JPH0512017B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluid mixing device, and particularly to a mixing device suitable for mixing high viscosity fluids such as molten polymers.

[Conventional technology]

In general, fluid mixing devices include stirring blades, ribbons,
Although most mixing devices use a rotating body such as a screw to stir the fluid, there are also known mixing devices that do not use such a rotating body at all, one example of which is a static mixer. This static mixer consists of a plurality of elements in the shape of rectangular plates twisted approximately 180 degrees, which are arranged in series in a cylindrical tube, with phases shifted by 90 degrees from each other.
The fluid flowing inside the pipe is divided into two parts each time it passes through each element, and mixed by being twisted. Therefore, if n elements are used, the final number of fluid divisions (mixing ratio) S
is S=2 ⁿ , and by increasing the number of elements n, the mixing is dramatically improved.

[Problem to be solved by the invention]

However, with conventional static mixers,
Since the fluid is twisted using an element made of a rectangular plate twisted 180 degrees, the length of the element cannot be made very small, so if the number of elements is increased, the overall length becomes extremely long. . For example, in a static mixer, the ratio of the length L of the element to the inner diameter D of the pipe is usually
Since L/D is selected to be approximately 1.5, the pipe inner diameter D is
If it is 30mm, the total length is 90cm when the number of elements is n=20.
And, when the number of elements is n=30, the total length is
It also grows to 135cm.

The present invention aims to solve such problems, and is a static mixer-type mixing device that can dramatically increase the number of fluid divisions S and perform good mixing without increasing the overall length too much. The purpose is to provide

[Means to solve the problem]

The first invention of the present application, which was made to achieve the above object, has a plurality of flat mixing elements stacked in the passing direction of the fluid to be mixed, and each mixing element has a wire rod or a plate material curved in a wavy manner. The gist of the present invention is a mixing device characterized in that it is wound into a flat plate shape within a plane parallel to the curved direction.

Further, the second invention of the present application has a flat mixing element arranged to allow the fluid to be mixed to pass in the radial direction, and the mixing element is configured to move the wire or plate material curved in a wavy manner in the direction of the curvature. The gist of the mixing device is that it is wound into a flat plate in a plane perpendicular to the above.

Hereinafter, the present invention will be explained in more detail with reference to embodiments shown in the drawings.

〔Example〕

FIG. 1 is a schematic sectional view showing a mixing device according to an embodiment of the first invention of the present application. The mixing device, designated as a whole by the reference numeral 1, includes a plurality of flat mixing elements 3 arranged in a casing 2 in the direction of passage of fluids to be mixed.
It is made up of layers. This mixing element 3 is made by winding a wire or plate material (hereinafter simply referred to as a wire rod) 4 curved in a wavy manner as shown in FIG. When viewed from above, as shown in FIG. 3, numerous passages 5 are formed between adjacent wavy wire rods 4 passing through the mixing element 3 in the thickness direction. has been done. Therefore, a large number of small passages are formed over the entire surface of the mixing element 3, and the overall aperture ratio is large. The wire 4 used here may have a circular cross section, but
It is preferable to use a flat element as in the illustrated embodiment because the aperture ratio of the mixing element 3 can be increased. The material constituting the wire rod 4 is not particularly limited, and may be any metal, plastic, etc., but when particularly strong strength is required, it is preferable to use spring steel or the like.

The mixing element 3 is constructed by winding the wire 4 as described above, but simply winding the wire 4 may result in insufficient strength, inconvenience in handling, or inability to withstand fluid pressure. In that case, the contact portions of the adjacent wire rods 4 are connected by an appropriate method.
For example, it is preferable to join with adhesive, welding, brazing, sintering, etc. to increase the strength. In this case, although it is not necessary to bond all the contact portions in the mixing element 3, it is preferable to bond as many contact portions as possible. Moreover, as a joining method, sintering is preferable. If the wire 4 is wound into a plate shape and then sintered, a large number of contact parts can be joined, and the strength of the obtained mixing element 3 can be greatly increased. Furthermore, after sintering, as shown in the enlarged view in FIG. fill in the gaps. For this reason,
When the fluid is passed through this mixing element 3,
The minute gaps where fluid (particularly high viscosity fluid) tends to stagnate are eliminated, and local stagnation of fluid is prevented. This is a great advantage when the mixing element 3 is used with molten polymers where stagnation is a particular problem.

A large number of mixing elements 3 having the shape shown in FIG. 2 are stacked and housed in the casing 2 as shown in FIG. 1. At this time, mixing element 3
By randomly stacking the wire rods 4 of each mixing element 3, as shown in FIGS. 6 and 7,
Most of the wires 4 of the mixing elements 3 above and below are shifted from each other.

Next, a mixing operation by the mixing device 1 having the above configuration will be explained. In FIG. 1, fluids to be mixed flow into the casing 2 from an inlet 2A as indicated by arrows, pass through a large number of stacked mixing elements 3, and then flow out from a lower outlet 2B. Mixing is performed when this fluid passes through a large number of stacked mixing elements 3. That is, as shown in FIG. 7, the fluid that has passed through one passage 5 of the mixing element 3 at the top is divided into two by the wire rod 4 of the mixing element 3 below, and then divided into two by the wire rod 4 of the mixing element 3 below. In the mixing element 3, the fluids from the two passages 5 of the uppermost mixing element 3 flow into one passage 5 and are mixed, and then the fluid that has passed through that passage 5 is mixed by the wire of the mixing element 3 below. Then it is further divided into two parts. Thereafter, mixing and dividing of the fluids is repeated in the same manner, and eventually mixing is performed in the same manner as in a conventional static mixer.
Therefore, the number of divisions (mixing ratio) S after the fluid passes through the n stages of mixing elements 3 is S=2 ⁿ .

Here, the size of the passage 5 is determined as follows. That is, if the passage 5 is too small, the passage 5 may be crushed by the wires of the mixing elements 3 located above and below, which is not preferable.
On the other hand, if the passage 5 is too large, the fluids flowing in from the two passages 5 of the mixing element above it will not mix very well in one passage 5 of the mixing element, resulting in poor mixing efficiency. . Taking these points into consideration, the size of the passage 5 is selected.

Although the wire rod 4 of the mixing element 3 performs the function of dividing the fluid, it is not necessary to twist the fluid as in the element of a conventional static mixer.
Its width (thickness of the mixing element 3) does not need to be large, and can be extremely small as long as it has the necessary strength. Therefore, the thickness of the mixing element 3 formed of the wire rod 4 may be extremely thin, and therefore, the height of the mixing device in which the mixing elements 3 are stacked can be made extremely low. For example, a mixing element 3 using a flat wire 4 with a width of 2 mm and a thickness of 0.5 mm has a thickness of 2 mm, so even if the number n of mixing elements 3 is 30, the height of the stack of mixing elements 3 is: At only 6 cm, it is much shorter than conventional static mixers.
Moreover, as a result of the passage length of the fluid being shortened, fluid resistance is reduced, and pressure loss can be reduced by the mixing element 3. Furthermore, it is possible to stack a much larger number of mixing elements 3 than in conventional static mixers, and good mixing can be achieved.

Note that the mixing element 3 described above divides the fluid using a large number of wire rods 4, but if there are coagulates, aggregates, etc. in the fluid, the wire rods 4 cut these coagulates, aggregates, etc. However, in some cases it can be subdivided. In this case, it is preferable to use a thin, flat wire rod 4 for cutting aggregates, aggregates, etc. In addition, if there is a possibility that coagulates, aggregates, etc. cut by the wire rod 4 may meet and recombine after passing through the wire rod 4, it is recommended to increase the width of the wire rod 4 (thickness of the mixing element) to a certain extent. is effective.

In the present invention, it is preferable that the passages 5 formed in the mixing element 3 are as uniform as possible in order to allow the fluid to flow uniformly through the mixing element 3. by the way,
When the wavy wire 4 is simply wound, depending on the winding method, as shown in FIG. 8A, the vertices of the wires 4, 4 may contact each other to form a large passage 5, and as shown in FIG. 8B. As shown in FIG. 2, the wire rods 4 may overlap and there may be a portion where only a small passage 5 is formed between the wire rods. It is desirable to avoid the part of the structure shown in Fig. 8B as much as possible. Therefore, when winding the wire, in the part where the wires 4 and 4 may overlap, do not wind the wire too tightly, or do not wind the wire too tightly between the wires 4 and 4. Care must be taken, such as inserting an appropriate spacer.

Furthermore, to prevent the structure shown in FIG. 8B from occurring, it is also effective to make the waveform formed on the wire 4 uneven in pitch or height. When wire rods with non-uniform waveforms are wound, since the waveforms of adjacent wire rods are not the same, they will not overlap as shown in FIG. 8B. Further, the mixing element 3 is not limited to being made only from the wavy wire 4, but may be constructed by simultaneously winding the wavy wire 4 and the straight wire 7, as shown in FIG. Thus, the use of the wavy wire 4 and the straight wire 7 has the advantage that relatively uniform passages 5 can be formed throughout the mixing element.

In the embodiment shown in FIG. 1, a large number of the same mixing elements 3 are stacked.
are not necessarily the same, for example, the wavy size (pitch, pitch,
A configuration may also be adopted in which two types of mixing elements with different amplitudes, etc.) are alternately stacked. When different types of mixing elements are stacked, the wire rods of the upper and lower mixing elements rarely overlap, and therefore the fluid passing through the passage of one mixing element is reliably divided by the wire rods of the mixing element below it, resulting in a good flow. A mixture is performed. In this case, in order to prevent an increase in pressure loss, it is preferable to reduce the thickness of the wire forming the small waves.

Although the mixing device of the present invention can be used with any fluid, it is particularly preferred for mixing high viscosity fluids such as molten polymers. Further, the size of the mixing device of the present invention (i.e., the outer diameter of the mixing element 3 and the inner diameter of the casing 2) is not particularly limited, and may be designed as appropriate depending on the type of fluid used, the flow rate, etc., for example, about 10 mm. It is possible to have a diameter ranging from a small one to a large diameter of several meters. Further, the thickness, width, height of the corrugation, pitch, etc. of the wire used in the mixing element 3 may be appropriately determined depending on the type of fluid used, the outer diameter of the mixing element, etc. For example, when used for mixing molten polymers in the synthetic fiber manufacturing process, the outer diameter of the mixing element 3 is 20 to 50 mm.
Approximately mm is preferable. Also, mixing element outer diameter 50
For mm, the size of the wire 4 to be used is:
When using a flat one as shown,
The thickness should be about 0.2 to 1.0 mm and the width should be about 0.4 to 3.0 mm, but if you use one with a circular cross section, the diameter should be 0.2 to 1.0 mm.
degree is preferred. In addition, the waveform formed on the wire 4 has a wave height (height from valley to peak) of 0.4 to
2.0 mm and a pitch of about 0.5 to 2.0 are preferable. For a mixing element outer diameter of approximately 300 mm, the thickness of the wire 4 is 0.2 to 5.0 mm, the width is 0.4 to 20.0 mm, and the wave height is 0.4 to 5.0 mm.
10 mm, pitch is preferably about 0.5 to 20.0 mm. Of course, it goes without saying that values outside this range may be used.

In the embodiment shown in FIG.
The mixing device 1 is constructed by laminating a mixing element 3 made of a wavy wire in a casing 2 equipped with a casing 2B, but the shape of the casing 2 is not limited to this, and can be changed in various ways. A tube may also be used as a casing. That is, a mixing device can be constructed by stacking a large number of mixing elements 3 in a pipe. Furthermore, the mixing device of the present invention does not have to be composed only of the mixing element 3 made of a wavy wire, but can also be combined with other elements. Furthermore, it is also possible to incorporate it into other devices (for example, a filtration device, a cap pack, etc.).

These examples will be described below.

FIG. 10 shows an embodiment in which the present invention is combined with a conventional static mixer. The mixing device 11 of this embodiment has a plurality of mixing elements 13 and twisted blade-like elements 14 stacked in a casing 12 in the direction of passage of fluids to be mixed. The mixing element 13 used here has the same structure as the mixing element 3 used in the embodiment shown in FIG.
The fluid can be mixed by dividing it by the wire rods that constitute it. Further, the vane-shaped element 14 is similar to an element used in a conventional static mixer, and can twist the fluid passing therethrough by a large amount (180 degrees in the embodiment). By interposing this element 14, the fluid flowing within the casing 12 can be largely twisted to achieve lateral mixing. Thus, by mixing the mixing element 13 and the element 14, extremely good mixing can be achieved.

FIG. 11 shows an embodiment in which the mixing device of the present invention is incorporated into a spinneret pack in a melt spinning device. The cap pack, which is designated as a whole by reference numeral 21, includes a pack case 22, a cap plate 23,
A pressure support 24, a plurality of mixing elements 25 stacked on the pressure support 24, a filter medium 26 provided on the mixing element 25, and an adapter 2.
It is equipped with 7th class. The mixing element 25 is a first
A mixing element 3 similar to that used in the illustrated embodiment is used. Although the filter medium 26 is not particularly limited, it is usually a wire mesh 26.
a, sand 26b, sintered metal fiber filter 26c
Laminated bodies such as these are used. This cap pack 2
1, the molten polymer enters through the adapter 27;
After foreign substances are removed by the filter medium 26, the mixture is mixed while passing through the laminated mixing element 25, passed through the pressure support 24, and is spun out from the spinneret plate 23.
Therefore, since not only filtration but also mixing is performed within the cap pack 21, extremely high quality yarn can be manufactured. Furthermore, in this embodiment, the mixing element 25 is configured to support the sintered metal fiber filter 26c. Generally, the sintered metal fiber filter 26c has low strength, so if it is supported by a support plate with a large opening, the filter will deform at the opening and open, which is undesirable. Since the sintered metal fiber filter 26c is supported by the mixing element 25 having countless passages, the entire surface of the sintered metal fiber filter is supported relatively evenly, its deformation is prevented, and filtration defects can be prevented. It will be done.

FIG. 12 shows a base pack 21' which is a modification of the embodiment shown in FIG. This cap pack 2
1' has a configuration in which the pressure support body is omitted and the filter medium 26 is supported only by a large number of mixing elements 25. In this case, it goes without saying that the mixing element 25 has the strength to support the filter medium 26.

FIG. 13 shows an embodiment with a function for suppressing the velocity of fluid flowing through the center. This mixing device 31 has a casing 32 in which a large number of mixing elements 33 having a large opening formed in the center are stacked, and a cone member 34 is further arranged in the center. This mixing element 33 also has the same structure as the mixing element 33 described in the embodiment of FIG. 1, except that it has an opening in the center. The cone member 34 has a central structure with a closed upper end and an open lower end, and has a small through hole 35 on its outer periphery. In the mixing device 31 having this configuration, among the fluids flowing from above, those on the outer periphery pass through the mixing element 33 and are mixed. on the other hand,
The one in the center flows through the passage 36 between the central opening of the mixing element 33 and the outer surface of the cone member 34, and part of it flows inside the mixing element 33 (in the direction of the outer circumference) as shown by arrow a. It gradually flows, and a portion enters the inside of the cone member 34 and flows downward.
As a result, a portion of the fluid in the central portion is mixed with the fluid in the outer peripheral portion, and the flow velocity in the central portion is suppressed. Generally, the flow rate of fluid flowing inside a pipe or casing is faster in the center, but by providing this cone member 34, the flow rate in the center is suppressed and the flow rate is relatively uniform throughout the piston. Flow can be realized. Such a piston flow is highly favorable for molten polymers where thermal history has an important influence on quality.

Note that this embodiment allows the fluid in the center to gradually flow toward the outer periphery; however,
In order to ensure this flow in the outer circumferential direction, it is necessary to prevent the wires of vertically adjacent mixing elements 33 from overlapping as much as possible. For this purpose, it is preferable to make the heights of the corrugations of the wires forming adjacent mixing elements 33 different. Especially the 9th
As shown in the figure, when the mixing element 33 is composed of a wavy wire rod 4 and a straight wire rod 7, if the wire rods 7 overlap vertically, the flow of fluid in the radial direction will be blocked. When adjacent wire rods constitute the element 33, it is preferable that the heights of the waveforms of the wire rods are different and the positions of the straight wire rods 7 are shifted. It is also effective to incline the wire rods constituting the mixing element 33 so that the lower side is radially outward. The angle is 10~
30 degrees is preferred.

The combination of the mixing element 33 and the cone member 34 shown in FIG. 13 can be incorporated into the mixing device 11 shown in FIG.
It can be incorporated into the cap packs 21, 21' shown in FIG. In particular, it is preferable to incorporate it into a die pack because it can improve piston flow within the die pack and make the thermal history of the polymer spun from the die plate 23 uniform.

In addition, the mixing elements 3 and 1 explained above
No. 3, 25, 33, etc. have the effect of uniformly transmitting the temperature at the outer periphery to the center. Especially when it is sintered, the heat transfer effect increases. It is therefore also possible to use this mixing element as a heat conducting member.

FIG. 14 shows an embodiment of the second invention of the present application. The mixing device, designated as a whole by reference numeral 41, comprises:
A casing 42, a conduit 43 provided in the casing 42 and having a large number of through holes 43a on the outer peripheral surface, a flat mixing element 44 stacked on the outer periphery of the conduit 43, and arranged between each mixing element 44. The mixing element 44 includes a partition plate 45, an end plate 46 disposed on the uppermost mixing element 44, and a nut 47 for tightening and fixing the mixing element 44, the partition plate 45, the end plate 46, etc. Here, the outer diameter of the mixing element 44 is selected to be considerably smaller than the inner diameter of the casing 42, so that the fluid in the casing 42 flows into the mixing element 44 from the outer periphery of the mixing element 44, and the mixing element 44 and can flow radially inwardly into conduit 43 . As shown in FIG. 16, this mixing element 44 is made by winding a wave-curved wire or plate material (hereinafter simply referred to as wire material) 49 into a flat plate shape within a plane perpendicular to the curved direction to form a disk shape. It is composed of Therefore, when the partition plates 45 are arranged above and below the mixing element 44 and viewed from the outside in the radial direction, as shown in FIG. A large number of passages 50 communicating in the radial direction are formed, and
The position of the passage 50 is the wire rod 4 wound inside the passage 50.
It is out of line with the passage 9. In other words, the mixing element 44 is constructed by winding a wavy wire in many layers, but the radially adjacent wires 49, 49
The positions of the peaks and valleys of the wire rods 49 are shifted from each other. Therefore, as shown in FIG. 17, the passage 50 formed by the wire rods 49 located on one circumference is is starting to cross.

According to the mixing device 41 having the above configuration, the fluid to be mixed flows into the casing 42 from the opening 42A of the casing 42 as shown by the arrow, and flows from the outer periphery of each mixing element 44 into the mixing element 44.
radially inwardly and exits through central conduit 43. When the fluid flows through this mixing element 44, the fluid flows between each wire 49 as shown by the arrows in FIG. will be held.

Although a wire with a circular cross section may be used for the wire 49 used in this embodiment, it is preferable to use a flat wire as in the illustrated embodiment, since the aperture ratio of the mixing element can be increased. The material constituting the wire rod 49 is not particularly limited, and may be any metal, plastic, etc., but when particularly strong strength is required, it is preferable to use spring steel or the like. Moreover, if the wire rod 49 is simply wound,
If the strength is insufficient and it is inconvenient to handle, the contact portions of the adjacent wires 49 may be separated by an appropriate method.
For example, it is preferable to join with adhesive, welding, brazing, sintering, etc. to increase the strength. Further, in the above embodiment, partition plates 4 are provided above and below the mixing element 44.
Although the mixing elements 44 are stacked on both sides of the mixing elements 44, the partition plates 45 may be fixed in advance to the top and bottom or one side of the mixing elements 44 by an appropriate method, for example, by welding, brazing, etc.

Although the embodiments described above all used disc-shaped mixing elements, the mixing element used in the present invention is not necessarily circular, and may be a wire wound into a shape other than a circle, such as a rectangular shape. It may be hot.

〔Effect of the invention〕

As explained above, in the first invention of the present application, a plurality of mixing elements each formed by winding a wavy wire or plate into a flat plate are stacked in the fluid flow direction, so that the fluid flows through each mixing element. When passing through the mixer, division and merging are performed, and although it is much smaller than conventional static mixers, it can perform division and merging many times, resulting in extremely high mixing efficiency. have. Moreover, as a result of shortening the passage length of the fluid,
The pressure loss caused by fluid passage is small, making it extremely suitable for mixing high viscosity fluids such as molten polymers.

In addition, the second invention of the present application is configured to allow the fluid to pass in the radial direction through the mixing element formed by winding a wavy wire or plate material into a flat plate shape. When passing through wires or plates adjacent in the direction, splitting,
Even if the mixing element has a small diameter, the number of turns of the wire or plate material is large, so it is possible to perform division and merging many times, and although it is small, it has the effect of extremely high mixing efficiency. are doing. Moreover, since the passage length of the fluid can be shortened,
The pressure loss caused by fluid passage is small, making it extremely suitable for mixing high viscosity fluids such as molten polymers.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view showing a mixing device according to an embodiment of the first invention of the present application, Fig. 2 is a schematic perspective view of a mixing element used in the mixing device, and Fig. 3 is a partially enlarged view. A plan view, FIG. 4 is a schematic perspective view showing the wire rod used in the mixing element, FIG. 5 is a schematic plan view showing an enlarged part of the mixing element after sintering, and FIG. FIG. 7 is a schematic cross-sectional view showing a state in which fluid passes through multiple stages of mixing elements; FIGS. 8A and 8B are wire rods in the mixing elements, respectively. FIG. 9 is a schematic plan view illustrating a state of making a mixing element different from the above embodiment, and FIG. 10 is a schematic cross section showing another embodiment of the first invention of the present application. 11 and 12 are schematic sectional views showing an embodiment in which the first invention of the present application is applied to a cap pack, and FIG. 13 is a schematic sectional view of still another embodiment of the first invention of the present application, FIG. 14 is a schematic sectional view showing a mixing device according to an embodiment of the second invention of the present application, and FIG.
The figure is a side view of the mixing element and partition plate of the embodiment shown in Fig. 14, seen from the outer circumferential side, and Fig.
FIG. 17 is a perspective view schematically showing a mixing element used in the illustrated embodiment, and FIG. 17 is a sectional view taken along the line A-A in FIG. 14. DESCRIPTION OF SYMBOLS 1... Mixing device, 2... Casing, 3... Mixing element, 4... Wire rod, 5... Passage, 11...
...Mixing device, 12...Casing, 13...Mixing element, 14...Blade-shaped element, 21
...Base pack, 22...Base case, 23...
Mouth plate, 24... Pressure support, 25... Mixing element, 26... Filter medium, 27... Adapter, 41... Mixing device, 42... Casing, 4
3... Conduit, 44... Mixing element, 45...
Partition plate, 49... wire rod, 50... passage.

Claims (1)

[Scope of Claims] 1. A device having a plurality of flat mixing elements stacked in the direction of passage of fluids to be mixed, each of which mixes a wavy curved wire or plate within a plane parallel to the curved direction. A mixing device characterized in that it is configured by being rolled into a flat plate. 2. It has a flat mixing element arranged to allow the fluid to be mixed to pass in the radial direction, and the mixing element converts a wavy curved wire or plate into a flat plate in a plane perpendicular to the direction of the curvature. A mixing device characterized by being configured by being rolled into a shape.