JP3132044B2 - Liquid supply device for membrane separation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid supply device for a membrane separation device, and more particularly to a liquid supply device for a membrane separation device suitable for use in a secondary or advanced treatment system for biological treatment. .

[0002]

2. Description of the Related Art As is well known, a membrane separation apparatus pressurizes and supplies a liquid to one side of a separation membrane and takes out permeated water from the other side. If the SS component in the liquid (raw water) such as sludge is large, blockage of the separation membrane and its raw water flow path (hereinafter, blockage of the separation membrane) is likely to occur.

[0003]

In particular, in the case of the tubular type membrane separation apparatus, when the separation membrane is clogged, it is not possible to take measures such as frame cleaning, and the replacement of the entire separation membrane is inevitable. Further, it is expected that blockage of the separation membrane can be prevented even in a membrane separation device such as a flat plate type and a hollow fiber type other than the tubular type.

[0004]

According to the present invention, there is provided a liquid supply device for a membrane separation device, which comprises a pump for supplying biological treatment water to the membrane separation device and a viscosity of the biological treatment water supplied to the membrane separation device. A torque meter; and a control device for stopping the pump when a detected value of the torque meter becomes equal to or more than a predetermined value.

[0005]

[Action] The inventors of the present invention we have conducted various research, biological treatment
When the SS concentration in Risui increases viscosity (the detected value of the torque meter) it gradually increases, and, in particular to 2 to 4%, the critical value of the torque meter detection value of the order of 2-4% It was found that when the SS concentration was exceeded, the torque meter detected value rapidly increased. The SS concentration of about 2 to 4% is also an SS concentration that tends to cause blockage in the membrane separation device if it exceeds that, and if the operation is continued, the separation membrane will be blocked.

Therefore, the present invention stops the supply of the liquid to the membrane separation device when the viscosity value detected by the torque meter becomes a predetermined value or more, thereby preventing the separation membrane of the membrane separation device from being blocked. It is like that.

The present invention prevents clogging of a separation membrane when using a membrane separation device for biological treatment of wastewater.

In particular, the viscosity of the biologically treated water to be supplied to the membrane separation device is measured, and when the measured value exceeds a set value, the pump is stopped to stop the operation of the membrane, and the cleaning is started.

[0009] In biological treatment, the membrane separation device is a secondary treatment system containing a large amount of activated sludge and an advanced treatment system comprising coagulated sludge.
It is used in a system containing a large amount of S, and may be measured by providing a torque meter in both systems. Particularly, the system is preferably used in this system because the clogging is severe in an advanced treatment system.

[0010] When the membrane separation device is operated, the concentration of SS is increased due to high concentration due to fluctuations in the amount of raw water and water quality, fluctuations in FLUX, and the like. In the present invention, a part of the biologically treated water in the raw water tank is extracted, the torque value is intermittently measured, and 3% or more is measured.
Stop the circulating pump and move to washing. Since the amount of liquid in the raw water tank increases during washing and the membrane concentrated liquid is not returned, the concentration in the raw water tank becomes a predetermined value.

[0011]

FIG. 1 is a system diagram of a water treatment apparatus incorporating a liquid supply device of a membrane separation apparatus according to an embodiment.

[0012] Biological treatment of the secondary processing the raw water suitable aggregating agent is added to the water is stored in the raw water tank.

The raw water in the raw water tank 1 is supplied to a tubular type membrane separation device 4 via a liquid supply pump 2 and a pipe 3. The permeated water is taken out of the system by a pipe 11, and the concentrated water is returned to the raw water tank 1 by a pipe 5. From the pipe 2, a pipe 6 for introducing a part of the liquid supply to the torque meter 7 is branched.

The liquid whose viscosity is measured by the torque meter 7 is supplied to a pipe 8
Is returned to the raw water tank 1. The detected value of the torque meter 7 is converted by the converter 9
Is input to the control device 10 through The control device 10 outputs a control signal to the liquid supply pump 2.

FIG. 2 is a correlation diagram between the SS concentration in the raw water and the torque meter detected value. As shown, when the SS concentration exceeds 3%, the torque meter detected value sharply increases. In the present embodiment, a value (-4 V) corresponding to this sharp rising portion of the torque meter detection value is set as a threshold, and when the torque meter detection value exceeds this threshold, the liquid supply pump 2 is stopped, and the operation shifts to cleaning. I do.

When the liquid is introduced into the torque meter 7 and the measurement is started, the detected value of the torque meter reaches a peak value immediately after the start of the rotation of the torque meter, and thereafter becomes a slightly reduced constant value. . Therefore, the torque meter operates intermittently at regular intervals. In FIG. 2, the peak value immediately after the start of the measurement is adopted as the torque meter detected value.

According to the apparatus of this embodiment, when the SS concentration becomes high enough to cause blockage in the membrane separation device, the liquid supply pump 2 is automatically stopped. Is prevented.

It should be noted that the threshold value employed in the above embodiment is merely an example, and it is needless to say that the threshold value is appropriately selected according to the properties of the raw water.

[0019]

As described above, according to the liquid supply device of the membrane separation device of the present invention, it is possible to prevent the separation membrane of the membrane separation device from being blocked. Therefore, it is possible to operate the membrane separation device stably for a long period of time.

[Brief description of the drawings]

FIG. 1 is a system diagram of a water treatment device provided with a liquid supply device of a membrane separation device according to an embodiment.

FIG. 2 is a graph showing an example of a torque meter detection value.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Raw water tank 2 Feed pump 4 Membrane separation device 7 Torque meter 10 Control device

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshio Shiibashi 3-4-7 Nishi-Shinjuku, Shinjuku-ku, Tokyo Inside Kurita Kogyo Co., Ltd. (56) References JP-A-57-84712 (JP, A) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) B01D 61/00-65/10 C02F 1/44

Claims (1)

(57) [Claims] 1. A pump for supplying biological treatment water to a membrane separation device, a torque meter for measuring the viscosity of biological treatment water supplied to the membrane separation device, and a detection value of the torque meter being equal to or more than a predetermined value. And a control device for stopping the pump in the event of a failure.