JP2736899B2 - Slurry preparation equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a slurry preparation apparatus for efficiently dispersing powder in water to obtain a uniform slurry.

(Prior Art) Dispersing powders such as cement and bentonite in water to prepare slurries such as cement milk and muddy water is an operation frequently performed in the fields of construction and civil engineering.
In this case, the preparation is usually performed by providing a stirring device having rotary stirring blades in a vertical stirring tank. In this device, a predetermined amount of water is filled in the tank, and the slurry is prepared in such a manner that the powder is charged from above. In doing so, it is impossible to prevent the generation of dust and the deterioration of the working environment.

In addition, since water and a large amount of powder come into contact with each other instantaneously, in the case of powder that is difficult to disperse, the powder immediately sinks or forms so-called lumps at the point where it is thrown, resulting in uniform quality. It was difficult to obtain a stable slurry. Further, in the apparatus of the above-mentioned type, since there is a so-called dead space at the lower end and the like, even if stirring is performed strongly, the effect does not reach the dead space. Sediments and lumps often remained in the space. Further, it is difficult to prepare a large amount of uniform slurry with such an apparatus, and usually, a method of preparing the slurry many times in a batch system and sending it to a large slurry tank installed separately. And it took a long time to prepare the slurry.

Therefore, in order to prepare a large amount of slurry in the shortest possible time, a method of circulating the slurry in the slurry preparation tank with a pump is used, and the circulating flow of the slurry is used as an ejector to absorb and circulate the powder using its suction force. It has also been proposed to contact water and powder in the system. Also,
There has also been proposed a method in which a slurry is continuously adjusted while a constant amount of water is supplied and a fixed amount of powder is supplied to bring water and powder into contact in a pipe.

(Problems to be Solved by the Invention) However, in these methods, the time during which the powder flows in contact with water is short, and the use of a jet mixer or a flow mixer increases the size of the apparatus. There were difficulties. Moreover, since the fluid moves in a laminar flow, the stirring effect is small, and it is difficult to obtain a uniformly dispersed slurry, and the lack of stirring must usually be compensated by a method such as separately stirring in a slurry storage tank. Was. Therefore, conventionally, there has been a demand for the development of a slurry preparation apparatus capable of preparing a uniform slurry in a short time for powders that are difficult to disperse in water such as cement and bentonite. Was.

SUMMARY OF THE INVENTION An object of the present invention is to provide a slurry preparation apparatus which solves the above conventional problems and can prepare a large amount of uniform slurry in a short time.

(Means for Solving the Problems) That is, the present invention relates to (1) a slurry preparation tank, a withdrawal means for extracting a liquid from the slurry preparation tank, and a liquid supplied from the withdrawal means being circulated to the slurry preparation tank. A flow line for supplying a powder for preparing slurry and a slurry liquid to the circulation line at a branch portion, and then colliding the branched liquid flows with each other to join the flow lines. And (2) a slurry preparation tank, a withdrawal means for withdrawing a liquid from the slurry preparation tank, and a slurry supply means for supplying the liquid from the withdrawal means. A circulating line for circulating the liquid to the slurry preparation tank, wherein the circulating line supplies powder for preparing the slurry, and a slurry dispersion promoting means. The slurry preparation apparatus provided, comprising a collision portion for causing the slurry dispersion accelerating means to increase the transfer speed of the slurry and then injecting the slurry from a fine hole to collide with a tube wall, an impact plate, or the slurry. The circulation line has a line provided with a powder supply means separately from the line provided with the pores,
A slurry preparation apparatus characterized in that the slurry in the line is discharged into the slurry injected from the pores.

(Examples) Hereinafter, the present invention will be described in more detail based on examples.

FIG. 1 is a schematic view showing one embodiment of the device of the present invention,
FIG. 2 is a schematic sectional view showing a part of the enlarged view. 1 and 2, reference numeral 1 denotes a slurry preparation tank in which water or slurry 2 is stored. 3
Is the extraction means (pump) connected to the slurry preparation tank 1
The circulation line 4 is connected to this, and a branch line 4 a is provided upstream of this line via a valve 6.
The branch line 4a is provided with a powder supply means 5. Reference numeral 7 denotes a discharge port of the branch line 4a. The powder supply means 5 comprises a powder supply hopper 8, a valve 9 below the hopper 8, and an ejector 10. On the other hand, a valve 11 is provided in the circulation line 4 and a slurry dispersion promoting means 12 is provided downstream thereof.
Is located. This slurry dispersion promoting means 12 is provided with a valve 13,
14 and orifices 15 and 16. 17 is the discharge port, 18
Is a perforated plate provided in the slurry preparation tank 1, and 9 and 21 are valves. Reference numeral 22 denotes a discharge line for the prepared slurry.

When preparing a slurry using the above-mentioned apparatus, the liquid 2 in the slurry preparation tank 1 is drawn out of the tank by the pump 3 and sent out to the circulation line 4 connected to the pump 3. Then, it is sent through a valve 6 to a branch line 4a branched from the circulation line 4. Liquid 2 is in this branch line
The powder is returned from the discharge port 7 into the slurry preparation tank 1 through 4a, and powder is supplied on the way. When powder is supplied, a predetermined amount of powder stored in the powder supply hopper 8 of the powder supply means 5 is sucked by a water flow together with air by the action of the ejector 10 through the valve 9, Water is supplied into the slurry preparation tank 1 from the discharge port 7 in short contact with water. When a predetermined amount of powder in the hopper 8 is supplied into the slurry preparation tank 1 in this manner, the valve 6 of the branch line 4a
Is closed, the valve 11 of the circulation line 4 is opened instead, and the slurry is sent to the slurry dispersion promoting means 12 provided in the circulation line 4 via the valve 11.

As is apparent from FIG. 2, in the slurry branch accelerating means 12, the flow velocity is accelerated by the respective pipe orifices 15 and 16 through the valves 13 and 14 via the branch part, and both slurries collide immediately after passing through the orifice, In this process, the slurry is impacted, and the degree of dispersion of the solid content in the slurry is significantly increased. After the collision, the slurry changes from a closed system up to the orifices 15 and 16 to an open system,
From 17, a uniform slurry is returned to the slurry preparation tank 1. The perforated plate 18 is provided to prevent lumps and sediments in the slurry once supplied from the discharge port 17 from moving to other parts in the slurry preparation tank 1, for example, a dead space. The slurry thus prepared is discharged to the outside from the discharge line 20 via the valve 19, and is used for use.

Incidentally, the method of applying impact to the slurry in the slurry dispersion accelerating means 12 of the present invention is, for example, by closing the valve 14 and passing the slurry through the orifice 15 in FIG. A method may be adopted in which the gas is ejected and collides with the other orifice 16. Further, as will be described later with reference to FIG. 4, the structure may be such that the slurry tube collides with the inner wall of the slurry pipe ejected from the orifice or an impact plate such as a plate, a perforated plate or a wire mesh. In addition, as a method of improving the speed of the slurry flow in order to apply an impact to the slurry, not only using an orifice as shown in the figure, but also reducing the pipe line or using a valve to reduce the speed of the slurry flow. It is also effective to use a structure that can be made high.

The structure of the powder supply means installed in the slurry circulation line 4 is not particularly limited as long as the powder is efficiently supplied into the slurry circulation line 4. That is, there is no problem as long as the structure is such that the powder is sucked into the fluid from the powder storage tank by the flow of the liquid.

FIG. 3 is a sectional view showing the powder supply means. In the figure, 31 is a hopper, 32 is powder stored therein, and 33 is a screw feeder for feeding powder. 34 is a slurry circulation line, and 35 is an ejector. hopper
The powder 32 stored in the 31 is a screw feeder
The liquid is forcibly supplied to the slurry circulation line 34 by the fixed amount by the 33, mixed with the slurry discharged through the ejector 35, and sent to the discharge port (not shown). By using this powder supply device, it is also possible to control the solid content concentration in the slurry from the discharge port to a constant amount.

Note that a structure may be employed in which a powder is simply sucked into the slurry by the action of an ejector using a gate valve or other valves instead of a forced powder supply device such as a screw feeder.

In the present invention, the method of providing the powder supply means and the slurry dispersion promoting means in the slurry circulation line is not limited to that shown in FIG. For example, the structure shown in FIG. 4 of a more preferable specific example can be adopted. This is one in which the powder supply means 5 is incorporated in the dispersion promoting means 12 shown in FIG. 2. Specifically, in FIG. 4, reference numeral 40 denotes a powder supply means, The hopper comprises a valve 43 and an ejector 44 provided below the hopper. Reference numeral 42 denotes powder stored in the hopper 41. Reference numeral 45 denotes slurry dispersion promoting means, and valves 46 and 47 are provided through a branch portion. An orifice 48 is provided downstream of the valve 46, while
The powder supply means 40 described above is located downstream of the valve 47.
A discharge port 49 is provided downstream of the orifice 48. A indicates the inner wall of the pipe against which the jet liquid from the orifice 48 at the upstream of the discharge port 49 collides.

First, the liquid is supplied from the hopper 41 of the powder supply means 40 located downstream thereof via the valve 47 and the powder 42 via the ejector 44 via the valve 43. On the other hand, the liquid having passed through the valve 46 is injected through the orifice 48 and collides with the inside A of the pipe wall of the dispersion promoting means 45. Before the collision, the liquid supplied with the powder is discharged from the orifice 48 to the liquid ejected. Therefore, the powder becomes a slurry dispersed uniformly by the impact colliding with the inside A of the tube wall, and is discharged from the discharge port 49. In addition, the discharge angle of the liquid supplied with the powder into the liquid ejected from the orifice 48 is not limited, but is preferably a direction perpendicular to the ejection direction, so that an impact can be applied. . Also, by employing this method, the time for adjusting the slurry can be significantly reduced.

There are various other modes of installing the powder supply means and the slurry dispersion accelerating means, but in the present invention, it is preferable to install them in parallel even when one pump is used.

In the present invention, the extraction means (pump) connected to the circulation line is not particularly limited as long as slurry can be transported. Also, regarding the installation position,
The pump is not limited to the outside of the slurry preparation tank, and may be installed in the slurry preparation tank using a submersible pump.

(Effect of the Invention) The slurry preparation apparatus of the present invention has poor dispersibility in water,
Particularly suitable for preparing a slurry of powder such as cement, bentonite and the like. In particular, conventional bentonite is liable to form lumps in water and increases in viscosity as it is dispersed in water, so it has been extremely difficult to obtain a uniformly dispersed high-concentration slurry. If an apparatus is used, a bentonite aqueous dispersion having a concentration of 10% or more can be easily prepared. Further, the slurry preparation apparatus of the present invention can prepare a uniform slurry with stable quality in an extremely short time as compared with a conventional apparatus. Also, if the slurry preparation device of the present invention is used,
No dust is generated at the time of the conventional slurry preparation, and the operation is simple. In addition, continuous liquid production is possible.
Further, the whole apparatus can be reduced in size and space can be saved, which is extremely useful in practical use.

In addition, the slurry preparation apparatus of the present invention can quickly prepare a homogeneous slurry.
In the food processing industry, chemical industry and other fields, it can be widely used in the process of dispersing powder in a solvent. Further, the present invention can be applied to a step of dissolving a powder which is hardly soluble in a solvent.

Reference Example Using 50 containers as a slurry preparation tank, a slurry preparation apparatus shown in FIG. 4 was prepared. That is, in FIG. 1, the powder supply means is provided at the position 12. An arcuator (TM type manufactured by Kuma Engineering Co., Ltd.) was used as a powder supply means.

A pressure gauge is installed behind the valves 46 and 47 in FIG. 4 and behind the pump 3 in FIG. 1. The pump is a mono pump (model snake, manufactured by Iwaki Co., Ltd., capacity: 35 to 110 / min (stepless)). , Power 1.5KW × 200V). The pipe is 23.6m
An mφ stainless steel pipe was used, the orifice in the slurry dispersion means 48 was 5 mmφ, and the distance from the orifice 48 to the tube wall A was 60 mm.

Using this apparatus, an experiment was conducted to prepare 100 parts of tap water and 8 parts of muddy water of bentonite (Kunigel V: manufactured by Kunimine Industries Co., Ltd.). Bentonite is supplied at a rate of 1.7 kg / min using an aerator, and water is pumped to 34 / min.
Circulated in minutes. Then, a sample of the slurry was sometimes taken from the container, and its funnel viscosity was measured. Version 50
The following table shows the time required for dropping the entire amount of 0 ml using a funnel viscometer. A circulation time of 0 indicates that a sample was collected from inside the container during the supply of bentonite, and thereafter indicates an elapsed time since then.

Separately, add 8 parts of bentonite to 100 parts of tap water,
Hamilton Beach Mixer (US Scovill, Mode1
936-2, 100W-120V) 50-60Hz, rotation speed about 10,000rpm)
The mixture was stirred for 15 minutes to prepare 500 ml of muddy water. The resulting muddy water had an FV of 27.2 seconds. That is, it was confirmed that a uniform bentonite slurry could be obtained very quickly by the apparatus of the present invention. In addition, when the operation was stopped after 5 minutes and the slurry in the container 1 was discarded, the presence of sediment and lumps in the container was not recognized.

[Brief description of the drawings]

FIG. 1 is a schematic view of one embodiment of the slurry preparation apparatus of the present invention,
FIG. 2 is an enlarged view of the dispersion accelerating means used in the slurry preparation apparatus of FIG. 1, FIG. 3 is a schematic view of one example of the powder supply means, and FIG. It is sectional drawing of the other example provided. DESCRIPTION OF SYMBOLS 1 ... Slurry preparation tank, 2 ... Water or slurry, 3 ... Extraction means, 4,34 ... Circulation line, 4a ... Branch line, 5,40 ... Powder supply means, 6 ... Valve, 7 , 22,49 …… Discharge port, 8,31,41 …… Powder supply hopper, 9 …… Valve, 10,35,44 …… Ejector, 11,21… Valve, 12,45 …… Slurry dispersion 13,14 ... valve, 15,16,48 ... orifice, 17 ... discharge port, 18 ... perforated plate, 19 ... valve, 32,42 ... powder, 33 ... screw feeder, 43,46,47 …… Valve.

Claims (2)

(57) [Claims] 1. A slurry preparation tank, a withdrawing means for extracting a liquid from the slurry preparation tank, and a circulation line for circulating a liquid supplied from the withdrawal means to the slurry preparation tank. After the powder supply means for preparing the slurry and the slurry liquid are once branched at the branch portion, the branched liquid streams collide with each other, and a slurry dispersion promoting means having a flow path for merging is provided. A slurry preparation apparatus. 2. A slurry preparation tank, a withdrawing means for extracting a liquid from the slurry preparation tank, and a circulation line for circulating the liquid supplied from the withdrawal means to the slurry preparation tank. Powder supply means for preparing a, and a slurry preparation device provided with a slurry dispersion promoting means, wherein the slurry dispersion promoting means increases the transfer speed of the slurry, and then ejects from the fine holes , A pipe wall, an impact plate or a collision portion for colliding with the slurry, the circulation line has a line provided with a powder supply means separately from the line provided with the pores, the slurry of the line is A slurry preparation apparatus characterized in that the slurry is discharged into the slurry jetted from the pores.