JPH06218246A - Flat membrane filter machine - Google Patents

Abstract

PURPOSE:To suppress an excessive load fluctuation of a motor for driving flat membranes and to obviate the generation of a variation in filtrate quality by providing a means for detecting the temp. of the original liquid in the outlet part of a pressure vessel and a means for controlling the rotating speed of the flat membranes in such a manner that the temp. of the original liquid in the outlet part of the pressure vessel does not exceed a prescribed value. CONSTITUTION:The rotary flat membrane filter machine which executes cross flow type filtration of the original liquid by rotating the flat membranes in the pressure vessel 11 is provided with a means 41 for detecting the temp. of the original liquid in the outlet part of the pressure vessel 11 and a means 13 for controlling the rotating speed of the flat membranes in such a manner that the temp. of the original liquid in the outlet part of the pressure vessel 11 does not exceed a prescribed value. Consequently, the flat membrane filter machine which can maintain the temp. of the original liquid in the pressure vessel at an adequate value at all times, can suppress the excessive load fluctuation of the motor 12 for driving the flat membranes according to the temp. control of the original liquid and does not generate the variation in the quality of the filtrate by a difference in the lots of the original liquids is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat membrane filter used in the fields of food production, drug development, fermentation and the like.

[0002]

2. Description of the Related Art A rotary flat membrane filter for performing cross-flow filtration of a stock solution by rotating a flat membrane in a pressure vessel, and a flat membrane fixed in a pressure vessel, and the flat membrane is fixed in the pressure vessel. 2. Description of the Related Art A fixed flat sheet membrane filtration machine that performs cross-flow type filtration of a stock solution by rotating parallel stirring plates has been conventionally known. In the flat sheet membrane filter, heat is generated by friction between the rotating flat sheet membrane or the rotating stirring plate and the stock solution. The calorific value of frictional heat increases as the concentration of the stock solution increases with the progress of the filtration process, and as the viscosity of the stock solution increases, and finally exceeds the capacity of the heat exchanger provided in the flat sheet membrane filter. As a result, the temperature of the stock solution in the pressure vessel rises to such an extent that the properties of the stock solution are adversely affected. In a conventional flat sheet membrane filter,
An operator monitors the temperature of the stock solution at the outlet of the pressure vessel and manually controls the rotation speed of the flat membrane or the stirring plate so that the temperature of the stock solution in the pressure vessel does not exceed a predetermined value.

[0003]

In the conventional flat sheet membrane filtration machine, since the temperature of the stock solution in the pressure vessel was manually controlled, it was difficult to always maintain the temperature of the stock solution at an appropriate value. . Further, since the rotation speed of the flat film or the stirring plate is manually controlled, the load fluctuation of the motor for driving the flat film or the stirring plate tends to be large. Particularly during high-concentration operation, the viscosity of the undiluted solution rapidly increases, so that manual rotation speed control cannot be performed in time, and there is a risk that a current that exceeds the rated value will flow and the filter will stop.
Further, manual temperature control of the stock solution cannot cope with variations in viscosity due to different lots of the stock solution, which may lead to a situation in which the quality of the permeated solution differs from lot to lot. The present invention has been made in view of the above problems, the temperature of the stock solution in the pressure vessel can always be maintained at an appropriate value, and the motor for driving the flat membrane or the stirring plate accompanying the temperature control of the stock solution is excessive. It is an object of the present invention to provide a flat sheet membrane filtration machine capable of suppressing load fluctuations and causing no variation in permeated liquid quality due to difference in stock solution lots.

[0004]

In order to solve the above-mentioned problems, in the present invention, in a rotary flat membrane filter for performing cross-flow filtration of a stock solution by rotating a flat membrane in a pressure vessel, a pressure vessel Provided is a rotary flat sheet membrane filtration device comprising means for detecting the temperature of the stock solution at the outlet and means for controlling the rotation speed of the flat membrane so that the temperature of the stock solution at the outlet of the pressure vessel does not exceed a predetermined value. Further, in the present invention, a flat membrane filter is fixed in a pressure vessel, and a fixed flat membrane filter for performing cross-flow filtration of a stock solution by rotating a stirring plate parallel to the flat membrane in the pressure vessel, (EN) Provided is a fixed flat membrane filter equipped with means for detecting the temperature of the stock solution at the outlet of the pressure vessel and means for controlling the rotation speed of the stirring plate so that the temperature of the stock solution at the outlet of the pressure vessel does not exceed a predetermined value. . Instead of the means for detecting the temperature of the stock solution at the outlet of the pressure vessel and the means for controlling the rotation speed of the flat plate or stirring plate so that the temperature of the stock solution at the outlet of the pressure vessel does not exceed a predetermined value, a flat film or A means for detecting the torque of the motor for rotating the stirring plate, and a means for controlling the rotation speed of the flat film or the stirring plate so that the torque of the motor for rotating the flat film or stirring plate does not exceed a predetermined value. May be provided, or a means for detecting the power consumption of the motor for rotating the flat film or the stirring plate and the power consumption of the motor for rotating the flat film or the stirring plate should not exceed a predetermined value. A means for controlling the rotation speed of the flat film or the stirring plate may be provided.

[0005]

According to the present invention, the rotary flat membrane filter or the fixed flat membrane filter has means for detecting the temperature of the stock solution at the outlet of the pressure vessel and the temperature of the stock solution at the outlet of the pressure vessel to a predetermined value. Therefore, the temperature of the stock solution in the pressure vessel is automatically maintained at an appropriate value without relying on human hands. Means for detecting the torque of the motor for rotating the flat film or stirring plate, and controlling the rotation speed of the flat film or stirring plate so that the torque of the motor for rotating the flat film or stirring plate does not exceed a predetermined value. By providing a means to
Alternatively, a means for detecting the power consumption of the motor for rotating the flat film or the stirring plate and a rotation of the flat film or the stirring plate so that the power consumption of the motor for rotating the flat film or the stirring plate does not exceed a predetermined value. By providing the means for controlling the number, similarly to the above, the temperature of the stock solution in the pressure vessel can be automatically maintained at an appropriate value without relying on human hands.

[0006]

EXAMPLE A fixed flat sheet membrane filter according to an example of the present invention will be described below. As shown in FIG. 1, the fixed flat sheet membrane filter according to the embodiment of the present invention includes a fixed flat sheet membrane module 10. The fixed flat membrane module 10 includes a pressure vessel 11 containing a circular fixed circular plate-shaped ceramic fixed flat membrane (not shown), a stirring plate (not shown) parallel to the fixed flat membrane, and a motor 12 for rotating the stirring plate. , And an inverter 13 for controlling the rotation speed of the motor 12. A stock solution tank 20 for storing a stock solution which is a liquid to be filtered is provided with a jacket 21 for heat exchange on an outer surface of a lower portion thereof. Inside the stock solution tank 20, a stirrer 22 for accelerating heat exchange is arranged.

The lower end of the stock solution tank 20 communicates with the lower end of the pressure vessel 11 via a pipe 30. A circulation pump 31 is provided in the middle of the pipe 30. The upper end of the stock solution tank 20 communicates with the upper end of the pressure vessel 11 via a pipe 40. On the way of the pipe 40, the pressure vessel 1
A temperature sensor 41, a pressure sensor controller 42, and a pressure adjusting valve 43 are arranged in the vicinity of 1. The ceramic fixed flat membrane contained in the pressure vessel communicates with a permeate storage tank (not shown) via a pipe 50. The operation of the inverter 13 is the control unit 6
Controlled by 0. The control unit 60 has
The temperature signal from the temperature sensor 41 is input, and the control unit 60 outputs a control signal to the inverter 13. The control unit 60 incorporates a feedback control circuit that feed-back controls the operation of the inverter 13 based on the temperature signal from the temperature sensor 41.

The operation of the fixed flat sheet membrane filter according to this embodiment having the above structure will be described. The stock solution stored in the stock solution tank 20 is supplied to the pressure vessel 11 via the pipe 30 by the operation of the circulation pump 31. Under the control of the inverter 13, the motor 12 rotates at a predetermined rotation speed,
The stirrer plate built into the machine rotates at a predetermined speed. As a result, the stock solution in the pressure vessel 11 is agitated, and the stock solution is cross-flow filtered by the ceramic fixed flat membrane contained in the pressure vessel 11. The permeated liquid is sent to a permeated liquid storage tank (not shown) through the pipe 50. The concentrated stock solution is pipe 4
It is returned to the stock solution storage tank via 0. The stock solution circulates in a closed circuit composed of the stock solution tank 20, the pipe 30, the pressure vessel 11, and the pipe 40, and is concentrated to a desired concentration. The pressure control valve 43 is feedback-controlled by the pressure sensor controller 42 so that the pressure vessel 11
The pressure of the undiluted solution in the liquid, and eventually the transmembrane pressure difference of the ceramic fixed flat membrane, is maintained at an appropriate value. Cooling water supplied to the jacket 21 from a cooling water supply source (not shown) and the stock solution tank 2
The stock solution is cooled by heat exchange with the stock solution in 0.
The operation of the stirrer 22 promotes heat exchange between the cooling water and the stock solution.

The operation of the inverter 13, and thus the motor 1
2 and the number of rotations of the stirring plate built in the pressure vessel 11 are based on the temperature signal from the temperature sensor 41, and the control unit 60 controls the temperature of the stock solution in the pipe 40 at the position where the temperature sensor 41 is installed, that is, the pressure. Feedback control is performed so that the temperature of the stock solution at the outlet of the container 11 does not exceed a predetermined value. As a result, the temperature of the stock solution in the pressure vessel 11 is always maintained at an appropriate value. Since the optimum control is repeated at short time intervals, there is no possibility that the load on the motor 12 will greatly change due to the temperature control of the stock solution in the pressure vessel 11. Further, even if the stock solution viscosity suddenly increases during operation, there is no possibility that a current exceeding the rated value will flow in the motor 12, and therefore the fixed flat sheet membrane module 10 will not stop. Further, there is no possibility that the quality of the permeated liquid varies due to the difference in lots of the stock solution.

Considering that there is a constant correlation between the amount of heat generated by the friction between the stirring plate and the stock solution and the torque of the motor 13, as shown by the alternate long and short dash line in FIG. Of the stock solution in the pressure vessel 11 by inputting a torque signal of the motor 12, that is, a signal indicating the torque of the motor 12 to the control unit 60 and performing feedback control of the rotation speed of the inverter 13, and thus the motor 12, based on the torque signal. The temperature of can be maintained at an appropriate value. Further, considering that there is a certain correlation between the amount of heat generated by the friction between the stirring plate and the stock solution and the power consumption of the motor 13, as shown by the chain double-dashed line in FIG. 13b
The power consumption signal from the pressure vessel, that is, a signal indicating the power consumption of the motor 12 is input to the control unit 60, and the rotation speed of the inverter 13 and the motor 12 is feedback-controlled based on the power consumption signal. The temperature of the stock solution in 11 can be maintained at an appropriate value. Although the present invention has been described above with a focus on the fixed flat sheet membrane filter, it goes without saying that the present invention can also be applied to a rotary flat sheet membrane filter. In a rotary flat membrane filter, the rotation speed of the flat membrane is feedback-controlled.

[0011]

As described above, in the present invention, the rotary flat membrane filter or the fixed flat membrane filter respectively has a means for detecting the temperature of the stock solution at the outlet of the pressure vessel and the temperature of the stock solution at the outlet of the pressure vessel. The temperature of the stock solution in the pressure vessel is automatically maintained at an appropriate value without relying on human hands, as it is equipped with means for controlling the rotation speed of the flat membrane or stirring plate so that the temperature does not exceed a predetermined value. It Since the optimum control is repeated at short time intervals, there is no possibility that the load of the motor that drives the flat membrane or the stirring plate will change significantly with the temperature control of the stock solution.
Further, even if the viscosity of the stock solution rapidly increases during operation, there is no possibility that an electric current exceeding the rated value will flow to the motor that drives the flat membrane or the stirring plate, and therefore the filter will not stop. Further, there is no possibility that the quality of the permeated liquid varies due to the difference in lots of the stock solution.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a fixed flat sheet membrane filtering machine according to an embodiment of the present invention.

[Explanation of symbols]

 10 Fixed Flat Membrane Module 11 Pressure Vessel 12 Motor 13 Inverter 13a Torque Meter 13b Power Consumption Meter 20 Undiluted Liquid Tank 21 Jacket 22 Stirrer 30 Piping 31 Circulation Pump 40 Piping 41 Temperature Sensor 60 Control Unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ikuo Itakura 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu City In Totokiki Co., Ltd. (72) Masaki Kitamura 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu No. Totoki Equipment Co., Ltd.

Claims (6)

[Claims] 1. A rotary flat membrane filter for performing cross-flow filtration of a stock solution by rotating a flat membrane in a pressure container, and means for detecting the temperature of the stock solution at the outlet of the pressure container,
And a means for controlling the rotation speed of the flat sheet membrane so that the temperature of the stock solution at the outlet of the pressure vessel does not exceed a predetermined value. 2. A rotary flat membrane filter for performing cross-flow filtration of a stock solution by rotating a flat membrane in a pressure vessel, a means for detecting a torque of a motor for rotating the flat membrane, and a flat membrane. And a means for controlling the number of rotations of the flat membrane so that the torque of the motor for rotating does not exceed a predetermined value. 3. A rotary flat membrane filter for performing cross-flow filtration of a stock solution by rotating a flat membrane in a pressure vessel, a means for detecting power consumption of a motor for rotating the flat membrane, and a flat membrane. And a means for controlling the rotation speed of the flat membrane so that the power consumption of the motor for rotating the flat membrane does not exceed a predetermined value. 4. A stationary flat sheet membrane filter for fixing a flat sheet membrane in a pressure vessel, and rotating a stirring plate parallel to the flat sheet membrane in the pressure vessel to carry out cross-flow filtration of the stock solution. A fixed flat sheet membrane filter equipped with means for detecting the temperature of the stock solution at the outlet and means for controlling the rotation speed of the stirring plate so that the temperature of the stock solution at the outlet of the pressure vessel does not exceed a predetermined value. 5. A fixed flat membrane filter for fixing a flat membrane in a pressure vessel, and rotating a stirring plate parallel to the flat membrane in the pressure vessel to perform cross-flow type filtration of the stock solution. A fixed flat sheet membrane filtering machine comprising means for detecting a torque of a motor for rotating the stirring plate, and means for controlling a rotation speed of the stirring plate so that a torque of the motor for rotating the stirring plate does not exceed a predetermined value. 6. A fixed flat membrane filter for performing cross-flow filtration of a stock solution by fixing a flat membrane in a pressure vessel and rotating a stirring plate parallel to the flat membrane in the pressure vessel. Fixed flat membrane filtration provided with means for detecting the power consumption of the motor for rotating the stirring plate and means for controlling the rotation speed of the stirring plate so that the power consumption of the motor for rotating the stirring plate does not exceed a predetermined value. Machine.