JP2009247969A - Stirring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stirring apparatus having good mixing characteristic even in the case of mixing two or more kinds of treatment materials with different viscosities. <P>SOLUTION: The stirring apparatus includes a plurality of stirring blades 7, ... arranged discontinuously helically along the inner wall of a stirring tank 1 and respectively attached to a stirring shaft 2 through support arms 6 and a plurality of baffles 9, ... extended out the inner wall of the stirring tank 1 at positions where the baffles do not cause interference with the stirring blades 7, ... respective attached to support arms 8, and installed in more center side than the stirring blades 7 and the width W<SB>1</SB>of the stirring blades 7, ... in the radius direction of the stirring tank 1 is set in a range of 10 to 20% of the inner diameter (diameter) of the stirring tank 1 and the clearance C<SB>1</SB>between the stirring blades 7 in the radius direction of the stirring tank 1 and the inner wall of the stirring tank 1 and the clearance C<SB>2</SB>between the stirring blades 7 in the radius direction of the stirring tank 1 and the baffles 9 are set respectively in a range of 3% or less of the inner diameter (diameter) of the stirring tank 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an agitation device for agitation processing not only in the chemical field but also for the purpose of mixing in the chemical, food, metal mining, and material industries in general. It is also useful for mixing stirred products. The mixing of the agitated material is not limited to the mixing of liquids, but a mixture of solids (or powders) and liquids, mixing of solids (or powders), mixing of liquids in an aerated state, etc. including.

  It is said that a helical ribbon blade (especially a double helical ribbon blade) having good stirring characteristics in the vertical direction of the stirring tank is suitable as a stirring device for stirring processing for the purpose of mixing a high viscosity stirring processed product. (Patent Documents 1 to 3).

  This type of stirring device is rotationally driven in the direction in which the discharge force acts on the upper surface of the helical ribbon blade, that is, rotationally driven so that the feeding direction of the helical ribbon blade is upward (hereinafter referred to as “scraping rotation”). After the agitated processed material is sucked in from the upper side on the center side and sent from the center side to the outer peripheral side along the bottom of the stirring tank, and then sent upward along the inner wall of the stirring tank Mixing is performed by generating a series of circulating flows that are sucked to the center side near the surface of the stirred product, descended downward, and sucked again.

  On the other hand, if rotational driving is performed in the direction in which the discharge force is applied on the lower surface of the helical ribbon blade, that is, rotational driving so that the feeding direction of the helical ribbon blade is downward (hereinafter referred to as “scraping rotation”), The stirred product is sucked in from the lower side on the center side, sent from the center side to the outer peripheral side near the surface of the stirred product, and sent downward along the inner wall of the stirred tank, and then to the bottom of the stirred tank Mixing can also be performed by generating a series of circulating flows that are sucked in along the center and raised upward and sucked again.

  However, with the helical ribbon blade alone, there is a fixed point where the flow of the agitated product does not occur on the center side of the blade, and the mixing as a whole may not be sufficiently performed. A plurality of stirring blades that are intermittently arranged in a helical shape and are each attached to a stirring shaft via a support arm, and are attached to each support arm that extends from the inner wall of the stirring tank at a position that does not interfere with the stirring blade. A stirring device including a plurality of baffles disposed closer to the center than the stirring blade has been proposed (Patent Document 4).

Japanese Patent No. 2649131 JP 2000-317292 A Japanese Patent Laid-Open No. 8-266881 Japanese Patent Publication No. 5-59782

  By the way, as for the stirring apparatus of the said patent document 4, the width | variety of the stirring blade in the radial direction of a stirring tank is set in the range of 5-10% of the internal diameter (diameter) of a stirring tank. That is, the stirring device described in Patent Document 4 is, when viewed in a cross section of the stirring tank, the outer peripheral area of the stirring tank through which the stirring blade rotates, that is, upward (in the case of scraping rotation) or downward (by the stirring rotation) The outer peripheral area of the stirring tank where the discharge force of the stirring rotation directly acts is as narrow as about 19 to 36%, and the central area of the stirring tank where the stirring blade does not pass, that is, the discharge force by the stirring blade is directly The central region of the agitation tank that does not act on is widened to about 64 to 81%. For this reason, the stirring device described in Patent Document 4 has a flow (downward flow (downflow) if it is a scraping rotation) and an upward flow (upflow) if it is a scraping rotation on the center side of the stirring tank. ) Is unlikely to occur sufficiently. This fact is not a problem for the stirrer described in Patent Document 4 that targets a stirred product with medium viscosity (10 to 200 poise), but when mixing a stirred product with a high viscosity (200 to poise). As a result, there is a problem in that the circulation flow in the vertical direction is not sufficiently generated over the entire inside of the agitation tank, and there remains a problem that the mixing characteristics as a whole are not good.

  Therefore, the present invention can sufficiently generate a circulating flow in the vertical direction over the entire inside of the agitation tank, and as a result, the mixing characteristics as a whole are good even with a high viscosity agitation processed product. It is an object to provide a stirring device.

The stirring device according to the present invention includes a cylindrical stirring tank 1, a stirring shaft 2 disposed at the center of the stirring tank 1 and rotatable from outside the tank, and intermittently along the inner wall of the stirring tank 1. A plurality of stirring blades 7 that are arranged in a helical shape and are respectively attached to the stirring shaft 2 via the support arm 6, and extend from the inner wall of the stirring tank 1 at positions that do not interfere with the stirring blades 7. In each of the stirring devices attached to the support arm 8 and provided with a plurality of baffles 9,... Arranged closer to the center than the stirring blades 7,..., The width W ₁ of the stirring blade 7 in the radial direction of the stirring tank ₁ is The clearance C ₁ between the stirring blade 7 and the inner wall of the stirring tank 1 in the radial direction of the stirring tank 1 and the radial direction of the stirring tank 1 are set within a range of 10 to 20% of the inner diameter (diameter) of the stirring tank 1 it clearance C ₂ between the stirring blades 7 and the baffle 9 in It is characterized in that but set in the range of 3% or less of the inner diameter of the stirred tank 1 (diameter).

  According to the stirring device according to the present invention, when viewed in a cross-section of the stirring tank 1, the stirring blades 7 are rotated upwardly by the outer peripheral region of the stirring tank 1, that is, the stirring blades 7,. The outer peripheral area of the stirring tank 1 to which the discharge force directly acts (in the case of scraping rotation) is approximately 36 to 64%, which is wider than the conventional one, while the stirring blades 7,... Do not pass. The central region of the stirring tank 1, that is, the central region of the stirring tank 1 where the discharge force by the stirring blades 7,... Does not act directly is narrowed to about 36 to 64%, and the difference between the two is small. Become or disappear. Therefore, on the center side of the stirring tank 1, a flow (downward flow (downflow) if swept up rotation, upflow (upflow) if swept down rotation) is sufficiently generated, and as a result. The circulating flow in the vertical direction can be sufficiently generated throughout the stirring tank 1.

  In addition, when mixing two or more types of agitation products with different viscosities (more specifically, mixing a low viscosity agitation product into a high viscosity agitation product) The center side of the surface of the stirred product becomes a fixed point that is less likely to flow, and the low viscosity stirred product does not mix well with the high viscosity stirred product and accumulates on the center side of the surface of the stirred product (so-called )) May occur, resulting in a problem that mixing failure occurs. However, according to the stirring device according to the present invention, the upward discharge force by the rotating stirring blades 7 becomes larger in the scraping rotation than in the conventional case. As a result, the flow from the outer peripheral side to the center side on the surface of the agitated product is increased, so that “accumulation” can be eliminated.

Furthermore, when mixing two or more types of agitation processed products having different viscosities (more specifically, mixing a low viscosity agitation processed product into a high viscosity agitation processed product) The low-viscosity stirred product does not mix well with the high-viscosity stirred product, and is distributed along the inner wall of the stirring tank. However, according to the stirring device of the present invention, the stirring blade 7 and the inner wall of the stirring tank 1 in the radial direction of the stirring tank 1 may occur. clearance C ₁ between is set in the range of 3% or less of the inner diameter of the stirred tank 1 (diameter) and has both a gap is reduced, as a result, the engine speed decrease scraping, agitating blades 7, due to ... Because the discharge force acts suitably on the inner wall of the stirring tank 1 , It is possible to eliminate the "slip".

However, if the width W ₁ of the stirring blade 7 exceeds 20% of the inner diameter (diameter) of the stirring tank 1, the proportion of the outer peripheral region of the stirring tank 1 through which the stirring blades 7,. The flow balance in the vertical direction is lost, and uniform mixing is hindered.

Here, the stirring device according to the present invention includes the width W ₁ of the stirring blade 7 in the radial direction of the stirring tank 1, the width W ₂ of the baffle 9 in the radial direction of the stirring tank 1, and the stirring blade 7 in the radial direction of the stirring tank 1. And the clearance C ₁ between the inner wall of the stirring tank 1 and the clearance C ₂ between the stirring blade 7 and the baffle 9 in the radial direction of the stirring tank 1 is 15 of the inner diameter (diameter) of the stirring tank 1. It is preferable to set within a range of ˜30%.

  According to this configuration, the flow balance in the vertical direction can be made appropriate.

  Further, in the stirring device according to the present invention, the baffle 9 has an angle range of −10 to 90 degrees with respect to the tilt angle α of the stirring blade 7, more preferably −10 to 10 with respect to the tilt angle α of the stirring blade 7. A configuration in which the angle range is 15 degrees can be employed.

  According to such a configuration, the baffle effect works favorably, and if it is a scraping rotation, the effect of eliminating “scum” can be further enhanced, and if it is a scraping rotation, the effect of eliminating “slip” is further enhanced. Can do.

  Further, the stirring device according to the present invention has a configuration in which the upper end of the stirring blade 7 or the baffle 9 protrudes from the surface of the stirring processing product loaded in the stirring tank 1, that is, the stirring blade 7 or the baffle 9 has the stirring processing product. Such a configuration can be employed.

  According to such a configuration, the shearing force on the surface layer of the agitated material is effectively exerted by either the stirring blade 7 or the baffle 9 protruding from the surface of the surface layer of the agitated material loaded in the agitating tank 1. Therefore, in the operation of adding the low viscosity stirred product into the high viscosity stirred product, the low viscosity stirred product is preferably dispersed. If it is effectively eliminated and scraping rotation, “slip” will be eliminated more effectively, and it is possible to achieve better mixing with different viscosities regardless of whether it is scraping rotation or scraping rotation. It becomes.

  Further, the stirring device according to the present invention further includes a bottom paddle blade 11 which is disposed along the bottom of the stirring tank 1 and is attached to the stirring shaft 2 so as to be inclined in the vertical direction or in the same direction as the stirring blades 7. And a bottom ribbon blade 14 made of a double helix, which is arranged along the bottom of the stirring tank 1 and is attached to the stirring shaft 2 vertically or inclined in the same direction as the stirring blade 7. It is possible.

  According to these configurations, the bottom paddle blade 11 and the bottom ribbon blade 14 forcibly push up the stir processed product stagnated and deposited on the bottom of the stirring tank 1 regardless of whether it is swung up or swung down. The mixing characteristics of the agitation-treated product having a viscosity and two or more types of agitation-treated products having different viscosities are further improved.

Next, in the stirring method according to the present invention, when boiling polymerization is performed using any one of the stirring devices described above, the stirring power per unit volume is 0.2 to 5.0 kW / m ³ , preferably 0.8. or be those characterized by stirring as 3~3.0kW / m ^3, with reference to any one of the stirring device, a low viscosity that the viscosity difference in the stirring treatment of high viscosity exceeds 10,000 times when the dispersed mixture was charged with stirring treatment of, stirring power the 0.2~5.0kW / m ³ per unit volume, it preferably stirring as 0.3~3.0kW / m ³ It is characterized by.

  According to the stirring method of the present invention, by setting the power range to the above range, not only can stirring be performed efficiently, but also energy loss with respect to the mixing effect can be suppressed.

  Moreover, the stirring method which concerns on this invention can employ | adopt the thing of the viscosity whose stirring processed material is 200-10000 poise.

  As described above, according to the stirring device according to the present invention, the circulating flow in the vertical direction can be sufficiently generated over the entire inside of the stirring tank. When mixing two or more types of agitation products with different viscosities, not only the properties are improved, but also effectively suppresses “scumming” of low viscosity agitation products and “slip” between the agitation products. As a result, it is possible to prevent the occurrence of mixing failure and to improve the overall mixing characteristics. Therefore, if the stirring device according to the present invention, the stirring process product is 10,000 times in boiling polymerization at a viscosity exceeding 200 poise, or the operation of introducing the low viscosity stirring process product into the high viscosity stirring process product. Uniform dispersion mixing with a viscosity difference exceeding 1 is possible.

<First embodiment>
Hereinafter, a stirring apparatus according to an embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the agitation apparatus according to the present embodiment is provided along an agitation tank 1, an agitation shaft 2 that is disposed at the center of the agitation tank 1 and can be rotated from the outside of the tank, and an inner wall of the agitation tank 1. And a plurality of agitation blades 7 attached to the agitation shaft 2 via the support arm 6 respectively, and the supports arranged at positions that do not interfere with the agitation blades 7. A plurality of baffles (inner baffles) 9, which are attached to the inner wall of the agitation tank 1 via the arm 8 and are arranged closer to the center than the agitation blades 7,. And a pair of bottom paddle blades 11, 11 attached to the stirring shaft 2 via the support arm 10.

  The stirring tank 1 is a cylindrical stirring tank, and includes a cylindrical straight body part, a bottom part having a semi-elliptical cross section attached to the lower end of the straight body part, and a top part attached to the upper end of the straight body part. The shaft core is held so as to be vertical. When the drive device is disposed below the bottom of the stirring tank 1, the upper end of the stirring shaft 2 is supported via a bearing 3 provided at the top of the stirring tank 1 and disposed below the bottom of the stirring tank 1. The lower end is connected to the driving device via a coupling. The driving device can also be disposed above the top of the stirring tank 1 via a coupling. In that case, the bearing 3 is provided in the bottom part of the stirring tank 1, and the lower end of the stirring shaft 2 is supported.

A pair of stirring blades 7 are disposed in the middle of the straight body portion of the stirring tank 1 (a pair of stirring blades 7A ₁ and 7B _{1 in} the upper stage), and a pair of stirring blades 7 are arranged between the stirring blade 7 and the bottom paddle blade 11 in the upper stage. (A pair of stirring blades 7A ₂ and 7B _{2 in the} lower stage). More specifically, in each stage, the pair of support arms 6 and 6 extend in opposite directions so that the pair of stirring blades 7 and 7 have a phase difference of 180 degrees, and the pair of stirring blades 7 and 7 in the upper stage 7 and the pair of stirring blades 7 and 7 in the lower stage have a phase difference of 90 degrees, and each stirring blade 7 is disposed. The stirring blade 7 is a so-called paddle blade that is an arc-shaped flat plate.

Further, as shown in FIG. 2, the stirring blade 7 is supported by the support arm 6 while being inclined with respect to the rotation direction. More specifically, the stirring blade 7 is inclined so that one side in the rotation direction (counterclockwise side in FIG. 2) is downward, and the inclination angle α with respect to the rotation direction is 30 degrees. Therefore, the stirring blade 7A ₁ in the upper stage and the stirring blade 7A ₂ in the lower stage preceding the stirring blade 7A _{1 in the} rotational direction (with a phase difference of 90 degrees) are intermittently helical along the inner wall of the stirring tank 1. (First helical), and the stirring blade 7B ₁ in the upper stage and the stirring blade 7B ₂ in the lower stage preceding the stirring blade 7B ₁ (with a phase difference of 90 degrees) in the rotational direction An intermittent helical structure is formed along the inner wall (second helical), and the two helical lines have a phase difference of 180 degrees, which is similar to a so-called double helical ribbon wing.

  The tip of the stirring blade 7 and the support arm 6 is provided with a through hole (not shown) for inserting a bolt (not shown) as a fastening means. The stirring blade 7 is fastened by fastening bolts and nuts. It is attached to the tip of the support arm 6. In addition, the through hole has a larger diameter than the threaded portion of the bolt, and the clearance between the stirring blade 7 and the inner wall of the stirring tank 1 can be adjusted by changing the mounting position of the stirring blade 7 with respect to the support arm 6. It is said.

The baffle 9 is for generating a shearing force on the stirred product by interaction with the stirring blade 7 and promoting mixing, and is arranged so as to be inclined in the opposite direction to the stirring blade 7. Three above the stirring blade 7, between the stirring blade 7 at the upper stage and the stirring blade 7 at the lower stage, and below the stirring blade 7 at the lower stage (that is, between the stirring blade 7 and the bottom paddle blade 11 at the lower stage). Steps are arranged (three baffles 9A ₁ , 9A ₂ , 9A ₃ from upper to lower). The baffle 9 is a pipe baffle, and the upper and middle baffles 9 have the same length, and the lower baffle 9 is formed longer (with the lower end protruding downward).

  Since the baffle 9 is provided as described above, the support arm 8 to which the baffle 9 is attached is located above the stirring blade 7 (support arm 6 to which the support arm 6 is attached) in the upper stage, the stirring blade 7 (support arm 6 to which the support arm 6 is attached) and Between the stirring blade 7 (the support arm 6 to which the stirring blade 7 is attached), and below the stirring blade 7 (the support arm 6 to which the mounting arm 6 is attached) in the lower stage (that is, the stirring blade 7 (the support arm 6 to which the lower arm is attached)) and the bottom paddle blade 11 It is attached to the inner wall of the agitation tank 1 at three positions (with the support arm 10 to which is attached).

  Accordingly, the stirring blade 7 in the upper stage passes through a region surrounded by the upper wall of the baffle 9 in the upper stage, the support arm 8 to which the baffle 9 is attached and the inner wall of the stirring tank 1 at the time of rotation, and the lower half in the baffle 9 in the middle stage. The region surrounded by the support arm 8 to which the baffle 9 is attached and the inner wall of the agitation tank 1 passes during rotation, while the agitation blade 7 in the lower stage is the baffle 9 whose upper half is the middle stage, the support arm 8 to which the baffle 9 is attached and the agitation The region surrounded by the inner wall of the tank 1 passes during rotation, and the lower half passes through the lower baffle 9, the support arm 8 to which the baffle 9 is attached, and the region surrounded by the inner wall of the stirring tank 1 during rotation.

  And the through-hole (not shown) for inserting the bolt (not shown) as a fastening means is provided in the front-end | tip part of the baffle 9 and the support arm 8, and the baffle 9 is a support arm by fastening bolt and nut. 8 is attached to the tip. In addition, the through hole has a larger diameter than the screw portion of the bolt, and the attachment position of the baffle 9 with respect to the support arm 8 can be varied to adjust the clearance between the stirring blade 7 and the baffle 9.

  Returning to FIG. 1, a pair of bottom paddle blades 11 is disposed at the bottom of the stirring tank 1 (a pair of stirring blades 11A and 11B). More specifically, at the lower end of the stirring shaft 2, the pair of support arms 10 and 10 extend in opposite directions, and the pair of stirring blades 11A and 11B are attached with a phase difference of 180 degrees. Further, the pair of support arms 10 and 10 to which the pair of bottom paddle blades 11 and 11 are attached are arranged on the stirring shaft 2 with a phase difference of 90 degrees from the pair of support arms 6 and 6 to which the pair of stirring blades 7 and 7 are attached in the lower stage. Therefore, the pair of stirring blades 7 and 7 and the pair of bottom paddle blades 11 and 11 in the lower stage have a phase difference of 90 degrees.

  Further, as shown in FIG. 3, the bottom paddle blade 11 is supported by the support arm 10 while being inclined with respect to the rotation direction. More specifically, the bottom paddle blade 11 is inclined such that one side in the rotation direction (counterclockwise side in FIG. 3) is downward, and the inclination angle β with respect to the rotation direction is 45 degrees. Therefore, the pair of bottom paddle blades 11 and 11 are attached to the pair of support arms 10 and 10 extending from the lower end portion of the stirring shaft 2 with a phase difference of 180 degrees at an intersecting angle of 90 degrees.

In addition, since the bottom paddle blade 11 is as described above, the stirring blade 7A ₁ in the upper stage and the stirring blade 7A _{2 in the} lower stage are more advanced than the stirring blade 7A _{2 in the} rotational direction (with a phase difference of 90 degrees). The first helical structure including the bottom paddle blade 11A is configured. On the other hand, the stirring blade 7B ₁ in the upper stage and the stirring blade 7B _{2 in the} lower stage are more than the stirring blade 7B ₂ (with a phase difference of 90 degrees). A so-called double helical ribbon blade that forms the second helical structure including the bottom paddle blade 11B that precedes the rotation direction and has two helical lines having a phase difference of 180 degrees from the straight body portion to the bottom portion of the stirring tank 1 It becomes a form similar to.

  Further, the bottom paddle blade 11 is a so-called paddle blade whose lower end edge is a flat plate along the cross-sectional shape of the bottom of the stirring tank 1, and a recess 11a that allows the lower end of the lower baffle 9 to pass during rotation. At the upper side, a lower arm baffle 9, a support arm 8 to which the baffle 9 is attached, and an extending portion 11 b that passes through an area surrounded by the inner wall of the stirring tank 1 at the outside of the rotation. A notch 11c is provided below to allow a temperature sensor (not shown) protruding from the bottom to pass through.

  The bottom paddle blade 11 is a combination of three flat plates. As shown in FIG. 4, the bottom paddle blade 11 is attached to the first member 11X attached to the support arm 10 and the outer end of the first member 11X. It consists of the 2nd member Y which comprises the extension part 11b, and the 3rd member Z attached to the lower end edge of the 1st member 11X, The said recessed part 11a is formed between the 1st member 11X and the 2nd member 11Y. The notch 11c is formed in the third member 11Z.

As described above, the stirring device according to the present embodiment is provided along the cylindrical stirring tank 1, the stirring shaft 2 disposed in the central portion of the stirring tank 1 and rotatable from the outside of the tank, and the inner wall of the stirring tank 1. A plurality of stirring blades 7, which are intermittently arranged in a helical shape and are respectively attached to the stirring shaft 2 via the support arm 6, and from the inner wall of the stirring tank 1 at positions not interfering with the stirring blades 7,. In a stirrer equipped with a plurality of baffles 9,... Attached to each extending support arm 8 and disposed more centrally than the stirrer blades 7,... Or a stirring blade in the radial direction of the stirring tank 1 to enable uniform dispersion and mixing with a viscosity difference exceeding 10,000 times in the operation of putting the low-viscosity stirring product into the high-viscosity stirring product The width W _{1 of} 7 is 10 to 2 of the inner diameter (diameter) of the stirring tank 1 It is set in the range of 0%, between the stirring blades 7 and baffle 9 in the radial clearance C ₁ and stirred tank 1 between the stirring blade 7 in the radial direction of the stirred tank 1 and the inner wall of the stirred tank 1 Each of the clearances C ₂ is configured to be within a range of 3% or less of the inner diameter (diameter) of the stirring tank 1.

  Therefore, when the stirring device according to the present embodiment is viewed in the cross section of the stirring tank 1, the discharge force by the stirring blade 7, the outer peripheral area of the stirring tank 1 through which the stirring blades 7,. The outer peripheral area of the stirring tank 1 acting as large as about 51% and the central area of the stirring tank 1 where the stirring blades 7,... Do not pass, that is, the discharge force by the stirring blades 7,. This is almost the same as the central region (about 49%) of the stirring tank 1, and accordingly, upward or downward flow (upflow or downward flow) occurs sufficiently and over a wide range on the center side of the stirring tank 1. As a result, the circulating flow in the vertical direction can be sufficiently generated throughout the entire stirring tank 1.

Further, the stirring device according to the present embodiment has a large upward discharge force due to the rotary stirring blades 7... Due to the scooping rotation, and as a result, the flow from the outer peripheral side to the center side on the surface of the stirring processed product increases. For this reason, “scumming” can be eliminated, and the clearance C ₁ between the stirring blade 7 and the inner wall of the stirring tank 1 in the radial direction of the stirring tank 1 is 3% or less of the inner diameter (diameter) of the stirring tank 1. As a result, the discharge force by the stirring blades 7,... Acts favorably on the inner wall of the stirring tank 1 by the scraping rotation, so that “slip” can be eliminated.

  Therefore, according to the stirrer according to the present embodiment, it is possible to generate a sufficiently vertical circulation flow throughout the entire stirring tank 1, and as a result, even a highly viscous stirred product as a whole. When mixing two or more types of agitated products with different viscosities, it is effective to prevent “stagnation” of low-viscosity agitated products and “slip” between the agitated products. As a result, it is possible to prevent the occurrence of mixing failure and to improve the overall mixing characteristics.

  Specifically, according to the stirring device described in Patent Document 4, the viscosity of the stirred product is limited to 200 poise, but according to the stirring device according to the present embodiment, high-viscosity mixing up to 10000 poise is possible. . Thus, for example, boiling polymerization with a viscosity of 200 poise is possible. Further, according to the stirring device described in Patent Document 4, the viscosity difference is limited to 200,000 times (for example, 20,000 cp vs. 0.1 cp), but according to the stirring device according to the present embodiment, 1.5 million times (for example, , 150,000 cp vs. 0.1 cp) can be mixed with different viscosities. Therefore, uniform dispersion mixing with a viscosity difference exceeding 200,000 times, for example, in the operation of introducing the low viscosity liquid into the high viscosity liquid becomes possible.

Further, the stirring device according to the present embodiment further includes a bottom paddle blade 11 that is disposed along the bottom of the stirring tank 1 and is attached to the stirring shaft 2 so as to be inclined with respect to the rotation direction in the same manner as the stirring blades 7. Prepare. Then, the bottom paddle blade 11 is provided with a recess 11a for passing the lower end of the lowermost baffle 9A ₃ during rotation upwards, the lowest of the baffle 9A _3, the support arm 8 and the stirred tank attaching the baffle 9A ₃ 1 has an extending portion 11b that passes through a region surrounded by the inner wall at the time of rotation, is disposed on or near the extension line of the helical line of the stirring blades 7,..., And extends to the extension line of the helical line Tilt along. Moreover, the inclination angle β with respect to the rotation direction of the bottom paddle blade 11 is set to be larger than the inclination angle α with respect to the rotation direction of the stirring blade 7. With these configurations, regardless of whether it is rotating up or down, the bottom paddle blades 11 and 11 forcibly push up the stir processed product that stagnates on the bottom of the stirring tank 1 to thereby produce a high viscosity stirring process. Mixing characteristics of two or more kinds of stirring processed products having different materials and viscosities are further improved.

In addition, in the stirring device according to the present embodiment, at least the uppermost baffle 9A ₁ is more than the uppermost stirring blades 7A ₁ and 7B ₁ so as to be applied to the liquid level R of the stirring processed product loaded in the stirring tank 1. In the case of scraping rotation, “slip” is eliminated, and in the case of scraping rotation, “pumping” is eliminated, so that it is possible to achieve better mixing with different viscosities. preferable.

Further, in the stirring device according to this embodiment, the mounting position of the stirring blade 7 with respect to the support arm 6 is variable so that the clearance C ₁ between the stirring blade 7 and the inner wall of the stirring tank 1 can be adjusted. The clearance C ₁ is wide, underpowered, flow stagnation, caused a decrease heat transfer, whereas, if the clearance C ₁ is narrow, but can cause overloading, according to this configuration, the clearance C ₁ in a proper state Can be adjusted.

Further, in the stirring device according to the present embodiment, the attachment position of the baffle 9 with respect to the support arm 8 is variable so that the clearance C ₂ between the stirring blade 7 and the baffle 9 can be adjusted. Advantages of this point is the same as the structure that allows adjusting the clearance C ₁ between the stirring blades 7 and the inner wall of the stirred tank 1.

  In addition, although the stirring apparatus which concerns on this embodiment is the same also in the following embodiment, when performing boiling polymerization, it is preferable to carry out by the scooping rotation from which the feed direction of a stirring processed material becomes upward. This not only prevents the bubbles generated around the stirring shaft 2 from being retained in the stirring tank 1, but also allows the generated bubbles to be made fine by the shearing force of the stirring. This is because it can be prevented. Here, boiling polymerization is a method of polymerizing a stirred product while boiling it. The stirred product can be boiled to remove the heat of polymerization, and the polymerization can be performed stably. Further, in the case of performing boiling polymerization, the liquid surface height H with respect to the inner diameter (diameter) D of the stirring tank 1 is referred to with reference to FIG. 1 (and FIG. 5). It is efficient to set the ratio of 0.6 to 1.5. Stir processed products that can be polymerized by boiling polymerization are not particularly limited, but monomers such as styrene, acrylic ester, methacrylic ester, polybutadiene rubber, natural rubber, styrene-butadiene copolymer rubber, etc. Examples thereof include rubber and copolymers thereof.

Moreover, although the stirring apparatus which concerns on this embodiment is also the same also in the following embodiment, it is preferable that the stirring power shall be 0.2-5.0 kW / m < ³ >. By setting within this range, not only can stirring be performed efficiently, but also energy loss with respect to the mixing effect can be suppressed. On the other hand, if the value is less than 0.2, there is a problem that a sufficiently developed vertical circulation flow cannot be obtained, and the desired performance cannot be obtained. On the other hand, if the value exceeds 5.0, the input energy increases. However, there is a problem that it is difficult to establish as a device because heat generation due to agitation occurs due to the increased power and it becomes difficult to establish a heat balance. is there.

<Second embodiment>
Hereinafter, a stirring device according to another embodiment of the present invention will be described with reference to FIGS. The difference between the stirrer according to this embodiment and the stirrer according to the first embodiment is the type of the bottom blade, and the rest is basically the same. Numbering and omitting the explanation.

  The bottom blade of the stirring device according to the present embodiment is a bottom ribbon blade 14 corresponding to the bottom of the stirring tank 1, and the tip (bottom end) of the bottom ribbon blade 14 is supported on a support arm 15 protruding from the lower end of the stirring shaft 2. ) The top surface is attached. The bottom ribbon blade 14 is a helical ribbon blade provided so as to form a helical surface and extend toward the center of the bottom of the stirring tank 1. In other words, the bottom ribbon blade 14 is disposed in a section starting from the tip of the lowest support arm 10 located at the boundary between the straight body portion and the bottom portion of the stirring tank 1 and reaching the vicinity of the bottom center.

  Further, the bottom ribbon blade 14 is displaced in the radial direction with respect to the flat ribbon 14 ′ (see FIG. 8A) that is gradually displaced radially inward toward the tip and gradually narrows toward the tip. It has a shape (see FIG. 8 (b)) in which the outer side is down and the twist angle is gradually increased toward the tip. Incidentally, the twist angle (final twist angle) at the tip (lower end) of the bottom ribbon blade 14 is set to 45 degrees.

  The support arm 15 is located at the same height as the lowest support arm 10 and is arranged with a phase difference of 90 degrees. Moreover, a pair of support arms 15 is provided to support the tips of the two bottom ribbon blades 14 and 14 (a pair of bottom ribbon blades 14A and 14B). That is, the pair of support arms 15 extends from the agitation shaft 2 in opposite directions, and is disposed with a phase difference of 180 degrees and a phase difference of 90 degrees with the pair of support arms 10 and 10 at the bottom. The bottom ribbon blades 14 and 14 are supported so as to have a phase difference of 180 degrees.

Moreover, since the bottom ribbon blade 14 is as described above, the stirring blade 7A ₁ in the upper stage and the stirring blade 7A _{2 in the} lower stage are preceded in the rotational direction (with a phase difference of 90 degrees) than the stirring blade 7A _2. including bottom ribbon blade 14A constitute the first helical that, whereas, the stirring blade 7B ₂ in the stirring blades 7B ₁ and the lower in the upper (with a phase difference of 90 degrees) than the stirring blade 7B ₂ A so-called double helical ribbon blade, which includes the bottom ribbon blade 14B preceding the rotation direction and constitutes the second helical, and has two helical lines having a phase difference of 180 degrees from the straight body portion to the bottom portion of the stirring tank 1. It becomes a form similar to.

  Further, each support arm 15 has a hanging part that hangs outward in an oblique diameter, and the tip of the hanging part is cut at 45 degrees with respect to the rotation direction, so that the top surface of the bottom ribbon wing 14 has an upper surface. The bottom ribbon blade 14 is supported by the support arm 15 in this contact state. In this embodiment, the support arm 15 is formed with a drooping portion by bending a straight pipe at a predetermined position. The bending amount of the support arm 15 is lowered by adding a twist to the ribbon 14 '. It is set corresponding to the height difference of the bottom ribbon blade 14.

As described above, in the stirring device according to this embodiment, similarly to the stirring device according to the first embodiment, the width W ₁ of the stirring blade 7 in the radial direction of the stirring tank 1 is 10 to 20% of the inner diameter (diameter) of the stirring tank 1. The clearance C ₁ between the stirring blade 7 and the inner wall of the stirring tank 1 in the radial direction of the stirring tank 1 is set within a range of 3% or less of the inner diameter (diameter) of the stirring tank 1. Since it is a structure, it can fully generate the up-and-down direction circulation flow in the inside of the stirring tank 1, and as a result, even if it is a highly viscous stirring processed material, the mixing characteristic as a whole becomes favorable. In addition, in the case of mixing two or more types of agitation processed products having different viscosities, it is possible to effectively suppress “scumming” of low viscosity agitation processed products and “slip” between the agitation processed products, As a result, it is possible to prevent the occurrence of mixing failure, and the mixing characteristics as a whole. Property is improved.

  Further, the stirring device according to the present embodiment further includes a bottom ribbon blade 14 that is disposed along the bottom of the stirring tank 1 and is attached to the stirring shaft 2 so as to be inclined with respect to the rotation direction in the same manner as the stirring blades 7. Prepare. The bottom ribbon blade 14 is gradually displaced inward in the radial direction toward the tip, and gradually becomes narrower toward the tip. The bottom ribbon blade 14 has a lower outer side in the width direction and toward the tip. It has a shape with a twist added so that the twist angle gradually increases. Further, the support arm 5 extends from the lower end portion of the stirring shaft 2, and the support arm 5 is attached to the top surface of the tip of the bottom ribbon blade 14. With these configurations, regardless of whether it is rotating up or down, the bottom ribbon blades 14 and 14 forcibly push up the agitated material that is stagnated at the bottom of the agitation tank 1, so that a high viscosity agitation treatment is performed. The mixing characteristics of two or more kinds of agitation processed products having different properties and viscosities are further improved.

  In addition, the stirring apparatus which concerns on this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

  For example, in the above embodiment, the stirring blades 7 are arranged in two stages and the baffles 9 are arranged in three stages. However, the present invention is not limited to this, and the present invention may include many more. Needless to say. Further, it is not essential to have a step. Therefore, in the case of a two-row intermittent helical, the stirring blade 7 in one helical and the stirring blade 7 in the other helical are displaced in the axial length direction. It doesn't matter.

  Moreover, in the said embodiment, although the stirring blade 7 is comprised with a flat plate without a twist, it is comprised with the curved board by which the stirring blade was twisted along the helical line like the stirring apparatus which concerns on patent document 4, for example. It may be a thing. The “helical shape” according to the present invention is intended to include both “flat plate” and “curved surface plate”. However, the cost can be reduced because the flat plate is easier to process and manufacture.

  Moreover, in the said embodiment, although the inclination angle (alpha) of the stirring blade 7 is 30 degree | times, it is not limited to this, It can select from an appropriate angle range.

In the above embodiment, the amount of liquid is adjusted so that the uppermost baffle 9A ₁ is applied to the liquid level R of the agitation processed product loaded in the agitation tank 1, but the uppermost agitation blades 7A ₁ and 7B are adjusted. The meshing area of ₁ and the uppermost baffle 9 </ b> A ₁ may be applied to the liquid level R of the agitation processed product loaded in the agitation tank 1.

  Further, in the above-described embodiment, the plurality of baffles 9,... Are arranged vertically and arranged only in one place when viewed in the rotational direction, but with a predetermined interval in the rotational direction (for example, , A counter position with a phase difference of 180 degrees and a tri-section position with a phase difference of 120 degrees) may be provided.

  Moreover, in the said embodiment, although the drive device for rotationally driving the stirring shaft 2 from the tank outside is provided in the bottom part side of the stirring tank 1, you may provide in the top part side of the stirring tank 1. FIG.

  Moreover, in the said embodiment, although the bottom part of the stirring tank 1 employs a semi-elliptical cross-sectional shape, it may be a dish shape or a conical bottom part having an obtuse apex angle.

  Moreover, in the said embodiment, although the bottom paddle blade | wing 11 and the bottom ribbon blade | wing 14 were arrange | positioned at the bottom part of the stirring tank 1, it is not limited to this, It is made to arrange | position the blade | wing of another form. Alternatively, these blades may not be arranged at the bottom of the stirring tank 1.

  In the above embodiment, the support arm 8 to which the baffle 9 is attached is attached to the inner wall of the agitation tank 1, so that the attachment angle of the baffle 9 is fixed. However, as shown in FIG. By changing the angle, the baffle 9 is within the range of −10 degrees to the vertical direction (that is, 90 degrees), more preferably −10 to 10 degrees, with 0 degree being parallel to the inclination angle α of the stirring blade 7. It is possible to change within a range of 15 degrees.

The longitudinal cross-sectional view of the stirring apparatus which concerns on 1st embodiment is shown. (A) is the sectional view on the AA line of FIG. 1, (b) shows the C arrow directional view of (b). (A) is a cross-sectional view taken along the line BB in FIG. 1, and (B) is a view taken in the direction of arrow D in (A). The exploded view of the bottom paddle blade used for the stirring device is shown. The longitudinal cross-sectional view of the stirring apparatus which concerns on 2nd embodiment is shown. FIG. 6 is a cross-sectional view taken along line EE in FIG. 5. It is principal part longitudinal cross-sectional view of the same stirring apparatus, Comprising: The F arrow directional view of FIG. 5 is shown. It is the lower part shape of the helical paddle blade used for the stirring device, and (A) shows a state diagram before adding a twist, and (B) shows a state diagram after adding a twist. A state diagram showing in what angle range the baffle is arranged with respect to the stirring blade is shown.

Explanation of symbols

1 ... stirred tank, 2 ... stirring shaft, 3 ... bearing, 6 ... support _{arm, 7 (7A 1, 7A 2} , 7B 1, 7B 2) ... stirring blade, 8 ... support arm, 9 ... baffle (9A _1, 9A ₂ , 9A ₃ ), 10 ... support arm, 11 (11A, 11B) ... bottom paddle blade, 11a ... concave portion, 11b ... extended portion, 14 (14A, 14B) ... bottom ribbon blade, 15 ... support arm, D ... Inner diameter (diameter) of stirring tank, H: liquid level height, R: liquid level, W ₁ ... width of stirring blade 7 in radial direction of stirring tank 1, W ₂ ... width of baffle 9 in radial direction of stirring tank 1 C ₁ ... clearance between the stirring blade 7 and the inner wall of the stirring tank 1 in the radial direction of the stirring tank 1, C ₂ ... clearance between the stirring blade 7 and the baffle 9 in the radial direction of the stirring tank 1

Claims (10)

Cylindrical agitation tank (1), agitation shaft (2) disposed at the center of the agitation tank (1) and rotatable from outside the tank, and intermittently along the inner wall of the agitation tank (1) A plurality of stirring blades (7,...) Arranged in a helical shape and attached to the stirring shaft (2) via the support arms (6), respectively, and stirring at positions that do not interfere with the stirring blades (7,...) In an agitation apparatus comprising a plurality of baffles (9,...) Attached to the support arms (8) respectively extending from the inner wall of the tank (1) and disposed closer to the center than the agitation blades (7,...). The width (W ₁ ) of the stirring blade (7) in the radial direction of the stirring tank (1) is set within a range of 10 to 20% of the inner diameter (diameter) of the stirring tank (1), and the stirring tank (1) radially above the clearance between the inner wall of the stirred tank and stirred in the radial direction blade (7) (1) (C ₁₎ and stirred tank (1) Stirring each clearance (C ₂₎ is characterized in that it is set in a range inside diameter of less than 3% (diameter) of the stirred tank (1) between the stirring and the blades (7) and baffles (9) in apparatus. The width (W ₁ ) of the stirring blade (7) in the radial direction of the stirring tank (1), the width (W ₂ ) of the baffle (9) in the radial direction of the stirring tank (1), and the radial direction of the stirring tank (1) Clearance (C ₁ ) between the stirring blade (7) and the inner wall of the stirring vessel (1), and clearance between the stirring blade (7) and the baffle (9) in the radial direction of the stirring vessel (1) (C ₂ ) Is set within a range of 15 to 30% of the inner diameter (diameter) of the agitation tank (1).   The stirrer according to claim 1 or 2, wherein the baffle (9) is arranged so as to fall within an angle range of -10 to 90 degrees with respect to the inclination angle (α) of the stirring blade (7).   The stirrer according to claim 3, wherein the baffle (9) is arranged so as to fall within an angle range of -10 to 15 degrees with respect to the inclination angle (α) of the stirring blade (7).   The stirring according to any one of claims 1 to 4, wherein the stirring blade (7) or the baffle (9) is disposed so that an upper end of the stirring blade (7) protrudes from a surface of the stirring treatment product loaded in the stirring tank (1). apparatus.   A bottom paddle blade (11) disposed along the bottom of the stirring vessel (1) and attached to the stirring shaft (2) so as to be inclined vertically or in the same direction as the stirring blade (7, ...). Item 6. The stirring device according to any one of Items 1 to 5.   A bottom ribbon blade (14) made of a double helix (14) disposed along the bottom of the stirring tank (1) and attached to the stirring shaft (2) vertically or inclined in the same direction as the stirring blade (7,...). , 14) The stirring device according to any one of claims 1 to 6, further comprising: When performing the boiling polymerization using a stirring device according to claims 1-7, stirring method characterized by stirring the stirring power per unit volume as 0.2~5.0kW / m ^3. When using the stirrer according to any one of claims 1 to 7, when a low-viscosity stirred product whose viscosity difference exceeds 10,000 times is added to a high-viscosity stirred product, the unit is dispersed. stirring method characterized by stirring the stirring power per unit volume as 0.2~5.0kW / m ^3.   The stirring method according to claim 8 or 9, wherein the stirring treatment product has a viscosity of 200 to 10,000 poise.

Images