JPH02107304A - Filtering apparatus - Google Patents

Abstract

PURPOSE:To ensure the prevention of the outflowing of filter material accompanied by the movement of the filter material due to the flowing liquid at the time of cleaning by automatically creating a siphonage making use of the lowering of the water level of a tank and bringing down the water level to a sufficiently lower predetermined elevation than that of a back washing drain conduit before air cleaning. CONSTITUTION:A tank 1 is divided by a vertical separating wall 2 into a drain 3 and a filter chamber 5 constituting a filter material layer. A back washing drain conduit 6, provided in the filter chamber 5, is communicated with the drain 3. A drain outlet conduit 8 provided outside the tank 1 is communicated with the drain 3 through a drain siphon 9 capable of the formation and destruction of the siphonage. A siphon forming pipe 3 is provided which has one end thereof placed open between the drain conduit 6 and the filter material layer 4 and the other end thereof placed open in the drain siphon 9 at an elevation above the high water level of the tank 1 and which is fitted with a drain siphon destruction valve 14. As a result, at automatic siphone is formed using the lowering of the water level of the tank 1 and the water level is lowered to a predetermined water level of the tank, ensuring the prevention of the flowing out of the filter material at the time of cleaning.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a siphon-type gravity filtration device that performs air cleaning for filtering and purifying clean water, industrial water, and other liquids.

[Conventional technology]

In gravity filtration devices, in order to renew the filter layer whose filtration resistance has increased due to the accumulation of turbidity captured during filtration, air cleaning is performed by pressurizing air from the bottom of the filter layer and fluidizing and agitating the filter layer. ing.

If the water level in the tank is not lowered sufficiently below the top of the backwash drain gutter before cleaning the filter layer, the water surface will expand due to the injected air and the fluidized furnace material will be backwashed. It will flow into the drainage gutter and cause loss of furnace material.

For this purpose, mechanical and electrical control devices were attached to the filtration device, and special operations were performed to lower the water level in the tank.

In addition, in order to make such control devices and operations as simple as possible, as shown in Japanese Utility Model Publication No. 60-22964, an intermediate drain pipe equipped with a drain valve is provided between the backwash drain gutter and the filter layer. Something was also devised.

[Problem to be solved by the invention]

However, conventional control devices for lowering the water level in the tank sufficiently below the backwash drainage gutter are structurally complex and inconvenient in handling and maintenance.

Furthermore, the method disclosed in the above-mentioned Japanese Utility Model Publication No. 60-22964 also uses a motor-operated valve to make the drain valve easier to operate, since the drain valve is opened and closed more frequently due to relatively frequent cleaning of the filter layer. However, the control becomes complicated and often causes failures.

The present invention solves the above-mentioned conventional problems and automatically forms a wastewater siphon by utilizing the drop in water level in the tank without using any complicated control or special operation. It is an object of the present invention to provide a filtering device that can lower the water level to a predetermined tank water level and reliably prevent the outflow of wood during cleaning using air or a combination of air and water.

Furthermore, the present invention attempts to simplify the device and facilitate maintenance and management.

[Means to solve the problem]

In the present invention, the inside of the tank 1 is divided into a drain 3 and a filter layer 4 by a vertical partition wall 2, and a filter chamber 5, and a backwash drain gutter 6 is provided in the filter chamber 5 to drain the backwash water. The gutter 6 is connected to the drainage culvert 3, a drainage outflow culvert 8 is provided outside the tank 1, the drainage outflow culvert 8 and the drainage culvert 3 are communicated via a drainage siphon 9 that enables siphon formation and destruction, and the reverse is also established. Washing water v6 and filter layer 4
-v2 is opened in between, the other end is opened in the drain siphon 9 at a position above the high water level in the tank 1, and a waste water siphon forming pipe 13 is provided with a waste water siphon breaking valve 14 attached. It is a device with special features.

[For production]

In the present invention having the above configuration, when the raw water flows into the filter chamber 5 at the appropriate time, while it passes through the first material layer 4 due to gravity, the suspended matter in the raw water is captured and becomes clarified water, which becomes filter material. It flows out from the bottom of layer 4.

When cleaning this filter medium layer 4, the flow of raw water into the filtration chamber 5 is stopped 2, and when the drainage siphon 9 is activated, the drainage culvert 3
The water level in the filtration chamber 5 drops to the same level as the upper end of the backwash drainage gutter 6. At that time, when the waste water siphon destruction valve 14 is closed, the waste water siphon forming pipe 1
The vacuum in the drain siphon tube 9 becomes the same as the vacuum in the drain siphon pipe 9, and the water below the backwash drain gutter 6 flows out from the drain siphon forming pipe 13 into the drain siphon 9 and is discarded into the drain S3. The water level in the menstrual chamber 5 drops to a certain level between the backwash drainage gutter 6 and the filter layer 4. Then, the wastewater siphon destruction valve 14 is opened to stop the wastewater siphon forming pipe 13 and the drainage siphon 9.

After that, when air for cleaning is injected into the lower part of the filter layer 4,
The filter medium layer 4 is fluidized and agitated to perform washing. During this air cleaning, the water surface expands due to the pressurized air, but the water level does not reach the upper end of the backwash drain gutter 6, and the furnace material does not flow into the backwash drain gutter 6. After performing this for a certain period of time, the suspended solids transfer water is introduced from the lower part of the iP material layer 4 and flows into the drain culvert 3 through the backwash drain trough 6, carrying only the separated suspended solids, and washes the furnace material N4. ends.

Further, when cleaning the filter medium layer 4 using both air and water, the amount of water is controlled so that the water does not reach the backwash drainage gutter 6.

After the cleaning of the filter layer 4 is completed, the drainage siphon 9 is activated again to transfer the cleaning wastewater that has flowed into the drain culvert 3 to the drainage outflow culvert 8, and the drainage siphon 9 is stopped to resume the above-mentioned drainage.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings. The inside of the tank 1 is divided into a drain 3 and a filter layer 4 formed by a vertical partition wall 2, and a filter chamber 5. A backwash drainage gutter 6 is provided and communicates with the drainage S3.

Adjacent to the outside of the tank 1 is a drainage outflow culvert 8 having an overflow wall 7, and this drainage outflow culvert 8 and the drainage culvert 3 in the tank 1 are communicated via a drainage siphon 9. A drain siphon forming pipe 11 containing a drain siphon forming valve 10 and a drain siphon breaking valve 12 are connected.

The drain chamber 5 and the inside of the drainage siphon 9 are communicated through a wastewater siphon forming pipe 13, and one end of this wastewater siphon forming pipe 13 is opened between the backwash drainage gutter 6 and the filter medium layer 4,
The other end is opened in the drain siphon 9 at a position above the tank high water level (HWL), and the drain siphon forming pipe 13 is also provided with a siphon break valve 14 .

Also, outside the tank l, there is a filtered water outflow conduit 16 having an overflow wall 15.
It is preferable that the two be adjacent to each other and communicated with the water collection chamber 17 formed at the bottom of the furnace material M4 in the tank 1.

Furthermore, one end of the filtered water outflow conduit 16 is connected to the water collection chamber 17 in the tank 1, and the other end is bent to allow an overflow wall 15 to flow upward.
A communication pipe 18 is opened below the top of the pipe, and near this open end, there is a communication pipe 18 with a plurality of holes, slits, etc. opened for controlling the amount of water flowing during washing, and a cylinder whose upper end is closed at the open end. Cover the cylindrical body 1 with a gap around the circumference using the body 19.
The bottom end of 9 is a hole.

A backflow siphon forming pipe 21 having a siphon breaker valve 20 is provided at the top of the cylinder 19 so as to be located below the slit etc. An air supply pipe 23 with a valve 22 is connected.

Reference numeral 24 indicates a cleaning air introduction pipe that includes an air valve 25 and is connected to the water collection chamber 17 in the tank 1.

In addition, as an inflow part for flowing raw water to be passed into the tank 1, the raw water inflow conduit 30 is divided into an inflow part 32 and an outflow part 33 by a vertical partition wall 31, and the outflow part 33 is connected to an overflow wall. 34
The inflow siphon 32 and the outflow 33 are connected to each other through an inflow siphon 35 and an inflow siphon forming pipe having an inflow siphon forming valve 36 at the top of the inflow siphon 35. 37 and an inflow siphon destruction valve 38 are connected.

Next, the operation procedure of the above embodiment will be explained with reference to FIGS. 1 to 6.

(1) Inflow siphon destruction valve 38 (see Figures 1 and 2) Closed inflow siphon formation valve 36
・−・−・・−・・−Open inflow siphon 35
Start-up drainage siphon destruction valve 14 Open drainage siphon formation valve 10 --- Closed drainage siphon destruction valve 12 Open drainage siphon 9
Stop air valve 25 ---
--------One-close siphon breaker valve 20
Open backflow siphon forming tube 21 Stop air valve 22
- When closed, raw water is introduced into the tank 1 from the inflow siphon 35 through the outflow part 33, passes through the filter layer 4 in a downward flow, turbidity in the raw water is captured by the filter layer 4, and the filtered water is The water reaches the water collection chamber 17 and flows out through the backflow siphon forming pipe 21 to the filtrate outflow @ 16 and the overflow wall 15
(see Figure 1).

However, as the filtration continues, the filter medium layer 4 increases the water flow resistance due to the captured suspended matter, and when it reaches a certain value and the water level in the tank 1 reaches a high water level (HIIL) (see Figure 2), the filtration is stopped. Stop.

(2) is overstopped (see Figure 3) Inflow siphon destruction valve 38 Open inflow siphon formation valve 36 Closed inflow siphon 35
When stopped, the flow of raw water into tank 1 is stopped,
When the water level in the tank 1 drops due to the overflow of filtrate from the overflow conduit 16 and drops to almost the same level as the water level in the filtrate outflow conduit 16, the siphon breaker valve 20 and the closed air valve 22 are activated.
......--...---Open, supply air from the air supply pipe 23 into the backflow siphon formation tube 21, and use the air pressure P1 to open the backflow siphon formation tube 2.
1 is lowered by Hsm below the water level of the filtered water outflow conduit 16 below the holes, slits, etc. of the communication pipe 18 (P
.

= H, m water column).

(3) Lowering of the water level in the drainage culvert 3 (see Figure 4) Drainage siphon formation valve 10 --- Open drainage siphon breaking valve 12 Closed drainage siphon 9
When it is activated and the water in the drainage culvert 3 is transferred to the drainage outflow culvert 8 by the drainage siphon 9, the water level in the drainage culvert 3 falls to the same level klZ as the upper end of the overflow wall 7 of the drainage outflow culvert 8, and the water is filtered. The water level in the chamber 5 reaches the upper end of the backwash drain trough 6. At this time, the air pressure P supplied from the air supply pipe 23 is P,=H.

m water column.

+41tWater disposal from the filtration chamber 5 (see Figure 5) As mentioned above, when the water level in the filtration chamber 5 reaches the upper end of the backwash drainage gutter 6, the water disposal siphon break valve 14--...- When closed, the vacuum inside the waste water siphon forming pipe 13 becomes the same as the vacuum inside the waste water siphon 9, and the water below the backwash drain gutter 6 passes through the waste water siphon forming pipe 13 to the waste water siphon 9. The water flows out and is discarded into the drain culvert 3, and the water level in the filtration chamber 5 stops at a constant level between the backwash drain trough 6 and the filter layer 4 (see FIG. 6).

(5) Cleaning of filter medium layer 4 (see Figure 6) Discharge siphon destruction valve 14 Opening and discharging siphon forming pipe 13 - Stop and drain siphon forming valve 10
Closed drain siphon destruction valve 12 ・・・Open drain siphon 9 −・−・・−・−Stop air valve 25 −・・−・−−1−−−−・ −−−−
111... When the cleaning air is opened and the cleaning air is forced into the water collection chamber 17 of the filtration chamber from the cleaning air introduction pipe 24, this air rises inside the filter medium layer 4 and fluidly agitates the filter medium layer 4. Furnace materials are cleaned.

During this air cleaning, the water surface expands due to the pressurized cleaning air, but since the water surface is sufficiently lowered from the backwash drain trough 6, the expanded water surface does not reach the upper end of the backwash drain trough 6 and is in a fluid state. The wood will not flow out into the backwash drainage gutter 6.

After performing such air cleaning for a certain period of time, the air valve 25
...---------- Close the siphon, adjust the openings of the siphon breaker valve 20 and the air valve 22, set the air pressure in the backflow siphon forming pipe 21 to P, = H, m water column, and then The water flowing from the forming pipe 21 into the drainage conduit 16 flows back into the water collection chamber 17, rises through the drainage chamber 5, and is backwashed with the turbidity separated from the furnace material by the air cleaning. It reaches the inside of the discharge culvert 3 via the drainage gutter 6.

The cleaning wastewater that has reached the drain culvert 3 is drained into the drain siphon 9.
The wastewater is transferred to the wastewater outflow culvert 8 by restarting the system.

Thus, after the cleaning of the filter medium layer 4 is completed, the above-mentioned filtering is restarted again.

In the above embodiment, cleaning of the filter medium layer 4 using air alone was described, but when cleaning is performed using air and water in combination, the amount of water is controlled so that the water does not reach the backwash drainage gutter 6.

〔Effect of the invention〕

As described above, according to the present invention, a waste water siphon is automatically formed by utilizing the drop in water level in the tank without requiring any complicated control device or special operation, and the water is reversed before air cleaning. It lowers the water level to a predetermined level that is sufficiently lower than the washing drainage gutter, and when cleaning using air or a combination of air and water, it can reliably prevent material from flowing out due to the flow of material, and the structure is extremely simple. This makes maintenance and management easier.

[Brief explanation of drawings]

The drawings are cross-sectional views showing embodiments of the present invention, and are shown in FIGS. 1 to 6.
The figures up to the figure show the order of operations. l...tank, 2...vertical partition wall, 3...drainage culvert, 4
... filter medium layer, 5 ... is a filter chamber, 6 ... backwash drainage gutter,
7... Overflow wall, 8... Drainage outflow channel, 9... Drainage siphon, 10... Drainage siphon formation valve, 11.
...Drainage siphon forming pipe, 12...Drainage siphon destruction valve, 13...Wastewater siphon formation pipe, 14...
・Water siphon destruction valve, 15...Overflow wall, 16...
・Is an overflow drain, 17...Water collection chamber, 18...Communication pipe, 19...Cylinder body, 20...Siphon breaker valve,
21... Backflow siphon forming pipe, 22... Air valve,
23...Air supply pipe, 24...Cleaning air introduction pipe,
25... Air valve, 30... Raw water law docking, 31...
Vertical bulkhead, 32... Inflow section, 33... Outflow section, 34
...Overflow wall, 35...Inflow siphon, 36...
Inflow siphon formation valve, 37... Inflow siphon formation pipe, 38... Inflow siphon destruction valve. Figure 2 Figure 6

Claims (1)

[Claims] (1) Inside the tank (1), a drainage ditch (3
) and a filtration chamber (5) in which a filter medium layer (4) is formed,
A backwash drain gutter (6) is provided in the filtration chamber (5), this backwash drain gutter (6) is communicated with the drain drain (3), and a waste water outflow drain (8) is provided outside the tank (1). Drainage culvert (8) and drainage culvert (3)
are connected to each other through a drainage siphon (9) that enables siphon formation and destruction, and furthermore, one end is opened between the backwash drainage gutter (6) and the filter layer (4), and the other end is connected to the drainage siphon (9). ) A filtration device characterized in that a drain siphon forming pipe (13) is provided which opens at a position above the high water level in the tank (1) and is equipped with a drain siphon breaking valve (14).