JP2009106874A - Reaction tank and aeration device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reaction tank and an aeration device which can uniformize an effect of removing extraneous matter from an aeration hole, eliminate necessity of controlling the purchase cost of a chemical liquid, and wash the aeration hole by exerting no bad influence on treated water quality. <P>SOLUTION: The reaction tank 24 comprises a plurality of flat membranes 28 immersed in the reaction tank 24, piping 30 for taking out treated water filtered with the flat membranes 28, an aeration pipe 10 installed below the flat membranes 28 and having a plurality of aeration holes 12, an injection device sending air for aeration into the aeration pipe 10, and an aeration device provided in the aeration pipe 10 and having a part for peeling off the deposited matter adhering to the aeration holes 12. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a reaction tank and a diffuser using an immersion type membrane module.

  As a sewage treatment apparatus using an immersion type membrane module, for example, there is one in which a plurality of external pressure solid-liquid separation flat membranes are arranged in a reaction tank so that their membrane surfaces are vertical. In such a sewage treatment apparatus, air bubbles are aerated from an air diffuser installed in the lower part of the reaction tank. The purpose of this aeration of air bubbles is to supply oxygen to the microorganisms that make up the activated sludge in the reaction tank, wash the membrane surface with the water flow generated as the bubbles rise, and remove deposits on the membrane surface. It is to prevent clogging.

  In such a sewage treatment apparatus, it is possible to prevent the turbid components from flowing out, so that the activated sludge can be operated at a higher concentration than in the case of solid-liquid separation in the final sedimentation basin. As a result, the apparatus can be miniaturized and the generated sludge can be reduced.

  In the membrane-separated activated sludge method, the diameter of the air diffuser in the air diffuser is 3-10 mm, because the activated sludge concentration is high and the membrane surface cleaning effect cannot be obtained unless the air bubbles are larger than a certain size. In general, a diffuser having a structure in which a plurality of holes of this size are formed in a pipe is used.

  The air diffuser is designed and manufactured so that air bubbles are uniformly injected into the reaction tank from each air diffuser so that the cleaning effect on the membrane surface does not vary. However, during continuous operation, solid matter gradually adheres to the air holes. This is thought to be one of the reasons that the activated sludge dries because the temperature of the pressurized air is high.

  In the air diffuser to which the solid matter adheres, the flow rate of the air passing therethrough decreases, so that the parallel flow speed of the activated sludge liquid on the outside of the air diffuser decreases, and the adherence of the adhering matter is further accelerated. As a result, a difference occurs in the amount of adhering matter for each air hole, resulting in a difference in the amount of air diffused and uneven cleaning of the film surface. In order to remove the deposits on the air diffuser, for example, conventional techniques and methods described in [Patent Document 1] to [Patent Document 4] have been proposed.

  [Patent Document 1] temporarily increases the flow rate of air supplied to the air diffuser when the air diffuser is clogged, and removes deposits by the fluid resistance of the air. In [Patent Document 2], when the diffuser tube is clogged, water is injected from the outside into the diffuser tube, and water is pushed out from the diffuser hole by the pressure of the supply air, and the deposit is removed by the fluid resistance of the water. Is. In [Patent Document 3], the activated sludge outside the diffuser pipe is caused to flow back into the diffuser pipe, the adhering matter is moistened, and then extruded from the diffuser holes together with the activated sludge by the pressure of the supplied air. The deposit is removed by fluid resistance.

  However, the deposit removal technique and method described in [Patent Document 1] to [Patent Document 3] have the following problems, and a sufficient removal effect cannot be obtained. The method of injecting liquid or gas into the diffuser tube and removing the deposits using the fluid resistance has a problem that the removal effect differs depending on the flow velocity of the fluid passing through the diffuser holes.

  When fluid is applied to the air diffuser at the same pressure, the flow velocity of the fluid at the diffuser hole with the smallest amount of deposit is the largest, and conversely, the fluid flow velocity at the diffuser hole with the largest amount of deposit and clogging is the same. Smallest. That is, the cleaning effect of the diffuser with the most adhering matter is the smallest. As a result, it is necessary to flow a large amount of fluid for a long time in order to solve the non-uniformity of aeration, and the operation stop time of the membrane separation activated sludge treatment apparatus becomes longer. Even when a large amount of fluid is flowed for a long period of time, the phenomenon that the flow velocity of the fluid in the air diffuser with the least amount of deposits remains the same is not changed, and in some cases, the unevenness of the air diffused amount may be further deteriorated.

  Therefore, in the conventional technique described in [Patent Document 4], a cleaning chemical solution is injected into the aeration tube, and deposits are removed using a chemical reaction of the chemical solution.

JP 2003-181480 A JP 2005-152777 A JP 2002-166290 A JP 2003-154236 A

  In the method described in [Patent Document 4], it is possible to expect an equal cleaning effect for all the air holes regardless of the amount of deposits. However, the method using the chemical for cleaning has a negative effect on the activity of microorganisms and the quality of treated water as well as the cost of purchasing the chemical and management work. It is possible to reversely collect the chemical after washing from the air diffuser so that the quality of the treated water is not adversely affected. However, in that case, there is a problem that costs and labor related to waste liquid treatment of the recovered chemical are newly generated. .

  Further, while the non-uniformity of the amount of air diffused in each air diffuser of the air diffuser is a problem, no technical proposal for measuring and evaluating the degree of non-uniformity from the outside has been found so far.

  An object of the present invention is to provide a reaction tank and a diffuser that can uniformize the effect of removing deposits with diffused holes, do not require the purchase cost or management of chemicals, and can perform diffused hole washing without adversely affecting the quality of treated water There is to do.

  In order to achieve the above-mentioned object, the present invention includes an air diffuser tube that is arranged so as to be immersed in a reaction vessel and has a plurality of air diffusers, an injection device that sends air to diffuse air into the air diffuser, and an air diffuser. And an exfoliation / removal part for the adhering matter of the air diffuser provided in the tube.

  Also, a plurality of flat membranes immersed in the reaction vessel, a pipe for taking out treated water membrane-filtered by the flat membrane, a diffuser tube installed below the plurality of flat membranes and having a plurality of air diffusion holes, And an infusion device for sending air for diffusing into the diffusing tube, and an diffusing device provided in the diffusing tube and having an exfoliation / removal part for the adhering matter of the diffusing holes.

  According to the present invention, it is possible to effectively remove the adhering matter of the air diffuser of the air diffuser, so that a uniform air diffused state can be maintained. In the case of the membrane separation activated sludge method, the effect of removing the adhering matter on the membrane surface The water treatment performance can be improved.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram of an air diffuser including a nozzle according to a first embodiment of the present invention. As shown in FIG. 2, for example, the air diffuser is immersed in the bottom of the reaction tank 24 of the membrane separation activated sludge treatment apparatus. The water to be treated 26 to be treated is contained in the reaction tank 24, and the air for diffusion 22 flowing in from the air diffuser connection port 14 of the air diffuser 10 enters the water to be treated 26 from the plurality of air diffusers 12. Injected as bubbles. For example, a blower or a compressor (not shown) is used as an apparatus for injecting the air 22 for air diffusion, and the air 22 for air diffusion is sent into the air diffusion pipe 10 by the communication pipe 48 in the air diffusion pipe.

  A plurality of flat membranes 28 are installed in the reaction tank 24 in the vertical direction. Bubbles aerated between the flat membranes 28 rise to clean the membrane surface and remove the deposits. Suppresses clogging.

  The treated water 26 that has flowed into the reaction tank 24 is filtered by the flat membrane 28 and taken out from the pipe 30 as treated water. The water to be treated 26 is, for example, a liquid containing high-concentration activated sludge, but may be an activated sludge liquid having a low concentration.

  For example, as shown in FIG. 1, the air diffuser 10 has a cylindrical shape, and both ends are sealed with plates. A cleaning fluid pipe 18 is provided above the diffuser tube 10, and a space is formed in the diffuser tube 10. The air diffuser 10 is provided with a nozzle 16 toward the air diffuser 12. The nozzle 16 communicates with a cleaning fluid pipe 18, and the cleaning fluid pipe 18 is connected to a cleaning fluid injection device (not shown) by a pipe (not shown). By operating the cleaning fluid injection device, the cleaning fluid 20 is ejected from the cleaning fluid pipe 18 toward the diffuser holes 12. The cleaning fluid injection device is constituted by a pump or a blower. Here, as shown in FIG. 1, it is desirable that the position of the nozzle 16 outlet is located above the diffuser pipe connection port 14 in the vertical direction.

  In the example shown in FIG. 1, the air diffuser 12 is disposed below the vertical direction and the nozzle 16 is disposed above the vertical direction. However, the disposition of the air diffuser 12 and the nozzle 16 is not limited to this, and for example, the air diffuser. When the nozzle 12 is not located below the vertical direction, a plurality of nozzles 16 may exist for one air diffuser 12, and the cleaning fluid 20 may be ejected toward the air diffuser 12.

  The cleaning fluid 20 is preferably a liquid, but may be a gas or a mixture of liquid and gas. In order to further enhance the cleaning effect, hot water or steam having a high temperature may be used as the cleaning fluid 20.

  The operation of the air diffuser configured in this way will be described. The diffuser removes the deposits by the kinetic energy of the fluid ejected from the nozzle 16 which is a part for removing and removing the deposits. Although a method of causing a fluid to collide from the outside of the air diffuser can be considered, since the viscosity of the activated sludge liquid is high, most of the kinetic energy of the cleaning fluid is dissipated before reaching the deposit, and effective cleaning is difficult. Further, since the nozzle outlet contacts the activated sludge liquid, the nozzle outlet tends to be clogged.

  On the other hand, in the present embodiment, as described above, the nozzle 16 is provided in the diffuser tube 10, so that the cleaning fluid 20 ejected from the nozzle 16 has sufficient kinetic energy. Therefore, it passes through the air 22 for diffusion and reaches the diffusion hole 12. The cleaning fluid 20 passes through the diffuser holes 12 and then enters the treated water 26 to lose kinetic energy.

  Therefore, the kinetic energy of the cleaning fluid 20 can be used for the separation and removal of the deposits with little loss with respect to the deposits generated near the air diffusion holes 12. Further, since the air diffuser 10 is filled with the air diffuser 10, the nozzle 16 is hardly clogged with solid matter such as activated sludge contained in the water to be treated 26.

  As a result, since the cleaning fluid 20 having the same kinetic energy can be ejected from any of the diffuser holes 12, a uniform cleaning effect can be obtained regardless of the amount of deposits on the diffuser holes 12, and the amount of diffused air can be made uniform. Realized.

  In the long term, the nozzle 16 may be clogged, but each time it can be easily dealt with by injecting cleaning chemicals, hot water, high-temperature steam, etc. into the cleaning fluid pipe 18 under pressure. It is. The cleaning frequency of the nozzle 16 is extremely low, and the amount of the chemical solution required is very small because the volume of the cleaning fluid pipe 18 and the nozzle 16 is sufficient.

  The kinetic energy of the cleaning fluid 20 ejected from the nozzle 16 toward the deposit on the air diffuser 12 is proportional to its mass and proportional to the square of the ejection speed. Therefore, if the mass is equal, the higher the ejection speed, the greater the effect, and if the ejection speed is equal, the larger the mass is desirable.

  In order to obtain a greater cleaning effect, it is preferable to use hot water as the cleaning fluid 20. Since hot water has a smaller viscous resistance than cold water, it is ejected from the nozzle 16 at a higher speed. Further, when the deposit is dry, the time required for the warm water to be wetted is shorter than the cold water, and the deposit can be removed in a shorter time.

  As described above, it is desirable that the cleaning fluid 20 is a liquid, particularly a liquid having a high temperature. However, even if it is a gas, there is no problem as long as the ejection speed is sufficiently high. The cleaning fluid 20 may be a mixture of liquid and gas, and the cleaning fluid 20 may include a solid that contributes to cleaning.

  Practically, it is desirable that the position of the jet outlet of the nozzle 16 be positioned above the diffuser pipe connection port 14 in the vertical direction, thereby reducing the possibility of clogging of the jet outlet. Normally, the water to be treated 26 does not flow into the air diffuser 10 during the period when the air 22 for air diffusion is injected to generate bubbles. However, if a malfunction occurs in a device that injects the air 22 for aeration, such as a blower, a valve, or a pipe, the treated water 26 may flow into the air diffuser 10. In this case, for example, as shown in FIG. 1, if the position of the nozzle 16 outlet is vertically above the diffuser tube connection port 14, the nozzle 16 jets even if the water to be treated 26 flows into the diffuser tube 10. Since an air pool is generated in the space including the outlet, the jet outlet of the nozzle 16 does not come into contact with the water to be treated 26. As a result, it is possible to maintain the function of ejecting the cleaning fluid 20 having the same kinetic energy from the nozzle 16 to any of the diffuser holes 12 for a longer period of time.

  FIG. 3 is a schematic diagram of an air diffuser including a sliding body according to a second embodiment of the present invention. As shown in FIG. 2, the air diffuser of the present embodiment is also installed by being immersed in the bottom of the reaction tank 24 of the membrane separation activated sludge treatment apparatus, for example. The water to be treated 26 to be treated is contained in the reaction tank 24, and the air for diffusion 22 flowing from the air diffuser connection port 14 of the air diffuser 10 is bubbled into the water to be treated 26 from the plurality of air diffusers 12. As injected. The treated water 26 is assumed to be a liquid containing, for example, a high concentration activated sludge, but an activated sludge liquid having a low concentration may be used.

  Inside the air diffuser 10, there are provided a sliding body driving device 36 which is a part for removing and removing the adhered matter, and a sliding body 34 driven by the sliding body driving device 36. At the time of cleaning to remove the deposit, the sliding body 34 moves through the air diffuser 12. During normal operation, the sliding body 34 moves to a position that does not obstruct the flow of the air 22 for aeration flowing through the air holes 12. The sliding body 34 may have any shape as long as it is solid, but considering the entanglement of the fibrous substance contained in the activated sludge liquid, a cylindrical shape or a tapered cylindrical shape is preferable instead of a brush.

  The sliding body drive device 36 may be any mechanism that can move the sliding body 34 in parallel toward the air diffuser 12 and may be any one of electromagnetic drive, motor drive, hydraulic drive, pneumatic drive, and wire drive. In particular, in the case of electromagnetic drive or motor drive, it is relatively easy to operate each slide body 34 individually. The kimono can be effectively removed. In addition, it is possible to externally monitor the state of deposits and the like from the relationship between the voltage / current waveform and the operation time. Moreover, it is desirable that the installation position of the sliding body drive device 36 is located above the vertical direction as compared with the air diffuser connection port 14.

  The operation and action of the air diffuser configured as described above will be described.

  The deposit is mechanically removed by the kinetic energy of the sliding body 34. Since the sliding body 34 and the sliding body driving device 36 are provided in the air diffuser 10, the sliding body 34 and the sliding body driving device 36 are clogged or defective due to solid matter such as activated sludge contained in the water to be treated 26. It hardly occurs. As a result, the same kinetic energy can be applied to any of the diffuser holes 12 to remove the deposits, so that a uniform cleaning effect can be obtained regardless of the amount of deposits on the diffuser holes 12. As a result, the amount of diffused air is made uniform.

  Practically, it is desirable that the position of the sliding body driving device 36 is located above the diffuser pipe connection port 14 in the vertical direction. This can reduce the possibility that the sliding body driving device 36 has a problem. Normally, the water to be treated 26 does not flow into the air diffuser 10 during the period when the air 22 for air diffusion is injected to generate bubbles. However, if a malfunction occurs in a device for injecting air 22 such as a blower, a valve, or piping, the treated water 26 may flow into the air diffuser 10. In that case, if the position of the sliding body drive device 36 is above the diffuser pipe connection port 14 in the vertical direction, even if the water 26 to be treated flows into the diffuser pipe 10, an air pocket is left in the space including the slide body drive apparatus 36. Therefore, the sliding body driving device 36 does not come into contact with the water to be treated 26. As a result, the function that the sliding body 34 removes the deposit with the same kinetic energy can be maintained for a longer period of time.

  If there is no functional problem even when the sliding body driving device 36 contacts the water to be treated 26, it is not necessary to provide the sliding body driving device 36 inside the diffuser tube 10. You may be prepared for.

  FIG. 4 is a schematic diagram of an air diffuser including a valve mechanism according to a third embodiment of the present invention. As shown in FIG. 2, the air diffuser of the present embodiment is also installed by being immersed in the bottom of the reaction tank 24 of the membrane separation activated sludge treatment apparatus, for example. The water to be treated 26 to be treated is contained in the reaction tank 24, and the air for diffusion 22 flowing from the air diffuser connection port 14 of the air diffuser 10 is bubbled into the water to be treated 26 from the plurality of air diffusers 12. As injected. The treated water 26 is assumed to be a liquid containing, for example, a high concentration activated sludge, but an activated sludge liquid having a low concentration may be used.

  Inside the air diffuser 10, there are provided a valve mechanism driving device 40 that is a part for removing and removing the deposit, and a valve mechanism 38 driven by the valve mechanism driving device 40. The valve mechanism driving device 40 moves the valve mechanism 38 to close a part of the plurality of air diffusion holes 12 or reduce the effective area of the part of the air diffusion holes 12. As the valve mechanism driving device 40, any one of electromagnetic driving, motor driving, hydraulic driving, pneumatic driving, and wire driving is applied. In particular, electromagnetic driving or motor driving is desirable because it is relatively easy to operate each valve mechanism 38 individually. In addition, it is possible to monitor the operating status of the valve mechanism 38 based on the relationship between the voltage / current waveform and the operating time when operating power is supplied. As for the installation position of the valve mechanism drive device 40, it is desirable to be located above the aeration pipe connection port 14 in the vertical direction.

  In the present embodiment, since it is configured as described above, it is possible to individually close some of the air holes 12 or reduce the effective area of some of the air holes 12. As a result, the air for aeration 22 can be diffused intensively into the water to be treated 26 from the remaining air diffusion holes 12 in the open state.

  The operating state of the valve mechanism 38 is monitored externally based on the relationship between the voltage / current waveform and the operating time when operating power is supplied, so that the air diffuser 12 with a large amount of adhering matter is discriminated and the air diffuser 12 is opened. By carefully selecting the diffuser holes 12 having a large amount, the deposits can be removed, and the amount of diffused air from each diffuser hole 12 can be made uniform. Moreover, you may make it change the diffuser hole 12 made into an open state periodically in order.

  When water or cleaning liquid is introduced into the diffuser pipe 10 from the diffuser pipe connection port 14 for cleaning instead of the diffused air 22, or the treated water 26 is once flown back into the diffuser pipe 10 and diffused. In the case where the air 22 is blown and the deposits are removed using the fluid resistance of the liquid, the diffuser holes 12 having a large amount of deposits are selected as the diffuser holes 12 to be opened in the same manner. The amount of air diffused from the air diffuser holes 12 can be made uniform.

  In practice, it is desirable that the position of the valve mechanism driving device 40 is located above the diffuser pipe connection port 14 in the vertical direction, thereby reducing the possibility of occurrence of problems in the valve mechanism driving device 40.

  Normally, the water to be treated 26 does not flow into the air diffuser 10 during the period when the air 22 for air diffusion is injected to generate bubbles. However, if a malfunction occurs in a device that injects the air 22 for aeration, such as a blower, a valve, or a pipe, the treated water 26 may flow into the air diffuser 10.

  In addition, when water or a cleaning liquid is introduced into the diffuser pipe 10 from the diffuser pipe connection port 14 for cleaning instead of the diffused air 22, or after the water 26 to be treated has flowed back into the diffuser pipe 10 once. When the diffused air 22 is blown and the deposits are removed using the fluid resistance of the liquid, the liquid is present in the diffuser tube 10.

  In that case, if the position of the valve mechanism driving device 40 is above the diffuser pipe connection port 14 in the vertical direction, the space including the valve mechanism drive device 40 even if liquid such as the water to be treated 26 flows into the diffuser pipe 10. Therefore, the valve mechanism driving device 40 does not come into contact with liquid such as the water to be treated 26. As a result, the function of the valve mechanism 38 can be maintained for a longer period.

  If no functional problem occurs even when the valve mechanism driving device 40 comes into contact with the water to be treated 26, the valve mechanism driving device 40 does not need to be provided inside the diffuser tube 10, and the outside of the diffuser tube 10 is not necessary. You may be prepared for.

  FIG. 5 is a schematic diagram of an air diffuser equipped with a cleaning fluid heating apparatus that is Embodiment 4 of the present invention. A cleaning fluid injection device 44 is provided in the communication pipe 48 in the diffusion tube connected to the diffusion tube 10, and the cleaning fluid injection device 44 is connected to the cleaning fluid heating device 42.

  The cleaning fluid 46 is heated by the cleaning fluid heating device 42 and supplied to the cleaning fluid injection device 44 as warm water or water vapor. The cleaning fluid injection device 44 is connected to the inside of the diffuser pipe 10 through a communication pipe 48, and sends the cleaning fluid 46 to the inside of the diffuser pipe 10.

  The operation and action of the air diffuser configured as described above will be described.

  The cleaning fluid 46, which is warm water or water vapor, reaches the deposits uniformly attached to the air diffusion holes 12, so that the deposits can be wetted quickly and the cleaning effect is enhanced. The cleaning fluid 46 that has entered the treated water 26 beyond the area where the deposits are present loses heat and becomes harmless low-temperature water. Therefore, unlike the case of using a chemical solution such as a chemical, there is no problem of a decrease in microbial activity, the influence of the chemical solution remaining in the treated water quality, or a problem of reaction by-products. For this reason, a waste liquid processing apparatus and waste liquid processing work, a waste liquid recovery apparatus and waste liquid recovery work, etc. are unnecessary.

  Warm water or water vapor can be generated simply by heating water, and both the initial cost and running cost are extremely small compared to the case of using a chemical solution.

  FIG. 6 is a schematic diagram of an air diffuser including a bubble generation sensor according to Embodiment 5 of the present invention.

  The bubble generation sensor 50 is disposed on the outer surface of the diffuser tube 10. When the aeration air 22 is not supplied, the bubble generation sensor 50 is immersed in the water to be treated 26. When the aeration air 22 is supplied, at least a part of the bubble generation sensor 50 is present. Bubbles are generated. The bubble generation sensor 50 converts temporal changes such as pressure fluctuations, electric resistance fluctuations, electric capacity fluctuations, temperature fluctuations, and the like caused by the generation of bubbles into electrical signals. For the bubble generation sensor 50, for example, a pressure sensing device such as a strain gauge or conductive rubber, an exposed electrode disposed oppositely, a non-exposed electrode disposed oppositely, or a temperature sensing device such as a thermistor is used.

  The output signal of the bubble generation sensor 50 is transmitted via a wireless or wired communication line, and measured values are collected. It is desirable to collect the measured values at all times. However, if it is not urgent, a connector terminal connected in a signal manner to the bubble generation sensor 50 is provided outside the reaction tank 24, and a time interval such as during maintenance is provided. The information may be collected by connecting an information device to the connector terminal as appropriate.

  The bubble generation sensor 50 only needs to be able to capture temporal changes caused by the generation of bubbles, and may be disposed anywhere on the outer surface of the diffuser tube 10, but may be disposed so that a part thereof is in contact with the diffuser holes 12. desirable. By disposing the bubble generation sensor 50 in this manner, for example, by the method for cleaning the air diffusion holes 12 described in the first to fourth embodiments, the deposits attached to the sensor surface can be removed at the same time. When it cannot arrange | position so that the diffuser hole 12 may be contacted, you may arrange | position in the location where a bubble passes with high frequency on the outer surface of the lower half of the diffuser tube 10.

  The operation and action of the air diffuser configured as described above will be described.

  The diffuser tube 10 having a plurality of diffuser holes 12 is immersed in the bottom of the reaction vessel 24 as shown in FIG. Since generally opaque water 26 such as activated sludge liquid is contained in the reaction tank 24, it cannot be measured at all from the outside how much deposits are attached to the air diffusion holes 12.

  In the present embodiment, since it is configured as described above, it is possible to measure from the outside how much deposits are attached to the diffuser holes 12. Based on this measured value, it can be determined which diffuser holes 12 should be cleaned intensively, and a uniform diffuser amount can be realized more efficiently.

  An example of a signal when a pressure sensing device is used as the bubble generation sensor 50 is shown in FIG. The diameter of the bubble generated from the air diffuser 12 to which a large amount of deposits are attached is small and the frequency of occurrence is low. On the other hand, the diameter of the bubbles generated from the diffuser holes 12 with few deposits is large and the frequency of occurrence is high.

  These determinations can be made from the obtained signals. Specifically, the generation frequency of bubbles is known from the period T shown in FIG. The time t1 indicates the passage time of the bubble, and the bubble diameter can be estimated from this value. Further, since the change amount Δp is generated by the buoyancy of the bubbles, the bubble diameter can be estimated from the average value, the maximum value, and the minimum value. As a result, it is determined that the air diffuser 12 with the longest period T and the smallest average value of the time t1 and the amount of change Δp has the most adhering matter, and the air diffuser 12 is intensively washed to concentrate the air diffused amount. Can be made more uniform.

  FIG. 8 is a schematic diagram of a membrane separation activated sludge treatment apparatus equipped with a monitoring device 52 for an air diffuser that takes in the bubble generation information 54 obtained by the bubble generation sensor 50 and presents the information to the operator.

  The air diffuser monitoring device 52 displays a table or graph with the number of the air diffuser on one axis and the number of the air diffuser on the other axis on the screen of the display device. In the table or graph, at least the physical quantities related to the bubbles generated from each air hole are displayed using numerical values, colors, and shades. By this display, the operator can easily determine which diffuser hole 12 of which diffuser tube 10 has the most amount of deposits, and can perform cleaning more efficiently.

  Desirably, the air diffuser monitoring device 52 includes an automatic cleaning control device having a cleaning execution timing determination unit that determines the cleaning execution timing based on the bubble generation information 54 obtained by the bubble generation sensor 50. . The timing of performing cleaning is determined, for example, when the amount of deposits exceeds a set value or when the deviation from the average value of the estimated deposits of all the diffuser holes 12 exceeds a set value. Is done. The automatic cleaning control device generates, for example, a signal for operating the cleaning mechanism described in the first embodiment, and when the nozzle 16 shown in the first embodiment is used based on the signal, for example, a pump for feeding the cleaning fluid 20 Is activated. When the sliding body 34 shown in the second embodiment is used, electric power is sent to the sliding body driving device 36, or a pump and a blower for sending a driving fluid are started. When the valve mechanism 38 described in the third embodiment is used, electric power is sent to the valve mechanism driving device 40, or a pump and a blower for sending a driving fluid are started. When the cleaning fluid 46 described in the fourth embodiment is used, electric power is sent to the cleaning fluid heating device 42 and the cleaning fluid injection device 44. The automatic cleaning control device may send a signal to the cleaning timing to the existing cleaning mechanism.

  FIG. 9 is a schematic diagram of an air diffuser provided with a humidifier according to Embodiment 6 of the present invention. A humidifier 56 is provided in the diffuser pipe communication pipe 48 connected to the diffuser pipe 10, and the humidifier 56 injects water vapor or mist-like water particles into the diffuser pipe 10.

  Since it comprises in this way, the humidity of the air 22 for aeration becomes high, it can prevent that the activated sludge near the aeration hole 12 dries, and can suppress generation | occurrence | production of a deposit | attachment.

  This eliminates the need for a special air hole cleaning mechanism, a cleaning chemical, and a cleaning process. The humidifier 56 only needs to heat or spray water, and the initial cost and running cost are extremely low. When the humidifying device 56 is provided with a mechanism for ejecting mist-like water particles, the water particles take heat when they evaporate in the aeration air 22, and therefore the temperature of the aeration air 22. As a result, it becomes possible to further prevent the activated sludge near the air diffuser 12 from drying.

  FIG. 10 is a schematic diagram of an air diffuser provided with a cooling mechanism according to a seventh embodiment of the present invention. A cooling mechanism 58 is provided in the diffuser pipe communication pipe 48 connected to the diffuser pipe 10. The cooling mechanism 58 only needs to have a function of lowering the temperature of the air 22 for diffusion, and includes a heat exchanger. The cooling principle may be air cooling, water cooling, mechanical cooling or electrical cooling. Further, as described in the sixth embodiment, a method of lowering the temperature of the air 22 for aeration by the heat of vaporization of sprayed mist-like water may be used.

  Since it is comprised in this way, the temperature of the air 22 for aeration becomes low. As a result, it is possible to prevent the activated sludge in the vicinity of the air diffuser 22 from being dried, to suppress the generation of deposits, and a special air diffuser cleaning mechanism, a cleaning chemical, and a cleaning process are not required.

The schematic diagram of the diffuser provided with the nozzle which is Example 1 of the present invention. The schematic diagram of a membrane separation activated sludge processing apparatus. The schematic diagram of the diffuser provided with the sliding body which is Example 2 of this invention. The schematic diagram of the diffuser provided with the valve mechanism which is Example 3 of this invention. The schematic diagram of the diffuser provided with the fluid heating apparatus for washing | cleaning which is Example 4 of this invention. The schematic diagram of the diffuser provided with the bubble production | generation sensor which is Example 5 of this invention. The schematic diagram of the signal which a bubble production | generation sensor outputs. The schematic diagram of the membrane separation activated sludge processing apparatus provided with the monitoring apparatus of the aeration apparatus which is Example 5 of this invention. The schematic diagram of the diffuser provided with the humidification apparatus which is Example 6 of this invention. The schematic diagram of the diffuser provided with the cooling mechanism which is Example 7 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Aeration pipe 12 Aeration hole 14 Aeration pipe connection port 16 Nozzle 18 Cleaning fluid piping 20 Cleaning fluid 22 Aeration air 24 Reaction tank 26 Water to be treated 28 Flat membrane 30 Piping 32 Aeration device 34 Sliding body 36 Sliding body drive Device 38 Valve mechanism 40 Valve mechanism driving device 42 Cleaning fluid heating device 44 Cleaning fluid injection device 46 Cleaning fluid 48 Aeration tube communication piping 50 Bubble generation sensor 52 Aeration device monitoring device 54 Bubble generation information 56 Humidification device 58 Cooling mechanism

Claims (17)

  A diffuser tube that is immersed in the reaction vessel and has a plurality of diffuser holes, an injection device that sends air to diffuse into the diffuser tube, and an attachment of the diffuser holes provided in the diffuser tube An air diffuser comprising a peeling and removing unit.   A separation / removal part for the adhered matter is provided in the aeration pipe, a cleaning fluid pipe through which the cleaning fluid flows, a cleaning fluid injection device for injecting the cleaning fluid into the cleaning fluid pipe, The aeration apparatus according to claim 1, wherein the aeration apparatus is configured by a nozzle that is disposed in a trachea and that ejects a cleaning fluid toward the aeration holes.   2. The depositing / removing part is disposed in the diffuser tube, and is configured by a sliding body that mechanically removes the deposits of the diffuser holes and a sliding body driving device that drives the sliding body. The air diffuser described in 1.   The adhering material peeling / removal part is disposed in the air diffuser and includes a valve mechanism that closes some air holes or reduces the effective area of the air diffuser, and a valve mechanism driving device that drives the valve mechanism. The aeration apparatus according to claim 1.   A diffuser tube that is immersed in the reaction vessel and has a plurality of diffuser holes, an injection device that sends air to diffuse into the diffuser tube, a washing fluid heating device that generates hot water or water vapor, An air diffuser comprising: a cleaning fluid injection device that injects hot water or water vapor generated by the cleaning fluid heating device into the air diffusion pipe.   A diffuser tube having a plurality of diffuser holes arranged soaked in a reaction vessel, an injection device for sending air to diffuse into the diffuser tube, and water vapor or mist-like water particles in the diffuser tube A humidifying device for infusing;   A diffuser tube having a plurality of diffuser holes arranged so as to be immersed in the reaction tank, an injection device for sending air to diffuse into the diffuser tube, and cooling for cooling the air diffused in the diffuser tube An air diffuser comprising a mechanism.   The aeration apparatus according to claim 1, further comprising a bubble generation sensor that is disposed outside the diffusion tube in the plurality of diffusion holes and measures a physical quantity related to bubble generation.   A plurality of flat membranes immersed in the reaction vessel, a pipe for taking out the treated water membrane-filtered by the flat membrane, a diffuser tube installed below the plurality of flat membranes and having a plurality of air holes A reaction tank comprising: an injection device for sending air for diffusing into the air diffusing tube; and an air diffusing device provided in the air diffusing tube and having a separation / removal part for deposits on the air diffusing holes.   A separation / removal part for the adhered matter is provided in the aeration pipe, a cleaning fluid pipe through which the cleaning fluid flows, a cleaning fluid injection device for injecting the cleaning fluid into the cleaning fluid pipe, The reaction tank according to claim 9, wherein the reaction tank is configured by a nozzle that is disposed in a trachea and that ejects a cleaning fluid toward the diffuser holes.   The peeling and removing portion of the deposit is disposed in the diffuser tube, and is configured by a sliding body that mechanically removes the deposit on the diffuser and a sliding body driving device that drives the sliding body. The reaction tank described in 1.   The adhering material peeling / removal part is disposed in the air diffuser and includes a valve mechanism that closes some air holes or reduces the effective area of the air diffuser, and a valve mechanism driving device that drives the valve mechanism. The reaction vessel according to claim 9.   A plurality of flat membranes immersed in the reaction vessel, a pipe for taking out the treated water membrane-filtered by the flat membrane, a diffuser tube installed below the plurality of flat membranes and having a plurality of air holes An injection device for sending air to diffuse into the diffuser tube, a cleaning fluid heating device for generating hot water or steam, and hot water or steam generated by the cleaning fluid heating device into the diffuser tube An air diffuser having a cleaning fluid injection device for injection.   A plurality of flat membranes immersed in the reaction vessel, a pipe for taking out the treated water membrane-filtered by the flat membrane, a diffuser tube installed below the plurality of flat membranes and having a plurality of air holes A reaction tank comprising: an infusion device for sending air for aeration into the aeration tube; and an aeration device having a humidifier for injecting water vapor or mist-like water particles into the aeration tube.   A plurality of flat membranes immersed in the reaction vessel, a pipe for taking out the treated water membrane-filtered by the flat membrane, a diffuser tube installed below the plurality of flat membranes and having a plurality of air holes A reaction tank comprising: an injection device that sends air for diffusing into the diffusing tube; and a diffusing device that has a cooling mechanism that cools the air diffusing into the diffusing tube.   The plurality of air diffusion holes are provided outside the air diffusion pipe and include a bubble generation sensor that measures a physical quantity related to bubble generation. A physical quantity related to the bubbles generated from the air diffusion holes by receiving a signal from the bubble generation sensor The reaction tank according to any one of claims 9 to 15, further comprising a display device that displays the value using numerical values or figures.   The reaction vessel according to claim 16, further comprising a cleaning execution timing determination unit that determines a cleaning execution timing based on a measurement value of the bubble generation sensor.

Images