JPH038801B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Field of Application> The present invention relates to an automatic filtration device whose purpose is to continuously filter wastewater, for example.

<Prior art> In a conventional filtration device, slurry is sent from a slurry inflow pipe into a strainer in the filtration device main body by a pump, passes through the strainer at an appropriate pressure, becomes a clean filtrate, and is released outside the strainer. The filtrate flows into the filtrate chamber and exits from the filtrate outflow pipe provided in the main body.

Solid sludge gradually accumulates inside the strainer.

<Problems to be Solved by the Invention> In the conventional filtration device as described above, when the solid sludge accumulated in the strainer fills the strainer and becomes impossible to filter, the operation of the machine is stopped and the filtration device is stopped. This requires the extremely labor-intensive work of disassembling the strainer, removing the strainer from the machine, cleaning the strainer manually, reinstalling the strainer in the machine, and restarting the machine, which reduces filtration efficiency. There were other problems.

<Means for Solving the Problems> The present invention has been made to solve the above problems.A small-diameter cylindrical strainer is fixed inside a cylindrical main body, and a strainer is connected between the strainer and the main body. A filtrate chamber is provided in the main body, a slurry inflow pipe is connected to the lower end of the strainer, a filtrate outflow pipe is connected to the upper part of the main body, a backwash cylinder is provided in the middle of this filtrate outflow pipe, and a backwash cylinder is provided in the middle of the filtrate outflow pipe. is provided with a backwash piston driven by a cylinder or the like, a filtrate tank is provided at the tip of the filtrate outflow pipe, a cleaning piston that is raised and lowered by a cylinder or the like is provided at the lower end of the strainer, and a cleaning piston is provided at the upper end of the strainer. The apparatus is equipped with a lid that can be opened and closed, and a sludge cleaning device that cleans the sludge on the piston when the lid is opened and the cleaning piston is raised.

<Operation> The present invention has the above structure, and the slurry flowing into the strainer from the slurry inflow pipe passes through the strainer at an appropriate pressure, and the filtrate passes through the filtrate chamber between the strainer and the main body, and then flows into the filtrate outflow pipe. The water flows, filling the backwash cylinder along the way, and then exits through the filtrate tank and out to the discharge pipe.

When it is time for backflow, the filtrate outflow pipe is closed, the backwash piston inside the backwash cylinder rises, and the filtrate in the cylinder is forced into the main body as backwash water to perform backwashing and backflow into the strainer. The backwash liquid is discharged through a bypass valve in a return pipe branched from the slurry inflow pipe.

When it is time to clean the inside of the strainer, the lid on the strainer opens, the cleaning piston rises, and then the sludge cleaning device operates to remove the sludge on the raised piston.

<Example> In Fig. 1, 1 is the main body of the filter, which is cylindrical, and a strainer 2, which is also cylindrical and has numerous small holes, is fixed concentrically inside the main body of the filter, and the outside of this strainer 2 and the main body are fixed concentrically. A filtrate chamber 5 is located between the insides of the chambers 1 and 1. A cleaning piston 4 is installed in the lid 3 at the bottom of the main body 1, and a hydraulic cylinder 6 for operating the piston 4 is provided at the bottom of the main body 1.

A cylindrical body 7 is provided at the upper end of the main body 1, and the upper end of the cylindrical body 7 has an opening, and a lid 8 that can be raised and lowered to open and close this opening, and a hydraulic cylinder 9 that raises and lowers the lid 8 are provided.

Reference numeral 10 denotes a slurry inflow pipe connected to the lid 3, with a pump 11 provided in the middle thereof, a switching valve 12 provided between the pump 11 and the lid 3, and a hydraulic cylinder 13 for operating this switching valve 12.

A return pipe 14 is branched and provided between the switching valve 12 and the lid 3, a bypass valve 15 is provided on the return pipe 14, and the switching valve 12 is further connected to the middle of the return pipe 14 by a bypass pipe 16.

A vertical detection tube 17 is connected to the lid 3, and a magnetically actuated float switch 18 is provided in the middle of the tube.

A filtrate outflow pipe 20 is connected to the upper part of the main body 1,
The upper part of the backwash cylinder 21 is connected in the middle. A backwash piston 22 is installed in the backwash cylinder 21, and a hydraulic cylinder 23 for raising and lowering the piston 22 is provided at the bottom.

A lower part of a filtrate tank 24 is connected to the tip of the outflow pipe 20, and a filtrate discharge pipe 25 is connected to the upper part of this tank 24. Then, the backflow cylinder 21 and the tank 2
A discharge valve 26 is provided between 4 and 4.

An arm 28 that is rotated by a motor 27 is provided on the upper side of the cylindrical body 7, and sludge removing blades 29 are provided at the lower portions of both ends of the arm 28 to constitute a sludge removing device 30.

In addition, 31 in FIG. 1 is a pressure switch that detects the pressure inside the cylinder 7, and is used to detect an abnormal increase in the pressure inside the strainer 2 and issue an alarm.

In addition, 32 in the figure is an air layer, and this air layer 32
The liquid in the strainer is discharged to the return pipe 14 and the bypass valve 15 by the pressure of the air layer when the internal pressure becomes zero.

Furthermore, when the piston 4 rises, it exposes its head to the air layer 32, which has the effect of separating gas and liquid.

Next, the operation of the above embodiment will be explained. pump 1
The slurry sucked in from the inflow pipe 10 during operation 1 passes through the switching valve 12 and is transferred from the lid 3 to the strainer 2.
Go inside.

The return pipe 14 connected to the inflow pipe 10 has a bypass valve 15, and the switching valve 12 is in the position shown in FIG. The pressure required when passing through the strainer 2 is adjusted.

The slurry that has entered strainer 2 is pumped to pump 1.
The liquid passes through the strainer 2 at a pressure of 1 and comes out as a filtrate into the filtration chamber 5 in the main body 1 outside the strainer 2.

This filtrate once fills the backwash cylinder 21 (first time only), enters the filtrate tank 24 through the discharge valve 26, and exits from the discharge pipe 25.

Then, when the strainer 2 becomes clogged over time, a backwash signal is issued at a time set in advance by a timer, and the backwash process begins.

In this backflow process, when the signal from the timer is input as described above, the switching valve 12 changes to the state shown in FIG. .

Under this condition, the cylinder 23 works, the backwash piston 22 rises, and the filtrate filling the backwash cylinder 21 is sent into the main body 1 as a backwash liquid.

This liquid enters the inside of the strainer 2 from the filtrate chamber 5 outside the strainer 2 due to the pressure exerted by the piston 22, and the strainer 2 is backwashed.

The liquid contaminated by backwashing the strainer 2 is discharged from the return pipe 14 via the bypass valve 15, which is always open.

When the backwash is finished, the discharge valve 26 opens and the backwash piston 22 moves down, but at this time, the filtrate tank 2
The filtrate from No. 4 returns to the backwash cylinder 21, and this backwash cylinder 2
1, so as long as there is filtrate in the filtrate tank 24, continuous backflow is possible.

Further, since the filtrate chamber 5 between the main body 1 and the strainer 2 is always filled with filtrate, even a small amount of liquid in the backwash cylinder 21 can sufficiently exert the backwash effect.

However, if the diameter of the backwash cylinder 23 is made large, a very large backwash pressure can be obtained since the diameter of the backwash cylinder 21 is small, so even if the strainer 2 is thick, sufficient backwashing can be performed.

Operate continuously while repeating backwashing as described above. If continuous operation is continued in this manner, sludge will adhere to the bottom of the strainer 2 and the inner surface of the strainer 2.

The time until this happens is set in advance by a timer, and when that time comes, the cleaning process begins.

In this cleaning process, when a signal from the timer is input, the discharge valve 26 remains open and the switching valve 12 is switched to the state shown in FIG. 2b, and the slurry no longer enters the strainer 2.

At this time, there is still pressure inside the strainer 2 and the bypass valve 15 is open, so the liquid in the strainer 2 is quickly discharged from the return pipe 14. When the liquid in the strainer 2 is discharged in this way, the float 19 that activates the float switch 18 of the detection tube 17 comes down, the float switch 18 is turned on, and the cleaning process begins. During this cleaning process, the float switch 18
When turned ON, the cylinder 6 works and the cleaning piston 4 rises, but at this time, the sludge that has settled on the top surface of the piston 4 and the strainer 2
The piston 4 rises while cleaning the sludge adhering to the inner surface of the piston 4.

Furthermore, when the piston 4 starts to rise, the upper cylinder 9 also works to raise the lid 8 and release the upper end of the cylinder 7 as shown in Figure 4, so the piston 4 carrying the sludge is released. The head is exposed at the upper end of the cylindrical body 7, and the upper surface of the piston 4 and the upper end of the cylindrical body 7 are made to be on the same plane.

Next, the motor 27 is activated, the arm 28 rotates, and the sludge removal vane 29 drops the sludge on the piston 4 onto the receiving plate 32 (FIG. 3) on the side of the cylinder 7. Thereafter, the piston 4 is lowered to its original position, and the lid is also lowered to close the upper end of the cylinder 7.

The device then returns to the initial operating state and resumes operation.

As mentioned above, if the strainer 2 becomes clogged for some reason and the pressure inside the strainer 2 rises abnormally before the strainer 2 is backwashed or cleaned by the timer signal, the pressure switch 31 is activated. When activated, an alarm is issued, and a backwashing or cleaning process can be performed using a manually operated switch or the like.

<Effects> As described above, the present invention provides a backwash cylinder and a filtrate tank in the filtrate outflow pipe connected to the filtration device main body, and stores filtrate in both, thereby preventing slurry from flowing into the strainer during backwashing. stop and
Backwashing can be automatically performed in a very short time simply by raising the piston in the backwash cylinder.

Furthermore, when the strainer needs to be cleaned, the strainer can be cleaned automatically by opening the lid at the upper end of the strainer and lifting the cleaning piston inside the strainer.

Moreover, since the sludge on the raised cleaning piston that has cleaned the inside of the strainer is automatically removed by the sludge removal device, the entire filtration process is automated.

Therefore, filtration can be carried out continuously without requiring any manual labor.

Further, if a bypass valve is provided between the switching valve of the slurry inlet pipe and the strainer as in the embodiment, it becomes unnecessary to stop the pump each time during the backwashing or cleaning process, and there is no need for a separate circuit or valve. Furthermore, if a cylindrical body is provided on the strainer of the main body as in the example, when the operation is resumed after backwashing or cleaning, the liquid flowing into the main body pushes up the air inside the main body and compresses it. remains inside the cylinder and balances with the liquid pressure passing through the strainer, so no air remains inside the strainer, which has the effect of eliminating the need for an air venting process at all.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional front view of the main parts showing one embodiment of the fully automatic filtration device of the present invention, Fig. 2 a and b are enlarged sectional views showing each state of the switching valve, and Fig. 3 is a sludge removal device. The plan view and FIG. 4 are partially cut away sectional views showing the operation of the sludge removing device. DESCRIPTION OF SYMBOLS 1... Main body, 2... Strainer, 4... Cleaning piston, 7... Cylindrical body, 8... Lid, 10... Slurry inflow pipe, 11... Pump, 12... Switching valve, 14... Return pipe, 15... Bypass valve, 18... Float switch, 20... Filtrate outflow pipe, 21... Backwash tube, 22... Backwash piston, 24... Filtrate tank, 25... Filtrate discharge pipe, 26... Discharge valve, 30... Sludge removal device, 3
2...Air layer.

Claims (1)

[Claims] 1 A small-diameter cylindrical strainer is fixed in a cylindrical body, a filtrate chamber is formed between the strainer and the body, a slurry inflow pipe is connected to the lower end of the strainer, and an air layer is provided above the body. A filtrate outflow pipe is connected to the filtrate outflow pipe, a backwash cylinder is provided in the middle of the filtrate outflow pipe, and a backwash piston driven by a cylinder or the like is provided in the backwash cylinder,
A filtrate tank is provided at the tip of the filtrate outflow pipe, and a cleaning piston that is raised and lowered by a cylinder or the like is provided at the lower end of the strainer, and a lid that can be opened and closed is provided at the upper end of the strainer. A fully automatic filtration device characterized by being provided with a sludge removal device that removes sludge on a cleaning piston under the condition that the cleaning piston is raised.