JP6498418B2 - Evaporator - Google Patents

Description

  The present invention relates to an evaporation apparatus. More specifically, the present invention relates to an evaporation apparatus that can prevent splashing of liquid when the liquid is sprayed onto a heated tank wall of a stirring tank using a spraying unit.

  2. Description of the Related Art Conventionally, an evaporation apparatus that performs desired distillation, precipitation of crystals, concentration of active ingredients, and the like through evaporation of the liquid by heating the liquid charged in the agitation tank is known. The evaporated liquid is collected by, for example, collecting in a condenser provided outside the stirring tank and aggregating.

  However, in conventional evaporators, droplets are generated in the stirring tank due to bumping in the stirring tank or severe collision of liquid with the stirring tank through stirring, and the splash reaches the condenser. It has been pointed out to do. Such a phenomenon is also called splash entrainment. Since entrainment may cause the original liquid to be mixed into the recovered liquid, the quality of the recovered liquid may be reduced.

  On the other hand, in recent years, an evaporation apparatus P as shown in FIG. 10 is known (Patent Document 1). In the stirring tank P10, the evaporation device P has a liquid spray part called a wall wetter that can rotate in the stirring tank P10 according to the rotation of the shaft extending from the motor P40 on the tank wall P11 set to a high temperature by heating the jacket P12. By using P20, an appropriate amount of liquid can be supplied to the tank wall P11. Thereafter, the vapor generated at the tank wall P11 is collected at the vapor outlet P13, and the liquid is collected by aggregating with a condenser (not shown) provided in communication with the vapor outlet P13.

  In the evaporator P using the wall wetter P20 shown in FIG. 10, the wall wetter P20 lifts the liquid by centrifugal force and sprays the liquid so that the liquid collides with the tank wall P11. Entrainment can be avoided. Here, in order to appropriately supply the liquid in the stirring tank P10 to the tank wall P11 through the wall wetter P20, it is necessary to rotate the wall wetter P20 at a high speed.

  However, as the liquid is rotated at a higher speed, the liquid is ejected more vigorously onto the tank wall P11 of the agitation tank, so that the liquid that has collided with the tank wall P11 may rebound and become droplets D. The splash D may move to the evaporation outlet P13 along with the rising airflow of the steam generated on the tank wall P11 (see the two-dot chain arrow in FIG. 10) and may reach a condenser (not shown).

  In order to avoid mixing of the original liquid due to the entrainment of the droplets, additional devices such as a saveall, a mist eliminator, and a centrifugal mist (bubble) prevention device are separately installed in the evaporation device P shown in FIG. However, it has been pointed out that such an additional apparatus has a complicated structure, and maintenance and repair including cleaning work and the like are complicated.

International Publication No. 2002/026374

  The present invention is intended to solve the above problems, and the object of the present invention is to prevent the occurrence of splashes even when the spray part such as a wall wetter is rotated at a high speed, It is another object of the present invention to provide an evaporation device that is simple in structure and can be freed from the complexity of maintenance and repair.

The present invention is an evaporation apparatus comprising: a sealable stirring tank having a steam outlet; a jacket for heating the tank wall of the stirring tank; and a sprinkling unit for spraying liquid onto the tank wall of the stirring tank. There,
here,
The liquid dispersion part is composed of a rotating shaft and one or more bowl-shaped members having a flow path for flowing the liquid and attached to the rotating shaft; and the liquid of the bowl-shaped member It is an evaporation apparatus provided with a splash reducer for reducing the amount of splash produced by collision of the liquid with the tank wall in the stirring tank in the vicinity of the tip in the flow direction.

  In one embodiment, the splash reducer includes an auxiliary hook-shaped member having an auxiliary flow path for passing the liquid, and the auxiliary hook-shaped member extends from a tip portion of the hook-shaped member in the liquid flow direction. The auxiliary hook-shaped member is bent or curved from the axial direction of the hook-shaped member at a joint portion between the auxiliary hook-shaped member and the hook-shaped member, and the liquid is supplied to the auxiliary hook-shaped member. Can be discharged in a direction substantially parallel to the tank wall.

  In one embodiment, the splash reducer includes an auxiliary hook-shaped member having an auxiliary flow path for passing the liquid, and the auxiliary hook-shaped member extends from a tip portion of the hook-shaped member in the liquid flow direction. And is bent or curved in a direction substantially parallel to the tank wall from the axial direction of the hook-shaped member at a joint portion between the auxiliary hook-shaped member and the hook-shaped member.

  In one embodiment, the splash reducer includes a member that collects splashes generated by colliding with the tank wall.

  In a further embodiment, the member for collecting the splash generated by colliding with the tank wall is in the direction of rotation of the bowl-shaped member along the bowl-shaped member in the vicinity of the tip of the bowl-shaped member in the liquid flow direction. On the other hand, it is a plate-like member provided on the back side of the flange-like member.

  In a still further embodiment, the plate-like member is provided so as to be substantially perpendicular to the rotation direction of the bowl-like member.

  In a further embodiment, the member for collecting the splash generated by colliding with the tank wall is a first member disposed so as to cover the flow path of the bowl-shaped member in the vicinity of the tip of the bowl-shaped member in the liquid flow direction. It is the 2nd auxiliary hook-shaped member which has 2 auxiliary flow paths.

  According to the present invention, when performing desired distillation, precipitation of crystals, concentration of active ingredients, and the like through evaporation of the liquid, the amount of droplets generated by collision between the liquid and the tank wall in the apparatus is reduced. Therefore, entrainment of the droplets on the condenser can be prevented, and the possibility that impurities are mixed into the obtained substance (for example, distilled liquid) can be remarkably reduced. Furthermore, it is not particularly necessary to add a device having a complicated structure to avoid such entrainment. Further, since the structure of the entire evaporator is not complicated, maintenance and repair including cleaning work and the like are easy.

It is the schematic which shows one Embodiment of the evaporation apparatus of this invention. It is a perspective view which represents typically an example of the bowl-shaped member which can be used for the spray part which comprises the evaporation apparatus of this invention. It is the schematic which shows another embodiment of the evaporation apparatus of this invention. It is a schematic explanatory drawing which shows the effect | action of the evaporator of FIG. 3, Comprising: It is a figure showing the cross section of the horizontal direction of an evaporator. It is the schematic which shows another embodiment of the evaporation apparatus of this invention. It is sectional drawing in the B section of FIG. It is a schematic explanatory drawing which shows the effect | action of the evaporation apparatus of FIG. It is the figure which attached the photograph which shows the state of the splash of the vapor | steam to the vicinity of a vapor | steam exit in each evaporator of Example 1 and Comparative Example 1. FIG. It is a graph which shows the quantity of the splash scattered near the evaporation outlet measured using each evaporator of Examples 1-3 and comparative example 1. It is the schematic which shows the conventional evaporator.

  The evaporation apparatus of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic view showing an embodiment of the evaporation apparatus of the present invention. 1 includes a stirring tank 110, a jacket 112 that heats the tank wall 111 of the stirring tank 110, and a spray unit 120.

  The agitation tank 110 is a sealable tank provided with a vapor outlet 113 and is a tank capable of containing and stirring liquids such as aqueous solutions and slurries. The size (capacity) of the stirring tank 110 is not necessarily limited because it can be appropriately set depending on the use of the evaporation apparatus 100 (distillation, precipitation of crystals, concentration of active ingredients, etc.), the amount of liquid to be treated, etc. 0.1 to 80,000 liters. Although the material which comprises the stirring tank 110 is not specifically limited, For example, iron, stainless steel, titanium from the reason that it is stable with respect to various liquids, is excellent in thermal conductivity, and is easy to obtain and process. It is preferably composed of a metal such as hastelloy or copper. The inner wall of the stirring tank 110 may be provided with a coating known in the art, such as Teflon (registered trademark), glass lining, and rubber lining, in order to improve chemical resistance.

  The agitation tank 110 is provided with a jacket 112 for heating the tank wall 111. The jacket 112 is arrange | positioned so that the whole tank wall 111 may be covered from the bottom part of the stirring tank 110, for example. The jacket 112 does not necessarily have to cover the entire tank wall 111 from the bottom of the stirring tank 110. For example, a pipe and a valve (both not shown) capable of appropriately discharging the liquid in the stirring tank 110 are provided at the bottom of the stirring tank 110, and the entire tank wall 111 is removed from the bottom other than those parts. You may cover, or you may cover only the side part of the stirring tank 110 corresponding to the tank wall 111 of the stirring tank 110. The shape and type of the jacket 112 are not particularly limited as long as the tank wall 111 can be heated to a temperature at which the liquid applied to the tank wall 111 is evaporated. Examples of the jacket 112 include a jacket into which high-temperature steam or a heat medium can be introduced. A heat source such as a cable heater may be used instead of or in combination with such a jacket.

  Note that a vapor outlet 113 for recovering vapor generated by heating the liquid is provided in the upper part of the stirring tank 110. Furthermore, the upper part of the stirring tank 110 may also have an openable / closable structure such as a lid or a maintenance hole.

  Inside the agitation tank 110, a sprinkling unit 120 is provided for dispersing the accommodated liquid (that is, a liquid for processing using the evaporator 100) on the tank wall 111 of the agitation tank 110. The spray unit 120 can spray a liquid on the tank wall 111 of the stirring tank 110 and flow down the heated tank wall 110 to form a wet surface on the tank wall 110. The spray unit 120 includes a rotating shaft 121 and a bowl-shaped member 123 attached to the rotating shaft 121.

  The rotating shaft 121 is a shaft made of a metal having rigidity such as iron, stainless steel, hastelloy, titanium, and has a cylindrical shape or a columnar shape, for example. The rotating shaft 121 is normally arranged in the vertical direction in the stirring tank 110. Although the thickness of the rotating shaft 121 is not necessarily limited, For example, it is 8 mm-200 mm. The length of the rotating shaft 121 varies depending on the size of the stirring tank 110 to be used, and an appropriate length can be selected by those skilled in the art.

  One end of the rotating shaft 121 is connected to rotating means such as a motor 140 at the upper part of the stirring tank 110. The other end of the rotating shaft 121 is not connected to the bottom of the stirring tank 110, but is disposed at a position spaced apart from the bottom of the stirring tank 110. The distance from the bottom is preferably set so as to be relatively short (that is, the other end of the rotating shaft 121 extends to the vicinity of the bottom of the stirring tank 110). On the other hand, a bearing (not shown) for steadying the rotation shaft 121 may be provided at the bottom of the stirring tank 110.

In the embodiment shown in FIG. 1, two bowl-shaped members 123 are symmetrically arranged around the rotation shaft 121 constituting the spray unit 120 via the rotation shaft 121. The two hook-shaped members 123 are fixed to the rotating shaft 123 by two fixtures 122 a and 122 b oriented in a direction perpendicular to the rotating shaft 121. Also. In the embodiment shown in FIG. 1, the fixture 122 a is shorter than the fixture 122 b provided on the upper side, and the two bowl-shaped members 123 are arranged on the tank wall 110 side upward with the rotation shaft 121 as the center. angle (also referred to as a mounting angle of inclination) so as to be inclined at theta ₁ fixture 122a, is attached to 122b. Mounting angle of inclination theta ₁ is, for example, 5 ° to 60 °.

  In the evaporation apparatus of the present invention, one or more, preferably 2 to 8, more preferably 2 to 6 bowl-shaped members are attached to the rotating shaft. In the present invention, it is preferable that these hook-shaped members are respectively mounted at substantially equal angles around the rotation axis.

  The bowl-shaped member 123 includes a flow path for flowing the liquid, and can pump up the liquid in the stirring tank 110 from the lower end to the upper end through the rotation of the rotating shaft 121. The bowl-shaped member 123 may have a so-called half pipe shape such as a semi-cylindrical shape, a half-square tube shape, or a V-shape, or the lower end and the upper end have such a harp pipe shape. And the intermediate part between them may be processed into a cylindrical shape. Alternatively, the bowl-shaped member 123 may include a plate-like body 123b in which a part of the semi-cylinder 123a extends along the longitudinal direction as shown in FIG. When the bowl-shaped member 123 shown in FIG. 2 is used, the liquid is drawn from the left side of the paper surface at the lower end of the bowl-shaped member 123 by the rotation of the rotating shaft, and the liquid rises to the upper end of the bowl-shaped member 123 through the rotation. To do. At the time of this rise, the pumped liquid is blocked by the plate-like body 123b even if the bowl-shaped member 123 rotates, and is prevented from jumping out of the bowl-shaped member 123.

  The size of the hook-shaped member 123 is not particularly limited. For example, when a semi-cylindrical hook-shaped member is used, the diameter of the semi-cylindrical portion is, for example, 2 mm to 200 mm. The length from the lower end to the upper end is, for example, 40 mm to 8,000 mm. When the bowl-shaped member has a plate-like body as shown in FIG. 2, the width of the plate-like body is not necessarily limited, but is, for example, 20 mm to 300 mm. The saddle-shaped member 123 is made of a material made of a metal such as iron, stainless steel, hastelloy, titanium, or a combination thereof.

  Referring back to FIG. 1, in the present invention, the spray unit 120 is rotated by a rotating means such as a motor 140, and the liquid in the stirring tank 110 is pumped from the lower end of the bowl-shaped member 123 using the centrifugal force generated by the rotation. The liquid is sprayed from the upper end side of the bowl-shaped member 123 toward the tank wall 111 of the stirring tank 110. Most of the sprayed liquid collides with the tank wall 111 of the stirring tank 110 and flows down the tank wall 111. At that time, the sprayed liquid evaporates due to the heat applied to the tank wall 111 and moves to the evaporation outlet 113 provided above the stirring tank 110.

  In such spraying, according to the present invention, the amount of splash produced by the collision of the liquid with the tank wall in the vicinity of the tip of the bowl-shaped member in the liquid flow direction can be reduced in the stirring tank. Here, in the present specification, “reducing the amount of splash caused by the collision of the liquid with the tank wall in the stirring tank” means that the liquid pumped up from the bowl-like member is sprayed on the tank wall of the stirring tank. When the liquid collides with the tank wall during spraying, it suppresses itself, reduces the amount of substantial splash that diffuses in the stirring tank, and the liquid is sprayed on the tank wall of the stirring tank. This includes both collecting droplets generated by colliding with the wall before being diffused into the agitation tank, and reducing the substantial amount of splashes that diffuse into the agitation tank. In the present invention, this can be achieved by providing a splash reducer in the vicinity of the tip of the bowl-shaped member in the liquid flow direction.

  In one embodiment of the present invention, the splash reducer comprises the following auxiliary saddle member.

  The evaporation apparatus 100 of the present invention shown in FIG. 1 includes an auxiliary hook-shaped member 126 as a splash reducer that extends from the tip of the hook-shaped member 123 in the liquid flow direction. The auxiliary hook-shaped member 126 has an auxiliary flow path through which the liquid passes, and the liquid pumped up from the lower end to the upper end of the hook-shaped member 123 is joined to the joining portion 125 (hereinafter referred to as the hook-shaped member 123 and the auxiliary hook-shaped member 126). , Simply referred to as a joining member 125) and pumped up to the flow path of the auxiliary hook-shaped member 126, and the liquid is sprayed from the distal end portion 124 of the auxiliary hook-shaped member 126 toward the tank wall 111 of the stirring tank 110. Here, in the embodiment shown in FIG. 1, the auxiliary hook-shaped member 126 is bent from the axial direction of the hook-shaped member 123 at the joint portion 125, so that the liquid is transferred from the tip 124 of the auxiliary hook-shaped member 126 to the tank. The ink is discharged in a direction substantially parallel to the wall 111 (that is, above the stirring tank 110). This discharge is performed by weakening the momentum of the liquid pumped from the bowl-shaped member 123 after passing through the joint portion 125. As a result, the discharged liquid can be gently supplied toward the tank wall 111 in the vicinity of the front end portion 124 without jumping out upward of the stirring tank 110. Thereby, the violent collision of the liquid which collides with the tank wall 111 is suppressed, and the quantity of the splash which bounces off the tank wall 111 and can generate | occur | produce can be reduced.

  Alternatively, in the embodiment shown in FIG. 1, the auxiliary hook-shaped member 126 may be bent at the joint portion 125 from the axial direction of the hook-shaped member 123 in a direction substantially parallel to the tank wall 111. By arranging the auxiliary hook-shaped member 126 in this manner, the liquid is gently discharged from the front end portion 124 of the auxiliary hook-shaped member 126, and on the tank wall 111 side near the front end portion 124 rather than above the stirring tank 110. Can be fed towards. For this reason, it is possible to reduce the amount of splashes that bounce off the tank wall 111.

  In the present embodiment, the “direction substantially parallel to the tank wall 111” means not only the direction in which the axis of the auxiliary hook-shaped member 126 is parallel to the plane constituting the tank wall 111 but also the tank. For example, the case where the wall 111 is inclined within the range of −5 ° to + 5 °, preferably within the range of −3 ° to + 3 °, is included.

  Furthermore, it is preferable that the auxiliary hook-shaped member 126 and the tank wall 111 have an appropriate interval so as not to contact each other. The distance of the closest part between the auxiliary hook-shaped member 126 and the tank wall 111 is, for example, 5 mm to 200 mm. When the distance between the adjacent portions is less than 5 mm, when a slight distortion occurs in the rotating shaft during rotation, the tip end portion 124 of the auxiliary hook-shaped member 126 comes into contact with the tank wall 111 and the tank wall 111 or the auxiliary hook There is a risk of damaging the shaped member 126.

  In addition, although the auxiliary hook-shaped member 126 demonstrated the example bent with respect to the hook-shaped member 123 in the junction part 125 in FIG. 1, this invention is not limited only to such a form. Instead of the bending, it may be curved at an arbitrary curvature around the joint portion.

In the present invention, the auxiliary hook-shaped member 126 may have a so-called half-pipe form such as a semi-cylindrical shape, a half-square tube shape, or a V-shape. The length of the auxiliary hook-shaped member 126 (the length from the joint portion 125 to the tip end portion 124) is the rotational speed of the rotating shaft 121; the mounting inclination angle θ ₁ of the hook-shaped member 123, the length and the width; Although it is not necessarily limited because it varies depending on various conditions such as viscosity; for example, it is 10 mm to 200 mm. Furthermore, for example, when a semicylindrical auxiliary hook-shaped member is used, the diameter of the semicylindrical portion is, for example, 10 mm to 250 mm. The auxiliary hook-shaped member 126 is made of a material made of a metal such as iron, stainless steel, hastelloy, titanium, or a combination thereof.

  In the evaporation apparatus 100 of the present invention, the rotation speed of the rotating shaft 121 suitable for pumping up the liquid in the stirring tank 110 (that is, the rotation speed of the spraying section 120) is the viscosity of the liquid, the size of the stirring tank 110, Since it varies depending on the remaining amount of liquid in the agitation tank 110 and the like, it is not necessarily limited, but is, for example, 30 rpm to 500 rpmm.

  FIG. 3 is a schematic view showing another embodiment of the evaporation apparatus of the present invention.

  The evaporation apparatus 200 shown in FIG. 3 includes a stirring tank 210, a tank wall 211, a jacket 212, an evaporation outlet 213, a spraying part 220, a rotating shaft 221, attachments 222a and 222b, a motor 240, and a bowl-shaped member 223. These are the same as those shown in FIG.

  In the evaporation apparatus 200 of the present invention shown in FIG. 3, the splash reducer includes a member that collects splashes generated by colliding with the tank wall, and specifically includes the following plate-like member 230.

  In the evaporation apparatus 200 of the present invention shown in FIG. 3, in the vicinity of the tip 224 of the bowl-shaped member 223 in the liquid flow direction, behind the bowl-shaped member 223 along the bowl-shaped member 223 with respect to the rotation direction of the bowl-shaped member 223. A plate-like member 230 is provided on the side. A plate-like member 230 shown in FIG. 3 has a pentagonal shape in which one apex portion of a rectangle is cut out, and in the radial direction of the rotation shaft 221, the rotation shaft extends from behind the front end portion 224 above the flange-shaped member 223. It extends to the vicinity of 221.

  In the present embodiment, the liquid pumped up from the lower end to the upper end of the bowl-shaped member 223 due to the rotation of the rotating shaft 221 is discharged from the tip 224 of the bowl-shaped member 223 as shown in FIG. The droplets D may collide with 211 and be generated once. However, the generated splash D collides with the plate member 230 that rotates and moves before diffusing into the agitation tank, thereby flowing down the surface of the plate member 230. As a result, the amount of splash finally generated in the stirring tank 210 can be reduced without spreading the splash in the stirring tank 210.

  In the present invention, the size and thickness of the plate-like member 230 are not particularly limited, and it is preferable that the plate-like member 230 is made of a material having rigidity capable of withstanding the rotation of the rotating shaft 221. Examples of the material constituting the plate member 230 include metals such as iron, stainless steel, hastelloy, titanium, and combinations thereof.

  FIG. 5 is a schematic view showing still another embodiment of the evaporation apparatus of the present invention.

  An evaporation apparatus 300 shown in FIG. 5 includes a stirring tank 310, a tank wall 311, a jacket 312, an evaporation outlet 313, a spraying unit 320, a rotating shaft 321, attachments 322a and 322b, a motor 340, and a bowl-shaped member 323. These are the same as those shown in FIG.

  In the evaporation apparatus 300 of the present invention shown in FIG. 5, the splash reducer includes a member that collects splashes generated by colliding with the tank wall, and specifically includes the following second auxiliary hook-shaped member 330.

  In the evaporation apparatus 300 of the present invention shown in FIG. 5, the second auxiliary bowl having a second auxiliary recess disposed so as to cover the flow path of the bowl-shaped member 323 in the vicinity of the tip 324 of the bowl-shaped member 323 in the liquid flow direction. A shaped member 330 is provided. Here, FIG. 6 shows a cross-sectional view of a portion B in FIG. As shown in FIG. 6, the second auxiliary recess 370 provided in the second auxiliary hook-shaped member 330 is opposed to the flow path 374 so as to cover the entire width direction of the flow path 374 of the hook-shaped member 323. Has been placed.

  In the present embodiment, the liquid pumped up from the lower end to the upper end of the bowl-shaped member 323 by the rotation of the rotating shaft 321 is discharged from the tip 324 of the bowl-shaped member 323 as shown in FIG. You may generate | occur | produce the splash D once by colliding with 311. FIG. However, the generated splash D collides with the second auxiliary concave portion of the second auxiliary hook-shaped member 330 before diffusing into the stirring tank, and thereby flows down in the second auxiliary concave portion of the second auxiliary hook-shaped member 330. To do. As a result, the amount of splash finally generated in the stirring tank 310 can be reduced without spreading the splash in the stirring tank 310.

  In the present invention, the second auxiliary hook-shaped member 330 may have a so-called half-pipe form such as a semi-cylindrical shape, a half-square tubular shape, or a V-shape. The length of the second auxiliary hook-shaped member 330 varies depending on various conditions such as the length and width of the hook-shaped member 323; the type and viscosity of the liquid; however, it is not necessarily limited, but is, for example, 2 cm to 30 cm. Furthermore, for example, when the semi-cylindrical second auxiliary hook-shaped member is used, the diameter of the semi-cylindrical portion is, for example, 2 cm to 25 cm. The second auxiliary hook-shaped member 330 is made of a material made of a metal such as iron, stainless steel, hastelloy, titanium, or a combination thereof.

  As described above, in the evaporation apparatus of the present invention, various splash reducers are provided in the vicinity of the tip of the bowl-shaped member in the liquid flow direction. In the above description, for example, in FIGS. 1, 3, and 5, the case where the auxiliary hook-shaped member 126, the plate-like member 230, and the second auxiliary hook-shaped member 330 are independently provided as the splash reducer has been described. As an alternative, two or more of these auxiliary hook-shaped members 126, plate-shaped members 230, and second auxiliary hook-shaped members 330 may be used in combination.

  The evaporation apparatus of the present invention is effective for distillation of liquids such as water, ethanol, thinner, methyl ethyl ketone (MEK), N-methylpyrrolidone (NMP), hexane, toluene, acetone, fats and oils, glycerin, ethylene glycol, and precipitation of crystals. Useful in concentration of ingredients.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not limited to these Examples.

(Comparative Example 1)
In the conventional evaporation apparatus shown in FIG. 10, the amount of splashes scattered near the evaporation outlet was measured as follows.

  First, a sprinkling portion including a rotating shaft and two bowl-shaped members attached to the rotating shaft via attachments is attached to a stirring tank having a capacity of 50 L, and one end of the rotating shaft is used as a motor. Fixed.

The hook-shaped member used is a cylindrical pipe having a diameter of 61 mm and a length of 452 mm cut in half along the length direction. In this comparative example, the two hook-shaped members are symmetrical about the rotation axis. And the concave side of the pipe was arranged in the direction of the rotation axis. The mounting inclination angle θ ₁ of the bowl-shaped member was 13.3 °, and the horizontal distance from the rotation axis at the upper end of the bowl-shaped member (corresponding to the rotation radius) was 190 mm. The stirring tank was provided with an upper lid, and an evaporation outlet was provided in a part of the upper lid. A jacket was attached to the outer wall surface of the stirring tank, and steam was supplied to the jacket. Furthermore, the jacket was covered with a heat insulating material.

  Next, 38 × 52 mm square water sensitive paper was installed at the steam outlet in the stirring tank, and 7 L of tap water (water temperature 20 ° C. to 26 ° C.) was charged into the stirring tank. The height of the liquid level was about 83 mm from the bottom of the stirring tank. From this state, tap water in the stirring tank was sprinkled on the tank wall by rotating the spraying part at a predetermined rotation speed. The measurement time was 10 seconds to 4 minutes, and was changed according to the amount of splash. At this time, the amount of droplets accompanying actual stirring was measured at room temperature without heating this time, not the droplets accompanying evaporation.

  FIG. 8 shows the result of receiving splashes with water-sensitive paper provided at the steam outlet under the conditions of the number of revolutions of the spraying portion of 185 rpm for 1 minute, 195 rpm for 30 seconds, and 205 rpm for 10 seconds.

  As shown in FIG. 8, in the evaporation apparatus of this comparative example, in the test when rotated at 185 rpm for 1 minute, a droplet with large particles was observed, and at 195 rpm, the rotation was performed at 185 rpm for 1 minute at 30 seconds. It can be seen that droplets having a higher density than those in the test were observed, and that more droplets were observed at 205 rpm for 10 seconds.

The obtained photograph was read with a scanner, and the obtained data was binarized (threshold: 50%), and the number of spots displayed on the obtained image and the diameter of each spot were measured. From the number of stains obtained and the diameter of each stain, the area (mm ² ) of the stain is calculated, and each droplet (particle) is calculated according to the following formula based on the diffusion coefficient described in the instruction manual of the water sensitive paper. The diameter (mm) of was calculated:

  The volume of each droplet was calculated based on the diameter of the obtained droplet particles, and the obtained volumes were integrated to obtain the amount of droplets (water) received by the water sensitive paper. The value of the obtained amount (the amount of water per area of the water sensitive paper) was converted to the amount per opening area of the steam outlet, and the amount of splashes scattered at the steam outlet was calculated. FIG. 9 shows the relationship between the amount of droplets and the number of rotations of the sprayed part.

Example 1
Except that the evaporation apparatus shown in FIG. 1 was used, tap water in the agitation tank was ejected in the same manner as in Comparative Example 1, and the amount of splashes scattered near the evaporation outlet was measured. The obtained results are shown in FIGS.

  In addition, among the splash reducers used in the present embodiment, the auxiliary bowl-shaped member is a cylinder pipe having a length of 80 mm, which is cut in half along the length direction, and the tank wall. And welded to the tip portion of the bowl-shaped member so as to be substantially parallel to each other.

  As shown in FIG. 8, the evaporation apparatus of Example 1 had a smaller amount of splashes scattered on the water-sensitive paper even when rotated at 185 rpm for 2 minutes as compared with the case of using the apparatus of Comparative Example 1. I understand that. Moreover, even when it was rotated for 2 minutes at 195 rpm, the amount of splashes was small compared with the case of being rotated for 30 seconds in Comparative Example 1. Furthermore, even when each was rotated at 205 rpm, 215 rpm, and 225 rpm for 1 minute, the amount of droplets was small compared to the case of rotating at 205 rpm in Comparative Example 1 for only 10 seconds. From this, it can be seen that, in the evaporation apparatus of Example 1, the amount of droplets scattered near the evaporation outlet is significantly reduced as compared with the evaporation apparatus of Comparative Example 1.

(Example 2)
Except having used the evaporator shown in FIG. 3, the tap water in a stirring tank was spouted similarly to the comparative example 1, and the amount of the splash scattered in the evaporation outlet vicinity was measured. The obtained results are shown in FIG.

  Of the splash reducers used in this example, the plate-like member has one apex portion so that a rectangular stainless steel plate having a width of 135 mm, a height of 240 mm, and a thickness of 3 mm can be accommodated in the stirring tank. And has a pentagonal shape with a notch cut out, and is disposed behind the hook-shaped member with respect to the rotation direction of the hook-shaped member so as to be substantially perpendicular to the rotation direction of the hook-shaped member. The evaporation apparatus used in this example was the same as that used in Comparative Example 1 except that.

(Example 3)
Except that the evaporator shown in FIG. 5 was used, tap water in the agitation tank was ejected in the same manner as in Comparative Example 1, and the amount of splashes scattered near the evaporation outlet was measured. The obtained results are shown in FIG.

  Of the splash reducers used in this example, the second auxiliary hook-shaped member is a cylindrical pipe having a width of 150 mm and a length of 285 mm cut in half along the length direction. In parallel, the upper side of 175 mm was projected from the upper end of the hook-shaped member, and the second auxiliary recess of the second auxiliary hook-shaped member was arranged to face the flow path of the hook-shaped member. The evaporation apparatus used in this example was the same as that used in Comparative Example 1 except that.

  As shown in FIG. 9, in the evaporation apparatus of Comparative Example 1, the amount of splashes scattered near the evaporation outlet increases due to the increase in the rotation speed from the relatively low rotation speed stage. It can be seen that it could be observed from the stage. On the other hand, in each of the evaporators of Examples 1 to 3, the amount of splashes scattered near the evaporation outlet could be remarkably reduced as compared with the evaporator of Comparative Example 1. In particular, in the evaporation apparatus of Example 1, splashing of splashes can be suppressed even at a rotation speed exceeding 200 rpm, compared to the apparatus of Comparative Example 1, and operation at a higher rotation speed is possible, and the efficiency as an evaporation apparatus is improved. It can be seen that it has increased further.

100, 200, 300 Evaporator 110, 210, 310 Stirring tank 111, 211, 311 Tank wall 112, 212, 312 Jacket 113, 213, 313 Steam outlet 120, 220, 320 Sprinkling part 121, 221 and 321 Rotating shaft 123 223, 323 bowl-shaped member 125 joint portion 126 auxiliary bowl-shaped member 140, 240, 340 motor 230 plate-like member 330 second auxiliary bowl-shaped member

Claims (2)

An evaporating apparatus comprising: a sealable stirring tank provided with a steam outlet; a jacket for heating the tank wall of the stirring tank; and a spraying part for spraying a liquid onto the tank wall of the stirring tank,
here,
The liquid dispersion part is composed of a rotating shaft and one or more bowl-shaped members having a flow path for flowing the liquid and attached to the rotating shaft; and the liquid of the bowl-shaped member In the vicinity of the tip in the flow direction, a plate-like member is provided that reduces the amount of splash produced when the liquid collides with the tank wall in the stirring tank .
The plate-like member is located behind the hook-like member with respect to the rotation direction of the hook-like member and from the back of the distal end portion above the hook-like member along the radial direction of the rotary shaft. An evaporator that extends to the vicinity . The evaporator according to claim 1 , wherein the plate-like member is provided so as to be substantially perpendicular to a rotation direction of the bowl-like member.

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