JP2019206000A - Separation membrane contaminated state analytic method, filtration object water quality evaluation method using the method, and filtration system for performing separation membrane contaminated state analytic method - Google Patents

Abstract

To provide a method for analyzing the state of contamination of a separation membrane that enables simple and rapid analysis without being affected by water to be filtered in water treatment.SOLUTION: A method for analyzing the state of contamination of a separation membrane comprises: a filtering step of providing a separation membrane 14 in a flow path 3 of filtration target water 1 in water treatment and filtering the filtration target water 1 through the separation membrane 14; a light irradiation step of irradiating the separation membrane 14 with excitation light from a spectrophotometer 20 used for fluorescence spectroscopy; a fluorescence spectroscopy step of causing the spectrophotometer 20 to receive fluorescence from the separation membrane 14 for spectroscopy; an FEEM creation step of creating a three-dimensional excitation fluorescence matrix spectrum (FEEM) on the basis of information about the wavelength of the excitation light and the wavelength of fluorescence used in spectroscopy; and an FEEM analysis step of analyzing the contamination state of the separation membrane 14 on the basis of the relationship between the integrated value of the fluorescence intensity and the total amount of filtered water in a predetermined region of the created FEEM. There are also provided a water quality evaluation method and filtration system for water to be filtered.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for analyzing the state of contamination of a separation membrane used for filtering water to be filtered in water treatment, a method for evaluating the quality of water to be filtered using the method, and a filtration system for performing a method for analyzing the state of contamination of a separation membrane. .

  Filtration treatment using a separation membrane is performed in water treatment in various fields.

  Modern membrane filtration in water treatment was first performed in the practical application of a reverse osmosis membrane (RO membrane) developed for the purpose of seawater desalination. Later, filtration using separation membranes was expanded to ultrapure water production facilities such as low-pressure RO membranes in the semiconductor manufacturing industry. Currently, the membrane separation activated sludge process (MBR) in sewage treatment and industrial wastewater treatment, waterworks business Separation membranes are introduced in the water purification treatment facility.

  In such a water treatment facility using a separation membrane, a phenomenon occurs in which the water permeability of the separation membrane deteriorates due to adhesion or precipitation of components contained in the feed water on the surface of the feed water side membrane or in the pores of the separation membrane. That is, membrane fouling becomes a problem.

  Various studies have been conducted on the elucidation of membrane fouling-causing substances and fouling mechanisms so far toward the development of methods for suppressing membrane fouling. As for the causative substance of membrane fouling, it has been clarified that the high-molecular polysaccharide-like substance which is a hydrophilic component in the feed water is an important contaminant around 2000-2010. As for the progress of membrane fouling, membrane fouling progresses in the following order: 1) initial adsorption and pore clogging of organic matter, 2) deposition of gel layer, 3) deposition of cake layer. It is clarified that it is selectively adsorbed by the membrane and hydrogen bond during the adsorption contamination period.

  As described above, methods for evaluating and predicting the progress of membrane fouling based on the causative substances of membrane fouling and the mechanism of membrane fouling progress have been proposed.

  For example, in Patent Document 1, the quality of the supplied water supplied to the separation membrane is measured with a fluorescence sensor, and simultaneously, the differential pressure of water before and after filtration by the separation membrane is measured, and separation is performed based on these measured data. Disclosed is a method for detecting signs of membrane fouling or estimating the factors of membrane fouling that has occurred.

  According to the method of Patent Document 1, it is possible to detect a sign of membrane fouling or to estimate the factor of membrane fouling that has occurred. Therefore, it is possible to take early measures according to the factor of membrane fouling. It becomes possible.

  In addition, as analysis methods for identifying membrane fouling substances, methods for extracting clogging components from drugs that have actually been clogged with chemicals and methods for directly measuring film surface deposits using the FTIR method have been proposed. .

JP, 2014-136210, A

  However, according to the method of Patent Document 1, the amount of the causative substance of the membrane fouling contained in the supply water supplied to the membrane is extremely small, and the membrane fouling can be performed even if the causative substance is not detected by the fluorescence sensor. Often progresses. In such a case, an erroneous factor of film fouling is estimated, and therefore, a countermeasure for eliminating the erroneous film fouling is selected.

  Moreover, according to the extraction of the clogging component (membrane fouling component) from the separation membrane that is actually clogged with chemicals, the extraction operation requires a certain amount of time and effort, such as adjustment of the extraction solvent and extraction that requires a predetermined time. The recovered components and the recovery rate vary depending on the properties of the extract. Further, according to the direct measurement of the film surface deposit using the FTIR method, the moisture content of the sample greatly affects the measurement. Therefore, the complete drying operation of the sample is indispensable for the measurement by the FTIR method. That is, according to the chemical extraction and the FTIR method, complicated work is required, and a certain time is required for the analysis operation including the pretreatment.

  The present invention has been made in view of the above problems, and an object thereof is to provide a separation membrane contamination state analysis method that enables simple and rapid analysis without being affected by water to be filtered in water treatment. There is to do.

  In order to achieve the above object, the invention according to claim 1 includes a filtration step in which a separation membrane is provided in a flow path of water to be filtered in water treatment, and the filtration target water is filtered by the separation membrane, and fluorescence spectroscopy. A light irradiation step of irradiating the separation film with excitation light from a spectrophotometer to be used; a fluorescence spectroscopy step of causing the spectrophotometer to receive and split the fluorescence from the separation film; and a wavelength of the excitation light FEEM creation step of creating a three-dimensional excitation fluorescence matrix spectrum (FEEM) on the basis of the information and the information about the wavelength of the separated fluorescence, the integrated value of the fluorescence intensity and the total filtered water amount in a predetermined region of the created FEEM And an FEEM analysis step for analyzing the contamination state of the separation membrane based on the relationship between

  According to a second aspect of the present invention, in the method for analyzing a contamination state of the separation membrane according to the first aspect, the FEEM preparation step includes an excitation wavelength Ex (Y axis), a fluorescence wavelength Em (X axis), and a fluorescence intensity (Z A three-dimensional spectrum represented by (axis) is a contour map created according to the fluorescence intensity.

  According to a third aspect of the present invention, in the method for analyzing a contamination state of the separation membrane according to the first or second aspect, the FEEM analysis step includes a fluorescence wavelength of 290 nm to 330 nm and an excitation wavelength of 220 nm to the FEEM to be created. A region AP1 partitioned into a range of 240 nm, a region P1 partitioned into a range of fluorescence wavelengths of 290 nm to 320 nm and an excitation wavelength of 265 nm to 295 nm, and a region P2 partitioned into a range of fluorescence wavelengths of 320 nm to 395 nm and excitation wavelengths of 245 nm to 295 nm Of these, the integrated value of the fluorescence intensity with respect to the total amount of filtered water in at least one region, and the region H1 divided into the range of the fluorescence wavelength of 395 nm to 480 nm and the excitation wavelength of 250 nm to 295 nm, the fluorescence wavelength of 395 nm to 520 nm, and the excitation wavelength of 300 nm to 375 nm Region H2 divided into ranges When the integral value of the fluorescence intensity with respect to the total amount of filtered water in at least one region is obtained, and the increase rate of the integral value of the regions H1 to H2 is larger than the increase rate of the integral values of the regions AP1 and P1 to P2. , Characterized in that it is determined to be at the end of membrane fouling.

  Invention of Claim 4 is the water quality evaluation method of the water for filtration in water treatment, Comprising: From the FEEM preparation process in the separation membrane contamination state analysis method as described in any one of Claims 1-3, this FEEM A calibration curve creating step for creating a calibration curve from the correlation between the integral value and a known membrane blockage index value in advance, and the calibration curve creating step used for the filtration target water with the unknown membrane blockage index value Membrane filtration is performed by the same method as the method for analyzing the state of contamination of the separation membrane, and an FEEM of the separation membrane subjected to the membrane filtration is created. The integral value of the obtained FEEM is applied to the created calibration curve to determine the membrane blockage index value. A membrane blockage index value determining step.

  The invention according to claim 5 is a membrane filtration system for performing a contamination state analysis method for a separation membrane that is provided in a flow path of water to be filtered in water treatment and introduces and filters the water to be filtered. A holder detachably attached to the surface to be filtered of the separation membrane, an excitation light irradiation unit that is provided on the holder and irradiates the separation membrane with excitation light, and is provided on the holder, and after the filtration Based on the excitation light wavelength information of the excitation light and the spectroscopic fluorescence wavelength information, the fluorescence spectroscopic unit that spectrally separates the fluorescence emitted from the separation film that has absorbed the excitation light with respect to the separation membrane A FEEM creation unit for creating a three-dimensional excitation fluorescence matrix spectrum (FEEM) represented by an excitation wavelength as a Y-axis, a fluorescence wavelength as an X-axis, and a fluorescence intensity as a Z-axis, and the fluorescence wavelength of the created FEEM Territory From the integration value change in fluorescence intensity, characterized by enabling grasp the contamination state of the separation membrane.

The invention according to claim 6 is a membrane filtration system for performing a contamination state analysis method of a separation membrane that is provided in a flow path of water to be filtered in water treatment and introduces and filters the water to be filtered. A holder detachably attached to the surface of the separation target water of the separation membrane, a near infrared light irradiator provided on the holder for irradiating the separation membrane with near infrared light, and the near infrared light An emission light spectroscopic unit that splits the light emitted from the absorbed separation membrane, a two-dimensional absorption spectrum creation unit that creates a two-dimensional absorption spectrum of absorbance-spectral wavelength based on the spectrally emitted light wavelength information; the a, by the two-dimensional absorption spectrum creating section, the the absorption spectrum a ₁ by the measurement after the filtration of the separation membrane, asking the absorption spectrum a ₀ by the measurement before filtration of the separation membrane, the absorption spectrum of the by difference By obtaining a spectrum derived from the captured material by filtration of the resulting membrane, characterized by enabling grasp the contamination state of the separation membrane.

Invention of Claim 7 is a membrane filtration system of Claim 5, Comprising: The near infrared light irradiation part which is provided in the said holder and irradiates the said separation membrane with near infrared light, The said near red A two-dimensional absorption-spectral wavelength two-dimensional absorption spectrum is created based on the emission light wavelength information obtained by receiving the light emitted from the separation membrane that has absorbed external light and separating the light. has an absorption spectrum creating unit, wherein the the two-dimensional absorption spectrum creation unit, an absorption spectrum a ₁ by measurement after filtration of the separation membrane, the absorption spectrum a ₀ by the measurement before filtration of the separation membrane, by differential By obtaining a spectrum derived from a substance captured by filtration of the separation membrane, the contamination state of the separation membrane can be grasped, and the analysis by the fluorescence spectroscopy is used to obtain a protein. Detecting the structure and detecting the sugar structure by near-infrared spectroscopy, which irradiates near-infrared light to the filtered separation membrane, and grasping the contamination state of the separation membrane using both spectroscopy methods It is characterized by doing.

  According to the present invention, since the separation membrane, not the filtration target water, is subjected to analysis by either or both of fluorescence spectroscopy and near infrared spectroscopy, substances present in the filtration target water supplied to the separation membrane The analysis of the contamination state of the separation membrane including the preparation is simplified and the analysis time is shortened without being affected by the concentration or the like.

It is a mimetic diagram showing membrane filtration system 10 concerning a 1st embodiment of the present invention. It is an enlarged view of the attachment site | part to the separation membrane of the holder which concerns on this Embodiment. It is a flowchart of the contamination state analysis method of the separation membrane by the fluorescence spectroscopy and near infrared spectroscopy which concern on this Embodiment. It is a figure explaining a three-dimensional excitation fluorescence matrix spectrum (FEEM). It is a figure which shows the change of the fluorescence intensity (integral value) with respect to the change of the total filtered water amount. It is a figure which shows the calibration curve created from the correlation of fluorescence intensity (calculated integral value) and FP value. (A) Schematic diagram showing the arrangement of the separation membrane in the membrane filtration system used in one variation of the separation membrane contamination state analysis method according to the present embodiment, and (B) in the membrane filtration system used in another variation It is a schematic diagram which shows arrangement | positioning of a separation membrane. It is a block diagram of the fluorescence spectrophotometer 60 which concerns on 2nd Embodiment of this invention. It is a figure explaining the contamination state analysis method of the separation membrane which concerns on 2nd Embodiment of this invention. It is a figure which shows FEEM which concerns on the Example of this invention.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
A membrane filtration system for performing a separation membrane contamination state analysis method and a separation membrane contamination state analysis method according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram showing a membrane filtration system 10 according to the present embodiment, FIG. 2 is an enlarged view of a site where a holder is attached to a separation membrane, and FIG. 3 is a diagram showing contamination of the separation membrane by fluorescence spectroscopy and near infrared spectroscopy. FIG. 4 is a diagram for explaining a three-dimensional excitation fluorescence matrix spectrum (FEEM), FIG. 5 is a diagram showing a change in fluorescence intensity (integrated value) with respect to the total amount of filtered water, and FIG. 6 is a fluorescence intensity (calculation). It is a figure which shows the calibration curve created from the correlation of the integrated value) and FP value.

  As shown in FIG. 1, the filtration system 10 according to the present embodiment includes an immersion tank 12 into which the filtration target water 1 flows and a separation membrane 14 immersed in the immersion tank 12. On the downstream side of the separation membrane 14, a liquid feed pump 16 for feeding the filtrate 2 filtered by the separation membrane 14 downstream is provided. By operating the liquid feed pump 16, an object to be filtered in the immersion tank 12. Water 1 is filtered by the separation membrane 14. Therefore, the flow path 3 of the filtration target water 1 is conceptually indicated by a broken line arrow shown in FIG.

  As the method of membrane filtration, either a casing type or an immersion type may be selected, but an immersion type membrane filtration method is preferable from the viewpoint of easy attachment of holders 22 and 42 to be described later to the separation membrane 14, In the present embodiment, an immersion type membrane filtration method is employed.

  As filtration object water 1, what kind of things, such as seawater, river water, rain water, well water, sewage, and industrial drainage, may be used. Accordingly, examples of water treatment include various treatments such as seawater desalination treatment, ultrapure water production treatment in the semiconductor manufacturing industry, water purification treatment in the waterworks business, sewage treatment, and industrial wastewater treatment.

  In the present embodiment, a case where river water is used as the filtration target water 1 in the water purification treatment in the waterworks business will be described as an example.

  As the separation membrane 14, any membrane such as a flat membrane, a hollow fiber membrane, and a tubular membrane may be used. The material of the separation membrane can be appropriately selected from materials that can be used for the filtration in accordance with the properties of the water 1 to be filtered. However, in the case of performing analysis by fluorescence spectroscopy, which will be described later, it is preferable to use a separation membrane made of a material whose spectrum does not overlap with the membrane fouling substance to be detected. Examples of the material for such a separation membrane include PVDF, PTFE, cellulose yarn, and PVC. In the present embodiment, PVDF is used as the material of the separation membrane 14.

  Further, the separation membrane 14 includes an external pressure type and an internal pressure type, and is not particularly limited, but an external pressure type is preferable from the viewpoint of ease of mounting of the holders 22 and 42 described later. In the present embodiment, an external pressure type hollow fiber membrane is used as the separation membrane 14.

  Further, the pore size of the separation membrane 14 is not particularly limited, and is selected from a reverse osmosis membrane (RO), a nanofiltration membrane (NF), an ultrafiltration membrane (UF), a microfiltration membrane (MF), etc. according to the application. be able to. In this Embodiment, it is preferable that the separation membrane 14 is selected from an ultrafiltration membrane (UF) and a microfiltration membrane (MF) from the objective of the process of water purification in a waterworks business.

  Further, the membrane filtration system 10 is also separated from the spectrofluorometer 20 having the holder 22 that is detachably attached to the filtration target water 1 side surface 14 a of the separation membrane 14 provided in the flow path 3 of the filtration target water 1. A near-infrared light spectrophotometer 40 having a holder 42 detachably attached to the filtration target water 1 side surface 14 a of the membrane 14.

  In addition to the holder 22, the spectrofluorometer 20 is interposed between the spectrofluorometer main body 30 and the holder 22 and the spectrofluorometer main body 30 to transmit excitation light from the spectrofluorometer main body 30. Fluorescence transmission means 28 (one light transmission means) and fluorescence transmission means 28 that transmits fluorescence emitted from the separation membrane 14 that has been exposed to excitation light and is interposed between the holder 22 and the spectrofluorometer main body 30. Other light transmission means). The excitation light transmission means 26 and the fluorescence transmission means 28 are covered with a protective tube 24 (see FIG. 2) that protects them.

  As shown in FIG. 2, the holder 22 includes a holder main body 22 a to which the separation light 14 side ends of the excitation light transmission means 26 and the fluorescence transmission means 28 are fixed, and the holder main body. One end protrudes from the portion 22a, and the other end has two holding protrusions 22b having a flange portion for holding the hollow fiber 14b constituting the separation membrane 14. In the engaged state of the pinching protrusion 22b and the hollow fiber 14b, light can be transmitted and received between the separation membrane 14 and the spectrofluorometer main body 30.

  The excitation light transmission means 26 and the fluorescence transmission means 28 are only required to be able to transmit excitation light and fluorescence, respectively. For example, an optical fiber is used.

  As shown in FIG. 1, the spectrofluorometer main body 30 receives a light irradiation unit 32 capable of sequentially irradiating excitation light with an excitation wavelength of 220 nm to 600 nm, and fluorescence emitted by a sample that has absorbed the excitation light, The receiver / spectrometer 34 divides into wavelengths of 220 nm to 650 nm. Further, the spectrofluorometer main body 30 includes an FEEM creation unit 36, and the FEEM creation unit 36, the light irradiation unit 32, and the reception / spectral unit 34 are controlled by a control unit 38.

  The control unit 38 is a computer that includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. The control unit 38 develops the program stored in the ROM on the RAM and causes the CPU to execute a corresponding process. Note that the program is not limited to being stored in the ROM, but may be stored in a non-volatile random access memory (NVRAM).

  The FEEM creation unit 36 is a program for creating an FEEM. When this program is expanded on the RAM, the FEEM creation unit 36 creates the FEEM based on the information on the excitation wavelength irradiated by the light irradiation unit 32 and the information on the fluorescence wavelength received and dispersed by the reception / spectral unit 34. To do. As shown in FIG. 4, the FEEM is a three-dimensional spectrum represented by contour lines according to the fluorescence intensity, with the excitation wavelength Ex as the Y axis, the fluorescence wavelength Em as the X axis, and the fluorescence intensity (fluorescence intensity) as the Z axis. It was created by rewriting the figure.

  Next, the near infrared spectrophotometer 40 will be described. In addition to the holder 42, the near-infrared light spectrophotometer 40 is interposed between the near-infrared light spectrophotometer main body 50 and the holder 42 and the near-infrared light spectrophotometer main body 50. The sample is interposed between the near-infrared light transmission means 44 (one light transmission means) for transmitting near-infrared light from the photometer main body 50 and the holder 42 and the near-infrared light spectrophotometer main body 50. Light transmission means 46 (other light transmission means) for transmitting light other than the light absorbed by the hollow fiber 14b of the separation membrane 14. The near-infrared light transmission means 44 and the light transmission means 46 are covered with a protective tube 48 (see FIG. 2) that protects them.

  As shown in FIG. 2, the holder 42 has a holder main body 42 a to which the separation film 14 side ends of the near-infrared light transmission means 44 and the light transmission means 46 are fixed in the attached state to the separation film 14, One end protrudes from the holder main body part 42a, and the other end has two holding protrusions 42b having a hook part for holding the hollow fiber 14b constituting the separation membrane 14. Light can be transmitted and received between the separation membrane 14 and the near-infrared light spectrophotometer main body 50 in the engaged state of the pinching protrusion 42b and the hollow fiber 14b.

  The near-infrared light transmission means 44 and the light transmission means 46 are only required to be able to transmit near-infrared light and its reflected light, and for example, an optical fiber is used.

  The near-infrared light spectrophotometer main body 50 is light emitted from a light irradiation unit 52 that can irradiate near-infrared light in a predetermined wavelength range and a sample (hollow fiber 14b of the separation membrane) that absorbs the near-infrared light. It has a reception / spectral unit 54 that receives (that is, light other than light absorbed by the sample) and separates it. Further, the near-infrared spectrophotometer main body 50 has an absorption spectrum creation unit 56, and the absorption spectrum creation unit 56, the light irradiation unit 52, and the reception / spectral unit 54 are controlled by the control unit 58.

  The control unit 58 is a computer including a CPU, a RAM, a ROM, etc., like the control unit 38 of the spectrofluorometer 30. The control unit 58 develops a program stored in the ROM on the RAM and performs a corresponding process. Is executed by the CPU. The program is not limited to being stored in the ROM, but may be stored in the NVRAM.

  The absorption spectrum creation unit 56 is a program for creating an absorption spectrum of near infrared light. When this program is expanded on the RAM, the absorption spectrum creation unit 56 creates an absorption spectrum based on the wavelength information received and spectrally received by the reception / spectral unit 54.

In the present embodiment, the absorption spectrum is a two-dimensional spectrum represented by the absorbance as the Y axis and the spectral wavelength as the X axis, and was measured after filtration of the separation membrane 14 immersed in the filtration target water 1 in the immersion tank 12. expressed as the difference in the absorption spectrum a ₁ and the absorption spectrum a ₀ measured prior to filtration dipping bath 12 separation membrane 14 is immersed in the filtered water being 1 in. That is, the difference absorption spectrum represents a spectrum derived from a substance trapped in the separation membrane 14 by filtration.

  The spectrofluorometer 20 and the near-infrared spectrophotometer 40 may always analyze the contamination state of the separation membrane 14, but may also be used when the membrane filtration system 10 is regularly checked.

  A method for analyzing the contamination state of the separation membrane 14 used for the filtration of the filtration target water 1 in the water treatment by the membrane filtration system 10 having the above configuration will be described below with reference to FIG.

  In the membrane filtration system 10, the holder 22 is already attached to the hollow fiber 14 b of the separation membrane 14, and similarly the holder 42 is attached to the hollow fiber 14 b of the separation membrane 14, and is based on fluorescence spectroscopy and near infrared spectroscopy. The separation membrane 14 can be analyzed. In this state, the membrane filtration system 10 is operated prior to the method for analyzing the contamination state of the separation membrane 14. That is, a predetermined amount of water 1 to be filtered (river water) is filtered by the separation membrane 14 by starting the liquid feed pump 16.

  Next, the liquid feed pump 16 is stopped, the filtration target water 1 in the immersion tank 12 is drained through a drainage path (not shown), and the separation membrane 14 is exposed from the filtration target water 1. In this state, as shown below, the contamination state of the separation membrane 14 after filtration is analyzed. In addition, by exposing the separation membrane 14 from the water 1 to be filtered, a separation membrane 14 (hollow fiber 14b) described later and each light transmission means (excitation light transmission means 26, fluorescence transmission means 28, The filtration target water 1 is interposed between the infrared light transmission means 44 and the light transmission means 46) on the separation membrane 14 side end, and the colloidal component and SS (suspended substance or suspended substance) contained in the filtration target water 1 ) Etc. are avoided. Therefore, the S / N ratio can be improved.

[Optical reception process (S101)]
First, the spectrofluorometer main body 30 and the near-infrared light spectrophotometer main body 50 are turned on, and both are activated.

  Thereby, in the spectrofluorometer main body 30, the control unit 38 sends a signal to the light irradiation unit 32 and the reception / spectral unit 34. With this signal, the light irradiation unit 32 sequentially irradiates the separation film 14 with excitation light having an excitation wavelength of 220 nm to 600 nm via the excitation light transmission means 26 (one light transmission means). Then, the fluorescence emitted from the separation membrane 14 that has absorbed the excitation light is transmitted to the spectrofluorometer main body 30 via the fluorescence transmission means 28 (other light transmission means). In addition, the reception / spectroscopy unit 34 receives the fluorescence transmitted to the spectrofluorophotometer main body 30 according to the signal from the control unit 38 and separates it into a fluorescence wavelength of 220 nm to 650 nm.

  At the same time, in the near-infrared light spectrophotometer main body 50, the control unit 58 sends a signal to the light irradiation unit 52 and the reception / spectral unit 54. With this signal, the light irradiation unit 52 irradiates the separation membrane 14 with near infrared light in a predetermined wavelength range via the near infrared light transmission means 44 (one light transmission means). Then, the reflected light / transmitted light other than the light absorbed by the separation membrane 14 (hollow fiber 14b) is transmitted to the near-infrared spectrophotometer main body 50 through the light transmission means 46 (other light transmission means). In addition, the reception / spectroscopy unit 54 receives the reflected / transmitted light transmitted to the near-infrared spectrophotometer main body 50 based on the signal from the control unit 58, and splits it into an arbitrary wavelength (the light receiving process is described above). S101).

[Spectral Spectrum Creation Step (S102)]
The spectral spectrum creating step S102 corresponds to the FEEM creating step in the fluorescence spectroscopy, and corresponds to the absorption spectrum creating step in the near infrared spectroscopy.

  In the fluorescence spectroscopy, the control unit 38 sends a signal to the FEEM creation unit 36. Thereby, the FEEM creation unit 36 performs the tertiary processing as shown in FIG. 4 based on the information on the wavelength of the excitation light irradiated by the light irradiation unit 32 and the information on the fluorescence wavelength received and dispersed by the reception / spectral unit 34. An original excitation fluorescence matrix spectrum (FEEM) is created.

  In the near infrared spectroscopy, the control unit 58 sends a signal to the absorption spectrum creation unit 56. Thereby, the absorption spectrum creating unit 56 creates an absorption spectrum based on the information about the wavelength received and split by the reception / spectral unit 54.

[Spectral spectrum analysis step (S103)]
The spectral spectrum analysis step S103 corresponds to the FEEM analysis step in the fluorescence spectroscopy, and corresponds to the absorption spectrum analysis step in the near infrared spectroscopy.

In the fluorescence spectroscopy, among the prepared FEEMs, the region AP1 is divided into a fluorescence wavelength range of 290 nm to 330 nm and an excitation wavelength range of 220 nm to 240 nm, and a fluorescence wavelength range of 290 nm to 320 nm and an excitation wavelength range of 265 nm to 295 nm. A region P1, a region P2 partitioned in a range of fluorescence wavelengths 320 nm to 395 nm and an excitation wavelength 245 nm to 295 nm, a region H1 partitioned in a range of fluorescence wavelengths 395 nm to 480 nm and an excitation wavelength 250 nm to 295 nm, and a fluorescence wavelength of 395 nm to 520 nm Using at least one region H2 divided into excitation wavelengths of 300 nm to 375 nm, the values (AP ⁱ , P1 ⁱ , P2 ⁱ , H1 ⁱ , H2 ⁱ ) obtained by integrating the fluorescence intensities in the region are obtained. . According to the preliminary test results, it has been found that substances having spectral peaks in the regions AP1, P1, P2, H1, and H2 increase with the progress of membrane fouling. By observing changes in the integrated values (AP ⁱ , P1 ⁱ , P2 ⁱ , H1 ⁱ , H2 ⁱ ) corresponding to the increase in the total amount of filtered water filtered, the contamination state of the separation membrane 14 can be grasped. .

  In the near-infrared spectroscopy, the peak area corresponding to the sugar structure part of the glycoprotein, which is a membrane-occluding substance, is calculated from the created absorption spectrum. The contamination state of the separation membrane 14 can be grasped by observing the change in the peak area corresponding to the increase in the total amount of filtered water filtered by the separation membrane 14.

  In addition, about spectral spectrum analysis process S103, you may perform by control of the control part 38 and the control part 58, and it is based on the absorption spectrum which the FEEM produced by the fluorescence spectrophotometer 20 and the near-infrared-light spectrophotometer 40 produced. Based on this, other methods may be used. Therefore, according to the membrane filtration system 10 for performing the contamination state analysis method for the separation membrane 14 and the contamination state analysis method for the separation membrane 14 according to the present embodiment, the separation membrane 14, not the filtration target water 1, is fluorescence spectroscopy. And the analysis using both near-infrared spectroscopy, it is possible to avoid problems such as analysis error and detection limit due to the influence of the substance existing in the filtration target water 1 and the concentration of the substance. Further, by analyzing the separation membrane 14, the influence of components that permeate the membrane on the analysis is eliminated, and only the membrane blocking component captured by the separation membrane 14 can be selectively analyzed.

  Furthermore, since the separation membrane 14 is analyzed by both fluorescence spectroscopy and near-infrared spectroscopy, the analysis operation including preparation is simplified, the time required is shortened, and simple and rapid analysis is possible. It becomes possible.

  In general, it has been clarified that the above-mentioned high-molecular-weight polysaccharide-like substances, which are substances that have an important influence on membrane fouling, are glycoproteins, but the protein structure can be detected by fluorescence spectroscopy. Yes, the sugar structure part could not be detected.

  According to the present embodiment, since it is possible to detect the protein structure part of the glycoprotein by fluorescence spectroscopy and to detect the sugar structure part of the glycoprotein by near infrared spectroscopy, it is the same level as the fluorescence spectroscopy. This makes it possible to more accurately analyze the membrane fouling-causing substance while maintaining the advantages of the simplicity and rapidity of the analysis.

  Further, the spectrophotometer main body (spectrofluorophotometer main body 30 and near-infrared light spectroscopy) is obtained by each light transmission means (excitation light transmission means 26, fluorescence transmission means 28, near-infrared light transmission means 44, and light transmission means 46). Light can be transmitted and received between the photometer main body 50) and the separation membrane 14 provided in the flow path 3 of the water 1 to be filtered. That is, since the in-situ (on-site) analysis of the separation membrane 14 is possible, it is not necessary to take out the separation membrane 14 from the immersion tank 12 and to attach the separation membrane 14 to the immersion tank 12 again after the analysis. Furthermore, the work related to the analysis of the contamination state of the separation membrane 14 is simplified.

  At the same time, the analysis is basically performed by irradiating the separation membrane 14 with light, and the separation membrane 14 is not excised, so that the separation membrane 14 after the analysis can be used continuously.

  In addition, according to the three-dimensional excitation fluorescence matrix spectrum (FEEM), the separation performance of the spectrum derived from each substance captured by the separation membrane 14 is improved as compared with the conventional one, and the overlap between the spectra is eliminated. It becomes possible to extract the spectrum of the substance to be accurately extracted.

  Moreover, it is possible to selectively monitor substances having spectral peaks in the regions AP1, P1, P2, H1, and H2 related to membrane fouling, and eliminate unnecessary spectra other than the target substance. be able to. Therefore, the S / N ratio can be improved.

  In the regions AP1, P1, and P2, there are peaks of the spectrum of glycoprotein that is a causative agent of sugar fouling, and in regions H1 and H2, the spectrum of the humic substance that is a substance involved in sugar fouling is present. The knowledge that a peak exists is obtained. In addition, AP1 is an area | region where the peak of the spectrum of the glycoprotein which has an aromatic functional group among the said glycoprotein exists.

In addition, as shown in FIG. 5, the inventor newly increased the fluorescence intensity of the regions AP1, P1, and P2 gradually from the beginning to the end of the progress of membrane fouling (see P in the figure). It was found that the fluorescence intensities of H1 and H2 were greatly increased at the end of the membrane fouling progression (see H in the figure) (in the figure, the vertical axis represents FEEM). The integrated value of the fluorescence intensity in the predetermined region (for example, P1 ⁱ ) is shown, and the horizontal axis shows the total amount of filtered water.)

  Therefore, in the FEEM analysis step (spectral spectrum analysis step S103) in the above embodiment, at least one of the regions AP1, P1 and P2 and the region H1 and the region among the FEEMs created in the FEEM creation step. At least one region of H2 may be used.

  According to this, by monitoring the change with respect to the total filtered water amount of each integral value of at least one of the regions AP1, P1 and P2, and at least one of the regions H1 and H2, FIG. As shown in FIG. 4, when the increase rate of the integrated values of the regions AP1, P1 and P2 is larger than the increase rate of the integrated values of the regions H1 to H2, the progress of the film fouling is in the initial to middle stage, When the increase rate of the regions H1 to H2 is larger than the increase rate of the integrated values of AP1 and P1 to P2, it can be determined that the film fouling is in the final stage. That is, the progress of membrane fouling and the end of membrane fouling can be grasped more accurately, and appropriate treatment can be performed on the separation membrane 14 before the separation membrane 14 is completely blocked.

  Note that the difference in the fluorescence intensity increase phenomenon between the regions AP1, P1 and P2 and the regions H1 and H2 as shown in FIG. 5 is that glycoproteins having spectral peaks in the regions AP1, P1 and P2 are directly attached to the membrane. This is due to the phenomenon that humic substances that cause membrane fouling and have a spectrum peak in the regions H1 to H2 adhere to the membrane occluding material attached to the separation membrane and promote membrane fouling rather than the separation membrane. It is inferred that

  In the FEEM analysis step, which is the spectral spectrum analysis step S103 of the above embodiment, it is also possible to use data obtained by converting the FEEM by the principal component analysis method. According to such conversion data, it is possible to efficiently extract, for example, a portion that contributes to film fouling among the peaks and valleys in the contour map represented by FEEM.

  Furthermore, the present invention provides a method for evaluating the quality of water to be filtered using FEEM produced in the method for analyzing the contamination state of a separation membrane. Below, the case of using the membrane filtration system 10 which concerns on the said embodiment is demonstrated with reference to FIG. 6 about the water quality evaluation method of the filtration object water which concerns on this Embodiment.

[Calibration curve creation step (S201)]
First, at least three types of filtration target waters with known membrane blockage index values are prepared. As such filtration target water, river water collected from a plurality of rivers can be used. Preferably, the filtration target water that is predicted to be close to the filtration target water that is the measurement target whose membrane occlusion index value is unknown should be selected.

  Any membrane occlusion index value may be used, and examples thereof include fouling potential (registered trademark) (FP), MFI, UMFI, MFI-NF, and CF-MFI. In the present embodiment, FP is used as a membrane blockage index. FP is a document written by the inventor of the present invention entitled “Proposal of Fouling Potential (Registered Trademark) in Water Treatment and Application of Submerged Membrane Filtration System” (Membrane, 39 (4), 194-200 ( 2014)), it is explained as follows.

  “For the measurement of the fouling potential (FP), a hydrophobic PVDF membrane (GVHP manufactured by Millipore, diameter: 25 mm) having a nominal pore size of 0.22 μm is used. Perform pressure filtration with a pump.

  Filtration is performed by constant-rate filtration (membrane permeation flux 20 m / day) while rotating the stirrer of the cell at 1,450 rpm. After the membrane differential pressure has increased to some extent, the membrane is removed from the cell and 1% -shu Acid cleaning (cleaning time 60 minutes, cleaning temperature about 20 ° C.) and sponge cleaning of the membrane surface are performed. After washing, the membrane is attached to the cell again, filtered with GVHP membrane filtered water of the test water, and the membrane differential pressure is measured again.

A value obtained by dividing the difference between the membrane differential pressure and the membrane differential pressure at the start of filtration (m-Aq at 25 ° C.) by the total amount of filtered water (m ³ / m ² -membrane) is defined as fouling potential (FP). doing. Note that the sample water is preliminarily filtered through a 0.45 μm membrane filter to remove the turbidity component and then tested. "

  Next, the operation of filtering a predetermined amount of at least three types of filtration target water using the membrane filtration system 10 is performed while exchanging the separation membrane 14 for each filtration target water. Next, FEEM is created about each separation membrane 14 used for filtration.

Then, for the created FEEM, for example, the integrated values P1 ⁱ and P2 ⁱ of the region P1 and the region P2 are calculated, the calculated integrated value is set as the Y axis, and the calibration curve is generated using the FP of each filtration target water as the X axis. To do. This calibration curve is shown in FIG. 6 (the calibration curve creation step S201). The figure shows a calibration curve created from the correlation between the fluorescence intensity (calculated integral value) and the FP value described later.

[Membrane Blocking Index Value Determination Step (S202)]
Next, the membrane occlusion index value determination step S202 will be described. In this step, the membrane to be filtered whose membrane occlusion index value (that is, FP value) is unknown is subjected to membrane filtration under the same conditions as in the calibration curve creating step S201 using the membrane filtration system 10, and the separation membrane used for membrane filtration Create an FEEM for 14.

Then, for the created FEEM, as in step S201, for example, the integral values P1 ⁱ and P2 ⁱ of the region P1 and the region P2 are calculated.

  As shown in FIG. 6, this integrated value is applied to the calibration curve created in step S201 to determine FP.

  Therefore, according to the water quality evaluation method for filtration target water according to the present embodiment, measurement of membrane fouling-causing substances (polymer substance group called biopolymer, polysaccharide-like substance) in filtration target water is usually an advanced analytical instrument. When a long-term measurement is required, a calibration curve is created in advance from the correlation between the FEEM and the membrane occlusion index (FP) that can be easily created by the separation membrane contamination analysis method according to the above embodiment. Thus, the membrane occlusion index value of the filtration target water can be easily determined by creating the FEEM for the filtration target water whose membrane occlusion index value (FP value) is unknown. Therefore, it becomes possible to evaluate the quality of water to be filtered easily and quickly.

  Further, in the method for analyzing the contamination state of the separation membrane 14 according to the present embodiment, the filtration target water is subjected to membrane filtration using one separation membrane, and the separation state of the separation membrane is analyzed. The present invention is not limited to the above, and various modifications are possible.

  Hereinafter, a modified example of the separation membrane contamination state analysis method according to the present embodiment will be described with reference to FIG. 7 using a membrane filtration system in which the arrangement of the separation membrane is changed as an example. In FIG. 7, the same elements as those in the embodiment shown in FIG. 1 described above are denoted by the same reference numerals, and the description thereof is omitted. Further, in FIG. 7, description of the spectrofluorophotometer 20 and the near-infrared light spectrophotometer 40 is omitted. FIG. 7A is a schematic diagram showing the arrangement of separation membranes in a membrane filtration system used in one modification of the separation membrane contamination analysis method according to this embodiment, and FIG. It is a schematic diagram which shows arrangement | positioning of the separation membrane in the membrane filtration system used for the other modification of the contamination state analysis method of the separation membrane which concerns on a form.

  In one modified example, as shown in FIG. 1A, the separation membrane 14-1 and the separation membrane 14-2 are arranged in parallel in the immersion tank 12, and in the other modified example, As shown to (B), in the immersion tank 12, the separation membrane 14-3 and the separation membrane 14-4 are arrange | positioned in series.

  In one modified example and another modified example, the separation membranes 14-1 to 14-4 are ultrafiltration membranes (UF) and microfiltration membranes (MF) as in the above embodiment for the purpose of water purification treatment in the waterworks business. ) Is selected.

  Specifically, for example, the separation membrane 14-1 and the separation membrane 14-3 are ultrafiltration membranes (UF) having a pore size of 0.45 μm, and the separation membrane 14-2 and the separation membrane 14-4 have a pore size of 0. 0.01 μm.

  Thereafter, membrane filtration of water 1 to be filtered, and separation membranes 14-1 to 14-4 after membrane filtration are analyzed by fluorescence spectroscopy and near infrared spectroscopy.

  Therefore, according to one modified example, from the analysis result of the separation membrane 14-1, it is possible to analyze a component having a particle diameter of 0.45 μm or more and contributing to the membrane blockage, and from the analysis result of the separation membrane 14-2. In addition, it is possible to analyze components that contribute to the blockage of the film having a particle size of less than 0.45 μm to 0.01 μm or more. That is, by using separation membranes having different pore sizes, it is possible to obtain more detailed information about the particle size of the membrane blocking component. Thereby, it is a glycoprotein having a particle size of about 0.01 to 1 μm and is considered to be involved in membrane fouling (TEP (transparent extracellular polymer), EPS (extracellular polymer), etc.) More accurate analysis is possible.

  Further, according to another modified example, the analysis of the component having a particle diameter of 0.45 μm or more from the analysis result of the separation membrane 14-3 and contributing to the membrane blockage is performed based on the analysis result of the separation membrane 14-4. It is possible to analyze each component that is 0.01 μm or more and contributes to the blockage of the membrane.

  As described above, it is possible to obtain more detailed information on the particle size of the membrane blocking component by the difference in the pore size of the separation membrane and the arrangement of the separation membrane in the flow path.

  In addition, the information about the membrane blocking component obtained by the above modification is not limited to information about the particle size. For example, it is possible to use two types of separation membranes having different hydrophilicity. According to this, it is possible to obtain information on the difference in hydrophilicity of the membrane blocking component by utilizing the difference in hydrophilicity of the separation membrane.

  Furthermore, although the separation state analysis method for the separation membrane according to the present modification is implemented using a method in which the arrangement of the separation membrane in the membrane filtration system 10 is changed, the use of the membrane filtration system 10 is not essential. That is, any membrane filtration system may be used as long as it is a membrane filtration system that performs filtration of water to be filtered with at least two types of separation membranes.

(Second Embodiment)
A method for analyzing the state of contamination of a separation membrane according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is a block diagram of the fluorescence spectrophotometer 60, and FIG. 9 is a diagram for explaining a method for analyzing the contamination state of the separation membrane according to the present embodiment. In the present embodiment, the same elements as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In this embodiment, analysis by fluorescence spectroscopy is performed. As shown in FIG. 8, the spectrofluorometer 60 used in the present embodiment is different from the first embodiment in that it has a sample insertion portion 62 for inserting a sample to be analyzed. A sample fixing plate 70 for fixing the sample is inserted into the sample insertion portion 62.

  As shown in FIG. 9A, the sample fixing plate 70 is a plate-like body having a rectangular hole 72 at a substantially central portion, and is substantially at the center in the length direction in the horizontal direction of the hole 72 in the drawing. A pair of fixing pins 74 having a curved recess 74a are provided.

  Moreover, in this Embodiment, the flow path 3 is common in 1st Embodiment. That is, the filtration target water 1 is filtered by the separation membrane 14 in the immersion tank 12 to become the filtrate 2.

  Hereinafter, the method for analyzing the contamination state of the separation membrane according to the present embodiment will be described mainly with respect to differences from the first embodiment.

  First, prior to the implementation of the method for analyzing the contamination state of the separation membrane 14, the liquid feed pump 16 is activated to filter a predetermined amount of the filtration target water 1 (river water).

[Resection Step (S301)]
In the excision step S301, as shown in FIG. 9A, a part of the hollow fiber 14b of the separation membrane 14 after the filtration is excised. The length to be cut may be a length that can be fixed by the fixing pin 74.

[Fixing step (S302)]
In the fixing step S302, the outer peripheral surface of the cut hollow fiber 14b is brought into contact with the recess 74a of the fixing pin 74, and the hollow fiber 14b is fixed on the plate. At this time, as shown in FIG. 9B, the hollow fiber 14b crosses the hole 72 (the fixing step S302).

  After the fixing step, the plate 70 is inserted into the sample insertion portion 62 of the spectrofluorometer 60.

[Irradiation process (S303)]
Next, the irradiation step S303 will be described. In a state where the plate 70 is inserted into the sample insertion portion 62, the spectrofluorometer 60 is turned on and activated. Thereby, in the spectrofluorometer 60, the control unit 38 sends a signal to the light irradiation unit 32. With this signal, as shown in FIG. 9B, the light irradiation unit 32 has an excitation wavelength of 220 nm to 200 nm in the direction of the arrow 200, that is, in the insertion direction of the hole 72 at a site crossing the hole 72 of the hollow fiber 14 b. The excitation light of 600 nm is sequentially irradiated (irradiation step S303).

  Thereafter, similarly to the first embodiment, the reception / spectroscopy unit 34 receives the fluorescence, the FEEM creation unit 36 creates the FEEM, and the contamination state of the separation membrane 14 is analyzed.

  Therefore, according to the present embodiment, the pretreatment for analysis is completed by excising a part of the separation membrane 14 and fixing it to the plate 70, and the analysis operation is performed on a part of the separation membrane 14 fixed to the plate 70. It is substantially performed by irradiating. Therefore, preprocessing and analysis operation are simplified, analysis time is shortened, and simple and quick analysis is possible.

  At the same time, since the separation membrane 14 is subjected to analysis using fluorescence spectroscopy as in the first embodiment, analysis errors, detection limits, etc. due to the influence of the substance present in the filtration target water 1 and the concentration of the substance. The problem can be avoided. Further, by analyzing the separation membrane 14, the influence of components that permeate the membrane on the analysis is eliminated, and only the membrane blocking component captured by the separation membrane 14 can be selectively analyzed.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of invention. For example, in the first embodiment, fluorescence spectroscopy and near infrared spectroscopy are used, and in the second embodiment, fluorescence spectroscopy is used. However, the present invention is not limited to this. Only spectroscopy may be used.

  Moreover, in the said embodiment, although at least 1 or more area | region of area | region AP1, P1, P2, H1, and H2 is used in the FEEM analysis process among the produced FEEM, it is essential to use the said area | region. Not that. That is, the FEEM as shown in FIG. 4 can be used in the FEEM analysis process as it is.

  According to this, for example, from the FEEM created from the analysis by the fluorescence spectroscopy of the separation membrane to which the known membrane blocking component is adhered and the analysis by the fluorescence spectroscopy of the separation membrane 14 in which a predetermined amount of the filtration target water 1 is filtered. It is also possible to compare the created FEEM, identify the membrane blockage component adhering to the separation membrane, and estimate the amount of the membrane blockage component from the ratio of the common points and the difference points of the waveform patterns.

  Furthermore, you may use together this invention and a nano particle meter. Many nanoparticle meters provide information on the size of particles of about 10 to 400 nm and information on charges such as zeta potential, but information on the properties of polymers such as polysaccharides and proteins cannot be obtained. It is more preferable to use the present invention in combination with such a nanoparticle meter, because information on both the quality and size of the membrane fouling substance and information on participation in filtration resistance can be obtained.

  The measuring method of the nanoparticle meter is not particularly limited, and is a nanoparticle tracking analysis method (NTA or PTA), a laser-induced breakdown detection method (LIDB), an electric resistance nanopulse method (TRPS, commonly known as qNano), dynamic Any of light scattering methods (DLS) may be used.

  Hereinafter, the present invention will be described with reference to examples.

1. Filtration of target water The water treatment in the present example assumes water treatment for purifying raw water to obtain tap water, and river water was used as raw water.

About 1 liter of water to be filtered (river water) was filtered using a separation membrane (flat membrane, pore diameter 0.22 μm) made of PVDF.
2. Analysis of the state of contamination of the separation membrane by fluorescence spectroscopy For the analysis of the state of contamination of the separation membrane, a spectrofluorometer (manufactured by Hitachi, Ltd.) that can also be used in the membrane filtration system 10 according to the present embodiment was used.

  Excitation light was applied to the surface of the separation target water side of the separation membrane obtained by filtering the filtration target water, and irradiation of the excitation light to the separation membrane and reception and spectroscopy of fluorescence from the separation membrane were performed to prepare an FEEM.

  FIG. 10 shows the created FEEM. From the FEEM created in this way, it was shown that the contamination state of the separation membrane can be analyzed.

1 Water to be filtered 3 Channel 10 Membrane filtration system 14 Separation membrane 20 Spectrofluorometer (spectrophotometer)
22 Holder 26 Excitation light transmission means (one light transmission means)
28 Fluorescence transmission means (other light transmission means)
30 Spectral Fluorometer Main Body (Spectrophotometer Main Body)
40 Near-infrared spectrophotometer (spectrophotometer)
42 Holder 44 Near-infrared light transmission means (one light transmission means)
46 Light transmission means (other light transmission means)
50 Near-infrared spectrophotometer body (spectrophotometer body)
70 Plate 72 Hole

Claims (7)

A filtration step in which a separation membrane is provided in a flow path of water to be filtered in water treatment, and the filtration target water is filtered by the separation membrane;
A light irradiation step of irradiating the separation membrane with excitation light from a spectrophotometer used for fluorescence spectroscopy;
Fluorescence spectroscopy step of causing the spectrophotometer to receive and split the fluorescence from the separation membrane,
FEEM creation step of creating a three-dimensional excitation fluorescence matrix spectrum (FEEM) based on the information about the wavelength of the excitation light and the information about the wavelength of the dispersed fluorescence;
An FEEM analysis step of analyzing the state of contamination of the separation membrane based on the relationship between the integrated value of fluorescence intensity in a predetermined region of the created FEEM and the total amount of filtered water;
A method for analyzing the contamination state of a separation membrane, comprising:   In the FEEM creation step, a contour map of a three-dimensional spectrum represented by an excitation wavelength Ex (Y axis), a fluorescence wavelength Em (X axis), and a fluorescence intensity (Z axis) is created according to the fluorescence intensity. The method for analyzing a contamination state of a separation membrane according to claim 1. The FEEM analysis process includes the FEEM to be created.
Region AP1 partitioned into a range of fluorescence wavelengths 290 nm to 330 nm and excitation wavelengths 220 nm to 240 nm, region P1 partitioned into a range of fluorescence wavelengths 290 nm to 320 nm and excitation wavelengths 265 nm to 295 nm, fluorescence wavelengths 320 nm to 395 nm, and excitation wavelengths 245 nm to The integrated value of the fluorescence intensity with respect to the total amount of filtered water in at least one of the regions P2 partitioned in the range of 295 nm, the region H1 partitioned in the range of the fluorescence wavelength of 395 nm to 480 nm and the excitation wavelength of 250 nm to 295 nm, and the fluorescence wavelength Finding the integral value of the fluorescence intensity with respect to the total amount of filtered water in at least one of the regions H2 partitioned into a range of 395 nm to 520 nm and an excitation wavelength of 300 nm to 375 nm,
2. It is determined that the film is in the final stage of fouling when the increase rate of the integral value of the regions H1 to H2 is larger than the increase rate of the integral value of the regions AP1 and P1 to P2. Alternatively, the method for analyzing the contamination state of the separation membrane according to 2. A method for evaluating the quality of water to be filtered in water treatment,
A calibration curve is created from the correlation between the integral value of the FEEM and a known membrane blockage index value from the FEEM creation step in the separation membrane contamination state analysis method according to any one of claims 1 to 3. Calibration curve creation process,
A membrane filtration was performed by the same method as the separation membrane contamination state analysis method used in the calibration curve creation step for the filtration target water with an unknown membrane blockage index value, and the FEEM of the separation membrane subjected to the membrane filtration was obtained. A membrane occlusion index value determining step of applying an integral value of FEEM to the created calibration curve to determine a membrane occlusion index value;
A method for evaluating the quality of water to be filtered. A membrane filtration system for conducting a contamination state analysis method for a separation membrane that is provided in a flow path of water to be filtered in water treatment and introduces and filters the water to be filtered.
A holder removably attached to the surface to be filtered of the separation membrane,
An excitation light irradiating unit that is provided in the holder and irradiates the separation film with excitation light;
A fluorescence spectroscopic unit that is provided in the holder and separates fluorescence emitted from the separation membrane that has absorbed the excitation light with respect to the filtered separation membrane;
Based on the excitation light wavelength information of the excitation light and the spectral fluorescence wavelength information, the three-dimensional excitation represented by the excitation wavelength as the Y-axis, the fluorescence wavelength as the X-axis, and the fluorescence intensity as the Z-axis. An FEEM creation unit for creating a fluorescence matrix spectrum (FEEM),
The membrane filtration system characterized in that the state of contamination of the separation membrane can be grasped from the change in the integrated value of the fluorescence intensity in the fluorescence wavelength region of the created FEEM. A membrane filtration system for conducting a contamination state analysis method for a separation membrane that is provided in a flow path of water to be filtered in water treatment and introduces and filters the water to be filtered.
A holder removably attached to the surface to be filtered of the separation membrane,
A near-infrared light irradiating unit provided on the holder for irradiating the separation membrane with near-infrared light;
An emission light spectroscopic unit that splits light emitted from the separation membrane that has absorbed the near-infrared light; and
A two-dimensional absorption spectrum creation unit that creates a two-dimensional absorption spectrum of absorbance-spectral wavelength based on the spectrally emitted light wavelength information;
By the two-dimensional absorption spectrum creation unit, asking the absorption spectrum A ₁ by measurement after filtration of the separation membrane, the absorption spectrum A ₀ by the measurement before filtration of the separation membrane, the absorption spectrum of the by difference, the separation membrane A membrane filtration system characterized in that a contamination state of the separation membrane can be ascertained by obtaining a spectrum derived from a substance captured by filtration. The membrane filtration system according to claim 5,
A near-infrared light irradiating unit provided on the holder for irradiating the separation membrane with near-infrared light;
An emission light spectroscopic unit that receives and separates light emitted from the separation film that has absorbed the near-infrared light; and
A two-dimensional absorption spectrum creation unit that creates a two-dimensional absorption spectrum of absorbance-spectral wavelength based on the spectrally emitted light wavelength information,
By the two-dimensional absorption spectrum creation unit, asking the absorption spectrum A ₁ by measurement after filtration of the separation membrane, the absorption spectrum A ₀ by the measurement before filtration of the separation membrane, the absorption spectrum of the by difference, the separation membrane By obtaining a spectrum derived from the substance captured by filtration of the filter, it is possible to grasp the contamination state of the separation membrane,
Using both spectroscopic methods, the protein structure part is detected by the analysis by the fluorescence spectroscopy, and the sugar structure part is detected by the near infrared spectroscopy method of irradiating the filtered separation membrane with near infrared light. A membrane filtration system characterized by grasping a contamination state of the separation membrane.

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