JP2000000450A - Jet mixer and granular body supply method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a jet mixer and granular body supply method by which the formation or growth of a deposit is prevented by devising the granular body supply method, and consequently, a paste efficiently produced or a desired- quality paste is continuously and stably produced. SOLUTION: A granular body S is withdrawn from a granular body inlet 4a by the back pressure of the high-speed water current W running in a power tube 3 and collided with the inner face of the cyclone 6 at the tip of the power tube, hence the granular body and water are agitated and mixed, the paste in a desired water/granular body ratio is obtained by this jet mixer. In the mixer, a granular body supply equipment is provided, and the equipment is furnished with a hopper 5a for storing the granular body, an aerator 10 for imparting high fluidity to the granular body in the hopper, a granular body feed regulator 20 arranged at the hopper outlet and a feeder 5b for dropping the granular body and supplying it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jet mixer for mixing and stirring powders and granules by a high-speed jet water stream to continuously produce a paste and a method for supplying the powders and granules.

[0002]

2. Description of the Related Art As a method for producing a paste by mixing and stirring water and a granular material such as cement, coal ash, blast furnace slab, lime, etc., besides a mechanical mixing method using rotating blades, it is also called a power tube. There is a jet mixer in which a high-speed jet water stream is passed through a pipe to be added, and powder and granules are added thereto to produce a paste.

As shown in FIGS. 4, 5 and 6, the structure of this jet mixer is as follows: a high-pressure pump 1 for producing a jet water flow, a nozzle 2 for generating a jet water flow W, a power tube 3 through which the jet water flow W passes, and a power A hopper 4 having a powder material inlet 4a into the tube 3, a powder material supply facility 5 having a storage hopper 5a for the powder material S and a screw feeder 5b, and a cyclone 6 serving as a container for receiving the paste
And the like.

[0004] The jet water stream W coming from the rear end of the power tube 3 sucks the granular material S at a negative pressure (back pressure) similarly to the spraying, and the granular material S is mixed with the granular material S at the inlet 4a of the granular material S. Water W
And violently collide.

The mechanism by which stirring and mixing can be performed by a jet mixer is that a turbulent water flow generated in the power tube 3 entrains and agitates the powder and granules, and the paste jetted from the tip of the power tube 3 collides with the cyclone 6. This is because the kneading method (kneading) proceeds by applying a shearing force to the inside of the paste itself due to the fluid pushing force that the paste itself adheres to the inner surface of the cyclone 6.

[0006]

The jet mixer has a simple structure and has an advantage that it has a structure for continuously producing a paste. However, the greatest weak point is that the jet mixer is used in the power tube 3 or the powder or the like. This is a problem that deposits are generated near the mouth 4a. The particles S adhere to the moisture caused by the jet stream, and adhere to the inside of the power tube 3, the particle inlet 4 a, the inner surface of the hopper 4, and the like, so-called snowing, which gradually develops. It grows and forms as a deposit.

[0007] Specifically, as shown in FIGS. 7 and 8, the place where the deposits are generated is a hopper in contact with the inner surface (a) of the power tube 3 near the powder material inlet 4 a and the powder material inlet 4 a. 4 is an arcing phenomenon (c) of the powder and granular material S in the hopper due to the deposits on the inclined surface (b) of the outlet and the inclined surface (b) of the outlet of the hopper 4. It is considered that this arching phenomenon is actually caused mainly by the intermeshing between the particles themselves and the friction with the inner surface of the hopper.

[0008] As described above, if there is a deposit on each of the parts (a), (b), and (c), it becomes difficult to supply the granular material S gradually, and finally the granular material input port 4a is clogged. Problem arises. Even if it is not clogged, the supply amount of the granular material S per unit time changes according to the growth of the attached matter, so that the water content of the obtained paste also changes, and the desired fluidity paste cannot be obtained. Problems arise. Therefore, conventionally, in order to cope with such a problem, it is necessary to remove and clean the attached matter each time, and accordingly, the productivity is reduced accordingly.

The present invention has been made in consideration of the above points, and by devising a method of supplying a granular material,
A jet mixer which can prevent the attachment or prevent the growth of the attachment, thereby improving the efficiency of the paste production and continuously and stably producing the paste of the desired quality; and It is an object to provide a method for supplying a granular material.

[0010]

In order to solve the above-mentioned problems, according to the present invention, a granular material is drawn from a granular material inlet by a back pressure of a high-speed water flow running in a power tube, and a cyclone at a tip portion of the power tube is provided. In a jet mixer which obtains a paste having a desired water / granule ratio by stirring and mixing the granules and water by colliding with the inner surface, a granule supply facility is provided. A storage hopper for accommodating powders and granules, an aeration device for providing high fluidity to the powders and granules in the storage hopper, a supply / amount adjusting device for the powders and granules disposed at an outlet of the storage hopper, And an input device for supplying the input device while dropping it toward the input port. Thus, the powder can be guided to the powder inlet while flowing and falling like a liquid, and the flow of the powder can be controlled.

Here, it is also very suitable to set the inner surface of the power tube and the inner surface near the powder material inlet to 0.1 μm or less in surface roughness. In this case, a coating layer having a surface roughness of 0.1 μm or less may be applied to the inner surface of the power tube and the inner surface near the powder material inlet. Then, since the surface friction coefficient becomes extremely small, the powder particles hardly adhere, and even if they adhere, they fall off easily.

On the other hand, according to the present invention, the step of drawing in the powder and granules in the hopper from the inlet of the powder and granules by the back pressure of the high-speed water flow running in the power tube, A method of supplying powder to a hopper by jetting a powder having a desired water / powder ratio by stirring and mixing the powder and water with the step of colliding the powder with the inner surface. A step of supplying air to the body to increase the fluidity of the powder and granules, and a step of dropping the powder with the increased fluidity toward the powder and grain inlet are performed. According to this method, it is possible to fundamentally remove the phenomenon that the powdery particles adhere to the flow path.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall configuration diagram of a jet mixer according to the present embodiment. 2 and 3 are enlarged cross-sectional views of the main part, FIG. 2 is a partial cross-sectional view of an aeration apparatus, and FIG. 3 is a continuous portion of a power tube and a hopper. In these figures, for the sake of convenience, the same components as those of the jet mixer shown in FIGS.
The same reference numerals are given.

The jet mixer according to the present embodiment has
As shown in FIG. 1, a high-pressure pump 1 for creating a jet water flow
And the nozzle 2 for generating the jet water flow W (see FIG. 6)
A power tube 3 through which the jet water stream W passes, and a hopper 4 having a powder material inlet 4a into the power tube 3.
It is the same as the related art in that it includes a powder and granular material supply facility 5 having a storage hopper 5a for the powder and granular material S and a screw feeder 5b, and a cyclone 6 as a container for receiving the paste.

However, in the present embodiment, the powdery and granular material supply equipment 5 is particularly characterized. That is, the powder supply apparatus 5 is an aeration apparatus 1 for supplying air to the powder S in the storage hopper 5a to give high fluidity.
0 is provided.

The aeration apparatus 10 includes a plurality of blowing sections 11 for blowing compressed air to the inner surface of the inclined plate 5c of the storage hopper 5a, and a supply source 1 such as an air pump.
And 2. The blowing unit 11 is, as shown in FIG.
An opening 5d formed in the slope plate 5c and the opening 5d
A permeable material 11a made of a nonwoven fabric or the like loaded in the inside, and a punched metal 1 covering the permeable material 11a from outside.
1b and a cover plate 1 forming an air chamber 11c outside thereof
1d. The cover plate 11d has a pipe 13 for guiding air from the supply source 12 to the air chamber 11c.
Is connected.

Further, between the storage hopper 5a and the screw feeder 5b, there is provided a powder / particle supply adjusting device 20 comprising a rotary feeder. The rotary feeder 20 is provided to have a function of controlling the flow of the granular material S in the storage hopper 5a and a function of supplying the granular material S in a required amount according to a required amount. . That is, the supply of the granular material S can be stopped by adjusting and stopping the flow rate of the granular material S sent to the screw feeder 5b according to the rotation speed of the rotary feeder 20.

Further, it is designed so that the granular material S transferred by the screw feeder 5b can be supplied to the hopper 4 by dropping it toward the inlet 4a. Therefore, the hopper 4 here has a function of guiding the powder S to be dropped from the screw feeder 5b toward the inlet 4a and a function of preventing scattering, etc., instead of storing the powder inside the hopper 4. And shape.

As described above, by dropping the granular material S and charging the same, the flowing operation of the granular material S is not stopped, and the granular material S is continuously and smoothly flowed like a fluid, so that the charging port 4a is formed.
Can be supplied directly to As a result, it is possible to effectively prevent the occurrence of an arching phenomenon due to adhesion near the inlet 4a.

Further, in this embodiment, as shown in the enlarged view of FIG. 3, the inner surface of the power tube 3 and the hopper 4
Of the flow path of the granular material S from the inside to the power tube 3, at least an inner surface portion near the granular material input port 4 a is provided with a coating layer C having a smaller surface friction coefficient than other portions. I have.

As a material of the resin coating layer C, for example, a resin material such as Teflon can be used. The coating layer C made of this resin material has a surface roughness of 0.1 μm or less and has a low friction coefficient. Therefore, on the surface of the coating layer C, the powder S
Deposits due to the relationship between water and moisture are unlikely to adhere, and even if they adhere, the surface of the coating layer C is smooth and easily falls off due to slight vibration or the force of a jet water flow.

The surface roughness of the coating layer C is preferably as small as possible, for example, more preferably about 0.05 μm. According to the experimental results, 0.1μ
When it exceeds m, it has been found that adhesion progresses due to friction and it is difficult to drop.

If, for example, during continuous operation, clogging occurs due to deposits, the supply of the granular material S is temporarily stopped, the inside of the power tube 3 is cleaned by applying only the jet water flow, and then again. A method of restarting the operation may be used. Even in such a case, it is easy to remove the deposits because the surface roughness is small.

By the way, from the viewpoint of reducing the surface friction coefficient of the flow path of the granular material so as to make it difficult for the deposits to adhere, the material constituting the jet mixer itself is selected instead of the coating layer C. It can also be solved. For example, power tube 3 and hopper 4
This is a method of using stainless steel (having a surface roughness of 0.1 μm or less) having a smaller surface friction coefficient than a general steel pipe or the like. Stainless steel itself is particularly effective because it also has excellent wear resistance. Of course, the surface part having a low coefficient of friction can also be obtained by so-called mirror finishing only a necessary part.

However, from the viewpoint of material costs, production costs, etc., only the power tube 3 is made of stainless steel, and the hopper 4 is made of a normal material, and a so-called combination method of applying a coating layer C to a required surface portion is adopted. It is also effective to do so.

When adopting the method of applying the coating layer C, as shown in FIG. 3, it is very preferable to apply the coating from the entire inclined surface 4b near the outlet of the hopper 4 to the vertical rising portion 4c. This is because the granular material S can slip easily under its own weight, including the boundary portion from the inclined surface 4b portion to the vertical rising portion 4c portion, by its own weight, thereby further suppressing the generation of attached matter. Because.

[0027]

As described above, according to the present invention, air is supplied to the granules to be supplied to the hopper to increase the fluidity of the granules, and the granules having the enhanced fluidity are powdered. Since the powder is supplied by being dropped toward the granule input port, the phenomenon that the granules adhere to the flow path can be fundamentally removed. That is, it is possible to prevent the attachment or prevent the growth of the attachment, whereby the efficiency of the paste production and the paste of the target quality can be continuously and stably produced.

Further, the inner surface of the power tube and at least the inner surface near the powder material inlet of the inner surface of the flow path of the powder from the hopper to the inside of the power tube are
Since the surface roughness is set to 0.1 μm or less, it is possible to prevent the attached matter from being attached or prevent the attached matter from growing.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a jet mixer according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of an air blowing section of the jet mixer according to the embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view near a charging port of the jet mixer according to the embodiment of the present invention.

FIG. 4 is an overall configuration diagram of a jet mixer showing a conventional example.

FIG. 5 is a plan view of a conventional jet mixer.

FIG. 6 is a sectional view taken along line AA of FIG. 1, showing a nozzle.

FIG. 7 is an explanatory diagram showing a state of a deposit.

FIG. 8 is a sectional view taken along the line BB of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High-pressure pump 2 Nozzle 3 Power tube 4 Hopper 4a Powder inlet 4b Inclined surface part 4c Vertical rising part 5 Powder supply unit 5a Storage hopper 5b Screw feeder 6 Cyclone 10 Aeration device 11 Air blowing part 11a Air-permeable material (Nonwoven fabric) 11b punching metal 11c air chamber 11d cover plate 12 supply source 13 piping 20 rotary feeder C coating layer

Continuation of the front page (72) Inventor Shinichi Igawa 2-10-26 Fujimi, Chiyoda-ku, Tokyo Maeda Construction Industry Co., Ltd. F term (reference) 4G035 AB44 AB54 AC14 AE13 AE17 AE19

Claims (4)

[Claims] 1. The granular material and water are agitated by drawing the granular material from the inlet of the granular material by the back pressure of the high-speed water flow running in the power tube and colliding with the inner surface of the cyclone at the tip of the power tube. A jet mixer for mixing to obtain a paste having a desired water / granule ratio is provided with a granule supply facility, the hopper for accommodating the granule, and a powder in the hopper. Including an aeration device that gives high fluidity to the granules, a supply amount adjusting device for the granules arranged at the outlet of the hopper, and a charging device that supplies the granules while dropping them toward the charging port A jet mixer, characterized in that: 2. An inner surface of the power tube and an inner surface portion in the vicinity of the powder material inlet are 0.1 μm in surface roughness.
The jet mixer according to claim 1, wherein the jet mixer is set as follows. 3. The jet mixer according to claim 1, wherein a coating layer having a surface roughness of 0.1 μm or less is applied to an inner surface of the power tube and an inner surface portion near the powder material inlet. . 4. A step of drawing the powder in the hopper from the inlet of the powder by the back pressure of the high-speed water flow running in the power tube, and causing the pulled powder to collide with the inner surface of the cyclone at the tip of the power tube. A powder mixing method for a jet mixer for obtaining a paste having a desired water / granule ratio by stirring and mixing the granules and water with each other. And a step of supplying the powder and granules with improved fluidity, and a step of dropping the granules with the increased fluidity toward the granule input port. Body supply method.