JPH0780270A - Dispersion device for flowable substance and control thereof - Google Patents

Abstract

PURPOSE:To well perform dispersion being a discontinuous phenomenon and to prevent the clogging of a dispersion device by operating the dispersion device non-steadily. CONSTITUTION:A gas blowoff port 4 is formed in a stirring tank 2 and the amt. of the gas blown out of the gas blowoff port is made non-steady. Therefore, a dispersion device can be stabilized under wide conditions and enhanced in its capacity. This dispersion device is especially effective in such a case that the flocculation force of a dispersing medium or a substance to be dispersed is strong or the flowability thereof is inferior.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an apparatus for dispersing a liquid, a gas or a solid in a liquid, a gas or a layer of solid particles and a control method thereof.

[0002]

2. Description of the Related Art A substance intended for dispersion is blown into a substance for the purpose of dispersing another substance, and a means for improving the dispersion performance is to change the shape of the outlet of the substance to be dispersed. Most of them are mechanically redispersed, such as blades that rotate after exiting the outlet for improvement or dispersion.

As the closest example known before the application of the present invention, as described in Japanese Patent Publication No. 57-60892, there is provided a storage part and an outlet for the substance to be dispersed, and the outlet is moved. A redispersion device has been proposed which prevents the formation of a specific flow path of the dispersion target substance. But,
Nothing is described about the operation method for changing the amount of the dispersion target substance in a non-steady state.

[0004]

When a gas, a liquid or a solid particle is blown into a liquid or gas or a solid particle layer such as a reaction tank of a chemical plant or a distillation tower for the purpose of mixing the two, the purpose of the dispersion in the dispersion device is to be improved. There are problems such as clogging of substances and so-called channeling, in which the substance to be dispersed deviates at high speed due to uneven distribution of the substance to be dispersed. In addition, as the outlet of the dispersion target substance is made more porous to improve the dispersion performance, the outlet performance is better and the range of the flow rate is limited, and the clogging of the dispersion substance in the dispersion device becomes more severe. The problem is that the outlets that actually spout out are biased.

[0005] When a substance is stagnated in the apparatus, not only the performance of the apparatus is deteriorated, but also when the stagnant time becomes long, the substance is deteriorated and even the subsequent removal becomes difficult. In addition, the substance that has deteriorated in the device has an adverse effect on the subsequent steps by exiting from the outlet. Stagnation of the material in the device must be avoided for a long time so as to cause a large deterioration.

When an inertial force is used for the dispersion like spraying, the performance cannot be exhibited by reducing the flow rate.
Further, when a large flow rate is applied to a large flow rate, the change in performance is small even if the cohesive force of the liquid increases. In such a case, it is necessary to control the average flow rate while dispersing at a high flow rate.

On the other hand, when a substance having good fluidity such as gas is blown into a substance having poor fluidity, a cylindrical flow path is formed in the substance having poor fluidity, and the substance blown into the tubular flow passage is energized. There are times when you do not get the dispersion performance that you expected because you often missed it.

The inventor of the present invention eliminates the instability of the performance of the dispersion device which continuously supplies the dispersion target substance.
In order to stably improve the dispersion performance in a wide range of conditions, we considered a dispersive phenomenon and considered an unsteady disperser and operating method.

One object of the present invention is to disperse the substance collected outside each portion of the dispersing device and the outlet thereof by intermittently increasing the flow rate of the dispersing target substance and separating it by its inertial force and fluid force. It is to provide a dispersion device.

Another object of the present invention is to provide a dispersion device capable of intermittently reducing the flow rate of the dispersion target substance so as to prevent the dispersion target substance gathering outside the dispersion device from being finely cut off. It is to be.

[0011]

In order to achieve the above object, according to the present invention, the amount of the dispersion target substance discharged is controlled non-steadily.

[0012]

According to the present invention, when a part or all of the dispersion target substance is stagnated in the device through which the dispersion target substance is guided to the outlet or the outlet thereof, the stagnant portion is temporarily increased by temporarily increasing the flow rate of the dispersion target substance. Can be fluidized. In this case, if the flow rate is changed in a shocking manner, the inertial force can be used to flow the stagnant portion with less energy than constantly maintaining a large flow rate. Since it is possible to limit the time for which is increased, it is possible to operate with the average flow rate reduced.

Further, according to the present invention, when the dispersion performance of the dispersion target substance at the outlet depends on the flow rate of the dispersion target substance, when the flow rate of the dispersion target substance is operated at a flow rate at which the outlet performance is good and when the flow rate is narrowed. By repeating the above, the average flow rate can be adjusted while making use of the performance of the outlet of the dispersion target substance.

Further, according to the present invention, for example, so-called channeling which occurs when a fluid having a small flow resistance such as a gas is dispersed in a fluid having a large flow resistance such as in a highly viscous liquid, When a steady flow path of the dispersion target substance is generated and the dispersion target substance passes through it at a high speed to lower the dispersion performance, the dispersion flow rate of the dispersion target substance is changed to achieve steady dispersion. It is possible to prevent the flow path of the target substance from being generated and improve the dispersion performance.

Further, according to the present invention, among the outlets of the dispersing device having a plurality of outlets for the dispersion target substance, by switching the outlets through which the dispersion target substance emerges, the amount of the dispersion target substance emitted through one outlet Can be non-stationary.

[0016]

FIG. 1 is a sectional view showing an embodiment of an agitating device for a highly viscous liquid according to the present invention. The stirring device 1 includes a stirring tank 2 and a stirrer 3 having a stirring blade 301 at the tip. A plurality of conduits 8 are provided below the stirring tank 2, and the gas distributed by the distributor 5 is alternately discharged from the outlet 4 of each conduit. This gas is supplied from the gas tank 7 to the distributor via the pump 8. As the pump 8, a pump whose flow rate can be adjusted up and down by increasing and decreasing the rotation speed is used.

Reference numerals 9, 10, and 11 are pressure gauges,
Electric signals corresponding to the pressure are generated, and these electric signals are transmitted to the controller 6. The average flow rate indicator 12 exchanges data with the controller 6, and the controller 6
To the control target, and receives a control target change command from the controller 6. The control target is also set by a manual input by the operator or the signal 14 of the dissolved gas measuring element. The controller 6 calculates the signals from the pressure gauges 9, 10 and 11 and the target value of the average flow rate from the average flow rate indicator 12 to change the operating speed of the gas pump 8 and the switching interval of the distributor 5. The rotation speed of the gas pump can be adjusted in a wide range, and the switching interval of the distributor is standard,
Be able to take the two stages of low speed.

2, FIG. 3 and Table 1 are characteristic charts showing operating characteristics preset in the controller 6 because the controller 6 operates. In FIG. 2, differential pressure P10-P9
Is the difference between the detected pressure of the contact point 10 provided near the outlet of the tank and the detected pressure of the pressure contact point 9 provided above the outlet. Therefore, the greater the pressure difference, the more agitation inside the tank 2. This means that the liquid has a high density, and the gas, which has a lower density than the liquid, has a poor dispersion. The controller 6 determines that the degree of dispersion is good when the relationship between the differential pressure and the pump rotation speed is in the area a, and determines that the degree of dispersion is bad when the relationship is in the area b.

In FIG. 3, the differential pressure P11-P10 is the difference between the pressure detected by the probe 11 provided in the conduit 8 connecting the pump 8 and the distributor 5 and the pressure detected by the probe 10 provided near the outlet. Therefore, the larger the differential pressure, the more severe the clogging of the gas outlet 4 and the conduit 8. The controller 6 determines that the relationship between the differential pressure and the pump rotation speed is not blocked when the area A is present, and is determined that the relationship is blocked when the relationship is in the area B. Then, in the area C, it is determined that the clogging is severe.

The controller 6 determines that the dispersion is good and is not clogged in FIGS. 2 and 3, that is, the average flow rate when the pressure difference and the pump rotational speed are in the regions a and 3 A of FIG. The pump speed is controlled according to the control target of the indicator 12. At this time, the switching interval of the distributor is standard. This will be called the average flow rate mode. Then, it is considered that there is a minute clogging even in the area A in FIG. 3, and in order to eliminate it, the gas blowing flow rate is temporarily increased when the average flow rate mode continues for a certain time. This interval is determined by the time it takes for the gas or the agitated liquid to degenerate into a problem.

When the driving condition is other than the above, that is, when the driving condition is outside the condition that the driving condition is in both the region a and the region A in FIG. 2, the driving is switched according to the driving style table in Table 1.
The reason why the rotational speed of the pump is increased in the region B in FIG. 3 and the region a in FIG. 2 is to temporarily increase the flow rate and eliminate clogging of the outlet 4 and the conduit 8. When the area C in FIG. 3 is heavily clogged, the pump rotation speed is increased, the switching interval of the distributor 5 is set to a low speed, and the outlet 4 and the conduit 8 connected thereto are blown for each system to cause the clogging. Shall be discharged reliably.

When a highly viscous liquid is aerated, the gas flows out of the once formed gas flow path at a high speed due to its low fluidity and strong cohesive force. The reason why the rotational speed of the pump is lowered in the region A and the region b of FIG. 3 is to close the flow path that is hollowed out by narrowing the flow rate and to stop the channeling phenomenon that causes poor dispersion.

[0023]

[Table 1]

Then, when the number of deviations from the area a in FIG. 2 and the area A in FIG. 3 exceeds a limit within a fixed time, a signal is returned to the indicator of the average flow rate, and the average flow rate is requested to be changed.

FIG. 4 is a cross-sectional view showing an embodiment of the foaming liquid stirring device according to the present invention, in which the dispersion mechanism of the present invention is applied to a defoaming device. The stirring device 31 includes a stirring tank 32,
The stirrer 33 has a stirring blade 331 at its tip. The stirring tank 32 is provided with an inlet 37 in the stirring liquid and a conduit 36 having an opening at the upper part of the stirring tank 32, and an atomizer 35 is attached to the upper opening. A pump 34, which is characterized in that the flow rate pulsates, is attached in the middle of the conduit 36, and the agitated liquid is intermittently caused to flow from the intake port 37 to the atomizer. Further, electrodes 391 and 392 are attached to the upper and lower portions of the stirring tank 32, and an electric resistance meter 38 is provided on an electric wire connecting the electrodes, and the resistance between them is measured by the electric resistance meter 38. When bubbles occur and the upper electrode 391 enters the bubbles, the resistance between the two electrodes decreases. This change in resistance is monitored by the electric resistance meter 38, the resistance value is converted into an electric signal, and the electric signal is sent to the controller 40. Controller 40
Directs the pulsating pump 34 to move when the electrical resistance drops. In addition, in order to prevent the stirring liquid from deteriorating in the pump 34 and the conduit 37, even if the resistance monitored by the electric resistance meter 38 does not decrease, it is operated for a short time at certain intervals.

According to this structure, an atomizer having good dispersion can be used when the flow rate of the pump is temporarily increased, and a single atomizer can defoam a wide range. An atomizer with a large flow rate has advantages such as stable performance against an increase in liquid viscosity and easy attachment of a cleaning mechanism. By using a pulsating pump, energy can be saved as compared with the case where a large flow rate is continuously supplied.

The present invention has been described above with reference to the embodiments, but the present invention is not limited to these and various modifications can be made. For example, it can be applied to a bubble column, a distillation column, and a combustor using powdered fuel.

[0028]

According to the present invention, it is possible to prevent clogging in the dispersion device and at the outlet. In addition, according to the present invention, it is possible to prevent the dispersion target substance from being gathered outside the outlet of the dispersion device or outside the dispersion device due to the poor fluidity of the dispersion medium and the cohesive force of the dispersion target substance. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an aeration and stirring device according to the present invention.

FIG. 2 is a schematic view showing a method for judging the situation of the aeration and stirring device of FIG.

FIG. 3 is a schematic view showing another method of judging the situation of the aeration and stirring apparatus of FIG.

FIG. 4 is a sectional view of a stirring device having a defoaming mechanism according to the present invention.

[Explanation of symbols]

1 ... Stirring device, 2 ... Stirring tank, 3 ... Stirrer, 4 ... Gas outlet, 5 ... Distributor, 6 ... Controller, 7 ... Gas tank, 8 ... Pump, 9, 10, 11 ... Pressure gauge, 12 ...
Average flow rate indicator, 13 ... Exhaust pipe, 14 ... Dissolved gas gauge, 301 ... Stirring blade, 31 ... Stirring device, 32 ... Stirring tank,
33 ... Stirrer, 34 ... Pulsating pump, 35 ... Atomizer, 36 ... Conduit, 37 ... Intake port, 38 ... Electric resistance meter, 39 ... Electrode, 40 ... Controller, 331 ... Stirring blade.

Claims (8)

[Claims] 1. An outlet for a dispersion target substance that guides the dispersion target substance into a dispersion medium having fluidity, a device for guiding the dispersion target substance from a supply source of the dispersion target substance to the outlet, and a flow rate control of the dispersion target substance attached thereto. A dispersion device comprising a device, wherein the flow rate of the dispersion target substance from the outlet of the dispersion target substance can be controlled non-steadily. 2. A conduit having a container containing a fluid dispersion medium and an outlet arranged in the container, the conduit penetrating through the container wall and connected to the outlet, and the suction of the conduit. Dispersion of a fluid substance characterized by comprising a supply source for supplying the dispersion objective substance to the mouth and a control means for controlling the flow rate of the dispersion objective substance passing through the conduit to change the discharge amount from the outlet. apparatus. 3. A fluid substance dispersing apparatus comprising: a container containing a fluid substance, an outlet arranged in the container; and a supply source for supplying a dispersion target substance to the outlet, wherein the conduit is provided. A control method characterized by changing the flow rate of the flow. 4. The control method according to claim 3, wherein a valve is provided in the middle of the conduit and the opening degree of the valve is periodically changed. 5. The control method according to claim 3, wherein the control device comprises a first valve provided in the middle of the conduit and a drive device for periodically changing the opening of the valve.
A control method characterized in that a second valve is attached in series with the above valve and the opening of the second valve is adjusted according to the target value of the average flow rate. 6. The control method according to claim 3, wherein a pump is provided in the middle of the conduit to pulsate the flow rate in the conduit. 7. The control method according to claim 3, wherein the differential pressure between one point in the conduit and one point at substantially the same height as the outlet in the medium container is measured, and when the value exceeds a certain value, it is temporarily set. A control method characterized by increasing the flow rate. 8. The control method according to claim 3, wherein the density in the medium container is measured, and when the density approaches a value before the start of dispersion within a predetermined range, the flow rate is temporarily reduced. Control method.