JPS62204809A - Back washing device for jet pump and back washing method thereof - Google Patents

Abstract

PURPOSE:To efficiently back-wash the insides of a lifting pipe and a receiving pipe by providing the receiving pipe which is faced to an objective to be pumped up and opened, a jet nozzle provided in the receiving pipe, the lifting pipe and two backwash pipes capable of injecting backwash water. CONSTITUTION:Sand 2 is passed together with water through the insides of a receiving pipe 9 and a sand-lifting pipe 10 and sent to a lifted sand separator 37 by means of the injection of a jet nozzle 16 provided in the receiving pipe 9. On the other hand, in such a case that the receiving pipe 9 and the sand- lifting pipe 10 are clogged by impurities, a backwash valve 46 is opened and a driving water pump 33 is operated and the part near to the aperture end of the receiving pipe 9 is back-washed by both jet water 55 fed from the nozzle 16 and backwash water 57 fed from a first backwash pipe 11. Thereafter the backwash valve 46 is closed and a backwash main valve 48 is opened and the insides of the sand-lifting pipe 10 and the receiving pipe 9 are back-washed by backwash water 58 fed from a second backwash pipe 47 and the backwash water is discharged to a sand basin 1 through the aperture end of the receiving pipe 9.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a jet pump backwashing device and its backwashing method.

BACKGROUND OF THE INVENTION A jet pump can be used to lift objects to be pumped up, such as sand settled at the bottom of a settling basin or sludge in a pit. Conventional jet pumps, for example, as shown in Utility Application No. 152620/1980, have a receiving pipe that opens facing the object to be pumped up, such as sand or sludge, and a receiving pipe that pumps up by injecting jet water into this receiving pipe. It is common to have a jet nozzle that sucks the object into the receiving tube.

Problems to be Solved by the Invention However, in the conventional jet pump as described above, contaminants mixed in the object to be pumped up enter the receiving tube together with the object to be pumped up, causing damage to the receiving tube and the receiving tube. This poses a problem in that there is a risk of clogging the inside of the lift pipe to which it is connected.

Therefore, an object of the present invention is to make it possible to reliably prevent such blockage.

Means for Solving the Problems In order to solve the above-mentioned problems, the device of the present invention includes a receiving pipe that opens facing the object to be pumped up, and a jet water jet is injected into the receiving pipe to remove the object to be pumped up. a jet nozzle for sucking water into the pipe; a lift pipe connected to the receiving pipe; and a first backwash pipe connected to the vicinity of the open end of the receiving pipe and capable of spouting first backwash water into the receiving pipe. , a second backwash pipe that is communicated with the lift pipe and capable of spouting second backwash water from the lift pipe toward the receiving pipe.

In addition, the method of the present invention provides a first backwashing tube that is connected to a receiving pipe that has an opening facing the object to be pumped up and is capable of receiving water jetted from a jet nozzle and sucking the object to be pumped up. The first backwash water is ejected from the pipe, and then the water is discharged into the lift pipe connected to the receiver pipe from the second backwash pipe connected to the lift pipe, through the lift pipe and the receiver pipe. The second backwash water is spouted toward the open end of the receiving pipe.

Operation According to the device of the present invention, the first backwash water jetted from the first backwash pipe into the receiving pipe backwashes the foreign matter present in the vicinity of the opening end of the receiving pipe, and removes the foreign matter. is discharged from the open end of the receiver tube. In addition, the second backwash water that is ejected into the lift pipe backwashes foreign matter present in the pipeline from this lift pipe to the receiving pipe, and discharges it from the open end of the socket in the same way as above. . Therefore, the second backwash water prevents the inside of the lift pipe and the receiving pipe from being clogged with foreign matter, and the vicinity of the open end of the receiving pipe, where blockage with foreign matter is particularly likely to occur, is prevented from being blocked by the first backwashing water. Rinsing with water will reliably prevent blockage.

In addition, according to the method of the present invention, the vicinity of the open end of the receiving pipe where blockage is likely to occur is first backwashed with the first backwashing water, and then the lift pipe and the entire receiving pipe are washed with the second backwashing water. Since backwashing is performed well at , efficient backwashing is possible.

Embodiment In FIG. 1, reference numeral 1 denotes a sand settling basin, at the bottom of which a pit 3 is provided for settling sand 2, which is an object to be pumped up. As shown in FIG. 6, a jet pump 4 is provided at a position corresponding to the pit 3 so as to extend from above the water surface of the settling basin 1 into the sand 2.

3 to 6 show the detailed structure of the jet pump 4. FIG. Here, 5 is a relatively large-diameter driving woodwind, and the 6th
As shown in the figure, it is supported by a floor 6 located above the pit 3. 7 is a supporting support. The lower end of the driving water pipe 5 is closed with a closing plate 8, and this closing plate 8 includes:
A receiving tube 9 whose lower end is open is attached facing downward. On the other hand, a sand lifting pipe 10 as a lifting pipe communicating with the receiving pipe 9 is passed through the inside of the driving water pipe 5, and this sand lifting pipe IO is connected to the driving water pipe 5.
The sand passes through the upper end of the sand separator 37 (see FIG. 1), which will be described later. Similarly, a first backwash pipe 11 is passed through the inside of the driving water pipe 5, and this first backwash pipe 11 is connected to the vicinity of the open end 12 of the receiving pipe 9 (more precisely, between the open end 12 and the blockage plate). 8).

A branch pipe 13 is communicated with the lower end of the driving water pipe 5, and a J-shaped connecting pipe 14 is connected to the branch pipe 13 via a closing plate 8. As shown in detail in FIG. 3, a check valve 15 and a jet nozzle i6 are provided at the tip of this connecting pipe 14.
The six-jet nozzle 16 is provided with a constriction section 17 for jet water generation.

It is arranged at a position facing the open end 12 of the receiving tube 9. An air pipe 18 is connected to the jet nozzle 16 on the distal end side of the constricted portion 17 . This air pipe 18, like the sand pumping pipe IO and the first backwash pipe 11, is passed through the inside of the driving water g5. As shown in FIG. 4, the air pipe 18 and the first backwash pipe 11 are attached and supported to the sand pumping pipe 10 by brackets 19 inside the drive water pipe 5. The detailed structure of the stop valve 15 is shown. Here, 20.20 are upper and lower mounting flanges, and a four-digit frame 21 is provided between both the mounting flanges 20.20. Inside the frame 21 is a pair of flap valves 23 and 23 that open and close around the support shaft 22 using bolts.
are provided, and these flap valves 23, 23 can close a tubular member 24 formed on the lower flange 20 by their own weight. The frame 21 includes a flap valve 2
A stopper bolt 25 is attached to the flap valve 23 for adjusting the opening degree of the flap valve 23.

FIG. 9 shows another example of the check valve 15.

In this example, a spherical body 29 is provided in the water passage 28 provided between the upper and lower mounting seats 26 and 27, and the structure is such that the weight of the spherical body 29 closes the opening 30 of the lower mounting seat 270. Reference numeral 31 denotes a stopper that hits the first sphere 29 and prevents the sphere 29 from rising. Further, 32 is a guide for guiding the sphere 29 to the center of the opening 30.

Next, the conduit system will be explained in detail based on FIG. 3
Reference numeral 3 designates a driving water pump, which is communicated with the aforementioned driving water pipe 5 through a driving water supply pipe 36 equipped with a first pressure sensor 34 and a driving water valve 35 . The sand pumping pipe IO extends from the drive water pipe 5 and is guided to the cyclone 38 of the sand pumping separator 37. 39 is a discharge valve, 40 is a discharge valve, and 41 is a second pressure sensor provided near the cyclone 38. The sand lifting separator 37 includes a sand pocket 42 connected to the cyclone 38, a sand transporter 43 and a sand hopper 44 that receive sand from the sand pocket 42, and a drainage pit 45 that receives separated water from the cyclone 38. have.

The first backwash pipe 11 is branched from the drive water supply pipe 36.

A backwash valve 46 is provided. 47 is the second backwash pipe,
Like the backwash pipe 11, it is branched from the driving water supply pipe 36, connected to the sand pumping pipe 10 portion between the discharge valve 39 and the drain valve 40, and has a backwash main valve 48. The air pipe 18 extends from the drive water pipe 5 and is open to the atmosphere.

A stirring water injection nozzle 49 is provided in the pit 3, and a stirring water supply pipe 51 from the stirring water pump 50 is connected to this nozzle 49.
It is connected to the. The stirred water supply pipe 51 includes a third pressure sensor 52 and a stirring valve 53.

Next, with reference to FIG. 2, the operation based on the above configuration will be explained. That is, once the sand 2 has settled and accumulated in the pit 3 of the sand settling basin 1, first, the start switch 54 shown in FIG. 2 is operated to start the drive water pump 33 and the stirring water pump 50. At this time, each valve is 35 degrees 39, 40, 46, 48.
53 are all kept closed.

Both pumps 33.50 are operated on a timer for about 1 minute or less,
The first and third pressure sensors 34.52 determine whether the discharge pressure has reached a set value.

When this discharge pressure reaches the set value, the discharge valve 39, the discharge valve 40 and the stirring valve 53 are opened, and the discharge valve 39 and the discharge valve 4 are opened.
0 is opened, then the driving water valve 35 is opened. Then,
Stirring water is injected from a nozzle 49 in the pit 3, and the sand 2 is stirred by this stirring water and brought to the center of the pit. Further, by opening the drive water valve 35, the drive water from the drive water pump 33 enters the drive water pipe 5 via the drive water supply pipe 36, passes through the first branch pipe 13 and the connecting pipe 14,
The flap valves 23 and 23 in the check valve 15 are pushed open, and the liquid is injected from the jet nozzle 16 into the receiver pipe 9. Then, due to the jet water 55 injected from this nozzle 16, the sand 2 around the receiving tube 9, which had been stirred by the stirring water from the nozzle 49 as described above, is moved together with water to the open end 12.
The sand is sucked into the receiving pipe 9 and flows through the sand pumping pipe 10.

Therefore, after opening each of the valves 39, 40, 53, and 35, the driving water pump 33 is operated on a timer for a certain period of time.

When the receiving pipe 9 and the sand pumping pipe 10 are not blocked with foreign matter, the pressure (P) inside the sand pumping pipe 10 before the cyclone 38 becomes a value larger than the set pressure (P, ), and this It is detected by the second pressure sensor 41. The timer operation time required for this pressure detection varies somewhat depending on the type of piping system, but is generally about 20 seconds.

If the pressure is detected as described above, it is determined that the pipe line is not blocked, and therefore the jet pump 4 is operated. This main operation is also performed using a timer. The operating time at this time varies depending on the capacity of the pit 3, but is 5 to 10 minutes.
Usually about 1 minute.

At this time, the sand 2 and water sucked into the receiving pipe 9 by the jet water 55 are sent to the sand separator 37 through the sand pumping pipe IO. Here, the sand 2 separated from the water by the cyclone 38 is transported to the sand hopper 44 via the sand pocket 42 and the sand transport machine 43. On the other hand, the water separated by the cyclone 38 is discharged to the drainage bit 45.

When the jet water 55 is injected from the nozzle 16, air 56 is sucked into the nozzle 16 from the air pipe 18 opened to the atmosphere, and this air 56 is injected into the receiving pipe 9 together with the jet water 55 described above. Ru. By injecting the jet water 55 and the air 56 in an air-mixed state in this way, there are effects such as being able to prevent cavitation from occurring within the receiving pipe 9.

When the main operation by the timer is completed, the driving water valve 35 is closed, and the discharge valve 39 and the discharge valve 40 are closed to complete the work. At the same time, the stirring valve 53 is closed,
The stirring water pump 50 is stopped. In addition, the drive water pump 33
When the jet water 55 stops jetting from the nozzle 16 due to the completion of the operation, the flap valve 23 of the check valve 15 closes under its own weight, thereby preventing sand from entering the connecting pipe 14.

On the other hand, if the receiving pipe 9 or sand pumping pipe 10 is clogged with foreign matter, even if the timer operation is performed after opening the valves 39, 40, 53, 35, sand will remain in these pipes 9, 10. Since it does not flow, the sand pumping pipe 1 is detected by the second pressure sensor 41.
0 internal pressure (P) does not exceed the set pressure (Po).

In this case, first, the backwash valve 46 is opened while the drive water valve 35 remains open, and the drive water pump 33 is operated on a timer. Then, the vicinity of the open end 12 of the receiving pipe 9 is backwashed by the jet water 55 from the nozzle 16 and the first backwash water 57 from the first backwash pipe 11 . This eliminates clogging in the area near the open end 12 where clogging is likely to occur. The timer operation time at this time is preferably about 30 seconds.

When this timer operation is completed, the drive water valve 35 and the backwash valve 46 are first closed, the discharge valve 40 is closed, and the backflow main valve 48 is opened, and the timer operation is performed again. Then,
Water from the drive water pump 33 reaches the sand pumping pipe 10 through the second backwash pipe 47, flows backward through the discharge valve 39, and is pushed toward the receiving pipe 9. As a result, the pushed-in second backwash water 58 backwashes the inside of the sand pumping pipe IO and the inside of the receiving pipe 9. The sand settling basin 1 is discharged from the open end 12 of the receiving pipe 9 along with the clogged foreign matter.
released within.

Appropriately, the timer operation time at this time is about 30 seconds.

As described above, the vicinity of the open end 12 of the clogged raw potato receiver pipe 9 is first backwashed with the first backwash water, and then the sand pumping pipe 10 and the receiver pipe 9 are washed almost the entire length with the second backwash water. Since backwashing is performed using the backwash water 58, efficient backwashing is possible. Second
When the backwashing with the backwash water 58 is completed, the discharge valve 40 is opened, the backwash main valve 48 is closed, and the driving water valve 35 is opened, and the pressure is detected by the second pressure sensor 41 by timer operation. Repeat.

In addition to the above-mentioned pressure sensor 41 as a detection means for detecting the occurrence of blockage, it is also possible to use a structure in which the sand pumping pipe 10 is provided with a flow sensor such as a flow relay.

Further, in the above embodiment, the sand 2 in the bit 3 of the sand settling basin 1 is lifted up.

It can also be applied to jet pumps for lifting sludge etc. stored in bits.

Furthermore, as in the above embodiment, by arranging the sand pumping pipe IO 1, the first backwash pipe 11, and the air pipe 18 in one driving water pipe 5, ■ piping can be efficiently arranged and used ■ piping There is no need to provide a support for each pipe. ■ It is possible to prevent scum from getting entangled with the pipes. ■ It is possible to reduce noise.

Effects of the Invention As described above, according to the present invention, the inside of the receiving pipe and the lift pipe can be backwashed efficiently and reliably using the first and second backwash water, thereby preventing the occurrence of blockages in these pipes. can be prevented.

[Brief explanation of drawings]

FIG. 1 is an overall schematic diagram of an embodiment of the present invention. Figure 2 is a flowchart of the operation, Figure 3 is a detailed diagram of the jet pump, and Figure 4 is the TV-r in Figure 3.
V cross-sectional view, Figure 5 is the ■-■ cross-sectional view in Figure 3, and Figure 6 is
7 is a plan view showing an example of the check valve, FIG. 8 is a front view thereof, and FIG. 9 is a front view showing another example of the check valve. 2...Sand (pump-up target), 9...Receiver pipe, 1
0... Sand lifting pipe (lifting pipe), 11... First backwash pipe, 1
2... Opening end, 16... Jet nozzle, 47...
・Second backwash pipe, 55... Jet water, 57... First backwash water, 58... Second backwash water agent Yoshihiro MorimotoH753Figure 4Figure 7 2σ

Claims (1)

[Scope of Claims] 1. A receiving pipe that opens facing the object to be pumped up, a jet nozzle that injects jet water into the receiving pipe to suck the object to be pumped into the receiving pipe, and is connected to the receiving pipe. a first backwash pipe that is connected to the vicinity of the open end of the receiving pipe and is capable of spouting first backwash water into the receiving pipe; A jet pump backwash device comprising: a second backwash pipe capable of spouting second backwash water toward the receiving pipe. 2. A first pipe connected to the receiving pipe that opens facing the object to be pumped up and capable of receiving water jetted from the jet nozzle and sucking the object to be pumped up.
The first backwash water is ejected from the backwash pipe, and then the first backwash water is injected into the lift pipe connected to the receiver pipe from the second backwash pipe connected to the lift pipe, and the water is discharged into the lift pipe and the receiver pipe. A method for backwashing a jet pump, which comprises jetting out second backwash water toward the open end of the receiving pipe.