JPH10314552A - Hollow fiber membrane cartridge for capturing protozoa and method for capturing and recovering protozoa - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module and a method for capturing and collecting protozoa contained in a test water in a short time and with high efficiency. SOLUTION: When capturing and recovering protozoa contained in a sample water, the sample water is passed through a hollow fiber membrane cartridge provided with a porous hollow fiber membrane having micropores having a maximum pore diameter of 2.0 μm or less, and filtered. After concentrating the test water on the primary side of the porous hollow fiber membrane, concentrated water containing protozoa and / or turbidity components containing protozoa deposited on the surface of the porous hollow fiber membrane are recovered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hollow fiber membrane cartridge for capturing protozoa for capturing and recovering protozoa contained in a test water, and a method for capturing and recovering protozoa.

[0002]

2. Description of the Related Art In recent years, cryptosporidium, which is a protozoan parasite in cattle, pigs, and the like, is often mixed in tap water to cause a large number of infected persons. The reason that Cryptosporidium is mixed into tap water is said to be due to the contamination of tap water sources by the flow of sewage from livestock farmers into surface water, but it has not been clarified yet.

[0003] Cryptosporidium is a pathogenic protozoan of the order Coccidiomycetes, and in the natural environment such as rivers and lakes, is called an oocyst (cyst in the case of Giardia, which is also a pathogenic protozoan of the order Coccidia), having a long diameter of 7 to 8 µm and a short diameter. Because it is wrapped in a 5-6 μm bale-shaped membrane, it is strong against chemicals and has no effect with ordinary chlorine disinfection, and it is very difficult to completely remove it in a water purification plant even if filtration such as coagulation and sedimentation is performed. is there.

[0004] The oocyst contains four sporozoids therein, and in the oocyst ingested into the body, the sporozoid is excysted in the intestine and parasitises the inner wall of the intestine. The main symptom of infected people is watery diarrhea, and people with weak immunity may die. A method for detecting protozoa contained in tap water is described in “Temporary Guideline for Cryptosporidium in Water Supply-Appendix 3” published by the Ministry of Health and Welfare on September 30, 1996.
"Temporary test method for detection of Cryptosporidium oocysts in tap water" describes a method for capturing and recovering oocysts.

[0005] Among them, an outline of a portion relating to capture and recovery of turbid matter in a test water is described below. 1. Collection of test water: 40 tap water, water distribution reservoir and clean water reservoir
About 10L of raw water such as river water should be collected. 2. Membrane surface capture: cellulose acetate disc filter (filter diameter 47 or 90 mm, pore diameter 1.2 μm
) Is set in a filter, and the sample water is filtered. 3. Extraction of captured matter: Insert the disk filter capturing the suspended matter into a precipitation tube (15 or 50 ml), add 99.5% acetone, and dissolve the filter. 4. Purification liquid replacement: Centrifugation is performed at 2500 to 3000 rpm for 10 minutes, and the acetone solution of the supernatant is removed by suction. Acetone is added again to the obtained sediment to re-suspend, and centrifugal sedimentation is repeated once or twice. Purified liquid (liquid obtained by filtering double-distilled water with a filter having a pore size of 0.45 μm or less) on the obtained sediment
And resuspended, followed by centrifugation in the same manner. 5. Replacement of PBS solution: After centrifugal precipitation with the purified solution, the supernatant was removed by suction, and PBS solution (phosphate buffered saline) was added.
After resuspension, centrifuge in the same manner. The supernatant is removed by suction, an appropriate amount of a PBS solution is added, and the suspension is resuspended to prepare a sample.

[0006] In order to capture and recover the parasites contained in the test water by such a method, it takes two to three hours from the start of filtration to the replacement of the PBS solution even if tap water is used. Thereafter, the captured matter is captured again on the filter, fluorescently stained by an indirect fluorescent antibody method, a preparation is prepared, and observed and counted by an epifluorescence microscope. In the case of a sample having a large amount of suspended substances, the captured matter is purified by a density gradient method using a sucrose solution before entering the staining step.

[0007]

However, when the protozoa are captured and recovered by the method described above, 1. The filtration speed is reduced early due to clogging of the filter. Since the membrane area of the filter is small, a large amount of test water cannot be passed efficiently.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of these inconveniences, and has been developed in a short time and with high efficiency.
The purpose of the present invention is to develop a hollow fiber membrane cartridge for capturing protozoa and a method for capturing and recovering protozoa for capturing and recovering protozoa contained in the test water.

That is, the gist of the present invention is that both ends of a porous hollow fiber membrane are opened and potted inside an outer cylinder, and a water sample is supplied to the outer cylinder on the outer surface side of the porous hollow fiber membrane. A protozoan-trapping hollow fiber membrane cartridge is provided with a water supply port and a water outlet for taking out permeated water by communicating with an open end of the porous hollow fiber membrane.

The gist of the present invention is that the both ends of the porous hollow fiber membrane are separately opened and potted inside the outer cylinder, and the outer cylinder is provided with a sample at one open end of the porous hollow fiber membrane. And a water outlet for taking out permeated water by communicating with the outer surface side of the porous hollow fiber membrane, and extracting concentrated water from another open end of the porous hollow fiber membrane. And a hollow fiber membrane cartridge for capturing protozoa.

Further, the gist of the present invention is to provide a hollow fiber membrane cartridge provided with a porous hollow fiber membrane having fine pores having a maximum pore diameter of 2.0 μm or less when capturing and recovering protozoa contained in test water. After passing the test water and filtering, the test water is concentrated on the primary side of the porous hollow fiber membrane, and then the concentrated water containing the protozoa and / or the protozoa deposited on the surface of the porous hollow fiber membrane are contained. A method for capturing and recovering protozoa, comprising recovering a turbidity component.

When the hollow fiber membrane cartridge is vibrated by a test tube stirrer or the like while passing test water through and filtering is performed, the turbidity component trapped on the membrane surface is shaken off, making it difficult to adhere to the membrane surface. preferable.

When the sample water is passed through the hollow fiber membrane cartridge, the sample water is passed for a certain time (or a fixed amount) and then stopped for a certain time. Are preferred because they are less likely to stick.

Further, it is preferable that the turbidity component hardly adheres to the membrane surface when the sample water is passed through while stirring or circulating the liquid phase in the primary space in the hollow fiber membrane cartridge and then filtered.

[0015] In addition, when the sample water is filtered by suctioning the secondary side of the porous hollow fiber membrane, especially when the protozoa is collected using river water or the like having high turbidity as the test water, the hollow sample is filtered. It is preferable that clogging of the yarn membrane does not easily occur.

It is preferable that the filtration of the sample water be performed at a transmembrane pressure difference of ² kg / cm ² or less, since the clogging of the surface of the porous hollow fiber membrane does not easily occur.

In recovering the turbidity component containing protozoa deposited on the surface of the porous hollow fiber membrane, the porous hollow fiber membrane is immersed in a washing solution, and the hollow fiber membrane portion is rinsed to remove the turbidity of the membrane surface. It is preferable to induce the components into the cleaning liquid, because the turbidity components fixed to the membrane surface and the turbidity components that have entered between the membranes can be induced.

Further, when recovering the turbidity component containing protozoa deposited on the surface of the porous hollow fiber membrane, the porous hollow fiber membrane is immersed in a cleaning solution in a cleaning solution tank, and the porous hollow fiber membrane is vibrated. Thus, when the turbidity component on the membrane surface is induced into the washing solution, the destruction of the protozoa and the like are reduced.

More preferably, in recovering the turbid components including protozoa deposited on the surface of the porous hollow fiber membrane, the porous hollow fiber membrane is immersed in a cleaning solution in an ultrasonic cleaner, and the membrane is subjected to ultrasonic cleaning. When the turbidity component on the surface is introduced into the cleaning solution, the cleaning efficiency is improved.

In collecting turbidity components including protozoa deposited on the surface of the porous hollow fiber membrane, the porous hollow fiber membrane is cut from the hollow fiber membrane cartridge, and only the cut porous hollow fiber membrane is washed. It is preferable to induce the turbidity component on the membrane surface into the washing solution by washing in the inside, since the distance between the hollow fiber membranes is increased and the washing efficiency is improved.

When the turbidity component including protozoa deposited on the surface of the porous hollow fiber membrane is collected, the turbidity component on the membrane surface is passed through the washing solution by passing the washing solution in the reverse direction of the sample filtration. And the turbidity component that has entered the micropores can also be recovered.

In recovering the turbid component including protozoa deposited on the surface of the porous hollow fiber membrane, the washing solution is circulated through the primary side of the porous hollow fiber membrane to induce the turbid component into the washing solution. When released, the impact on the protozoa is reduced by washing the membrane surface with a stream of water.

Preferably, when a surfactant is added to the washing solution, the recovery of the turbidity component is improved. More preferably, if an antifoaming agent is added to the cleaning liquid, it is possible to prevent a reduction in the recovery rate due to the generation of foam.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing an example of the hollow fiber membrane cartridge for capturing protozoa of the present invention. One end of a U-shaped porous hollow fiber membrane 11 having a maximum pore diameter of 2.0 μm or less is supported and fixed in a cap 16 with a hollow portion opened by a potting material 12. Is connected to a water outlet 13 for sending permeated water that has passed through the porous hollow fiber membrane 11 to the outside. The outer cylinder 17 is
A water supply port 14 for the sample water is provided below it, and is detachably engaged with the cap 16. Also, the cap 16
An O-ring 15 is disposed at an engagement portion between the outer cylinder 17 and the outer cylinder 17.

A sample water containing protozoa is passed through the hollow fiber membrane cartridge from the water supply port 14 to the outer cylinder 17, and the sample water is filtered by suction filtration or pressure filtration. When the filtration method is suction filtration, the clogging of the porous hollow fiber membrane does not easily occur when the protozoa is recovered using river water having high turbidity as a test water, which is preferable.

Since the protozoa are concentrated on the primary side of the porous hollow fiber membrane, the protozoa can be filtered to a predetermined amount and then recovered as concentrated water, or the whole sample can be filtered and the porous membrane can be filtered. The turbidity components including protozoa deposited on the surface are collected. In addition, even when the protozoa is collected as concentrated water, it is preferable to further collect the turbidity components including the protozoa deposited on the membrane surface after the filtration, from the viewpoint of improving the collection efficiency of the protozoa.

[0027] Filtration of a sample containing protozoa using a porous hollow fiber membrane having a maximum pore diameter of 2.0 µm or less can increase the membrane area as compared with a conventional recovery method. In addition, the volumetric efficiency can be improved, and a large amount of sample water can be filtered in a short time and with high recovery efficiency.
At this time, it is preferable that the sample water be filtered at a transmembrane pressure difference of ² kg / cm ² or less, since clogging of the surface of the porous hollow fiber membrane does not easily occur.

When the sample water is passed through the hollow fiber membrane cartridge while the hollow fiber membrane cartridge is vibrated with a test tube stirrer or the like, the turbidity component trapped on the membrane surface is shaken off. This is preferable because it is difficult to adhere to the film surface.

When the sample water is passed through the hollow fiber membrane cartridge, the sample water is passed for a certain time (or a fixed amount), and then intermittent water flow is stopped for a certain time. It is preferable because the temperature component hardly adheres.

When recovering the turbidity component containing protozoa deposited on the surface of the hollow fiber membrane, the porous hollow fiber membrane is immersed in a washing solution and washed with a fibrous material.
The turbidity component that has entered between the membranes can be induced, which is preferable. Alternatively, immerse the porous hollow fiber membrane in the cleaning solution,
When the turbidity component is induced in the cleaning liquid by vibrating the porous hollow fiber membrane, physical shock due to utensils and the like used for fir washing is reduced, and the risk of destruction of the parasite is reduced.

More preferably, when the porous hollow fiber membrane is immersed in an ultrasonic cleaner and cleaned by ultrasonic cleaning, fine vibrations are given to the microporous hollow fiber membrane, and the cleaning efficiency is improved. Although it is preferable, when there is a possibility that the turbidity component is destroyed by ultrasonic waves, it is preferable to apply vibration with a vibration stirrer such as a shaker.

When the turbidity component on the surface of the porous hollow fiber membrane is recovered by these methods, the hollow fiber membrane is cut from the hollow fiber membrane cartridge, and only the hollow fiber membrane is washed in a washing solution. This is preferable because the interval between the yarn membranes is increased and the washing efficiency is improved.

When the turbidity component deposited on the surface of the porous hollow fiber membrane is recovered, the washing solution is passed through in the opposite direction to the filtration of the sample water to remove the turbidity component on the membrane surface. You may be invited. By using such a method, the turbidity component that has entered the micropores can also be recovered. Alternatively, the turbidity component on the membrane surface may be induced by circulating the washing liquid on the primary side of the hollow fiber membrane. When such a method is used, the membrane surface is washed with a water flow, and the impact on the protozoa is reduced.

It is preferable to add a surfactant to the cleaning solution used for cleaning the membrane surface, because the efficiency of recovering the turbidity component is improved. In addition, when an antifoaming agent is added to the cleaning solution, the number of protozoa attached to the outer cylinder wall surface due to the generation of bubbles is reduced, and the recovery rate is preferably increased. The obtained recovered liquid is transferred to a centrifuge tube, and the protozoa are separated into solid and liquid by a centrifuge.

FIG. 2 is a sectional view schematically showing another embodiment of the hollow fiber membrane cartridge for capturing protozoa of the present invention. The cap 21 has a water supply port 22 and a water outlet 23 above it. The water outlet 23 communicates with a holder 26, in which a hollow portion of a plurality of U-shaped porous hollow fiber membranes 24 is supported and fixed so as to maintain an open state. 25 are provided. Also,
The outer cylinder 27 containing the concentrated water is detachably engaged with the cap 21. If a tube that can be commonly used as a centrifuge centrifuge is used as the outer cylinder 27, centrifugation can be performed by directly inserting the centrifuge into the rotor of the centrifuge, so that the operation time can be reduced. .

FIG. 3 is a sectional view schematically showing another embodiment of the hollow fiber membrane cartridge for capturing protozoa of the present invention. A water outlet 32 for taking out permeated water that has passed through the porous hollow fiber membrane is provided on the side of the outer cylinder 33, and a plurality of porous hollow fiber membranes 34 are opened inside at both ends thereof. It is supported and fixed by the potting material 35 while keeping it.

One open end of the hollow fiber membrane is
Is connected to a water supply port 36 for passing a test water through the hollow portion, and the other end thereof is connected to an inside of a water collecting cylinder 37 for storing concentrated water. The outer cylinder and the water collecting cylinder are connected by engaging a cap 38 attached below the outer cylinder with the water collecting cylinder.

The cap 38 is provided with a hydrophobic porous material 39 for communicating the space inside the water collecting tube 37 with the space outside the water collecting tube 37. The hollow fiber membrane cartridge 3 that opens into the space inside the outer cylinder 37 is made of the hydrophobic porous material 39.
It is preferable to attach the opening above the opening end face of the first opening.

FIG. 4 is a cross-sectional view schematically showing another embodiment of the hollow fiber membrane cartridge for capturing a parasite according to the present invention. The outer cylinder 41 is a container having a water supply port 42 and a circulating water outlet 43, and a potting material 45 is provided in the container so that the hollow portions of the plurality of porous hollow fiber membranes 44 bent in a U-shape maintain an open state. And a hollow fiber membrane supported and fixed by the above. An outlet end face of the opening of the potting portion 45 communicates with an outlet 46 of permeated water that has passed through the porous hollow fiber membrane.

By connecting a liquid feed pump to the water supply port 42 and passing the test water under pressure, permeated water is taken out from the water outlet 46 and concentrated water is sent from the circulating water outlet to the outside of the cartridge.

In the hollow fiber cartridge of this embodiment, the sample water is subjected to cross-flow filtration by the hollow fiber membrane cartridge. Therefore, the sample water is circulated in the liquid phase on the primary side of the hollow fiber membrane in the cartridge, and the surface of the hollow fiber membrane is always kept. Since the water is flowing, the turbidity component does not accumulate and adhere to the surface of the hollow fiber membrane, and the step of recovering the turbidity component on the membrane surface can be omitted. Alternatively, the same effect can be obtained even when the liquid phase is stirred on the primary side of the hollow fiber membrane.

FIG. 5 is a cross-sectional view schematically showing another embodiment of the hollow fiber membrane cartridge for capturing protozoa according to the present invention. The outer cylinder 51 is a container having a water outlet 52 for permeated water that has passed through the porous hollow fiber membrane, and a potting material is provided in the container so that both ends of the hollow portions of the plurality of porous hollow fiber membranes 53 are kept open. It is supported and fixed at 54. One end of the opening of the hollow fiber membrane is connected to a water supply port 55 for supplying water to the hollow part of the hollow fiber membrane, and the other end is connected to a circulating water outlet 56. A part of the test water passed through the water supply port is taken out from the water outlet as permeated water, and the concentrated water is sent from the circulating water outlet to the outside of the cartridge.

[0043]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments. In this example, chlorella, which is a microorganism having a size (4 to 10 μm) having substantially the same diameter as the oocyst, was used, and a solution obtained by dissolving chlorella in Nagoya city water so as to have a chlorella concentration of 100 / L was used as a sample. Was.

The hollow fiber membrane cartridge for capturing protozoa used in the examples includes a porous hollow fiber membrane made of polyethylene manufactured by Mitsubishi Rayon Co., Ltd. (maximum pore diameter: 1.0 μm, inner diameter: 270 μm, outer diameter: 380 μm). ), The hollow fiber membrane cartridge was designed such that the effective fiber length of the hollow fiber membrane was 80 mm, the filling rate of the hollow fiber membrane was 40%, and the membrane area was 1650 cm ² (hollow fiber membrane outer diameter base).

<Example 1> An aspirator was connected to the water outlet 13 of the hollow fiber membrane cartridge for trapping protozoa shown in FIG. 1, and 40 L of test water was passed through the water supply port 14 to the outer cylinder 17. Suction filtration was performed at 0.7 kg / cm ² until water remaining in the outer cylinder disappeared. Next, the cap was removed from the outer cylinder, and the hollow fiber membrane portion was washed with 200 ml of a washing solution to obtain 200 ml of a recovered solution. The concentration ratio of the obtained recovered liquid was 200 times, and the time required to obtain the recovered liquid was about 60 minutes.

The washing solution was 0.1% each of sodium dodecyl sulfate (SDS) as a surfactant and Tween 80 (manufactured by Nagoya Katayama Chemical Co., Ltd.), and Sig as a defoaming agent.
A preparation solution containing 0.01% maAntifoam A (manufactured by Sigma Chemical Company) was used.

The obtained recovered solution was distributed into a 50 ml centrifuge tube, set in a centrifuge (KR-20,000S manufactured by Kubota), and centrifuged at 3000 rpm for 10 minutes.
After the supernatant was removed by suction, the PBS solution was added and resuspended, and centrifugation was performed in the same manner.
The PBS solution was added and resuspended to obtain a PBS sample.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was diluted with an omnipore membrane (Pill made by Millipore).
When filtered through a TFE membrane (pore size: 1 μm, diameter: 47 mm) and chlorella trapped on the membrane surface was counted,
292 were confirmed.

From this, the recovery rate of Chlorella was about 73%. Further, 1 L of the filtrate filtered through the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed. As a result, no chlorella was confirmed. In this example, the time required from the start of water flow to the time when the PBS sample was obtained was about 90 minutes.

<Embodiment 2> The aspirator is connected to the water outlet 23 of the hollow fiber membrane cartridge for trapping protozoa, in which the outer cylinder 27 shown in FIG. 40 L of test water was passed, and suction filtration was performed at a transmembrane pressure difference of 0.7 kg / cm ² .
Next, the outer cylinder of the hollow fiber membrane cartridge was removed, and the concentrated water in the outer cylinder was recovered. At this time, the recovered liquid volume was 35 ml.

Next, another outer cylinder was set on the cap, and 35 ml of washing water was injected from a water outlet of the cap with a 50 ml syringe to perform back-flow washing, whereby the surface of the hollow fiber membrane was turbid. The cleaning solution that has induced the components
Housed in an outer cylinder.

This back water washing was performed three times in total, and 140 ml of a recovered liquid was obtained in combination with the above-mentioned concentrated water. The concentration ratio of the obtained recovered solution was 286 times, and the time required to obtain the recovered solution was about 60 minutes. The washing solution contains sodium dodecyl sulfate (SDS) as a surfactant and Tw
een80 0.1% each, Sigma as defoamer
A preparation solution containing 0.01% Antifoam A was used.

The collected solution contained in the four outer cylinders was set in a centrifuge as it was, centrifuged at 3000 rpm for 10 minutes, and the supernatant was removed by suction. After performing centrifugal sedimentation and removing the supernatant liquid by suction, a PBS solution was added again to resuspend, thereby obtaining a PBS sample.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was filtered through an omnipore membrane. Chlorella captured on the membrane surface was counted, and 312 cells were confirmed. Thus, the recovery rate of Chlorella was about 78%. Further, 1 L of the filtrate filtered through the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed. Chlorella was not confirmed. The time required from the start of water passage to obtaining the PBS sample was about 90 minutes.

<Embodiment 3> A liquid feeding pump is connected to a water supply port 36 of a hollow fiber membrane cartridge for capturing parasites, which is provided with a water collecting tube 37 (capacity 50 ml) shown in FIG. Further, the hollow fiber membrane cartridge was set on a vibration stirrer (trade name: Vortex), and while the hollow fiber membrane cartridge was vibrated, 40 L of test water was supplied under pressure and filtered. At this time, the transmembrane pressure was 1.0 kg / cm ² .

Next, the water collecting cylinder in which the concentrated water was stored was removed. At this time, the amount of the recovered liquid was 50 ml. Then
A new water collecting cylinder was set in the hollow fiber membrane cartridge, and 50 ml of washing water was injected from a water supply port using a 50 ml syringe to wash the hollow portion of the hollow fiber membrane, and contained a turbidity component on the membrane surface. The washing liquid was stored in a water collecting cylinder.

This washing operation was performed three times in total, and 200 ml of a recovered liquid was obtained by combining the concentrated water. The concentration ratio of the obtained recovered liquid was 200 times, and the time required to obtain the recovered liquid was about 60 minutes. The washing solution contains sodium dodecyl sulfate (SDS) as a surfactant and Tween80.
0.1% each, Sigma Anti as defoamer
A preparation solution containing 0.01% of foam A was used.

The total of four collected liquids collected in the water collecting tube were set in a centrifuge as they were, centrifuged at 3000 rpm for 10 minutes, and the supernatant was removed by suction. Then, the mixture was centrifuged and precipitated, and the supernatant was removed by suction. Then, a PBS solution was added again to resuspend the suspension to obtain a PBS sample.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was filtered through an omnipore membrane, and chlorella captured on the membrane surface was counted. Thus, the recovery of Chlorella was about 84%. When 1 L of the filtrate from the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed, no chlorella was confirmed. The time required from the start of water passage to obtaining the PBS sample was about 90 minutes.

<Embodiment 4> A liquid feed pump was connected to the water supply port 42 of the hollow fiber membrane cartridge for capturing protozoa shown in FIG. 4, and 40 L of test water was pressurized and passed therethrough. c
Filtration was performed at m ² . At this time, the sample water is supplied to the hollow fiber membrane cartridge at a flow rate of 10 L / min, the flow rate of the permeated water from the water outlet 46 is 5 L / min, and the circulation flow rate of the test water flowing out from the circulating water outlet is 5 L / min. Cross-flow filtration was performed as follows. After performing cross-flow filtration until the amount of the test water reached 400 ml, concentrated water was recovered. The concentration ratio of the obtained recovered liquid was 100 times, and the time required to obtain the recovered liquid was about 30 minutes.

The obtained recovered solution was distributed to a 50 ml centrifuge tube, set in a centrifuge, centrifuged at 3000 rpm for 10 minutes, and the supernatant was removed by suction. Then, the mixture was centrifuged and precipitated, and the supernatant was removed by suction. Then, a PBS solution was added again to resuspend the suspension to obtain a PBS sample.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was filtered through an omnipore membrane, and chlorella captured on the membrane surface was counted. As a result, 308 cells were confirmed. Thus, the recovery rate of Chlorella was about 77%. When 1 L of the filtrate from the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed, no chlorella was confirmed. The time required from the start of water passage to obtaining the PBS sample was about 60 minutes.

Example 5 A liquid feed pump was connected to the water supply port 55 of the hollow fiber membrane cartridge for capturing protozoa shown in FIG. 5, and 40 L of test water was subjected to pressure filtration at a transmembrane pressure difference of 1.0 kg / cm ^2. did. At this time, the hollow fiber membrane cartridge has 10 L / m
The sample water was supplied at a flow rate of “in”, and the cross flow filtration was performed such that the flow rate of the permeated water from the water outlet 52 was 5 L / min and the flow rate of the circulating water from the circulating water outlet was 5 L / min.

The cross-flow filtration was performed until the amount of the test water reached 400 ml, and the concentrated water was recovered. The concentration ratio of the obtained recovered liquid was 100 times, and the time required to obtain the recovered liquid was about 30 minutes. The obtained recovered liquid is 50 m
l Dispense into a centrifuge tube, set in a centrifuge, and
After performing centrifugal sedimentation at pm × 10 minutes, removing the supernatant liquid by suction, adding a PBS liquid and resuspending the mixture, similarly performing centrifugal sedimentation, removing the supernatant liquid by suction and adding a PBS liquid again to resuspend. P
A BS sample was used.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was filtered through an omnipore membrane, and chlorella captured on the membrane surface was counted. Thus, the recovery of Chlorella was about 88%. When 1 L of the filtrate from the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed, no chlorella was confirmed. The time required from the start of water flow to the time when the PBS sample was obtained was about 60 minutes.

<Example 6> An aspirator was connected to the water outlet of the hollow fiber membrane cartridge for capturing protozoa similar to that used in Example 1, and 40 L of sample water was subjected to suction filtration until no water remained in the outer cylinder. Water was supplied intermittently at intervals of 30 seconds and 30 seconds after stopping. The transmembrane pressure during suction filtration is 0.7 kg / c.
m ² .

Next, the outer cylinder and the cap of the hollow fiber membrane cartridge are divided, the hollow fiber membrane part and the potting part of the cap are cut off, and the hollow fiber membrane part is washed in an ultrasonic cleaner containing 200 ml of a washing liquid. , 200 ml of a recovered liquid were obtained. The concentration ratio of the obtained recovered liquid was 200 times, and the time required to obtain the recovered liquid was about 60 minutes.

The washing solution was prepared by adding 0.1% each of sodium dodecyl sulfate (SDS) and Tween 80 as a surfactant.
%, Sigma Antifoam A as antifoaming agent
A preparation solution containing 0.01% was used.

The obtained recovered solution was distributed to a 50 ml centrifuge tube, set in a centrifuge, centrifuged at 3000 rpm for 10 minutes, and the supernatant was removed by suction. Similarly, centrifugal sedimentation was performed, and the supernatant was removed by suction. Then, a PBS solution was added again to resuspend, thereby obtaining a PBS sample.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was filtered through an omnipore membrane, and chlorella captured on the membrane surface was counted. As a result, 368 were confirmed. Thus, the recovery rate of Chlorella was about 92%. 1 L of the filtrate from the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed. Chlorella was not confirmed. The time required from the start of water passage to obtaining the PBS sample was about 90 minutes.

<Example 7> An aspirator was connected to the water supply port of the hollow fiber membrane cartridge for capturing parasites having the same specifications as those used in Example 1, and 40 L of the test water was used until no water remained in the outer cylinder 17. Suction filtration was performed. At this time, the transmembrane pressure was 0.1.
It was 7 kg / cm ² .

Next, the cap and the outer cylinder of the hollow fiber membrane cartridge were divided, and the porous hollow fiber membrane and the potting portion of the cap were cut off. Thereafter, the cut porous hollow fiber membrane was washed with a vibration stirrer containing 200 ml of a washing solution,
200 ml of recovered liquid was obtained. The time required to obtain the recovered liquid was about 60 minutes.

The concentration of the obtained recovered liquid was 200 times. The washing liquid was 0.1% each of sodium dodecyl sulfate (SDS) and Tween 80 as surfactants, and Sigma Antifoam A 0.0 as antifoaming agent.
A preparation solution containing 1% was used.

The obtained recovered solution was distributed to a 50 ml centrifuge tube, set in a centrifuge, centrifuged at 3000 rpm for 10 minutes, and the supernatant was removed by suction. Similarly, centrifugal sedimentation was performed, and the supernatant was removed by suction. Then, a PBS solution was added again to resuspend, thereby obtaining a PBS sample.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was filtered through an omnipore membrane, and chlorella captured on the membrane surface was counted. As a result, 348 cells could be confirmed. Thus, the recovery rate of Chlorella was about 87%. 1 L of the filtrate from the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed. Chlorella was not confirmed. The time required from the start of water flow to the time when the PBS sample was obtained was about 90 minutes.

<Comparative Example 1>"Temporary Guideline for Cryptosporidium in Water Supply-Appendix 3 Provisional test for detection of Cryptosporidium oocysts in tap water" published by the Ministry of Health on September 30, 1996. The following experiment was conducted with reference to the oocyst analysis method by "Method".

A cellulose acetate membrane filter manufactured by Toyo Roshi Kaisha Co., Ltd. (size: 47 mm, pore size: 0.8 μm)
Was set in a filter holder, and 40 L of test water prepared with 100 chlorella / L was suction-filtered with an aspirator. One membrane filter can filter 7 to 8 L of test water, and six membrane filters were used to pass 40 L of water. When the obtained six membrane filters were dissolved in 20 ml of acetone, they were completely dissolved.
20 ml of acetone was used as a recovery liquid. The concentration ratio of the obtained recovered liquid was 2000 times, and the time required to obtain the recovered liquid was about 180 minutes.

The obtained recovered solution was set in a centrifuge,
The suspension was centrifuged at 3000 rpm for 10 minutes, the supernatant was removed by suction, acetone was added again, and the suspension was resuspended to perform centrifugal precipitation. After performing a centrifugation operation with acetone three times, a purified solution (a solution obtained by filtering double-distilled water through a filter having a pore size of 0.45 μm or less) was added to the obtained sediment, followed by resuspension and centrifugation similarly. After the supernatant was removed by suction, a PBS solution was added thereto to resuspend the suspension, and the mixture was centrifuged in the same manner. After the supernatant was removed by suction, the PBS solution was added again and resuspended to obtain a PBS sample.

The obtained PBS sample was diluted to 1 L, and 100 ml of the diluted solution was filtered through an omnipore membrane, and chlorella captured on the membrane surface was counted. As a result, 252 cells were confirmed. Thus, the recovery rate of Chlorella was about 63%. 1 L of the filtrate is filtered through an omnipore membrane,
Chlorella was not observed when the film surface was observed. The number of times of centrifugal sedimentation was 5, and the time required from the start of water passage to obtaining the PBS sample was about 300 minutes. At this time, the time required to filter 40 L was about 3 hours. During this time, the experimenter could not leave the place because the filter had to be replaced and the sample water had to be supplied to the filter holder.

<Embodiment 8> A liquid feeding pump was connected to the water supply port of a hollow fiber membrane cartridge having the same specifications as the hollow fiber membrane cartridge for capturing protozoa used in Example 5, and 800 L of test water was applied to the membrane with a transmembrane pressure of 1. Pressure filtration was performed at 0.0 kg / cm ² . At this time, the flow was supplied to the hollow fiber membrane cartridge at a flow rate of 10 L / min, and the cross flow filtration was performed at a flow rate of 5 L / min from the permeated water outlet and a flow rate of 5 L / min from the circulating water outlet.

Cross-flow filtration was carried out until the amount of the test water reached 400 ml, and concentrated water was recovered. The concentration ratio of the obtained recovered liquid was 2000 times, and the time required to obtain the recovered liquid was about 180 minutes.

The obtained recovered solution was distributed to a 50 ml centrifuge tube, set in a centrifuge, centrifuged at 3000 rpm for 10 minutes, and the supernatant was removed by suction. Similarly, centrifugal sedimentation was performed, and the supernatant was removed by suction. Then, a PBS solution was added again to resuspend, thereby obtaining a PBS sample.

The obtained PBS sample was diluted to 20 L, and 100 ml of the diluted solution was filtered through an omnipore membrane, and the number of chlorella captured on the membrane surface was counted. As a result, 312 chlorella were confirmed. Thus, the recovery rate of Chlorella was about 78%. 1 L of the filtrate from the hollow fiber membrane cartridge was filtered through an omnipore membrane, and the membrane surface was observed. Chlorella was not confirmed. The time required from the start of water flow to obtaining the PBS sample was about 220 minutes.

In this example, the concentration ratio was compared with that of Comparative Example 1.
Although the experiment was performed at 2000 times as high as that of Example 1, the protozoa could be captured and recovered at a higher recovery rate than Comparative Example 1. In addition, it was possible to treat the sample water 20 times in approximately the same time as Comparative Example 1.

[0085]

According to the method for capturing and recovering protozoa of the present invention,
Upon capturing and recovering the protozoa contained in the test water, by passing the test water through a hollow fiber membrane cartridge provided with a porous hollow fiber membrane having fine pores having a maximum pore diameter of 2.0 μm or less, and filtering the water, After concentrating the test water on the primary side of the porous hollow fiber membrane, the concentrated water containing the protozoa and / or the turbidity component containing the protozoa deposited on the surface of the porous hollow fiber membrane are recovered. Compared with the method, the membrane area can be increased, the volumetric efficiency can be improved, and the protozoa can be captured and recovered in a short time and with high recovery efficiency.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a hollow fiber membrane cartridge for capturing protozoa of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the hollow fiber membrane cartridge for capturing protozoa of the present invention.

FIG. 3 is a sectional view showing another embodiment of the hollow fiber membrane cartridge for capturing protozoa of the present invention.

FIG. 4 is a sectional view showing another embodiment of the hollow fiber membrane cartridge for capturing protozoa of the present invention.

FIG. 5 is a cross-sectional view showing another embodiment of the hollow fiber membrane cartridge for capturing protozoa of the present invention.

[Explanation of symbols]

 17, 27, 34, 41, 51 Outer cylinder 11, 24, 34, 44, 53 Porous hollow fiber membrane 12, 25, 35, 45, 54 Potting material 14, 22, 36, 42, 55 Water supply port 13, 23 , 32, 46, 52 Outlet 16, 21, 38 Cap 15 O-ring 26 Holder 37 Water collecting cylinder 39 Hydrophobic porous material 43, 56 Circulating water outlet

────────────────────────────────────────────────── ─── Continuing on the front page (51) Int.Cl. ⁶ Identification symbol FI B01D 65/06 B01D 65/06 (72) Inventor Masanao Koho 4-60 Sunadabashi, Higashi-ku, Nagoya-shi, Aichi Mitsubishi Rayon Co., Ltd. Inside the Product Development Laboratory (72) Inventor Hiroshi Tasaka 4-1-1-60 Sunadabashi, Higashi-ku, Nagoya City, Aichi Prefecture Mitsubishi Rayon Co., Ltd. Product Development Laboratory

Claims (16)

[Claims] 1. A porous hollow fiber membrane having two ends open and potted inside an outer cylinder, wherein the outer cylinder has a water supply port for supplying sample water to the outer surface of the porous hollow fiber membrane; A hollow fiber membrane cartridge for capturing protozoa, wherein a water outlet for extracting permeated water is provided so as to communicate with an open end of the hollow fiber membrane. 2. The porous hollow fiber membrane has two ends separately open and potted inside the outer cylinder, and the outer cylinder has a water supply port for supplying test water to one open end of the porous hollow fiber membrane. An outlet for communicating with the outer surface side of the porous hollow fiber membrane to take out permeated water, and extracting concentrated water from another open end of the porous hollow fiber membrane; Thread membrane cartridge. 3. When capturing and recovering protozoa contained in the sample water, the sample water is passed through a hollow fiber membrane cartridge provided with a porous hollow fiber membrane having fine pores having a maximum pore diameter of 2.0 μm or less. After the sample is concentrated on the primary side of the porous hollow fiber membrane by filtration, concentrated water containing the protozoa and / or turbidity components containing the protozoa deposited on the surface of the porous hollow fiber membrane are recovered. A method for capturing and recovering protozoa. 4. The method for capturing and recovering protozoa according to claim 3, wherein the sample water is passed while the hollow fiber membrane cartridge is vibrated and filtered. 5. The method for capturing and recovering protozoa according to claim 3, wherein a test water is intermittently passed through the hollow fiber membrane cartridge. 6. The method for capturing and recovering protozoa according to claim 3, wherein a test water is passed through while stirring or circulating the liquid phase in a space on the primary side in the hollow fiber membrane cartridge, and filtration is performed. 7. The method for capturing and recovering parasites according to claim 3, wherein the sample water is filtered by sucking the secondary side of the porous hollow fiber membrane. 8. The method for capturing and recovering protozoa according to claim 3, wherein the filtration of the sample water is performed at a transmembrane pressure difference of ² kg / cm ² or less. 9. A turbidity component containing protozoa deposited on the surface of a porous hollow fiber membrane is recovered by immersing the porous hollow fiber membrane in a cleaning solution and rinsing to remove the turbidity component on the membrane surface. The method for capturing and recovering protozoa according to claim 3, wherein the protozoa are induced into the inside. 10. A method for recovering turbidity components including protozoa deposited on the surface of a porous hollow fiber membrane, by immersing the porous hollow fiber membrane in a cleaning solution in a cleaning solution tank and vibrating the porous hollow fiber membrane. 4. The method for capturing and recovering protozoa according to claim 3, wherein the turbid component on the membrane surface is induced into the washing solution by the method. 11. When recovering a turbid component containing protozoa deposited on the surface of a porous hollow fiber membrane, the porous hollow fiber membrane is immersed in a cleaning solution in an ultrasonic cleaner, and the surface of the membrane is cleaned by ultrasonic cleaning. The method for capturing and recovering protozoa according to claim 10, wherein the turbidity component is induced into the washing solution. 12. When recovering a turbid component containing protozoa deposited on the surface of the porous hollow fiber membrane, the porous hollow fiber membrane is cut from the hollow fiber membrane cartridge, and only the cut porous hollow fiber membrane is washed. The method for capturing and recovering protozoa according to claim 3, wherein the turbidity component on the membrane surface is induced into the cleaning solution by washing in the inside. 13. When the turbidity component containing protozoa deposited on the surface of the porous hollow fiber membrane is recovered, the turbidity component on the membrane surface is passed through the washing solution by passing the washing solution in the reverse direction of the sample filtration. The method for capturing and recovering protozoa according to claim 3, wherein the parasite is induced. 14. When the turbidity component containing protozoa deposited on the surface of the porous hollow fiber membrane is recovered, the turbidity component is introduced into the cleaning solution by circulating the washing solution through the primary side of the porous hollow fiber membrane. The method for capturing and recovering protozoa according to claim 3, wherein the protozoa are collected. 15. The method for capturing and recovering protozoa according to any one of claims 12 to 14, wherein a surfactant is added to the washing solution. 16. The method for capturing and recovering protozoa according to claim 15, wherein an antifoaming agent is added to the cleaning liquid.