JPH11216469A - Fresh water unit - Google Patents

Abstract

(57) [Summary] [Problem] To provide an inexpensive fresh water generating unit that is small, lightweight, and convenient to handle. SOLUTION: A filter unit 20 for filtering raw water.
And a separation membrane unit 30 for treating the water treated by the filter unit 20 using a separation membrane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fresh water producing unit in which raw water is filtered by a filter unit and then separated by a separation membrane unit using a separation membrane such as a reverse osmosis membrane.

[0002]

2. Description of the Related Art Liquid separation by a reverse osmosis method using a separation membrane such as a semipermeable membrane has been put to practical use in various fields such as seawater desalination, production of ultrapure water, and concentration of a solution. The separation membrane module used in the reverse osmosis membrane method is mainly of the spiral type or hollow fiber membrane type, but if the target raw water is supplied directly to the separation membrane module, fine particles, suspended solids, bacteria , Algae and the like easily cause clogging, and fouling occurs on the surface of the membrane, which causes a significant decrease in membrane separation performance. Therefore, when liquid separation is performed by a reverse osmosis membrane separation unit, as a pretreatment step, removal of fine particles, suspended matter, and the like is performed by an ultrafiltration membrane (UF), a microfiltration membrane (MF), a cartridge filter, various filter materials, and the like. Do. In general, reverse osmosis membranes often have membrane performance that is reduced by residual chlorine, and require a pretreatment unit for the purpose of removing chlorine from raw water.

[0003] In such a fresh water producing unit, the pretreatment unit and the reverse osmosis membrane module unit are usually configured as separate units, so that the total volume and weight are large. However, a relatively small-sized one is required especially for a mobile-type fresh water generating unit that performs low-pressure operation, for example, an emergency fresh water generator used in an emergency such as an earthquake, storm and flood damage, or fire. As the mobile fresh water generating unit, one described in Japanese Patent Application Laid-Open No. 6-91262 is known. This device moves to rivers, lakes, marshes, ponds, pools, fire tanks and other water sources in the disaster area when water or power supply is cut off, and removes suspended solids and salt from raw water. It removes mixed or dissolved components to produce drinking water, living water such as bath water or washing water. However, this device has an overall volume,
Because of their large weight, they have not sufficiently responded to the demand for miniaturization.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a device which is particularly suitable as a mobile, small-sized, low-pressure operation desalination unit. For example, when used for emergency water desalination machines, water tanks for disaster prevention prepared by municipalities such as municipalities, large-scale hospitals and companies, and disaster preparedness in case of earthquake, storm and flood damage, fire, etc. In the event of an emergency such as an earthquake, storm or flood, or a fire, the fire extinguishing engine that has finished or does not perform a fire extinguishing operation, etc. Provide a desalination unit that can quickly and easily produce a large amount of drinking water (purified water) and domestic water (bath water or washing water) at a low cost, and that is easy to maintain and requires a small storage space. It is in.

[0005]

Means for Solving the Problems To solve the above problems, a fresh water producing unit of the present invention comprises a filter unit for filtering raw water, and a separation membrane unit for treating water treated by the filter unit by using a separation membrane. Are connected directly to each other via a common head.

In this desalination unit, the filter unit and the separation membrane unit are directly connected coaxially via the common head, or the filter unit and the separation membrane unit form a common head. And a structure that is directly connected in parallel.

As the filter unit, a unit having a built-in cartridge type filter element can be used. As the cartridge type filter element, for example, an element containing activated carbon can be used. Further, as the cartridge type filter element, an element which is contained in a container that can see through the inside, for example, the entire container is transparent, or at least a part thereof is configured as a transparent part so that the internal state can be checked. Those in a container are preferred.

It is preferable that the separation membrane unit is provided with, for example, a spiral-type module capable of having a compact configuration as a separation membrane module. Further, as the separation membrane, for example, raw water pressure 500 kPa,
At a temperature of 25 ° C. and a NaCl concentration of 500 mg / l in raw water, the water permeability is at least 0.5 m ³ / m ^2.
Reverse osmosis membranes with a Cl rejection of at least 98% can be used. Such a reverse osmosis membrane is particularly suitable as a separation membrane for emergency fresh water production. The reverse osmosis membrane can be composed of, for example, a polyether-based composite membrane, an aromatic polyamide-based composite membrane, an aliphatic polyamide-based composite membrane, a cellulose acetate-based asymmetric membrane, or the like.

It is preferable that a relief valve is provided in the upper filter unit. Further, it is preferable that a backflow prevention mechanism is provided at each of the inlet of the filter unit and the outlet of the separation membrane unit. Or,
It is preferable that a constant flow rate mechanism is provided at the outlet of the separation membrane unit.

[0010] The use of the fresh water generating unit thus configured is not particularly limited, but is particularly suitable for emergency fresh water.

The fresh water producing method according to the present invention comprises a method for producing a desired liquid using the above fresh water producing unit.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with preferred embodiments. The desalination unit according to the present invention, in particular, a desalination unit using a reverse osmosis membrane, can be applied to various fields such as desalination of drinking water and domestic water, desalination of seawater, production of pure water, and concentration of food. can do. In addition, depending on the application, the target liquid can be produced by using various filters, a microfiltration device, an ion exchanger, a degassing membrane device, a chemical addition device, a sterilization treatment device, and the like.

There are various types of modules using a reverse osmosis membrane as a liquid separation membrane in terms of the desalination ratio and the amount of fresh water depending on the application. In general, when treating raw water with low osmotic pressure, it is appropriate to use a low-pressure type with low desalination performance and high water production, and when high osmotic pressure, use a high-pressure type with high desalination performance. It is.

The material of the element of the cartridge type filter used in the present invention is not particularly limited, but polyethylene, polypropylene, polysulfone, phenol resin, acetylcellulose, glass fiber, rayon, cotton, stainless steel and the like can be used. is there. As the shape, hollow fiber, pleated, wind type,
There are sintered metals and the like, and those having a filtration accuracy of 1 micron or less to several tens of microns are commercially available. Further, as a container for accommodating the filter element, a cartridge using polypropylene, polysulfone, phenol, polycarbonate resin, stainless steel, or the like is commercially available, so that it can be selected according to use conditions. When the inside of the filter element can be seen through, for example, at least a part of the filter element is transparent, the degree of clogging of the filter element can be easily visually checked from the outside, which is convenient. Also, a granular activated carbon such as coconut shell charcoal, or an activated carbon cartridge filled with activated carbon fibers can be used. In the case of using granular activated carbon, those having different activated carbon particle sizes are commercially available, so that it is possible to select one suitable for the intended use.

The reverse osmosis membrane module as the separation membrane module used for the separation membrane unit in the present invention includes a flat membrane type, a hollow fiber type, a spiral type, etc., and the type is not particularly limited. It is preferable that the pressure-resistance can be increased and the pressure resistance is high. Particularly preferred are spiral type modules or hollow fiber membrane modules. The spiral module has a basic structure in which an envelope-shaped membrane is wound around a porous core tube together with a net-shaped flow path material, and is widely known as a membrane separation module. The type of the hollow fiber membrane module is not particularly limited. However, it is preferable that the hollow fiber membrane module has a structure in which supply water and permeated water hardly cause drift, and clogging due to scale generation hardly occurs.

The reverse osmosis membrane used for the spiral type module is generally an asymmetric membrane or a composite membrane, but a composite membrane is particularly generally used. The composite membrane itself has a flat membrane shape and is composed of a porous support layer and a polymer homogeneous layer or a dense layer provided thereon.

Further, in order to further increase the strength of the support layer, it is preferable to provide a reinforcing layer such as a polyester woven fabric or a nonwoven fabric below the support layer. Preferred polymers for the porous support layer include polyesters, polyamides, polyolefins, polyacrylates, polytetrafluoroethylene, polysulfones, polycarbonates and the like, with polysulfone or polypropylene being particularly preferred.

Specific examples of the polymer homogeneous layer or dense layer formed on the porous support layer include a polyether-based composite membrane, an aromatic polyamide-based composite membrane, an aliphatic polyamide-based composite membrane, and an acetic acid asymmetric membrane. And polyethyleneimine-based and polyethylene oxide membranes. Among them, aromatic cross-linked polyamide with excellent desalination prevention performance even when water permeability is improved by thinning, and also high chemical resistance It is preferable to use In the case of an asymmetric membrane,
Practicality is high because the cellulose acetate membrane is excellent in separation performance, durability and chemical resistance.

As the membrane performance, the raw water pressure was 500 kPa,
Temperature 25 ° C, salt concentration (NaCl concentration) 500 in raw water
Under the condition of mg / l, the water permeability is at least 0.5 m ³ / m
² · day, preferably those salt rejection is at least 98% of the performance, and more preferably, water permeation rate 0.6 m ³ / m ²
It is preferable that the composition has a performance of 98.5% or more of salt rejection per day, more preferably 0.75 m ³ / m ² · day,
The salt rejection is 99% or more.

FIG. 1 shows a fresh water generating unit using a reverse osmosis membrane according to one embodiment of the present invention. In FIG.
The raw water taken in from the raw water line 1 is supplied to a head unit 2 directly connecting the filter unit 20 and the separation membrane unit 30.
From the filter unit 20. It is preferable to mount a check cone (not shown) of a type in which a polypropylene ball is pressed lightly with a spring, for example, as a backflow prevention mechanism at the inlet of the filter unit 20. Such non-return cones are commercially available inexpensively according to the pipe diameter.

Further, it is preferable that a similar check cone is attached to the permeated water outlet 10 and the concentrated water outlet 11 of the end plate 9 of the module container 7 accommodating the spiral type module 8 using the reverse osmosis membrane. Thereby, it is possible to prevent the liquid in the separation membrane unit 30 from leaking.

In the filter unit 20, the cartridge type filter element 3 is put in the storage container 4, and the storage container 4 is fitted to the head 2. As the raw water passes through the element 3, fine particles, suspended matter, bacteria, algae, and the like are filtered and removed. Further, by forming the element 3 as an activated carbon cartridge, in addition to filtering and removing fine particles, suspensions, bacteria, algae, and the like, organic substances, chlorine, color, odor, and dissolved gas in raw water can be absorbed and removed. Further, the head 2 is provided with a mounting port 5 and a relief valve (not shown) is provided here to cope with an abnormally high pressure of the raw water. A commercially available relief valve can be used.

The filtered water that has passed through the filter element 3 is supplied from the head 2 into the module container 7 and separated by a reverse osmosis membrane module 8 into a permeated water outlet 10 provided in the module container end plate 9. Therefore, the concentrated water flows out of the concentrated water outlet 11 provided in the end plate 9. It is preferable to attach a constant flow rate cone (not shown) made of vinyl chloride to the permeated water outlet 10 and the concentrated water outlet 11 as a constant flow rate mechanism. When the respective cones exceed a predetermined flow rate, the pressure loss, that is, the flow resistance,
By the elastic deformation of the cone, the flow path is suddenly narrowed, and the resistance is increased, suppressing the flow rate.
It is commercially available from the aforementioned non-return corn maker.

Further, as the operation is continued, the hindered substance may be deposited on the surface of the cartridge type filter element 3 as a scale. In such a case, the water pressure of the filtered water decreases, Since the performance of the reverse osmosis membrane module is reduced, the element 3 needs to be replaced. The storage container 4 is preferably transparent for checking the degree of contamination of the element 3 as a guide.

The filtration by the cartridge type filter element 3 is generally performed by filtering the whole amount of the supplied water. However, there is no problem even if so-called cross-flow filtration for discharging a part of the supplied water is performed. Also, if necessary, a flow control mechanism,
It is also possible to attach a pressure adjusting mechanism.

One end of the filter unit 20 having the above-described configuration and performance and one end of the module container 7 accommodating the reverse osmosis membrane module 8 constitute a common single member, that is, the head 2. The filter unit 20 and the separation membrane unit 30 (module container 7) are directly connected via the head 2 to each other. In the present embodiment, the filter unit 20 and the separation membrane module container 7 are directly connected coaxially.

As described above, the connecting portion is constituted by the head 2 made of a common single member, and the filter unit 20 and the separation membrane unit 30 are directly connected via the head 2 to form the whole fresh water producing unit. It is possible to reduce the size and weight. In addition, by sharing the head 2, the number of components can be reduced, and the manufacturing cost can be reduced. Furthermore, since the lightweight desalination unit is very easy to transport and install, it can quickly respond to emergency desalination and the like.

In the above embodiment, the filter unit 2
Although 0 and the separation membrane unit 30 are directly connected coaxially, they may be arranged in another positional relationship. For example, FIG.
As shown in FIG.
Through the filter unit 20 and the separation membrane unit 3
0 can be directly connected in parallel. With such a connection, the dimension in the vertical direction of the drawing (the longitudinal direction of the separation membrane unit 30) is reduced as compared with the embodiment shown in FIG. 1, and the size is reduced particularly in this direction. Further, the same effects as those of the embodiment shown in FIG. 1 can be obtained with respect to reduction in weight and manufacturing cost. The other parts in FIG. 2 are substantially the same as those in the embodiment shown in FIG. 1, and therefore, the description thereof will be omitted by retaining the same reference numerals as in FIG.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the case of the emergency fresh water generator shown in FIG. However, the present invention is not limited by this. This desalination machine was configured by employing the following for each member.

That is, in supplying raw water, it is necessary to pump up the raw water with an external pump and pressurize the raw water. Specifically, a portable engine pump for firefighting was used. The pump is a one-stage turbine pump using an air-cooled 4-cycle gasoline engine of 340 CC, output 15 PS, weight 65 kg, and maximum pump capacity is 0.7 MPa, 400 l / min. The set pressure of the relief valve was set to 0.7 MPa. As the filter element 3, a thread-wound type (made of polypropylene resin, filtration accuracy: 10 μm, 10-inch length) was used. The separation membrane module 8 used was one in which one spiral module (SUL-G10) having a separation membrane formed of a crosslinked aramid-based composite membrane and having an outer diameter of 4 inches was arranged. The container for housing the filter element was made of polypropylene resin, and the head portion of the filter unit and the head 2 serving as one cover plate of the separation membrane module container were processed with vinyl chloride. A unit formed integrally with the above members was defined as a fresh water producing unit.

When raw water was pressurized and supplied to the unit from the fire engine pump, the drinking water outlet 10
8m ³ / day of drinking water suitable for drinking and a concentrated water outlet 1
One to almost the same amount of miscellaneous water could be produced at the same time.

Further, since a constant flow cone made of vinyl chloride is attached to the permeated water outlet 10 and the concentrated water outlet 11 as the flow rate adjusting mechanism and the pressure adjusting mechanism, there is no need to adjust the flow rate and pressure, and handling is extremely difficult. In addition to being simplified, it can be made inexpensively and small. Also, after operation stop,
Even if the hoses of raw water, permeated water and concentrated water were removed, they did not leak out of the fresh water producing unit due to the action of the check cone.

[0033]

According to the present invention, in a fresh water producing unit using a filter unit and a separation membrane unit, a filter unit for filtering raw water and a separation membrane unit for separating a filtered liquid are provided via a common head. Since it is directly connected, it is very easy to handle, and a small and lightweight desalination unit can be manufactured at low cost.

When used as an emergency fresh water generator,
In preparation for fires or storms where drinking water or laundry water is not available for daily use, local governments such as municipalities, large hospitals,
Firefighting activities were completed by placing them in advance in disaster prevention water tanks, disaster prevention reservoirs, pools, etc. prepared by the company.
Or from an engine fire pump that does not fight fires,
Immediately, large quantities of high-quality drinking water (purified water) and domestic water (bath water and washing water) can be quickly produced from the water source in the affected area.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a fresh water generating unit according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a fresh water generating unit according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressurized raw water line 2, 22 Head 3 Filter element 4 Element storage container 5 Relief valve attachment port 7 Separation membrane (reverse osmosis membrane) module container 8 Separation membrane module 9 Module container end plate 10 Permeated water outlet 11 Concentrated water outlet 20 Filter Unit 30 Separation membrane unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B01D 71/16 B01D 71/16 71/52 71/52 71/56 71/56

Claims (14)

[Claims] 1. A filter unit for filtering raw water,
And a separation membrane unit for treating the water treated by the filter unit by using a separation membrane. The separation unit is directly connected to both of them through a common head. 2. The fresh water producing unit according to claim 1, wherein the filter unit and the separation membrane unit are directly connected coaxially. 3. The fresh water producing unit according to claim 1, wherein the filter unit and the separation membrane unit are directly connected in parallel. 4. The fresh water producing unit according to claim 1, wherein the filter unit has a built-in cartridge type filter element. 5. The fresh water generating unit according to claim 4, wherein said cartridge type filter element includes activated carbon. 6. The cartridge type filter element according to claim 4, wherein the cartridge type filter element is contained in a container which can see through the inside.
Or 5 desalination units. 7. The fresh water generating unit according to claim 1, wherein the separation membrane unit includes a spiral type module. 8. The method according to claim 1, wherein the separation membrane has a raw water pressure of 500 kPa,
At a temperature of 25 ° C. and a NaCl concentration of 500 mg / l in raw water, the water permeability is at least 0.5 m ³ / m ^2.
The fresh water generating unit according to any one of claims 1 to 7, which is a reverse osmosis membrane having a Cl exclusion rate of at least 98%. 9. The fresh water generating unit according to claim 8, wherein the reverse osmosis membrane is any one of a polyether-based composite membrane, an aromatic polyamide-based composite membrane, an aliphatic polyamide-based composite membrane, and a cellulose acetate-based asymmetric membrane. 10. The fresh water producing unit according to claim 1, wherein a relief valve is provided in the filter unit. 11. The fresh water generation unit according to claim 1, wherein a backflow prevention mechanism is provided at each of an inlet of the filter unit and an outlet of the separation membrane unit. 12. The fresh water generating unit according to claim 1, wherein a constant flow rate mechanism is provided at an outlet of the separation membrane unit. 13. The fresh water generating unit according to claim 1, which is used for emergency fresh water. 14. A fresh water producing method using the fresh water producing unit according to any one of claims 1 to 13.