oxygen concentration of the treated water discharged from the container 2 is hardly fluctuated. In addition, since the bottom surface 2c of the container 2 is open and the same water pressure is applied to the container 2 from the inside and the outside, it is not necessary to make the container 2 a pressure-resistant structure. Therefore, the saturated water generation device 1d has the merit that the manufacturing cost is reduced compared with the case of the saturated water generation device 1b.

Embodiment

[0037] FIG. 6 is an external view of a saturated water generation device 1e according to a fourth embodiment of the present invention. Note that the components shown in FIGS. 1(a) and 1(b), FIGS. 3(a) and 3(b), and FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. As shown in FIG. 6, the saturated water generation device 1e has, in the saturated water generation device 1d, a pressure tank 27 for a pump in which the underwater pump 26 is housed, a first water supply path 28 that is parallel to the vertical direction and is installed underwater with the pressure tank 27 for the pump connected to the lower end 28a and the upper end 28b open, a second water supply path 29 that is installed underwater parallel to the horizontal direction and has the pressure tank 27 for the pump connected to one end, and a strainer 30 connected to the other end of the second water supply path 29.

[0038] In the saturated water generation device 1e, when the underwater pump 26 is operated to supply water into the container 2 through the water supply pipe 5, the inside of the pressure tank 27 for the pump becomes negative pressure, so the water inside the first water supply path 28 moves downward and the water inside the second water supply path 29 moves toward the pressure tank 27 for the pump. Then, when the water inside the second water supply path 29 moves, the water around the strainer 30 is sucked into the inside of the second water supply path 29. When the other end of the water supply pipe with the strainer 30 attached to one end, like the second water supply path 29, is connected to the suction port (not shown) of the underwater pump 26, the installable range of the strainer 30 is determined by the suction capacity of the underwater pump 26. For example, when the suction capacity of the underwater pump 26 is low, the strainer 30 has to be installed near the underwater pump 26. In contrast, in the saturated water generation device 1e with the above structure, as the water inside the pressure tank 27 for the pump is sucked by the underwater pump 26, the water inside the second water supply path 29 moves toward the pressure tank 27 for the pump. As a result, the water around the strainer 30 is sucked into the second water supply path 29. That is, when the water inside the pressure tank 27 for the pump is sucked by the underwater pump 26, even if the strainer 30 is installed at a location far from the underwater pump 26, regardless of the suction capacity of the underwater pump 26, the water around the strainer 30 is sucked into the second water supply path 29. Therefore, the underwater pump 26 does not require a high suction capacity. Thus, in the saturated water generation device 1e, for example, even when the suction capacity of the underwater pump 26 is low, the strainer 30 can be installed at a location far from the underwater pump 26.

[0039] Thus, in the saturated water generation device 1e, when the pump pressurization tank 27 and the second water supply path 29 are installed on the bottom of a pond or a marsh, etc., regardless of the suction capacity of the submersible pump 26, by installing the strainer 30 at a location away from the submersible pump 26, a wide range of water can be treated. At that time, if the container 2 is installed at the same height as the strainer 30, the temperature difference between the lower layer water sucked from the strainer 30 into the second water supply path 29 and the treated water discharged from the container 2 is small, and it is difficult for the treated water to mix with the middle layer water or the upper layer water. Therefore, only the water in the lower layer water area can be treated. Further, during the operation of the submersible pump 26, since the water surface 28c inside the first water supply path 28 is in a state lower than the surrounding water surface 7, in the saturated water generation device 1e, by visually observing the height of the water surface 28c, the operating condition of the submersible pump 26 installed near the bottom of a lake or a marsh, etc. can be easily confirmed. Note that although FIG. 6 shows the container 2 constituting the saturated water generation device 1d shown in FIG. 5 as the container 2 constituting the saturated water generation device 1e, the container 2 of the saturated water generation device 1e can also use the container 2 constituting the saturated water generation device 1b shown in FIG. 2(b).

[0040] Table 1 shows the saturation amount of oxygen dissolved in distilled water at 1 atmospheric pressure for each temperature. However, the horizontal row represents the decimal part of the temperature, and the vertical row represents the integer part of the temperature. For example, when the temperature of the distilled water is 9.2 °C, the saturated dissolved oxygen amount (unit is mg / L) is the value (11.14) described in the column where 9 in the vertical row and 0.2 in the horizontal row intersect. Note that when the pressure of the oxygen in contact with the distilled water is 1.04 atmospheres (corresponding to a water depth of 0.4 m), the saturated dissolved oxygen amount is obtained by multiplying 11.14 by 1.04. Table 2 shows the theoretical values of the oxygen pressure thus obtained, the water depth and temperature (unit is °C) at which the pressure occurs, and the saturated dissolved oxygen amount (DO value: unit is mg / L). Further, the measured values in the table show the results of measuring the dissolved oxygen amount (DO value: unit is mg / L) in the treated water while changing the pressure of the air ejected from the nozzle 4 in the saturated water generation device 1b. Note that in the experiment, tap water is used instead of distilled water.

[0041]

Table 1

[0042]

Table 2

[0043] Figure 7 is a graph plotting the theoretical values and measured values shown in Table 2 for each water depth. Here, the horizontal axis represents the water depth, and the vertical axis represents the DO value (unit: mg / L). Also, the black circles represent the measured values, and the open diamonds represent the theoretical values. Figure 7 shows that in the saturated water generation device 1b, by simply supplying air adjusted to the atmospheric pressure at a desired water depth into the interior of the container 2 without using pure oxygen gas, saturated water corresponding to that atmospheric pressure is generated. In this case, since there is no need to use pure oxygen gas, the cost required for generating saturated water is reduced. That is, according to the saturated water generation device 1b, saturated water corresponding to the atmospheric pressure at a desired water depth can be generated easily and inexpensively. Note that the said effect in the saturated water generation device 1b is similarly exhibited also in the saturated water generation devices 1c to 1e capable of setting the air inside the water-conducting member 9 to a pressure higher than the atmospheric pressure.

Industrial Applicability

[0044] The present invention is applicable to cases where water is purified by increasing the amount of oxygen dissolved in water (DO value) in lakes and marshes, fish and shellfish farms, or sewage treatment plants, etc.

Explanation of Reference Numerals

[0045] 1a to 1e... Saturated water generating device 2... Container 2a... Bottom plate 2b... Side plate 2c... Bottom surface 2d... Upper plate 2e... Side surface 2f... Upper surface 3... Water guide plate 3a... End 3b... Inner surface 3c... Outer surface 4... Nozzle 5... Water supply pipe 5a... Tip 6... Overflow pipe 6a... Open end 7... Water surface 8... Pressure tank 8a... Side surface 9... Water guide member 9a... Opening 10... Tank body 10a... Flange 11... Cover body 11a... Flange 12... Fastening member 13... Side plate 14... Connector 15... Water supply pump 16... Air supply pipe 17... Exhaust pipe 18... Compressor 19a to 19c... Solenoid valve 20... Drain pipe 20a... Second drain port 21... Water level sensor 22... Water guide member 23... Hollow part 23a... Opening 23b... Inner surface 24... Exhaust pipe 25... AC power supply 25a... Power cable 26... Submersible pump 27... Pressure tank for pump 28... First water supply path 28a... Lower end 28b... Upper end 28c... Water surface 29... Second water supply path 30... Strainer

Claims

1. A container having a first drain port provided at the lower part thereof, where the bottom surface and the side surface are closed and treated water is discharged, and a gas phase is formed at the upper part by a gas containing at least oxygen; A water guiding member installed in the container with the opening facing upward, and when the inner surface following the opening is viewed from the side, the contour line thereof has a shape in which a part of an oval line is cut off; A nozzle for injecting water upward onto the inner surface near the opening; A water supply pipe connected to the tip of this nozzle; A water supply pump having a discharge port connected to the base end of this water supply pipe, comprising: The treated water is stored in the lower part of the container, The water guiding member is configured such that the water injected from the nozzle repeatedly rises and falls along the inner surface while entraining the gas forming the gas phase. A saturated water generating device characterized by this.

2. An air supply pipe for supplying the gas into the container; A compressor connected to the base end of this air supply pipe, comprising: The upper surface of the container is closed, and a water supply port, an air supply port, and an openable exhaust port are provided at the upper part, The saturated water generating device according to claim 1, wherein the water supply pipe and the air supply pipe are each inserted into the container with their tips through the water supply port and the air supply port.

3. A container having an upper surface and a side surface closed, a water supply port, an air supply port, and an openable exhaust port provided at the upper part, and installed so that at least a part thereof is submerged in water, and treated water is discharged from the open bottom surface, and a gas phase is formed at the upper part by a gas containing at least oxygen; A water guiding member installed in the container with the opening facing upward, and when the inner surface following the opening is viewed from the side, the contour line thereof has a shape in which a part of an oval line is cut off; A nozzle for injecting water upward onto the inner surface near the opening; A water supply pipe connected to the tip of this nozzle; A water pump with a discharge port connected to the proximal end of this water supply pipe, An air supply pipe for supplying the gas into the container, And a compressor connected to the proximal end of this air supply pipe. The water supply pipe and the air supply pipe are each inserted into the container with their respective distal ends through the water supply port and the air supply port. The water guiding member is configured such that the water jetted from the nozzle repeatedly rises and falls along the inner surface while entraining the gas forming the gas phase. A saturated water generating device characterized by this.

4. A pressurized tank for the pump in which the water pump is housed, A first water supply path installed in the water so as to be parallel to the vertical direction, with the pressurized tank for the pump connected to the lower end and the upper end open, A second water supply path installed in the water so as to be parallel to the horizontal direction, with the pressurized tank for the pump connected to one end, And a strainer connected to the other end of this second water supply path. The saturated water generating device according to claim 3, characterized by this.

5. The water guiding member is made of a bent plate material. The saturated water generating device according to any one of claims 1 to 4, characterized by this.

6. A pressurized tank provided with a second drain port at the lower part for discharging treated water, with a gas phase formed at the upper part by a gas containing at least oxygen and having a pressure higher than atmospheric pressure, An air supply pipe for supplying the gas into this pressurized tank, A compressor connected to this air supply pipe, A drain pipe connected to the second drain port for discharging the treated water accumulated in the pressurized tank, A water guiding member installed in the pressurized tank with the opening facing upward, and having a shape in which a part of an oval line is cut off when the contour line of the inner surface following the opening is viewed from the side. A nozzle that injects water from above onto the inner surface near the opening, a water supply pipe to which this nozzle is connected at its tip, and a water supply pump having a discharge port connected to the base end of this water supply pipe. The water guiding member is configured such that the water injected from the nozzle repeatedly rises and falls along the inner surface while entraining the gas in which the water forms the gas phase, and is a saturated water generating device characterized by this.

7. The saturated water generating device according to claim 6, wherein the water guiding member has a bent plate material and a pair of side plates that close both side surfaces of this plate material.

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