JP2005143379A - Method and apparatus for recovering microorganism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for recovering microorganisms, by which a large amount of microorganisms are treated in high efficiency. <P>SOLUTION: In recovering object microorganisms in water, the object microorganisms in water are separated and concentrated by using a hollow fiber membrane of cross flow filtration type. The object microorganisms separated and concentrated by the hollow fiber membrane are subjected to reversal washing with a solution in an amount smaller than water before the separation and concentration, released from the hollow fiber membrane, further separated, concentrated and immobilized by using a membrane filter from the solution having the object microorganisms concentrated by the reversal washing after the reversal washing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for collecting microorganisms in water and an apparatus for carrying out this method.

In general, a separation medium such as a hollow fiber membrane or a membrane filter is used for collecting microorganisms (see, for example, Patent Document 1). As a recovery operation, tens of liters (liter) is collected from a river or lake as sample test water, and suction or pressure filtration separation is performed using the above-mentioned separation medium, and then a trapping substance is dissolved in the medium. And the microorganisms were separated, concentrated and recovered by a method such as centrifugation. In particular, this method has been applied to chlorine-resistant pathogenic microorganisms including Cryptosporidium.
Japanese Patent Laid-Open No. 11-193

  However, when the number of microorganisms to be collected is very small, it has been pointed out that the collection rate is low. For example, in the recovery of chlorinated pathogenic microorganisms, particularly Cryptosporidium, because the number of solids is less than that of general microorganisms, it is difficult to accurately determine the presence or absence of individuals when collecting water of about several tens of liters, Since the water is collected in a batch mode, it is greatly affected by the water conditions (water flow, turbidity, etc.) at the time of sampling. Therefore, there is a need for mass processing and continuous processing of sample water.

  Further, as described above, the collection method using a membrane filter is generally used for the collection of microorganisms. For example, Cryptosporidium is also used in the provisional detection test method established by the former Ministry of Health and Welfare. However, when performing filtration separation with a membrane filter, even with a sample water of several liters, the filtration efficiency gradually decreases with one filter. Therefore, it is necessary to perform filtration separation by replacing or installing several series of filters. The replacement work becomes complicated. This also contributed to a reduction in the recovery rate.

  The present invention has been made in order to solve the above-described problems, and it is an object of the present invention to provide a microorganism recovery method and recovery apparatus capable of high-efficiency and large-scale processing.

The invention according to claim 1
In a microorganism recovery method for recovering target microorganisms in water,
Separating and concentrating target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
A step of separating and concentrating the target microorganism separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a smaller amount of solution than water before separation and concentration;
Further separating, concentrating and immobilizing the target microorganism using a membrane filter from the backwash solution in which the target microorganism is concentrated by backwashing;
Are sequentially executed.

The invention according to claim 2
In a microorganism recovery method for recovering target microorganisms in water,
Separating and concentrating target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
A step of separating and concentrating the target microorganism separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a smaller amount of solution than water before separation and concentration;
Further separating and concentrating the target microorganism using a membrane filter from the backwash solution in which the target microorganism is concentrated by backwashing;
Separating the target microorganisms separated and concentrated by the membrane filter with a smaller amount of solution than the backwash solution;
Are sequentially executed.

  The invention according to claim 3 is characterized in that, in the microorganism recovery method according to claim 1 or 2, the target microorganism is a chlorine-resistant pathogenic microorganism.

The invention according to claim 4
In a microorganism recovery device that recovers target microorganisms in water,
Means for separating and concentrating target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
Means for separating and concentrating the target microorganism separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a solution in a smaller amount than the water before separation and concentration;
Means for further separating, concentrating and immobilizing the target microorganism using a membrane filter from the backwash solution in which the target microorganism is concentrated by backwashing;
It is provided with.

The invention according to claim 5
In a microorganism recovery device that recovers target microorganisms in water,
Means for separating and concentrating target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
Means for separating and concentrating the target microorganism separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a solution in a smaller amount than the water before separation and concentration;
Means for further separating and concentrating the target microorganism using a membrane filter from the backwash solution in which the target microorganism is concentrated by backwashing;
Means for separating the target microorganisms separated and concentrated by the membrane filter with a smaller amount of solution than the backwash solution;
It is provided with.

  The invention according to claim 6 is the microorganism collection apparatus according to claim 4 or 5, wherein the microfiber is separated by means for separating and concentrating target microorganisms in water using a cross-flow filtration type hollow fiber membrane, and the hollow fiber membrane. And a means for backwashing the concentrated target microorganism with a smaller amount of solution than water before separation and concentration, and separating it from the hollow fiber membrane.

  The invention according to claim 7 is the microorganism collection apparatus according to any one of claims 4 to 6, wherein the target microorganism is a chlorine-resistant pathogenic microorganism.

  The invention according to claim 8 is the microorganism collecting apparatus according to any one of claims 4 to 7, wherein a solution containing a surfactant is added to the sample water to form a cross-flow filtration type hollow fiber membrane. It is characterized by separating and concentrating target microorganisms in water using

  The invention according to claim 9 is the microorganism collection apparatus according to any one of claims 4 to 7, wherein a solution containing a surfactant is added to the backwash solution of the hollow fiber membrane, and the hollow fiber membrane is added. The target microorganisms separated and concentrated by the above step are back-washed with a solution having a smaller amount than water and peeled off from the hollow fiber membrane.

  The invention according to claim 10 is the microorganism collection apparatus according to any one of claims 4 to 9, further comprising means for physically accelerating the peeling operation of the target microorganism from the hollow fiber membrane. And

  According to the above configuration, the present invention enables high-efficiency and large-scale treatment of target microorganisms present in water.

  Hereinafter, the present invention will be described in detail based on preferred embodiments shown in the drawings. FIG. 1 is a system diagram showing a configuration of a first embodiment of a microorganism recovery apparatus for performing a microorganism recovery method according to the present invention.

In FIG. 1, a sampling water introduction path of the hollow fiber membrane separation unit 13 is provided with a water sampling valve V1, a sample water introduction tank 11, an introduction pump 12, an introduction part valve V2, and a unit inlet valve V3. The drainage path of the hollow fiber membrane separation unit 13 has two channels, a circulating water channel that flows through the same hollow fiber membrane surface where sample water flows in and is drained from the unit, and a sample that passes through the hollow fiber membrane Divided into permeate flow channels through which water is discharged. A unit outlet valve V4 and a circulating water passage valve V5 are provided in the circulating water passage. A unit permeated water valve V6 is provided in the permeated water side flow path. Further, a backwash pump 14 is provided in the backwash water introduction path of the hollow fiber membrane separation unit 13, and the introduction path is connected to the circulating water flow path and the permeated water flow path. A backwash valve V7 is provided in the circulating water passage. The sample water introduction path of the hollow fiber membrane separation unit 13 is branched between the introduction valve V2 and the unit inlet valve V3, and is connected to the intermediate concentrated sample water tank 15 via the intermediate concentrated sample water recovery valve V8. In the introduction path of the membrane filter unit 17, an intermediate concentrated sample water introduction valve V 9 and an introduction pump 16 are provided and connected to the membrane filter unit 17. A drainage valve V <b> 10 is provided in the drainage path of the membrane filter unit 17.

  The operation of the first embodiment configured as described above will be described below with reference to the conceptual diagram of the crossflow filtration method shown in FIG. The target microorganism is, for example, a chlorine-resistant pathogenic microorganism that forms spores. First, with the valves other than the water sampling valve V1 closed, the water sampling valve V1 is opened, and the sample water is introduced into the sample water introduction tank 11. In a state where a fixed amount is accumulated, the introduction valve V2, the unit inlet valve V3, the unit outlet valve V4, and the circulating water passage valve V5 are opened, and the introduction pump is driven. As a result, the sample water circulates through the hollow fiber membrane separation unit 13. And filtration of sample water is started by opening unit permeated water valve V6. Because of the cross-flow filtration method, part of the sample water is filtered and the remaining sample water is circulated. In this case, as shown in the conceptual diagram of the cross-flow filtration method in FIG. 2, a substance smaller than the pore diameter of the hollow fiber membrane 13a present in the sample water is transmitted along with the permeated water to the permeated water side flow path, and the hollow fiber membrane 13a. Substances larger than the pore diameter of the remaining water remain in the circulating water side flow path and are concentrated. The sample water is continuously supplied to the sample water introduction tank 11. By using the hollow fiber membrane separation unit 13 as the separation medium for the target microorganisms in the previous stage, it becomes possible to perform a large-scale treatment and a continuous treatment. For example, by setting the treatment amount of the sample water to 100 L or more, the collection amount of the collection target microorganisms Or the recovery probability is improved. Further, by adopting the cross flow filtration method as the filtration method of the hollow fiber membrane, it becomes possible to reduce the clogging of the membrane, extend the life of the membrane, and reduce the membrane regeneration process. Furthermore, although the upper limit of the processing amount is not particularly set, it is set according to the processing capacity (specification) of the hollow fiber membrane. Further, the processing speed is in accordance with the processing capacity (specification) of the hollow fiber membrane. In this way, after supplying a predetermined amount of sample water or after supplying sample water for a certain period of time, the sampling valve V1 is closed until the sample water supplied to the sample water introduction tank 11 reaches a constant water level. Continue filtration with hollow fiber membranes.

  Next, the introduction pump 12 is stopped, the unit permeated water valve V6 is closed, and the process proceeds to the hollow fiber membrane cleaning step. At this time, the introduction valve V2 and the circulating water flow path valve V5 are closed, the backwash valve V7 and the intermediate concentrated sample water recovery valve V8 are opened, and the backwash pump 14 is driven. As a result, the backwash water is supplied to the hollow fiber membrane separation unit 13, and the intermediate concentrated sample water tank 15 together with the backwash water supplied with a certain amount or for a predetermined time of the microorganisms including the microorganisms to be collected adhering to the hollow fiber membrane surface. To be drained.

  Next, by closing the unit inlet valve V3 and the unit outlet valve V4 and opening the inlet valve V2 and the circulating water passage valve V5, the backwash water is supplied to the circulating water passage, the sample water introduction tank 11 and the introduction pump 12. Then, the microorganisms including the microorganisms to be collected attached to the pipe and the like are drained into the intermediate concentrated sample water tank 15 together with the backwash water supplied for a certain amount or for a certain time. The amount of backwash water supplied is very small compared to the sample water. Further, the sample water that has passed through the hollow fiber membrane separation unit 13 may be used as the backwash water. The backwash pump 14 is stopped, all valves are closed, and the backwash process is completed.

  Next, by opening the intermediate concentrated sample water introduction valve V9 and the drainage valve V10 and driving the introduction pump 16, the intermediate concentrated sample water stored in the intermediate concentrated sample water tank 15 is guided to the membrane filter unit 17, Here, the microorganisms including the microorganisms to be collected are separated from the intermediate concentrated sample water, and the sample water that has permeated through the membrane filter unit 17 is drained through the drain valve V10. Thereby, the microorganisms to be collected are separated, concentrated and immobilized on the membrane filter.

  As described above, a process capable of high-efficiency and large-volume processing can be provided by combining the pre-treatment by the hollow fiber membrane separation unit 13 adopting the cross-flow filtration method and the post-treatment by the membrane filter unit 17. .

  Further, the type of chlorine-resistant pathogenic microorganism is not particularly limited. For example, Cryptosporidium, Giardia, cyclospolar, microspores and the like can be mentioned.

  Here, selection of the hole diameter in the hollow fiber membrane separation unit 13 and the membrane filter unit 17 will be described. For example, when a chlorine-resistant pathogenic microorganism, particularly Cryptosporidium, is used as a collection target microorganism, it is desirable to use a pore diameter of 1 μm or less. Many chlorine-resistant pathogenic microorganisms form spores and are included in a relatively large category of microorganisms compared to other microorganisms. Although the diameter of Cryptosporidium is generally reported to be 3 to 5 μm, the hole diameter of the hollow fiber membrane was set to 1 μm or less in consideration of the safety factor.

  However, this value is not absolute. By making the hole diameter as large as possible, the permeability of the membrane and long-term operability can be ensured. Furthermore, since minute impurities are removed from the target microorganism, the proportion of impurities in the separated component can be reduced. On the other hand, for membrane filters, it is desirable to make the diameter smaller than the set pore size of the hollow fiber membrane in the previous step, but by using a membrane with a pore size that is as large as possible, membrane permeability and long-term operability can be ensured. Furthermore, since minute impurities are removed from the target microorganism, the pore size is set to 1 μm or less because the ratio of impurities in the separated component can be reduced.

  FIG. 3 is a system diagram showing the configuration of the second embodiment of the microorganism collection apparatus according to the present invention. In the figure, the same elements as those of the first embodiment shown in FIG. In this embodiment, an elicited liquid injecting pump 18 and an elicited liquid injecting valve V11 are provided in the elicited liquid injecting path of the membrane filter unit 17, and a sample water draining valve is provided in the sample water draining path of the membrane filter unit 17. V12 is provided, and includes means for separating the collection target microorganisms separated and concentrated by the membrane filter from the membrane filter with a smaller amount of solution than the backwash solution. Other than this, the configuration is the same as that of the first embodiment shown in FIG.

  The operation of the second embodiment configured as described above will be described below in particular with respect to a portion having a configuration different from that in FIG. The intermediate concentrated sample water is guided to the membrane filter unit 17, where the microorganisms including the microorganisms to be collected are separated from the intermediate concentrated sample water, and the sample water that has permeated the membrane filter unit 17 is drained through the drain valve V10. Then, the concentrated sample water introduction valve V9 and the drainage valve V10 are closed, and the induced liquid injection pump 18 is driven in a state where the induced liquid injection valve V11 is opened, and a predetermined amount of the induced liquid is supplied to the membrane filter unit 17. Stay inside. Then, the sample water discharge valve V12 is opened after a predetermined time has elapsed. By this subsequent treatment, concentrated sample water containing the collection target microorganism is obtained. Here, the amount of the extract liquid from the membrane filter unit 17 is much smaller than that of the intermediate concentrated sample water.

  In the second embodiment, the attracting liquid is allowed to stay in the membrane filter unit 17 for a predetermined time. However, when the attracting liquid is injected, the sample water discharge valve V12 is kept open and the inducing liquid is injected. Depending on the concentration sample water can be collected.

  In the second embodiment, when the attracting liquid stays in the membrane filter unit 17 for a predetermined time, the membrane filter unit 17 is subjected to physical factors such as ultrasonic irradiation, mechanical vibration, and electrical vibration. It is also possible to promote separation and recovery of the trapped material from the membrane filter. As a result, microorganisms can be efficiently and quickly attracted to the liquid with a small volume. If necessary, repeat the above operation several times.

  FIG. 4 is a system diagram showing the configuration of the third embodiment of the microorganism collection apparatus according to the present invention. In the figure, the same elements as those of the first embodiment shown in FIG. This embodiment is provided with two or more sets of cross-flow filtration type hollow fiber membrane separation units (FIG. 4 shows the case of two sets), and all other parts are the same as those of the first embodiment shown in FIG. It is configured. Note that the second embodiment shown in FIG. 2 can be configured similarly. In this embodiment, between the hollow fiber membrane separation unit 13 and the membrane filter unit 17, the introduction pump 21, the introduction valve V21, the unit inlet valve V22, the hollow fiber membrane separation unit 22, the intermediate concentrated sample water tank 23, the unit An outlet valve V23, a circulating water flow path valve V24, and a backwash valve V26 are additionally provided, and all other configurations are the same as those of the first embodiment shown in FIG.

  The operation of the third embodiment configured as described above will be described particularly with respect to a portion having a configuration different from that in FIG. First, a predetermined amount of sample water is filtered by the hollow fiber membrane separation unit 13 provided at the front stage, and in the subsequent washing step, the surface of the hollow fiber membrane, the circulating water flow path, the sample water introduction tank 11, and the introduction pump 12. Microorganisms including the microorganisms to be collected adhering to the water are stored in the intermediate concentrated sample water tank 15 together with a certain amount of backwash water supplied for a certain period of time. Next, the intermediate concentrated sample water introduction valve V21, the unit inlet valve V22, the unit outlet valve V23, and the circulating water passage valve V24 are opened, and the introduction pump 21 is driven. As a result, the intermediate concentrated sample water is circulated through the second-stage hollow fiber membrane separation unit 22. And filtration of sample water is started by opening unit permeated water valve V25. Since this is a cross-flow filtration system, a part of the sample water is filtered and the remaining sample water is circulated. The sample water is continuously supplied to the intermediate concentrated sample water tank 15. The hollow fiber membrane separation unit 22 has a smaller filtration area and smaller unit volume than the preceding hollow fiber membrane separation unit 13. Although the front-stage hollow fiber membrane separation unit 13 needs to filter a large amount of sample water, the second-stage hollow fiber membrane separation unit 22 includes the front-stage hollow fiber membrane separation unit 13, the sample water introduction tank 11, and the introduction. It is sufficient if the capacity of the sample pump 12 and the circulating water path is sufficient to filter the sample water. Accordingly, the capacity of the introduction pump 21 only needs to be appropriate. The filtration treatment with the hollow fiber membrane is continued until the sample water in the intermediate concentrated sample water tank 15 runs out.

  Next, the introduction pump 21 is stopped, the unit permeated water valve V25 is closed, and the process proceeds to the hollow fiber membrane cleaning step. The introduction valve V21 and the circulating water flow path valve V24 are closed, the backwash valve V26 and the intermediate concentrated sample water recovery valve V27 are opened, and the backwash pump 14 is driven. At this time, the backwashing pump 14 used for washing the hollow fiber membrane separation unit in the previous stage is used as the backwashing pump. As a result, the backwash water is supplied to the hollow fiber membrane separation unit 22, and the microorganism containing the microorganisms to be collected attached to the surface of the hollow fiber membrane is supplied to the intermediate concentrated sample water tank 23 together with the backwash water supplied for a certain amount or for a certain time. Drained. Next, the unit inlet valve V22 and the unit outlet valve V23 are closed, and the introduction valve V21 and the circulating water passage valve V24 are opened, so that the backwash water is supplied to the circulating water passage, the intermediate concentrated sample water tank 15, and the introduction pump 21. Microorganisms including the microorganisms to be collected, which are supplied and attached to the piping or the like, are drained into the intermediate concentrated sample water tank 23 together with the backwash water supplied for a predetermined amount or for a predetermined time. The amount of backwash water supplied is very small compared to the intermediate concentrated sample water. Further, the sample water that has passed through the hollow fiber membrane separation unit 13 or the hollow fiber membrane separation unit 22 may be used as the backwash water. The backwash pump 14 is stopped, all valves are closed, and the backwash process is completed.

  Next, by opening the intermediate concentrated sample water introduction valve V9 and the drainage valve V10 and driving the introduction pump 16, the intermediate concentrated sample water stored in the intermediate concentrated sample water tank 23 is guided to the membrane filter unit 17, Here, the microorganisms including the microorganisms to be collected are separated from the intermediate concentrated sample water, and the sample water that has permeated through the membrane filter unit 17 is drained through the drain valve V10. By providing two stages of hollow fiber membrane separation units, the amount of concentrated sample water stored in the intermediate concentrated sample water tank 23 can be reduced to a very small amount. Can also be reduced. For example, a membrane filter with a smaller diameter can be selected, a compact unit can be configured, and the amount of filtration can be reduced, so that blockage of the membrane can be reduced.

  In the third embodiment, the hollow fiber membrane separation unit has a two-stage configuration, but more than that may be provided, and the capacity of the concentrated sample water can be reduced to a very small amount.

  FIG. 5 is a system diagram showing the configuration of the fourth embodiment of the microorganism collection apparatus of the present invention. In the figure, the same elements as those of the first embodiment shown in FIG. In this embodiment, a cleaning solution introduction valve V31 and a washing solution introduction unit 31 are provided in a path upstream from the sample water introduction tank 11, and all other than that of the first embodiment shown in FIG. It is configured identically. Among these, the cleaning solution introduction valve V31 is opened and closed in accordance with the water sampling valve V1. The cleaning solution is a solution containing a surfactant. Although the kind of surfactant is not specifically limited, For example, mixed solutions, such as Tween80, sodium pyrophosphate, and EDTA3 sodium, are introduce | transduced. The ratio of the amount added to the sample water is arbitrary. The surfactant is selected from anionic, cationic, nonionic, etc., depending on the surface charge of the microorganism to be collected.

  The operation of the fourth embodiment configured as described above will be described particularly with respect to the parts different from those in FIG. The water sampling valve V1 is opened to introduce the sample water into the sample water introduction tank 11, and at the same time, the washing solution introduction valve V31 is opened to introduce the washing solution from the washing solution introduction unit 31. The introduction flow rate is arbitrary. By circulating and filtering the sample water together with the solution containing the surfactant by the cross flow filtration method, components adhering to the pipe wall, the surface of the hollow fiber membrane, etc. can be peeled off at any time. Thereby, it becomes possible to improve the recovery rate of microorganisms in the hollow fiber membrane separation unit 13.

  FIG. 6 is a system diagram showing the configuration of the fifth embodiment of the microorganism collecting apparatus according to the present invention. In the figure, the same elements as those of the first embodiment shown in FIG. In this embodiment, a cleaning solution introduction valve V41 and a washing solution introduction unit 41 are provided in a path upstream from the backwash pump 14, and all other parts are the same as those in the first embodiment shown in FIG. It is configured. Among these, the cleaning solution introduction valve V41 is opened and closed in accordance with the drive of the backwash pump 14. The cleaning solution is a solution containing a surfactant. Although the kind of surfactant is not specifically limited, For example, mixed solutions, such as Tween80, sodium pyrophosphate, and EDTA3 sodium, are introduce | transduced.

  The operation of the fifth embodiment configured as described above will be described particularly with respect to the parts different from those in FIG. After a predetermined amount of sample water is filtered by the hollow fiber membrane separation unit 13, the process proceeds to a hollow fiber membrane washing step. The introduction valve V2 and the circulating water flow path valve V5 are closed, the intermediate concentrated sample water recovery valve V8 is opened, and the backwash pump 14 is driven. At this time, the cleaning solution introduction valve V41 is simultaneously opened, and the cleaning solution is introduced from the cleaning solution introduction unit 41. The introduction flow rate is arbitrary. Thereby, the backwash water containing the cleaning solution is supplied to the hollow fiber membrane separation unit 13, and the intermediate concentrated sample together with the backwash water supplied with a certain amount or a predetermined time of microorganisms including the microorganisms to be collected attached to the hollow fiber membrane surface. The water tank 15 is drained.

  Next, by closing the unit inlet valve V3 and the unit outlet valve V4 and opening the inlet valve V2 and the circulating water passage valve V5, the backwash water is supplied to the circulating water passage, the sample water introduction tank 11 and the introduction pump 12. Then, the microorganisms including the microorganisms to be collected attached to the pipe and the like are drained into the intermediate concentrated sample water tank 15 together with the backwash water supplied for a certain amount or for a certain time. The amount of backwash water supplied is very small compared to the sample water. Further, the sample water that has passed through the hollow fiber membrane separation unit 13 may be used as the backwash water. The backwash pump 14 is stopped, all valves are closed, and the backwash process is completed.

  Thus, the component adhering to the piping wall, the hollow fiber membrane surface, etc. can be effectively peeled off by adding a solution containing a surfactant and backwashing. Thereby, it becomes possible to improve the recovery rate of microorganisms in the hollow fiber membrane separation unit 13.

  In particular, a solution containing a surfactant may be added to the backwash water in advance without providing the cleaning solution introduction valve V41 and the cleaning solution introduction unit 41. Moreover, the ratio of the addition amount with respect to the backwash solution is arbitrary.

  FIG. 7 is a diagram for comparing and comparing the performances of the microorganism recovery method according to the present invention. FIG. 7 shows the results of comparison of the recovery rate between the condition in which the solution containing the surfactant is not introduced and the introduced condition. Furthermore, when introduced, the case of adding to the sample water and the case of adding to the cleaning liquid are shown together. When a solution containing a surfactant was introduced, it was introduced at a rate of 0.05 vol% with respect to the sample water and the cleaning solution. As shown in FIG. 7, under the condition where the solution containing the surfactant is not introduced, microorganisms may remain in the pipe or on the surface of the hollow fiber membrane, and the recovery rate is low. The recovery rate is improved by the introduction of the surfactant. Therefore, it turns out that introduction | transduction of surfactant is effective.

  FIG. 8 is a system diagram showing the configuration of the sixth embodiment of the microorganism collection apparatus of the present invention. In the figure, the same elements as those of the first embodiment shown in FIG. In this embodiment, the hollow fiber membrane separation unit 13 is provided with a unit 51 for applying a physical factor, and all other configurations are the same as those of the first embodiment shown in FIG. The unit 51 operates at the time of backwashing, and for example, ultrasonic irradiation is used as a physical factor. The ultrasonic element 51a is brought into close contact with the outer surface of the casing constituting the hollow fiber membrane separation unit 13, and the ultrasonic element 51a is driven by the ultrasonic oscillator 51b.

  The operation of the sixth embodiment configured as described above will be described particularly with respect to the parts different from those in FIG. After a predetermined amount of sample water is filtered by the hollow fiber membrane separation unit 13, the process proceeds to a hollow fiber membrane washing step. The introduction valve V2 and the circulating water flow path valve V5 are closed, the intermediate concentrated sample water recovery valve V8 is opened, and the backwash pump is driven. At this time, the ultrasonic oscillator 51b is simultaneously driven to vibrate the hollow fiber membrane separation unit 13 itself from the outer surface of the casing constituting the hollow fiber membrane separation unit 13 by the ultrasonic element 51a. To peel off. The frequency and intensity of the ultrasonic wave are selected as appropriate. As a result, the backwash water containing the cleaning solution is supplied to the hollow fiber membrane separation unit 13, and the microbe including the microorganisms to be collected adhering to the hollow fiber membrane surface is intermediate with the backwash water supplied for a certain amount or for a certain time. The concentrated sample water tank 15 is drained. The unit inlet valve V3 and the unit outlet valve V4 are closed, the ultrasonic oscillator 51b is stopped, and the back washing process of the hollow fiber membrane separation unit 13 is completed. Thereby, peeling and collection | recovery of a capture thing can be accelerated | stimulated from the hollow fiber membrane surface, and microorganisms can be collect | recovered efficiently.

    In the sixth embodiment, instead of irradiating the ultrasonic wave, the physical factor may be mechanical vibration, electrical vibration, air bubbling, etc., and in essence, the separation and recovery of the captured matter are promoted. If a physical factor is provided, the same effect as described above can be obtained. In the sixth embodiment, physical factors may be applied not only during backwashing but also during the filtration process, whereby microorganisms can be efficiently recovered.

The systematic diagram which shows the structure of 1st Embodiment of the microbe collection | recovery apparatus which enforces the microbe collection method which concerns on this invention. The conceptual diagram of the crossflow filtration system for demonstrating operation | movement of 1st Embodiment shown in FIG. The systematic diagram which shows the structure of 2nd Embodiment of the microbe collection | recovery apparatus which enforces the microbe collection method which concerns on this invention. The systematic diagram which shows the structure of 3rd Embodiment of the microbe collection | recovery apparatus which enforces the microbe collection method which concerns on this invention. The systematic diagram which shows the structure of 4th Embodiment of the microbe collection | recovery apparatus which enforces the microbe collection method which concerns on this invention. The systematic diagram which shows the structure of 5th Embodiment of the microbe collection | recovery apparatus which enforces the microbe collection method which concerns on this invention. The figure which compared and contrasted the performance of the collection | recovery method of the microorganisms which concern on this invention. The systematic diagram which shows the structure of 6th Embodiment of the microbe collection | recovery apparatus which enforces the microbe collection method which concerns on this invention.

Explanation of symbols

11 Sample water introduction tanks 12, 16, 21 Introduction pumps 13, 22 Hollow fiber membrane separation unit 13a Hollow fiber membrane 14 Backwash pumps 15, 23 Intermediate concentrated sample water tank 17 Membrane filter unit 18 Pump for elicited liquid injection 31, 41 Cleaning solution introduction unit 51 Unit 51a for applying physical factors Ultrasonic element 51b Ultrasonic oscillator V1 Water sampling valve V2 Introduction valve V3, V22 Unit inlet valve V4, V23 Unit outlet valve V5, V24 Circulating water flow path valve V6, V25 Unit Permeated Water Valves V7, V26 Backwash Valves V8, V27 Intermediate Concentrated Sample Water Recovery Valves V9, V21 Intermediate Concentrated Sample Water Introducing Valve V10 Drain Valve V11 Elicited Solution Injection Valve V12 Sample Water Drain Valve V31 , V41 Cleaning solution introduction valve

Claims (10)

In a microorganism recovery method for recovering target microorganisms in water,
Separating and concentrating the target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
Separating the target microorganisms separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a smaller amount of solution than water before separation and concentration; and
Further separating, concentrating, and immobilizing the target microorganism using a membrane filter with a backwash solution in which the target microorganism is concentrated by backwashing;
Are sequentially executed. In a microorganism recovery method for recovering target microorganisms in water,
Separating and concentrating the target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
Separating the target microorganisms separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a smaller amount of solution than water before separation and concentration; and
Further separating and concentrating the target microorganism using a membrane filter with a backwash solution in which the target microorganism is concentrated by backwashing; and
Peeling the target microorganisms separated and concentrated by the membrane filter with a smaller amount of solution than the backwash solution;
Are sequentially executed.   3. The microorganism recovery method according to claim 1, wherein the target microorganism is a chlorine-resistant pathogenic microorganism. In a microorganism recovery device that recovers target microorganisms in water,
Means for separating and concentrating the target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
Means for separating and concentrating the target microorganism separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a solution in an amount smaller than that of water before separation and concentration;
Means for further separating, concentrating, and immobilizing the target microorganism using a membrane filter with a backwash solution in which the target microorganism is concentrated by backwashing;
An apparatus for collecting microorganisms, comprising: In a microorganism recovery device that recovers target microorganisms in water,
Means for separating and concentrating the target microorganisms in water using a cross-flow filtration type hollow fiber membrane;
Means for separating and concentrating the target microorganism separated and concentrated by the hollow fiber membrane from the hollow fiber membrane by backwashing with a solution in an amount smaller than that of water before separation and concentration;
Means for further separating and concentrating the target microorganism using a membrane filter with a backwash solution in which the target microorganism is concentrated by backwashing;
Means for separating the target microorganism separated and concentrated by the membrane filter with a smaller amount of solution than the backwash solution;
An apparatus for collecting microorganisms, comprising:   Means for separating and concentrating the target microorganisms in water using a cross-flow filtration type hollow fiber membrane, and the target microorganisms separated and concentrated by the hollow fiber membrane than the water before separation and concentration The microorganism recovery apparatus according to claim 4 or 5, comprising a plurality of stages of means for backwashing with a small amount of solution and separating from the hollow fiber membrane.   The microorganism collection apparatus according to any one of claims 4 to 6, wherein the target microorganism is a chlorine-resistant pathogenic microorganism.   8. A solution containing a surfactant in sample water is added, and the target microorganism in water is separated and concentrated using a cross-flow filtration type hollow fiber membrane. The microorganisms collection apparatus as described in the item.   A solution containing a surfactant is added to the backwash solution of the hollow fiber membrane, and the target microorganism separated and concentrated by the hollow fiber membrane is backwashed with a smaller amount of solution than the water, and the hollow The microorganism collecting apparatus according to any one of claims 4 to 7, wherein the microorganism collecting apparatus peels off from the yarn film.   The microorganism collection apparatus according to any one of claims 4 to 9, further comprising means for physically accelerating the peeling operation of the target microorganism from the hollow fiber membrane.

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