JPH11128945A - Water purification apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of pollutant removal capability regardless of the water quality and pollutant difference, prevent clogging of a filtration means, and form a flocculation membrane densely having fine pores by controlling the production amount of aluminum hydroxide in the optimum level. SOLUTION: Suspended matter is flocculated by a flocculating means 13 to enlarge the flocs of the suspended matter and make the flocs easy to be separated by filtration and a floc determination means 14 for determining the shapes and the state of the floc membrane formed in the upper layer part of a granular filter material 12a at the time of filtering the enlarged flocs (large pollutants) by a filtering means 12 is installed, so that an optimum floc membrane can be formed and a stable and high purification capability is obtained. In other words, electrolyzed substances optimum for flocculation and filtration can be formed in a controlled manner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purifying apparatus for removing and purifying suspended substances contained in water for business use or home use.

[0002]

2. Description of the Related Art As a conventional water purification apparatus of this type, as shown in FIG.
There is a method in which aluminum is eluted by electrolysis, the suspended substances are cross-linked to each other to increase the particle diameter, and then filtered using a filtering means and, at the same time, circulated and kept warm by a water temperature control means (for example, JP-A-8-117737). No.). In FIG. 1, reference numeral 1 denotes a circulation pump for circulating water in the water tank 2, and 3 denotes a circulation flow path. Reference numeral 4 denotes an aggregating means for electrolyzing aluminum and eluting aluminum ions to aggregate suspended substances contained in water. Reference numeral 5 denotes a filtering means for filtering water containing aggregated suspended matter. Reference numeral 6 denotes water temperature control means for controlling water temperature, and reference numeral 7 denotes pH control means for keeping the pH of water at 6 to 8. Further, reference numeral 8 denotes a sterilizing means for sterilizing bacteria contained in water.

In this configuration, when the circulation pump 1 is operated, the water in the bathtub 2 circulates in the circulation flow path 3. At this time, the aggregating means 4 is operated while adjusting the pH of the circulating water by the pH adjusting means 7 to electrolyze aluminum and elute aluminum ions. When the aluminum ions are eluted, suspended substances contained in the water are aggregated to form aggregated flocs. Further, the water containing the flocculated floc was configured to be filtered (clarified) by the filtration means 5, sterilized by the sterilization means 8, heated by the water temperature control means 6, and returned to the bathtub 1.

[0004] While maintaining the circulating temperature in the water temperature control means 6 in an appropriate range, the suspended substance contained in the water is aggregated by the aggregation means 4 and filtered by the filtration means 5 to filter (declare). ) Had to keep the performance.

[0005]

In the above-mentioned conventional water purifier, the suspended matter contained in the bath water is mainly condensed and filtered to thereby mainly remove dirt such as grime and metal soap having a relatively large particle diameter. In this case, even if the amount of aluminum ions to be dissolved by electrolysis was small, a flocculated floc having a relatively large particle diameter could be formed, and the floc could be separated by the filtration means. However, in the case of mainly contaminants having relatively small particle diameters such as microorganisms and colloids of 1 μm or less that propagate in water, the flocculated floc formed at the beginning is small, and the flocculated floc can be separated by filtration. The method requires a large amount of aluminum ions, and when many aluminum ions are dissolved, a large amount of aluminum hydroxide is generated, and the generated aluminum hydroxide sometimes causes clogging of the filtration means at an early stage. In other words, the required amount of aluminum ions varies depending on the quality of dirt contained in water, and it is difficult to optimally control the amount of aluminum dissolved.

[0006]

In order to solve the above-mentioned problems, the present invention provides a circulating circuit for circulating water in a water tank, a circulating means provided in the circulating circuit, and a circulating means for circulating water. An aggregating means for aggregating flocculent floc formed by agglomerating suspended substances contained therein by an electrolysis product, a filtering means for filtering the agglomerated floc formed by the aggregating means with a particulate filter material filled therein, and an agglomerated floc captured by the filtering means Is provided with an aggregation determining means for determining the state of formation of the aggregated film formed in step (1).

[0007] According to the above invention, suspended substances such as dirt and bacteria contained in water are aggregated by the electrolysis substance generated by the aggregation means to increase the size thereof, and are separated by filtration by the filtration means. As described above, when the suspended substance is separated by filtration by the filtration means, a layer is gradually formed in the upper part of the filtration means by the aggregated suspended substance, and an aggregated film having extremely dense pores is formed. It becomes like. At this time, since the state of formation of the aggregated film is monitored by the aggregation determining means, an optimal aggregated film can be formed. That is, it is possible to control the generation of the electrolysis substance optimal for the aggregation.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bath water purifying apparatus according to a first aspect of the present invention includes a circulation circuit for circulating water in a water tank, a circulation means provided in the circulation circuit, and a circulation means for circulating water. An aggregating means for aggregating a suspended substance contained in water with an electrolysis product to form an agglomerated floc, a filtering means for filtering the agglomerated floc formed by the aggregating means with a particulate filter material filled therein, and a filtering means The apparatus has an aggregation determining means for determining the state of formation of the aggregated film formed by the aggregated flocs.

[0009] Then, suspended substances such as dirt and bacteria contained in the water are electrically adsorbed by the electrolysis substance generated by the aggregation means to aggregate and become large, and are separated by filtration by the filtration means. Along with this, inside the filtration means, the suspended substances that have aggregated and become larger are gradually deposited in layers on the upper part of the filtration means, forming an aggregated film having dense pores,
While monitoring the state of formation of the aggregation film by the aggregation determination means,
Since the aggregating means is optimally controlled, the aggregating means automatically stops the aggregating means when an optimal agglomerated film is formed. By detecting the formation of an optimal coagulation membrane in this way, high filtration and separation performance can be achieved by the coagulation membrane, which has electrical adsorption power and dense pores, without aggregating and increasing the size of suspended substances. It is maintained and removes relatively small dirt such as bacteria (about 1 μm in size). In other words, by controlling the aggregating means while monitoring the state of formation of the agglomerated film by the agglutination determining means, it is possible to control the generation of the electrolyzed substance optimally according to the water quality, the turbidity and the like.

According to a second aspect of the present invention, in the water purifying apparatus, the coagulation judging means includes a pressure detecting section for detecting pressures on an inflow side and an outflow side of the filtering means, and a pressure detecting section for detecting pressure based on a signal detected by the pressure detecting section. A pressure calculating unit for calculating the difference, and if the pressure difference calculated by the pressure calculating unit increases by more than a first predetermined value (1P1), the aggregating means is stopped and a second predetermined value (△ P2, △ P1 <△) P2) It has a judging unit that stops the circulating means if it increases more than the above.

[0011] When the suspended substance contained in the water is electrically aggregated by the aggregating means and filtered and separated by the filtering means, the agglomerated suspended substance is deposited on the upper layer of the particulate filter medium inside the filtering means. When the water flow resistance rises and increases by ΔP1, the aggregating means is stopped. This increase in water flow resistance results from the deposition of electrolyzed and suspended materials. However, during the operation of the aggregating means, the increase in the water flow resistance is mostly due to the deposition of the electrolytic substance. In other words, the state of formation of the aggregated film can be indirectly known by monitoring the amount of increase in water flow resistance (the amount of increase in pressure), a signal can be obtained in a short time, and the state of formation of the aggregated film that changes every moment is simple. Can be monitored. Further, if the water flow resistance increases with the filtration operation and increases by ΔP2, the circulation means is stopped. That is, the safety of the purification device is improved by setting ΔP2 as the abnormality detection value.

According to a third aspect of the present invention, there is provided a water purification apparatus, wherein the coagulation judging means detects a flow rate of water passing through the filtering means, and the change in the filtration flow rate based on a signal detected by the flow detecting means. A flow rate calculation unit for calculating the amount, and a determination unit for stopping the aggregating unit when the flow rate change amount calculated by the flow rate calculation unit decreases by a predetermined value or more, and stopping the circulation unit when the circulating flow rate becomes a predetermined value or less. Have

[0013] When the suspended substance contained in the water is electrically aggregated by the aggregating means and filtered and separated by the filtering means, the agglomerated suspended substance is deposited on the upper layer of the particulate filter material inside the filtering means. As a result, the circulation flow rate decreases, and if the circulation flow rate decreases by ΔQ1, the aggregating means is stopped. This reduction in flow rate is due to the deposition of electrolyzed and suspended materials. However, most of the decrease in the flow rate during the operation of the aggregating means is caused by the deposition of the electrolyzed substance. Therefore, by monitoring the amount of decrease in the flow rate, the state of formation of the aggregated film can be indirectly known. In addition, the flow rate Q required to directly detect the filtration flow rate and secure purification performance
When the value becomes 2 or less, the circulation means is stopped. Therefore, the operation in a state where the purification performance cannot be ensured can be determined at an early stage, and for example, control can be performed so as to shift to the cleaning operation of the filtering means.

According to a fourth aspect of the present invention, there is provided a water purification apparatus, wherein a bypass pipe for bypassing the aggregating means and the filtering means to the agglutination determining means, a flow detecting section provided in the bypass pipe, and a signal detected by the flow detecting section. And a determination unit for stopping the aggregating means when the flow rate change amount calculated by the flow rate calculation unit increases by a predetermined value or more.

When the suspended substance contained in the water is electrically aggregated by the aggregating means and filtered and separated by the filtering means, the agglomerated suspended substance is deposited on the upper layer of the particulate filter material inside the filtering means. As a result, the flow resistance of the filtering means increases, and the flow rate of the bypass pipe provided in parallel with the filtering means increases. This increase in flow rate is due to the deposition of electrolysates and suspended matter, but most of it is due to the formation of electrolysates. Therefore, the state of formation of the aggregated film can be indirectly known by detecting the passing flow rate. Also, even if the filtration means is clogged by the suspended matter, the water flows through the bypass pipe to ensure the circulation flow rate, so that the suspended matter can be prevented from settling at the bottom of the water tank, and does not give a bad impression visually. .

A water purification apparatus according to a fifth aspect of the present invention has an electrolysis controller for controlling the amount of electrolyzed substance generated by the aggregating means based on the determination detection signal of the aggregating determining means.

Then, based on the judgment detection signal of the aggregating means, the amount of the electrolysis product generated by the aggregating means is linearly feedback-controlled. In other words, depending on the water quality, the aggregating action of the electrolyzed substance is slightly different, and even if it takes a long time to form an agglomerated film, it is possible to increase the electrolytic current of the aggregating means (the amount of the electrolyzed substance generated depends on Faraday's law. Based), and an aggregated film can be formed in a predetermined time. As a result, an aggregated film can be stably formed even with different water qualities.

The water purifying apparatus according to a sixth aspect of the present invention has a pH adjusting means for adjusting the pH of the water in the circulation circuit based on the judgment detection signal of the aggregation judging means.

Then, the state of formation of the coagulated film is detected by the coagulation judging means, and the hydrogen ion concentration (pH) of the water circulating in the water tank is automatically adjusted to a predetermined value by the pH adjusting means based on the judgment detection signal. When the pH is adjusted in this manner, the charge neutralizing power of the electrolysis substance generated by the aggregating means increases (the surface charge is maximum around pH 5 to 6), and therefore the colloidal particles (particle diameter included in water) Small, has a large surface area per unit volume, and a large amount of surface charge. Therefore, many opposite charges are required to lose the surface charge.) As a result, large aggregated flocs are easily formed, and an aggregated film is easily formed.
Therefore, high-performance filtration performance in a short time can be secured.

The water purifying apparatus according to claim 7 of the present invention has a flocculation aid adding means for mixing the flocculation aid on the upstream side of the flocculation means based on the detection signal of the flocculation determination means. Then, the formation state of the aggregated film is detected by the aggregation determining means, and based on the determination detection signal, when the aggregation aid is added by the aggregation aid adding means, the addition amount of the aggregation aid is automatically calculated and added. You. When the coagulation aid is added in this way, the coagulation floc is effectively formed by the cross-linking action of the coagulation aid (the effect of the coagulation aid adsorbing to both electrolysis substances and bridging both to increase the bonding force). Form. Therefore, a strong aggregated film can be effectively formed, and stable purification performance can be obtained.

[0021]

【Example】

(Embodiment 1) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a water purification apparatus according to a first embodiment of the present invention, FIG. 2 is a flowchart illustrating operations of an aggregation determining unit and an electrolysis control unit, and FIG. 3 is a diagram showing surface charges (zeta potential) of colloid particles and turbidity of a water tank. It is a graph showing. In FIG. 1, reference numeral 9 denotes a circulation pump which is a circulation means for circulating water in a bathtub 10, and reference numeral 11 denotes a circulation circuit. 12 is a circulation circuit 1
The filter means is provided with a granular filter medium 12a filled therein and a filter bed 12b for supporting the granular filter medium. Reference numeral 13 denotes an aggregating means, which includes a positive electrode 13a and a negative electrode 13b made of aluminum, a constant current power supply 13c for supplying a current between the electrodes, and an electrolysis control means 13d for controlling the constant current power supply. Reference numeral 14 denotes a coagulation determination unit, and a first pressure detection unit 14 that detects a pressure on the inflow side of the filtration unit 12.
a and a second pressure detector 14b for detecting the pressure on the outflow side
And the first pressure detection unit 14a and the second pressure detection unit 14
a pressure calculator 14c for calculating a pressure difference based on the signal of b,
A determination unit is provided for stopping the aggregating means 13 when a predetermined pressure difference is secured. Reference numeral 15 denotes a temperature control means for maintaining the water temperature in the bathtub 10 at a predetermined temperature, and a thermistor 15a
And a heater section 15b.

Next, the operation and action at the time of filtration will be described with reference to FIGS. When the circulation pump 9 is operated, the bathtub 1
The bath water in 0 is sucked from the bathtub 10 into the circulation pump 9 through the circulation circuit and sent to the filtration means 12. At this time, the water temperature is detected by the thermistor 15a, and when the temperature is lower than the set temperature, the water is heated by the heater unit 15b.

At the same time, in the filtering means 12, a current flows between an anode 13a having aluminum as a substrate and a cathode 13b having stainless steel as a substrate to which a voltage is applied by a constant current power supply 13c, and aluminum ions are emitted from the anode 13a. Elute. When the aluminum ions are eluted, a chemical reaction occurs with the bath water to form electrically positively charged aluminum hydroxide. The bath water contains suspended substances such as stains and bacteria that are electrically negatively charged, but aluminum hydroxide acts as a binding medium between the suspended substances, and is electrically absorbed to several μm. The suspended material is enlarged to flocculated flocs of several tens of μm. The formed flocculated floc is filtered and separated (clarified) by the particulate filter medium 15a filled in the filtering means 15 provided on the downstream side, and is returned to the bathtub 10 through the filter bed 12b.

At this time, inside the filtration means 12, the aggregated floc and the aluminum hydroxide which did not form the aggregated floc are gradually deposited in the upper layer of the particulate filter medium 15a, and the aggregated film having dense pores is deposited. (Cake layer). The thickness and the binding force of the aggregated film increase with time, and the water flow resistance of the filtration means 12 gradually increases. This state is always detected by the first pressure detection unit 14a and the second pressure detection unit 14b provided on the upstream side and the downstream side of the filtration unit 12, respectively, and a pressure detection signal is sent to the pressure calculation unit 14c. , The rate of pressure rise per unit time and the amount of pressure rise are calculated. At this time, when the obtained pressure rise rate is less than a predetermined value, the electrolysis control means 1
The electrolytic current value is increased by 3d, and if the pressure rise rate exceeds a predetermined value, the electrolytic current value is controlled to decrease. After the electrolytic current value is further increased, if there is no improvement in the pressure rise rate, the pH adjusting means operates to change the pH to a slightly acidic (5.5 to 6.9) side. When the calculated pressure increase amount, which is the next calculated value, is less than the predetermined value, the above-described sequence is repeated again. When the pressure increase amount reaches the first predetermined value (△ P1), the determination unit 14d is started. The aggregating means 13 stops and the anode 13
Dissolution of aluminum from a stops. Also,
During the filtration operation, the amount of pressure rise is the second predetermined value (△ P2)
Is reached, the circulation pump 9 is stopped.

As described above, according to the first embodiment, the following effects can be obtained. (1) By providing the aggregating determination means 13d, an agglomerated membrane having fine and stable pores is formed in the filtering means 12 irrespective of the water quality. Therefore, effective filtration performance can be ensured not only during the operation of the aggregating means 13 but also after the aggregating means 13 is stopped.

(2) Since the aggregating means 13 is of the electrolysis type, the aggregation can be performed electrically, and maintenance-free aggregation can be realized.

(3) The amount of aggregation can be easily controlled by controlling the amount of current flowing between the electrodes. (4) High coagulation efficiency can be ensured because aluminum is used for the positive electrode.

(5) Since the aggregating means 13 is integrally provided in the filtering means 12, the size of the apparatus can be reduced.

(6) If the rate of pressure rise is not improved by controlling the electrolysis controller 13d, the pH of the circulating water is changed to a slightly acidic side by the pH adjusting means 16, so that flocculated flocs are easily formed. It is possible to ensure the turbidity and facilitate the formation of an aggregated film.

(7) Since the aggregation determining means 15 is monitored based on the pressure difference between the inflow side and the outflow side of the filtration means, the formation state of the aggregation film can be monitored simply and linearly.

(Embodiment 2) FIG. 4 is a schematic structural view of a water purification apparatus according to Embodiment 2 of the present invention, FIG. 5 is a flowchart showing the operation of the coagulation determining means and the electrolysis controller, and FIG. It is an enlarged view of a flock. In FIG. 4, the means for adding a coagulation aid 17 includes a supply pipe 17a connected to the circulation circuit 11 and a coagulation aid tank 9 in which the coagulation aid is stored. Others are the same as the first embodiment, and a detailed description is omitted.

Next, the operation when the coagulation aid adding means operates during the operation of the coagulation means will be described. When the circulating pump 9 and the flocculating means 13 are operated, the flocculated floc and the aluminum hydroxide which has not formed the flocculated floc are gradually deposited on the upper layer of the particulate filter medium 15a inside the filtering means 12, and the fine pores are formed. Coagulated film (cake layer)
To form The thickness and the binding force of the aggregated film increase with time, and the water flow resistance of the filtration means 12 gradually increases. This state is constantly detected by the first pressure detecting unit 14a and the second pressure detecting unit 14b provided on the upstream side and the downstream side of the filtering unit 12, respectively.
, A pressure increase rate per unit time and a pressure increase amount are calculated. At this time, when the obtained pressure rise rate is less than the predetermined value, the electrolytic current value is increased by the electrolysis control means 13d, and when the pressure rise rate exceeds the predetermined value, the electrolytic current value is decreased. Have been. After the electrolytic current value is further increased, if the pressure rise rate does not improve, the coagulation aid adding means 17 operates, and the coagulation aid stored in the coagulation aid tank 17b is circulated through the supply pipe 17a. Filtering means 1 sent to circuit 11
Flow into 2. In this case, as shown in FIG. 6, the flocculating aid negatively charged is electrically adsorbed on the positively charged aluminum hydroxide as well as the suspended substances such as scales and bacteria, and the large flocculent floc. Is formed.
Further, when the pressure increase amount, which is the next calculated value, is less than the predetermined value, the above-described sequence is repeated again.
At 4d, the aggregation means 13 stops, and the dissolution of aluminum from the anode 13a stops. Other operations and functions are the same as those in the first embodiment, and a description thereof will be omitted.

As described above, according to the second embodiment, the following effects can be obtained. (1) When the pressure increase rate is not improved even by controlling the electrolysis controller 13d, the coagulation aid is added by the coagulation aid addition means 17 to facilitate formation of coagulated flocs and secure turbidity performance. In addition, it is possible to easily form an aggregated film.

(2) An agglomerated film can be formed stably in a short time because water is low in turbidity and a flocculant is added even if the amount of suspended substances contained is small. Therefore, the purification performance can be obtained stably without variation in water quality.

(Embodiment 3) FIG. 7 is a schematic configuration diagram of a water purification apparatus according to Embodiment 3 of the present invention, and FIG. 8 is a flowchart showing operations of the aggregation determining means and the electrolysis controller. In FIG. 7, reference numeral 18 denotes a coagulation determining means, which is a flow detecting unit 18a provided in the circulation circuit 11, a flow calculating unit 18b which calculates a flow change (decrease) amount based on a signal from the flow detecting unit 18a,
A determination unit 18c that stops the aggregating unit 13 when a predetermined flow rate reduction amount is secured is provided. Others are the same as the first embodiment, and a detailed description is omitted.

Next, the operation of the aggregation determining means 18 will be described. When the circulating pump 9 and the flocculating means 13 are operated, the flocculated floc and the aluminum hydroxide which has not formed the flocculated floc are gradually deposited on the upper layer of the particulate filter medium 15a inside the filtering means 12, and the fine pores are formed. To form a coagulated film (cake layer). The thickness and the binding force of the aggregated film increase with time, and the water flow resistance of the filtration means 12 gradually increases. In this case, the amount of water passing through the circulation circuit 11 gradually decreases. This state is constantly detected by the flow rate detector 18a provided in the circulation circuit 11, and a detection signal is sent to the flow rate calculator 18c, and the circulating flow rate decreasing rate and the circulating flow rate increasing quantity are calculated. At this time, when the obtained circulating flow rate increase rate is less than the predetermined value, the electrolysis current value is increased by the electrolysis control means 13d,
When the rate of pressure rise exceeds a predetermined value, the electrolytic current value is also controlled to decrease. If the filtration flow rate reaches a predetermined value (Q2) during the filtration operation, the circulation pump 9 is stopped. Other operations and functions are the same as those in the first or second embodiment, and a description thereof will be omitted.

As described above, according to the third embodiment, the following effects can be obtained. Since the agglutination judging means 18 is monitored by the flow rate passing through the filtration means, the state of formation of the agglomerated film can be monitored simply and linearly.

(Embodiment 4) FIG. 9 is a schematic configuration diagram of a water purification apparatus according to Embodiment 4 of the present invention, and FIG. 10 is a flowchart showing the operation of the aggregation determining means and the electrolysis controller. In FIG. 9, reference numeral 19 denotes a coagulation judging means, a bypass pipe 19a for bypassing the filtering means, a bypass flow detecting means 19b provided in the bypass pipe, and a change (increase) in the bypass flow rate based on a signal from the bypass flow detecting section 19b. And a determination unit 19d that stops the aggregating unit 13 when a predetermined flow rate increase is secured. Others are the same as the first embodiment, and a detailed description is omitted.

Next, the operation of the aggregation determining means 19 will be described. When the circulating pump 9 and the flocculating means 13 are operated, the flocculated floc and the aluminum hydroxide which has not formed the flocculated floc are gradually deposited on the upper layer of the particulate filter medium 15a inside the filtering means 12, and the fine pores are formed. To form a coagulated film (cake layer). The thickness and the binding force of the aggregated film increase with time, and the water flow resistance of the filtration means 12 gradually increases. In this case, the amount of water flowing into the bypass circuit 19a gradually increases. This state is constantly detected by the bypass flow detector 19b provided in the bypass circuit 19a, a detection signal is sent to the calculator 19d, and the bypass flow increase rate and the bypass flow increase are calculated. At this time, when the obtained bypass flow rate increase rate is less than the predetermined value, the electrolysis current value is increased by the electrolysis control means 13d, and when the pressure increase rate exceeds the predetermined value, the electrolysis current value decreases. Is controlled.

Other operations and functions are the same as those in the first or second embodiment, and the description is omitted.

As described above, according to the fourth embodiment, the following effects can be obtained. (1) The aggregation determining means 19 is replaced with a bypass pipe 19a of a filtering means.
Since the flow rate is monitored by the flow rate, the formation state of the aggregated film can be monitored simply and linearly.

(2) Because of the presence of the bypass pipe 19a, even if suspended substances suddenly flow into the filtering means 12 and cause clogging, most of the suspended substances flow through the bypass pipe 12a and the circulation flow rate decreases. Thereby, the suspended solid does not settle on the bottom of the aquarium and does not give a bad impression to the appearance.

[0043]

As described above, according to the first aspect of the present invention,
In the bath water purifying apparatus according to the above, the state of formation of the flocculated film is monitored by the flocculation judging means, and when the flocculated film optimal for filtration is formed, the flocculating means is stopped. For this reason, a coagulated membrane is stably secured irrespective of water quality and the like, and high filtration performance can be obtained even after the coagulation means is stopped. In addition, there is no wasteful generation of an electrolysis substance.

In the water purifying apparatus according to the second aspect, the state of formation of the coagulated membrane is determined based on the amount of change in the pressure difference (pressure loss) between the inflow side and the outflow side of the filtration means, and the first set value (△ P1 ), The aggregating means can be stopped and an optimal agglomerated film can be formed. The second set value (△ P
By providing 2), an abnormal time can be detected and the safety of the purification device can be ensured.

In the water purifying apparatus according to the third aspect, the state of formation of the coagulation film is determined based on the amount of change in the flow rate of water passing through the filtration means, and the coagulation means is stopped when the coagulation film becomes equal to or less than a set value (△ Q1). In this way, an optimum coagulated membrane can be formed, and by detecting the required filtration flow rate (Q2), it is possible to detect a state where purification performance cannot be ensured.

In the water purifying apparatus according to the fourth aspect, the state of formation of the coagulation film is determined based on the amount of change in the flow rate of the water passing through the bypass pipe, and when the water concentration exceeds a set value, the coagulation means is stopped. An agglomerated film can be formed. Further, since the amount of circulating water circulating in the water tank is maintained without being extremely reduced, sedimentation of suspended solids can be prevented, and the appearance does not give a bad impression.

In the water purifying apparatus according to the fifth aspect, feedback control is performed based on the judgment detection signal of the coagulation judging means so as to increase or decrease the electrolytic current so that the amount of electrolyzed substance generated by the coagulation means becomes constant. . Therefore, even if the aggregating action of the electrolysis substance is slightly different depending on the water quality, the time required for forming the agglomerated film does not change, and the agglomerated film can be formed within a predetermined time.

In the water purifying apparatus according to the sixth aspect, the pH of the water in the circulation circuit is automatically adjusted to a predetermined value (weakly acidic range) by the pH adjusting means based on the judgment detection signal of the coagulation judging means.
For this reason, the charge neutralizing power of the electrolysis substance generated by the aggregating means can be increased (the surface electrification is maximum around pH 5 to 6), and the surface charge of the colloid particles contained in water can be easily reduced. Therefore, it is easy to form a large flocculated floc by being cross-linked with dirt and bacteria, and it is easy to form a flocculated film. Therefore, high-performance filtration performance in a short time can be secured.

In the water purifying apparatus according to the present invention, a required amount of the coagulation aid is added to the filtration means by the coagulation aid addition means based on the judgment detection signal of the coagulation judgment means. The action (the effect that the coagulation aid adsorbs to both electrolysis substances and bridges both to increase the bonding force) can effectively form the coagulated floc. Therefore, a strong aggregated film can be effectively formed, and even when the amount of suspended substances is small, fine bacteria can be stably filtered in a short time.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a water purification device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing operations of a coagulation determining unit, an electrolysis control unit, and a pH adjusting unit of the water purification device.

FIG. 3 is a diagram showing the zeta surface charge (zeta potential) and turbidity removal performance of colloid particles of the water purification apparatus.

FIG. 4 is a schematic configuration diagram of a water purification device according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing the operation of the coagulation judging unit, the electrolysis control unit, and the coagulation aid adding unit of the water purification apparatus.

FIG. 6 is a principle diagram showing an aggregation action.

FIG. 7 is a schematic configuration diagram of a water purification device according to a third embodiment of the present invention.

FIG. 8 is a flowchart showing the operations of a coagulation determining unit, an electrolysis control unit, and a pH adjusting unit of the water purification device.

FIG. 9 is a schematic configuration diagram of a water purification device according to a fourth embodiment of the present invention.

FIG. 10 is a flowchart showing the operations of a coagulation determining unit, an electrolysis control unit, and a pH adjusting unit of the water purification device.

FIG. 11 is a schematic configuration diagram of a conventional water purification device.

[Explanation of symbols]

 Reference Signs List 9 circulation pump (circulation means) 10 bathtub 11 circulation circuit 12 filtration means 12a granular filter medium 13 coagulation means 13d electrolysis control unit 14 collection determination means 14a first pressure detection unit 14b second pressure detection unit 14c pressure calculation unit 14d determination unit 16 pH adjustment means 17 Coagulation aid addition means 18 Coagulation determination means 18a Flow rate detection part 18b Flow rate calculation part 18c Determination part 19 Coagulation determination means 19a Bypass pipe 19b Bypass flow rate detection part 19c Bypass flow rate calculation part 19d Determination part

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B01D 35/027 B01D 29/08 540A 35/02 J (72) Inventor Toshiaki Hirai 1006 Odakadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. In company

Claims (7)

[Claims] 1. A circulation circuit for circulating water in a water tank, a circulating means provided in the circulation circuit for circulating water, and a suspended substance contained in water provided in the circulation circuit being agglomerated by an electrolysis product. A flocculating means for forming flocculated flocs, a filtering means for filtering the flocculated flocks formed by the flocculating means with a particulate filter material filled therein, and a state of forming a flocculated film formed by the flocculated flocs captured by the filtering means. A water purification apparatus comprising: A pressure detecting section for detecting pressures on an inflow side and an outflow side of the filtering section; a pressure calculating section for calculating a pressure difference based on a signal detected by the pressure detecting section; When the pressure difference calculated by the pressure calculation unit increases by a first predetermined value (△ P1) or more, the aggregating unit is stopped, and when the pressure difference increases by a second predetermined value (△ P2, △ P1 <△ P2) or more, the circulating unit is activated. The water purification device according to claim 1, further comprising a determination unit that stops the operation. 3. A flocculation judging means, comprising: a flow rate detecting section for detecting a flow rate of water passing through the filtering means; and a flow rate calculating section for calculating a change amount of a circulating flow rate based on a signal detected by the flow rate detecting section. A determination unit that stops the aggregating unit when the flow rate change amount calculated by the flow rate calculation unit decreases by a predetermined value or more, and stops the circulation unit when the circulating flow rate becomes equal to or less than a predetermined value. Water purification device. 4. A flocculation judging means calculates a flow rate change amount based on a bypass pipe bypassing the flocculation means and the filtering means, a flow rate detection section provided in the bypass pipe, and a signal detected by the flow rate detection section. The water purification apparatus according to claim 1, further comprising: a flow rate calculation unit that performs the calculation, and a determination unit that stops the aggregating unit when the flow rate change amount calculated by the flow rate calculation unit increases by a predetermined value or more. 5. The water purification apparatus according to claim 1, further comprising an electrolysis controller for controlling the amount of electrolyzed substance generated by the aggregating means based on the determination detection signal of the aggregating determining means. 6. The water purifying apparatus according to claim 1, further comprising pH adjusting means for adjusting the pH of the water in the circulation circuit based on the judgment detection signal of the coagulation judging means. 7. The water purification apparatus according to claim 1, wherein a coagulation aid adding means for mixing the coagulation aid is provided upstream of the coagulation means based on the judgment detection signal of the coagulation judgment means.