JP4142811B2 - Method and apparatus for purifying water containing microkistess plankton to prevent the growth of plankton - Google Patents

Description

[0001]
[Industrial application fields]
TECHNICAL FIELD The present invention relates to a method and apparatus for purifying water containing plankton, such as plankton of the genus Microcystis, and in particular, toxic microkistis that survives in water of lakes, reservoirs, rivers and the like. The present invention relates to a method and an apparatus for purifying water containing plankton belonging to the genus Microkistis by efficiently preventing the growth of genus plankton.
[0002]
[Prior art]
Planktons of the genus Microkistis that form blue sea bream are known to produce off-flavors such as the liver venom microcystin. However, abnormalities occur in rivers, lakes, reservoirs, etc. In order to purify these substances, chlorine disinfection treatment is unavoidable in tap water purification plants, and it is also a problem that leads to the generation of carcinogen trihalomethane.
[0003]
Therefore, in the conventional water purification process including plankton, for example, the water purification process including floating microorganisms in the water such as reservoirs, lakes, and rivers, that is, water including plankton, uses an ultraviolet lamp (main wavelength 253.7 nm) in the water. A method of installing and passing water in the vicinity of the lamp for irradiation treatment, a method of dissolving chemical substances such as ozone in water and acting on plankton for chemical treatment, or pressurized water from the nozzle under atmospheric pressure A method of destroying plankton by killing the plankton by a method such as jetting and physically treating it by a sudden pressure change, etc., killing the plankton and stopping the plankton growth is used.
[0004]
[Problems to be solved by the invention]
However, depending on the type and characteristics of plankton, any method may cause variations in the effect of killing and / or destroying plankton, that is, the algicidal effect or the growth preventing effect, and is not necessarily an efficient treatment. For example, the plankton belonging to the genus Microkistis (commonly known as Aoko), which is often found in reservoirs and lakes, floats and accumulates near the water surface warmed by sunlight, forming flocs. The action of ozone and ozone becomes insufficient, and the killing efficiency and destruction efficiency of plankton due to ultraviolet irradiation and ozone are reduced. In addition, plankton physical cell destruction due to sudden pressure changes due to pressurized injection and plankton death due to cell destruction also vary greatly depending on the type of plankton. is there.
[0005]
As described above, none of the conventional plankton killing techniques is an efficient plankton killing process corresponding to the type and characteristics of plankton, that is, an algaecidal process. In particular, in the case of plankton accumulated in the form of flocs, there is a problem in that the algaecidal efficiency is lowered, for example, the irradiation efficiency of ultraviolet rays and the action efficiency of ozone are poor and the physical destruction efficiency by the fountain is not sufficient.
An object of the present invention is to solve problems such as low proliferation prevention efficiency in the conventional process of preventing growth of sea cucumbers.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems in the growth prevention treatment of the sea lion such as planktonic genus Microkistis, the present invention provides a more efficient method of killing or preventing the growth of planktonic genus Microkistis and killing the plankton. It has been completed as a result of various studies to develop an algae or growth prevention treatment device.
The inventors of the present invention have a relatively high temperature in the surface water area where the microkistis plankton is generated, and the pH value is increased to 9 to 11. Carbon dioxide dissolved in water essential for algae growth, For example, it is a bicarbonate ion, and since it is a form in which algae other than the plankton belonging to the genus Microkistis cannot be used, it inhibits the growth of the algae and helps the breeding of the plankton of the genus Microkistis. In such a water area, the bottom water area has a low pH range of 4.5 to 7, and phosphate ions (PO3−), which are nutrient sources for microkistis plankton, are easily eluted. Microkistis plankton is considered to proliferate abnormally.
[0007]
The present invention aims to promote the generation of planktons other than the genus Microkistis by balancing the ecosystem of the entire plankton phase and, as a result, to suppress the generation of planktons of the genus Microkistis. .
That is , the present invention is formed by separating the water sampled in the water area between the surface water area and the bottom water area in the water area to be purified by the ion-permeable partition and having an anode on one side of the partition. Introducing into the anode chamber and a cathode chamber formed with a cathode on the other side of the partition wall, respectively electrolyzing, generating acidic electrolyzed water in the anode chamber and generating alkaline electrolyzed water in the cathode chamber, The acidic electrolyzed water generated in the anode chamber was added to the water of the high pH surface water area of the water area to be purified , neutralized to lower the pH value of the surface water area, and also generated in the cathode chamber The alkaline electrolyzed water is neutralized in addition to the low pH bottom water of the water to be purified, and the pH value of the bottom water is increased, thereby increasing the level of microkitis in the water to be purified. To reduce the concentration Located method for purifying water containing Mikurokisutesu genus plankton to prevent the growth of Mikurokisutesu genus plankton to symptoms, the invention also, wherein the ion permeability of the partition wall, on one side of the partition wall is provided on the other side of the anode chamber and the septum wall anode is provided, and the electrolytic cell comprising a cathode compartment the cathode is provided, connected to the anode chamber of the electrolytic tank, outlet Connected to the acidic electrolyzed water outflow pipe provided in the high pH surface water area of the water area to be purified and the cathode chamber of the electrolytic cell, and the discharge port is provided in the low pH bottom water area of the water area to be purified The alkaline electrolyzed water outflow pipe, and the water sampling pipe having a water sampling port formed at the end disposed in the water area between the surface water area and the bottom water area in the water area to be purified , are connected via a water supply pump and a branch pipe. The anode chamber and the electrolytic cell Located water purification device comprising Mikurokisutesu genus plankton to prevent the growth of Mikurokisutesu genus plankton, characterized in that it is connected to the cathode compartment, further provided an ion permeable partition wall, on one side of the partition wall is provided on the other side of the anode chamber and the septum wall anode is provided, and the electrolytic cell comprising a cathode compartment the cathode is provided, connected to the anode chamber of the electrolytic tank, outlet An acidic electrolyzed water outflow pipe provided in a high pH surface water area of the water area to be purified and connected to a cathode chamber of the electrolytic cell, and a discharge port is a low pH bottom layer of the water area to be purified provided water, and alkaline electrolyzed water outlet pipe provided with a cooling device, water sampling pipe Mizuguchi adopted in the end portion is formed is connected to the anode chamber and cathode chamber of the electrolytic cell through the water pump and the branch pipe It is characterized by There is a device for purifying water containing microkistess plankton, which prevents the growth of plankton of the genus Microkistus .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, “plankton-containing water” means water in a water area such as a lake, reservoir, river or the like, that is, water such as lake water, marsh water, storage water, or river water. Water of lakes, reservoirs, rivers, etc., or water of lakes, reservoirs, rivers, etc. whose surface layer water has a pH value of 9 or more, and which has conditions that are liable to generate plankton belonging to the genus Microkistis To do.
[0009]
Since plankton that grows in water with a pH value of around 7 or less consumes carbon dioxide dissolved in water, the dissolved carbon dioxide is ingested in the process of carbon dioxide assimilation of plankton, resulting in the pH of the water. The value rises and carbon dioxide dissolved in the process is bicarbonate ionized. Plankton belonging to the genus Microkistis reproduces by ingesting bicarbonate ions (HCO3−), and therefore, the surface water of the water area where microkistis breeds has a pH value of 8 or higher, and therefore has a pH value of 7 Plankton that grows by ingesting dissolved carbon dioxide in nearby water is defeated and disappears.
[0010]
In the present invention, plankton belonging to the genus Microkistis grows, and the surface layer water having a pH value of 8 or more is neutralized with low pH electrolyzed water, that is, acidic electrolyzed water, so that plankton belonging to the genus Microkistis grows. The pH value of the water is lowered to, for example, 7 or less, HCO3− is changed to dissolved carbon dioxide, plankton and algae that inhabit the water with a pH value near 7 are propagated, and the growth of plankton belonging to the genus Microkistis is suppressed. This purifies the water in which the microkistis are growing.
Further, in the present invention, phosphate ions are eluted at the bottom of a water area such as a lake, reservoir, river or the like, and become a nutrient source for algae. Therefore, phosphoric acid is added to the bottom of a water area such as a lake, reservoir, river, or the like. Increase the pH value by adding high pH electrolyzed water that contains a large amount of cations to fix the phosphate, suppress phosphate ion elution, prevent enrichment of nutrients, such as microkistis plankton and other algae Reduces breeding and purifies water.
[0011]
As described above, the present invention electrolyzes water containing a water-soluble electrolyte such as lake water, reservoir water, river water, and the like, and the anode chamber has a low pH electrolysis having a pH value of 4.5 to 5, for example. Water, that is, acidic electrolyzed water is manufactured, and high pH electrolyzed water having a pH value of 8 to 9, for example, alkaline electrolyzed water is manufactured in the cathode chamber. In addition to the surface water area with a high pH value where plankton of the genus Kistis grows, the pH value of the water in the surface water area is lowered to 7.2 or less, for example 4.5 to 7.2, and the high pH produced in the cathode chamber Add electrolyzed water, that is, alkaline electrolyzed water, to the lower water area below the surface water area, neutralize the low pH value where phosphate ions, etc. at the bottom of lakes, reservoirs or rivers are likely to elute, and neutralize the pH value. Provide a cation that fixes phosphoric acid at the same time, e.g. And, by suppressing the elution of phosphate, it cuts off the growth of plankton Microcystis sp, and performs water purification.
[0012]
In the present invention, the water to be electrolyzed is water in a water area that is neutralized to block the growth of plankton belonging to the genus Microkistis, and water in the corresponding water area, for example, water in a lake, reservoir, river, etc. When treated, it is the corresponding lake, reservoir or river water respectively.
Waters of water between the surface waters and the bottom layer water is less relatively turbidity compared to water of the surface layer water and low-water, convenient not good for electrolytic treatment.
However, the microelectrolysis water proof pipe connected to the anode chamber of the electrolytic cell and equipped with a heating device and the alkaline electrolysis water effluent tube connected to the cathode chamber of the electrolytic cell and equipped with a cooling device prevent the growth of microkistis plankton. In the water purification apparatus containing the plankton belonging to the genus Kistis, even the surface water area and the bottom water area can be water to be subjected to electrolytic treatment. However, surface water can be sampled and electrolyzed, and the acidic electrolyzed water can be returned to a region different from the water sampling region of the surface water region. In this case, it is preferable because the water in the surface water area can be replaced relatively quickly.
[0013]
In the present invention, the electrolytic treatment includes an anode electrode and a cathode electrode connected to a power source, and the anode side and the cathode side are ion-permeable so that the water on the anode side and the water on the cathode side are not easily mixed therebetween. It is preferable to partition with a partition wall such as a conductive diaphragm. As such a partition, an ion permeable cation exchange membrane and an anion exchange membrane can be used. In this case, when an anion exchange membrane is disposed on the anode side and a cation exchange membrane is disposed on the cathode side, electrolysis can be continuously performed by supplying water to be electrolyzed to the region between the two membranes.
[0014]
In the present invention, the electrolytic cell is partitioned by partition walls to form an anode chamber having an anode and a cathode chamber having a cathode, and the anode chamber supplies anolyte from the anode chamber to a water area such as a lake, a reservoir, or a river. The cathode chamber is provided with a pipeline for supplying catholyte from the cathode chamber to a water area such as a lake, a reservoir, or a river. Furthermore, in the present invention, the anode chamber and the cathode chamber are provided with introduction pipes for introducing water such as lake water, marsh water, reservoir water, or river water from a water area such as a lake, a reservoir, or a river.
[0015]
The present invention provides acidic electrolyzed water obtained by electrolysis on the anode side in the high pH region in a water region having a high pH region containing plankton and a low pH region containing phosphate ions formed below the high pH region. In addition, since alkaline electrolyzed water obtained by electrolysis on the cathode side is added to the low pH region, the growth of microkistis plankton in the water that propagates in the surface water region is suppressed, and it propagates in the surface water region. The plankton concentration to be reduced can be reduced, thereby purifying water.
[0016]
【Example】
Hereinafter, the present invention will be specifically described with reference to the accompanying drawings, but the present invention is not limited to the following description and examples.
FIG. 1 is a schematic system diagram mainly showing an electrolytic treatment apparatus in one embodiment of the liquid purification apparatus of the present invention.
[0017]
In the embodiment shown in FIG. 1, the electrolytic treatment apparatus 1 is an example installed in the vicinity of the reservoir 2, and is provided with a plastic electrolytic tank 3. A movable partition wall 4 is provided. The partition wall 4 divides the inside of the electrolytic cell into two chambers 5 and 6. One chamber 5 partitioned by the partition 3 is provided with an anode electrode 7 to form an anode chamber 5, and the other chamber 6 is provided with a cathode electrode 8 to form a cathode chamber 6. . The anode electrode 7 and the cathode electrode 8 are connected to a power source (not shown) through conductive lines 9 and 10.
[0018]
In this example, by passing a current between the anode 7 and the cathode 8 to electrolyze the water in the electrolytic cell 3, acidic electrolyzed water is formed in the anode chamber 5 and alkaline electrolyzed water is formed in the cathode chamber 6. The In this example, an acidic electrolyzed water outlet 11 is formed in the side wall portion in the anode chamber 5, and an alkaline electrolyzed water outlet 12 is formed in the side wall portion in the cathode chamber 6. An acidic electrolyzed water outlet pipe 13 is connected to the acidic electrolyzed water outlet 11, and an alkaline electrolyzed water outlet pipe 14 is connected to the alkaline electrolyzed water outlet 12. In the upper part of the electrolytic cell 3, a raw water supply pipe is provided so that water (raw water) collected in the reservoir 2 electrolytically treated in the electrolytic cell 3 can be supplied to both the anode chamber 5 and the cathode chamber 6 of the electrolytic cell 3. Fifteen raw water branch supply sections 16 are provided (supports and the like are not shown). A raw water sampling section 18 is formed at the water sampling side end of the raw water supply pipe 15 by being surrounded by a net 17 for removing foreign substances such as dust.
[0019]
In this example, the acidic electrolyzed water take-out pipe 13, the alkaline electrolyzed water take-out pipe 14 and the raw water supply pipe 15 are supported by a column 20 standing on the bottom wall portion 19 of the reservoir 2 so as to be movable in the vertical direction. Each can be moved by a driving device. A temperature sensor function for measuring the water temperature of the surface water area 21, a pH sensor function for measuring the pH of the water area and a pH adjustment state, or an ion aggregation state of the water area is provided at the upper part of the support column 20. An upper sensor 22 having a conductivity sensor function or two or more of these sensor functions is provided on the support column 20 so as to be movable in the vertical direction, and a temperature for measuring the water temperature of the bottom water area 23 is provided below the support column 20. A lower sensor 24 having a sensor function, a pH sensor function for measuring the pH of the water area or a pH adjustment state, a conductivity sensor function for monitoring the ion aggregation state of the water area, or two or more of these sensor functions, The support column 20 is provided so as to be movable in the vertical direction. The raw water sampling section 18 of the raw water supply pipe 15 has a temperature sensor function for measuring the water temperature of the middle water area 25, a pH sensor function for measuring the pH of the water area and the pH adjustment state, or ion aggregation of the water area. An intermediate sensor 26 having a conductivity sensor function for monitoring the situation or two or more of these sensor functions is provided to be movable together with the raw water sampling section 18. The vertical movement of the upper sensor 22, the lower sensor 24, and the intermediate sensor 26 can be performed by operating a driving device based on the measurement data of each sensor.
In this example, the acidic electrolyzed water discharge pipe 13 has a discharge port 27 for acidic electrolyzed water in the surface water area 21, and the alkaline electrolyzed water discharge pipe 14 has an alkaline electrolyzed water in the bottom water area 23. The discharge port 28 is opened.
[0020]
The water in lakes, reservoirs, and rivers has a high water temperature in the surface water area, and the water temperature in the bottom water area is lower than the water temperature in the surface water area.
In this example, for example, depending on where the sampling location of the raw water of the reservoir is decided, the water temperature of the surface water area 21 will be lowered, the water temperature will be reversed, and a large amount of alkaline electrolyzed water will be consumed. Therefore, a heating device 29 is provided in the acidic electrolyzed water discharge pipe 13 having a discharge port 27 opened in the surface water area, and a cooling device 30 is provided in the alkaline electrolyzed water discharge pipe 14 having a discharge port opened in the bottom water area. Is provided.
[0021]
Since this example is configured as described above, water in the middle water area 25 of the reservoir, that is, raw water, is sucked and collected from the water sampling section 18 of the raw water supply pipe 15 by driving a raw water supply pump (not shown). Then, it is supplied from the raw water supply branch 16 of the raw water supply pipe 15 into the anode chamber 5 and the cathode chamber 6 of the electrolytic cell 3.
An electric current is passed between the anode and the cathode to electrolyze the raw water supplied into the electrolytic cell 3 to form acidic electrolyzed water in the anode chamber 5 and alkaline electrolyzed water in the cathode chamber 6.
The acidic electrolyzed water obtained in the anode chamber 5 is taken out from the acidic electrolyzed water outlet 11 and supplied into the surface water area 21 from the acidic electrolyzed water discharge port 27 of the acidic electrolyzed water outlet pipe 13. On the other hand, the alkaline electrolyzed water obtained in the cathode chamber 6 is taken out from the alkaline electrolyzed water outlet 12 and supplied into the bottom water zone 23 from the alkaline electrolyzed water outlet 28 of the alkaline electrolyzed water outlet pipe 14.
[0022]
At the beginning of the electrolytic treatment of this example, the water in the surface water area 21 had a water temperature of 25 ° C., a pH value of 9, and the number of cells such as plankton belonging to the genus Microkistis was 2,020,000 cells / ml. On the other hand, the water in the bottom water zone 23 had a water temperature of 25 ° C., a pH value of 4.5, and the total phosphorus elution amount was 44 mg / ml. In this example, the acidic electrolyzed water obtained in the anode chamber 5 has a pH value of 5 and is supplied to the surface water area where the microkistis plankton to be neutralized is propagated. The alkaline electrolyzed water No. 6 had a pH of 8 and was supplied to the bottom water area from which the phosphate to be neutralized was eluted.
In this example, the pH value of the surface water area 21 is reduced to 6.5 due to this neutralization treatment, whereby the number of cells such as microkistis plankton in the surface water area 21 is 2 before the neutralization treatment. , 020,000 / ml, but decreased to 5,000 / ml after neutralization. On the other hand, this neutralization treatment increased the pH value of the bottom water zone 23 to 6.5, and the total phosphorus elution amount before the neutralization treatment was 44 mg / ml. The phosphorus elution amount was reduced to 19 mg / ml.
[0023]
In this example, since the water temperature of the surface water area 21 and the water temperature of the bottom water area 23 are both the same temperature as 25 ° C., the heating device and the cooling device are not used. In this example, from the relationship of heating on the one hand and cooling on the other hand, it is preferable to use a heat medium to form a heating / cooling cycle in order to effectively use energy.
By comparing the water temperature of the surface water area 21 measured by the temperature sensor of the upper sensor 22 with the water temperature of the bottom water area 23 measured by the temperature sensor of the lower sensor 24, the position of the raw water sampling section 18 of the raw water supply pipe 15 is The raw water sampling section 18 is positioned while monitoring the water temperature of the intermediate sensor 26 so as to be positioned between the water temperature of the surface water area 21 and the water temperature of the bottom water area 23.
In this example, the amount of phosphate ions eluted in the bottom water region 23 is measured with a conductivity sensor, and the supply amount of alkaline electrolyzed water supplied from the alkaline electrolyzed water supply pipe is adjusted.
In this example, the purification of water in the reservoir area was taken as an example, but instead of the water in the reservoir area, it was applied to the lake area, swamp area, or river area, and the water in each area was purified. It can be performed.
[0024]
【The invention's effect】
The present invention is obtained by electrolysis on the anode side in a water region having a high pH region containing microkistis plankton and a low pH region containing phosphate ions formed below the high pH region. The pH value is decreased by adding acidic electrolyzed water, and in the bottom layer water region of the low pH region, alkaline electrolyzed water obtained by electrolysis on the cathode side is added to increase the pH value. By suppressing ions, the growth of plankton of the genus Microkistis in the surface water area can be suppressed, and the concentration of plankton that propagates in the surface water area can be reduced, so that the water area of the reservoir, the water area of the lake It is possible to purify water in swamp water or river water.
The present invention, as compared with the conventional method, reservoirs, it is easy to balance the plankton phase entire ecosystem in the waters such as lakes or rivers, soundness of the entire ecosystem of plankton phase of the waters Thus, it is possible to suppress the generation of plankton belonging to the genus Microkistis, which is excellent in preserving the environment of the water area.
[Brief description of the drawings]
FIG. 1 is a schematic system diagram mainly showing an electrolytic treatment apparatus in one embodiment of a liquid purification apparatus of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electric field treatment apparatus 2 Reservoir 3 Plastic electrolytic cell 4 Partition 5 Anode chamber 6 Cathode chamber 7 Anode electrode 8 Cathode electrode 9, 10 Conductive wire 11 Acidic electrolyzed water outlet 12 Alkaline electrolyzed water outlet 13 Acidic electrolyzed water outlet 14 Alkaline electrolyzed water extraction pipe 15 Raw water supply pipe 16 Raw water branch supply pipe 17 Foreign matter removing net 18 Raw water sampling part 19 Bottom wall part 20 of reservoir 2 Strut 21 Surface water area 22 Upper sensor 23 Bottom water area 24 Lower sensor 25 Middle water area 26 Intermediate sensor 27 Acidic electrolyzed water outlet 28 Alkaline electrolyzed water outlet 29 Heating device 30 Cooling device

Claims (3)

The water collected in the water area between the surface water area and the bottom water area in the water area to be purified is divided by an ion-permeable partition wall, and an anode chamber formed with an anode on one side of the partition wall and the partition wall Introduced into a cathode chamber formed with a cathode on the other side, respectively electrolyzed to generate acidic electrolyzed water in the anode chamber and alkaline electrolyzed water in the cathode chamber, generated in the anode chamber The acidic electrolyzed water is neutralized by adding to the water of the surface water area having a high pH in the water area to be purified, and the pH value of the surface water area is lowered, and the alkaline electrolyzed water generated in the cathode chamber is purified. Lowering the plankton concentration of Microkitis genus in the water in the water to be purified by neutralizing in addition to the water in the low water bottom water of the water to be purified and increasing the pH value of the bottom water micro, characterized Method for purifying water containing Mikurokisutesu genus plankton to prevent the growth of plankton Sutesu genus. Ion permeability of the partition walls, provided on the side of one of the partition wall, an anode is provided on the other side of it has the anode chamber and the septum wall provided, and the electrolytic cell comprising a cathode compartment the cathode is provided An acidic electrolyzed water outflow pipe provided in the surface water area of the high pH of the water area that is connected to the anode chamber of the electrolytic cell and the discharge port is purified; and a discharge port connected to the cathode chamber of the electrolytic cell. The alkaline electrolyzed water outflow pipe provided in the bottom water area of the low pH of the water area to be purified, and a water sampling port is formed at the end disposed in the water area between the surface water area and the bottom water area in the water area to be purified the water sampling tube is, water containing Mikurokisutesu genus plankton to prevent the growth of plankton Mikurokisutesu genus, characterized in that connected to the anode chamber and cathode chamber of the electrolytic cell through the water pump and the branch pipe Purification equipment. Ion permeability of the partition walls, provided on the side of one of the partition wall, an anode is provided on the other side of it has the anode chamber and the septum wall provided, and the electrolytic cell comprising a cathode compartment the cathode is provided , Connected to the anode chamber of the electrolytic cell , provided in the high pH surface water region of the water region where the discharge port is purified, connected to the acidic electrolyzed water outflow pipe equipped with a heating device, and the cathode chamber of the electrolytic cell , An alkaline electrolyzed water outflow pipe having a discharge port provided in the bottom water area of the low pH of the water area to be purified and provided with a cooling device, and a water sampling pipe having a water sampling port formed at an end thereof are provided with a water pump and a branch pipe. A device for purifying water containing plankton belonging to the genus Microchistes, which is connected to the anode chamber and the cathode chamber of the electrolytic cell via the microkistes plankton.

Images