JPH0478322B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a device for taking out liquid in a vacuum tank to the outside without releasing the vacuum. For example, in a vacuum filtration device, continuous filtration is not possible. It is possible.

[Conventional technology]

For example, in a vacuum filtration device that introduces filtrate from a filtration belt into a vacuum tank, conventionally, in order to take out the filtrate in the tank, the vacuum in the tank is released and the tank is opened to atmospheric pressure. It had to be extracted outside by applying pressure. Therefore, it was not possible to continue filtration. Therefore, the device had the disadvantage of being large compared to its filtration capacity. Another disadvantage of intermittent filtration is that the cake on the filter material is destroyed when the vacuum is released, resulting in a decrease in filtration accuracy.

[Problem that the invention seeks to solve]

As mentioned above, according to the conventional technology, continuous operation of vacuum filtration equipment is impossible, the equipment is large,
The disadvantage of intermittent filtration is that the filtration accuracy is reduced.

This invention improves the above-mentioned drawbacks, and allows continuous filtration to be performed while continuously maintaining a vacuum state without releasing the vacuum, and also allows liquid in a tank in a vacuum state to be taken out to the outside. This will greatly improve the filtration capacity, eliminate cake destruction caused by conventional intermittent vacuum suction, improve filtration accuracy and save on filtration material, and provide a compact, high-capacity, high-precision filtration device. The purpose is to

[Means to solve the problem]

The device for taking out liquid in a tank in a vacuum state according to the present invention has the following configuration as a means for achieving the above object.

A small tank 1 having an inlet for receiving filtered liquid at the top and connected to a discharge pipe having check valves 2, 3, and 4 arranged in series at the bottom, an upper tongue 8 and a lower tank 7 arranged above and below. The upper tank 8 is connected to the branch port 5 between the check valves 2 and 3 via the branch port 10, and the lower tank 7 is connected to the branch port 10 via the internal check valve 11, and also directly A solenoid valve 17 is connected to the branch port 6 between the check valves 3 and 4, and a solenoid valve 17 is connected to the connecting pipe at the top of each of the upper tank 8 and the lower tank 7.
A pressure source is connected between the solenoid valve 17 of the connecting pipe and the lower tank 7 via an electrode valve 16, and at least the upper tank 8 is provided with a vacuum pump or a solenoid valve 15. An air ejector 13 is provided, and level switches 1 are provided at the upper and lower portions of the lower tank 7.
The solenoid valves 15, 16, 1 are activated by the signals of 8, 19.
7 or operate the drive switch of the vacuum pump to take out the liquid to the outside via the check valve 4 at the appropriate time.

The upper tank 8 and the lower tank 7 are provided with air ejectors 13 and 12 having vacuum pumps or solenoid valves 15 and 14, respectively.
The solenoid valves 14, 15,
The liquid was taken out to the outside through the check valve 4 at appropriate times by opening and closing the valves 16 and 17 or by operating the drive switch of the vacuum pump.

[Effect]

This invention has a small tank 1 that is in contact with the lower part of the sewage tank via a filter belt, and an upper tank 8 and a lower tank 7 that are connected via a solenoid valve 17, and these tanks are connected to each other by a check valve. Since a vacuum pump or an air ejector is connected to at least the upper tank 8, the solenoid valve can be opened and closed by signals from level switches 18 and 19 installed in the lower tank 7. , or operate the vacuum pump drive switch to automatically open the upper tank 8.
Then, the lower tank 7 is evacuated and compressed air is introduced into the lower tank 7, and the filtrate in the small tank 1 can be taken out directly or continuously through the lower tank 7.

〔Example〕

An embodiment of the present invention will be described using a vacuum filtration device as an example with reference to the drawings.

In Fig. 1, numeral 1 is a small tank, and the ceiling surface at the upper center of the tank is a mesh-like punch board, and the upper part of the tank is formed so that sewage is supplied to the upper part through a filter belt. . In addition, a hole with a diameter according to the flow rate is provided on the bottom of 1, and a check valve is installed in 3.
Connect the discharge pipes arranged in series and check valves 2 and 3.
A branching port 5 is provided between the check valves 3 and 4, and a branching port 6 for connection to the lower tank 7 is also provided between the check valves 3 and 4. The port 5 is connected to the upper tank 8 by piping, and a branching port 10 is provided in the middle of this piping and connected to the lower tank 7 via a check valve 11.

Air ejectors 12 and 13 are attached to the lower tank 7 and upper tank 8, respectively, and dedicated 2-port solenoid valves 14 and 15 are provided for each, and 2-port solenoid valves 16 and 17 for vacuum release are provided respectively.

When the liquid containing sludge continuously flows into the upper surface of the filter belt, if the filter belt is not clogged, the liquid will naturally pass through the filter belt and fall into the small tank 1 due to its own weight. It flows out of the device through the check valves 2, 3, and 4.

When sludge accumulates on the filter belt and becomes clogged and cake-like, the level of the liquid flowing onto the filter belt rises, so the float switch 9 detects the height of the liquid level. Then, open the 2-port solenoid valves 14 and 15 to pass the compressed air to the air ejector (or close the switch for driving the vacuum pump motor instead of the 2-port solenoid valves 14 and 15 to release the respective vacuums). The description in parentheses is the description when a vacuum pump is used instead of the air ejector and solenoid valve, and the same applies hereinafter. ...The generated vacuum pressure evacuates the small tank 1 through piping from the upper tank 8 and the lower tank 7, so the liquid on the filter belt is pushed by the pressure and flows into the tank 1, the lower tank 7, and the upper tank 8. At this time, the 2-port solenoid valve 16 remains closed, the 2-port solenoid valve 17 opens, and the upper tank 8
Since the lower tank 7 is in communication with the lower tank 7, the liquid mainly flows through the lower tank 7 through 10 and 11 due to the head difference.
flows towards. When the lower tank 7 is filled with liquid, the solenoid valve 17 is activated by the level switch 18.
and 14 (or stop the vacuum pump for the lower tank and close the solenoid valve 17 at the same time) solenoid valve 16
is opened, compressed air is introduced into the lower tank, and the liquid inside is pushed out to the outside. At this time, the check valve 3 is closed, and the liquid is forced open the check valve 4 and is discharged in a short time.

Since the upper tank 8 remains evacuated during the operation, the liquid from the tank 1 does not flow into the lower tank 7 but into the upper tank 8.

When the liquid accumulated in the lower tank 7 is drained, the solenoid valve 16 is turned off by the level switch 19.
close and open solenoid valves 17 and 14 (or open solenoid valve 17 to drive the vacuum pump in the lower tank)
Therefore, the lower tank becomes vacuum again, the check valve 4 is closed, the check valve 3 is opened, and the liquid flows into the lower tank 7. At this time, since the solenoid valve 17 is open, the liquid accumulated in the upper tank 8 is transferred to the piping port 1 due to the head difference.
0 and flows into the lower tank 7 through the check valve 11. Therefore, at this time, the tank 1 is in the lower tank 7.
Then, liquid flows in from both upper tanks 8, and when the lower tank 7 is filled with liquid again, the above operation is repeated again and the liquid is discharged out of the apparatus.

The above operations are repeated until the filter belt is completely clogged and filtration is no longer possible.

The above-described device can also be used without the solenoid valve 14 and air ejector 12 if it processes a small flow rate.

That is, the solenoid valve 1 is activated by the flow switch 9.
When valve 5 is opened and the upper tank 8 is evacuated, solenoid valve 1
Since 6 is closed and 17 is open, the lower tank 7 also becomes a vacuum, and liquid flows into the lower tank 7 due to the head difference. When the liquid level rises and the level switch 18 operates to open the solenoid valve 16 and close the solenoid valve 17, the liquid in the lower tank 7 is pushed out by compressed air and the check valve 4
is discharged from. When the liquid level falls and the level switch 19 is activated, the solenoid valve 16 closes and the solenoid valve 17 opens, so that the lower tank 7 receives the vacuum from the upper tank 8 and becomes vacuum, and the check valve 4 closes and the check valve 3 opens and the liquid The liquid flows into the lower tank 7, and by repeating the above operations, the liquid in the small tank in a vacuum state can be continuously taken out.

〔Effect of the invention〕

Volume of lower tank 7: 65, volume of upper tank 8:
50, and using a timer instead of level switches 18 and 19 on the lower tank, the flow rate is 100.
/min, the filtration throughput was approximately twice that of the conventional device, the filter belt usage time was increased by 120%, saving on filter media, and the filtration accuracy was improved.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention. 1...Small tank, 2...Check valve, 3...Check valve, 4...Check valve, 5...Branch port, 6...Branch port, 7...Lower tank, 8...Upper tank , 9...Float switch, 10...Branch port, 11...Check valve, 12...Air ejector,
13... Air ejector, 14... 2 port solenoid valve, 15... 2 port solenoid valve, 16... 2 port solenoid valve, 17... 2 port solenoid valve, 18... Level switch, 19... Level switch.

Claims (1)

[Scope of Claims] 1. A small tank 1 having an inlet for receiving filtered liquid in the upper part and connected to a discharge pipe having check valves 2, 3, and 4 arranged in series in the lower part, and a small tank 1 arranged above and below. It consists of an upper tank 8 and a lower tank 7, and the upper tank 8 is connected to the check valves 2 and 3 via a branch port 10.
The lower tank 7 is connected to the branch port 5 between the check valves 3 and 4 through an internal check valve 11, and directly connected to the branch port 6 between the check valves 3 and 4. A solenoid valve 17 is provided in each upper connecting pipe of the lower tank 7, and an electrode valve 1 is provided between the solenoid valve 17 of the connecting pipe and the lower tank 7.
A pressure source is connected via 6, and at least a vacuum pump or solenoid valve 15 is connected to the upper tank 8.
An air ejector 13 having a
The solenoid valve 1 is activated by signals from level switches 18 and 19 placed at the upper and lower parts of the lower tank 7.
5, 16, 17 or by operating a drive switch of a vacuum pump to take out liquid from a tank in a vacuum state at a timely manner through a check valve 4. Device. 2. The upper tank 8 and the lower tank 7 are provided with air ejectors 13 and 12 having vacuum pumps or solenoid valves 15 and 14, respectively, and level switches 18 and 12 are provided at the upper and lower parts of the lower tank 7, respectively.
19, the solenoid valves 14, 15, 16, 1
7 or by operating a drive switch of the vacuum pump to take out the liquid to the outside via the check valve 4 at a suitable time. A device that extracts liquid from a tank.