JP2001070833A - Centrifugal filtration concentrating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a centrifugal filtration concentrating device executing efficient automatic washing in good timing by accurately detecting the generation of dirt and clogging of a filter cloth in order to efficiently execute concentrating treatment for eliminating unnecessary washing and executing washing while rotating a rotary basket in a speed easy to peel the dirt in order to increase washing effect. SOLUTION: An alarm control instrument 22 is connected to a vibration sensor 20 attached at the outer surface of the device body 1. The alarm control instrument 22 compares the amplitude of the vibration detected by the vibration sensor 20 and the standard amplitude, and when the detected value is not less than a set standard value, the control instrument 22 judges that abnormal vibration is generated and washing is necessary, and when the detected value is not more than the set standard value, the control instrument 22 judges that the dirt of the filter cloth is low and washing is unnecessary. A controller 24 following the control instrument 22 outputs a control signal to at least two control means among a sludge supply control device 32, a revolving speed control device 30 and a washing control device 26 and controls a feed pump 33, a washing pump 28 and a driving motor 7 through these devices.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal filtration / concentration apparatus for separating a liquid to be concentrated (stock solution) such as sludge into a concentrated liquid and a separated liquid by centrifugal filtration.

[0002]

2. Description of the Related Art FIG. 9 is a sectional view showing a conventional centrifugal filtration / concentration apparatus. In FIG. 9, reference numeral 1 denotes an apparatus main body comprising a container for collecting a filtrate and a concentrated liquid after solid-liquid separation. The apparatus main body 1 has a filtrate chamber 2 and a concentrate chamber 3, and the filtrate chamber 2 has a filtrate outlet 2a at the bottom, and the concentrate chamber 3 has a concentrate outlet 3a at the bottom. ing.

[0003] Reference numeral 4 denotes a bottomed inverted conical rotating basket rotatably disposed in the apparatus main body 1. The rotating basket 4 is formed of a perforated plate and has a large number of drain holes 4a. . 5 is a filter cloth stretched on the inner peripheral surface of the rotating basket 4, 6 is a stock solution supply pipe for feeding stock solution (sludge) from a stock solution supply pump (not shown) toward the bottom inside the rotating basket 4, Reference numeral 7 denotes a drive motor that drives the rotary basket 4 to rotate. The driving force of the drive motor 7 is controlled by a transmission 9 having a rotation speed adjustment handle 8 for manually adjusting the rotation speed of the rotating basket 4, and pulleys 10 and 11.
It is transmitted to the rotating shaft 13 of the rotating basket 4 via the endless belt 12 stretched between them.

One end 14 is connected to a washing water pump (not shown) for supplying washing water, and the other end is lowered from the upper opening of the rotating basket 4 along the inner peripheral surface to reach the vicinity of the bottom. A washing water pipe 15 is arranged along the length direction of the washing water pipe 14 and is a plurality of washing nozzles for jetting washing water toward the filter cloth 5 at high pressure. As shown in FIG. 10, these washing nozzles 15 are provided so as to project so that washing water can be sprayed from a direction substantially perpendicular to the inner peripheral surface of the filter cloth 5. The washing water pump (not shown), the washing water pipe 14 and the washing nozzle 15 constitute washing means in the above-mentioned centrifugal filtration and concentration device.

Next, the operation will be described. First, the rotating basket 4 is rotated at high speed by the drive motor 7. A stock solution is supplied from a stock solution supply pump (not shown) through a stock solution supply pipe 6 to the bottom of the rotating basket 4 in the high-speed rotation state. The undiluted solution rises on the inner peripheral surface of the filter cloth 5 by the action of the centrifugal force of the rotating basket 4, and the filtrate passing through the filter cloth 5 and the drainage hole 4 a of the rotating basket 4 and the concentrated liquid captured by the filter cloth 5. (High-concentration sludge). After the filtrate flows into the filtrate chamber 2, the filtrate is discharged from the filtrate outlet 2a, and the concentrated solution continues to rise on the inner peripheral surface of the inverted conical rotating basket 4 due to the centrifugal force of the rotating basket 4 to rotate the rotating basket. After flowing into the concentrated liquid chamber 3 from the upper end of 4, the liquid is discharged from the concentrated liquid outlet 3a. For this reason,
A coagulant may be added to the stock solution before it is supplied into the rotating basket 4 to promote solid-liquid separation.

In such a centrifugal filtration / concentration apparatus, when the filter cloth 5 is clogged by solid sludge substances originating from the stock solution, the stock solution supplied into the rotating basket 4 is not filtered, and the stock solution chamber is left as it is. Since it is discharged to 3, the concentration treatment is hindered. In order to eliminate the clogging of the filter cloth 5, the above-described cleaning means is provided.

In an actual operation, the filter cloth 5 gradually becomes clogged with the passage of time, and the effect of the concentration treatment is deteriorated. The clog was cleared. Such a washing process is executed by starting with a preset variable timer and ending after washing for a certain period of time. Usually, the concentration step and the washing step are alternately repeated at regular intervals. In the cleaning process, the supply of the undiluted solution is stopped and the rotating basket 4 is kept rotating. However, since the rotating speed of the rotating basket 4 is manually adjusted, the rotating speed is not changed during the cleaning process. Then, the rotating basket 4 is rotated at the number of rotations during the concentration step.

FIG. 11 is a time chart showing the operation status and the like of a conventional centrifugal filtration and concentration device. As shown in the figure,
The rotation speed of the rotating basket is fixed for manual adjustment,
A step of washing concentration step and T ₂ hours time T ₁ are alternately repeated, when the cleaning device is actuated the supply of stock is stopped.

In such a conventional centrifugal filtration concentrator,
There were the following problems. (1) The washing process using a conventional centrifugal filtration and concentration device is performed using a filter cloth 5
Irrespective of the clogging situation, the processing effect is immediately deteriorated when the filter cloth 5 is severely clogged. Conversely, when the filter cloth 5 is not very clogged, Unnecessary cleaning is performed, and there is a problem that processing efficiency is deteriorated.

(2) In the conventional washing step using the centrifugal filtration / concentration device, even if the filter cloth 5 is not sufficiently washed, the washing is automatically terminated by setting the timer and the next concentration step is started. Therefore, there is a problem that the processing efficiency is not improved.

(3) In the conventional centrifugal filtration / concentration apparatus, if the concentration step is performed without completely eliminating the clogging of (2), if the clogging is unevenly distributed on the inner peripheral surface of the filter cloth 5, the rotating basket 4 has a problem that the centrifugal filtration concentrator has a malfunction such as vibration, which causes a failure.

(4) In the washing step using the conventional centrifugal filtration / concentration apparatus, if the filter cloth 5 itself is forcibly washed without being clogged in the above (2), the power of the washing water supply pump, washing water, etc. However, there was a problem that it was used excessively and was uneconomical.

(5) In the conventional centrifugal filtration / concentration apparatus, since the rotation speed of the rotary basket 4 is adjusted by the manual rotation speed adjusting handle 8, the rotation of the rotary basket 4 in the washing process which is periodically repeated is performed. It is not easy to adjust the number of rotations, and when the filter cloth 5 is washed at the same number of rotations as in the concentration step, a strong centrifugal force acts on the filter cloth 5, and the strong centrifugal force causes the filter cloth 5.
The problem is that even if it is attempted to remove clogging of foreign substances and solid sludge substances pressed against the inner peripheral surface of the filter cloth with the cleaning water sprayed from the inside of the filter cloth 5, the cleaning effect is extremely high, and the cleaning effect is not improved. was there.

(6) In the conventional washing process using a centrifugal filtration / concentration device, the washing is simply repeated periodically. Therefore, the washing time is extended or the washing water pressure is increased. However, there was a problem that it was not possible to determine whether the cleaning was sufficient, and it was not possible to confirm the actual cleaning effect.

(7) In the washing step using the conventional centrifugal filtration / concentration apparatus, since the supply of the undiluted solution is stopped during the washing, no concentration treatment is performed. In this case, the entire operation time is prolonged, which is uneconomical.

[0016]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems. In order to eliminate unnecessary washing and obtain a high-concentration solution more efficiently, it is necessary to remove stains on a filter cloth. It is an object of the present invention to provide a centrifugal filtration / concentration apparatus that accurately detects occurrence of clogging and performs efficient automatic washing with good timing.

Another object of the present invention is to provide a centrifugal filtration / concentration apparatus which performs washing while rotating a rotating basket at a speed at which contaminants (foreign matter) and dirt are easily peeled off from a filter cloth in order to enhance the washing effect. Aim.

[0018]

According to the present invention, there is provided a centrifugal filtration / concentration apparatus comprising: a conical rotating basket provided with a plurality of drain holes; a filter cloth stretched on an inner peripheral surface of the rotating basket; A centrifugal filtration concentrator having a stock solution supply means for supplying a stock solution into a basket, a driving means for rotating the rotating basket, and a washing means for washing the filter cloth,
Concentration measuring means for measuring the sludge concentration of the concentrated liquid discharged from the centrifugal filtration concentrator, supply control means for controlling the operation of the stock solution supply means, and rotation speed control means for controlling the rotation speed of the driving means; A washing control means for controlling the operation of the washing means; and a control means for controlling at least two or more of the supply control means, the rotation speed control means and the washing control means based on the measurement signal of the concentration measuring means. And a controller for outputting a signal.

The centrifugal filtration / concentration apparatus according to the present invention comprises a conical rotating basket provided with a plurality of drain holes, a filter cloth stretched on the inner peripheral surface of the rotating basket, and an undiluted solution in the rotating basket. , A centrifugal filtration concentrator having a driving means for rotating the rotating basket and a washing means for washing the filter cloth, and a concentration for measuring the sludge concentration of the concentrated liquid discharged from the centrifugal filtration concentrator. Measurement means, supply control means for controlling the operation of the stock solution supply means, rotation number control means for controlling the rotation number of the drive means, cleaning control means for controlling the operation of the cleaning means, and concentration measuring means A controller that outputs a control signal to at least two or more of the supply control unit, the rotation speed control unit, and the cleaning control unit based on the measurement signal of It is characterized in.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a partial cross-sectional view showing a configuration of a centrifugal filtration / concentration apparatus according to Embodiment 1 of the present invention. FIG. 2 is a plan view showing vibration measuring means in the centrifugal filtration / concentration apparatus shown in FIG. FIG. 2 is a sectional view showing a washing device in the centrifugal filtration and concentration device shown in FIG. 1. Components of the centrifugal filtration and concentration device according to the first embodiment that are common to the components of the conventional centrifugal filtration and concentration device shown in FIGS. 9 and 10 are denoted by the same reference numerals, and descriptions of those portions are omitted. I do.

The feature of the centrifugal filtration and concentration device according to the first embodiment is that the centrifugal filtration and concentration device is provided with a vibration measuring means for measuring the vibration of the device main body 1 as an index for judging the contamination of the filter cloth 5. As shown in FIGS. 1 and 2, an electrokinetic speed-type vibration detector (hereinafter, referred to as a vibration sensor) 20 as a vibration measuring means is attached to an outer surface of the apparatus main body 1. The vibration sensor 20 is an arrow A ₁ direction and the arrow A shown in FIG. 2
_It detects vibrations in _two directions. This apparatus main body 1 and the drive motor 7 is the structure of the attached stand, tend to vibration increases in the longitudinal direction, ie the arrow A ₁ direction and the arrow A ₂ direction, the difference between normal and abnormal is large This is because it is easy to determine the abnormality.

The vibration sensor 20 has a sensor cable 2
The alarm controller 22 is connected to the control unit 1 via the control unit 1. The alarm controller 22 compares the amplitude (detected value) of the vibration detected by the vibration sensor 20 with a preset amplitude (reference value: for example, a value in the range of 50 μm to 500 μm), and the detected value is If it exceeds the set reference value, it is determined that abnormal vibration has occurred due to dirt or clogging of the filter cloth 5 and it is determined that cleaning is necessary at that time. If the detected value is below the set reference value, This is a determination unit that determines that cleaning is unnecessary at that point in time, assuming that dirt on the filter cloth 5 has been eliminated because the rotation of the rotating basket 4 is stable. A controller 24 is connected to the alarm controller 22 via a signal cable 23. The controller 24 is connected to the controller 24 via a signal cable 25 as a cleaning control means.
6 and a cleaning pump 28 via a cable 27. The controller 24 controls the cleaning control device 26 in accordance with the judgment on the necessity of the cleaning by the alarm controller 22, and activates the cleaning pump 28 at the start of the cleaning process as necessary.

The controller 24 is connected to a rotational speed controller 30 via a signal cable 29. The rotation speed control device 30 is an inverter that electrically increases or decreases the rotation speed of the drive motor 7 that drives the rotation basket 4 to rotate. The rotation speed of the drive motor 7 is reduced by a control signal from the controller 24 during the cleaning process. In the enrichment step, the number of rotations of the drive motor 7 is increased.

Further, a sludge supply control device 32 is connected to the controller 24 via a signal cable 31. The sludge supply control device 32 controls the operation of a supply pump 33 as a stock solution supply means. The supply pump 33 is stopped by a control signal from the controller 24 in the washing step, and is supplied in the concentration step. 33 is operated.

The controller 24 outputs a control signal to at least two or more of the sludge supply control device 32, the rotation speed control device 30 and the cleaning control device 26 based on the measurement data of the vibration sensor 20. The supply pump 33, the cleaning pump 28, or the drive motor 7 is controlled via these components. In the first embodiment, the three control devices are controlled by the controller 24. However, when the rotation speed of the driving unit is not reduced during the cleaning process, the controller 24 controls the supply control device 32 and the cleaning control. Two of the devices 26 may be controlled.

In the first embodiment, as shown in FIG. 3, the direction of the cleaning nozzle 15 constituting the cleaning means is horizontal, so that dirt such as impurities on the filter cloth 5 is shallow. Because the washing water can be sprayed at an angle,
The dirt on the filter cloth 5 can be peeled off in a short time. By making the direction of the washing nozzle 15 horizontal and lowering the rotation of the rotating basket 4 at the time of washing, which will be described later, a synergistic effect on the effect of washing the filter cloth 5 can be obtained.

Next, the operation will be described. In the time chart of FIG. 4 and the flowchart of FIG. 5, when the dirt partially adheres to the inner peripheral surface of the filter cloth 5 in the rotating basket 4 during the concentration operation (step S1 in FIG. 5), the rotating basket 4 The balance is lost and abnormal vibration occurs. This abnormal vibration is detected by the vibration sensor 20. The detected value is sent to the alarm controller 22 and compared with the set value (step S2 in FIG. 5). If the vibration has a larger amplitude than the set value, the filter cloth 5 is washed with dirt requiring cleaning. Is determined to be attached, and an alarm signal is sent to the controller 24. When this alarm signal is input to the controller 24 as the cleaning device start command A as shown in FIG. 4, the controller 24 stops the supply of the undiluted solution (FIG. 5).
Step S3), controlling the inverter 30 to control the rotation speed N
_The number of rotations of the drive motor 7 rotating at ₁ is set to a predetermined value N
₂ (N ₁ > N ₂ ) (step S in FIG. 5).
4) Control the cleaning control device 26 to activate the cleaning pump 28 (step S5 in FIG. 5). These steps S3
Step S5 may be performed simultaneously. At the latest, when the cleaning pump 28 is started, the cleaning time timer is activated (Step S6 in FIG. 5). Cleaning is performed for a predetermined cleaning time T
After only _two were held (step S7 in FIG. 5), the cleaning device is stopped (step S8 in FIG. 5), the rotational speed of the basket 4 is increased from N ₂ to N ₁ (N _1> N ₂₎ (Fig. 5 step S9), the supply of the stock solution is restarted (step S10 in FIG. 5). These steps S8 to S1
0 may be performed simultaneously. Next, when the stock solution to be supplied remains (step S11 in FIG. 5), the process returns to step S2. S
Steps S3 to S11 are executed, but if no undiluted solution remains (step S11 in FIG. 5), a series of concentration processing ends.

As described above, according to the first embodiment, when a vibration equal to or more than the reference value of the apparatus main body 1 is detected as an indicator of dirt on the filter cloth 5, the rotation speed of the rotating basket 4 is reduced. Since the supply of the undiluted solution is stopped and the cleaning device is started, the stain on the filter cloth 5 can be removed in a timely manner. Therefore, unnecessary washing which has been a problem in the conventional centrifugal filtration / concentration apparatus can be reliably eliminated, and dirt and clogging of the filter cloth 5 can be accurately washed, and the concentration treatment can be performed efficiently.

According to the first embodiment, the filter cloth 5
Since the cleaning is performed after the rotation speed of the rotating basket 4 is reduced to a speed at which the dirt is easily removed, the cleaning effect can be remarkably improved.

Further, according to the first embodiment, the number of rotations of the rotating basket 4 is reduced when the abnormal vibration of the rotating basket 4 due to the contamination of the filter cloth 5 is detected. The occurrence of damage to the rotating mechanism can be suppressed, thereby extending the life of the device.

Embodiment 2 FIG. 6 is a sectional view showing a turbidity measuring detector in a centrifugal filtration and concentration device according to Embodiment 2 of the present invention, and FIG. 7 is a plan view showing a washing device in the centrifugal filtration and concentration device according to Embodiment 2 of the present invention. It is. Among the components of the centrifugal filtration and concentration device according to the second embodiment, those that are the same as those of the centrifugal filtration and concentration device according to the first embodiment shown in FIG. Is omitted.

The feature of the second embodiment is different from the first embodiment in that a turbidity measurement detector (hereinafter referred to as a turbidity sensor) 34 for measuring the sludge concentration of the concentrated liquid as an indicator of the contamination of the filter cloth 5 is used. Is provided. The turbidity sensor 34 is disposed so that the probe at the tip thereof is immersed in the concentrate flowing in the concentrate pipe 35 as shown in FIG. Measuring tank (not shown)
May be provided and disposed inside. In addition, the number of measurement points is not limited to one, and it is preferable to use a plurality of points in order to detect an accurate sludge concentration of the concentrated liquid. The turbidity sensor 34
However, a normal turbidimeter or the like can be preferably used, but the present invention is not limited to this. The turbidity meter is a device for measuring the degree of turbidity of the concentrated liquid, and measures the amount of light attenuation in the concentrated liquid by utilizing the property that light is reflected and scattered by sludge particles in the concentrated liquid. .

The turbidity sensor 34 has a sensor cable 3
A turbidity measuring transducer 37 is connected via 6. The turbidity measurement converter 37 compares the turbidity (detected value) detected by the turbidity sensor 34 with a preset reference value, and when the detected value falls below the set reference value, the filtration is performed. It is determined that the cloth 5 is clogged and hinders the concentration process, and it is determined that cleaning is necessary at that time. If the detected value exceeds the set reference value, the filter cloth 5 becomes dirty. It is a determination unit that determines that cleaning is unnecessary at that point in time when the clogging is eliminated. The turbidity measurement converter 34 is connected to the controller 24 that outputs control signals to the cleaning control device 26 and the rotation speed control device 30 shown in FIG.

In the second embodiment, as shown in FIG. 7, the direction of the washing nozzle 15 constituting the washing means is opposite to the direction of rotation of the rotating basket 4, whereby foreign substances on the filter cloth 5 are removed. The impact force of the washing water against the stains such as increases, and the stains can be more quickly and reliably removed. The direction of the cleaning nozzle 15 is simultaneously performed with a low rotation speed of the rotating basket 4 during cleaning, which will be described later, so that a synergistic effect on the cleaning effect on the filter cloth 5 can be obtained.

Next, the operation will be described. The operation of the centrifugal filtration and concentration device according to the second embodiment will be described with reference to the time chart of FIG. 4 and the flowchart of FIG. During the concentration operation (step S1 in FIG. 5), if the detection value of the turbidity sensor 31 is smaller than the reference value (step S1 in FIG. 5).
2), the filter cloth 5 was clogged, so that solid-liquid separation was not sufficiently promoted and the sludge concentration in the concentrated liquid did not increase. In this case, steps S3 to S10 in FIG. 5 are performed to perform a necessary cleaning process. In this case, steps S3 to S5 and steps S8 to S10 may be performed simultaneously. That is, in the second embodiment, the turbidity of the concentrated liquid is used as a trigger for outputting an alarm signal as the cleaning device start command A to the controller 24. next,
If the stock solution to be supplied remains (step S11 in FIG. 5), the process returns to step S2, and if the detected value of the turbidity of the concentrated solution is still less than the reference value at that time, steps S3 to S3 are repeated. Step S11 is executed, but if no undiluted solution remains (step S11 in FIG. 5), a series of concentration processing is ended similarly to the first embodiment.

As described above, in the second embodiment, when it is detected that the turbidity of the concentrated liquid is less than the reference value as an indicator of the stain on the filter cloth 5, as in the first embodiment,
Since the supply of the undiluted solution is stopped, the number of rotations of the rotating basket 4 is reduced, and the cleaning device is started, the stain on the filter cloth 5 can be removed with good timing. Therefore, unnecessary washing which has been a problem in the conventional centrifugal filtration / concentration apparatus can be reliably eliminated, and insufficient concentration of sludge which may occur due to clogging of the filter cloth 5 can be prevented.

According to the second embodiment, similarly to the first embodiment, the filter cloth 5 is washed after reducing the number of rotations of the rotating basket 4 to such a speed as to easily remove dirt from the filter cloth 5. Therefore, the impact force of the washing water on the stain on the filter cloth 5 is increased, so that the washing effect can be remarkably improved.

In the second embodiment, the sludge concentration of the concentrated liquid is measured, but the concentrated separated liquid (filtrate) may be measured. When the concentration treatment is not sufficiently performed due to clogging or the like, the sludge concentration of the filtrate increases. This may be detected and washing may be performed.

Further, in the second embodiment, only the turbidity of the concentrated liquid is used as an indicator of the contamination of the filter cloth 5, but by combining the vibration of the apparatus main body 1 in the first embodiment which is higher than the standard, The determination regarding the necessity of cleaning can be performed with higher accuracy.

In the second embodiment, the turbidity of the concentrated solution is used as an indicator of the stain on the filter cloth 5, but the viscosity increases with the concentration of the concentrated solution, and the viscosity increases with the decreased concentration of the concentrated solution. The viscosity of the concentrated liquid may be used as an indicator of the soiling of the filter cloth 5 because of the lowering of the concentration. In this case, a viscosity sensor (not shown) for measuring the viscosity of the concentrate can be provided in the concentrate measuring tank. That is, the turbidity or viscosity of the concentrated solution is used as an index of the stain on the filter cloth 5 in each case because various substances are contained in the concentrated solution and the concentration itself of the concentrated solution is directly measured. In this sense, the turbidimeter or viscometer constitutes the concentration measuring means of the concentrated liquid or at least a part thereof.

Embodiment 3 FIG. 8 is a time chart showing the operation status and the like of the centrifugal filtration and concentration device according to Embodiment 3 of the present invention. Note that among the components of the centrifugal filtration and concentration device according to the third embodiment, those that are common to the components of the centrifugal filtration and concentration devices according to the first and second embodiments are denoted by the same reference numerals, and the same reference numerals are used. Is omitted.

The feature of the third embodiment is that, in addition to the first and second embodiments in which the number of revolutions of the rotating basket 4 is reduced by the inverter 30 at the time of washing, the rotation of the rotating basket 4 at the time of washing is further improved. The point is that the direction is controlled so as to change at regular intervals.

Next, the operation will be described. Steps until cleaning is started (Steps S1 to S in FIG. 5)
5) and a step of ending the cleaning (steps S8 to S8 in FIG. 5).
Step S11) is basically the same as in the first embodiment or the second embodiment. That is, for example, the vibration sensor 2
When an alarm signal from the alarm controller 22 is input to the controller 24 as the cleaning device start command A based on 0 or the vibration or turbidity of the turbidity sensor 34, the controller 2
4 stops the supply of the stock solution (step S3 in FIG. 5), the rotational speed of the drive motor 7 which rotates at a rotational speed N ₁ and controls the inverter 30 to a predetermined value _{N 2 (N 1> N 2} ) The cleaning pump 28 is started by controlling the cleaning control device 26 (step S4 in FIG. 5).
5).

As shown in FIG. 8, in the cleaning step, a timer is activated at the same time as the start of the cleaning step, and the controller 24 controls the inverter 30 at regular time intervals (T ₃ ) to change the rotation direction to forward, reverse or forward. Inversion and reversal are repeated several times.
Here, the forward rotation refers to the rotation direction of the rotating basket 4 in the concentration step, and the reverse rotation literally refers to the opposite rotation of the forward rotation. N _1, N ₂ in FIG. 8 shows the absolute value of the rotational speed, both have a relationship of N _1> N _2. In addition, since the parameters such as abnormal vibration, turbidity, or viscosity measured as an index of the contamination of the filter cloth 5 can be effectively used for the determination at the time of shifting from the washing step to the concentration step, the washing is performed. After confirming the effect, the process can proceed to the concentration step.

As described above, in the third embodiment, in addition to the effects of the first or second embodiment, the rotation direction of the rotating basket 4 is controlled to be reversed at regular intervals during cleaning. Thereby, it is possible to wash the filter cloth at a lower rotation speed, and further to apply a further impact force to the dirt on the filter cloth 5 at the time of reverse rotation, so that regardless of the installation direction of the nozzle, Since the stain on the filter cloth 5 can be reliably removed, the cleaning effect can be significantly improved.

[0046]

As described above, according to the present invention, when the abnormal vibration of the apparatus main body or the turbidity or viscosity of the concentrated solution is detected as an indicator of the contamination of the filter cloth, the supply of the undiluted solution is stopped, and the rotation is stopped. Since the number of rotations of the basket is reduced and the cleaning device is activated, it is possible to efficiently remove dirt from the filter cloth in a timely manner. Therefore, unnecessary washing which has been a problem in the conventional centrifugal filtration / concentration apparatus can be reliably eliminated, and dirt and clogging of the filter cloth can be accurately washed, and the concentration treatment can be performed efficiently.

According to the present invention, since the washing is performed after the number of rotations of the rotating basket is reduced to a speed at which the stain on the filter cloth is easily removed, the impact force of the washing water against the stain on the filter cloth is increased. Therefore, the cleaning effect can be remarkably improved, whereby the waste of cleaning water and electric power can be suppressed, and the overall operation time can be shortened.

According to the present invention, the number of revolutions of the rotating basket is reduced when abnormal vibration of the rotating basket due to the contamination of the filter cloth is detected. Can be suppressed, and the life of the device can be extended.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a configuration of a centrifugal filtration / concentration apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a plan view showing a vibration measuring means in the centrifugal filtration and concentration device shown in FIG.

FIG. 3 is a sectional view showing a washing device in the centrifugal filtration and concentration device shown in FIG. 1;

FIG. 4 is a time chart showing an operation state and the like of the centrifugal filtration and concentration device shown in FIGS. 1 and 3;

FIG. 5 is a flowchart showing an operation state and the like of the centrifugal filtration and concentration device shown in FIGS. 1 and 3;

FIG. 6 is a sectional view showing a turbidity measuring detector as a concentration measuring means in the centrifugal filtration and concentration device according to the second embodiment of the present invention.

FIG. 7 is a plan view showing a washing device in a centrifugal filtration / concentration device according to Embodiment 2 of the present invention.

FIG. 8 is a time chart showing an operation state and the like of a centrifugal filtration / concentration apparatus according to Embodiment 3 of the present invention.

FIG. 9 is a partial cross-sectional view showing a conventional centrifugal filtration and concentration device.

FIG. 10 is a sectional view showing a washing device in the centrifugal filtration and concentration device shown in FIG. 9;

FIG. 11 is a time chart showing an operation state and the like of the centrifugal filtration and concentration device shown in FIGS. 9 and 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Device main body 2 Filtrate chamber 2a Filtrate discharge port 3 Concentrate liquid chamber 3a Concentrate discharge port 4 Rotating basket 4a Drainage hole 5 Filter cloth 6 Raw material supply pipe 7 Drive motor 8 Rotation speed adjustment handle 9 Transmission 10 and 11 Pulley 12 Endless belt DESCRIPTION OF SYMBOLS 13 Rotating axis 14 Cleaning water pipe 15 Cleaning nozzle 20 Vibration sensor (vibration measuring means) 21 Sensor cable 22 Alarm controller 23, 25, 29 Signal cable 24 Controller 26 Cleaning control device (cleaning control means) 27 Cable 28 Cleaning pump (cleaning means) 30) Revolution control device (revolution control device) 31 Signal cable 32 Sludge supply control device (supply control device) 33 Supply pump (raw liquid supply device) 34 Turbidity sensor (concentration measurement device) 35 Concentrated liquid pipe 36 Sensor cable 37 Turbidity measurement transducer

Continued on the front page F term (reference) 4D057 AA11 AB01 AC02 AC06 AD01 AE02 AF03 BA36 CA06 CB00 CB01 CB04 4D059 AA00 BE19 CB17 EA20 EB02 EB20

Claims (2)

[Claims] 1. A conical rotating basket provided with a plurality of drain holes, a filter cloth stretched on an inner peripheral surface of the rotating basket, a stock solution supply means for supplying a stock solution into the rotating basket, and the rotating basket. A centrifugal filtration concentrator having a driving means for rotating the filter cloth and a washing means for washing the filter cloth; a vibration measuring means for measuring a vibration caused by the rotation of the rotating basket; and a supply control means for controlling the operation of the stock solution supplying means. Rotation speed control means for controlling the rotation speed of the driving means; cleaning control means for controlling the operation of the cleaning means; supply control means based on a measurement signal of the vibration measurement means; and rotation speed control means. And a controller for outputting a control signal to at least two or more of the washing control means. 2. A conical rotating basket provided with a plurality of drain holes, a filter cloth stretched on an inner peripheral surface of the rotating basket, a stock solution supply means for supplying a stock solution into the rotating basket, and the rotating basket. A centrifugal filter / concentrator having a driving unit for rotating the filter cloth and a washing unit for washing the filter cloth; a concentration measuring unit for measuring a sludge concentration of a concentrated liquid discharged from the centrifugal filtration / concentrator; Supply control means for controlling the number of rotations of the driving means; cleaning control means for controlling the operation of the cleaning means; and the supply control means based on a measurement signal of the concentration measurement means. And a controller for outputting a control signal to at least two or more of the rotation speed control means and the washing control means.