JP2018008192A - Foulant quantification method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a foulant quantification method capable of quantifying a foulant affecting a solid-liquid separation membrane at an operation site. SOLUTION: A membrane separator for quantifying foulant concentration is immersed in a foulant-containing solution to set a filtration rate, and the rate of increase in suction pressure after quantitative filtration for a predetermined time with the membrane separator is measured separately. The foulant concentration in the foulant-containing solution is measured by a method that does not use a membrane separator, and a calibration line showing the correlation between the foulant concentration and the increase rate of the suction pressure is prepared, and the measurement target is measured. The suction pressure increase rate of the foulant-containing solution is measured by the same method as described above, and the foulant concentration is quantified using the calibration line. [Selection diagram] Fig. 1

Description

  The present invention relates to a method for determining a foulant in a foulant-containing solution.

  Conventionally, as a method for treating water to be treated such as organic waste water, a method for solid-liquid separation of water to be treated has been widely practiced along with purification using activated microorganisms (activated sludge treatment). As a method of solid-liquid separation, sand filtration, gravity precipitation, or the like is performed. However, these solid-liquid separation methods have a problem that the SS (floating matter) concentration of the treated water to be obtained tends to be high and a large site is required.

  As a method for solving such problems, in recent years, a method of solid-liquid separation of water to be treated using a separation membrane module (membrane separation device) equipped with a separation membrane such as a microfiltration membrane and an ultrafiltration membrane has been used. It has been. When water to be treated is filtered using such a separation membrane, treated water containing almost no SS is obtained. A series of wastewater purification treatments in which solid sludge separation is performed using a separation membrane after the activated sludge treatment is called a membrane separation activated sludge method, and an apparatus for performing this method is called a membrane separation activated sludge device.

However, when the membrane separation activated sludge apparatus is used, the separation membrane may be contaminated and clogged if the treatment is continued. Such contamination of the separation membrane is called fouling, and it is known that the processing capability of the separation membrane is reduced. When fouling occurs, it becomes difficult for the waste water to pass through the separation membrane, and the transmembrane pressure difference of the separation membrane increases. In particular, when the BOD (biochemical oxygen demand) load suddenly increases or when environmental stress is applied to microorganisms in the low temperature period such as winter, organic substances are not sufficiently decomposed by the microorganisms. Filtration-inhibiting components that contaminate the water deposit on the separation membrane, whereby the transmembrane pressure difference increases rapidly, and the processing capacity is extremely deteriorated.
Here, the foulant means a filtration inhibiting component that contaminates the separation membrane and causes fouling. The foulant includes a soluble foulant and / or a non-soluble foulant. Examples of the soluble foulant include polymer solutes (such as sugar and protein) and inorganic salts, and examples of the non-soluble foulant include hardly soluble components, colloids, and fine solids.

  When the transmembrane pressure rises rapidly, it is necessary to recover the treatment capacity by washing the separation membrane. Generally, a method is known in which the operation of the separation membrane is stopped by interrupting the operation once and flowing water or a chemical solution through the separation membrane so as to be in the opposite direction to the filtration. Further, when the degree of contamination is high, a method is known in which the separation membrane is lifted from the activated sludge tank and washed by immersing the separation membrane in a chemical solution. However, there is a problem that the operation of the membrane separation activated sludge apparatus cannot be continued with any cleaning method.

  Therefore, as a method for monitoring the deterioration of activated sludge properties (increased transmembrane pressure difference) due to increased foulants in activated sludge, a correlation with the filtration characteristics of activated sludge obtained by filtering activated sludge with filter paper has been proposed. Quantitative analysis of soluble microorganism metabolite (SMP) used (for example, see Patent Document 1), organic substances contained in activated sludge supernatant liquid and separation membrane permeated liquid using TOC meter, COD meter, ultraviolet absorption photometer (total Sugar (total protein, uronic acid) (for example, see Patent Document 2) and total sugar contained in an activated sludge supernatant using a phenol-sulfuric acid method (for example, see Patent Document 3) have been proposed.

JP 2011-67818 A Japanese Unexamined Patent Publication No. 2012-200351 JP 2007-75754 A

However, in the method described in Patent Document 1, the filtration characteristics of the activated sludge obtained by filtering with filter paper are essentially different from the filtration characteristics when filtering with the separation membrane used in the membrane separation activated sludge apparatus. Therefore, there is a problem that SMP acting as a foulant of the separation membrane cannot be accurately quantified.
Moreover, in the method of patent document 2 and patent document 3, since the foulant only in the activated sludge supernatant liquid was quantified, there existed a subject of underestimating the organic substance density | concentration which acts as a foulant of a separation membrane. .
The phenol-sulfuric acid method used as a method for quantifying total sugar requires the use of deleterious substances-designated reagents such as phenol and concentrated sulfuric acid, and sufficient consideration is necessary to ensure work safety. From the viewpoint of equipment, the implementation of the membrane separation activated sludge apparatus at the operation site was required to be minimal.

  The present inventors have found that there is a correlation between the rate of increase in suction pressure when the solid-liquid separation membrane is immersed in a foulant-containing solution and quantitatively filtered, and the foulant concentration in the foulant-containing solution. According to the present invention, only the foulants that affect the solid-liquid separation membrane can be quantified, the frequency of use of reagents such as deleterious substances can be reduced, and the membrane separation apparatus can be implemented at the operation site. Thus, the inventors have found that a high effect can be obtained as a method for quantifying the foulant concentration (hereinafter also referred to as a foulant quantification method), and the present invention has been achieved.

That is, this invention has the following aspect.
[1] A method for quantitatively determining a foulant, comprising the following steps.
<Calibration curve creation process>
(I) a step of immersing a membrane separator for foulant concentration determination in a foulant-containing solution;
(Ii) setting a filtration rate of the membrane separator for foulant determination;
(Iii) a step of measuring an increase rate of suction pressure when the membrane separator for quantifying the foulant concentration is quantitatively filtered over a predetermined time in the step (ii);
(Iv) a step of measuring a foulant concentration in the foulant-containing solution by a method not using a membrane separation device, and creating a calibration curve indicating a correlation between the foulant concentration and the increase rate of the suction pressure;
<Foulant determination process>
(V) a step of immersing a membrane separator for foulant concentration determination in a foulant-containing solution;
(Vi) setting the filtration rate of the membrane separator for foulant determination;
(Vii) a step of measuring an increase rate of suction pressure when the membrane separator for foulant determination is quantitatively filtered over a predetermined time in the step (vi);
(Viii) quantifying the foulant concentration in the foulant-containing solution from the calibration curve prepared in the step (iv) and the rate of increase measured in the step (vii);
[2] In the steps (ii) and (vi) described in [1], a filtration rate is set in the range of LV 0.2 to 2.0 m / day, and quantitative filtration is performed over 1 minute or more. Method for the determination of foulants.
[3] A membrane separator for foulant determination, a pump for quantitatively filtering the membrane separator,
A foulant quantification apparatus comprising a suction pressure measurement unit and a calculation unit arranged in the membrane separation device.

  According to the present invention, it becomes possible to quantify only the foulant that affects the solid-liquid separation membrane by reducing the frequency of use of reagents such as deleterious substances. In addition, since the membrane separator can be implemented at the operation site, it is possible to immediately grasp the deterioration of activated sludge properties (increased transmembrane differential pressure) due to increased foulants, increasing the amount of aeration and continuous treatment It is possible to effectively implement measures for suppressing the increase in the differential pressure, such as lowering the filtration rate and washing the membrane separation device, at an appropriate timing.

It is a schematic block diagram which shows one Embodiment of the foulant fixed_quantity | assay method in the activated sludge which concerns on this invention. 4 is a graph showing a correlation between a foulant concentration and an increase rate of a suction pressure in Example 1. It is a graph which shows the correlation with the foulant density | concentration in Example 2, and the raise rate of a suction pressure.

  Hereinafter, although the embodiment is shown and demonstrated about the foulant determination method in the foulant containing solution of this invention, this invention is not limited to this.

The present invention is a method for quantifying a foulant concentration, comprising the following steps.
<Calibration curve creation process>
(I) a step of immersing a membrane separator for foulant concentration determination in a foulant-containing solution;
(Ii) setting a filtration rate of the membrane separator for foulant determination;
(Iii) a step of measuring an increase rate of suction pressure when the membrane separator for quantifying the foulant concentration is quantitatively filtered over a predetermined time in the step (ii);
(Iv) a step of measuring a foulant concentration in the foulant-containing solution by a method not using a membrane separation device, and creating a calibration curve indicating a correlation between the foulant concentration and the increase rate of the suction pressure;
<Foulant determination process>
(V) a step of immersing a membrane separator for foulant concentration determination in a foulant-containing solution;
(Vi) setting the filtration rate of the membrane separator for foulant determination;
(Vii) a step of measuring an increase rate of suction pressure when the membrane separator for foulant determination is quantitatively filtered over a predetermined time in the step (vi);
(Viii) quantifying the foulant concentration in the foulant-containing solution from the calibration curve prepared in the step (iv) and the rate of increase measured in the step (vii);

[Step (i)]
Step (i) in the present invention is a step of immersing a membrane separator for quantifying the foulant concentration in the foulant-containing solution.

(Foulant-containing solution)
The foulant in the present invention is not particularly limited as long as it is a substance that adsorbs to the film surface. Generally, soluble foulants include polymeric solutes (such as sugars and proteins) and inorganic salts. Examples of non-soluble foulants include hardly soluble components, colloids, and fine solids.
When foulant adheres inside the pores of the separation membrane used in the membrane separation device, the pore diameter becomes small, so that the membrane resistance during water passage increases. As time increases, pressure loss due to hole blockage increases rapidly, leading to a sudden increase in suction pressure. In the examples, the amount of sugar in the activated sludge is quantified, but with regard to other foulants, if the component is captured by the separation membrane, an increase in the pressure loss of the separation membrane and an increase in the suction pressure can be seen. Quantification is possible in the same way.

(Membrane separator)
The membrane separation apparatus used in the present invention has a separation membrane.
Although it does not specifically limit as a kind of separation membrane, From a viewpoint of water treatment performance, a microfiltration membrane (MF membrane) or an ultrafiltration membrane (UF membrane) is preferable.
Examples of the shape of the separation membrane include a hollow fiber membrane, a flat membrane, a tubular membrane, and a bag-like membrane. Of these, hollow fiber membranes are preferred because they can be highly integrated when compared on a volume basis.

  Examples of the material of the separation membrane include organic materials (cellulose, polyolefin, polysulfone, polyvinyl alcohol, polymethyl methacrylate, polyvinylidene fluoride, polytetrafluoroethylene, etc.), metals (stainless steel, etc.), inorganic materials (ceramics, etc.). It is done. It is appropriately selected depending on processability, chemical resistance, drainage properties, and the like.

  The pore diameter of the separation membrane may be appropriately selected according to the purpose of treatment. For example, in the membrane separation activated sludge method (MBR), the pore size of the separation membrane is preferably 0.001 to 3 μm. If the pore diameter is less than 0.001 μm, the resistance of the membrane tends to increase. If the pore diameter exceeds 3 μm, the sludge cannot be completely separated, and the water quality of the treated water (permeated water) may be deteriorated. The pore size of the separation membrane is more preferably 0.04 to 1.0 μm, which is the range of the microfiltration membrane.

[Step (ii)]
Step (ii) in the present invention is a step of setting the filtration rate of the membrane separator for foulant determination.
Here, the filtration rate (LV) is preferably set in the range of 0.2 to 2.0 m / day, and more preferably set in the range of 0.4 to 1.5 m / day. When the LV is 0.2 m / day or more, the foulant is captured by the membrane separation device 2, so that the soluble foulant can be detected from the rate of increase in the suction pressure of the membrane separation device 2. If the LV is 2.0 m / day or less, suspended substances in the activated sludge are not easily trapped on the membrane surface (clogging is unlikely to occur), so that only the foulant is trapped in the membrane separator, and the dissolved foulant is accurately Accurate quantification is possible.
Further, the filtration flow rate is calculated from the separation membrane area of the membrane separation device, and the flow rate of the metering filtration pump is set. An example of the calculation method is shown below.
Filtration flow rate [m ³ / day] = LV [m / day] × separation membrane area [m ² ]
In addition, LV means the speed of the treated water that passes through the separation membrane per unit time and unit area.

[Step (iii)]
The step (iii) in the present invention is a step of measuring the rate of increase in suction pressure when the membrane separator for quantifying the foulant concentration is quantitatively filtered over a predetermined time in the step (ii).

In the embodiments of the present invention to be described later, a quantitative filtration pump is used. The metering pump is connected to a membrane separator. The inside of the membrane separator is depressurized by the quantitative filtration pump, and the foulant-containing solution and the permeated water are subjected to solid-liquid separation.
When the pressure is reduced by the membrane separator being sucked by the quantitative filtration pump, the suction pressure increases with the suction time. It is preferable to select a metering filtration pump that does not decrease the filtration flow rate as the suction pressure of the membrane separator increases. By selecting a pump whose filtration flow rate is not affected by fluctuations in the suction pressure, stable quantitative filtration is possible, and the accuracy of measuring the rate of increase in suction pressure and determining the foulant in the foulant-containing solution is improved. For example, a syringe pump or the like.

[Step (iv)]
In the step (iv) of the present invention, a foulant concentration in the foulant-containing solution is measured by a method that does not use a membrane separation device, and a calibration curve indicating the correlation between the foulant concentration and the increase rate of the suction pressure is created. It relates to the process.

Here, the calibration curve creation process showing the correlation between the foulant concentration and the increase rate of the suction pressure will be described.
In order to create a calibration curve, the foulant in the foulant-containing solution is quantified by a method that does not use a membrane separator in combination with the measurement of the suction pressure increase rate according to the present invention.
Here, the method that does not use a membrane separator is not particularly limited as long as it does not use a membrane separator and can quantify the foulant concentration. For example, a TOC meter, a COD meter, an ultraviolet absorptiometer, a phenol Examples include the sulfuric acid method.
Here, in the calibration curve creation process of the present invention, at least three points or more of the sample, the rate of increase in suction pressure and the amount of foulant are determined by a method not using the membrane separation device, and the increase in foulant concentration and suction pressure is performed. Create a calibration curve showing the correlation with the rate.
After the calibration curve is created, the foulant concentration can be calculated from the rate of increase in the suction pressure of the membrane separator without using the method without using the membrane separator.

[Step (v)]
Step (v) in the present invention is a step of immersing a membrane separator for quantifying the foulant concentration in the foulant-containing solution.
Said process (v) can be implemented by the method similar to the above-mentioned process (i).

[Step (vi)]
Step (vi) in the present invention is a step of setting the filtration rate of the membrane separator for foulant determination.
Said process (v) can be implemented by the method similar to the above-mentioned process (ii).

[Step (vii)]
The step (vii) in the present invention is a step of measuring the rate of increase in suction pressure when the membrane separator for foulant determination is quantitatively filtered over a predetermined time in the step (vi).
Said process (vii) can be implemented by the method similar to the above-mentioned process (iii).

[Step (viii)]
The step (viii) in the present invention is a step of quantifying the foulant concentration in the foulant-containing solution from the calibration curve created in the step (iv) and the increase rate measured in the step (vii).
In the calibration curve created in the step (iv), for example, as shown in FIG. 2 or 3, there is a correlation between the foulant concentration and the increase rate of the suction pressure. Therefore, if a calibration curve is first created, then the foulant concentration can be calculated from the rate of increase in the suction pressure of the membrane separation device without using a method that does not use a membrane separation device.
Thereby, it becomes possible to reduce the frequency of use of reagents such as deleterious substances and to quantify the foulant of the foulant-containing solution (for example, in activated sludge) that affects the separation membrane.

Here, the embodiment of the present invention will be specifically described with reference to FIG.
FIG. 1 shows an example of an apparatus suitably used in the foulant quantification method of the present invention.
The embodiment of the present invention includes a membrane separation tank 1, a membrane separation apparatus 2 provided in the membrane separation tank 1 and provided with a separation membrane, a quantitative filtration pump 3 for sucking the membrane separation apparatus 2, and a membrane separation apparatus. 2, a suction pressure measuring unit 4 that measures the suction pressure of 2, a calculation unit 5 disposed in the membrane separation device 2, and a liquid to be measured 8.
An aeration apparatus 6 or a stirring apparatus 7 is installed below the membrane separation apparatus 2 so that the measured liquid 8 in the membrane separation tank 1 does not settle during the test, and the measured liquid 8 in the membrane separation tank 1. The flow of is configured to be constant.

The membrane separation device 2 is disposed in the membrane separation tank 1 and is immersed in the measured liquid 8 (activated sludge). As the membrane separation device 2, a membrane separation device provided with the aforementioned separation membrane (filtration membrane) can be used.
In addition, when the same separation membrane as the separation membrane selected by the membrane separation activated sludge apparatus is selected and the present invention is carried out, it becomes possible to detect only the foulant captured by the separation membrane by the membrane separation activated sludge apparatus. So it is more preferable.
As the separation membrane of the membrane separation device 2, it is preferable to use an unused membrane or perform chemical cleaning for each measurement so that no foulant is accumulated in the separation membrane used for foulant determination.
Here, when using a separation membrane that has been subjected to chemical cleaning, it is more preferable to confirm in advance that the water permeability of the separation membrane has recovered to the same level as that of the unused membrane.

An aeration device 6 or a stirring device 7 is installed below the membrane separation device 2. It is preferable that the measured liquid 8 in the membrane separation tank 1 does not settle during the test, and the flow of the measured liquid 8 in the membrane separation tank 1 is constant.
Although it does not specifically limit as the aeration apparatus 6, A diffuser tube, a blower, etc. are mentioned. Examples of the material of the air diffuser include polycarbonate, polysulfone, polyethylene, polypropylene, acrylic resin, ABS resin, vinyl chloride resin, and other synthetic resins, and metals such as stainless steel. It is preferable that the installation position of the aeration device 6 is fixed and the amount of aeration is constant so that the aeration hitting the membrane separation device 2 is uniform for each measurement.
Although it does not specifically limit as the stirring apparatus 7, A magnetic stirrer etc. are mentioned. It is preferable that the number of rotations of the stirring device 7 be constant so that the flow of the liquid 8 to be measured in the membrane separation tank 1 becomes constant every measurement.

A suction pressure measurement unit 4 is connected between the membrane separation device 2 and the quantitative filtration pump 3, and the calculation unit 5 measures the rate of increase of the suction pressure per unit time. The suction pressure measurement unit 4 is not particularly limited, and examples thereof include a digital pressure sensor. The calculation unit 5 selects the data that can be converted into the rate of change per unit time of the measurement data in the suction pressure measurement unit 4. An example of the calculation unit 5 is a data logger. When the calculation unit 5 converts the calibration curve as a calibration curve, the rate of change in suction pressure per unit time (the slope of the straight line portion of the calibration curve) is the rate of increase in suction pressure.
The membrane separator 2 is sucked with a quantitative filtration pump 3 and quantitatively filtered over 1 minute or more. The suction pressure during that time is measured by the suction pressure measurement unit 4 and the calculation unit 5.
The graph in the range where 1 minute or more has passed since the start of suction is not affected by the pump's idle operation, the suction pressure fluctuation due to the air in the separation membrane, and the like, and thus becomes a stable straight line. By calculating the rate of increase of the suction pressure within a range where a stable straight line is obtained, the error is reduced, leading to an improvement in the accuracy of the determination of the soluble foulant in the activated sludge. Therefore, it is preferable to calculate the increase rate of the suction pressure in a range where one minute or more has passed since the start of suction.

According to the present invention, it is possible to quantify the foulant of a foulant-containing solution (for example, in activated sludge) that affects the separation membrane by reducing the frequency of use of reagents such as deleterious substances.
In addition, since the membrane separation activated sludge apparatus can be implemented at the operation site, the deterioration of the liquid to be measured (for example, activated sludge properties) due to the increase in foulant in the foulant-containing solution (for example, increase in transmembrane pressure difference) Therefore, it is possible to effectively implement measures for suppressing an increase in the differential pressure, such as an increase in the aeration amount, a reduction in the filtration speed of the continuous treatment, and a cleaning of the membrane separation device at an appropriate timing.

  Hereinafter, although an example and a comparative example explain the present invention in detail, the present invention is not limited to this.

(Permeability evaluation)
WF (unit time, unit area, amount of pure water per unit pressure) was used as an index for evaluating the water permeability of the separation membrane of the membrane separator.
WF was calculated from the permeation amount of pure water per unit time when a constant pressure was applied to the separation membrane.
WF [m ³ / m ² / hr / MPa] = permeated water amount [m ³ / hr] ÷ separation membrane area [m ² ] ÷ measured pressure [MPa]

Example 1
As the activated sludge, activated sludge from a wastewater test site that performs membrane-separated activated sludge treatment of domestic wastewater was used. Moreover, as a separation membrane used in the membrane separation apparatus, a hollow fiber membrane made of polyvinylidene fluoride for microfiltration having a nominal pore diameter of 0.05 μm (WF = 30 m ³ / m ² / hr / MPa in an unused state) is used. It was.
A syringe pump manufactured by YMC Co., Ltd. was used as the quantitative filtration pump. A digital pressure sensor manufactured by Keyence Co., Ltd. was used as the suction pressure measurement unit, and a data logger manufactured by Graphtec Co., Ltd. was used as the calculation unit.
An aeration apparatus was arranged below the membrane separation apparatus, and aeration from a polycarbonate aeration tube was always performed. The amount of air diffused was 100 Nm ³ / m ² · hr per projected area of the hollow fiber membrane part.
As the foulant-containing solution (measurement liquid), activated sludge having an activated sludge concentration of 6000 to 10000 mg / L was used.
The LV of the membrane separator was 1.0 m / day, and the filtration time was 10 minutes. The membrane separator was quantitatively filtered for 10 minutes, and the suction pressure during that time was measured. Thereafter, a graph was created with the horizontal axis representing the suction time and the vertical axis representing the suction pressure, and the rate of increase of the suction pressure per unit time was calculated. Chemical cleaning was performed for each measurement, or an unused film was used. The chemical cleaning was performed by immersing the separation membrane in a 0.3% sodium hypochlorite aqueous solution and keeping the temperature at 60 ° C. for 4 hours.
In order to grasp the correlation between the increasing rate of the suction pressure and the soluble foulant concentration in the activated sludge, the sugar concentration in the filtrate after the activated sludge was filtered through a filter paper was measured. The sugar concentration was measured by the phenol sulfuric acid method.
As shown in FIG. 2, a correlation was confirmed between the rate of increase in suction pressure when quantitatively filtering activated sludge and the sugar concentration in the activated sludge filter paper filtrate measured using the phenol sulfuric acid method. After the calibration curve in FIG. 2 is created, the sugar concentration can be calculated from the rate of increase in suction pressure. Therefore, the frequency of use of reagents such as deleterious substances can be reduced, and only sugars affecting the solid-liquid separation membrane can be quantified.

(Example 2)
The test was carried out under the same conditions as in Example 1 except that a stirring device was disposed below the membrane separation device. The stirring speed of the stirring device was 500 rpm.
As shown in FIG. 3, a correlation was confirmed between the rate of increase in suction pressure when the activated sludge was quantitatively filtered and the sugar concentration in the activated sludge filter paper filtrate measured using the phenol-sulfuric acid method. After creating the calibration curve in FIG. 3, the sugar concentration can be calculated from the rate of increase in suction pressure. Therefore, the frequency of use of reagents such as deleterious substances can be reduced, and only sugars affecting the solid-liquid separation membrane can be quantified.

1: Membrane separation tank 2: Membrane separation device 3: Metering filtration pump 4: Suction pressure measurement unit 5: Calculation unit 6: Aeration device 7: Stirrer 8: Foulant-containing solution (measuring solution)

Claims (3)

A method for quantitatively determining foulants, comprising the following steps.
<Calibration curve creation process>
(I) a step of immersing a membrane separator for foulant concentration determination in a foulant-containing solution;
(Ii) setting a filtration rate of the membrane separator for foulant determination;
(Iii) a step of measuring an increase rate of suction pressure when the membrane separator for quantifying the foulant concentration is quantitatively filtered over a predetermined time in the step (ii);
(Iv) a step of measuring a foulant concentration in the foulant-containing solution by a method not using a membrane separation device, and creating a calibration curve indicating a correlation between the foulant concentration and the increase rate of the suction pressure;
<Foulant determination process>
(V) a step of immersing a membrane separator for foulant concentration determination in a foulant-containing solution;
(Vi) setting the filtration rate of the membrane separator for foulant determination;
(Vii) a step of measuring an increase rate of suction pressure when the membrane separator for foulant determination is quantitatively filtered over a predetermined time in the step (vi);
(Viii) quantifying the foulant concentration in the foulant-containing solution from the calibration curve prepared in the step (iv) and the rate of increase measured in the step (vii);   The foulant according to claim 1, wherein in the steps (ii) and (vi) according to claim 1, a filtration rate is set in a range of LV 0.2 to 2.0 m / day, and quantitative filtration is performed over 1 minute. Quantitation method. A membrane separator for foulant determination;
A pump for quantitative filtration of the membrane separator;
Having a suction pressure measurement unit and a calculation unit arranged in the membrane separation device,
Foulant quantitative device.