JP2003340253A5 - - Google Patents

Description

Detailed Description of the Invention
[0001]
Field of the Invention
According to the present invention, when mixing powder with a liquid, in particular when the liquid is a solvent, the powder is prevented from becoming an undissolved substance such as “dama” or “mako”, and the powder is added to the liquid. The present invention relates to an apparatus and method for mixing powder and liquid which can be uniformly and continuously mixed.
[0002]
[Prior Art]
Conventionally, the powder is continuously mixed with the liquid, but particularly when the liquid is a solvent, so-called powder lumps dissolve only in the periphery and the liquid does not penetrate to the inside, so-called Undissolved matter such as "dama" and "makko" was generated, and the powder could not be uniformly mixed with the liquid. For this reason, the mixing accuracy is not always constant due to the undissolved matter, which causes various problems. Various methods and devices have been proposed to solve this.
[0003]
As means for continuously mixing powder and liquid, Japanese Patent Application Laid-Open No. 61-238329 discloses a "polymer dissolution method". As shown in FIG. 4, in this dissolution method, the solid polymer 20 in the particulate state is allowed to freely fall from the container 21, and a jet water flow 22 intersecting the free fall direction is disposed below the container 21. The jet flow of the solid polymer 20 trapped on the inclined plate 24 disposed in the vessel 25 containing the mixed solution 23 and the solid polymer 20 as well as capturing the solid polymer 20 falling from the vessel 21 by the jet stream 22 22 make them collide, thereby mixing the solid polymer 20 with water, preventing the generation of "slugging".
[0004]
However, in this “solution method of polymer”, in order to capture the falling solid polymer, a large amount of water of the jet water stream must be used, and therefore, only low concentration mixing can be performed. The In addition, due to the collision between the jet flow and the inclined plate, there is a risk that the water droplets scatter around and the scattered water droplets or mist leak to the outside.
[0005]
JP-A-8-283418 discloses "a method of dissolving water-soluble polymer powder". In this dissolution method, a high-speed rotor for stirring is provided in the dissolution vessel, and while stirring the solvent by rotating the high-speed rotor, a predetermined amount of water-soluble polymer powder is charged in a short time, After completion of the addition, the temperature is raised to dissolve the water-soluble polymer powder.
[0006]
In this method, after dissolving a predetermined amount of the water-soluble polymer powder, it is necessary to dissolve the predetermined amount of the water-soluble polymer powder again, and the water-soluble polymer powder can be dissolved continuously. It was not.
[0007]
Japanese Patent Application Laid-Open No. 7-22918 discloses "Method and apparatus for mixing liquid and other substances". As shown in FIG. 5, in this mixing method and apparatus, a rotary plate 31 rotating in a horizontal plane is provided in the mixing container 30 which can be put into a vacuum state, and the inside of the mixing container 30 is evacuated by the vacuum pump 32 The liquid is supplied to the vicinity of the rotation center of the rotary plate 31 by a liquid supply pipe 33, and the liquid is developed into a thin film by the centrifugal force of the rotary plate 31. The powder 35 from the hopper 34 is gradually dropped and spread on the liquid developed in the same thin film state, and due to the difference in centrifugal force acting on the liquid and the powder, mutual cutting called slip cutting is performed. Mixing is performed while causing a gap. In addition, a retention ring 36 is provided on the outer peripheral side of the rotary plate to forcibly receive the mixture of liquid and powder projected in the centrifugal direction, and the mixture is dropped from the residence ring 36 into the mixing container. There is.
[0008]
In this method and apparatus, when the rotational speed of the rotating plate is increased too much, the liquid can not spread in a thin film, and conversely, the liquid or powder may be scattered due to the drop on the rotating plate. In addition, equipment for evacuating the inside of the mixing container is required, and a member such as a motor for rotationally driving the rotary plate and a retaining ring are required, and the size of the apparatus has to be increased.
[0009]
Further, as shown in FIG. 6, the liquid 42 is caused to flow out in a spiral along the inner peripheral surface of the funnel-shaped mixing device 40, and the powder 41 is dropped onto the liquid 42 to form powder 41 and liquid 42.
An apparatus for mixing and is also used. At this time, by reducing the solubility of the liquid, the occurrence of "dama" or "maruko" is prevented. For this reason, an apparatus for cooling the temperature of the liquid was required. Also, in order to reduce the solubility of the liquid, it is necessary for the powder and the liquid to be in contact with each other in order to allow the liquid to penetrate into the lump of the powder. Had to be longer.
[0010]
Japanese Patent Application Laid-Open No. 2000-328346 to the applicant of the present application discloses "a method of preparing a stock solution for spinning acrylonitrile-based polymer". This adjustment method is
In this adjustment method, powdery acrylonitrile-based polymer and liquid that is a solvent are continuously mixed in a mixing chamber to form a chiller, and as shown in FIG. 7, the polymer input formed in the upper part of the mixing chamber 45 While constantly wetting the inner wall surface 48 of the port 46 with liquid, the polymer is dropped from the polymer inlet 46 and supplied, and a large number of small diameter nozzles 47 formed on the peripheral wall of the mixing chamber 45 provide at least two directions or more. The liquid is injected into the mixing chamber from the direction of (1) to continuously mix the polymer and the liquid.
[0011]
In this adjustment method, polymer fine powder that has been blown up when supplied from the polymer inlet 46 adheres to the inner wall surface 48 of the inlet, and a liquid, which is a solvent that is evaporated or scattered, adheres to the adhered polymer fine powder, and "dummy" The generation of clumps of water is prevented by making the inner wall surface 48 of the inlet port a wetted wall. In addition, since the liquid sprayed from the small-diameter nozzle 47 does not concentrate on one point (central point) and is dispersed and sprayed in multiple directions, the liquids are prevented from colliding and scattering. It is possible,
It is possible to effectively disperse the polymer.
[0012]
However, in the configuration as the mixing device disclosed in this publication, the upper portion of the mixing chamber 45 is an open polymer inlet 46, and the polymer is directly supplied from the transport device provided above the polymer inlet 46. It is configured to be introduced into the mixing chamber 45. For this reason, in the configuration of this mixing apparatus, the polymer introduced into the mixing chamber soars, and the polymer is scattered to the outside of the mixing chamber, and the polymer dropped after being introduced is difficult to be concentratedly supplied to the central region of the mixing chamber The mixing with the liquid jetted from the nozzle is difficult to be performed uniformly.
[0013]
[Problems to be solved by the invention]
The present invention is an improvement of the technology disclosed in the above-mentioned Japanese Patent Laid-Open No. 2000-328346, and prevents the generation of "dama" and "mako" when mixing powder and liquid, and can be uniformly mixed, and An object of the present invention is to provide a mixing device and a mixing method capable of continuously performing mixing at a desired concentration.
[0014]
[Means for Solving the Problems]
The objects of the present invention are achieved by the inventions described in claims 1 to 4 of the present application.
That is, the invention according to claim 1 of the present application is a cylindrical container having an axial center directed in the vertical direction, a closed portion at the upper end, and an outlet at the lower end, and a circumferential surface along the circumferential direction of the cylindrical container. And a plurality of jet holes directed to the inner space of the cylindrical container, liquid supply parts connected to the respective jet holes, and a lower part concentric with the axis of the cylindrical container in the cylindrical container. has an opening, in the mixing device of the powder and the liquid, characterized in that it comprises a conduit and to continuously quantify free fall the powder from the lower opening located above the site of the injection holes .
[0015]
In the present invention, the liquid supplied from the liquid supply portion can be jetted toward the inside of the cylindrical container from the plurality of jet holes provided in the circumferential direction of the cylindrical container, and provided at the upper portion of the jet hole. From the lower opening of the conduit, the powder can be continuously dropped freely to the place where the liquid is jetted.
For this reason, the powder which has been continuously free to be quantified from the pipe continuously falls into the central region of the cylindrical container and collides with the liquid which has become the jet flow, and the powder is continuously mixed by the liquid. Will be able to Even if the powder falls free from the pipeline in the form of lumps, the lumps are broken up by the jet flow from each direction and generate insoluble matter such as “balls” and “marcoles” and undispersed lumps. The powder can be uniformly mixed with the liquid without mixing. The shape of the conduit is not limited to a cylindrical shape, and the cross-sectional shape can be a semicircular shape, a polygonal shape, a rectangular shape, or the like. Moreover, it can also be set as the structure where a cross-sectional shape changes along the longitudinal direction of a conduit. However, the cross-sectional shape of the lower opening of the conduit needs to be circular.
[0016]
The continuous fixed amount drop from the pipe is established by installing a conveying means such as a screw conveyor in the communication path connected to the pipe and supplying the powder to the pipe continuously by the fixed amount by the conveying means. It can be carried out. Moreover, it can carry out by installing a well-known continuous fixed quantity supply mechanism in the lower end part of a pipe line. In addition to the screw conveyor, it is also possible to use a conveying means capable of continuously feeding powder. Also,
By also opening the upper side of the pipeline, the flow of air in the pipeline flows from the upper opening to the lower opening, and the powder supplied into the pipeline is discharged from the upper side of the pipeline. It will be discharged from the lower opening by the air flow from the opening. Even if the powder supplied into the pipe is partially scattered from the opening at the upper side of the pipe, since the closed portion is provided at the upper end of the cylindrical container, the scattered powder leaks to the outside of the cylindrical container It is surely prevented from coming out.
[0017]
By adjusting the amount of liquid to be jetted and the amount of powder to be freely dropped continuously, it is possible to produce a mixed solution of a desired concentration. Furthermore, the continuously mixed liquid mixture can be continuously delivered from the outlet of the cylindrical container to the processing apparatus of the next step.
The direction of the jet flow from the jet holes is preferably horizontal or downward from the horizontal direction.
[0018]
In the apparatus for mixing powder and liquid according to the present invention, the large-diameter upper cylindrical portion covering the pipeline, the small-diameter lower cylindrical portion in which the jet holes are disposed, and the upper cylindrical portion and the lower cylindrical portion are connected A connecting portion having an inclined surface, and a plurality of slits formed in the vicinity of a connecting portion between the connecting portion and the lower cylindrical portion and connected to the liquid supply portion ; Preferably, the diameter is larger than the inner diameter of the lower opening .
[0019]
In the present invention, the shape of the cylindrical container is limited, and a plurality of slits are provided in the vicinity of the connection portion between the connection portion and the lower cylindrical portion, and the liquid from the liquid supply portion flows out from the slit. The inner wall of can be a wetted wall. When the inner wall of the lower cylindrical portion is a wetted wall, the powder adhering to the lower cylindrical portion can be washed away with the liquid. The slit may have a shape having a predetermined length in the circumferential direction of the lower cylindrical portion, and may be configured by arranging the slits in a plurality of circumferential directions, or the connection portion along the circumferential direction of a large number of small holes. It can also be configured by being provided in the vicinity. Also,
A gap can be formed between the lower end portion of the connecting portion and the upper end portion of the lower cylindrical portion so that the liquid can flow out from the gap. The slits may be provided near the upper end of the lower cylindrical portion, near the lower end of the connecting portion, or both.
[0020]
Although the term "slit" is used in the present invention, the slit used here is not limited to an opening having a predetermined width and a predetermined length, and the lower cylindrical portion is a wetted wall as described above. For this purpose, all the openings through which the liquid can be flushed out are used. In addition, the liquid flowing down to form a wetted wall is sufficient if the lower cylindrical portion is sufficiently wetted, and it is not particularly necessary to perform excessive liquid downflow.
[0021]
The mixing apparatus for powder and liquid according to the present invention can be provided with a plurality of upper slits formed in the circumferential direction near the upper end of the upper cylindrical part and connected to the liquid supply part .
[0022]
The invention according to claim 2 of the present application is, in addition to the subject matter of claim 1, an apparatus for mixing powder and liquid in which the matter in which the injection holes are disposed in such a direction that the jet streams from the plural injection holes do not interfere with each other It is in.
[0023]
In the present invention, since the injection streams injected from the respective ejection holes do not interfere with each other, the injection streams are prevented from colliding with each other to prevent the generation of the fog and the collision of the injection streams and scattering. Can. As injection in a state where they do not interfere with each other, each injection flow may be mutually interfered with each other, such as injecting each injection flow in a three-dimensional twisted state, or injecting separately in the vertical direction. If it does not exist, it can be injected in an appropriate direction.
[0024]
In addition, it is desirable that the powder which falls freely from the pipeline falls into the area which can be formed by the jet flow from each jet hole, and as the direction of jet flow from the jet hole, from horizontal direction or horizontal direction It is desirable that it is directed downward.
[0025]
In the invention according to claim 3 of the present invention, the powder is allowed to fall continuously and continuously from above into the central region of the cylindrical container whose axis is directed in the vertical direction, and the cylinder in the intermediate region of the powder is dropped A method of mixing powder and liquid is characterized in that a plurality of jetted liquids are simultaneously jetted from a plurality of jet holes on the circumferential surface of the cylindrical vessel in the axial direction of the cylindrical vessel.
In the present invention, the liquid is simultaneously jetted from the plurality of ejection holes in the cylindrical container, and the powder is continuously dropped freely from the upper side of the cylindrical container to the area where the jetted liquid is concentrated. A mixed solution of concentration can be produced continuously and uniformly. Moreover, even if the powder falls as a lump, the lump is broken by the jet flow, and the uniform mixed liquid is continuously produced without generating an undissolved substance such as so-called "dama" or "makko". Will be able to manufacture.
[0026]
The invention according to claim 4 of the present application is, in addition to the subject matter of claim 3, a method of mixing powder and liquid in which the matter formed by injecting the liquid in the direction in which the jet streams of the jetted liquid do not interfere with each other is limited.
[0027]
In the present invention, by injecting the jet streams jetted from the respective jet holes in a state where they do not interfere with each other, the powders are mixed in a state in which the jet streams collide with each other to prevent the mist generation and the liquid scattering. Will be able to As injection in a state where they do not interfere with each other, injection may be performed such that each injection flow is twisted in a three-dimensional manner, or injection may be mutually interfered with each other, such as injecting separately in the vertical direction. If it does not exist, it can be performed by injecting it in an appropriate direction.
[0028]
In addition, it is desirable to make the powder which falls freely from the pipeline fall in the area which can be formed by the jet flow from each jet hole, and the direction of jet flow from the jet hole may be horizontal direction It is desirable to face downward from the horizontal direction.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be specifically described based on the attached drawings.
FIG. 1 shows the diagram of the embodiment of the present application. A fixed amount of powder 10 is continuously transported by the screw conveyor 8 in the supply pipe 6 with respect to the powder 10 input from the powder input port 7. The screw conveyor 8 can control the transport amount of the powder 10 by controlling the number of rotations of the drive motor 9 whose rotation is controlled by a controller (not shown).
The conveyance means for continuously supplying the powder 10 in a fixed amount in the supply pipe 6 is not limited to the screw conveyor, and an existing conveyance means such as a belt conveyor, a push conveyor, an air conveyor, etc. can be used. In addition, as means for continuously performing free fall in a fixed amount, fixed amount supply means such as a rotary valve can be installed at the lower end portion of the conduit 5.
[0030]
The powder 10 discharged from the supply pipe 6 is supplied into the pipe 5 and freely falls into the cylindrical container 1 from the lower opening 5 a concentrically arranged with the axis of the cylindrical container 1. Also,
By opening the upper side of the conduit 5 as well, the flow of air in the conduit 5 flows from the upper opening toward the lower opening, and the powder supplied into the conduit is discharged from the conduit. It is discharged from the lower opening 5a by the air flow from the one opening. Even if the powder supplied into the pipe is partially scattered from the opening at the upper side of the pipe, since the closed portion 16 is provided at the upper end of the cylindrical container 1, the scattered powder is not Leakage to the outside is surely prevented.
[0031]
A portion of the outer peripheral surface of the lower cylindrical portion 4 of the cylindrical container 1 is covered by the liquid supply portion 11;
A liquid supplied from a supply path (not shown) is supplied into the liquid supply unit 11. Also,
A jet hole 1 is formed on the circumferential surface of the lower cylindrical portion 4 covered by the liquid supply portion 11.
2 is provided, and the liquid from the liquid supply portion 11 is jetted so that it becomes the jet flow 12a from the jet holes and becomes tangential in a virtual circle concentric with the center of the lower cylindrical portion 4 as shown in FIG. It is done. The respective injection streams 12 a are injected so as to pass vertically away from each other in the axial direction of the lower circular head 4 so as not to interfere with each other. Radius of the imaginary circle, Kona径the mixed powder 10, the installed number of ejection holes can be appropriately selected depending on the inside diameter or the like of the ejection holes 12. By making the jet streams not interfere with each other,
It is possible to prevent the generation of mist due to the collision of the jet flow and the scattering of the liquid. In particular, when the liquid is scattered, the liquid adheres to the lower end of the conduit 5 and the powder 10 may be solidified at the lower end of the conduit 5, but the jet streams do not interfere with each other by doing,
Such a situation can be prevented.
[0032]
In addition, although the injection direction of each injection flow 12a is prescribed | regulated so that each injection flow 12a may not mutually interfere, suitable injection flows can also be made to collide. In the present invention, it is naturally included to cause the jet streams to collide with each other. In this case, to prevent the mist generated by the collision of the jet flow and the scattering liquid from adhering to the conduit 5,
It is necessary to make the lower end position of the conduit 5 higher than the collision position of the injection flow.
[0033]
The jetting direction of each jet stream 12a is preferably jetted downward from the horizontal direction. However, in the present invention, the jet stream may not be jetted in the horizontal direction or upward. Naturally, the ejection direction of each injection stream 12a is an arbitrary direction.
[0034]
The liquid in the liquid supply unit 11 can be made to flow out of the slit 13 provided in the vicinity of the joint portion between the connection portion 3 and the lower cylindrical portion 4. By the outflow from the slit 13,
The inner wall surface of the lower cylindrical portion 4 can be a wetted wall. The slit 13 may be configured by arranging an elongated opening shape in a large number of circumferential directions, or by arranging a large number of small holes in a plurality of rows in the circumferential direction, or the lower end portion of the connecting portion 3 The outer diameter of the lower cylindrical portion 4 is smaller than the inner diameter of the lower cylindrical portion 4 and a part of the lower end portion is inserted into the lower cylindrical portion 4 to form a gap between the lower end portion and the upper end of the lower cylindrical portion 4 It can also be configured. The point is that if the inner wall surface of the lower cylindrical portion 4 can be made into a wetted wall by the liquid flowing out of the slit 13, that shape can be used.
[0035]
Further, as shown in FIG. 2, the liquid supply portion 11 is also configured to cover the upper end portion of the upper cylindrical portion 2, and the upper slit 14 is formed in the portion of the upper circular head 2 covered by the liquid supply portion 11. The inner wall surface of the upper cylindrical portion 2, the inner wall surface of the connecting portion, and the inner wall surface of the lower cylindrical portion 4 can also be used as a wetted wall by letting the liquid flow out from the upper slit 14.
[0036]
The upper slit 14 may be configured by arranging an elongated opening shape in a large number of circumferential directions, or by arranging a large number of small holes in a plurality of rows in a circumferential direction, or the upper head A gap may be formed between the portion 2 and the blocking portion 16. Alternatively, the liquid supply unit 11 may be divided into a liquid supply unit that covers the upper slit and a liquid supply unit that covers the lower cylindrical unit.
[0037]
Next, the mixing action of the powder 10 and the liquid will be described. The powder 10 supplied from a hopper or the like (not shown) is continuously transported by a fixed amount by the screw conveyor 8 in the supply pipe 6. The powder 10 discharged from the end of the supply pipe 6 is guided by the pipe 5 and freely falls into the central region of the axial center of the cylindrical container 1. During free fall, the powder 10 collides with the jet flow of the liquid ejected from the plurality of ejection holes provided in the lower cylindrical portion 4 and is uniformly mixed. At this time, since the jet flow passes vertically and horizontally in the drop region as shown in FIG. 3, even if there is a lump or the like in the powder 10, the lump can be broken by the jet flow, and the powder 10 and the liquid can be uniformly mixed.
[0038]
Further, the powder 10 adhering to the inner wall surface of the lower cylindrical portion 4 in the middle of falling is a slit 1
3 or the liquid flowing out of the upper slit 14 can be washed away and supplied from the outlet 117 to the external member together with the liquid mixture. According to the present invention, powder and liquid as liquid can be continuously mixed at a constant concentration. Even if clumps are mixed with the falling powder, the clumps are broken up by the jet flow, and the generation of undissolved matter such as “dama” or “makko” can be efficiently prevented.
[0039]
Next, the present invention will be described more specifically using examples.
〔Example〕
The polymer powder for acrylic fiber is allowed to fall freely from the pipeline 5 at 50 kg / min,
Injection of dimethylacetamide at 35 ° C at 200 kg / min from the injection hole 12,
Mixed. In the resulting slurry, no "makko" was present.
[0040]
Comparative Example
The polymer powder for acrylic fiber and dimethylacetamide were mixed under the same conditions as in the example using a mixing device in the form of a rod shown in FIG. In the slurry obtained at this time, “margin” of 10 pieces / min was generated.

Claims (4)

A cylindrical container having an axis directed vertically and having a closed portion at the upper end and an outlet at the lower end;
A plurality of ejection holes disposed on the circumferential surface of the cylindrical container along the circumferential direction and facing the inner space of the cylindrical container,
A liquid supply unit connected to each of the ejection holes;
A tube having a lower opening coaxial with the axial center of the cylindrical container in the cylindrical container, and a tube for continuously dropping free amount of powder from the lower opening located at the upper part of the ejection hole Road,
An apparatus for mixing powder and liquid, comprising: The mixing device for powder and liquid according to claim 1, wherein the jet holes are disposed in a direction in which the jet streams from the plurality of jet holes do not interfere with each other. The powder is allowed to fall continuously and quantitatively from above onto the central region of the cylindrical container whose axis is directed vertically.
In the midway region of the falling of the powder, it is simultaneously jetted in the axial center direction of the cylindrical container from a plurality of ejection holes on the peripheral surface of the cylindrical container,
A method of mixing powder and liquid characterized by The method for mixing powder and liquid according to claim 3, wherein the liquid is injected in a direction in which the jet streams of the jet liquid do not interfere with each other.