JPH0137191B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an excess filter protection device.

Excess filters include tubular type, spiral type, flat plate type, hollow fiber type, etc. In recent years, one example is the hollow fiber type, which has a small installation area and can be used at low pressure, and is particularly advantageous for pure water production equipment. This will be explained using an excess filter as an example.

As shown in Fig. 1, the hollow fiber type excess module has a hollow fiber bundle 1 assembled into a cartridge 2, in which introduced water 3 introduced into the inside is converted into permeated water 4 flowing out through the surroundings of the fibers. It has a structure in which it separates into water and rejected water 5 which flows out to the outside along the central axis, and is used as a means for fractionating, concentrating, and purifying macromolecules in solutions and colloids in suspension. It is something.

To explain the movement of water within the hollow fibers constituting the hollow fiber type excess module, as shown in FIG. It is separated into permeated water 8 which passes through and flows out, and rejected water 9 which flows out from the other through the hollow part. The one shown here is an internal pressure type that introduces the introduced water 7 into the inside of the hollow fiber 6, but there is also an external pressure type that leads the introduced water 7 to the outside.

FIG. 3 shows a conventional example of an ultrapure water production system incorporating this excess filter. In FIG. 3, 10 indicates an excess unit using one or more excess modules, 10A indicates an excess membrane,
10B indicates the introduced water and excluded water side, and 10C indicates the permeated water side. This system includes a pressurizing pump 14 connected to an input line 11 from a storage tank 18 to an excess unit.
water is sent to the excess unit 10 by providing
The permeated water that has passed through the excess unit 10 passes through the permeated water pipe 12 and is used in a required amount at a use point 24 by operating a valve 23 on the way, and the remaining water is piped back to the storage tank 18 and sent to the input pipe 11. The flow meter 15 provided at
The opening degree of the regulating valve 17 is adjusted so that the opening degree becomes 1.

A liquid level gauge 19 is installed in the storage tank 18, and a solenoid valve 20 provided in the raw water supply pipe 21 is operated to maintain a predetermined liquid level. Note that 22 indicates a signal line from the liquid level gauge.

By the way, in the above system, regardless of the amount of water used at the point of use, the amount of water passing through the excess filter 10 and the amount of rejected water are almost constant, so a large amount of water is wasted as rejected water, and the excess filter 10 No. 10 is always operated with a large amount of water, which causes clogging in a short period of time and causes wear and tear.

The present invention solves the above problems all at once. In the present invention, a rejected water pipe is connected to the rejected water side of an excess filter having a structure that separates introduced water into permeated water and rejected water, and a water supply port to each use point is connected to the permeated water side, and the filter is connected to the rejected water side. A flow rate detection device for detecting the flow rate of flowing water is provided in the input pipe and the rejected water pipe or the permeated water pipe, respectively, and a solenoid valve is interposed in the rejected water pipe, and a solenoid valve is provided in the rejected water pipe to receive signals from both flow rate detection devices and detect the flow rate. Equipped with a flow rate control device that controls the opening of the solenoid valve to keep the flow rate in the rejected water pipe constant relative to the flow rate in the input pipe, and adjusts the amount of rejected water according to the amount of water used at the point of use. As a result, wear and tear on excess filters can be significantly reduced, and furthermore, a large amount of rejected water, which was previously wasted, can be saved.

The present invention will be explained below with reference to the drawings. FIG. 4 shows a system for removing particles from pure water using the above-mentioned excess filter. In the same drawing, 2
5 is the excess unit, 25A is the excess membrane, 25
B is the inlet water and rejected water side of the unit, 25C
indicates the permeate side. Permeated water side 25 of unit 25
One or more use points 41 and faucets 40 are connected to the permeated water pipe 27 connected to C. Furthermore, flow rate indicating controllers 29 and 30 are installed in each of the input pipe 26 and the rejection water pipe 28 of the unit 25 to detect the flow rate in the pipes, and a solenoid valve 31 is installed in the rejection water pipe 28. A flow control device is connected to the electromagnetic valve 31, which receives signals from the flow rate indicating controllers 29 and 30 and adjusts the opening degree thereof.

In this embodiment, the flow rate control device is the ratio setting meter 3.
2. Consisting of a cascade type indicating controller 33 and a solenoid valve controller 34, the signal from the flow rate indicating controller 29 connected to the input pipe 26 enters the input of the ratio setting meter 32 via the signal line 35, The output of 32 is connected via signal line 36 and to the reject water line 28.
A signal from the flow rate indicating controller 30 connected to the cascade type indicating controller 33 is inputted as a setting input and a measurement input via a signal line 37, respectively.

The signal of the cascade type indicating controller 33 is the signal line 3
8 to the solenoid valve controller 34,
Its output regulates the solenoid valve 31 via a signal line 39.

In the preferred embodiment, the pressurized inlet water enters the excess unit 25 from the input line 26, the separated permeate is used at the point of use 41, and the reject water is discharged. Depending on the usage amount at the use point 41, the flow rate indicating controllers 29 and 30 send a signal to the flow control device, and the opening degree of the solenoid valve 31 is adjusted to adjust the flow rate of the reject water pipe 28 to the flow rate of the input pipe 26. Fix it to, for example, 10% of the flow rate. This limits the amount of water introduced and suppresses wasteful removal of water.

In addition to detecting the flow rate of introduced water, the flow rate may be detected in the permeated water pipe 27 immediately after the excess filter 25.

According to the present invention, the flow rate of rejected water is controlled according to the amount of water used at the point of use, and
Since the amount of introduced water sent into the excess filter 25 is suppressed to the necessary minimum, it is possible to prevent damage to the excess filter 25 without placing an unnecessary burden on it, and to effectively protect the excess filter 25. This has the effect of reducing wasteful water discharge and saving water consumption.

Examples of the present invention will be described below.

Example: The conventional system shown in Figure 3 was used in a laboratory where an excess filter was used as a terminal treatment to remove particles from pure water.The maximum water consumption at the point of use was 900/Hr, and the average water consumption was is 300
/Hr, the experimental time per day was 9 hours, and the permeate amount used per day was 2700. In addition, the flow rate of introduced water was constant at approximately 1500/Hr, and the amount of water removed was 150/Hr, which was 10% of that, and the amount of water removed per day was 1350/Hr. Additionally, excess filters were replaced every year.

The excess filter unit is left intact and replaced with a system equipped with the protection device according to the invention, and the flow indicator controller 29 of the input line 26 is connected to the 100%
/Hr to 1000Hr, and an electromagnetically coupled floating flowmeter for 10/Hr to 100/Hr is used as the flow rate indicating controller 30 on the rejection water pipe 28, and Introducing the water flow rate
The ratio setting meter 32 was set so that the ratio was 10%. Note that the linearity of the flowmeter is 100/100% as shown above.
Since it is only within the range of Hr to 1000/Hr and 10/Hr to 100/Hr, the signal was set so that the flow rate of introduced water and the flow rate of removed water are as shown in Fig. 5. The amount of introduced water and the amount of removed water are 100/Hr to 1000
/Hr range, it is proportional, and the amount of water introduced is 100/Hr.
The amount of water removed when the water is below Hr is constant at 10/Hr.
I made it so that By doing this, it was possible to suppress pressure fluctuations on the membrane surface when the faucet at the point of use was suddenly opened.

As with the conventional system, the average water consumption is 300/Hr at a maximum of 900/Hr, and the amount of permeated water used per day is reduced.
It was operated under the condition of 1500/Hr. The resulting water quality is the same as before, and the amount of water removed per day is
It was kept to 200. Furthermore, although two years have passed since it was put into operation, the module still has initial performance, and the protective function of the present invention has been fully demonstrated.

In addition, the amount of water removed is 200 compared to the conventional 1350 per day.
significantly reduced to.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of the hollow fiber type excess filter module used in the present invention, Figure 2 is an explanatory diagram showing the movement of water within the hollow fiber type excess filter module, and Figure 3 is an explanatory diagram showing the movement of water within the hollow fiber type excess filter module.
Fig. 4 is a flow diagram of an example of a conventional excess system, Fig. 4 is a flow diagram of an excess system equipped with a protection device according to the present invention, and Fig. 5 is a flow diagram of an input pipe flow rate and a rejected water flow rate in an embodiment of the present invention. It is a graph showing a relationship. 1...Hollow fiber bundle of hollow fiber type excess module, 2...Hollow fiber type excess module, 3...
Introduced water, 4... Permeated water, 5... Rejected water, 6... Hollow fiber as excess element, 7... Introduced water, 8...
...Permeated water, 9...Rejected water, 24...Use point, 25...Excess unit, 25A...Excess membrane, 25B...Introduced water and rejected water side of excess unit, 25C...Permeated water side of excess unit , 26...Input pipe line, 27...Permeated water pipe line, 2
8... Exclusion water pipe, 29, 30... Flow rate indicating controller, 31... Solenoid valve, 32... Ratio setting meter, 33
...Cascade type indicating controller, 34...Electric valve controller, 35, 36, 37, 38, 39...
Signal line, 40... Faucet, 41... Point of use.

Claims (1)

[Claims] 1 Connect the rejected water pipe to the rejected water side of the excess filter, which has a structure that separates the introduced water into permeated water and rejected water, and connect the water supply ports to each use point to the permeated water side, and input to the filter. A flow rate detection device for detecting the flow rate of flowing water is provided in each of the pipe and the rejected water pipe or the permeated water pipe, and a solenoid valve is interposed in the rejected water pipe, and the electromagnetic valve receives signals from both flow rate detection devices. A protection device for an excess filter, characterized in that the device is equipped with a flow rate control device that controls the opening degree of the filter to maintain a constant flow rate in the reject water pipe relative to the flow rate in the input pipe.