JPH03213101A - Centrifugal spraying apparatus for spray dryer - Google Patents

Abstract

PURPOSE:To improve drying efficiency as well as energy efficiency by projecting a plurality of propeller blades for spraying evenly and radiately in the lower and of a freely rotatable hollow shaft, connecting each blade with a raw liquid supplying pipe axis, and forming a raw liquid supplying pipe line on the upper end of the raw liquid supplying pipe axis. CONSTITUTION:In a centrifugal spraying apparatus for a spray dryer wherein a raw liquid to be dried is sprayed and supplied to dry air atmosphere to be dried, a hollow shaft 16 which is freely rotated by an outside rotating system is installed. A plurality of propeller blades 22 are projected evenly and radiately in a direction with a proper angle against propeller blades installation seats 21 fixed in the lower end of the hollow shaft 16 and each blade is connected with raw liquid supplying pipe axis 16. A raw liquid supplying pipe line 27 is formed through a rotary pipe joint 25 installed in the upper end of the raw liquid supplying pipe axis 16. As a result, drying efficiency and energy efficiency are improved and, at the same time, the apparatus is made compact.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement of a rotating disk type spray drying device, and relates to a centrifugal sprayer for a spray drying device that can achieve high efficiency and miniaturization. be.

[Conventional technology] Conventionally, the stock solution to be dried is sprayed at high pressure onto the surface of a rotating disk driven at a small speed by a centrifugal sprayer installed in the center of the ceiling of a drying room, and then dispersed into the high-temperature drying air. Moment 4I! ,
A rotating disk type spray drying device with a drying structure is used. And this centrifugal sprayer.

Since the axis that rotates the rotating disk is located at the center of the rotating disk, the spray nozzle for the stock solution must be placed away from the axis, which shortens the radius of contact with the rotating disk and reduces drying efficiency. I had a problem.

Originally, about 97% of the quality of dried products obtained with this type of spray dryer is unrelated to the shape of the jet disk, except for special ones, and is mostly determined by the circumferential speed of the rotating disk. . -The circumferential speed of the rotating disk most commonly used in boat fishing is approximately 70 m/sec, and for example, the undiluted solution processing capacity is 1.0 m/sec.
In the case of a 00 kg/hour spray %l dryer, the diameter of the rotating disk is 2001 mψ, and the number of rotations is 11. At OOOrpm, the speed of one circumference is 70 rn/sec, and the required motor horsepower at this time is IIKW.

Furthermore, with conventional rotating disks, it is technically difficult to make the spray angle narrower than 170 degrees, so in order to ensure the flight distance of the spray droplets generated by the rotating disk, the diameter of the drying chamber must be increased, and the equipment had the problem of increasing in size.

C9! [Problems to be Solved by Akira] The present invention has been made in view of the above problems, and aims to improve the drying efficiency of the apparatus as well as the energy efficiency. Another purpose is to realize a J\ type of device.

[Means for Solving the Problems] A centrifugal sprayer for a spray dryer 4 according to the present invention is a centrifugal sprayer for a spray dryer that sprays and supplies a stock solution to be dried into a drying air atmosphere. +! A hollow shaft that can be freely rotated by an II mechanism is installed, and a plurality of injection propeller blades are radially equally spaced and project from a propeller blade mounting seat fixed to the lower end of the hollow shaft in an appropriate angular direction, Each communicates with the DOT liquid supply pipe shaft, and the DOT liquid supply pipe shaft
The gist of this is that the stock solution supply conduit is formed via an l1jl dynamic pipe joint provided at one end.

Preferably, in the above structure, a spray nozzle member is provided at each injection propeller blade tip protruding from the propeller blade mounting seat.

Further, each of the injection propeller blades protruding from the propeller blade mounting seat is configured such that the protruding angle with respect to the central axis can be freely adjusted.

[Operation] A dryer with a centrifugal sprayer configured as described above supplies the liquid to be dried while rotating the stock solution supply tube shaft at a predetermined rotational speed by a rotation drive device such as an external motor, and supplies the liquid to be dried at the upper end of the drying chamber. The atomized stock solution is jetted from the tip of the propeller blade and mixed into the dry high-temperature gas atmosphere spouted from the installed hot air blowing device, and instantaneous heat exchange is performed to evaporate water and dry and powder the stock solution. .

[Embodiment Example] An embodiment of a centrifugal sprayer for a spray drying apparatus according to the present invention will be described in accordance with the first example to FIG. 3.

As shown in FIG. 3, the centrifugal jet machine 1 of the present invention has a drying chamber 2
An annular hot air blowing device 5 is fixedly attached to the upper wall 4 so as to be located on the central axis of the cylindrical portion 4 continuous to the upper edge of the inverted conical hopper 3, and formed on the lower surface of the upper wall 4. A drying gas supply boat 6 is opened on one side of the hot air blowing device 5, and a drying gas supply boat 6 is opened on one side of the hot air blowing device 5. An exhaust pipe 8 that communicates with the outside of the drying chamber is provided.

The centrifugal jet V1 machine 1 has a cylindrical body frame 12 with a mount plate 11 fixedly attached to its upper end, and a bearing 14-. A stock solution supply pipe + jill Il 6 is rotatably installed via a shaft 15, and an external rotation drive device such as a motor (not shown) is attached to the upper end.
A pulley 24 rotatably connected to the upper bearing 14 is pivotally mounted, and the oil supply boat 17 is opened between the upper bearing 14 and an oil seal 14a provided on the outside thereof. Further, an oil nut 19 having a cut edge that fits over a collar edge 18 protruding from the bottom wall of the main body frame 12 is fastened to the lower bearing 15, and rotates in cooperation with the stock solution supply pipe shaft 16. In addition, an oil suction pipe 20 is provided which communicates with the vicinity of the lower end of the oil reservoir 29 in the inner cavity of the main body frame 12 via the mount plate 1-11. Reference numeral 21 denotes a propeller blade mounting seat fixed to the lower end of the stock solution supply pipe shaft 16, and the propeller blade mounting seat 21 has an 8 projecting in a direction of about 45 degrees in longitudinal section.
Injection propellers g22, 22... are equally distributed radially with respect to the shaft, screwed into and protruding from screw holes 23, 23..., and communicated with the stock solution supply pipe shaft 16, respectively. Rotary pipe joint 25 provided at the upper end of the stock solution supply pipe shaft 16
A stock solution supply path 27 is formed through the stock solution supply port 26 of.

If pressurized spray is required in addition to rotary spray, a nozzle member 28 having a small-diameter nozzle hole 30 is installed at the tip of each propeller blade 22 arranged on the propeller mounting seat 21, as shown in FIG. Use by connecting with screws.

The centrifugal sprayer 1 configured as described above has upper and lower bearings 1.
4. To maintain normal bearing function of 15.

Oil is supplied from [111 boat] 7, and oil is supplied from oil sump 2.
While the oil accumulated in the tube 9 is discharged and circulated through the oil suction pipe 20, the stock solution supply pipe shaft 16 is rotated at a predetermined rotational speed via the pulley 24 by a rotational drive device such as an external motor. At the same time, the liquid to be dried is supplied from the stock liquid supply port 26. At this time, dry high-temperature gas is ejected from the hot air blowing device 5 provided at the upper end of the IK drying chamber 2 toward the vicinity of the propeller blades 22, and the propeller X
It mixes with the atomized stock solution spouted from 22, instantaneous heat exchange takes place, water evaporates, and - the stock solution becomes dry and powdered.

According to the above configuration, by setting the rotation axis of the centrifugal sprayer to the stock solution supply pipe shaft 16, the stock solution can be supplied from the central axis position of the sprayer 1, thereby creating an ideal spray structure. In addition, since the pipe for introducing the stock solution is omitted, the device can be simplified.

[Centrifugal sprayer with the above configuration] If the length of the injection propeller . Therefore, there is no need to rotate the stock solution supply pipe shaft 16 at an extremely high speed, and it rotates at a low speed (the rotation speed of the 2P motor).
This makes spraying possible, and at the same time the weight of the main body of the sprayer is reduced, and at the same time, the horsepower required for the motor that rotates the sprayer is only about 1/3 smaller than that of the conventional structure. Furthermore, as the rotational speed decreases, the rotational noise during operation also decreases.

According to the above configuration, the spray angle of the droplets can be arbitrarily and easily changed by changing the mounting angle of the propeller blades 22, so the diameter of the drying chamber 2 can be designed to be small, and the drying device The entire structure can be downsized.

As shown in FIG. 4, a nozzle member 28 having a spray nozzle 30 is attached to the tip of the propeller By pressurizing the liquid at a pressure of /amG, the undiluted liquid is temporarily sprayed from the nozzle member 28 provided at the tip of the injection propeller blade 22, and droplets of the pressurized spray are ejected with a linear trajectory. However, since the propeller blades 22 are rotating, the trajectory of the droplets ejected from the nozzle member 28 begins to turn in a curved line, and the flight distance until they hit the wall of the drying chamber 2 becomes longer. Even if the diameter of the drying chamber 2 is made small, a sufficient flight distance required for heat exchange can be obtained.

In addition, in the above configuration, the rotation of the large number of injection propeller blades 22 causes the drying air in the inner cavity of the drying chamber 2 to be violently stirred and vibrated, causing sufficient contact (heat exchange) between the droplets and the hot air, which are scattered in the form of mist. As a result, the thermal efficiency of the device can be improved.

[Effects of the Invention] As described above, according to the configuration of the centrifugal sprayer for spray drying equipment according to the present invention, there are advantages that could not be achieved with the conventional technology. The dripping position of the supplied stock solution.

This provides an ideal location for spraying, eliminates the need to install a liquid delivery pipe, and simplifies the structure for convenient handling.

(2) The injection propeller blade structure, which replaces the conventional rotating disk, rotates at a speed 1/3 slower than the conventional structure, making it possible to reduce the driving power and the noise generated.

(3) Also, the injection angle can be arbitrarily narrowed depending on the structure of the injection propeller blade. Therefore, the diameter of the drying chamber can be reduced to about 1/2 compared to the conventional one.

(4) Since it is a double spray system that combines pressurized spray and rotary spray, the purpose can be achieved by supplying the stock solution at a low pressure and rotating the stock solution supply pipe shaft at a low speed.

(5) As the propeller blades installed on the rotating disk continue to violently vibrate and stir the drying air, the heat exchange area increases due to the contact between the sprayed droplets and the hot air, which improves thermal efficiency. can be significantly improved.

Therefore, the effects after implementation of the present invention are extremely large.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a centrifugal sprayer for a spray dryer according to the present invention, FIG. 2 is a bottom view of the same, and FIG. 3 is a schematic sectional view showing the state installed in a dryer. FIG. 4 is a cross-sectional view of the propeller blade tip showing a state in which a spray nozzle is provided. DESCRIPTION OF SYMBOLS 1...Centrifugal injection machine, 2...Drying room, 5...Hot air blowing device, 6...Gas supply port, 7...Discharge port, 8
...Exhaust pipe, 12...Body frame, 14.15.
... Bearing, 16... Stock solution supply pipe shaft, 21...
Propeller blade mounting seat, 22... Propeller blade for injection, 25
... Rotating pipe joint, 26 ... Stock solution supply boat, 27.
... Raw solution supply path, 28... Nozzle member. 1.-Centrifugal jet 11a, 2 rL explosion chamber, 5. Outside air jet device, 6. Gas supply boat, 7. Wandering 11 explosion 8. Exhaust!
, 12・Body frame L4. Ifi bearing,
16 Stock solution supply pipe shaft, 21 Buura blade claw (=1 seat, 2
2. Injection propeller blade, 25-1tJ! Fll pipe fitting 26 Stock solution supply port, 27-11 contact supply path, 28-
Nozzle parts. Figure 2 Figure 2 Procedure auxiliary equipment (voluntary) February 20, 1990

Claims (3)

[Claims] (1) In a centrifugal sprayer for a spray dryer that sprays and supplies a drying stock solution into a dry air atmosphere and dries it, a hollow shaft that can be freely rotated by an external rotation drive mechanism is installed, and the lower end of the hollow shaft is fixed. A plurality of propeller blades for injection are arranged radially and equidistantly protruding from the propeller blade mounting seat provided in an appropriate angular direction,
A centrifugal sprayer for a spray drying apparatus, each of which is in communication with a stock solution supply pipe shaft, and a stock solution supply pipe line is formed via a rotary pipe joint provided at the upper end of the stock solution supply pipe shaft. (2) The centrifugal sprayer for a spray dryer according to claim 1, wherein a spray nozzle member is provided at each injection propeller blade tip protruding from the propeller blade mounting seat. (3) The centrifugal sprayer for a spray drying device according to claim 1 or 2, wherein each of the injection propeller blades protruding from the propeller blade mounting seat is adjustable in protrusion angle.