JP2006015274A - Water treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water treatment apparatus constituted so as to sharply reduce the amount of air by intermittently diffusing air from an air diffusion pipe to reduce a maintenance control cost and capable of forming a turbulent flow in raw water (water to be treated) to effectively wash a membrane separator. <P>SOLUTION: In the water treatment apparatus composed of a raw water introducing means 1, a membrane separation tank 3 equipped with a plurality of membrane separators 5 and a plurality of air diffusion pipes 11, an air feeding equipment 16 for feeding air into the air diffusion pipes 11 and a treated water transfer pipe 7 connected to the membrane separators 5 to transfer treated water 4, the air feeding equipment 16 is equipped with an air changeover device 13. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water treatment apparatus that treats water, sewage, organic waste water, domestic waste water, and the like with a membrane.

  Conventionally, in water treatment using activated sludge for treatment of sewage, wastewater, etc., in order to obtain treated water, the activated sludge must be subjected to solid-liquid separation. Usually, the supernatant liquid is obtained by gravity sedimentation. In this case, a sedimentation basin having a sufficient sedimentation area and residence time is required to settle the activated sludge, and the water treatment device is enlarged and the installation volume is increased. It becomes a factor to cause. Moreover, when the sedimentation property of activated sludge deteriorates by bulking etc., sludge flows out from a sedimentation basin and causes the deterioration of treated water.

  In recent years, in the case of clean water, the use of so-called submerged membrane activated sludge process, which is superior in maintenance management and space saving, is increasing as an alternative to conventional coagulation sedimentation and sand filtration treatment, mainly in small-scale waterworks. I am doing. However, when water treatment is performed using membrane filtration, if the operation is continued, the membrane surface is caused by suspended substances and organic substances in the raw water introduced into the membrane filtration as membrane supply water. Alternatively, the pores become dirty with time and the amount of membrane filtration water decreases, or the transmembrane pressure difference increases. Usually, when the membrane surface or the inside of the pores becomes dirty, the membrane is periodically cleaned by a physical cleaning method. Examples of the physical cleaning method include reverse pressure water cleaning for backflow of membrane filtrate, flushing for watering the primary side of the membrane, and reverse pressure air cleaning for passing pressurized air from the secondary side of the membrane. And in order to remove a suspended substance from the water containing the suspended substance produced by washing | cleaning, coagulation sedimentation and sand filtration are performed.

  In general, a microfiltration membrane or an ultrafiltration membrane is used as a membrane for performing solid-liquid separation in such membrane filtration treatment. In order to apply a differential pressure to these separation (filtration) membranes, suction or pressurization by a pump is required. Usually, since the power of this type of pump is large, the running cost increases. In addition, a clear treated water free from suspended substances can be obtained by the separation membrane, but in order to prevent contamination of the separation membrane and to maintain a predetermined permeation flux, the separation membrane is periodically washed with medicine. There is a need.

  Furthermore, as a conventional water treatment device, a partition wall is provided between the filter bodies arranged in the membrane separation tank, and the sludge is introduced from the aeration tank, so that the filter bodies on both sides of the partition wall are regularly used. Discloses a treatment method in which filtration and aeration are alternately performed.

  In this type of treatment method, raw water (treated water) is introduced into a biological reaction tank for activated sludge treatment, and the sludge mixed solution after activated sludge treatment is immersed in a filtration module (membrane separator) consisting of multiple filter media. In the processing method of introducing into the filtration separation tank (membrane separation tank) to be installed, obtaining filtered water from the filtration module (membrane separator) with water head pressure, and returning the sludge mixed solution after filtration to the biological reaction tank, A partition wall is installed between the filtration modules (membrane separators) in the filtration / separation tank (membrane separation tank), and each aeration tube is provided at the bottom of each filtration module (membrane separator). In addition, it is characterized by alternately ventilating two adjacent diffuser tubes (see, for example, Patent Document 1).

  On the other hand, some conventional water treatment apparatuses sterilize inflow water flowing into a membrane separation tank. This sterilization treatment has an effect of preventing clogging of membrane equipment (separation membrane), and chlorination and ozone treatment are often used. In these sterilization treatments, the sterilizing action of chlorine and ozone continues to some extent even after the injection of chlorine and ozone into the influent water. Further, ultraviolet irradiation is also known as a means for sterilization.

  In conventional water treatment equipment that irradiates ultraviolet rays, ultraviolet rays are radiated to the upstream side of the circulation pump and the raw water supply part of the membrane module (membrane separator) through the filter and the concentrated circulating water that circulates through the circulation path. Then, an ultraviolet irradiation device for performing sterilization is provided. As a result, the raw water is sterilized by the ultraviolet irradiation device and then flows into the membrane module (membrane separator) and repeatedly sterilized by the ultraviolet irradiation device when circulating as concentrated circulating water (for example, Patent Documents). 2).

  However, this sterilization treatment by ultraviolet irradiation has a problem that the sterilization effect can be obtained only in the portion irradiated with ultraviolet rays, and the ultraviolet irradiation apparatus becomes large or complicated. Furthermore, in the case of clean water, since sterilization treatment with chlorine must be finally performed, sterilization treatment of inflow water flowing into the membrane treatment apparatus is usually performed by chlorine injection.

  In addition, titanium dioxide is used as a photocatalyst for sterilization in the conventional water treatment apparatus. This titanium dioxide is a non-toxic and inexpensive substance widely used as a white pigment, but when exposed to light, it produces a strong redox power and decomposes organic matter into carbon dioxide and water. In recent years, extensive research has been conducted on decomposing and detoxifying organic chemicals in water and air using this photocatalytic action. In this case, a titanium dioxide film is formed on a filter or porous silica gel with a large surface area. In contact with water.

JP 2003-305313 A (Solution for summary) JP-A-2002-1319 (page 2, right column, lines 16-24, and FIG. 1)

  In the conventional water treatment apparatus using the above-mentioned immersion membrane activated sludge method, the immersion membrane (separation membrane) is washed with air in order to prevent the immersion membrane (separation membrane) from being blocked (howling). Usually, air is continuously diffused from the lower part of the submerged membrane (separation membrane). The amount of air for this separation membrane cleaning is extremely large, for example, 30 times or more the inflow sewage amount. This is a drawback of the submerged membrane activated sludge method, and reducing the amount of air for cleaning the separation membrane is important for reducing the maintenance cost.

  In addition, in the treatment method in which multiple filtration bodies (membrane separators) are immersed and periodically filtered and diffused alternately, half of the filtration bodies (membrane separators) in the membrane separation tank always stop the filtration operation. Therefore, there is a problem that an effective amount of filtered water cannot be obtained and the filter body cannot be effectively used. In addition, when the continuous filtration time until washing is long, a sludge adhesion layer grows excessively on the surface of the filter body hit by the raw water (treated water) with a slow flow velocity, increasing the resistance of the sludge flow path, The flow of treated water) may be stagnant. This is a factor that causes a decrease in the permeation flux.

  In addition, organic substances and microorganisms contained in the raw water adhere to or multiply on the membrane surface to increase membrane filtration resistance and increase the frequency of chemical cleaning, which hinders maintenance management. The conventional solution to this problem, i.e., the method of injecting the flocculant into the raw water, may cause the flocculant itself to adhere to the membrane surface and inside the membrane when the agglomeration is insufficient, which may significantly increase the membrane filtration resistance. . In addition, the method using a chlorine agent is not preferable because when iron or manganese is contained in the inflowing water, these precipitate on the membrane surface and clog the membrane surface to significantly increase the membrane filtration resistance. Further, depending on the material of the separation membrane, an oxidizing agent such as chlorine or ozone may damage the separation membrane. Furthermore, if chlorine is used, some raw water may produce harmful organochlorine compounds.

  When sterilizing using photocatalytic action, the photocatalytic action is a surface action. For example, it is most efficient and preferable to use fine powder having a large specific surface area for titanium dioxide, for example. However, in the treatment with fine powder, it becomes difficult to separate the treated titanium dioxide powder from water. So far, a titanium dioxide thin film is formed on a plate filter or porous silica gel particles so that the titanium dioxide powder can be easily separated from water. However, if a large number of filters and silica gel particles are arranged and filled in order to obtain a large surface area in this way, light irradiation to the titanium dioxide thin film is hindered. Therefore, it is extremely difficult to achieve both water contact and light irradiation in order to increase sterilization efficiency.

  The present invention has been made to solve the above-described problems. The first object is to intermittently diffuse air from the air diffuser, thereby greatly reducing the amount of air and reducing maintenance costs. In addition, a water treatment apparatus capable of effectively washing the membrane separator by generating turbulent flow in the raw water (treated water) is obtained. The second object is to effectively prevent clogging of the separation membrane without adversely affecting the separation membrane, effectively using the membrane separator in the membrane separation tank, and high permeation flow. A water treatment apparatus is obtained in which a bundle is obtained and the size and the cost of equipment and treatment can be reduced. Furthermore, the third object is to effectively suppress clogging of the separation membrane by sterilizing microorganisms, efficiently decompose water containing organic substances, and hardly decomposed organic substances contained in raw water (treated water). The water treatment apparatus which can process is obtained.

  In the water treatment apparatus according to the present invention, the raw water introduction means, a membrane separation tank comprising a plurality of membrane separators and a plurality of air diffusion tubes, an air supply facility for supplying air to the air diffusion tubes, and a connection to the membrane separator And in the water treatment apparatus which consists of a treated water transfer pipe which conveys treated water, the above-mentioned air supply equipment is provided with an air changer.

  According to the present invention, when air is alternately supplied to two diffuser tubes by an air switch, the amount of air for cleaning the membrane separator can be halved. Further, when air is sequentially supplied to the three air diffusers, the amount of air can be reduced to 1/3 of the conventional one. Therefore, the maintenance cost can be greatly reduced. In addition, stable operation for a long period of time with a high membrane permeation flux is possible without performing reverse pressure water cleaning or chemical immersion cleaning.

  The present invention can prevent clogging of the air diffuser by providing a large opening at the lower part of the distal end portion of the air diffuser and making that portion into an inverted U shape. That is, even if sludge adheres to the inside of the air diffuser, the sludge can be allowed to flow out naturally to ensure the air balance of the entire air diffuser. This eliminates the need for a water washing facility for washing the air diffuser, eliminates the possibility of water flowing into the blower due to a valve failure, and eliminates the need for lifting the air diffuser and washing it. In addition, since there is no factor causing the uneven diffusion, the film processing itself is stabilized. Further, by dividing, for example, dividing the diffuser tube of a normal size installed in one membrane separator into three, it is possible to prevent the occurrence of a large air bias without changing the power.

  The present invention can prevent clogging of the separation membrane by providing air diffusion holes in the rotatable outer cylinder so that the air diffused from the inner cylinder partially concentrates and hits the separation membrane. Further, by providing the outer body with blades so that air diffuses, the outer body can be rotated by air diffusion without requiring new energy. In addition, when the shape of the diffuser tube is a triangular prism, and the diffuser holes are provided in a part of the ridge line of the triangular prism, the diffuser can be applied to the separation membrane with vigor. Furthermore, by providing a depression on each surface of the triangular prism, the diffuser tube can be rotated without providing a special power source. And clogging of the air diffuser can be effectively prevented by vigorously applying the air accumulated in the recess of the triangular prism to the separation membrane.

  According to the present invention, the clogging of the separation membrane can be prevented by providing a screw inside the diffuser tube and exhausting air partially and applying it to the separation membrane. In addition, by installing a piston inside the diffuser tube and moving this piston to block a part of the diffuser hole of the diffuser tube, it becomes possible to blow out the air from the remaining diffuser holes and hit the separation membrane. The clogging of the separation membrane can be prevented. That is, the piston in the air diffuser can be operated by interlocking the pneumatic actuator connected to the air diffuser, the compressor that sends compressed air to the actuator, and the three-way valve that distributes the compressed air.

  According to the present invention, it is possible to prevent sludge from accumulating inside the separation membrane by disposing the diffuser pipe in the separation membrane. Further, by installing and fixing the diffuser tube on the bottom surface of the membrane separation tank, it is possible to ensure the level of the diffuser tube and to uniformly apply the diffuser to the separation membrane.

  In the present invention, a pipe extending to the upper side of the water surface is connected to the air diffusion pipe, and an on-off valve is provided on the pipe above the water surface, and the on-off valve is normally closed and opened based on the state of the air diffusion. By so doing, sludge adhering to the air diffuser can be peeled off by sucking the raw water (treated water) into the air diffuser, and clogging of the air diffuser can be prevented.

  In the present invention, even after the membrane separator is immersed in the membrane separation tank, the membrane separator can be kept horizontal and the air diffused from the diffuser can be evenly applied to the membrane separator. In other words, in the past, when the accuracy of the finished dimensions of the bottom surface of the membrane separation tank was poor, it was difficult to install the platform horizontally, and the membrane separator had to be installed with the platform tilted, and the air diffused evenly. It was difficult to do. However, if the inclination of the submerged membrane separator is adjusted on the water surface so that the membrane separator can be kept horizontal, the finishing accuracy of the bottom surface of the membrane separation tank becomes unnecessary, and the membrane separator is installed. The membrane filtration efficiency can be kept high continuously by adjusting the inclination of the membrane separator while monitoring the state of the aeration afterwards.

  In this invention, titanium dioxide used as a photocatalyst in the membrane separation tank is a powder, and its reaction surface area is larger than that of granular particles and can be maintained at a high concentration, so that the treatment effect can be improved and stabilized. This makes it possible to treat difficult-to-decompose substances. Further, since an ultraviolet irradiator is used, sunlight is not required, and water treatment is possible even in a dark place or at night. And since titanium dioxide used as a photocatalyst becomes powder and always flows in the membrane separation tank, it is possible to apply ultraviolet rays uniformly and effectively.

  This invention divides the membrane separation tank into, for example, two parts by disposing an ultraviolet shielding plate in the membrane separation tank, immerses the membrane separator in one side, and immerses the ultraviolet irradiator in the other side. Can be prevented directly. Further, since a circulation flow is generated from the side where the membrane separation tank is present to the side where the ultraviolet irradiator is present due to the air lift effect, a conventional circulation pump is not required, and maintenance costs and equipment costs can be reduced.

  In the present invention, a carrier is put into a membrane separation tank, raw water (treated water) is flowed to hold microorganisms, and biological treatment capacity is improved. At the same time, the carrier flows in the membrane separation tank and collides with the separation membrane, thereby separating the membrane surface deposit attached to the separation membrane from the separation membrane. Furthermore, even if the suspended sludge concentration is low, treated water quality equivalent to or higher than that when the suspended sludge concentration is high can be obtained by increasing the amount of carrier added. The carrier is also effective for sludge retention as a countermeasure for low load. In addition, the load on the separation membrane can be reduced by attaching microorganisms to the carrier. Furthermore, there is an effect of removing environmental hormones and chromaticity by increasing the SRT of the sludge attached to the carrier. In addition, when the carrier is flowed for use in water treatment, a physical cleaning effect due to the collision of the carrier is obtained, and further, when activated carbon is added, a purification effect is obtained, and organisms are attached to the carrier. Therefore, it can be expected to reduce the load on the separation membrane. Moreover, the environmental hormone removal effect by SRT becoming long can also be expected.

  As described above, the present invention can reduce the required air amount by reducing the maintenance cost by providing the air switch to alternately diffuse the air from a plurality of air diffusers to the membrane separator. can do. In addition, stable operation for a long period of time with a high membrane permeation flux is possible without performing reverse pressure water cleaning or chemical immersion cleaning. Furthermore, by devising the structure and the installation position of the air diffuser and efficiently diffusing, raw water (treated water) can be treated efficiently. And by using a photocatalyst and an ultraviolet-ray, clogging of a separation membrane can be suppressed and the process of a hardly decomposable substance is attained.

Embodiment 1 FIG.
FIG. 1 is a flowchart showing a water treatment apparatus according to Embodiment 1 for carrying out the present invention. The water treatment apparatus according to Embodiment 1 includes a membrane separation tank 3 for treating raw water (treated water) 2 such as clean water, sewage, organic waste water, and domestic wastewater introduced from the raw water introduction means 1. The separation tank 3 enables biological treatment of the raw water (treated water) 2. The membrane separation tank 3 is provided with two submerged membrane separators 5 for solid-liquid separation of raw water (treated water) 2 into sludge and treated water 4 by a separation membrane 5a. A treated water tank 6 for storing treated water 4 treated by the membrane separator 5 is provided downstream of the membrane separation tank 3. The two membrane separators 5 are connected to the treated water tank 6 through the treated water transfer pipe 7 having branch portions 7a and 7b connected to them, and the treated water pump 8 and the flow meter 9 are connected to the treated water transfer pipe 7. Is arranged. In order to make the treated water 4 in the treated water tank 6 flow backward, the lower part of the treated water tank 6 and the treated water transfer pipe 7 are connected by the treated water suction pipe 10. In addition, if the edge part of the treated water transfer pipe 7 is arrange | positioned under the water surface of the treated water 4 in the treated water tank 6, the treated water suction pipe 10 does not need to be provided.

  In the water treatment apparatus according to Embodiment 1, a hollow fiber membrane is used as the separation membrane 5a of the membrane separator 5. The treated water pump 8 is a self-priming pump. The treated water pump 8 can also function as a backwash pump using a three-way valve, but it is preferable to use a positive pump having a mono pump or a rotary mechanism. The flow meter 9 can be an electromagnetic flow meter or an impeller flow meter.

  In the water treatment apparatus according to the first embodiment, two diffuser tubes 11 are arranged in the membrane separation tank 3 below the membrane separator 5 so as to correspond to the two membrane separators 5, respectively. The two air diffusers 11 are connected to an air switch 13 via pipes 12A and 12B, respectively. The air switch 13 is connected to a blower 15 via an air supply pipe 14, and these pipes 12A, 12B, air An air supply facility 16 is configured by the switch 13, the air supply pipe 14 and the blower 15. The treated water pump 8, the flow meter 9, the air switch 13 and the blower 15 are electrically connected to a control circuit (not shown).

  The air switch 13 is preferably a rotary valve 21 as shown in FIG. The rotary valve 21 includes a valve body housing part 22 in which the pipes 12A and 12B and the air supply pipe 14 are connected, a valve body 23 housed in the valve body housing part 22 in a rotatable manner, and the valve body 23 is driven to rotate. A driving device (not shown) such as a stepping motor can be used. The valve body accommodating part 22 and the valve body 23 of the rotary valve 21 can be spherical or cylindrical. In FIG. 2, the air supply pipe 14 is directed in a direction orthogonal to the paper surface for easy explanation.

  By using this air switch 13, the air supply from the blower 15 or the like communicates with at least one pipe 12 </ b> A or the pipe 12 </ b> B regardless of the rotational phase of the valve body 23. Overloading to the blower 15 can be prevented. Furthermore, by adjusting the size of the valve body 23, the ratio of the time for supplying air to only one of the diffuser tubes 11 connected to the ends of the pipes 12A and 12B and the time for supplying air to both of the diffuser tubes 11 Can be changed. This makes it possible to adjust the intensity of air diffusion to the separation membrane 5a with a single blower 15.

  Although it is most preferable to use the rotary valve 21 for the air switch 13, the rotary valve 21 is replaced with two electric cylinder valves 26A and 26B as shown in FIG. be able to.

  The switching timing of the air switch 13 is such that air is diffused intermittently from one air diffuser 11 or the other air diffuser 11, for example, every 2 to 60 seconds (with a cycle of 2 to 60 seconds). 5-20 seconds is recommended. For example, every 5 seconds means a state where air is diffused from one air diffuser 11 during the first 5 seconds and no air is diffused from the other air diffuser 11 during that time, and one air diffuser 11 is observed during the next 5 seconds. The air diffused from the other air diffuser tube 11 is stopped and the state of air diffused from the other air diffuser 11 is repeated. The same repetitive operation is performed in the case of 20 seconds or 60 seconds. However, it is also possible to control to diffuse at an appropriate time interval according to the quality of the raw water (treated water) 2 and the state of contamination of the membrane separator 5. In addition, depending on the structure of the valve body 23, the air diffuser 11 may be ventilated at the time of switching.

  In the normal operation of the water treatment apparatus according to the first embodiment, the operation of the treated water pump 8 generates a negative pressure in the separation membrane 5a of the membrane separator 5, and the raw water (treated water) 2 permeates the separation membrane 5a. Thus, treated water 4 is obtained. The treated water 4 flows into the treated water tank 6 through the treated water transfer pipe 7. During this time, air is ejected from the air diffuser 11 into the raw water (treated water) 2 as bubbles, and turbulent flow is generated in the raw water (treated water) 2 by the bubbles, and the water flow is converted into the membrane separator 5. The sludge that collides with the outer surface of the separation membrane 5a and adheres to the separation membrane 5a is peeled off by the shearing force of the water flow. Furthermore, the effect of peeling off the sludge adhering to the separation membrane 5a is strengthened by intermittently aeration from the diffusion tube 11 alternately. In the backwash operation, the treated water pump 8 rotates in the reverse direction, and the treated water 4 in the treated water tank 6 flows back to the membrane separator 5 through the treated water suction pipe 10 and the treated water transfer pipe 7. Thereby, the treated water 4 permeate | transmits the inside from the inside of the separation membrane 5a of the membrane separator 5, and the sludge adhering to the outer surface of the separation membrane 5a is peeled.

  As described above, in the water treatment apparatus according to the first embodiment, the two membrane separators 5 are washed by intermittently aeration from the two aeration pipes 11 using the air switch 13. The amount of air can be greatly reduced to about one-half of the conventional amount, thereby reducing the maintenance cost. Moreover, since the blower 15 serves as both provision of air for washing the membrane separator 5 and provision of air for biologically treating the raw water (treated water) 2, it can contribute to energy saving. Furthermore, turbulent flow can be generated in the raw water (treated water) 2 in the membrane separation tank 3 by intermittently aeration from the two diffusion tubes 11, and each membrane separator 5 can be effectively used. Can be washed. That is, in this Embodiment 1, since the hollow fiber membrane was used for the separation membrane 5a of the membrane separator 5, the replacement of the raw water (treated water) 2 between the hollow fiber membranes can be promoted, and the separation membrane 5a It is possible to prevent sludge concentration on the outer surface.

For example, when switching to the air diffuser 11 is performed at intervals of 5 seconds, the air switch 13 is normally operated over 1 million times in one year, and the normally used on-off valve operates without replacement for one year. It is impossible to make it happen. However, in the water treatment apparatus according to the first embodiment, since the rotary valve 21 is used for the air switch 13, in order to wash the membrane separator 5 by the conventional method of spraying from the air diffuser 11 to the treatment of 90 m ³ per day. The total amount of air used for 2 units required 80 m ³ / h, but the amount of air can be reduced by about 60% to about 30 m ³ / h with 2 units, contributing to energy saving. Maintenance costs can be reduced.

  In the water treatment apparatus according to the first embodiment, a hollow fiber membrane is used as the separation membrane 5a of the membrane separator 5, but a flat membrane can also be used. Even when a plurality of aeration equipment such as a horizontal hollow fiber membrane is used, a similar air switch 13 can be used. Furthermore, since the two diffuser tubes 11 are intermittently diffused, the raw water (treated water) 2 flows into the diffuser tubes 11 that are not diffused. This means that the diffuser tubes 11 are clogged with sludge. Helps to prevent. Further, although two diffuser tubes 11 are arranged for the two membrane separators 5, when the membrane separator 5 is composed of a plurality of separation membranes 5a, the diffused tube 11 is divided and the divided parts are divided. It is also possible to configure so that air is intermittently diffused. In this case, the same effect can be obtained.

Embodiment 2. FIG.
FIG. 4 is a flowchart showing a water treatment apparatus according to Embodiment 2 for carrying out the present invention. The same parts as those in FIG. In the water treatment apparatus according to the second embodiment, three membrane separators 5 are installed in a membrane separation tank 3 in which raw water (treated water) 2 is stored. In the water treatment apparatus of the second embodiment, a flat membrane is used as the separation membrane 5a of the membrane separator 5. Therefore, the membrane separator 5 is connected to the treated water tank 6 through the treated water transfer pipe 7 having the branch portions 7a, 7b, 7c connected to them.

  In the water treatment apparatus according to the second embodiment, three diffuser tubes 11 are arranged below the three membrane separators 5 in the membrane separation tank 3. These three diffuser tubes 11 are connected to one air switch 13 via pipes 12A, 12B, and 12C, and this air switch 13 is connected to the blower 15 via an air supply pipe. The control circuit is provided with a function of controlling the air switch 13 so as to control the amount of air from the blower 15 that is alternately ejected from any one of the three diffuser tubes 11.

  For example, a rotary valve 27 as shown in FIG. 5 is preferably used for the air switch 13 in the second embodiment. The rotary valve 27 includes a valve body housing portion 28 in which the pipes 12A, 12B, 12C and the air supply pipe 14 are connected, a valve body 29 rotatably housed in the valve body housing portion 28, and the valve body 29 rotating. It can comprise a drive device for driving. However, this rotary valve 27 can also be replaced with three electric cylinder valves 30A, 30B, 30C as shown in FIG. The shape of the rotary valve 27 may be any structure that smoothly switches the aeration to the pipes 12A, 12B, and 12C.

  The switching timing of the air switch 13 according to the second embodiment is determined intermittently, for example, every 2 to 60 seconds, for example, every 2 to 60 seconds. I am trying to control it. For example, 5 second switching means that during the first 5 seconds, the air diffused from one air diffuser 11 is not diffused from the remaining two air diffusers 11 and the next 5 seconds. Air diffused from one of the remaining two air diffusers 11 and no air diffused from the remaining two air diffusers 11 and the remaining air that was not diffused in the next 5 seconds The air diffused from the one air diffuser tube 11 and the air diffused from the remaining two air diffuser tubes 11 are repeated. Also in the case of the second embodiment, it is possible to operate at other time intervals depending on the quality of the raw water (treated water) 2 and the state of contamination of the membrane separator 5.

  In the second embodiment, when the three membrane separators 5 are installed by intermittently diffusing air from the three diffusing pipes 11 by using the air switch 13, when cleaning them. The amount of air can be significantly reduced to about one-third of the conventional amount, and maintenance costs can be reduced. Further, by intermittently aeration from the three diffusion tubes 11, turbulent flow can be generated in the raw water (treated water) 2 in the membrane separation tank 3, and the separation membrane of each membrane separator 5 5a can be washed effectively.

  In the second embodiment, a flat membrane is used as the separation membrane 5a of the membrane separator 5. However, when a hollow fiber membrane is used instead of the flat membrane, the raw water between the three hollow fiber membranes ( The replacement of the water 2 to be treated can be promoted, and sludge concentration can be prevented from occurring on the outer surface of the separation membrane 5a. Further, although three diffuser tubes 11 are arranged for the three membrane separators 5, when the membrane separator 5 is composed of a plurality of separation membranes 5a, the diffused tube 11 is divided and the divided parts are divided. It is also possible to configure so that air is intermittently diffused. In this case, the same effect can be obtained.

Embodiment 3 FIG.
FIG. 7 is a flowchart of the water treatment apparatus according to Embodiment 3 for carrying out the present invention. The same parts as those in FIG. In the water treatment apparatus according to the third embodiment, a reaction tank 31 for storing raw water (treated water) 2 is provided, and the reaction tank 31 is divided into an oxygen-free tank 33 and a membrane separation tank (aerobic tank) 34 by a partition wall 32. It is divided into The anaerobic tank 33 is provided with a stirrer 35 and serves as a tank for removing BOD (biochemical oxygen demand) and nitrogen. In the membrane separation tank (aerobic tank) 34, two membrane separators 5 similar to those in the first embodiment are installed. An opening 32 a is provided in the lower part of the partition wall 32, and an overflow dam (not shown) is provided in the upper part of the partition wall 32. Then, one end of new pipes 7 c and 7 d is connected to the branch portions 7 a and 7 b of the treated water transfer pipe 7, the other end is connected to the lower part of the membrane separator 5, and the treated water 4 is placed above and below the membrane separator 5. It is obtained from two places. In addition, the rotary valve 21 and two electric cylinder valves 26A and 26B similar to the first embodiment can be used for the air switch 13.

  In the water treatment apparatus according to the third embodiment, a fine screen 36 is disposed in the raw water introduction means 1 to prevent foreign substances from entering the reaction tank 31 and the separation membrane 5a of the membrane separator 5 is contaminated. To prevent clogging. The water treatment apparatus also includes a flocculant addition facility 37 for adding a flocculant for removing phosphorus to a membrane separation tank (aerobic tank) 34, and a treatment that flows through the treated water transfer pipe 7 during backwashing. A chemical solution addition facility 38 for adding a chemical solution to the water 4 and pressure gauges 39A and 39B for detecting the filtration pressure of the separation membrane 5a of the membrane separator 5, that is, the membrane differential pressure, are provided. These pressure gauges 39A and 39B are provided in the treated water transfer pipe 7, respectively. The screen width of the screen 36 can be selected from 1 mm, 0.8 mm, 0.5 mm, or less depending on the application such as clean water or sewage. The screen 36 can be replaced with an auto strainer.

The chemical solution addition equipment 38 is configured to naturally flow a chemical solution for disinfection such as sodium hypochlorite. Although not shown, a chemical solution tank that stores the chemical solution and a chemical solution in the chemical solution tank 7 are disposed in the treated water transfer pipe 7. There is no need for a chemical-resistant chemical liquid pump that is composed of an advection pipe that causes the chemical liquid to flow and an on-off valve disposed in the advection pipe. The chemical solution addition equipment 38 can be configured to flow the chemical solution down to the membrane separation tank 34. The on-off valve of the chemical solution addition equipment 38 is a solenoid valve, and this solenoid valve is electrically connected to the control circuit. The on-off valve may be manually operated. The control circuit includes the difference between the liquid level of the chemical liquid in the chemical liquid tank and the water level of the raw water (treated water) 2 in the reaction tank 31, the diameter and length of the advection pipe and the treated water transfer pipe 7, and pressure gauges 39A and 39B. The open / close time of the on-off valve, that is, the amount of the chemical liquid flowing out from the chemical tank is automatically controlled in consideration of the detected value of the above.
Needless to say, when the chemical solution is not injected by natural flow, the chemical solution can be injected into the treated water transfer pipe 7 by the chemical pump.

  In the normal operation of the water treatment apparatus according to the third embodiment, the water level of the raw water (treated water) 2 in the membrane separation tank 34 rises due to the diffusing air from the diffusing pipe 11, and the raw water (treated water) 2 Due to the air lift effect that flows over the partition wall 32 and flows into the oxygen-free tank 33, the raw water (treated water) 2 becomes a downward flow in the oxygen-free tank 33 and passes through the opening 32 a below the partition wall 32 for membrane separation. It returns to the tank 34 and a circulating flow of raw water (treated water) 2 is generated. When the raw water (treated water) 2 is treated in this way, sludge continues to adhere to the front and back surfaces of the separation membrane 5a of the membrane separator 5 over time, and the pressure values of the pressure gauges 39A and 39B However, the turbulent flow is generated in the raw water (treated water) 2 due to the alternate air diffused from the air diffuser 11, and the shear force of the water flow causes the sludge adhering to the surface of the separation membrane 5a to be peeled off. Therefore, it is possible to delay the increase in the membrane differential pressure.

  However, sludge gradually accumulates on the surface of the separation membrane 5a due to the turbulent flow generated by the alternate aeration. Therefore, when the pressure values of the pressure gauges 39A and 39B exceed a predetermined value, the backwash operation is started. Thereafter, the normal operation and the backwash operation are repeated, and if the pressure value still does not recover, the on / off valve of the chemical solution addition equipment 38 is opened, and the chemical solution injection cleaning is automatically performed.

  When the membrane separator 5 is back-washed, when the treated water pump 8 that can be fed back is diffused from the diffuser tube 11, the treated water pump 8 is rotated in the reverse direction, and the inside of the treated water tank 6 The treated water 4 is sent back to the membrane separator 5. Normally, backwashing is performed about once every 10 minutes while maintaining the discharge amount of the treated water pump 8 at 1.5Q. However, the two treated water pumps 8 can be operated, the discharge amount can be 3Q, and the backwash can be performed once every 30 minutes. And in the case of clean water, it is preferable to carry out about once every 10 minutes while injecting the chemical solution from the chemical solution addition equipment 38. Thus, by backwashing with the treated water 4, it is possible to prevent the unevenness of air due to the sludge adhering to the separation membrane 5 a of the membrane separator 5. In the case of sewage or the like, backwashing with treated water 4 into which a chemical solution has been injected is performed about once a week. Every time backwashing, several hundred mg / L of chemical solution is intermittently injected into 1 liter of treated water 4. However, the chemical solution can be continuously injected according to the degree of contamination of the membrane separator 5.

  Note that the pull-up cleaning, in which the membrane separator 5 is lifted and cleaned, includes a pressure gauge 39A, when the membrane pressure difference of the separation membrane 5a of the membrane separator 5 increases, or when the suction pressure of the treated water pump 8 reaches a predetermined value. This is performed when 39B reaches a predetermined value, but is usually performed once or twice a year. In any case, first, the operation of the treated water pump 8 is stopped, the membrane separator 5 is pulled up from the raw water (treated water) 2, and the chemical solution in the immersion tank provided separately from the reaction tank 31 is 3 Soak for ~ 4 hours. Sodium hypochlorite having a concentration of about 1000 to 2000 mg / L is used for the chemical solution. This pull-up cleaning is preferably performed automatically at a constant cycle using a timer or based on the indicated values of the pressure gauges 39A and 39B.

  As described above, in the water treatment apparatus according to the third embodiment, not only the air diffuser 11 alternately diffuses, but also the optimal cleaning is performed in conjunction with the set values of the pressure gauges 39A and 39B. The filtration pressure of the separator 5 can be automatically reduced, and the work of lifting the membrane separator 5 and washing it can be reduced. Further, since the treated water 4 is pushed out from the inside of the separation membrane 5a of the membrane separator 5 by the treated water pump 8, not only the surface of the separation membrane 5a can be removed but also the inside of the separation membrane 5a. Can also be pushed out. Furthermore, since the treated water 4 is pushed out from the inside of the separation membrane 5a, the entire separation membrane 5a can be reliably washed regardless of whether or not the air diffused from the diffuser tube 11 hits the separation membrane 5a. And since a chemical | medical solution is inject | poured into the treated water 4 from the chemical | medical solution addition equipment 38, the scale-like dirt which cannot be removed only with the treated water 4 can be dissolved, and the inside and outside of the separation membrane 5a can be cleaned. In addition, since the cleaning is automatically performed according to the contamination of the separation membrane 5a, the frequency of cleaning becomes efficient and the maintenance is facilitated. And the operation | work which raises the membrane separator 5 also decreases. In addition, if the state is maintained for several minutes after the chemical solution is injected, the effect of the chemical solution is further improved, so that maintenance cleaning can be performed by selecting the injection frequency of the chemical solution.

  In addition, when the membrane separator 5 is conventionally used for biological treatment using activated sludge or the like, a low concentration chemical solution is accommodated in the chemical solution tank so as not to adversely affect the activated sludge during chemical cleaning, Since the chemical tank is enlarged and it is necessary to store a predetermined amount of chemical liquid at a predetermined concentration in the chemical tank, maintenance management is complicated. However, in the water treatment apparatus according to Embodiment 3, sodium hypochlorite is used. Since the chemical liquid such as chlorine is allowed to flow down naturally, the conventional backwash pump is not required, the chemical tank is made smaller, the chemical-resistant chemical pump is omitted, and the chemical liquid has a predetermined concentration. Therefore, it is possible to save the time and effort for adjustment, and it is possible to reduce installation space, equipment cost, operation cost, and the like. Since the chemical solution is allowed to flow naturally based on the difference in water level, the amount of the chemical solution flowing back to the membrane separation tank (aerobic tank) 34 is reduced, and the recovery rate of sludge adhering to the separation membrane 5a is also improved. To do. In addition, since the on-off valve is automatically controlled, maintenance is facilitated.

  When the activated sludge concentration (MLSS) is high, for example, about 10000 ppm, the separation membrane 5a of the membrane separator 5 is likely to be clogged, so that the activated sludge concentration is preferably maintained at 5000 to 6000 ppm. At this time, the activated sludge concentration can be adjusted by a drawing valve (not shown) provided in the reaction tank 31 so that the raw water (treated water) 2 in the reaction tank 31 can be drawn. Also, if treated water 4 is taken from treated water tank 6 and ozone is added thereto to prepare ozone treated water, and the ozone treated water is allowed to flow to membrane separator 5 during backwashing, it is effective in reducing sludge volume. There is. In preparation for a large change in the amount of raw water (treated water) 2 due to rain or the like, two treated water pumps 8 are provided, and they can be moved simultaneously to double the suction force. it can.

  Although not shown, a draft tube is provided in the oxygen-free tank 33 of the reaction tank 31, and raw water or return sludge is introduced into the draft tube, so that the oxygen-free tank 33 and the membrane separation tank (aerobic) in the reaction tank 31 are introduced. A circulation flow can be generated in the (tank) 34, and the dead space in the reaction tank 31 can be eliminated. In this case, if a stirring blade is provided in the draft tube, a circulating flow can be generated efficiently. Further, if the discharge side of the draft tube is tapered, the flow rate can be increased and the stirring efficiency can be improved. Furthermore, if the draft tube is configured to move up and down by a float, a circulating flow corresponding to the water level can be generated. Further, by providing blades outside the draft tube, the draft tube can be rotated by the circulating flow, and the stirring efficiency can be further improved. Further, even if a draft pipe is provided in the draft tube and the circulation flow is applied to a position where a dead space is likely to occur, the processing efficiency can be improved.

The operation conditions of the water treatment apparatus in Embodiment 3 are as follows: the pore diameter of the separation membrane 5a of the membrane separator 5 is 0.1 μm, the area of the separation membrane 5a is 46 m ² , and the flocculant addition equipment 37 is added for phosphorus removal. The product was an aluminum flocculant, the average sludge concentration in the membrane separation tank (aerobic tank) 34 was 10,000 mg / L, and the average membrane filtration flux was 0.7 m ³ / m ² · d. And the air quantity from the blower 15 was 30 m < ³ > / h, and intermittent air diffused alternately with respect to the two membrane separators 5 from the two air diffusers 11 every 10 seconds. Furthermore, after performing suction filtration for 9 minutes, the suction filtration was stopped for 1 minute, and only aeration cleaning was performed. As a result, the amount of air for cleaning could be reduced by 60% in the water treatment apparatus of Embodiment 3 as compared with continuous aeration supplied continuously to the two membrane separators 5 respectively. In addition, the daily average membrane filtration flux can be kept as high as 0.75 to 0.85 m ³ / m ² · d without performing reverse pressure cleaning or chemical immersion cleaning, and the membrane differential pressure is set to 20 kPa or less. It was possible to drive stably for a long time. In addition, as a cleaning operation of the separation membrane 5a, an operation of back pressure cleaning for 30 seconds / 10 minutes without pulling for 1 minute but 9 minutes was also performed. The solenoid valve switching time for back pressure cleaning is (15 + 15) seconds / 10 minutes. After all, even in this washing operation, water treatment could be performed stably for a long time.

Embodiment 4 FIG.
FIG. 8 is a flowchart showing a water treatment apparatus according to Embodiment 4 for carrying out the present invention. The same parts as those in FIG. The water treatment apparatus according to the fourth embodiment is based on the water treatment apparatus according to the first embodiment, and a hollow fiber membrane is used for the separation membrane 5a of the membrane separator 5. However, in the water treatment apparatus according to the fourth embodiment, the photocatalyst 41 made of powdered titanium dioxide is movably added to the membrane separation tank 3. In the membrane separation tank 3, an ultraviolet irradiator 42 such as an ultraviolet lamp for irradiating the photocatalyst 41 with ultraviolet rays, and the ultraviolet rays from the ultraviolet irradiator 42 directly hit the separation membrane 5 a of the membrane separator 5, so that they deteriorate. A flat-shaped ultraviolet shielding plate 43 is provided to prevent this.

  In the fourth embodiment, since the ultraviolet shielding plate 43 is provided in the membrane separation tank 3, an air lift effect is generated when the membrane separator 5 is cleaned by being diffused from the air diffuser 11, and the ultraviolet shielding plate 43 is interposed therebetween. The water level of the raw water (treated water) 2 is increased on the membrane separator 5 side, and a water level difference is generated between the raw water (treated water) 2 on the ultraviolet irradiator 42 side, and the raw water ( A circulation flow of water 2) is generated. For this reason, ultraviolet rays hit the photocatalyst 41 satisfactorily, sterilizing microorganisms, thereby effectively suppressing clogging of the separation membrane 5a, effectively decomposing the raw water (treated water) 2 containing organic matter, Treatment water) 2 can also treat the hardly decomposable organic matter contained in the water. Moreover, since the raw water (treated water) 2 can be circulated by the air lift effect, a circulation pump is not required, and installation costs and maintenance costs are reduced. In addition, the same effect as in the first embodiment can be obtained.

  That is, since two membrane separators 5 are installed in the membrane separation tank 3 and air is intermittently diffused from the diffuser tube 11 using the air switch 13, the separation membrane 5a of the membrane separator 5 is washed. The amount of air at the time can be greatly reduced, and maintenance costs can be reduced. Moreover, since the turbulent flow can be generated in the raw water (treated water) 2 in the membrane separation tank 3 by intermittently diffusing from the diffuser tube 11, the raw water (treated water) between the hollow fiber membranes. 2 can be promoted, and the separation membrane 5a of the membrane separator 5 can be effectively washed. In addition, when the air diffuser 11 intermittently diffuses, the photocatalyst 41 attached to the separation membrane 5a is peeled off from the separation membrane 5a and effectively works as the photocatalyst 41 again. Further, by using the photocatalyst 41 and the ultraviolet irradiator 42, clogging of the separation membrane 5a can be suppressed due to the effects of decomposition and sterilization of organic matter, and agricultural chemicals (for example, MEP, ipconazole), dyes (for example, orange) 205, green 201), and environmentally difficult substances such as environmental hormones (for example, octylphenol) can be treated.

  In the water treatment apparatus according to the fourth embodiment, titanium dioxide is used as the photocatalyst 41, but zinc oxide, zirconium oxide, or tungsten oxide can be used instead. The installation position of the ultraviolet shielding plate 43 may be near the ultraviolet irradiator 42 or the membrane separator 5. Further, even when a further membrane separator 5 is added to the two membrane separators 5, the air switch 13 is arranged in the air supply pipe 14 from the blower 15, and the air is intermittently ejected. Effects can be obtained. Then, although the flat ultraviolet shielding plate 43 is used, the semicylindrical ultraviolet shielding plate 43A as shown in FIG. 9A or the semi-cubic ultraviolet shielding plate 43B as shown in FIG. 9B. Can be used. When these ultraviolet shielding plate 43A or ultraviolet shielding plate 43B is used, a stirring flow is generated in the vicinity of the ultraviolet irradiator 42, so that the processing efficiency is improved as in the case where the flat ultraviolet shielding plate 43 is used. .

Embodiment 5. FIG.
FIG. 10 is a flowchart of the water treatment apparatus according to Embodiment 5 for carrying out the present invention. The same parts as those in FIG. This water treatment apparatus is based on the water treatment apparatus in the above-described third embodiment, and a disinfection tank 51 is installed in the subsequent stage of the treatment water tank 6. The sterilization tank 51 also serves to clean the membrane separator 5 pulled up from the membrane separation tank 3. The effective water depth of the sterilization tank 51 is set to a depth at which the membrane separator 5 can be completely immersed, for example, 2.2 m. An inflow port 52 through which the treated water 4 flows from the treated water tank 6 is formed on one side wall 51 a of the disinfection tank 51. On the other side wall 51b of the sterilization tank 51, an overflow weir 53 is formed to allow the treated water 4 after sterilization to overflow into a river, a middle water storage tank or the like. At one corner of the bottom wall 51c of the sterilization tank 51, a pot place 54 for rapidly discharging the waste water that has washed the membrane separator 5 in the sterilization tank 51 is formed to be lower. And in the disinfection tank 51, the wall board 55 for partitioning the inside of the disinfection tank 51 into the front | former stage (upstream) and the back | latter stage (downstream) is installed so that removal is possible.

  In a normal disinfection process, the wall plate 55 is attached to the disinfection tank 51, and a gap 56 is left between the lower end portion 55 a of the wall plate 55 and the bottom wall 51 c of the disinfection tank 51. As a result, the treated water 4 flowing from the treated water tank 6 becomes a downward flow at the front stage of the wall plate 55, passes through the gap 56 below the wall plate 55, and becomes an upward flow at the rear stage of the wall plate 55. Therefore, the flow path of the treated water 4 becomes long, and the treated water 4 and the disinfectant are mixed well. On the other hand, when the membrane separator 5 pulled up from the membrane separation tank 3 is washed, the wall plate 55 is removed from the disinfection tank 51. Then, a drainage pump (not shown) is temporarily installed in the pot place 54 of the sterilization tank 51, the water level in the sterilization tank 51 is lowered so that sewage does not overflow, and the membrane separator 5 is immersed in the sterilization tank 51.

  In the water treatment apparatus according to the fifth embodiment, the disinfection tank 51 is used to wash the membrane separator 5, so that it is necessary to install a dedicated washing tank or FRP which has been necessary in spite of its low frequency of use. It is not necessary to prepare a cleaning tank made of (glass fiber reinforced plastic), and the installation area is reduced. Further, since the gap 56 is left between the lower end portion 55a of the wall plate 55 and the bottom wall 51c of the disinfection tank 51, the flow path of the treated water 4 can be lengthened. Therefore, mixing of the treated water 4 and the disinfectant can be promoted and the disinfection time can be extended. And since the treated water 4 remains in the disinfection tank 51, the time required for supplying the water, which has been conventionally required, becomes unnecessary, and the time required for cleaning the membrane separator 5 can be shortened.

Embodiment 6 FIG.
11 and 12 are partial cross-sectional views showing a water treatment apparatus according to Embodiment 6 for carrying out the present invention. The same parts as those in FIG. In the water treatment apparatus according to the sixth embodiment, the membrane separator 5 can be easily pulled out of the membrane separation tank 3. That is, the membrane separation tank 3 is provided with, for example, a pair of guide rails 61 for guiding the membrane separator 5 and a lifting device 62 for lifting the membrane separator 5. Each guide rail 61 has a substantially inverted L shape, and a vertical portion 61a extending vertically from the bottom wall 3b of the membrane separation tank 3 between the one side wall 3a of the membrane separation tank 3 and the membrane separator 5, and a membrane The upper end surface of one side wall 3a of the separation tank 3 is configured by a horizontal portion 61b that horizontally extends laterally, and an arc portion 61c that smoothly connects the vertical portion 61a and the horizontal portion 61b. . The pair of guide rails 61 are preferably arranged on the side edge side of the membrane separator 5 so as not to prevent the raw water (treated water) 2 from flowing into the separation membrane 5a of the membrane separator 5. The pulling equipment 62 is provided with a hooked wire 63 for connecting the membrane separator 5 using hydraulic pressure.

  When pulling up the membrane separator 5 from the membrane separation tank 3, the tip of the wire 63 of the pulling equipment 62 is connected to the membrane separator 5 and the pulling equipment 62 is operated. Thereby, as shown in FIG. 12, the membrane separator 5 moves upward along the vertical portion 61a of the guide rail 61, and then smoothly changes the direction along the arc portion 61c in the horizontal direction, and the horizontal portion 61b. Move horizontally. Thus, in the water treatment apparatus according to the sixth embodiment, the membrane separator 5 can be easily pulled up by the guide rail 61 and the lifting equipment 62. Further, compared to the conventional chain lock structure in which the lifting equipment is installed above the membrane separator 5 and the membrane separator 5 is lifted only upward, there is no need to install the lifting equipment above the ceiling, The height can be reduced.

  As mentioned above, in the water treatment apparatus in Embodiments 1-6 for implementing this invention, the amount of air is reduced to less than half of the conventional by using the conventional diffuser tube 11 and using the air switch 13. FIG. The sludge adhering to the membrane separator 5 can be effectively separated, but the structure and arrangement of the air diffuser 11 and the membrane separator 5 are devised as described below. In addition, the sludge adhering to the membrane separator 5 can be peeled off more satisfactorily by feeding the carrier. In the following description, the same parts as those in FIG.

  The air diffuser 71 as the first example shown in FIG. 13 is configured so as not to clog itself. That is, the diffuser pipe 71 connected to the branch pipe 12 is constituted by a cylindrical diffuser pipe body 73 having a plurality of diffuser holes 72 and a cap 74 fitted to the tip of the diffuser pipe body 73. A large opening 75 is provided in the lower surface on the distal end side of the diffuser tube main body 73 so that the sludge flowing into the diffuser tube main body 73 can be easily discharged. Then, in order to ensure the overall air balance of the air diffuser 71, a box-shaped frame wall 76 surrounding the open port 75 is projected downward from the open port 75, and the portion has an inverted U-shaped cross section. The inside of the wall 76 is an air chamber.

  Thereby, even if sludge adheres to the inside of the diffuser pipe 71, the sludge can be naturally discharged into the raw water (treated water) 2 from the open port 75. In addition, if this air diffuser 71 is used, a dedicated water washing facility for washing the air diffuser 71 becomes unnecessary, and the trouble of lifting the air diffuser 71 and washing it can be saved. Furthermore, since this air diffuser 71 does not cause an uneven air diffuser, the sludge adhering to the membrane separator 5 can be stably peeled off. Conventionally, since the air pipe and the water washing pipe are connected by a valve, water flows into the blower 15 when the valve breaks down. However, if this air diffuser 71 is used, there is no need for water washing. There is no need to install a cleaning tube. Further, it is possible to eliminate the flow of water into the blower 15 due to the failure of the conventional valve. If the diffuser tube 71 is divided into, for example, three for one membrane separator 5, a large bias of diffuser can be prevented without changing the power.

  A diffuser pipe 81 as a second example shown in FIGS. 14 to 16 is rotatable so as to surround a cylindrical inner cylinder 82 connected to the blower 15 via the air supply pipe 14 and the entire inner cylinder 82. A cylindrical outer cylinder 83 provided on the outer surface is provided. One end of the outer body 83 is rotatably supported by the bearing 84, and the other end is rotatably supported by the end of the air supply pipe 14. A slit 82a is formed on the upper surface side of the inner cylinder 82 in a direction along the axis, and air is ejected upward from the slit 82a. A large number of diffuser holes 83a are formed in the outer cylinder 83 along a spiral line. A plurality of blades 85 are provided at equal intervals on one end of the outer peripheral surface of the outer body 83, and an air diffuser 14 a for ejecting air toward the blades 85 of the outer body 83 is provided in the air supply pipe 14. It is.

  In this air diffuser 81, the air from the blower 15 flows into the inner cylinder 82 through the air supply pipe 14, and goes upward through the slit 82a. In the meantime, as shown in FIG. 16, air is also ejected from the air diffuser 14 a of the air supply pipe 14, the air generates an upward flow in the raw water (treated water) 2, and the upward flow hits the blade 85. The outer cylinder 83 is rotated. When the diffuser holes 83a of the outer cylinder 83 are aligned with the slits 82a of the inner cylinder 82a, the air is partially concentrated and ejected from the diffuser holes 83a toward the membrane separator 5. At this time, since the plurality of air holes 83a are provided along the spiral line, the position of the air diffuser holes 83a moves in the horizontal direction, and the water flow hits the entire membrane separator 5. In addition, since the aeration position moves, the aeration can be partially concentrated on the membrane separator 5 and vigorously applied, and clogging of the membrane separator 5 can be efficiently prevented.

  A diffuser tube 91 as a third example shown in FIGS. 17 to 19 includes a triangular prism-shaped diffuser tube main body 92. A shaft portion 93 is integrally provided at one end of the air diffuser main body 92, and the shaft portion 93 is rotatably supported by a bearing (not shown). The other end of the air diffuser main body 92 is rotatably supported by a part of the air supply pipe 14 connected to the blower 15. The three ridgelines 92b formed by the three side walls 92a of the diffuser tube main body 92 are provided with a diffuser hole group 94 including a plurality of diffuser holes. These diffused hole groups 94 are formed at positions shifted from each other with respect to the three ridgelines 92b. Further, the three side walls 92a of the air diffuser main body 92 are provided with, for example, semicircular concave grooves 95 that are long in the axial direction. The concave groove 95 is provided so as to be offset toward the one ridgeline 92b, and the surface area of the same side of the side wall 92a is increased. Then, another diffuser tube 96 is connected to the branch portion 14a of the air supply tube 14 below the diffuser tube body 92, and the air blown from the diffuser tube 96 is applied to the concave groove 95 of the diffuser tube body 92 to rotate. I am trying to make it.

  In such an air diffuser 91, the air that has flowed into the air diffuser main body 92 is mainly partially ejected toward the membrane separator 5 from the air diffuser group 94 located above. In the meantime, as shown in FIG. 19, the air ejected from another diffuser tube 96 hits the side wall 92a of the diffuser tube main body 92. Since the side surface 92a has a large surface area on one side having the concave groove 95, the diffuser tube main body 92 Rotates in one direction, and the air accumulated in the concave groove 95 moves vigorously upward and strikes the membrane separator 5 strongly. Further, when the air diffuser main body 92 rotates, the position of the air diffuser holes 94 moves in the horizontal direction. Thereby, the diffuser tube main body 92 can be rotated without requiring a special power source, and the diffuser is partially concentrated on the membrane separator 5 while moving the position of the diffuser hole group 94. This can be applied well, and clogging of the membrane separator 5 can be efficiently prevented.

  A diffuser tube 101 as a fourth example shown in FIG. 20 includes a cylindrical diffuser tube body 102 with one end closed, and a plurality of diffuser holes 102a are formed in the diffuser tube body 102 along a spiral line. It is. A support shaft 103 is provided at one end of the diffuser tube main body 102, and this support shaft 103 is rotatably supported by a bearing 104. The other end of the air diffuser main body 102 is closed by a cap 105, and the air supply pipe 14 from the blower 15 is passed through the cap 105, and the cap 105 is rotatable with the air diffuser main body 102. A screw blade 106 protruding inward is provided on the inner peripheral surface of the diffuser tube main body 102.

  In the air diffuser 101, the air from the blower 15 is ejected into the air diffuser main body 102 through the air supply pipe 14. The air jetted into the diffuser tube body 102 hits the screw blades 106 and rotates the diffuser tube body 102. During this time, the air is ejected to the outside from the diffuser holes 102a. Thus, in this air diffuser 101, the air diffuser main body 102 can be rotated without requiring a special power source by providing the air diffuser holes 102a along the spiral line. In addition, the air can be partially concentrated on the membrane separator 5 and can be applied vigorously, and the clogging of the membrane separator 5 can be effectively prevented.

  A diffuser pipe 111 as a fifth example shown in FIGS. 21 to 23 includes a cylinder 112 into which air enters from the blower 15 via the air supply pipe 14, and a piston 113 arranged so as to be able to reciprocate in the cylinder 112. ing. A plurality of air diffusion holes 112a are provided on the upper surface side of the cylinder 112, and the piston 113 has a hollow cylindrical shape. One end of a shaft 114 is fixed to the piston 113. At this time, the shaft 114 is fixed to a support portion 113 a partially protruding inward from the inner surface of the cylindrical piston 113 so that air can flow inside the piston 113.

  The other end of the shaft 114 is connected to the pneumatic actuator 115. The pneumatic actuator 115 includes a cylinder 116 having ports 116a and 116b through which compressed air flows, a piston 117 disposed so as to reciprocate in the cylinder 116, a compressor 118 that generates compressed air, and compressed air from the compressor 118. An air supply pipe 119 having branch pipes 119a and 119b respectively led to ports 116a and 116b of the cylinder 116, and an air switch 120 including a three-way valve for switching the traveling direction of the compressed air to the port 116a or the port 116b.

  In the air diffuser 111, air flows from the blower 15 into the cylinder 112 through the air supply pipe 14, but the air that has flowed into the cylinder 112 spreads inside the cylinder 112 through the inside of the piston 113. At this time, the piston 113 closes about half of the plurality of air diffusion holes 112a, and air is ejected vigorously from the remaining air diffusion holes 112a. Therefore, when the position of the piston 113 is changed by the action of the pneumatic actuator 115, the piston 113 closes the other portions of the plurality of air diffusion holes 112a, and air vigorously ejects from the remaining air diffusion holes 112a. Therefore, this air diffuser 111 can also concentrate air on the membrane separator 5 and apply it vigorously, and can effectively prevent clogging of the membrane separator 5 due to sludge.

  Although the piston 113 has a hollow cylindrical shape, it can be a solid piston 121 as shown in FIGS. In this case, the cross-sectional shape of the piston 121 is formed by the arc portion 121a and the straight portion 121b. The arc portion 121a is larger than the semicircle, but a gap 122 is formed between the straight portion 121b and the cylinder 112. As a result, the air that has flowed into the cylinder 112 spreads throughout the piston 121, and even if this solid piston 121 is used, the same effect as the hollow piston 113 can be obtained.

  FIG. 24 shows another device for preventing clogging of the air diffuser 11. In this apparatus, a lower opening 131a of an air discharge pipe 131 is connected to a diffuser pipe 11 disposed below the membrane separator 5, and the upper opening 131b is positioned above the water surface of the raw water (treated water) 2. is there. An open / close valve 132 is provided in the air discharge pipe 131 outside the raw water (treated water) 2 so that air is discharged from the diffuser pipe 11 through the air discharge pipe 131 as necessary. Normally, the on-off valve 132 is closed, and the air from the blower 15 is diffused from the diffuser pipe 11 into the raw water (treated water) 2 of the membrane separation tank 3. Then, according to the state of the diffuser, for example, when the beginning of a state such as clogging in the diffuser tube 11 is felt, the on-off valve 132 is opened. As a result, air is ejected from the upper opening 131b through the air discharge pipe 131, so that the air flowing in the diffuser pipe 11 sucks the raw water (treated water) 2 into the diffuser pipe 11 as indicated by the arrow, and the diffuser pipe 11 is peeled off and allowed to flow out of the upper opening 131b to prevent the air diffuser 11 from being clogged.

  FIG. 25 shows that the diffusing tube 11 is installed at a place other than the lower side of the membrane separator 5. In the normal membrane separator 5, the upper and lower ends of the separation membrane 5a made of, for example, a hollow fiber membrane are fixed to the upper and lower support frames 141, 142, respectively, and the intervals between these support frames 141, 142 are, for example, the left and right support columns 143, 144. (The support column 144 is fixed later). Therefore, for example, the two diffuser tubes 11 can be arranged inside the support frame 142 at the lower part of the membrane separator 5 or between the bundles of the separation membranes 5 a of the membrane separator 5. When disposing the diffuser tube 11 between the bundles of the separation membranes 5a, it is preferable to dispose them as close to the lower end of the separation membranes 5a as possible. If the air diffuser 11 is installed in the lower support frame 142 or on the lower surface of the lower support frame 142, the air diffuser 11 can be kept horizontal, so that the air blown from the air diffuser 11 is separated from the separation membrane. It becomes possible to apply to 5a uniformly. In addition, when strongly diffusing directly on the separation membrane 5a, when intermittent operation is performed, or when the flow path is switched during backwashing, air may be sucked into the treated water pump 8 to cause water sealing. A gas-liquid separation tank can also be provided. Further, when the flow rate is reduced due to water sealing, two pumps can be operated simultaneously with a maximum capacity of 1.5Q to perform forced suction. Furthermore, gas / liquid separation can also be performed because water sufficient to fill the pump casing remains in the treated water piping. For example, it is good to set it as the structure which provides unevenness in a treated water piping and water accumulates in a treated water piping. For example, the gas-liquid separation tank may have a structure that detects the water level in the tank and sucks the air in the tank with a vacuum pump when the water level falls below a predetermined level.

  FIG. 26 shows a planar shape of the support frame 142 below the membrane separator 5. When a hollow fiber membrane is used for the separation membrane 5a of the membrane separator 5, the outer surface of the hollow fiber membrane can be easily washed by reducing the thickness of the bundle of hollow fiber membranes. In this case, the support frame 142 is provided with a plurality of air circulation ports 151 penetrating vertically, for example, in a zigzag manner, and the separation membrane 5a formed of a bundle of hollow fiber membranes is positioned between the air circulation ports 151. It is. Raw air (treated water) 2 and air can flow through the air circulation port 151, but a water flow nozzle or the like can also be installed. Alternatively, the efficiency of air diffusion can be improved by making the air diffuser 11 into a chimney shape and fitting it into the air circulation port 151. In addition, an air supply pipe 152 and a treated water suction pipe (treated water transfer pipe) 153 can be fixed to the support frame 142. Therefore, the upper support frame 141 can have the same configuration as the lower support frame 142. Thereby, the thickness of the bundle | flux of the separation membrane 5 can be made thin, the air which ejected from the air circulation port 151 can be flowed around the bundle | flux of the separation membrane 5a favorably, and sludge adheres between the bundle | flux of the separation membrane 5a. Can be prevented.

  The membrane separator 5 shown in FIG. 27 is configured such that even when sludge is adhered between bundles of separation membranes 5a made of hollow fiber membranes of the membrane separator 5, the sludge can be easily removed. . A separation membrane 5 a of a normal membrane separator 5 is supported by upper and lower support frames 141 and 142 and left and right support columns 143 and 144. However, here, one column 143 is divided into two upper and lower portions 143a and 143b to form a gap 145, and the other column 144 is also divided into two upper and lower portions 144a and 144b to form a gap 146. It is formed. And the external shape of the normal membrane separator 5 is hold | maintained by inserting the supporting members 147 and 148 in the clearance gaps 145 and 146, respectively. Thereby, when sludge adheres to the membrane separator 5, by removing the support members 147 and 148 from the support columns 143 and 144, respectively, the interval between the upper and lower support frames 141 and 142 is reduced, and the separation membrane 5a is The sludge between the hollow fiber membranes can be easily dropped. If the columns 143, 144 can be attached to and detached from the support frames 141, 142 without dividing the column vertically, the upper and lower support frames 141, 142 are bent while the separation membrane 5a is bent by removing the columns 143, 144. It is possible to reduce the interval between them, and the membrane separator 5 can be easily cleaned and transported.

  The membrane separator 5 shown in FIG. 28 has upper and lower ends of the separation membrane 5a supported by upper and lower auxiliary support frames 172 and 173 on a support frame 171 composed of upper and lower support frames 141 and 142 and left and right support columns 143 and 144. The separation membrane portion 174 formed is detachable in a cassette shape. Therefore, concave portions 141a and 142a into which the auxiliary support frames 172 and 173 are fitted are formed on the opposing surfaces of the support frames 141 and 142, respectively. In this case, it goes without saying that if the auxiliary support frames 172 and 173 and the recesses 141a and 142a are provided with a gradient, their fitting becomes easy. In the membrane separator 5, the separation membrane 5 a can be cleaned by removing the separation membrane portion 174 from the support frame 171. Further, since the height of the separation membrane part 174 is lower than the height of the support frame 171, the immersion cleaning tank of the separation membrane part 174 can be made smaller than the immersion cleaning tank of the normal membrane separator 5. Furthermore, only the separation membrane part 174 can be replaced and the support frame 171 can be used repeatedly. And since only the separation membrane part 174 has only to be pulled up from the membrane separation tank 3, the lifting height is also reduced, and the installation space is reduced. Moreover, since the size and weight of the separation membrane part 174 are made smaller and lighter than the size and weight of the membrane separator 5, transport during cleaning and replacement is facilitated.

  The membrane separator 5 shown in FIGS. 29 and 30 can be finely adjusted in the horizontal direction even after being installed in the membrane separation tank 3. That is, assuming that the membrane separation tank 3 is formed in a plane rectangle by the side wall 3a and the bottom wall 3b, and the accuracy of the finished dimension of the inner surface of the bottom wall 3b is poor, a platform on which the membrane separator 5 is placed is mounted. It becomes difficult to install horizontally. Therefore, when the membrane separator 5 is installed with the gantry tilted, it is difficult to evenly apply the air from the diffusion tube 11 to the separation membrane 5a. Therefore, in the membrane separator 5, the support frame 181 is fixed to the upper surface of the upper support frame 141, and the reference frame 182 is attached to the upper surface of the support frame 181 with a plurality of adjustment bolts 183. The support frame 181 is a planar rectangular frame along the edge of the support frame 141, and screw holes (not shown) for screwing bolts 183 are provided on a pair of opposite sides of the support frame 181. The interval between the opposing sides 182a and 182a of the reference frame 182 is equal to the interval between the opposing sides of the support frame 181, but the remaining opposing sides 182b and 182b of the reference frame 182 are the remaining opposing sides of the support frame 181. It is located outside.

  On the other hand, a pair of guide grooves 184 and 184 for guiding the opposing sides 182b and 182b of the reference frame 182 are formed on the upper inner surface of the side wall 3a of the membrane separation tank 3. The reference surfaces 184a and 184a at the base of these guide grooves 184 and 184 are provided so as to support the opposite sides 182b and 182b of the reference frame 182 and hold the membrane separator 5 at a predetermined height. Therefore, when the membrane separator 5 is installed in the membrane separation tank 3, all the adjustment bolts 183 are adjusted in advance so as to leave a slight parallel gap d between the support frame 181 and the reference frame 182. deep. Next, the opposing sides 182b and 182b of the reference frame 182 are fitted into the guide grooves 184 and 184 of the membrane separation tank 3, and the opposing sides 182b and 182b of the reference frame 182 are in the reference surfaces 184a and 184a of the guide grooves 184 and 184, respectively. The membrane separator 5 is lowered into the raw water (treated water) 2 until it comes into contact. Then, when adjusting the level of the membrane separator 5, the necessary adjustment bolt 183 is turned with the tool 185. Since the membrane separator 5 here can adjust the horizontal from the water surface after being immersed in the membrane separation tank 3, even if the finishing accuracy of the bottom face of the membrane separation tank 3 is poor, the state of air diffusion is monitored. However, the level of the membrane separator 5 can be adjusted. Thereby, the diffused air from the diffuser tube 11 can be uniformly applied to the separation membrane 5a, and the filtration efficiency of the separation membrane 5a can be kept high continuously. The reference frame 182 is fitted in the guide groove 184 of the side wall 3a of the membrane separation tank 3, but the support frame 181 is fixed to the upper surface of the support frame 141 at the upper part of the membrane separator 5, and the upper surface of the support frame 181 is fixed. It is also possible to attach the reference frame 182 to the support frame 181 and the reference frame 182 on a support stand in the membrane separation tank 3 and adjust the horizontal with the adjustment bolt 183. Is possible.

  The header 191 shown in FIG. 31 and FIG. 32 is configured so that a plurality of membrane separators 5 can be easily attached and any membrane separator 5 can be easily removed. Therefore, a water guide member 192 for guiding the treated water 4 to the header 191 is provided on the upper surface of the membrane separator 5 so as to protrude upward. The water guide member 192 is provided with a flow path 192a in a T shape. The header 191 is provided with a recess 194 that sequentially accommodates the valve body 193 and the water guide member 192 from below. The header 191 includes a first channel 195 that extends linearly in the horizontal direction and can communicate with the channel 192a of the water guide member 192, and a second channel that extends in parallel with the first channel 195 above the first channel 195. And a bypass 197 that communicates the first flow path 195 and the second flow path 196 on both sides of the recess 194. The valve body 193 closes the second flow path 196 when the membrane separator 5 is attached to the header 191, and automatically moves downward when the membrane separator 5 is removed from the header 191. The first flow path 195 is closed.

  Therefore, as shown in FIG. 31, when all the membrane separators 5 are attached to the header 191, all the valve bodies 193 are located above to close the second flow path 196, and the treated water 4 is indicated by an arrow. Thus, the first flow path 195 flows linearly. On the other hand, when, for example, the central membrane separator 5 is removed from the header 191, the valve body 193 at a position corresponding to the membrane separator 5 moves downward as shown in FIG. The second flow path 196 is opened and the first flow path 195 is closed. Thereby, as shown by the arrow, the treated water 4 heading toward the central concave portion 194 moves upward through one bypass 197 adjacent to the concave portion 194, flows horizontally through the second flow path 196, and the other bypass. Heading 197 downward, it joins the first flow path 195.

  Thus, conventionally, it was necessary to dismantle all the membrane separators 5 even when one of the plurality of membrane separators 5 was taken out for repair or cleaning. If 191 is used, an arbitrary membrane separator 5 can be easily removed in a short time without disassembling all the membrane separators 5. Moreover, since the remaining membrane separators 5 can be operated with the optional membrane separator 5 removed, the membrane filtration step can be continued without interruption, and the processing efficiency can be improved. Furthermore, since only the necessary membrane separator 5 can be easily removed, the time required for replacement, cleaning and maintenance of the membrane separator 5 can be shortened.

  The membrane separator 5A shown in FIG. 33 has the same structure for the upper and lower support frames 141 and 142, the separation membrane 5a made of a hollow fiber membrane is curved in a U shape, and the lower support frame 142 is placed on the upper support frame 141. The support frames 141 and 142 are connected to the treated water transfer pipe 7 at the same height. Thereby, since the height of 5 A of membrane separators becomes low, it can respond also when the water depth of the said membrane separation tank 3, the reaction tank 31, and the disinfection tank 51 is low. In this case, since the standard separation membrane 5a can be used, the correspondence is easy. Moreover, since the separation membrane 5a is U-shaped, the separation membrane 5a can be shaken by the air diffused from the air diffuser 11, and the physical cleaning effect can be improved.

  A membrane separator 5B shown in FIG. 34 has a separation membrane 5a made of a hollow fiber membrane in a loop shape, and both ends of the separation membrane 5a are fixed to an upper support frame 141, and weights 201 are attached to the inner surface of the lowermost portion of the separation membrane 5a. It is placed. The separation membrane 5a of the membrane separator 5B can be shaken in the same manner as the separation membrane 5a of the membrane separator 5A, but the magnitude of the shake of the separation membrane 5a can be adjusted by the weight of the weight 201. Therefore, by selecting the weight of the weight 201, the separation membrane 5a can be shaken appropriately, and the physical cleaning effect can be further improved.

  In the membrane separator 5C shown in FIG. 35, the upper end of the hollow fiber membrane constituting the separation membrane 5a is closed. The lower end of the separation membrane 5a is fixed in a cantilever manner to the lower support frame 142, and the upper end of the separation membrane 5a is a free end. The support frame 142 is connected to the treated water transfer pipe 7 while the left and right support columns 143 and 144 are left. In this membrane separator 5C, since the upper end of the separation membrane 5a can be shaken by aeration, the physical cleaning effect can be improved. Note that the left and right support columns 143 and 144 may be omitted.

  FIG. 36 shows a case where the membrane separator 5 is installed at an angle θ with respect to the vertical direction. In this case, after the bubble rising in the vertical direction from the air diffuser 11 hits the separation membrane 5a, it rises along the lower surface of the separation membrane 5a, and the sludge adhering to the separation membrane 5a is efficiently separated as a whole. . Further, if the membrane separator 5 is tilted, the membrane separation tank 3, the reaction tank 31, and the disinfection tank 51 having a shallow water depth can be handled. Therefore, it is not necessary to prepare a membrane separator with a low height as in the prior art, and the equipment cost can be reduced.

  A carrier (cube shape, sphere shape, capsule shape, etc.) can be put into the membrane separation tank 3 to flow the raw water (water to be treated) 2 to retain microorganisms, thereby improving the biological treatment capacity. In this case, the carrier flows in the membrane separation tank 3 and collides with the separation membrane 5a, thereby peeling off the membrane surface deposit attached to the separation membrane 5a from the separation membrane 5a. Therefore, the carrier needs to have a hardness that does not damage the separation membrane 5a when it collides with the separation membrane 5a. A polyurethane sponge can be used as this type of carrier, but is not particularly limited. The separation membrane 5a is washed by aeration, but a water flow is generated in the membrane separation tank 3 due to the aeration, and this water flow causes the carrier to flow and collide with the separation membrane 5a. The kimono is peeled off from the separation membrane 7. The carrier has a great effect of improving biological treatment capacity and physically removing deposits on the film surface.

  For example, a flat membrane is used for the separation membrane 5a, the carrier is a cubic porous polyurethane having a side of 12 mm, and the carrier is separated from the membrane separation tank so that the ratio between the volume of the carrier and the volume of the membrane separation tank 3 is 10%. 3 is set as one condition, the other conditions are the same, and the case where the carrier is charged is compared with the case where the carrier is not charged, the increase in the transmembrane pressure difference can be suppressed by about 30%. Further, the membrane surface adhering matter adhering to the separation membrane 5a can be lowered by about 70% when the carrier is introduced compared to when the carrier is not introduced. Furthermore, even if the suspended sludge concentration is low, by increasing the amount of carrier added, it is possible to obtain a treated water quality that is equal to or better than when the suspended sludge concentration is high, and a larger sedimentation tank. Even if not, the processing amount can be increased. The carrier is also effective for sludge retention as a countermeasure for low load. Moreover, the load on the separation membrane 5a is reduced by the microorganisms adhering to the carrier. Furthermore, since the SRT of the attached sludge on the carrier becomes longer, there is an effect of removing environmental hormones and chromaticity.

  Further, when the apparatus of the present invention is used for water treatment, when the carrier is flowed, the physical cleaning effect due to the collision of the carrier, and further, the purification effect when activated carbon is added, for example, dissolution In addition to the effect of removing the active substance, it can be expected to reduce the load on the separation membrane 5a due to the living organisms attached to the carrier. The activated carbon may be granular activated carbon or powder activated carbon as long as it does not affect the abrasion of the separation membrane 5a. Moreover, the low load countermeasure effect with respect to the separation membrane 5a can also be obtained by holding the sludge on the carrier. Moreover, the environmental hormone removal effect by SRT becoming long can also be expected. Note that the physical cleaning effect due to the collision is particularly remarkable in a flat film.

It is a flowchart of the water treatment apparatus which shows Embodiment 1 of this invention. It is a schematic diagram of a rotary valve. It is a layout when an air switch is constituted by an electric cylinder valve. It is a flowchart of the water treatment apparatus which shows Embodiment 2 of this invention. It is a schematic diagram of a rotary valve. It is a layout when an air switch is constituted by an electric cylinder valve. It is a flowchart of the water treatment apparatus which shows Embodiment 3 of this invention. It is a flowchart of the water treatment apparatus which shows Embodiment 4 of this invention. It is a perspective view of an ultraviolet shielding plate, (a) shows a semi-cylindrical ultraviolet shielding plate, and (b) shows a semi-cubic ultraviolet shielding plate. It is a principal part block diagram of the water treatment apparatus which shows Embodiment 5 of this invention, (a) is a longitudinal cross-sectional view, (b) is a top view. It is a principal part block diagram of the water treatment apparatus which shows Embodiment 6 of this invention. It is the action explanatory view. The 1st example of a diffuser tube is shown, (a) is a top view, (b) is a bottom view with the cap removed, and (c) is a side view with the cap removed. It is a longitudinal cross-sectional view of the 2nd example of a diffuser tube. FIG. It is the action explanatory view. It is a longitudinal cross-sectional view of the 3rd example of a diffuser tube. It is a perspective view of a diffuser main body. It is the action explanatory view. It is a partial longitudinal cross-sectional view of the 4th example of an air diffuser. It is a fragmentary longitudinal cross-section of the 5th example of an air diffuser. It is a fragmentary longitudinal cross-section which shows the other form of a piston. FIG. It is a fragmentary longitudinal cross-section which shows the state which connected the air exhaust pipe to the diffuser pipe. It is a schematic diagram which shows the arrangement position of a diffuser tube. It is a top view of a lower support frame. It is a front view of the membrane separator which removes and shows a support member. It is a block diagram which shows the state which removed the separation membrane part from the support | pillar frame of a membrane separator. It is a top view explaining the apparatus which prepares the horizontal of a membrane separator. It is the fragmentary longitudinal cross-sectional view. It is a partial longitudinal cross-sectional view of the header which makes a some membrane separator detachable. It is the action explanatory view. It is a figure explaining installing a separation membrane in U shape. It is a figure explaining installing a separation membrane in a loop shape. It is a figure explaining making the upper end of a separation membrane into a free end. It is a figure explaining installing a membrane separator inclining.

Explanation of symbols

1 Raw water introduction means 2 Raw water (treated water)
3 Membrane separation tank 4 Treated water 5, 5A, 5B, 5C Membrane separator 5a Separation membrane 6 Treated water tank 7, 153 Treated water transfer pipe (treated water suction pipe)
11, 71, 81, 91, 101, 111 Air diffuser 13 Air switch 16 Air supply equipment 31 Reaction tank 21, 27 Rotary valve 41 Photocatalyst 42 Ultraviolet irradiator 43, 43A, 43B Ultraviolet shielding plate 72 Air diffuser hole 75 Opening port 106 Screw blade 113, 121 Piston

Claims (6)

  Raw water introduction means, a membrane separation tank provided with a plurality of membrane separators and a plurality of diffuser tubes, an air supply facility for supplying air to the diffuser tubes, and a treated water transfer for transferring treated water connected to the membrane separator The water treatment apparatus which consists of a pipe | tube WHEREIN: The said air supply equipment is provided with an air switch, The water treatment apparatus characterized by the above-mentioned.   The water treatment apparatus according to claim 1, wherein the air switch is a rotary valve.   The water treatment apparatus according to claim 1, wherein the air diffuser has a reciprocating piston.   The water treatment apparatus according to claim 1, wherein the air diffuser has screw blades that rotate.   The water treatment apparatus according to claim 1, wherein the air diffuser has air diffuser holes on an upper surface and an open port on a lower surface.   6. The water treatment apparatus according to claim 1, wherein the membrane separation tank includes an ultraviolet irradiator and an ultraviolet shielding plate, and the photocatalyst flows.

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