JP3070163B2 - Centrifugal sprayer for spray drying equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary disk type spraying device, and more particularly to a centrifugal spraying device for a spray drying device capable of achieving a required effect of energy saving.

[0002]

2. Description of the Related Art Conventionally, a stock solution to be dried is sprayed at a high pressure onto a surface of a rotating disk which is driven at a high speed by a centrifugal sprayer provided at a central portion of a ceiling of a drying chamber, and is scattered in high temperature air for drying. A rotating disk type spray drying apparatus having a structure for drying to dryness is used. That is, as shown in FIG. 7, this type of centrifugal sprayer supplies a liquid raw material supply pipe 53, which is opened to a pocket 52 of a spray rotating disk 51, which is mounted on a rotating shaft 50, from a pump (not shown). The raw material solution to be dried is supplied, and the rotating shaft 50 is rotated at high speed, and the raw material solution to be dried is directly supplied in one stroke through a large number of spray holes 54, 54. It is a centrifugal spray method that sprays water.

[0003] Originally, the quality of the dried product obtained by this type of spray dryer, except for special ones, is about 97%.
% Is irrelevant to the shape of the spray disk 51 and mostly depends on the peripheral speed of the rotating disk. The peripheral speed of the rotating disk 51 which is generally used most often is about 90 m.
For example, in the case of a ramen soup (name of a stock solution to be dried), the concentration is 40%, the liquid specific gravity is 1.1, and the liquid temperature is 60.
° C and a stock solution processing capacity of 1,000 kg / hour, the diameter of the rotating disk 51 is 180 mm and the number of rotations is 10,000 r.
p. m. , The peripheral speed becomes 90 m / sec, and the required horsepower of the motor driving the rotating shaft 50 at this time is 11 Kw. And, under the above conditions, the processing capacity of the undiluted solution is 5,000K.
In g / hour, the required horsepower of the motor amounts to 22 Kw.

[0004] As described above, this type of centrifugal sprayer is required to operate at a high speed, and therefore has the disadvantage that the power consumption is extremely large.

In a conventional spray dryer, the rotating disk 5
Since the rotating shaft 50 for rotating the rotating disk 1 is located at the center of the rotating disk 51, the installation position of the raw liquid supply pipe 53 to be dried must be provided at a position deviated from the rotating center. There was a problem that the contact radius with the contact member 51 became short and the drying efficiency was poor.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and enables a low-speed rotary spray without lowering the drying processing capacity from a conventional high-speed rotary spray system, and also provides a centrifugal spray. It is an object of the present invention to provide a centrifugal sprayer for a spray-drying device that can reduce the required power of the sprayer and achieve energy saving.

[0007]

According to the present invention, there is provided a centrifugal sprayer for a spray drying apparatus for supplying a stock solution to be dried in a high-temperature dry air atmosphere for drying. A secondary spraying disk having a number of secondary spraying holes formed in a peripheral wall thereof in a dry air atmosphere is axially provided so as to be rotationally driven at an appropriate peripheral speed by an external rotary driving device,
Constituting primary spraying means for generating a primary mist of the raw liquid to be dried toward the secondary spray hole on the inner diameter side of the secondary spraying disk,
Supplying the undiluted solution to the primary spraying means while rotating and driving the secondary spraying disc, and drying the secondary mist of the undiluted solution discharged from the secondary spray holes of the secondary spraying means. Is what you do.

[0008] The primary spray means is a spray nozzle,
Alternatively, it can be realized by a primary spraying disk, and the primary spraying means is preferably arranged concentrically with the secondary spraying disk.

[0009]

The centrifugal sprayer for a spray-drying apparatus having the above-described structure rotates a secondary spraying disc having a large number of secondary spraying holes in a peripheral wall thereof while rotating a primary spraying nozzle or a primary spraying nozzle formed on an inner diameter side thereof. The primary mist of the stock solution to be dried is ejected from the working disk toward the secondary spray hole. Therefore, when the primary mist passes through the secondary spray holes that are rotationally displaced at an appropriate peripheral speed by centrifugal action, the primary mist becomes a secondary mist having an ultrafine particle diameter, and is released into a high-temperature dry air atmosphere. Momentary heat is exchanged instantaneously to evaporate water, and the stock solution is dried and powdered.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a centrifugal sprayer for a spray dryer according to the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show a first embodiment. As shown in FIG. 3, a centrifugal sprayer 1 according to the present invention is connected to an upper edge of an inverted conical hopper 3 constituting a drying chamber. An annular hot air blowing device 4 fixed to the upper wall 2a so as to be positioned on the center axis CL of the cylindrical portion 2 formed on the lower surface of the upper wall.
The annular hot air blowing port of the hot air blowing device 4 and the secondary spraying portion of the centrifugal sprayer 1 are provided on the lower side in the annular shape. A hot gas supply port 5 for drying is opened on one side of the hot air blowing device 4, and an exhaust pipe connected to the outside of the drying chamber is provided above a discharge port 6 formed at the lower end of the hopper 3. 7 opened.

The centrifugal sprayer 1 is connected to a bottomed cylindrical main body 8 having an end plate 11 fixed at an upper end thereof via upper and lower bearings 12, 12 pivotally mounted on the end plate 11 and a support bracket 13. A rotary tube shaft 9 is rotatably inserted through the shaft center position, and a pulley 26 is mounted on the upper end of the rotary tube shaft 9.
And a pulley 27 pivotally connected to an external rotary drive device such as a secondary disk drive motor 28 via an endless belt. An oil seal 24 is formed outside the upper bearing 12, and the bearing 12 and the oil seal 2 are formed.
The rotary pipe shaft 9 is rotatably sealed with a seal oil pressure supplied from an oil supply port 20 opened between the four bearings 4, and a bottom wall of the bottomed cylindrical main body 8 is provided outside the lower bearing 12. Edge 1 extrapolated to the draining collar 15 projecting from
An oil drain nut 14 having a nut 4a is fastened, and the oil drain nut 14 rotates cooperatively with the rotary pipe shaft 9 to seal the shaft. The bore of the bottomed cylindrical body 8 forms an oil reservoir 16, and the oil suction pipe 21 is inserted from near the lower end of the oil reservoir 16 to the outside of the bottomed cylindrical body 8 via the end plate 11. It becomes.

Reference numeral 19 designates a hollow disk-shaped secondary spray disk which is mounted on the lower end of the rotary tube shaft 9 and which is used for the spray disk body 1.
The upper surface of 9a is covered with a cover disk 19b, the rotary pipe shaft 9 is opened to the inner cavity, and a number of secondary spray holes 19c, 19c,... I will set it up. In the inner cavity of the secondary spray disk 19, the lower end of the liquid material supply inner tube 10 inserted from the upper end of the rotary tube shaft 9 to the center of the shaft is opened.

Reference numeral 18 denotes a primary spray nozzle head screwed and fixed to the lower end of the liquid material supply inner pipe 10, and a plurality of primary spray nozzles 17 protruding from the primary spray nozzle head 18 in the horizontal direction. Are connected to the inner pipe 10 for supplying the liquid material.

Reference numeral 22 denotes an O-ring for sealing, and 29 denotes a continuously variable transmission controller for controlling the rotation speed of the secondary disk drive motor 28.

The centrifugal sprayer 1 having the above-described structure supplies the seal oil from the oil supply port 20 and discharges and circulates the seal oil retained in the oil sump 16 through the oil suction pipe 21 so as to circulate the upper and lower bearings 12. , 12 while supplying the stock solution to be dried from the liquid material supply inner tube 10 while rotating the rotary tube shaft 9 at a predetermined rotation speed via the pulleys 26 and 27 by the secondary disk drive motor 28. Things.

At this time, from the hot-air blowing device 4 provided at the upper end of the drying chamber 2, the dried high-temperature gas is blown toward the vicinity of the secondary spraying disc 19. Are mixed with the atomized liquid particles ejected from the secondary spray holes 19c, and are instantaneously exchanged with the high-temperature gas body to evaporate the water, whereby the undiluted solution is dried and powdered.

The primary spray nozzles 17, 17,...
The droplets ejected from the nozzle form an ideal spray structure that can be linearly supplied to the secondary spray holes 19c of the secondary spray disk 19 located immediately before the primary spray. When the primary mist formed by the nozzle 17 passes through the secondary spray hole 19c, it forms a secondary mist having a finer particle size, and is combined with the centrifugal spray action by the rotation of the secondary spray disk 19. As a result, a secondary mist having an ultrafine particle size can be obtained.

Next, FIGS. 4 and 5 show a second embodiment of the present invention. The structure different from that of the first embodiment will be described. The inner tube for supplying a liquid material denoted by reference numeral 10 forms a concentric rotating shaft rotatably inserted through the rotating tube shaft 9 via the oil-containing metals 31, 31. The upper end is rotatably connected to a raw material supply pipe (not shown) via a rotary joint 30. The inner pipe 10 for supplying the liquid material is rotatably connected by an endless belt between a pulley 32 attached to the vicinity of the upper end and a pulley 34 attached to the primary disk drive motor 33 by an endless belt. The rotation speed of the primary disk drive motor 33 is controlled. At the lower end of the inner pipe 10 for supplying liquid material, a disk 47 for primary spraying is fixed, and is located in the inner cavity of the disk 19 for secondary spraying so as to be freely rotatable. The primary spray holes 47a, 47a,..., Which are formed in the peripheral wall of the disk 47 and communicate with the liquid material supply inner pipe 10, respectively, are at the same level as the secondary spray holes 19c of the secondary spray disk 19. Arrange them.

In the second embodiment, the secondary disk drive motor 28 is driven to rotate the secondary spray disk 19 while simultaneously driving the primary disk drive motor 33 to rotate the rotary pipe joint 30.
The raw material to be dried is supplied to the inner pipe 10 for supplying the liquid raw material via the liquid supply. At this time, the secondary disk drive motor 28 and the primary disk drive motor 33 are driven to rotate so that the secondary spray disk 19 and the primary spray disk 47 rotate in opposite directions.

The stock solution to be dried supplied to the rotating primary spraying disk 47 via the liquid material supply inner pipe 10 is radially discharged from a number of primary spraying holes 47a, 47a, and is centrifugally acted upon. Forms a fog. At this time, on the outer side of the primary spraying disk 47, a large number of secondary spraying holes 19c formed in the secondary spraying disk 19 rotating in the opposite direction.
19c are opposed to each other, the primary mist is further centrifugally sprayed when passing through the secondary spray hole 19c, and the relative speed of the two spray disks 19, 49 is increased. The next fog is formed. Then, the secondary mist comes into contact with the high-temperature gas jetted from the hot-air jetting device 4 and instantaneously exchanges heat, evaporating water to dry powder.

According to the present invention, the secondary spray disk 19
In order to achieve the object of the invention by forming a primary spraying means on the inner diameter side of the secondary spraying hole 19c formed in the secondary spraying hole 19c, as shown in FIG.
Rotating shaft 36 instead of rotating tube shaft 9
The lower end of the spray disk body 19a
Liquid source supply pipe 3 provided with primary spray nozzle 37 at 9d
8 and the primary spray nozzle 37 is connected to the primary spray holes 19c,
19c...

[0023]

As described above, according to the structure of the centrifugal sprayer for the spray drying apparatus according to the present invention, the secondary mist is further subjected to the secondary mist by the centrifugal action of the secondary mist disk formed in front of the primary mist. By adopting the double spray structure for forming the mist, the particle diameter of the stock solution to be dried that comes into contact with the high-temperature gas can be made ultra-fine, and the drying treatment can be performed efficiently. Further, according to the configuration of the present invention, since the supply position of the liquid to be treated to the secondary spraying disk is located at the center of rotation, the secondary spraying disk acts ideally for centrifugal spraying. Therefore, the centrifugal sprayer of the present invention can be implemented even if the rotation speed of the secondary spraying disk is relatively low, and the rotation speed of the rotation drive motor can be reduced. It is possible to reduce the size of the device at the same time as saving energy. Furthermore, it has features such as improving the work environment because noise during device operation can be reduced with low-speed operation,
The effect after implementing the present invention is extremely large.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a centrifugal sprayer according to the present invention.

FIG. 2 is an enlarged sectional view of a main part of the centrifugal sprayer.

FIG. 3 is a schematic vertical sectional view of a spray drying device provided with the centrifugal sprayer.

FIG. 4 is a longitudinal sectional view showing a second embodiment of the centrifugal sprayer according to the present invention.

FIG. 5 is an enlarged sectional view of a main part of the centrifugal sprayer.

FIG. 6 is an enlarged sectional view of a main part showing a third embodiment of the centrifugal sprayer according to the present invention.

FIG. 7 is an enlarged sectional view showing a main part of a conventional centrifugal sprayer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Centrifugal sprayer 4 Hot-air jetting device 8 Cylindrical main body with a bottom 9 Rotating pipe shaft 10 Inner pipe for liquid raw material supply 15 Draining collar 16 Oil drain nut 17 Primary spray nozzle 18 Primary spray nozzle head 19 Secondary spray disk 19c 2 Next spray hole 24 Oil seal 28 Secondary disk drive motor 30 Rotary fitting 33 Primary disk drive motor 36 Rotating shaft 37 Primary spray nozzle 38 Liquid material supply pipe 47 Primary spray disk 47a Primary spray hole

Claims (4)

(57) [Claims] 1. A centrifugal sprayer for a spray-drying device for supplying a stock solution to be dried in a high-temperature dry air atmosphere and performing a drying process, wherein a number of secondary spray holes are formed in a peripheral wall in the high-temperature dry air atmosphere. The disk for secondary spraying is rotatably driven at an appropriate peripheral speed by an external rotary driving device, and the primary mist of the raw liquid to be dried toward the secondary spray hole is provided on the inner diameter side of the disk for secondary spraying. The secondary spraying means is configured to supply the raw liquid to be dried to the primary spraying means while rotating and rotating the secondary spraying disc, and to dry the raw liquid to be dried discharged from the secondary spraying holes of the secondary spraying means. A centrifugal sprayer for a spray-drying device, characterized by drying the next mist. 2. The primary spraying means is a spray nozzle,
2. The centrifuge for a spray-drying apparatus according to claim 1, wherein the liquid to be dried is fed by an external pressure feeding means from a liquid raw material supply pipe communicating with the spray nozzle, and the primary mist is sprayed toward a secondary spray hole. Sprayer. 3. A liquid source supply pipe communicating with said primary spraying means is provided so as to penetrate through the axis of a rotary pipe shaft on which a secondary spraying disc is provided, and a spray nozzle is connected to said secondary spraying disc. 3. The centrifugal sprayer for a spray dryer according to claim 2, wherein the centrifugal sprayer is arranged at a concentric position. 4. The primary spraying means is a primary spraying disk in which a number of primary spraying holes are formed in a peripheral wall axially provided on a concentric center of a bore of a secondary spraying disk, and the primary spraying disk is rotated. The inner pipe for liquid raw material supply, which is movably mounted and feeds the liquid to be dried, is inserted through the axis of a rotary pipe shaft provided with a disk for secondary spraying, and the first spray bewitching disk is mounted. 2. The centrifugal sprayer for a spray drying apparatus according to claim 1, wherein the centrifugal sprayer is configured to be rotationally driven by an external rotary driving device via the liquid material supply inner pipe.