JPH0738941B2 - Slurry preparation method and apparatus therefor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method and an apparatus for mixing powder and liquid to prepare a uniform slurry.

(Prior art and its problems) Mixing powder and liquid is not limited to general chemical industry, but also civil engineering.
It is also a necessary means for kneading cement mortar and other materials in the field of construction.

In such solid-liquid mixing, in addition to obtaining homogeneity of the mixture, that is, slurry, the time required for mixing may be limited in order to avoid undesirable phenomena such as coagulation or mixing of bubbles during kneading. Is required to be shortened.

Thus, the conventional mixing is usually performed in a mechanical mixing device, and the secondary particle dispersion is performed relatively efficiently, but the efficiency is poor in the process from the secondary particle dispersion to the primary particle dispersion. Power and time are required, which is not preferable.

(Object of the Invention) An object of the present invention is to shorten the residence time of a mixture in a mixing apparatus and continuously prepare and discharge a homogeneous slurry.

(Structure of the Invention) In the present invention, the mechanical mixing device includes a known mixing device of driving type and non-driving type in a continuous type device, and the flow of the mixture in the device (that is, up to the discharge end). Transfer path In particular, a device having a tubular transfer path.

According to the present invention, ultrasonic transducers are arranged on the outer wall of a tubular transfer passage (pipe passage) of the above device so as to face or appropriately,
By vibrating at 00Hz ~ 400,000Hz, the fluidized mixture in the secondary particle dispersion state can be delivered to the predetermined target place as the primary particle dispersion state during the stirring or transfer, and the homogeneous slurry can be obtained in a short time. It can be continuously prepared.

The ultrasonic vibrator applied to the present invention is nickel, permalloy or the like in the case of the magnetostrictive type, and quartz, barium titanate or the like can be used in the piezoelectric type. Further, the mounting position may be an arbitrary position in the pipeline, and the mounting position may be plural. When a plurality of vibrators are installed, the frequency and output of each vibrator can be made different.

It is more efficient to use the ultrasonic waves generated from the vibrator by focusing them, and the output thereof is appropriately selected in balance with the mixing ability of the device.

In the present invention, the particles of the secondary particle-dispersed mixture in the transfer conduit are themselves vibrated by ultrasonic vibration and easily become the primary particle dispersed state, which results in the efficiency of the device which was conventionally inefficient. Can be improved.

Furthermore, since the present invention can be applied without modifying the conventional mixing device, the conventional device is economical and can be used.

(Application Example of the Invention) The present invention can be used for preparing various slurries as described above, but exerts a remarkable effect when applied to the self-leveling construction which requires a short time dispersion.

Therefore, a method for preparing a self-leveling material having high fluidity and a mixing apparatus for the same will be described below.

In order to perform self-leveling construction with high quality and high accuracy, a slurry having both high fluidity, self-smoothness and material separation resistance must be prepared, but conditions in which high fluidity of slurry and material separation resistance are contradictory Is. Thickeners, dispersants, etc. are added to impart these properties, but it generally takes a lot of time to uniformly disperse them with the hydraulic material and the filler as the main materials. is there.

Even in the above-mentioned ordinary mechanical mixing device, it is difficult to obtain a desired slurry in a short time because the fluidity is insufficient and the powder or the partial agglomeration occurs in about 20 seconds.

In order to overcome this, the size of the device must be extremely increased and the slurry supply amount must be significantly limited.

According to the present invention, a good slurry of the self-leveling material can be obtained in a short time and the construction period can be shortened.

Although the above description has been made for a continuous mixing apparatus, the method of the present invention can be applied to a batch type apparatus and the same effect can be obtained.

(Explanation of Device) A typical configuration example of the device of the present invention is as shown in FIG. 1 to FIG. 3, in which (1) is a powder loading hopper and (2) is a circular tube connected to it. The central rotating shaft (4) directly connected to the drive source (3) is equipped with a screw (5) and a stirring blade (6). (7) is a liquid supply pipe.

The powder is agitated and transferred by the screw (5), mixed with the liquid supply, and mixed by the agitating blade (6) to be in a secondary particle dispersed state.

This fluid receives ultrasonic vibration from an ultrasonic transducer (10) provided between the discharge side of the mixing cylinder or the pipe (8) and the discharge port (9), and the particles themselves It vibrates and becomes a primary particle dispersed state during transfer. The ultrasonic transducer (10) is fixed to the outer circumference of the pipe wall so as to face the ultrasonic wave, and the ultrasonic source (11)
Driven by. As a result of the experiment, the effective frequency is 1
5,000 Hz or higher.

FIG. 3 shows an example of a non-driving type mixer, in which the central shaft (4a) and the screw blades (5a) are fixed in the body.

(Example) Using the apparatus of FIG. 1 and using a cement-based self-leveling material "DENKA SL" manufactured by Denki Kagaku Kogyo Co., Ltd., a cement slurry having a particle size of about 1,500 cps after mixing was subjected to the following conditions. With a capacity of about 30 l / min.

Capacity of stirrer / mixer: 2l Shaft speed: 400rpm Drive output: 3.7kw Stirrer / mixer transit time: 4 seconds Ultrasonic vibrating part (pipe) capacity: 5l Ultrasonic output: 0.5kw Transducer: 20,000Hz Vibration application time The slurry obtained for 10 seconds was as shown in the table below.

When the slurry obtained in the above example was applied to a rough 3 m × 3 m (9 m ² ) concrete substrate with a thickness of about 10 mm, a good horizontal floor substrate was obtained.

In the above table, Comparative Example (1) is a slurry property at the same water ratio when ultrasonic vibration is not applied in the apparatus of the Example, and Comparative Example (2) is a water ratio for obtaining the same flow. The present invention relates to the slurry properties when the value is increased.

Furthermore, when it is desired to obtain a slurry having the same properties as those of the above embodiment with the same capacity using only a conventional mixing device, the capacity of the mixing section is
It is obvious that it is extremely uneconomical and inefficient because the driving force must be 60 liters and the driving force must be 5.5 kw.

Therefore, according to the present invention, the driving output can be reduced, the driving unit can be downsized, and a good slurry can be prepared in a short time.

[Brief description of drawings]

1 to 3 are schematic configuration diagrams of an apparatus according to an embodiment of the present invention. (5) …… Screw, (6) …… Fragile wings (8) …… Pipe, (10) …… Ultrasonic transducer

Continuation of the front page (56) References JP-A 61-21723 (JP, A) JP-A 59-142289 (JP, A) JP-A 60-48826 (JP, A) JP-B 58-37003 (JP , B2) JP-B 53-13452 (JP, B2) JP-B 61-6092 (JP, Y2)

Claims (3)

[Claims] 1. A powder is brought into contact with a liquid during stirring transfer or at the time of stirring to mix the powder into a secondary particle dispersed state, and then ultrasonic vibration is applied in a transfer path of the mixed fluid to give a primary particle dispersed state. A method for preparing a slurry, comprising: 2. The method for preparing a slurry according to claim 1, wherein the powder is a raw material composition of a self-leveling material. 3. A tubular mixing and stirring device comprising a powder feeding part at one end and a stirring screw and mixing means in a pipeline having a discharge port at the other end, and a discharge port of the tubular mixing and stirring device. Slurry preparing device in which an ultrasonic transducer is arranged on the outer circumference of the side tube wall.