JP2003181477A - Treatment system for city water, treatment method and city water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide techniques to quickly find drinking city water contaminated with harmful microorganisms such as harmful bacteria, to remove the harmful microorganisms on a high level and to rapidly prevent supply of the contaminated drinking city water to consumers. <P>SOLUTION: A device for removing harmful microorganisms, a filter device for harmful microorganisms and a detection device for harmful microorganisms are combined for use. The water flow preferably includes a buffer passage with piston-flow property. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a system for treating drinking water, which detects microorganisms harmful to the human body,
It is related to the removal technology.

[0002]

2. Description of the Related Art Conventionally, drinking water has been supplied to consumers after subjecting raw water taken from dams, rivers, etc. to biological treatment, coagulation sedimentation treatment, sand filtration, chlorine treatment, activated carbon treatment, etc. .

[0003]

However, since dams and rivers are widely accessible to the general public, there is a risk that harmful microorganisms such as harmful bacteria will flow into the raw water due to intentional or accidental causes.

These harmful microorganisms cannot be said to be sufficiently removed by the conventional treatment system for drinking water for tap water as described above, and there is a risk of contaminated tap water flowing out.

An object of the present invention is to prevent drinking tap water, which is contaminated with harmful microorganisms such as harmful bacteria due to a cause such as intentional or accidental, from reaching a consumer.

[0006] Still another object and advantage of the present invention are:
It will be apparent from the following description.

In the present invention, drinking tap water may be simply referred to as tap water.

[0008]

One aspect of the present invention is a tap water treatment system comprising a combination of a harmful microorganism removing device, a harmful microorganism filter device, and a harmful microorganism detecting device.

By combining a harmful microorganism removing device, a harmful microorganism filter device, and a harmful microorganism detecting device, it is possible to quickly find drinking water for drinking water contaminated with harmful microorganisms such as harmful bacteria. It is possible to remove harmful microorganisms at a level, and prevent contaminated drinking water from reaching consumers. Moreover, this prevention can be performed quickly.

Another aspect of the present invention is a method for treating tap water using the system described above, wherein when harmful microorganisms are detected, the harmful microorganisms removing device located after the location where the sample is obtained. Step of strengthening harmful microorganisms removal conditions, step of strengthening filtration conditions of the filter device for harmful microorganisms after the location where the sample was obtained, and step of interrupting the supply of tap water at the outlet of the buffer flow path The method for treating tap water includes performing at least one of

By this method, it is possible to prevent drinking tap water contaminated with harmful microorganisms such as harmful bacteria from reaching the consumers.

Still another aspect of the present invention is tap water treated by the above method for treating tap water.

Use of such tap water ensures much higher safety than usual.

In the present invention, the water treatment system for tap water is
It is preferable that the water flow includes a buffer flow path having a piston flow property.

With such a buffer flow path, even if it takes time for the harmful microorganism detection device to detect the harmful microorganisms, the harmful microorganisms are closed before they reach the outlet of the buffer flow path. This is because it is possible to prevent drinking tap water contaminated with harmful microorganisms such as harmful bacteria from reaching the consumers.

It is further preferable that the buffer flow path has a residence time that is three times or more the detection time in the harmful microorganism detection device.

With this retention time, even if the position where the sample for analysis is taken is just before the flow path for the buffer, the harmful microorganisms are allowed to come out before reaching the exit of the flow path for the buffer. This is because it is possible to prevent the drinking tap water, which is contaminated with harmful microorganisms such as harmful bacteria, from reaching the consumers by closing the door. More preferably, it is 5 times or more instead of 3 times or more.

Further, in the present invention, it is desirable that the harmful microorganism removing device is an ozone treatment device. This is because it has excellent sterilizing ability and can be easily used.

Regarding the processing conditions by the ozone processing apparatus, it is preferable that the ozone concentration is 2 ppm by weight or more and the processing time is 2 minutes or more. This is because 99.9% of the spores can be killed under this condition. More preferably, the processing time is 20 minutes or more.

Further, in the present invention, it is preferable that the harmful microorganism detecting device has a function of detecting B. anthracis.

It is because Bacillus anthracis has a high possibility of being used in the biological terrorist activity and has a great influence on the public.

Further, in the present invention, it is preferable that the water treatment system for tap water has an electron beam treatment device for sterilizing the filter device for harmful microorganisms. This is because if harmful microorganisms reach the filter device for harmful microorganisms, it is possible to quickly sterilize them.

As for the order of installing the above devices, a harmful microorganism filter device is installed downstream of the harmful microorganism removing device, and a buffer channel is installed downstream of the harmful microorganism filter device. Is a sample collected before the harmful microorganism removing device, between the harmful microorganism removing device and the harmful microorganism filter device, between the harmful microorganism filter device and the buffer flow path, or after the buffer flow path. It is preferably adapted for analysis.

If a filter device for harmful microorganisms is installed downstream of the device for removing harmful microorganisms, harmful microorganisms that could not be sterilized by the device for removing harmful microorganisms are effectively filtered by the filter device for harmful microorganisms together with the dead bodies of the killed harmful microorganisms. If it is possible to collect, if there is a buffer flow path downstream of the harmful microorganism filter device, when harmful microorganisms are detected,
This is because it is possible to prevent drinking tap water contaminated with harmful microorganisms from reaching the consumers.

If a sampling place is provided as described above, there is a great possibility that drinking tap water contaminated with harmful microorganisms can be detected by the time it reaches the consumer and prompt treatment can be taken. Because it will be.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. It should be noted that these drawings and description are for exemplifying the present invention and do not limit the scope of the present invention. It goes without saying that other embodiments may belong to the scope of the present invention as long as they match the gist of the present invention.

FIG. 1 is a model diagram of a tap water treatment system according to the present invention.

In FIG. 1, raw water stored in a reservoir 1 is condensed by a water pump 2 in a rapid filtration sterilizer 3.
After being subjected to a precipitation treatment and a chlorine sterilization treatment, it is treated with the harmful microorganisms removing device 5 according to the present invention through the preliminary filter 4, and then with the harmful water microorganisms filtering device 7 according to the present invention through the water supply pump 6. The body of harmful microorganisms is removed by filtration, and if there is any harmful microorganism that is not removed, it is removed by filtration and supplied to the consumer 10 via the buffer channel 8 and the water pump 9 according to the present invention. Has been done. The harmful microorganism detecting device 11 is arranged at the sample position 12a ...
It is arranged so that a sample water can be automatically obtained by collecting a sample from 12d.

The harmful microorganism filter device 7 can be sterilized by irradiation treatment with an electron beam treatment device (not shown). In the case of sterilization, a method of taking out the filter part from the harmful microorganism filter device 7 to sterilize it, or switching the filter part on the spot, and irradiating the filter part which has been discontinued with the electron beam treatment device on the spot It can be appropriately performed using a known technique such as treatment.

In the present invention, the term "consumer" generally means a person who ultimately consumes the water for drinking, cooking, or eating, like a general citizen. However, any other case may be used.

Examples of harmful microorganisms in the present invention include bacteria such as anthrax, pesto, and botulinum, and viruses such as smallpox virus.

As the rapid filtration sterilizer 3, as shown in FIG. 2, a rapid mixing tank 21, a floc formation tank 22, a precipitation tank 23, a rapid filtration tank 24, and a chlorine sterilizer 25 are connected in series. .

The preliminary filter 4 reduces the filtration load of the harmful microorganism filter device 7 located downstream thereof, and is not an essential element for the present invention. A known filter can be appropriately selected and used.

The harmful microorganism removing device according to the present invention is a device intended to remove the harmful microorganisms described above, and does not include a flocculating / precipitating device and a filtering device using sand or a filter.

Specific examples include a combination of a strong chlorine sterilizer and a dechlorinator, an ozone treatment device, an oxidation treatment device by a supercritical water oxidation method, and the like. Any known one may be used as long as it matches the gist of the present invention.

As an ozone treatment apparatus, as shown in FIG. 3, an apparatus having an ozone generator 31, an ozone reaction tank 32, an ozone treatment water tank 33, and an exhaust ozone treatment apparatus 34 as main parts can be exemplified.

The filter device for harmful microorganisms according to the present invention is a device for removing the harmful microorganisms and carcasses sterilized by the harmful microorganisms, and is a microfiltration membrane capable of filtering 0.1 μm or more. , Ultrafiltration membrane capable of filtering 0.1 to 1 μm microorganisms, virtual maximum size is 1n
Examples thereof include a nanofiltration membrane having an m level, a reverse osmosis membrane that allows only water molecules to pass through and does not allow other solutes to pass through.

FIG. 4 is a model representation of the range of the filter particle size of these filters and the size of the object to be filtered.

As the harmful microorganism detecting device, any known technique can be used depending on the harmful microorganism to be targeted.

For example, a detection method combining a gene amplification method by PCR (polymerase chain reaction) and an electrophoresis method, a method using a DNA chip on which a DNA amplification module and a DNA probe are immobilized, and an antigen-antibody reaction are used. Then, a fluorescent substance is added to the corresponding antibody, and this is reacted with a microorganism to detect fluorescence.

As a detection method combining the gene amplification method by PCR (polymerase chain reaction) and the electrophoresis method, for example, the apparatus and method disclosed in Japanese Patent Laid-Open No. 7-75544 can be used.

Further, another apparatus / method disclosed in Japanese Patent Laid-Open No. 2000-88854 can be used.

In the case of anthrax, for example, the detection time of harmful microorganisms by such a device is 40 minutes to 1 hour, which is the shortest example. Depending on the type of harmful microorganisms, it may take several hours or longer. It is also possible to use a method in which the number of particles is continuously counted by a particle counter using a laser or the like, and harmful microorganisms are detected only when the number rapidly increases.

A plurality of such detection devices may be installed.

A plurality of combinations of the harmful microorganism removing device and the harmful microorganism filter device may be combined.
The numbers of the harmful microorganism removing device and the harmful microorganism filter device may not be the same. Further, it may include a case where a harmful microorganism removing device is installed downstream of the harmful microorganism filter device. Further, the harmful microorganism detecting device may be one or plural.

The harmful microorganism detecting device 11 is located at the sample position 1
The pipes are arranged so that the sample water can be automatically obtained by collecting the samples from 2a to 12d, but it is not always necessary to use the pipes, and other methods such as transferring the sample container may be used. Alternatively, a person may sample and carry it.

The buffer flow path is intended to cover the time delay required for the detection of harmful microorganisms by the residence time of water in the flow path, and has a piston flow property to prevent the bypass flow of the water flow. It is desirable to do.

Specifically, a baffle for dividing the flow is preferably installed, but other known methods may be used.

From the viewpoint of the flow velocity, having a piston flow property can be defined as that the flow as a whole is substantially laminar. Considering the adverse effects of diffusion and convection, it is also desirable that the flow velocity is sufficiently higher than that of mixing by diffusion and convection. A flow velocity of 0.1 m / sec or more is more desirable.

In the above description, it is desirable that the residence time of the buffer channel is three times or more than the detection time of the harmful microorganism detecting device. For example, it takes 40 minutes from sampling to detection. In this case, it is preferable to have a residence time of 2 hours or more.

This residence time is obtained by dividing the volume of the buffer channel by the flow velocity of water.

It should be noted that a specific chemical is added to the inlet of the buffer channel, its concentration is measured at the outlet of the buffer channel, and the time required until an appropriate time when the concentration gradually increases is measured. A method of determining a desired residence time by adding a predetermined safety factor to the measurement time is also conceivable.

The size of the buffer channel can be calculated as a model as follows.

(Specifications) -Water consumption: 400 L / person-day-Number of target consumers to supply: 100,000-Time from sample collection to detection of harmful microorganisms: 40 minutes (required retention of buffer flow path) Amount = required volume) 400 × 100,000 × (40 / (24 × 60)) × 3 = (about) 3,000 m ³ .

In FIG. 1, a harmful microorganism filter device is installed downstream of the harmful microorganism removing device, and a buffer flow path is installed downstream of the harmful microorganism filter device. Prior to the above, samples collected from between the harmful microorganism removing device and the harmful microorganism filter device, between the harmful microorganism filter device and the buffer flow path, and after the buffer flow path are analyzed.

By installing the harmful microorganisms removing device, the harmful microorganisms filter device and the buffer flow path in this way, first, the harmful microorganisms are sufficiently sterilized by the harmful microorganisms removing device. Filtered and collected with a filter device for harmful microorganisms together with the dead bodies of microorganisms,
Further, in case of emergency, the outlet of the buffer channel can be closed to prevent the contaminated tap water from flowing out.

The harmful microorganism detecting apparatus 11 collects samples from various sample positions because it has its own effect.

The use of the sample position 12a can enhance the harmful microorganism removing device and the harmful microorganism filter device downstream of the sample position 12a.

When the sample position 12b is used, it is possible to quickly recognize that the harmful microorganisms have not been removed by the harmful microorganisms removing device, and if there is a harmful microorganisms removing device or a harmful microorganisms filter device downstream thereof, strengthen it. can do.

When the sample position 12c is used, it is possible to quickly recognize that the harmful microorganisms have failed to be removed by the harmful microorganism filter device and the urgency has finally increased. If present, the filter device can be reinforced.

Further, when there is no harmful microorganisms removing device or harmful microorganisms filter device downstream thereof, the outlet of the flow path for the buffer is closed and drinking tap water contaminated with harmful microorganisms is sent to the consumer. Can be prevented from reaching.

When the sample position 12d is used, it is possible to promptly recognize that the contaminated tap water has flown to the outside, and to promptly give an alarm to the citizens who are consumers.

Here, to strengthen the harmful microorganisms removing device means to make the conditions of the harmful microorganisms removing treatment severe.

For example, the ozone treatment condition is preferably an ozone concentration of 2 mass ppm or more and a treatment time of 20 minutes or more, but the normal treatment condition is an ozone concentration of 2 mass ppm,
When the treatment time of 20 minutes is adopted, the ozone concentration is increased and / or the treatment time is extended from that.

Strengthening the filter device for harmful microorganisms means stricter conditions for filtering harmful microorganisms.

For example, when a microfiltration membrane is used, switching to multi-stage treatment, using a nanofiltration membrane together, or reducing the flow rate of water corresponds to this.

Although FIG. 1 shows the case of a large-scale tap water treatment system, the present invention can be applied to a scale of several tens of people.

FIG. 5 shows a small-scale tap water treatment system, that is, a tap water treatment system on the consumer side which has already been supplied through a normal treatment. As described above, the present invention also includes in its category a case where a normal filtration / sterilization treatment device is not necessarily included.

In FIG. 5, tap water is once stored in a storage tank 41, processed by a pump 42, treated by a harmful microorganism removing device 43 according to the present invention, and then, passed through a water feed pump 44, through a harmful microorganism filter according to the present invention. The device 45 removes harmful microorganisms by filtration, and supplies them to the end consumer 48 via the buffer channel 46 and the water supply pump 47 according to the present invention.

As a system to which such a system is applied, for example, various devices according to the present invention are installed in one place in a laboratory, and tap water is supplied to each research facility scattered therein as an end consumer. There are cases.

The size of the buffer flow path in the case of such a small-scale system can be calculated as a model as follows.

(Specifications) -Water consumption: 400 L / person-day-Number of target consumers to be supplied: 150-Time from sample collection to detection of harmful microorganisms: 40 minutes (required retention amount in buffer channel) = Required volume) 400 × 150 × (40 / (24 × 60)) × 3 = (about) 5 m ³ .

As the water to be treated in the present invention, as can be judged from the above explanation, water after purification of raw water in a water purification plant or general purification treatment is completed, It also covers the water supplied to, that is, what is generally called tap water.

In the present invention, the term "tap water" means such water.

The target of application of the present invention may be a water purification plant in a municipality, a large-scale hotel, an apartment house, an apartment, a housing complex, or the like.

By supplying the tap water treated by the above-described method for treating tap water to such an object, much higher safety than usual can be secured.

[0077]

EFFECTS OF THE INVENTION It is possible to quickly find out drinking water for drinking which is contaminated with harmful microorganisms such as harmful bacteria and prevent the contaminated drinking water from reaching consumers. Moreover, this prevention can be performed quickly.

[Brief description of drawings]

FIG. 1 is a model diagram of a tap water treatment system according to the present invention.

FIG. 2 is a diagram showing a model of a rapid filtration sterilizer.

FIG. 3 is a diagram showing a model of an ozone processing apparatus.

FIG. 4 is a diagram showing a model of a range of a filter particle size of a filter and a size of an object to be filtered.

FIG. 5 is a model view showing an example of a small-scale tap water treatment system according to the present invention.

[Explanation of symbols]

1 reservoir 2 water pump 3 Rapid filtration sterilizer 4 preliminary filter 5 Harmful microorganisms removal device 6 water pump 7 Filter device for harmful microorganisms 8 buffer channels 9 water pump 10 consumers 11 Hazardous microorganisms detection device 12a-12d sample position 21 Rapid mixing tank 22 Flock forming tank 23 Settling tank 24 Rapid filtration tank 25 chlorine sterilizer 31 Ozone generator 32 Ozone reaction tank 33 Ozone-treated water tank 34 Exhaust ozone treatment device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C02F 1/50 520 C02F 1/50 520C 520D 531 531R 540 540A 550 550L 560 560C 560E 560Z (72) Inventor Ukawa Naohiko 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Prefecture Mitsubishi Heavy Industries, Ltd. Hiroshima Research Laboratory F-term (reference) 4D006 GA03 GA06 GA07 KA01 KB13 KB14 KB30 KC21 KE03Q KE30P LA08 PB02 PB24 PC51 4D050 AA03 AB06 AB46 BB02 BB04 BD06 BD08 CA09

Claims (13)

[Claims] 1. A tap water treatment system comprising a combination of a harmful microorganism removing device, a harmful microorganism filter device, and a harmful microorganism detecting device. 2. A buffer flow path having a residence time that is three times or more the detection time in a harmful microorganism detection apparatus, wherein the water flow therein includes a buffer flow path having a piston flow property. The tap water treatment system according to claim 1. 3. The tap water treatment system according to claim 1, wherein the harmful microorganism removing device is an ozone treating device. 4. The tap water treatment system according to claim 3, wherein the ozone treatment device has a treatment condition of ozone concentration of 2 ppm by weight or more and treatment time of 20 minutes or more. 5. The tap water treatment system according to claim 1, wherein the harmful microorganism detecting device has a function of detecting anthrax. 6. An electron beam treatment device for sterilizing a filter device for harmful microorganisms.
The water treatment system for tap water according to any one of to 5. 7. A harmful microorganism removing device, a harmful microorganism filter device installed downstream of the harmful microorganism removing device, a buffer flow path installed downstream of the harmful microorganism filter device, and the harmful microorganism. At least one of before the removing device, between the harmful microorganism removing device and the harmful microorganism filter device, between the harmful microorganism filter device and the buffer flow passage, and after the buffer flow passage. The water treatment system for tap water according to any one of claims 2 to 6, further comprising: a harmful microorganism detection device that analyzes a sample collected from the water treatment system. 8. A harmful microorganism removing device, a harmful microorganism filter device, a harmful microorganism detecting device, and a buffer flow path having a residence time three times or more the detection time of the harmful microorganism detecting device, A method for treating tap water using a tap water treatment system in which the water flow inside includes a buffer flow path having a piston flow property, and when harmful microorganisms are detected, the method is after the location where the sample was obtained. The step of strengthening the harmful microorganisms removal condition of the harmful microorganisms removal device, the step of strengthening the filtration conditions of the filter device for harmful microorganisms after the location where the sample was obtained, and the tap water outlet at the outlet of the buffer channel. A method for treating tap water, comprising performing at least one of a step of shutting off the supply. 9. The method for treating tap water according to claim 8, wherein the harmful microorganism removing device is an ozone treating device. 10. The method for treating tap water according to claim 9, wherein the treatment condition by the ozone treatment device is an ozone concentration of 2 ppm by weight or more and a treatment time of 20 minutes or more. 11. The method for treating tap water according to claim 8, wherein the harmful microorganism detecting device has a function of detecting anthrax. 12. The method for treating tap water according to claim 8, wherein the tap water treatment system has an electron beam treatment device for disinfecting a filter device for harmful microorganisms. 13. Tap water treated by the method for treating tap water according to any one of claims 8 to 12.