JP3641700B2 - Water quality improvement system for closed water areas - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a purification technique for purifying a closed water area by enlarging a water area used as a tap water source for the purpose of purifying anoxic water and polluted water areas in closed water areas such as lakes and dam lakes.
[0002]
[Prior art]
In recent years, in closed water areas such as lakes and dam lakes, pollutants such as earth and sand and domestic wastewater flow from rivers in the basin, and the eutrophication increases in the concentration of nitrogen and phosphorus in the water. Contamination of closed water is ongoing.
[0003]
Contamination causes include increases in inorganic substances such as sediment that flowed from river basins floating in water, large-scale generation of microorganisms (typically blue-green) associated with eutrophic value, microbes and small ones due to the progress of hypoxia A decomposition product of a fish carcass is considered, and it is assumed that it is possible to improve the water quality of the closed water area by removing these fine particle components of 100 μm or less floating in the water.
[0004]
The fine particle component that causes such contamination is not uniformly dispersed in water, but the fine particle component that is a contamination source dispersed by each water layer in the vertical distribution of the closed water area is different.
[0005]
The vertical distribution of a closed water area such as a dam lake can be roughly divided into five layers such as a surface near layer, upper layer, middle layer, lower layer, and bottom mud.
[0006]
The near-surface layer is a layer in which a large amount of phytoplankton such as sea lions is generated by photosynthesis. Phytoplankton has the effect of purifying water quality by taking in nitrogen, phosphorus, and the like together with carbon dioxide in water. However, when a large amount of phytoplankton such as blue sea urchins is generated, there is a problem that a strange odor such as a mold odor is generated and the appearance is further deteriorated. In addition, phytoplanktons such as blue seaweed generally have a short life span, so when these phytoplankton dies, they slowly settle from the layer near the surface and diffuse to the upper and middle layers, and promote the generation of spoilage bacteria in the upper and middle layers. Aerobic microorganisms that help to purify water in the upper and middle layers by promoting eutrophication, the spoilage bacteria generating carbon dioxide, reducing the amount of dissolved oxygen in the upper and middle layers, and proceeding with hypoxia There is a problem of threatening the survival of organisms such as small fish.
[0007]
The upper layer is a layer that serves as a tap water source, and is a layer that maintains a certain level of water quality, but in dam lakes, etc., the depth of the upper layer is said to be extremely shallow year by year. Some dam lakes have only 1m of upper water.
[0008]
The middle layer is a body of water where the dead sea cucumbers, small fish degradation products, microorganisms, etc. settle and float, and is a layer where hypoxia is progressing due to spoilage bacteria that have been produced on the carcasses such as sea cucumbers. In addition, fine clay particles that flowed in from the river basin are floating in the middle layer. Particle components derived from inorganic substances such as clay particles and organic particles such as dead bodies of blue-water remain, and turbidity ( TS) is a progressing layer. Particle components of inorganic and organic origin in the middle layer water are negatively charged in water and hydrated to form colloidal particles. These colloidal particles repel each other and become stable in water. Therefore, it does not settle down to the lower layer.
[0009]
During the conversion period in which there is a difference between the water temperature of the surface layer and the water temperature of the middle layer, the water temperature of the middle layer is higher than the water temperature of the surface layer. It is unlikely that the amount of dissolved oxygen in the water will increase and the survival of aquatic organisms will be threatened. However, especially in summer, the water temperature of the surface layer is high and the water temperature of the middle layer is low, so the vertical circulation of the closed water area is not performed, so the dissolved oxygen in the middle water is reduced, and the eutrophic value is advanced. The middle layer is poorly oxygenated and polluted, and the upper layer becomes shallower.
[0010]
In this way, particle components derived from inorganic substances and organic substances float in the upper water and middle water, and the oxygen-poor water and polluted water areas tend to expand. It is not limited to middle-layer water, and the anoxic water and polluted water areas change depending on the depth of the closed water areas such as dam lakes and lakes. The near-bottom layer of the closed water area where the water depth is shallow is not anaerobic like the lower layer described later, and the oxygen-poor water and polluted water area where inorganic and organic particle components floated are expanded to the bottom. It may become a layer.
[0011]
The lower layer is a water area where water pollution is further progressing, and it is an anaerobic condition in which dissolved oxygen is almost lost, and a layer containing a large amount of phosphorus, ammonia, methane, hydrogen sulfide, etc. It is considered.
[0012]
The bottom mud is the part where the dead carcass, clay, etc. that have settled in the water are finally deposited, and also contains a large amount of nitrogen, phosphorus, and other organic substances flowing from the river.
[0013]
The technologies for purifying closed water areas such as dam lakes include means for circulating the closed water areas up and down, means for aggregating suspended solids, means for removing organic matter by activating aquatic microorganisms by aeration, and mechanically removing bottom mud. Techniques using various means such as means for pumping and removing them are proposed.
[0014]
For example, in Japanese Patent Application Laid-Open No. 9-253698, an air lift pipe is provided in a cylindrical structure toward the bottom of the water, and oxygen-containing gas is supplied to aerate and flow the water while pumping up the bottom mud, A method of treating bottom mud has been proposed in which agglomerated particles are added to form agglomerated particles, and then aeration is stopped to allow suspended particles to settle on the water bottom.
[0015]
In Japanese Patent Laid-Open No. 9-314174, an apparatus main body arranged in a deep layer portion, an air supply means for supplying high-pressure air to the apparatus main body by a compressor or the like, a flow rate inside the apparatus main body, an inside of the apparatus main body, etc. A device that improves the dissolved oxygen concentration in the lower layer and bottom mud of the closed water area is proposed by means of a deep aeration device consisting of a means for measuring the dissolved oxygen concentration and a control means for controlling the air supply rate from the measured flow rate and dissolved oxygen concentration. ing.
[0016]
Further, in Japanese Patent Laid-Open No. 9-47749, at least a part of a closed water area is surrounded by a partition device, water intake means for taking water from the partitioned water area to be treated, water to be treated and filter medium taken up. A local water area comprising a filtration tank that is purified by contact and discharged as treated water; and a settling tank that flows out into a closed water area after settling floating substances present in the treated water discharged from the filtration tank A purification system has been proposed.
[0017]
[Problems to be solved by the invention]
However, in the bottom mud treatment method in which the flocculant is added and settled, the middle layer, the lower layer, and the bottom mud are disturbed by aeration flow. The upper layer water is temporarily contaminated and cannot be used as a tap water source. In addition, since the pollutants that have been agglomerated and settled by the flocculant are directly deposited as bottom mud, there is a problem that they are not a fundamental means for removing the pollutants.
[0018]
In the deep aeration apparatus, the lower layer water to be treated is aerated to increase the dissolved oxygen in the closed water area, which is a fundamental removal of suspended particle components in the middle layer water and the lower layer water. There is a problem that it is not. In addition, it is difficult to reduce the size of the bubbles released into the water in a high pressure state by the compressor as in the deep aeration apparatus, and the external pressure (water pressure) decreases as the bubbles rise in the water. For this reason, when the bubble diameter becomes larger and the bubbles become larger, the contact area between the bubbles contained in the unit volume and the water decreases, so that there is a problem that the fine particle component floating in the water is difficult to adhere to the bubbles.
[0019]
In the local water purification system, in order to supply a water purification plant from a closed water area such as a dam lake, it is necessary to surround and treat a part of the closed water area such as a dam lake with a partition device attached with a buoy. There is a problem that processing work becomes difficult. In addition, the local water purification system is not intended to purify a specific water layer in the vertical distribution of the closed water area, so the algae purification device (algae removal device) for purifying the surface vicinity layer, There is a problem that a plurality of devices such as a fluidized bed type purification device for purifying anaerobic conditions (ammonia nitrogen component) are required.
[0020]
Thus, in the conventional purification system, in the closed water area where the closed water area is divided into vertical distribution such as upper layer, middle layer, lower layer, purification of the near surface layer and upper layer, or lower layer and bottom mud is performed. Although there is a target, the upper layer used as a tap water source is expanded, and the target is focused on purifying middle-layer water in which inorganic and organic particulate components are floating and anoxic water and polluted water areas are expanding. There was no.
[0021]
Since the upper layer is a water area used as a tap water source, there is a demand for expansion of the upper water area. In order to expand the upper layer, in particular, oxygen-poor water and polluted water areas including the upper and middle layers used as a tap water source. Water quality improvement is required.
[0022]
If the dissolved oxygen in the closed water area is increased by aeration or aeration as in the prior art, the particulate component that becomes a contamination source in the middle layer, lower layer and bottom mud will be scattered to the surface near layer and the upper layer, There was a problem that phosphorus, ammonia, hydrogen sulfide, etc. in the lower layer and bottom mud were disturbed to the middle layer and upper layer.
[0023]
If the upper layer is contaminated by aeration or aeration, there is a problem that the upper layer water in the closed water area cannot be temporarily used as a tap water source, and has a great influence on the public.
[0024]
Therefore, in a closed water area with a deep water depth that can be divided into upper, middle, and lower layers, purification methods that disturb the pollutants in the bottom mud, middle layer, and lower layer to the upper layer and the surface near layer are as much as possible. Avoid and should build a purification system that will not contaminate the upper layer even temporarily.
[0025]
Furthermore, even in closed water areas such as shallow lakes that cannot be divided into upper, middle, and lower layers, pay attention to various pollution sources that cause anoxic water and polluted water in the closed water areas, and appropriate means for each pollution source. Therefore, an integrated purification system that totally separates and removes various pollution sources has not been constructed.
[0026]
Therefore, the present invention was devised in view of the various problems described above, and without disturbing the upper layer and the near-surface layer of a deep closed water area divided into an upper layer, a middle layer, and a lower layer, and relatively Even in shallow closed water areas, physical and biological treatments suitable for various sources of anoxic and polluted water in closed water areas should be carried out to improve the quality of the anoxic and polluted water areas in closed water areas. As a technical issue, the purpose is to provide a water quality improvement system for closed water areas that can expand the upper layers that need to maintain a certain level of water quality as a tap water source and purify poor oxygen water and polluted water areas. To do.
[0027]
[Means for Solving the Problems]
In order to solve the above technical problem,
The means of the invention described in claim 1 is a water quality improvement system for a closed water area that improves the anoxic water in a closed water area and the water quality in a polluted water area.
The first tank provided with the pumping means and the fine bubble generating means for generating fine bubbles from below, which pumps the oxygen-poor water and the polluted water as an upward flow, and the treated water that has flowed out of the first tank It flows as a downward flow with a flow rate slower than the flow rate of the upward flow of the tank, and has a function of separating the levitated matter and the sediment from the water to be treated. The second tank provided with the microorganism carrier and the treated water flowing out as a downward flow from the lower side of the second tank flowed out to the upper surface of the closed water area as an upward flow, and the sediment settled and separated in the second tank was deposited. And a third tank provided with a sediment removing means for removing the deposited sediment and a sediment removing means for removing the deposited sediment.
[0028]
In the first aspect of the invention, in the first tank provided with the pumping means and the fine bubble generating means, the suspended fine particles of inorganic / organic matter floating in the closed water area of the oxygen-poor water or the polluted water are caused. It is attached to fine bubbles and pumped up as an upward flow.
[0029]
The fine bubbles are bubbles of about 10 to 30 μm, and the surface area of the bubbles per unit volume is increased by such fine bubbles to increase the effect of adhering floating particles.
[0030]
In the first tank, the amount of pumped water is set to an amount that allows large particles that cannot adhere to fine bubbles to flow as an upward flow. To do.
[0031]
In the first tank, the levitated fine particles adhering to the fine bubbles and floating are separated from the water to be treated as levitated substances in the second tank and removed by the levitated substance removing means. As the floating substance removing means, for example, an adsorption filter, a separation membrane or the like can be used.
[0032]
In the second tank, since the downward flow flowing out from the first tank to the second tank is set to flow at a slower flow rate than the upward flow of the first tank, it adheres to the fine bubbles in the first tank. The fine particles can be surely floated on the water surface in the second tank and removed by the floating substance removing means.
[0033]
In addition, since the microbial carrier is provided in the second tank, the organic matter-derived fine particle components contained in the downward flow flowing slowly at a low flow rate are separated from the organic matter-decomposing bacteria, ammonia oxidizing bacteria, Biologically decomposed and removed by various microorganisms such as nitrate-reducing bacteria. In the second tank, dissolved oxygen in the water is increased due to the fine bubbles flowing in from the first tank, so that microorganisms are easy to live in and the environment of the microorganisms is active. improves. As the microbial carrier, for example, porous amorphous carbon, porous ceramics such as zeolite, fibers using carbon fibers, porous synthetic resins, and the like can be used.
[0034]
And the big particle which does not adhere to a fine bubble settles from the downward flow of a 2nd tank, and is isolate | separated from to-be-processed water. In the second tank, the sediment separated from the water to be treated is deposited on the sediment deposition means and removed by the sediment removal means. As the sediment removing means, for example, a suction pump for sucking the sediment and removing it from the sediment depositing means can be used.
[0035]
The treated water that has flowed into the third tank from the second tank becomes an upward flow in the third tank and is discharged to the closed water area. Thus, since the to-be-processed water is discharge | released as an upward flow, the big particle which settled in the to-be-processed water used as clarified water does not mix, and the 3rd tank has a function as a rectification tank. Yes.
[0036]
In the water quality improvement system consisting of the first tank, the second tank, and the third tank, the pollution in the anoxic water and polluted water is achieved by the complete treatment in the system without disturbing the surface layer and upper layer of the closed water area. The upper layer uses clear water with improved dissolved oxygen content as the source of tap water, effectively removing the organic and inorganic particulate components that cause pollution using physical and biological means. It is possible to expand the upper water area. In closed water areas such as shallow lakes that cannot be divided into upper, middle, and lower layers, the closed water area is not only expanded by performing the system-complete treatment in the present invention. It becomes possible to purify the whole.
[0037]
In addition to the structure of the invention described in claim 1, the means of the invention described in claim 2 is a method in which a part of the water to be treated that flows out of the first tank and flows into the second tank into the first tank and the second tank. A refluxing means for refluxing from the lower side to the first tank is provided.
[0038]
In the invention described in claim 2, since the reflux means is provided between the first tank and the second tank, the water to be treated is repeatedly circulated through the second tank, and the organism by the microorganisms supported on the microorganism carrier. It is possible to secure the residence time necessary for the treatment.
[0039]
According to a third aspect of the present invention, in the water quality improvement system for the closed water area according to the first or second aspect, the first tank is an inner cylinder having a length reaching the poor oxygen water and the polluted water area. Is provided on the outer periphery of the first tank, and is provided with a middle cylindrical body provided with a wall portion that is higher on the water surface than the wall portion of the first tank, and the third tank is provided on the outer periphery of the second tank. The outer cylindrical body is provided with a wall portion that is positioned lower on the water surface than the wall portion of the second tank.
[0040]
In the invention according to claim 3, in the first tank which is the inner cylinder, the water to be treated which has been raised by the pumping means overflows into the second tank provided on the outer periphery of the first tank, The fine particle components adhering to the fine bubbles surely float and separate from the water to be treated flowing into the second tank and overflowing in the second tank, and the water to be treated naturally flows in the second tank, which is an intermediate cylinder. By this, it becomes a downward flow with a slower flow rate than the upward flow of the first tank, slowly flows between the microbial carriers, and secures the time necessary for the biological decomposition process of the organic matter-derived fine particle components in the treated water, Large particles that do not adhere to fine bubbles from the water to be treated are easily settled.
[0041]
The treated water that has flowed out of the second tank collides with the third tank, which is an outer cylindrical body provided on the outer periphery of the second tank, and as a result of natural flow, it becomes an ascending flow with a slow flow velocity, and the settled particles are covered by the covered water. Without being mixed into the treated water, it is discharged to the upper layer of the closed water area as the treated water clarified from the third tank.
[0042]
Thus, because the first tank, the second tank and the third tank have a triple tank structure, it is designed as a compact water quality purification system in the tank without releasing the water to be treated during treatment to the outside. In addition, with the low operating power required for pumping water, the natural flow of treated water can be used to improve the quality of anoxic water and polluted water by physical and biological treatment. An energy-saving water quality improvement system with low operating costs can be provided.
[0043]
According to a fourth aspect of the present invention, there is provided the invention according to the third aspect, wherein the sediment depositing means is a closing plate that closes between a lower portion of the first tank and a lower portion of the third tank.
[0044]
In the invention according to claim 4, the sediment depositing means is a simple structure that closes the space between the first tank and the third tank, the sediment separated in the second tank, the middle layer water, It can be removed without mixing in the lower layer water.
[0045]
According to a fifth aspect of the present invention, in the invention according to the fourth aspect, the closing plate is inclined and a lower integrated portion is provided than other portions.
[0046]
In the invention of claim 5, since the closing plate which is the sediment depositing means is inclined and the accumulation portion lower than the other part is provided, the sediment deposited on the closing plate naturally falls. It collects in the accumulating part and the sediment can be easily removed. Note that the stacking unit is not limited to one place, and may be provided at a plurality of places.
[0047]
According to a sixth aspect of the present invention, in the third, fourth, or fifth aspect of the invention, the second tank is a conical middle cylindrical body that is reduced in diameter in the downward direction.
[0048]
In the invention of claim 6, since the second tank is a conical middle cylinder whose diameter is reduced in the downward direction, the surface area of the second tank is increased toward the upper part, and the first tank is changed to the second tank. The flow rate of the inflowing downflow can be reduced, and the area in which the fine bubbles float is increased, which is advantageous for the floating of the fine particles attached to the fine bubbles.
[0049]
Moreover, since the middle cylinder used as the second tank has a smaller surface area at the lower part and, conversely, the space between the third tank provided on the outer periphery of the second tank and the third tank, it flows out from the second tank to the third tank. The flow rate of the upward flow can be slowed down, which is advantageous for sedimentation of large particles.
[0050]
According to a seventh aspect of the present invention, in the first or second aspect of the present invention, the second tank is a tank that is continuous from the first tank in which the water to be treated pumped in the first tank is circulated by the head pressure. The third tank is a tank connected to the second tank.
[0051]
In the invention according to claim 7, since the first tank, the second tank and the third tank are configured to be continuous, and the treated water pumped up in the first tank is circulated by the head pressure, By utilizing the natural flow of water, it is possible to provide a water quality improvement system that realizes energy saving with low operating costs.
[0052]
The means of the invention described in claim 8 is that, in the invention described in claim 1, 2, 3, 4, 5, 6 or 7, a float is provided in the first tank, the second tank and the third tank. .
[0053]
In the invention according to claim 8, since the float for floating the first tank, the second tank and the third tank on the water surface is provided, the float is moved to an arbitrary position in a closed water area such as a dam lake by the float buoyancy. It is possible to improve the water quality of anoxic water and polluted water in a wide range of closed waters.
[0054]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of a water quality improvement system in a closed water area. FIG. 2 is an explanatory diagram showing a state in which a water quality improvement system is installed in a closed water area. In addition, the arrow in a figure has shown the flow direction of to-be-processed water.
[0055]
As shown in FIG. 1, the water quality improvement system 1 is a pumping device 7 that is a pumping unit for pumping up anoxic water and polluted water in a closed water area such as a dam lake, and a microbubble generating unit that generates microbubbles from below. A first tank 2 provided with a fine bubble generator 6; a second tank 3 that is a concentric middle cylinder with the first tank 2 provided on the outer periphery of the first tank 2; It is comprised from the 1st tank 2 and the 3rd tank 4 which are the concentric outer cylinders provided in the outer periphery.
[0056]
FIG. 3 is a flow diagram showing the means for purifying the oxygen-poor water and the polluted water area in each of the first tank 2, the second tank 3 and the third tank 4. Hereinafter, the purification means in each of the first tank 2, the second tank 3, and the third tank 4 will be sequentially described based on the drawings.
[0057]
The first tank 2 is an inner cylinder having a length that reaches the poor oxygen water and the polluted water area, and the pumping device 7 provided in the first tank 2 is driven from a drive unit provided with a motor, a speed reduction means, and the like. In this device, a shaft is suspended, screw wings are provided on the drive shaft, and the screw wings are rotationally driven to pump up oxygen-poor water and polluted water as an upward flow. The pumping device 7 is set so that a relatively large particle that cannot be attached to the fine bubbles is also lifted by the rising flow. The pumping device is not limited to the one in this example, and various types such as those using propeller blades, pumps, and the like can be used.
[0058]
The fine bubble generator 6 is a device that generates uniform fine bubbles (10 to 30 μm) and generates fine bubbles by taking in air from the water surface of the closed water area. Such microbubbles are, for example, 30 μm microbubbles, 33 times in surface area and 37,000 in the same volume as compared to 1 mm size bubbles. In addition, 10 μm fine bubbles are 100 times the surface area and 1,000,000 in the same volume compared to 1 mm size bubbles, increasing the solubility in water and increasing the surface area in contact with water. Therefore, it makes it easy to attach suspended particulates.
[0059]
Fine bubbles are generated from the lower side of the first tank 2 by the fine bubble generator 6, and the suspended fine particles originating from the inorganic substance and the organic substance floating in the poor oxygen water and the polluted water area are attached to the fine bubbles, or the pumping device 7. It is put on the upward flow formed by the above and floats to the vicinity of the water surface of the first tank 2.
[0060]
Moreover, since the fine bubbles are mixed with the water to be treated and pumped, the apparent specific gravity of the water to be treated is lowered, the driving force of the pumping device 7 is reduced, and the water can be pumped efficiently.
[0061]
The water to be treated overflows from the first tank 2 and flows into the second tank 3. The 2nd tank 3 is an intermediate cylinder provided with the wall part used as a higher position on the water surface than the 1st tank 2. As shown in FIG.
[0062]
The second tank 3 floats and separates the fine suspended matter adhering to the fine bubbles in the first tank 2, and settles and separates the relatively heavy particulate components in the upward flow that has risen up the first tank 2 on the upward flow. It has the function to do. The second tank 3 is provided with a suspended matter removing means 9 that adsorbs and removes floating substances that have been floated and separated, and a microorganism carrier 10 in the flow path of the second tank 3.
[0063]
The floating substance removing means 9 uses, for example, an adsorption filter or a separation membrane attached near the water surface of the second tank 3. The fine particles adhering to the fine bubbles in the for-treatment water pumped up in the first tank 2 float in the second-stage tank 3 from the for-treatment water whose flow velocity is slow, and are removed by the levitated substance removing means 9.
[0064]
The 2nd tank 3 is made into the conical intermediate cylinder which carries out diameter reduction according to the downward direction. As in this example, the second tank 3 may not be conical but may be a tubular cylindrical body. In addition, if the 2nd tank 3 is made into a cone-shaped intermediate cylinder body, a surface area will expand toward the upper part of the 2nd tank 3, the flow rate of the to-be-processed water which flowed in from the 1st tank 2 becomes slow, and it becomes a microbubble. Promotes floating separation of adhering fine particle components.
[0065]
As shown in the plan view of the first tank 2, the second tank 3, and the third tank 4 in FIG. 4, a plurality of microbial carriers 10 are provided in the second tank 3 in a radial manner. Since the to-be-processed water mixed with fine bubbles flows from the first tank 2 to the second tank 3, the dissolved oxygen in the second tank 3 increases, and the living environment for living organisms is favorable. For this reason, the microorganism carrier 10 provided in the second tank 3 is inhabited by a large number of microorganisms, and biologically decomposes the particulate components originating from the organic matter in the downward flow flowing slowly through the second tank 3.
[0066]
The flow rate of the downward flow flowing through the second tank 3 is set so as to be slower than the upward flow of the first tank 2, and the time required for biological decomposition treatment by microorganisms is ensured in the second tank 3. . For example, the flow rate of the downward flow of the second tank 3 can be set as appropriate by controlling the pumping amount of the pumping device 7 and adjusting the distance between the first tank 2 and the second tank 3. is there.
[0067]
Further, a reflux port 5 is provided between the first tank 2 and the second tank 3 as a reflux means for returning a part of the water to be treated flowing into the second tank 3 to the first tank 2 again. The residence time necessary for microbial treatment is adjusted
[0068]
Furthermore, by slowing down the flow velocity of the downward flow in the second tank 3, it is possible to promote sedimentation of large particles that do not adhere to the fine bubbles in the water to be treated.
[0069]
Since the second tank 3 is a conical middle cylinder whose diameter is reduced in the downward direction, the lower the surface of the second tank 3, the smaller the surface area. Since it becomes wider, the flow rate of the water to be treated flowing into the third tank 4 from the lower side of the second tank 3 becomes slow, and it flows slowly through the third tank 4 as an upward flow. Promotes settling.
[0070]
Between the 3rd tank 4 and the 1st tank 2, the closing plate 11 is provided centering on the 1st tank 2, and this closing plate 11 functions as a sediment accumulation means on which the big particle which settled from to-be-processed water accumulates. doing. The sediment deposited on the closing plate 11 is periodically removed by sediment removal means such as a suction pump 14. The closing plate 11 is provided with an accumulation portion 11a lower than other portions so as to be asymmetrical in the left-right direction. Since the sediment deposited on the closing plate 11 naturally gathers in the accumulation portion 11a that is lower than the other portion, the sediment collected in one place can be easily removed by the suction pump 14. In addition, as shown in the drawing, not only when the closing plate 11 is tilted asymmetrically to provide a single stacking portion 11a, but by changing the tilting direction of the closing plate 11, multiple stacking portions 11a are provided. Also good.
[0071]
When the fine bubble generator 6 for supplying fine bubbles to the first tank 2 is provided below the closing plate 11, the fine bubbles generated from the fine bubble generator 6 flow into the first tank 2 efficiently. The closing plate 11 may be installed in a tilted manner so that the part attached to the first tank 2 is at the upper position and the part attached to the third tank 4 is at the lower position.
[0072]
Since the third tank 4 is an outer cylindrical body having a wall portion that is at a lower position on the water surface than the second tank 3, the third tank 4 becomes a downward flow in the second tank 3 and flows into the third tank 4. The treated water collides with the wall of the third tank 4 and becomes an upward flow, overflows from the upper part of the third tank 4 and is discharged onto the water surface of the closed water area.
[0073]
Since the third tank 4 circulates the water to be treated as an upward flow, it settles and separates from the water to be treated, and the sediment deposited on the closing plate 11 is not rolled up and mixed into the water to be treated. Functions as a tank.
[0074]
In the water quality improvement system 1, the anoxic water and polluted water pumped up by the pumping device of the first tank 2 are treated with clarified water in the first tank 2, the second tank 3 and the third tank 4. Therefore, since the system is a complete system in the tank, the upper layer used as a tap water source can be expanded by purifying the oxygen-poor water and the polluted water area in the closed water area without disturbing the pollutants in the surface vicinity layer and the upper layer. Moreover, in a closed water area such as a relatively shallow lake that cannot be divided into upper, middle, and lower layers, the water quality of the entire closed water area can be improved.
[0075]
A float 12 is provided on the outer periphery of the first tank 2, the second tank 3, and the third tank 4, and a gantry 13 that connects the float 12 and each tank is provided. By providing the float 12, the water quality improvement system 1 can be levitated to an arbitrary position in the dam lake. For example, various water qualities at arbitrary positions in a closed water area are measured, and the water quality improvement system 1 is moved to a target position based on the measurement result, thereby improving the water quality of anoxic water and polluted water areas in a wide range of closed water areas. be able to.
[0076]
The first tank 2, the second tank 3 and the third tank 4 of the water quality improvement system 1 are not limited to the concentric triple tank structure, but an elliptical cylindrical body is eccentric as shown in FIG. It is good also as the provided triple tank structure, and as shown in FIG.5 (b), not only a cylindrical body but the 1st tank 2, the 2nd tank 3, and the 3rd tank 4 are the triple bodies of the end surface rectangular tubular body. It is good also as a tank structure, and as shown in FIG.5 (c), it is good also considering a tubular body of an end surface rectangular shape as a triple tank structure eccentrically.
[0077]
FIG. 6 shows another embodiment of the water quality improvement system 1, and an inner cylinder that is long in the vertical direction is provided so that the first tank 2 reaches the poor oxygen water and the polluted water area. The closing plate 11 provided between the third tank 4 and the first tank 2 is provided so as to incline as a whole, and sediment deposited on the closing plate 11 naturally gathers in the accumulation portion 11a lower than other parts. In this way, the sediment is easily removed by the suction pump 14.
[0078]
FIG. 7 is an explanatory diagram showing a schematic configuration of the water quality improvement system 1 according to another embodiment of the present invention. As shown in FIG. 7, the water quality improvement system 1 overflows the water to be treated pumped up in the first tank 2 provided with the pumping device 7 and the microbubble generator 6 that generates microbubbles from below into the flow tank 3a. Circulates in the circulation tank 3a. And the to-be-processed water flows in into the 2nd tank 3 as a natural downward flow through the distribution tank 3a, and flows out into the closed water area as an upward flow from the 3rd tank 4 connected to the 2nd tank 3. FIG.
[0079]
The reflux means 5 is provided between the first tank 2 and the second tank 3, and the levitated substance separating means 9 and the microorganism carrier 10 that are levitated and separated are provided in the second tank 3. In the third tank 4, sediment that has settled and separated from the water to be treated is deposited and deposited on the closing plate 11 and the closing plate 11 that are continuously provided from the second tank 3 and have a lower accumulation portion 11 a than other parts. In addition, a suction pump 14 is provided for sucking and removing the sediment collected in the accumulation portion 11a. The first tank 2, the second tank 3, and the third tank 4 are supported on the water surface by the float 12 and the gantry 13.
[0080]
As shown in FIG. 7, the water quality improvement system 1 does not have the first tank 2, the second tank 3, and the third tank 4 as a triple tank structure, but has a continuous structure from the first tank 2 to the third tank 4. The tank may be configured as a complete system.
[0081]
【The invention's effect】
Since the present invention has the above-described configuration, the following effects can be obtained.
In the invention described in claim 1, in the first tank, fine particles originated from inorganic substances and organic substances that cause pollution and float in the closed water area of the anoxic water and the polluted water area, and are treated in the second tank. The microparticles derived from inorganic substances in the water are physically separated by floating and settling, and the microparticle components derived from organic substances in the water to be treated are biologically decomposed by the microorganisms supported on the microorganism carrier, and the third tank To discharge clear water to the closed water area. Since the water quality improvement system performs a complete process in the system, it releases clear water with an increased amount of dissolved oxygen while maintaining the water quality of the upper layer without disturbing the upper surface layer and the upper layer. The water area of the upper water used can be expanded, and the water quality of the closed water area such as a dam lake or lake can be improved efficiently. Moreover, in a closed water area such as a relatively shallow lake that cannot be divided into an upper layer, a middle layer, and a lower layer, the water quality of the entire closed water region can be improved.
[0082]
In the invention according to claim 2, since a reflux means for refluxing from the lower side to the first tank again is provided between the first tank and the second tank, the residence time required for processing the microorganisms supported on the microorganism carrier Can be adjusted.
[0083]
In the invention described in claim 3, since the first tank, the second tank, and the third tank have a triple tank structure, as a water quality improvement system of the tank complete type, a compact design that does not take up space is adopted. It is possible to provide a water quality improvement system for a closed water area that can save energy with a small operating capacity.
[0084]
In the invention of claim 4, the sediment depositing means is a simple structure that closes the space between the first tank and the third tank, and the sediment separated in the second tank is the middle layer water or the lower layer. It can be separated from the water to be treated without being mixed in the water.
[0085]
In the invention according to claim 5, since the closing plate which is the sediment depositing means is inclined and the accumulation portion lower than other portions is provided, the sediment deposited on the closing plate naturally falls. The collected sediment can be easily removed by gathering in the accumulation section.
[0086]
In the invention according to claim 6, since the second tank is a conical middle cylinder whose diameter is reduced in the downward direction, the surface area of the upper part of the second tank is enlarged and flows into the second tank from the first tank. The flow rate of the water to be treated is slowed, the floating separation of fine particles adhering to the fine bubbles is promoted, the surface area of the lower part of the second tank is made narrower, the surface area of the lower part of the third tank is enlarged, and the second tank Thus, the flow rate of the water to be treated flowing into the third tank is slowed to promote the sedimentation / separation of large particles not adhering to the fine bubbles, and the physical treatment comprising the floating separation / sedimentation separation can be effectively performed.
[0087]
In the invention according to claim 7, since the first tank, the second tank and the third tank are configured to be continuous, and the treated water pumped up in the first tank is circulated by the head pressure, By utilizing the natural flow of water, it is possible to provide a water quality improvement system that realizes energy saving with low operating costs.
[0088]
In the invention according to claim 8, since the float that floats the first tank, the second tank, and the third tank on the water surface is provided, the water quality improvement system can be moved to an arbitrary position in the closed water area. Accordingly, it is possible to efficiently improve the water quality of anoxic water and polluted water areas in a wide range of closed water areas.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a schematic configuration of a water quality improvement system according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a state where FIG. 1 is installed in a closed water area.
FIG. 3 is a flowchart showing a purification method of the water quality improvement system.
4 is a plan view showing a first tank, a second tank, a third tank, and a microorganism carrier of the water quality improvement system shown in FIG. 1. FIG.
FIG. 5 is an explanatory diagram showing examples of the first tank, the second tank, and the third tank of the water quality improvement system.
FIG. 6 is an explanatory diagram showing a schematic configuration of another embodiment of the water quality improvement system of the present invention.
FIG. 7 is an explanatory diagram showing a schematic configuration of a water quality improvement system according to a second embodiment of the present invention.
[Explanation of symbols]
1; Water quality improvement system
2; First tank
3; Second tank
3a; Distribution tank
4; Third tank
5; refluxing means
6; Microbubble generator
7; Pumping equipment
9; Floating object removal means
10; microbial carrier
11; Closure plate
11a; Accumulation part
12; float
13; Mount
14; suction pump

Claims (8)

A water quality improvement system for closed water areas that improves the quality of anoxic water and polluted water areas in closed water areas, which pumps up the poor oxygen water and polluted water as an upward flow, and fine bubbles that generate fine bubbles from below. The first tank provided with the generating means and the water to be treated flowing out of the first tank are circulated as a descending flow having a flow rate slower than the flow rate of the upward flow of the first tank, A floater removing means having a function of separating sediment, a second tank provided with a microbial carrier in the flow path of the downflow, and a target to be discharged as a downflow from the lower side of the second tank From the third tank provided with sediment depositing means for draining water as an upward flow to the upper surface of the closed water area and depositing sediment settled and separated in the second tank and sediment removing means for removing the deposited sediment A water quality improvement system such as a closed water area. 2. The closed water area according to claim 1, wherein the first tank and the second tank are provided with reflux means for returning a part of the water to be treated flowing out from the first tank and flowing into the second tank from the lower side to the first tank again. Water quality improvement system. The first tank is an inner cylinder of a length that reaches the poor oxygen water and the polluted water area, the second tank is provided on the outer periphery of the first tank, and is higher on the water surface than the wall of the first tank. An outer cylindrical body provided with a wall portion that is provided on the outer periphery of the second tank, and has a lower wall position on the water surface than the wall portion of the second tank. The water quality improvement system for closed water areas according to claim 1 or 2. The water quality improvement system for a closed water area according to claim 3, wherein the sediment depositing means is a closing plate for closing a space between the lower part of the first tank and the lower part of the third tank. The water quality improvement system of the closed water area of Claim 4 which provided the accumulation | storage part which inclined the closing plate and was lower than another site | part. The water quality improvement system for a closed water area according to claim 3, 4 or 5, wherein the second tank is a conical middle cylindrical body whose diameter decreases in the downward direction. The second tank is a tank continuous from the first tank in which the treated water pumped in the first tank is circulated by water head pressure, and the third tank is a tank connected to the second tank. Water quality improvement system for closed water areas. The water quality improvement system of the closed water area of Claim 1, 2, 3, 4, 5, 6 or 7 which provided the float in the 1st tank, the 2nd tank, and the 3rd tank.

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