JP5763503B2 - Moving bed type upflow continuous sand filtration device and operation method thereof - Google Patents

Description

  The present invention relates to a moving bed type upflow continuous sand filtration apparatus and an operation method thereof.

  In general, a moving bed type upflow continuous sand filtration device is widely used as a device that can simultaneously filter all kinds of water such as clean water, sewage, and industrial wastewater and wash the filtered sand.

  FIG. 6 shows an example of a conventional moving bed type upflow continuous sand filtration apparatus, in which a filtration layer 1 filled with a filter medium such as sand and a raw water supply for supplying raw water to the bottom of the filtration layer 1 are shown. Means 2, filtered water recovery means 3 that is supplied from the raw water supply means 2 to the bottom of the filtration layer 1 and that is filtered by raising the inside of the filtration layer 1 to collect and extract as filtered water, and the raw water The suspended solid (SS: Suspended Solid) was collected from the bottom of the filter layer 1 with the air rising from the bottom of the filter layer 1 and separated from the filter medium. And a filter medium cleaning means 4 for returning the filter medium to the filter layer 1.

  The raw water supply means 2 is provided at the bottom of the filtration tank 5 with a plurality of raw water supply nozzles 2b extending upward from the raw water supply header 2a so as to open into the filtration layer 1, and each of the raw water supply nozzles 2b. The upper end opening is covered and a filtration tank 5 and a concentric annular distributor 2c are disposed.

  The filtered water recovery means 3 includes a weir 3a that overflows the filtered supernatant water by ascending the inside of the filtration layer 1 at a required position on the outer periphery of the upper portion of the filtration tank 5, and a supernatant water that has passed over the weir 3a. A filtered water receiving portion 3c is formed by the receiving plate 3b, and a filtered water nozzle 3d is connected to the filtered water receiving portion 3c.

  The filter medium cleaning means 4 is arranged at the center of the filter layer 1 so as to extend in the vertical direction an air lift pipe 4a that conveys the filter medium with the air rising from the bottom of the filter layer 1, and the upper end of the air lift pipe 4a. In addition, a drainage basin 4b that receives the filter medium overflowing from its upper end and divides it into cleaning wastewater and filter medium is provided, and an airlift cleaning drainage pipe 4c for extracting the cleaning wastewater is connected to the drainage basin 4b. . At the center of the air lift pipe 4a, an air introduction pipe 4d for supplying air from above the filtration tank 5 is disposed to form a double pipe structure, and at the bottom of the drainage basin 4b, the air lift pipe 4a is provided. A filter medium return pipe 4e, which is concentrically disposed on the upper outer periphery of the tube and has a labyrinth space formed therein, is connected.

  In the moving bed type upward flow continuous sand filtration apparatus as described above, the raw water supplied to the raw water supply header 2a is supplied from the raw water supply nozzle 2b constituting the raw water supply means 2 as shown in FIG. The suspended material is blown out from the upper end opening to the filtration layer 1 and is evenly distributed over the entire area of the filtration layer 1 by the distributor 2c. It is removed and becomes clean filtrate, overflows the weir 3a constituting the filtrate collection means 3, flows into the filtrate receiver 3c, and is discharged from the filtrate nozzle 3d.

  At the same time, as shown in FIG. 6 (b), the filter medium that has captured suspended substances from the raw water is air lift pipe together with air supplied from the air introduction pipe 4 d constituting the filter medium cleaning means 4 to the bottom of the filter layer 1. 4a is sucked into the inside of the air lift pipe 4a and the inside of the air lift pipe 4a rises at a different speed between the filter medium, water and air, so that the filter medium is trapped and the suspended substances are separated from the filter medium. The filter medium overflowing from the upper end is separated from washing wastewater containing suspended solids inside the drainage basin 4b, and the washing wastewater is extracted from the washing drainage pipe. The suspended matter remaining in the labyrinth space is further separated while flowing down the return pipe 4 e and returned to the filtration layer 1.

  In FIG. 6, reference numeral 6 denotes a conical filter medium guide means disposed at the bottom of the filter layer 1 so as to surround the air lift pipe 4 a. The conical filter medium guide means 6 allows the filter layer 1 to be viewed from above. The filter medium flowing down is evenly distributed over the entire cross section of the filter tank 5, and the filter medium below the conical filter medium guide means 6 is directly consolidated by the weight of the filter medium above the conical filter medium guide means 6. This prevents it from becoming difficult to flow. Furthermore, bubbles generated in the filtration layer 1 are captured and discharged to the outside from a bubble discharge pipe (not shown) connected to the upper part of the conical filter medium guiding means 6.

  The moving bed type upward flow continuous sand filtration device is a filtration module M in which the filtration layer 1, raw water supply means 2, filtered water recovery means 3 and filter medium washing means 4 are combined as one minimum unit, In general, a plurality of filtration tanks 5 in which the filtration module M is built are disposed according to the amount of raw water treated. In this case, as shown in FIG. The air lift cleaning drain pipe 4c of the filtration module M is connected to the cleaning drain collecting pipe 7, and the cleaning drain from each of the filtration tanks 5 is sent to the cleaning drain tank not shown in the form of being combined in the cleaning drain collecting pipe 7. It has become. In addition, with respect to each said filtration tank 5, raw | natural water is supplied in the form distributed by one pump from the raw | natural water tank which is not shown in figure.

  Incidentally, the moving bed type upward continuous sand filtration apparatus shown in FIGS. 6 and 7 is a so-called filtration tank 5 manufactured by a steel plate, and a single filtration module M is built in one filtration tank 5. Although there is a single filtration module type, there is also one in which the filtration tank 5 is made of concrete. In this case, as shown in FIG. 8, a plurality of filtration modules M are built in one filtration tank 5. There is a so-called multi-filtration module type, and the air lift cleaning drain pipe 4c of each filtering module M is connected to the cleaning drain tank 7 via a connecting pipe 4f disposed inside the filtering tank 5. To be connected to. Needless to say, the filtration tank 5 shown in FIGS. 6 and 7 can be made of concrete, or the filtration tank 5 shown in FIG. 8 can be made of a steel plate.

  In addition, there exist patent document 1, 2 as what shows the general technical level relevant to the said moving bed type upflow continuous sand filtration apparatus, for example.

Japanese Patent Publication No. 56-51808 Japanese Patent No. 3853738

  However, in the conventional moving bed type upflow continuous sand filtration apparatus as described above, for example, the concentration of suspended substances becomes abnormally high, or there are many substances that are easily fixed to the filter medium such as sand. Thus, when the properties of the incoming raw water are changed, a solidified portion is formed in the filtration layer 1 and the circulating movement of the filter medium becomes insufficient, the pressure loss when the raw water is filtered increases, and the turbidity of the filtered water also increases. It was necessary to take some measures promptly.

  In the event of an emergency requiring such an emergency response, the raw water is supplied from the raw water supply nozzle 2b for the purpose of clogging and washing, and the mass produced in the filtration layer 1 is removed from the high pressure water from above the filtration layer 1. It is effective to directly pulverize and agitate by jetting, etc., but when such pulverization and agitation are performed, water containing a large amount of suspended matter passes through the weir 3a and is discharged from the filtered water nozzle 3d. For this reason, there is a risk that clean filtered water filtered before clogging washing is contaminated with suspended substances. Therefore, for example, a temporary forced drain pipe has to be branched and connected from a filtered water pipe (not shown) connected to the filtered water nozzle 3d to collect water containing the suspended solids. However, branch connection of the temporary forced drain pipe from the filtered water pipe has a problem that it takes time for preparation and complicated work is required.

  Further, in order to prevent the water containing a large amount of suspended matter from being discharged from the filtered water nozzle 3d beyond the weir 3a, an amount corresponding to the flow rate of the cleaning wastewater that can be discharged from the air lift cleaning drain pipe 4c. Although it is possible to supply the raw water little by little from the raw water supply nozzle 2b for clogging cleaning, in this case, it takes a very long time to complete clogging cleaning, and it cannot be said that it is a very preferable measure.

  Furthermore, it is possible to insert a submersible pump above the filtration layer 1 and forcibly pump up and collect the water containing the suspended solids with the submersible pump. It was inevitable that it would be troublesome, and it could not be said that it was a preferable measure.

  Note that neither Patent Documents 1 and 2 describe any clogging cleaning in an emergency that requires an emergency.

  In view of such circumstances, the present invention discharges water containing a large amount of suspended matter from the filtered water recovery means when clogging occurs in the filtration modules built in the plurality of filtration tanks connected to the washing drainage collecting pipe. It is an object of the present invention to provide a moving bed type upflow continuous sand filtration apparatus that can easily and efficiently perform clogging washing and an operation method thereof.

The present invention includes a filtration layer filled with a filter medium, raw water supply means for supplying raw water to the bottom of the filtration layer, and supplied from the raw water supply means to the bottom of the filtration layer and rising in the filtration layer. Filtered water recovery means for collecting and removing the filtered supernatant water as filtered water, and transporting the filter medium capturing the suspended solids from the raw water together with the rise of air from the bottom of the filter layer to separate the suspended substances from the filter medium and wash them Moving bed type up-flow continuous sand filtration comprising a plurality of filtration tanks having a filtration medium cleaning means for collecting and removing as a waste water and returning a filtration medium from which suspended substances are separated to a filtration layer. In the device
An air lift pipe arranged to extend in the vertical direction at the center of the filtration layer and carrying the filter medium along with the rise of air from the bottom of the filtration layer; It consists of a drainage basin that receives the filter medium overflowing from the upper end of the airlift pipe and divides it into washing wastewater and filter medium, and an airlift washing drainage pipe that extracts the cleaning wastewater from the drainage tank,
The air lift cleaning drain pipe of the filtration module built in each filtration tank is connected to the cleaning drain collection pipe, and the filtered water is collected when the filtration module built in each filtration tank is clogged with the washing drain collection pipe. A moving bed type upflow continuous sand filtration device characterized in that a clogging drainage pipe for discharging water between the recovery means and the filtration layer is connected, and an opening / closing means is provided in each clogging washing drainage pipe. Is.

  According to the above means, the following operation can be obtained.

  For example, if the concentration of suspended solids is abnormally high, or there are many substances that easily adhere to filter media such as sand, and the properties of the incoming raw water change, a solidified part will occur in the filtration layer. Therefore, the circulating movement of the filter medium becomes insufficient, the pressure loss when the raw water is filtered increases, and the turbidity of the filtered water may increase, so the raw water is supplied from the raw water supply means to the filtration layer. The resulting lump is clogged and washed by directly crushing and stirring by jetting high-pressure water or the like.When the clogging washing is performed, if the opening / closing means of the filtration tank containing the clogged filtration module is opened, Since the drainage operation is performed from the clogging washing drain pipe of the filtration tank in which the filtration module is built in, it is avoided that water containing a large amount of suspended matter is discharged from the filtrate collection means, and each filtration tank is In contrast, Since the raw water is supplied from the water tank by a single pump, the raw water filtration and the filter medium cleaning are performed simultaneously in the filtration tanks other than the filtration tank in which the clogged filtration module is built. The normal operation that is proceeding will continue.

  As a result, unlike conventional cases, for example, a temporary forced drain pipe is branched from a filtered water pipe connected to the filtered water collecting means, and clogging is generated unlike the case where water containing the suspended substance is collected. By simply opening the opening / closing means of the filtration tank in which the filtration module is built in, preparation is not time-consuming and no complicated work is required.

  In addition, in order to prevent the water containing a large amount of suspended solids from being discharged from the filtered water recovery means, the raw water in an amount corresponding to the flow rate of the cleaning drainage that can be discharged from the airlift cleaning drainpipe is gradually clogged for cleaning. As compared with the case of supplying from the raw water supply means, it is possible to shorten the time until clogging cleaning is completed.

  Furthermore, unlike the case where a submersible pump is inserted above the filtration layer and the water containing the suspended solids is forcibly pumped up and collected by the submersible pump, troublesome work such as arranging a submersible pump is also required. You don't have to do it.

  In the moving bed type upflow continuous sand filtration apparatus, the inner diameter of the clogging drainage pipe is set to a value that allows drainage at a flow rate corresponding to the raw water supply flow rate of each filtration tank, based on a preset pipe flow velocity. At the same time, the inner diameter of the washing drainage collecting pipe can be set to a value that allows drainage at a flow rate that matches the total raw water supply flow rate of each filtration tank, based on a preset flow velocity in the pipe.

Further, the present invention is an operation method of the moving bed type upward flow continuous sand filtration device,
Opening and closing means of the clogged filtration tank is opened, drainage work is performed from the clogging washing drain pipe of the filtration tank, and raw water filtration and filter medium washing in the filtration tank other than the clogged filtration tank are simultaneously performed. The present invention relates to a method for operating a moving bed type upflow continuous sand filtration device characterized by continuing normal operation.

  According to the moving bed type upflow continuous sand filtration apparatus of the present invention and the operation method thereof, when clogging occurs in the filtration modules built in a plurality of filtration tanks connected to the washing drainage collecting pipe, suspended substances are removed. While preventing a large amount of water from being discharged from the filtered water recovery means, it is possible to achieve an excellent effect that clogging cleaning can be performed easily and efficiently.

It is a schematic plan view which shows the 1st Example of the moving bed type upward flow continuous sand filtration apparatus of this invention. It is a schematic sectional drawing which shows the filtration module incorporated in the filtration tank in the 1st Example of the moving bed type upward flow continuous sand filtration apparatus of this invention. It is a schematic plan view which shows the 2nd Example of the moving bed type upward flow continuous sand filtration apparatus of this invention. It is a schematic sectional drawing which shows the filtration module incorporated in the filtration tank in the 2nd Example of the moving bed type upward flow continuous sand filtration apparatus of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic which shows the modification of the opening-and-closing means of the clogging washing | cleaning drain pipe in the 1st Example of the moving bed type upward flow continuous sand filtration apparatus of this invention, and a 2nd Example, (a) is a clogging washing | cleaning drainage pipe. The figure which shows the example which screws the stopper made from elastic bodies, such as rubber | gum, into the opening of FIG., (B) is the figure which shows the example which attaches the lid pressed by the hydraulic pressure to the opening of the clogging washing drain pipe, (c) is the figure of the clogging washing drain pipe It is a figure which shows the example which provides the bellows which can be pulled up to a position above a water surface along a support | pillar in opening. It is a schematic sectional drawing which shows an example of the conventional moving bed type upflow continuous sand filtration apparatus, (a) is a principle explanatory drawing of raw water filtration, (b) is a principle explanatory drawing of filter medium washing | cleaning. It is a schematic plan view which shows an example of the conventional moving bed type upflow continuous sand filtration apparatus which arrange | positioned the plurality of steel-plate filtration tanks in which the filtration module was incorporated. It is a schematic plan view which shows an example of the conventional moving bed type upflow continuous sand filtration apparatus which arrange | positioned the plurality of concrete filtration tanks in which the filtration module was incorporated.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 and 2 show a first embodiment of the moving bed type upward flow continuous sand filtration device of the present invention (the filtration tank 5 is made of a steel plate), which is the same as FIG. 6 and FIG. The parts denoted by the reference numerals represent the same thing, and the basic configuration is the same as the conventional one shown in FIGS. 6 and 7, but the feature of the first embodiment is that shown in FIGS. 2, when the clogging occurs in the filtration module M built in each filtration tank 5 with respect to the washing drainage collecting pipe 7 disposed outside each filtration tank 5, the filtered water recovery means 3, the filtration layer 1, A clogging drainage pipe 8 for discharging water between them is connected, and an opening / closing means 9 is provided for each clogging drainage pipe 8.

  In the case of the first embodiment, the opening / closing means 9 is a valve 9a which is kept closed during normal operation and opened when clogging occurs. As for opening and closing of the valve 9a, either a manual type or a remote control type can be selected.

Here, regardless of whether it is a single filtration module type or a multiple filtration module type, the number of filtration tanks 5 is N (N = 3 in the example of FIG. 1), and the number of filtration tanks 5 in which clogging has occurred. Is n (n ≦ N), and the raw water supply flow rate to each filtration tank 5 is Q [m ³ / s], respectively, the washing drainage flow rate from the air lift washing drainage pipe 4c during normal operation (single filtration module type) In this case, the cleaning drainage flow rate from one airlift cleaning drainage pipe 4c, but in the case of the multi-filtration module type, the total cleaning drainage flow rate from a plurality of airlift cleaning drainage pipes 4c) is 5 of the raw water supply flow rate. Since it is desirable to set it to ˜15 [%], when m = 0.05 to 0.15, the washing waste water flow rate is
mQ
On the other hand, in the filtration tank 5 in which clogging has occurred, in order to prevent the turbid filtrate from being discharged from the filtrate collection means 3, the same amount of water as the raw water supply flow rate is clogged and washed and drained. It is necessary to flow out from the cleaning drainage collecting pipe 7.

Therefore, when the clogging in filtering tank 5 of n units occurs, the cleaning waste water flow through the wash water discharge collecting pipe 7 When q _n,
[Equation 1]
q _n = nQ + mQ (N−n)
When the inner diameter of the cleaning drainage collecting pipe 7 is d [m], the internal cross-sectional area of the cleaning drainage collecting pipe 7 is
πd ^2/4
Therefore, when the flow velocity in the washing drainage collecting pipe 7 is v [m / s] (generally, v = 0.2 to 0.5), the inner diameter of the washing drainage collecting pipe 7 is
d = 2 × (q _n / πv) ^1/2
It becomes. In the case of the multi-filtration module type, the raw water supplied to the filtration tank 5 (raw water supply flow rate Q) is distributed to each filtration module, and if the number of filtration modules in the multi-filtration module type is j, Since the distribution raw water supply flow rate Q ′ supplied to the filtration module is Q ′ = Q / j and Q = jQ ′, the above [Equation 1] is
q _n = njQ ′ + mjQ ′ (N−n)
Can also be expressed.

Incidentally, since the washing drainage flow rate q _n becomes maximum when n = N, the maximum washing drainage flow rate q _n (flow rate corresponding to the sum of the raw water supply flow rates Q of the respective filtration tanks 5) can be flowed. The inner diameter d of the cleaning / drainage collecting pipe 7 may be set. However, when the inner diameter d of the cleaning drainage collecting pipe 7 is set in this way, the diameter of the cleaning drainage collecting pipe 7 increases as the number N of the filtration tanks 5 increases. In actual operation, for example, if three filtration tanks 5 are clogged at the same time, the clogging and cleaning are performed one by one. This also becomes one countermeasure, and in this way, it is avoided that the diameter of the washing drainage collecting pipe 7 becomes so thick that it becomes impossible to realize, and problems of personnel and tools for clogging washing are also solved. . Further, the inner diameter d ′ of the clogging washing drain pipe 8 may be set to a value that allows drainage at a flow rate that matches the raw water supply flow rate Q of each filtration tank 5 based on the preset pipe flow velocity v.

  Next, the operation of the first embodiment will be described.

  For example, when the concentration of suspended solids is abnormally high, or there are many substances that are likely to adhere to the filter medium such as sand, and the properties of the incoming raw water change, the solidified portion of the filtration layer 1 As a result, the circulating movement of the filter medium becomes insufficient, the pressure loss when the raw water is filtered is increased, and the turbidity of the filtered water may be increased. Therefore, while supplying the raw water from the raw water supply nozzle 2b, the filtration is performed. The clogging washing which crushes and stirs the lump part generated in the layer 1 directly by jetting high-pressure water or the like is performed. When the valve 9a is opened, the drainage work is performed from the clogging washing drain pipe 8 of the filtration module M built in the filtration tank 5, so that water containing a large amount of suspended substances passes through the weir 3a and passes through the filtered water nozzle. It was discharged from 3d In addition, the clogging is generated because the raw water is supplied to each filtration tank 5 from a raw water tank (not shown) by a single pump. In the filtration tanks 5 other than the filtration tank 5 in which the filtration module M is incorporated, the normal operation in which the raw water filtration and the filter medium cleaning are simultaneously performed is continuously performed.

  Thereby, for example, a conventional forced drainage pipe is branched and connected from a filtered water pipe (not shown) connected to the filtered water nozzle 3d as in the prior art, and the water containing the suspended substance is recovered. In contrast, simply opening the valve 9a of the opening / closing means 9 of the filtration tank 5 in which the filtration module M in which clogging has occurred is not required for preparation, and no complicated work is required.

  Further, in order to avoid the water containing a large amount of suspended matter from being discharged from the filtered water nozzle 3d beyond the weir 3a, the raw water in an amount corresponding to the flow rate of the cleaning wastewater that can be discharged from the airlift cleaning drain pipe 4c. As compared with the case where the water is supplied from the raw water supply nozzle 2b for clogging cleaning little by little, the time until clogging cleaning is completed can be shortened.

  Furthermore, unlike the case where a submersible pump is inserted above the filtration layer 1 and the water containing the suspended solids is forcibly pumped up and collected by the submersible pump, troublesome work such as arranging a submersible pump. You do n’t have to.

  Thus, when clogging occurs in the filtration module M built in the plurality of filtration tanks 5 connected to the washing drainage collecting pipe 7, the water containing a large amount of suspended matter passes over the weir 3 a of the filtrate collection means 3. The clogging cleaning can be easily and efficiently performed while preventing the filtered water nozzle 3d from being discharged.

  3 and 4 show a second embodiment of the moving bed type upward flow continuous sand filtration apparatus of the present invention (the filtration tank 5 is made of concrete), and the same reference numerals as those in FIG. These parts represent the same thing, and the basic structure is the same as that of the conventional one shown in FIG. 8, but the feature of the second embodiment is that filtration is performed as shown in FIG. 3 and FIG. When the clogging occurs in the filtration module M built in each filtration tank 5 with respect to the connecting pipe 4f disposed inside the tank 5 and connected to the washing drainage collecting pipe 7, the filtered water recovery means 3 and the filtration layer 1 The clogging washing drain pipes 8 for discharging water between the clogging washing drain pipes 8 are connected, and the clogging washing drain pipes 8 are provided with an opening / closing means 9 (valve 9a).

  In the case of this 2nd Example, as shown in FIG. 4, the raw | natural water supply header 2a extends so that each filtration module M may be penetrated inside the filtration tank 5, and each filtration module M is penetrated also about the filtrate water receiving part 3c. The raw water supply nozzle 2b is extended downward from the raw water supply header 2a and connected to the distributor 2c. The distributor 2c is disposed concentrically on the outer periphery of the air lift pipe 4a and A center pipe 2d to which the raw water supply nozzle 2b is connected, and a plurality of raw water dispersion guides 2e extending radially like an umbrella bone around the center pipe 2d and having an opening on the lower surface side. In addition, the single filtration module in which the filtration tank 5 shown in FIG. 1 and FIG. Those with structures Yurutaipu are different, the principles of the raw water is filtered and the filter media cleaning has become exactly the same.

  Also in the second embodiment, for example, when the concentration of suspended solids is abnormally high, or there are many substances that are likely to adhere to filter media such as sand, and the properties of the incoming raw water have changed. Since the solidified portion is generated in the filter layer 1 and the circulating movement of the filter medium is insufficient, the pressure loss when filtering the raw water is increased, and the turbidity of the filtered water may be increased. While the clogging cleaning is performed by directly crushing and stirring the lump portion generated in the filtration layer 1 by jetting high-pressure water or the like while supplying from the nozzle 2b, the filtration module M in which clogging has occurred is built in the clogging cleaning. When the valve 9a of the opening / closing means 9 of the filtration tank 5 is opened, the drainage operation is performed from the clogging washing drain pipe 8 of the filtration tank 5 in which the filtration module M is built, so that water containing a large amount of suspended substances is contained. Filtered water over the weir 3a In the filtration tanks 5 other than the filtration tank 5 in which the clogged filtration module M is built in, the normal operation in which the raw water filtration and the filter medium cleaning are simultaneously performed continues. Will be performed.

  Thereby, for example, a conventional forced drainage pipe is branched and connected from a filtered water pipe (not shown) connected to the filtered water nozzle 3d as in the prior art, and the water containing the suspended substance is recovered. Unlike the first embodiment, only the valve 9a of the opening / closing means 9 of the filtration tank 5 containing the clogged filtration module M is opened, so that preparation is not required and no complicated work is required. In addition, in order to avoid that the water containing a large amount of suspended matter passes through the weir 3a and is discharged from the filtered water nozzle 3d, it is commensurate with the flow rate of the cleaning wastewater that can be discharged from the air lift cleaning drain pipe 4c. Compared to supplying a quantity of raw water little by little from the raw water supply nozzle 2b for clogging cleaning, it is possible to shorten the time until clogging cleaning is completed, and a submersible pump is provided above the filtration layer 1. Throw in, Unlike in water pump to collect pumped to force the water containing the suspended matter, need not take place even troublesome work arrangements such as the submersible pump.

  Thus, also in the second embodiment, as in the first embodiment, when clogging occurs in the filtration module M built in the plurality of filtration tanks 5 connected to the washing drainage collecting pipe 7, a large amount of suspended matter is contained. It is possible to easily and efficiently perform clogging cleaning while preventing water from passing through the weir 3a of the filtered water recovery means 3 and being discharged from the filtered water nozzle 3d. In addition, it cannot be overemphasized that what manufactured the filtration tank 5 as shown in FIG.3 and FIG.4 with concrete may be made into a single filtration module type instead of a multi-filtration module type.

  Incidentally, in the first and second embodiments, the opening / closing means 9 of the clogging drainage pipe 8 is a valve 9a. For example, as shown in FIG. With the opening facing upward, a stopper 9b made of an elastic material such as rubber is screwed into the opening, or as shown in FIG. 5B, a lid 9c that is pressed against the opening of the clogging washing drain pipe 8 by water pressure is attached. Alternatively, or as shown in FIG. 5 (c), the valve 9a can be provided by providing a bellows 9e that can be pulled up to a position above the water surface along the column 9d at the opening of the clogging drain pipe 8. As an alternative to this, it is possible to configure the opening / closing means 9.

  In addition, the moving bed type upward flow continuous sand filtration apparatus and the operation method thereof according to the present invention are not limited to the above-described embodiments, and the number of filtration modules built in the filtration tank can be appropriately selected. Of course, the filtration tank can be made of either steel plate or concrete regardless of the single filtration module type or the multi-filtration module type, and other various modifications can be made without departing from the scope of the present invention. It is.

DESCRIPTION OF SYMBOLS 1 Filtration layer 2 Raw water supply means 3 Filter water collection means 4 Filter medium washing means 4a Air lift pipe 4b Drainage basin 4c Air lift washing drain pipe 5 Filtration tank 7 Washing drain collecting pipe 8 Clogging washing drain pipe 9 Opening and closing means M Filtration module

Claims (3)

A filtration layer filled with a filter medium, raw water supply means for supplying raw water to the bottom of the filtration layer, and filtered by being supplied from the raw water supply means to the bottom of the filtration layer and rising in the filtration layer Filtered water recovery means for collecting and removing the clear water as filtered water, and the filter medium capturing the suspended matter from the raw water is transported along with the rise of air from the bottom of the filter layer, separating the suspended substance from the filter medium and collecting it as washing waste water. In the moving bed type upflow continuous sand filtration apparatus, in which a plurality of filtration tanks including a filtration medium cleaning means having a filtration medium cleaning means for returning the filtration medium from which suspended substances are separated and returned to the filtration layer are provided,
An air lift pipe arranged to extend in the vertical direction at the center of the filtration layer and carrying the filter medium along with the rise of air from the bottom of the filtration layer; It consists of a drainage basin that receives the filter medium overflowing from the upper end of the airlift pipe and divides it into washing wastewater and filter medium, and an airlift washing drainage pipe that extracts the cleaning wastewater from the drainage tank,
The air lift cleaning drain pipe of the filtration module built in each filtration tank is connected to the cleaning drain collection pipe, and the filtered water is collected when the filtration module built in each filtration tank is clogged with the washing drain collection pipe. A moving bed type upflow continuous sand filtration apparatus, wherein a clogging drainage pipe for discharging water between the recovery means and the filtration layer is connected, and an opening / closing means is provided in each clogging washing drainage pipe.   The inside diameter of the clogging drainage pipe is set to a value that allows drainage at a flow rate that matches the raw water supply flow rate of each filtration tank based on a preset pipe flow rate, and the inside diameter of the washing drainage collection pipe is set in advance. The moving bed type upflow continuous sand filtration apparatus according to claim 1, wherein the drainage is allowed to flow at a flow rate commensurate with the sum of the raw water supply flow rates of the filtration tanks based on the pipe flow velocity. An operation method of the moving bed type upward flow continuous sand filtration device according to claim 2,
Opening and closing means of the clogged filtration tank is opened, drainage work is performed from the clogging washing drain pipe of the filtration tank, and raw water filtration and filter medium washing in the filtration tank other than the clogged filtration tank are simultaneously performed. The operation method of the moving bed type upflow continuous sand filtration device characterized by continuing normal operation.

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