JP6205301B2 - Water treatment method and water treatment equipment - Google Patents

Description

  The present invention relates to a water treatment method and a water treatment facility in which water to be treated is separated by a membrane unit having a separation membrane.

  Conventionally, in the above water treatment method, microorganisms adhere to the separation membrane along with the water treatment, and the clogging of the membrane occurs as the amount of attached microorganisms increases, that is, so-called biofouling may occur. Are known.

  Then, in order to estimate the amount of microorganisms adhering to the membrane, for example, a reagent that reacts with microorganisms to generate a substance for detection is added to the water to be treated, and the water to be treated containing the reagent is sent to the membrane unit. There is known a water treatment method including a step of producing a detection substance by reacting with a microorganism and measuring the amount of the detection substance in concentrated water or permeated water obtained by membrane separation of the water to be treated.

  As this type of water treatment method, for example, a reagent that emits fluorescence when it reacts with microorganisms is used, and the amount of the detection substance that emits fluorescence generated when the reagent reacts with microorganisms is reduced in concentrated water or permeated water. The thing including the process to measure is proposed (patent document 1).

  In such a water treatment method, the amount of microorganisms attached to the separation membrane can be estimated by the step of measuring the amount of the substance for detection in the concentrated water or the permeated water. That is, the amount of microorganisms attached to the separation membrane can be estimated by measuring the amount of the substance for detection using the intensity of fluorescence as an index.

JP 2005-533638 A

  However, in such a water treatment method, since only a small part of the reagent reacts with the microorganisms attached to the membrane when the water to be treated containing the reagent is simply membrane-separated, the detection substance generated from the reagent is removed. There is a problem that the intensity of fluorescence and the amount of microorganisms attached to the separation membrane do not necessarily correlate, and the amount of microorganisms cannot be estimated with sufficient reliability.

  The present invention provides a water treatment method capable of estimating the amount of microorganisms attached to a separation membrane with sufficient reliability in water treatment in which water to be treated is membrane-separated by a membrane unit having a separation membrane. This is the issue. It is another object of the present invention to provide a water treatment facility capable of estimating the amount of microorganisms attached to a separation membrane with sufficient reliability in water treatment in which water to be treated is separated by a membrane unit having a separation membrane.

In order to solve the above problems, a water treatment method according to the present invention is a water treatment method in which water to be treated is separated by a membrane unit having a separation membrane,
An estimation step for estimating the amount of microorganisms adhering to the separation membrane, the estimation step including a reagent for reacting with the microorganism a reagent that reacts with the microorganism to produce a detection substance; Water is sent to the membrane unit to separate it into concentrated water and permeated water, and all the concentrated water and permeated water are returned to the water to be treated before membrane separation, so that the reagent containing the reagent that has passed through the membrane unit is returned. A reagent reaction step for circulating the treated water; and a treated water measurement step for measuring the amount of the detection substance in the treated water before membrane separation after the reagent reaction step.

  According to the water treatment method having the above structure, in the reagent reaction step, the treated water containing the reagent that has passed through the membrane unit is returned to the treated water before membrane separation by returning concentrated water and permeated water. In order to circulate, the unreacted reagent contained in the concentrated water or permeated water can be reacted with the microorganism attached to the separation membrane. Thereby, the reagent once passed through the membrane unit without reacting with the microorganism attached to the separation membrane can be reacted with the microorganism in the membrane unit. Therefore, since the amount of the detection substance generated from the reagent is sufficient, the amount of microorganisms attached to the separation membrane can be estimated with sufficient reliability.

The water treatment method of the present invention is a water treatment method in which water to be treated is separated by a membrane unit having a reverse osmosis membrane,
Having an estimation step of estimating the amount of microorganisms attached to the reverse osmosis membrane,
In the estimation step, in order to cause a reagent that reacts with the microorganism to generate a detection substance to react with the microorganism, the water to be treated containing the reagent is sent to the membrane unit and separated into concentrated water and permeated water, A reagent reaction step for circulating the treated water containing the reagent through the membrane unit by returning all the concentrated water and permeated water to the treated water before membrane separation, and the concentrated water after the reagent reaction step And a treated water measuring step for measuring the amount of the detecting substance in the treated water before membrane separation after the concentrated water measuring step or reagent reaction step for measuring the amount of the detecting substance in .

  In the water treatment method of the present invention, it is preferable to circulate the water to be treated 2 to 30 times in the reagent reaction step.

  The water treatment method of the present invention preferably includes a sterilization step of sending treated water containing a sterilizing agent to the membrane unit in order to reduce microorganisms attached to the separation membrane after the estimation step.

The water treatment facility of the present invention is a water treatment facility that performs membrane separation of water to be treated by a membrane unit having a separation membrane,
In order to react a reagent that reacts with the microorganism to produce a substance for detection with the microorganism, the water to be treated containing the reagent is sent to the membrane unit to be separated into concentrated water and permeated water, and the target before membrane separation. By returning all the concentrated water and permeated water to the treated water, the treated water containing the reagent that has passed through the membrane unit is circulated.
A treated water measuring unit for measuring the amount of the substance to be detected in the treated water before membrane separation that has been circulated is provided.

The water treatment facility of the present invention is a water treatment facility that separates water to be treated by a membrane unit having a reverse osmosis membrane,
In order to react a reagent that reacts with the microorganism to produce a substance for detection with the microorganism, the water to be treated containing the reagent is sent to the membrane unit to be separated into concentrated water and permeated water, and the target before membrane separation. By returning all the concentrated water and permeated water to the treated water, the treated water containing the reagent that has passed through the membrane unit is circulated.
A concentrated water measuring unit that measures the amount of the substance to be detected in the concentrated water obtained by membrane separation of the circulated water to be treated, or a substance to measure the amount of the substance to be detected in the circulated water to be treated before membrane separation. A treated water measuring section is provided.

  INDUSTRIAL APPLICABILITY The water treatment method and the water treatment facility of the present invention have an effect that the amount of microorganisms adhering to the separation membrane can be estimated with sufficient reliability in the water treatment in which the water to be treated is membrane-separated by the membrane unit having the separation membrane.

Schematic showing the outline of the water treatment facility of 1st embodiment. Schematic showing the outline of the water treatment facility of 2nd embodiment. The graph showing ratio of R value / O value with respect to the frequency | count of circulation of to-be-processed water.

  Hereinafter, a first embodiment of a water treatment facility according to the present invention will be described in detail with reference to the drawings. Drawing 1 is a figure showing the outline of the water treatment equipment of a first embodiment.

The water treatment facility 1 of the first embodiment is a water treatment facility that separates water to be treated by a membrane unit 3 having a separation membrane,
In order to cause a reagent that reacts with the microorganism to generate a substance for detection to react with the microorganism, the water to be treated containing the reagent is sent to the membrane unit 3 and separated into concentrated water and permeated water. It is configured to circulate the water to be treated containing the reagent that has passed through the membrane unit 3 by returning the concentrated water and the permeated water to the water to be treated.
A treated water measuring unit 8 is provided that measures the amount of the substance to be detected in the circulated treated water before membrane separation.

As shown in FIG. 1, for example, the water treatment facility 1 of the first embodiment includes a water tank 2 to be treated and a membrane unit that has a separation membrane and separates the water to be treated into concentrated water and permeated water. 3 and a treated water supply pipe 4 for supplying treated water from the treated water tank 2 to the membrane unit 3. And the water treatment facility 1 of 1st embodiment sends the to-be-processed water stored in the to-be-processed water tank 2 to the membrane unit 3 via the to-be-processed water supply pipe 4, and is concentrated by the membrane unit 3 which has a separation membrane. It is comprised so that water and permeated water may be obtained.
Moreover, the water treatment facility 1 of the first embodiment includes a pump P that pressurizes the water to be treated and a plurality of valves that control the flow of water in the facility. The pump P and valves will be described later.

During normal operation, the water treatment facility 1 of the first embodiment performs a water treatment in which water to be treated that does not include a reagent or a detection reagent is subjected to membrane separation by a membrane unit so as to obtain concentrated water and purified permeated water. It is configured.
In the water treatment facility 1 of the first embodiment, microorganisms may adhere to the separation membrane of the membrane unit 3 along with the water treatment, and the separation membrane may be clogged (biofouling).

  The water to be treated before containing the reagent is not particularly limited. For example, waste water such as factory effluent and sewage treatment effluent discharged from an electronic component manufacturing factory, or seawater, industrial water, tap water, and well water. River water is adopted.

In the concentrated water, for example, moisture is evaporated, and the residue is discarded. Further, the concentrated water is discharged into, for example, sewage or a river. The concentrated water is used after being reprocessed, for example.
On the other hand, the permeated water is used in applications such as pure water, production water, drinking water, and industrial cleaning water.

And the water treatment facility 1 of the first embodiment is, for example, when the normal operation is stopped, when the normal operation is started, when the amount of water to be treated separated in the normal operation reaches a predetermined amount, When the time reaches the predetermined time, when the separation membrane is clogged by the microorganisms adhering to the separation membrane and the pressure loss of the membrane unit 3 exceeds the reference value, the conductivity of the permeated water generated in the normal operation is When the set value is exceeded, the water to be treated containing the reagent is sent to the membrane unit to perform membrane separation, and while obtaining concentrated water and permeated water, the microorganisms attached to the separation membrane react with the reagent to detect the substance. Is configured to generate.
Furthermore, the water treatment facility 1 of the first embodiment includes a return unit (described later) that returns concentrated water and permeated water to the water to be treated before membrane separation. It is comprised so that the to-be-processed water containing the said reagent which passed may be circulated.

In addition, the water treatment facility 1 of the first embodiment automatically sets a predetermined estimation process to be described later in order to estimate the amount of microorganisms adhering to the separation membrane by measuring the amount of the detection substance after stopping the normal operation. It may be configured to perform time.
In addition, the water treatment facility 1 of the first embodiment automatically performs an estimation process described later in order to estimate the amount of microorganisms adhering to the separation membrane by measuring the amount of the detection substance before starting normal operation. It may be configured to perform for a predetermined time. In the water treatment facility 1 of the first embodiment, before starting the normal operation, the water to be treated is normally circulated in order to obtain the desired water quality of the permeated water obtained by the normal operation. By performing the estimation process described later using such a circulation operation of the water to be treated, the operation before the normal operation can be made efficient.

  As shown in FIG. 1, the water treatment facility 1 of the first embodiment includes the water tank 2 to be treated, the membrane unit 3, and the water supply pipe 4 to be treated. Furthermore, the water treatment facility 1 of the first embodiment includes a concentrated water return pipe 5 that returns concentrated water concentrated by the separation membrane of the membrane unit 3 to the water tank 2 to be treated, and permeation that has passed through the separation membrane of the membrane unit 3. A return section is provided that includes a permeate return pipe 6 that returns water to the water tank 2 to be treated. Moreover, the water treatment facility 1 of the first embodiment includes a reagent addition unit 7 (reagent addition tank) that adds a reagent to the water to be treated which is subjected to membrane separation by the membrane unit 3.

  Then, the water treatment facility 1 of the first embodiment sends treated water from the treated water tank 2 to the membrane unit 3 via the treated water supply pipe 4 in order to cause the reagent to react with the microorganisms attached to the separation membrane. Meanwhile, the reagent is added from the reagent tank 7 to the water to be treated. In addition, the treated water containing the reagent is subjected to membrane separation in the membrane unit 3 to obtain concentrated water and permeated water, and the concentrated water is returned to the treated water tank 2 via the concentrated water return pipe 5. The permeated water is returned to the treated water tank 2 through the permeated water return pipe 6. And it is comprised so that the to-be-processed water containing the reagent which passed through the membrane unit 3 may be circulated by returning concentrated water and permeated water to the to-be-treated water tank 2.

  That is, the water treatment facility 1 of the first embodiment returns the concentrated water from the concentrated water return pipe 5 as the return portion to the treated water tank 2 when reacting the microorganisms attached to the separation membrane with the reagent, and The permeate is returned from the permeate return pipe 6 serving as a return unit to the water tank 2 to be treated, and the concentrated water and the permeate are mixed in the water tank 2 and mixed in the water tank 2. The water is sent to the treated water supply pipe 4.

  According to the water treatment facility 1 of the first embodiment, when the microorganisms adhering to the separation membrane react with the reagent, the membrane unit is returned by returning the concentrated water and the permeated water to the water to be treated before membrane separation. Since the to-be-treated water containing the reagent having passed through is circulated for a predetermined time, the unreacted reagent contained in the concentrated water or the permeated water can be sufficiently reacted with the microorganism attached to the separation membrane. Thereby, the reagent which passed through the membrane unit without reacting with the microorganism attached to the separation membrane can be reacted with the microorganism in the membrane unit. Therefore, the amount of the detection substance generated from the reagent is sufficient.

As shown in FIG. 1, the water tank 2 to be treated is formed so as to store the water to be treated, and the treated water supply pipe is used to supply the water to be treated to the membrane unit 3. 4 is configured to send to 4.
Further, as shown in FIG. 1, the water tank 2 to be treated is configured to be able to store the concentrated water that has passed through the concentrated water return pipe 5, and the permeated water that has passed through the permeate return pipe 6. Can be stored inside. That is, the water tank 2 to be treated is configured to mix the returned concentrated water and the returned permeated water.

The treated water supply pipe 4 is configured to supply treated water sent from the treated water tank 2 to the membrane unit 3.
For example, as shown in FIG. 1, a pump P for pressurizing the water to be treated is attached to the water to be treated supply pipe 4. By the pump P, pressurized water to be treated can be sent to the membrane unit 3.

  The membrane unit 3 has a separation membrane and is configured to membrane-treat the treated water sent from the treated water supply pipe 4 into concentrated water and permeated water.

Examples of the separation membrane of the membrane unit 3 include a reverse osmosis membrane (RO membrane), an ultrafiltration membrane (UF membrane), a microfiltration membrane (MF membrane), and the like.
As the membrane unit 3, a conventionally known general unit is employed.

  As described above, the return unit includes the concentrated water return pipe 5 and the permeate return pipe 6, returns the concentrated water and the permeate to the water to be treated before membrane separation, and supplies the water to be treated containing the reagent. It is configured to circulate.

The concentrated water return pipe 5 is configured to send the concentrated water obtained by the membrane unit 3 to the water tank 2 to be treated.
Further, as shown in FIG. 1, a concentrated water discharge pipe 11 for discharging the concentrated water to the outside of the facility is attached in the middle of the concentrated water return pipe 5. The concentrated water discharge pipe 11 is attached to the concentrated water return pipe 5 at one end side, and is configured to discharge the concentrated water outside the facility by sending the concentrated water passing through the concentrated water return pipe 5 to the other end side. Yes.
Further, as shown in FIG. 1, a concentrated water return valve A and a concentrated water discharge valve B are attached in the middle of the concentrated water return pipe 5 and the concentrated water discharge pipe 11, respectively.

The water treatment facility 1 returns the concentrated water by operating the two valves described above (ie, opening the valve A and closing the valve B) when reacting the microorganism attached to the separation membrane with the reagent. The concentrated water obtained in the membrane unit 3 is returned to the treated water tank 2 through the pipe 5.
The water treatment facility 1 operates the above-described two valves (that is, closes the valve A and closes the valve A when the microorganisms adhering to the separation membrane do not react with the reagent (for example, during normal operation)). (B is opened), the concentrated water obtained in the membrane unit 3 is discharged out of the facility through the concentrated water return pipe 5 and the concentrated water discharge pipe 11.

The permeated water return pipe 6 is configured to send the permeated water obtained in the membrane unit 3 to the water tank 2 to be treated.
Further, as shown in FIG. 1, a permeated water discharge pipe 12 for discharging the permeated water to the outside of the facility is attached in the middle of the permeated water return pipe 6. The permeate discharge pipe 12 is attached to the permeate return pipe 6 at one end side, and is configured to discharge the permeate out of the facility by sending the permeate passing through the permeate return pipe 6 to the other end side. Yes.
Further, a permeate return valve C and a permeate discharge valve D are attached to the permeate return pipe 6 and the permeate discharge pipe 12 as shown in FIG.

The water treatment facility 1 returns the permeated water by operating the above two valves (ie, closing the valve D and opening the valve C) when the microorganisms adhering to the separation membrane react with the reagent. The permeated water obtained in the membrane unit 3 is returned to the treated water tank 2 through the pipe 6.
The water treatment facility 1 operates the above two valves (that is, the valve C is closed and the valve is closed when the microorganisms adhering to the separation membrane do not react with the reagent (for example, during normal operation)). By opening D), the permeated water obtained in the membrane unit 3 is discharged out of the facility through the permeated water return pipe 6 and the permeated water discharge pipe 12.

The return unit is capable of reacting the reagent more sufficiently, and returns the treated water containing the reagent for 1.5 minutes or more by returning the concentrated water and the permeated water to the treated water before membrane separation. It is preferable to be configured to circulate once. Moreover, it is preferable that the said return part is comprised so that the to-be-processed water containing a reagent may be circulated once within 20 minutes at the point that a reagent can fully react and time can be saved.
The number of circulations is calculated from the amount of water that exists in the facility and circulates in the facility, and the flow rate (flow velocity) per unit time in the water in the facility.

  For example, as shown in FIG. 1, the reagent tank 7 is configured to add a reagent to the water to be treated in the water supply pipe 4 to be treated. The reagent tank 7 may be configured to send the reagent into the water tank 2 to be treated.

  The reagent is not particularly limited as long as it generates a detection substance by reacting with a microorganism that can grow in water.

Examples of the reagent include a fluorescent reagent that generates a detection substance that emits fluorescence by reacting with a microorganism.
Examples of the fluorescent reagent include resazurin, 4-methylumbelliferyl phosphate, and pyranine phosphate.

  As the reagent, the fluorescent reagent is preferable in that it generates a detection substance that emits fluorescence that is easy to detect.

  The fluorescent reagent can be contained in a predetermined concentration in the water to be treated before membrane separation in terms of the amount before the reaction with the microorganism. For example, resazurin as the fluorescent reagent is preferably contained in the water circulating in the facility in an amount of 5 to 50 ppb, more preferably 10 to 20 ppb in terms of the amount before the reaction with the microorganism.

The water treatment facility 1 of the first embodiment is preferably configured to circulate the water to be treated with the reagent added 2 to 30 times, and preferably configured to circulate 2 to 20 times. More preferred.
That is, the water treatment facility 1 of the first embodiment is a total amount with respect to the total amount of the water to be treated, the concentrated water and the permeated water before the membrane separation when the reagent is added to the water to be treated before the membrane separation. It is preferable to be configured to return 2 to 30 times the concentrated water and permeated water to the water to be treated.
In other words, the water treatment facility 1 of the first embodiment is configured to return 2 to 30 times the amount of concentrated water and permeate to the treated water with respect to the theoretical amount of water that circulates once in the facility. It is preferable that Note that the theoretical amount of water that circulates once in the facility is the amount of water that is membrane-separated when the reagent is added to the water to be treated before membrane separation.
In addition, it is preferable that the water treatment facility 1 of the first embodiment is configured to have a total circulation time of 3 to 60 minutes for circulating the water to be treated to which the reagent is added 2 to 30 times. More preferably, it is configured to be 5 to 30 minutes.

  The water treatment facility 1 of the first embodiment estimates the amount of microorganisms adhering to the separation membrane by measuring the amount of the substance for detection in the treated water before the membrane separation that has been circulated by the treated water measuring unit 8. Is configured to do.

  For example, as shown in FIG. 1, the water to be treated measuring unit 8 includes a pipe 8a for water to be treated for feeding the water to be treated before membrane separation to the water tank 2 to be treated, and a pipe 8a for measuring the water to be treated. And a to-be-treated water measuring device 8b for measuring the amount of the substance to be detected generated by the reaction of the reagent with the microorganism.

And the said to-be-processed water measurement part 8 takes out a part of to-be-processed water before membrane separation, and is comprised so that the quantity of the substance for a detection in to-be-processed water may be measured.
That is, the treated water measuring unit 8 causes the microorganisms and the reagent attached to the separation membrane to react with each other by circulating the treated water, and then sends the treated water to the treated water tank 2 through the treated water measurement pipe 8a. On the other hand, the amount of the substance for detection in the water to be treated before membrane separation is measured.

A treated water return valve E is attached in the middle of the treated water measurement pipe 8a.
When the water to be treated 8 circulates the water to be treated in order to cause the microorganisms and the reagent adhering to the separation membrane to react with each other, the operation of the valve E in the pipe 8a for water to be treated is performed. It is comprised so that the transfer of to-be-processed water may be stopped.
Alternatively, when the water to be treated is circulated in order to cause the microorganisms adhering to the separation membrane and the reagent to circulate, the water to be treated is treated by the operation of the valve E. You may be comprised so that it may send to the to-be-processed water tank 2 via the piping 8a for a measurement.
Further, the treated water measuring section 8 stops the circulation of treated water and reacts the microorganisms adhering to the separation membrane with the reagent, and then, by operating the valve E, the treated water is measured for treated water. While being sent to the water tank 2 through the pipe 8a, the amount of the substance for detection in the water to be treated before membrane separation is measured by the water meter 8b.

  The treated water measuring device 8b is configured to measure the amount of the substance to be detected in the treated water after being circulated and before membrane separation. Specifically, for example, as shown in FIG. 1, the treated water measuring device 8b takes out a part of treated water before membrane separation containing a substance for detection by a treated water measuring pipe 8a and performs treatment. It is configured to measure the amount of sensing substance in the water.

  As the to-be-treated water measuring device 8b, for example, when the above-described fluorescent reagent is used as a reagent, a fluorescent intensity measuring device that measures the fluorescent intensity is used. As the fluorescence intensity measuring instrument, for example, a commercially available general fluorometer is used.

  As shown in FIG. 1, the water treatment facility 1 preferably further includes a sterilizing agent addition unit 10 that adds a sterilizing agent that reduces microorganisms attached to the separation membrane to the water to be treated before membrane separation.

For example, as shown in FIG. 1, the sterilizing agent adding unit 10 stores therein a sterilizing agent-containing liquid containing a sterilizing agent, and sends the sterilizing agent-containing liquid to the water to be treated in the treated water supply pipe 4. An addition tank 10a is provided.
And when the quantity of the substance for detection measured by the to-be-processed water measuring device 8b exceeds the predetermined amount, the water treatment facility 1 supplies the sterilizing agent-containing liquid from the sterilizing agent addition tank 10a of the sterilizing agent addition unit 10. It is comprised so that it may send to the to-be-treated water in the to-be-treated water supply pipe 4.

In addition, the water treatment facility 1 is configured so that, for example, when the pressure loss value of the membrane unit 3 reaches 1.05-1.20 times the initial pressure loss value, the sterilizing agent addition tank 10a of the sterilizing agent adding unit 10 is used. The sterilizing agent-containing liquid may be sent to the treated water in the treated water supply pipe 4.
Or when the pressure loss value of the membrane unit 3 reaches 1.05-1.20 times the pressure loss value after the sterilization treatment with the sterilizing agent, for example, the water treatment facility 1 You may be comprised so that the disinfectant containing liquid may be sent to the to-be-processed water in the to-be-processed water supply pipe 4 from the tank 10a for disinfectant addition.

  On the other hand, the water treatment facility 1 is measured by the treated water measuring device 8b while sending a certain amount of the sterilizing agent-containing liquid from the sterilizing agent addition tank 10a to the treated water in the treated water supply pipe 4, for example. When the amount of the detection substance exceeds a predetermined amount, when the pressure loss value of the membrane unit 3 reaches 1.05-1.20 times the initial pressure loss value, or when the pressure loss value of the membrane unit 3 is sterilized When the pressure loss value after the sterilization treatment with the agent reaches 1.05 to 1.20 times, the amount of the sterilizing agent-containing liquid sent from the sterilizing agent addition tank 10a to the water to be treated is increased. May be.

  In addition, the said bactericidal agent addition part 10 may be comprised so that the bactericidal agent containing liquid may be sent to the to-be-processed water tank 2 from the tank 10a for bactericidal agent addition.

  Examples of the germicide include an oxidizing germicide or a non-oxidizing germicide.

  Examples of the oxidizing bactericides include peroxides, halogen oxoacid salts, bonded halogen compounds, and halogenated sulfamic acid compounds.

The peroxide is a compound having a peroxide structure (—O—O—), a percarboxylic acid structure (—C (═O) —O—O—), or a peroxide ion (O ₂ ²⁻ ). .

Examples of the halogen oxoacid salts include chlorine oxoacid salts and bromine oxoacid salts.
Examples of the oxo acid salt of chlorine include hypochlorite, chlorite, chlorate, and perchlorate. Examples of the bromine oxoacid salt include hypobromite, bromite, bromate, perbromate, and the like.
Examples of the hypochlorite include calcium hypochlorite (bleaching powder), sodium hypochlorite, potassium hypochlorite and the like.

Examples of the bonded halogen compound include chloramine-T (sodium salt of N-chloro-4-methylbenzenesulfonamide, chloramine-B (sodium salt of N-chloro-benzenesulfonamide, N-chloro-paranitrobenzenesulfonamide). Sodium salt, trichloromelanin sodium salt or potassium salt, monochloromelanin sodium salt or potassium salt, dichloromelanin sodium salt or potassium salt, trichloroisocyanuric acid, monochloroisocyanuric acid sodium salt or potassium salt, dichloroisocyanurate Sodium salt or potassium salt of acid, monochlorohydantoin or monobromohydantoin or its 5,5-alkyl derivative, 1,3-dichlorohydantoin or 1,3-dibromohydride Such Knights Inn or 1-bromo-3-chloro-hydantoin or a 5,5-alkyl derivatives.
Examples of the halogenated sulfamic acid compound include chlorinated sulfamic acids such as an alkali metal salt or alkaline earth metal salt of N-monochlorosulfuramic acid, an alkali metal salt or alkaline earth metal salt of N, N-dichlorosulfamic acid, and the like. Compounds. Further, examples thereof include brominated sulfamic acid compounds such as alkali metal salts or alkaline earth metal salts of N-monobromosulfamic acid and alkali metal salts or alkaline earth metal salts of N, N-dibromosulfamic acid.
The bonded halogen compound is not limited to those described above, and a general bonded halogen compound (stabilized halogen compound) can be employed.

  On the other hand, the non-oxidizing fungicide is not particularly limited, and examples thereof include 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT), 2-methyl-4-isothiazolin-3-one (MIT). ), 2,2-dibromo-3-nitrilopropionamide (DBNPA), 2-bromo-2-nitropropane-1,3-diol (bronopol) and the like.

  Examples of the bactericides include peroxides, halogen oxoacid salts, bonded halogen compounds, halogenated sulfamic acid compounds, 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT), and 2-methyl-4. -Selected from the group consisting of isothiazoline-3-one (MIT), 2,2-dibromo-3-nitrilopropionamide (DBNPA), and 2-bromo-2-nitropropane-1,3-diol (bronopol) At least one of them is preferred.

  Next, a second embodiment of the water treatment facility according to the present invention will be described in detail with reference to the drawings. Drawing 2 is a figure showing the outline of the water treatment equipment of a second embodiment.

The water treatment facility 1 ′ of the second embodiment is a water treatment facility that separates water to be treated by a membrane unit 3 ′ having a reverse osmosis membrane,
In order to cause a reagent that reacts with the microorganism to generate a substance for detection to react with the microorganism, the water to be treated containing the reagent is sent to the membrane unit 3 ′ and separated into concentrated water and permeated water before membrane separation. The treated water containing the reagent that has passed through the membrane unit 3 ′ is circulated by returning the concentrated water and the permeated water to the treated water.
A concentrated water measuring unit 9 that measures the concentrated water obtained by membrane separation of the circulated water to be treated, and a treated water measuring unit 8 that measures the amount of the substance to be detected in the circulated water to be treated before membrane separation. It is equipped with.

The water treatment facility 1 ′ of the second embodiment is such that a reverse osmosis membrane is employed as a separation membrane, and further includes a concentrated water measuring unit 9 so that the concentrated water measuring unit 9 measures a substance for detection in the concentrated water. Except the point comprised, it is comprised similarly to the water treatment facility of 1st embodiment.
Moreover, in water treatment equipment 1 'of 2nd embodiment, operation similar to operation performed by 1st embodiment is performed.
In addition, the reverse osmosis membrane in the water treatment facility 1 ′ of the second embodiment is a separation membrane that does not transmit any of the reagent and the detection substance. Specifically, if the reverse osmosis membrane in the water treatment facility 1 ′ of the second embodiment is a separation membrane that does not allow either the reagent or the detection substance to pass through, the membrane is commercially available as an ultrafiltration membrane. Is also included.

For example, as shown in FIG. 2, the concentrated water measuring unit 9 includes a concentrated water measuring device 9 a that measures the amount of the substance for detection in the concentrated water. The concentrated water measuring device 9a is configured to measure the amount of the detection substance in the concentrated water after the water to be treated is circulated.
That is, the concentrated water measuring unit 9 is configured to measure the amount of the detection substance in the concentrated water by the concentrated water measuring device 9a while flowing the concentrated water containing the detection substance into the concentrated water return pipe 5. ing.

  As said concentrated water measuring device 9a, the thing similar to the to-be-processed water measuring device 8b mentioned above is mentioned.

  Then, 1st embodiment of the water treatment method which concerns on this invention is described.

The water treatment method of the first embodiment is a water treatment method in which water to be treated is membrane-separated by a membrane unit having a separation membrane,
An estimation step for estimating the amount of microorganisms adhering to the separation membrane, the estimation step including a reagent for reacting with the microorganism a reagent that reacts with the microorganism to produce a detection substance; Processed to contain the reagent through the membrane unit by sending water to the membrane unit and separating it into concentrated water and permeated water, and returning the concentrated water and permeated water to the treated water before membrane separation A reagent reaction step for circulating water, and a water to be treated measurement step for measuring the amount of the detection substance in the water to be treated before membrane separation after the reagent reaction step are included.

  The water treatment method of the first embodiment can be implemented using, for example, the water treatment facility 1 shown in FIG.

  The water treatment method of the first embodiment is a purification step for obtaining at least purified permeated water by membrane-separating water to be treated that does not contain a reagent by a membrane unit, and estimating the amount of microorganisms attached to the separation membrane by the purification step The estimation step.

  In the purification step, the water to be treated which does not contain the reagent is subjected to a water treatment using a membrane unit to obtain a concentrated water and a purified permeated water.

  In the purification step, microorganisms adhere to the separation membrane of the membrane unit 3 with water treatment, and the separation membrane may be clogged (biofouling).

  In the water treatment method, when clogging of the separation membrane occurs due to the purification step, for example, the degree of clogging of the separation membrane is determined using the pressure loss of the membrane unit 3 as an index, and the degree of clogging of the separation membrane is determined. The estimation step is performed in order to estimate the amount of microorganisms attached to the separation membrane after becoming relatively large.

  In the estimation step, the above-described operations can be employed. That is, the estimation step can be performed by performing the reagent reaction step and the to-be-treated water measurement step by employing the above-described operation or the like.

  For example, in the reagent reaction step, a membrane that reacts with microorganisms to generate a detection substance reacts with microorganisms attached to the separation membrane from the treated water tank 2 via the treated water supply pipe 4. While supplying the water to be treated to the unit 3, the reagent is added from the reagent tank 7 to the water to be treated. In the reagent reaction step, the water to be treated containing the reagent is subjected to membrane separation by the membrane unit 3 to obtain concentrated water and permeated water, and the concentrated water is treated through the concentrated water return pipe 5. The water is returned to the water tank 2, and the permeated water is returned to the water tank 2 through the permeated water return pipe 6. Then, the treated water containing the reagent that has passed through the membrane unit 3 is circulated by returning the concentrated water and the permeated water to the treated water tank 2.

In the reagent reaction step, the water to be treated is preferably circulated 2 to 30 times, and more preferably 2 to 20 times.
That is, in the reagent reaction step, the total return amount of the concentrated water and the permeated water is 2 with respect to the total amount of the concentrated water, the permeated water, and the water to be treated before membrane separation at the start of the step. It is preferable to make it 30 times.
In other words, in the reagent reaction step, 2 to 30 times the amount of concentrated water and permeate are returned to the water to be treated with respect to the theoretical amount of water that is circulated once in the water treatment facility for performing the step. It is preferable to do. Note that the theoretical amount of water that circulates once in the facility is the amount of water that is membrane-separated when the reagent is added to the water to be treated before membrane separation.
By performing the reagent reaction step in this manner, there is an advantage that the microorganisms attached to the separation membrane and the reagent can be reacted more reliably.

In the reagent reaction step, it is preferable that the time for returning the concentrated water and the permeated water to the water to be treated before membrane separation is 1.5 minutes or more in that the reagent can be more sufficiently reacted. More preferably, it is 5 minutes or more. That is, it is preferable that the time per circulation is 1.5 minutes or more.
In the reagent reaction step, it is preferable that the time for returning the concentrated water and permeate to the water to be treated before membrane separation is 30 minutes or less in that the reagent can be sufficiently reacted and time can be saved. More preferably, it is less than or equal to minutes. That is, it is preferable that the time per circulation is 30 minutes or less.

In the treated water measurement step, for example, a part of the treated water sent from the treated water tank 2 before membrane separation is taken out, and the amount of the detection substance in the treated water generated by reacting with microorganisms is measured. To do.
That is, in the said to-be-processed water measurement process, before the membrane separation which flows in the to-be-processed water measurement piping 8a, for example, the to-be-processed water is sent to the to-be-treated water tank 2 by the to-be-processed water measurement piping 8a The amount of the detection substance in the water to be treated is measured.

In the water treatment method of the first embodiment, after the estimation step, it is preferable to perform a sterilization step of sending treated water containing a sterilizing agent to the membrane unit 3 in order to reduce microorganisms attached to the separation membrane.
By performing the sterilization step, there is an advantage that microorganisms attached to the separation membrane with water treatment can be reduced.

  According to the water treatment method of the first embodiment, as described above, the microorganisms attached to the separation membrane and the reagent are sufficiently reacted by circulating water for a predetermined time or circulating a predetermined amount of water. be able to. Thereby, it is possible to accurately grasp the amount of the bactericide necessary for removing the microorganisms from the separation membrane. Therefore, according to the water treatment method, the amount of the sterilizing agent used can be minimized, and deterioration of the separation membrane due to the sterilizing agent can be reliably prevented.

  In the water treatment method of the first embodiment, the purification step is usually performed again after the estimation step. In addition, when the said sterilization process is performed, the said purification | cleaning process is normally performed again after this sterilization process.

  Furthermore, a second embodiment of the water treatment method according to the present invention will be described.

The water treatment method of the second embodiment is a water treatment method in which water to be treated is separated by a membrane unit having a reverse osmosis membrane,
An estimation step for estimating the amount of microorganisms adhering to the reverse osmosis membrane, wherein the estimation step includes a reagent containing the reagent so as to react a reagent that reacts with the microorganism to generate a detection substance with the microorganism. The treated water is sent to the membrane unit to be separated into concentrated water and permeated water, and the concentrated water and permeated water are returned to the water to be treated before membrane separation, whereby the sample containing the reagent that has passed through the membrane unit. Reagent reaction step for circulating treated water, and the detection substance in the treated water before membrane separation after the reagent reaction step or the concentrated water measurement step for measuring the amount of the detection substance in the concentrated water after the reagent reaction step The to-be-processed water measurement process which measures the quantity of this is included.

  The water treatment method of the second embodiment can be carried out, for example, using the water treatment facility 1 'shown in FIG. Moreover, the water treatment method of 2nd embodiment can be performed similarly to the water treatment method of 1st embodiment except the said concentrated water measurement process.

In the water treatment method of the second embodiment, the water to be treated is preferably water to be treated that has been subjected to turbidity treatment.
The turbidity removal treatment is a coarser filtration treatment than membrane separation using a reverse osmosis membrane.
As the turbidity treatment, a microfiltration membrane (MF membrane) treatment, an ultrafiltration membrane (UF membrane) treatment, a sand filtration treatment, or the like is employed.

The concentrated water measurement step can be performed by employing, for example, the above-described operation.
Specifically, in the concentrated water measurement step, for example, a part of the concentrated water containing the detection substance is taken out from the concentrated water in the concentrated water return pipe 5, and the amount of the detection substance in the concentrated water is set to the concentrated water. It measures with the measuring device 9a.

The water treatment facility and the water treatment method of the above embodiment are as exemplified above, but the present invention is not limited to the above exemplified water treatment facility and water treatment method.
Moreover, the various aspects used in a general water treatment equipment and a water treatment method are employable in the range which does not impair the effect of this invention.

  EXAMPLES Next, although an Example is given and this invention is demonstrated in more detail, this invention is not limited to these.

  The water treatment method was implemented by performing the estimation process which estimates the quantity of the microorganisms adhering to a separation membrane using the water treatment equipment typically shown in FIG.

<Water treatment equipment>
・ Total amount of water circulating in the facility: 5,000L
・ Membrane unit: A membrane unit having a reverse osmosis membrane as a separation membrane

<Estimation process>
・ Water to be treated: Biologically treated water of waste water discharged from the electronic component manufacturing factory ・ Flow velocity (flow rate): Set to 25 m ³ / h ・ Reagent: Fluorescent reagent (Resazurin)
It becomes resorufin after reacting with microorganisms. It is added once to the water to be treated so that the concentration in the circulating water in the facility is 15 ppb. The number of circulation: 0 to 10 times (calculated from the amount of water and the flow rate in the facility)
・ Measurement of reagent amount and detection substance amount (O value and R value)
(O value)
Measured value of fluorescence signal intensity at a light wavelength (634 nm) specific to the reagent:
Used as an index of the amount of reagent before reacting with microorganisms (R value)
Measured value of fluorescence signal intensity at a wavelength (583 nm) peculiar to the detection substance generated from the reagent:
Used as an index of the amount of detection substance produced by reacting with microorganisms (ratio of R value / O value)
The ratio of the R value to the O value was used as an index of the amount of microorganisms attached to the separation membrane.

(O value and R value after circulating water to be treated containing reagent)
The O value and R value after the water to be treated containing the reagent was circulated 0 to 10 times were measured with the water to be treated measuring device (8b) in FIG.

(Reference measurement value 1)
The O value and the R value in the water to be treated to which no reagent was added were measured by the water to be treated measuring device (8b) in FIG.

(Reference measurement value 2)
The to-be-treated water to which the reagent was added was subjected to membrane separation, and the O value and R value in the concentrated water before being circulated were measured with the concentrated water measuring device (9a) in FIG.

"Test condition 1"
An estimation process was performed using a water treatment facility immediately after the membrane unit was washed with an aqueous sodium hypochlorite solution.

"Test condition 2"
After the membrane unit was washed as in test condition 1 above, water treatment was performed in normal operation, and an estimation process was performed using a water treatment facility in which microorganisms adhered to the separation membrane to some extent.

  Table 1 shows the results of performing the estimation process under the test conditions as described above and evaluating the amount of microorganisms attached to the separation membrane. Further, in Table 1, FIG. 3 shows a graph of the ratio of R value / O value with respect to the number of circulations of the water to be treated.

In Table 1 and FIG. 3, the amount of microorganisms adhering to the separation membrane can be estimated with sufficient reliability by circulating the water to be treated containing the reagent, as can be understood from the ratio of R value / O value, for example. .
As can be seen from the reference measurement value 1, the reason why the measured values of the O value and the R value become + even in the water to be treated that does not contain the reagent is that the light detected in the measurement of the O value and the R value is This is probably because some material that emits light having the same wavelength as that of the wavelength is originally contained in the water to be treated. By comparing the R value and R value / O value ratio after circulation with the R value and R value / O value ratio of the reference measurement value 1, respectively, the water to be treated is circulated for detection. It is understood that the amount of substance can be reliably measured.

1, 1 ': Water treatment equipment,
2: treated water tank, 3: membrane unit, 4: treated water supply pipe, 5: concentrated water return pipe, 6: permeate return pipe, 7: reagent tank,
8: To-be-treated water measuring part 8a: Pipe for to-be-treated water measurement, 8b: To-be-treated water measuring device,
9: Concentrated water measuring unit, 9a: Concentrated water measuring device,
10: Disinfectant addition part, 10a: Tank for disinfectant addition,
11: Pipe for concentrated water discharge, 12: Pipe for permeate discharge,
A: Concentrated water return valve, B: Concentrated water discharge valve, C: Permeated water return valve, D: Permeated water discharge valve, E: Untreated water return valve.

Claims (8)

A water treatment method for separating water to be treated by a membrane unit having a separation membrane,
Having an estimation step of estimating the amount of microorganisms attached to the separation membrane,
In the estimation step, in order to cause a reagent that reacts with the microorganism to generate a detection substance to react with the microorganism, the water to be treated containing the reagent is sent to the membrane unit and separated into concentrated water and permeated water, A reagent reaction step for circulating the treated water containing the reagent that has passed through the membrane unit by returning all the concentrated water and permeated water to the treated water before membrane separation, and membrane separation after the reagent reaction step A water treatment method comprising a treatment water measurement step of measuring the amount of the detection substance in the previous water to be treated. The water treatment method according to claim 1 , wherein in the reagent reaction step, water to be treated is circulated 2 to 30 times. 3. The water treatment method according to claim 1 , further comprising a sterilization step of sending treated water containing a sterilizing agent to the membrane unit to reduce microorganisms attached to the separation membrane after the estimation step. A water treatment method for separating water to be treated by a membrane unit having a reverse osmosis membrane,
Having an estimation step of estimating the amount of microorganisms attached to the reverse osmosis membrane,
In the estimation step, in order to cause a reagent that reacts with the microorganism to generate a detection substance to react with the microorganism, the water to be treated containing the reagent is sent to the membrane unit and separated into concentrated water and permeated water, A reagent reaction step for circulating the treated water containing the reagent through the membrane unit by returning all the concentrated water and permeated water to the treated water before membrane separation, and the concentrated water after the reagent reaction step Characterized in that it comprises a concentrated water measuring step for measuring the amount of the substance for detection in the step or a water measuring step for measuring the amount of the substance for detection in the water to be treated before membrane separation after the reagent reaction step. Water treatment method. The water treatment method according to claim 4 , wherein in the reagent reaction step, water to be treated is circulated 2 to 30 times. After said estimation step, in order to reduce the microorganisms attached to the reverse osmosis membrane, a treatment water containing fungicide with the sterilization process to be sent to the membrane unit, water treatment method according to claim 4 or 5. A water treatment facility for membrane separation of water to be treated by a membrane unit having a separation membrane,
In order to react a reagent that reacts with the microorganism to produce a substance for detection with the microorganism, the water to be treated containing the reagent is sent to the membrane unit to be separated into concentrated water and permeated water, and the target before membrane separation. By returning all the concentrated water and permeated water to the treated water, the treated water containing the reagent that has passed through the membrane unit is circulated.
A water treatment facility comprising a treated water measuring unit for measuring the amount of the substance to be detected in the circulated treated water before membrane separation. A water treatment facility that separates water to be treated by a membrane unit having a reverse osmosis membrane,
In order to react a reagent that reacts with the microorganism to produce a substance for detection with the microorganism, the water to be treated containing the reagent is sent to the membrane unit to be separated into concentrated water and permeated water, and the target before membrane separation. By returning all the concentrated water and permeated water to the treated water, the treated water containing the reagent that has passed through the membrane unit is circulated.
A concentrated water measuring unit that measures the amount of the substance to be detected in the concentrated water obtained by membrane separation of the circulated water to be treated, or a substance to measure the amount of the substance to be detected in the circulated water to be treated before membrane separation. A water treatment facility comprising a treated water measuring unit.

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