JPS60205169A - Continuous treater for drying, etc. - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous processing apparatus for drying, etc. suitable for drying water-containing materials containing harmful substances such as radioactive waste.

Treatment of hydrated materials such as concentration, dehydration, drying, incineration, melting, solidification, etc. in order to reduce the volume of hydrated materials containing harmful substances, such as concentrated waste liquids containing radioactive waste, sludge, and sludge, and make them into stable assimilated substances. Research and development of technology has been actively conducted in recent years, and some of it has already been put into practical use.

By the way, when dehydrating and drying a water-containing material containing harmful substances as described above, it is desirable to prevent non-volatile harmful substances from scattering as dust and mixing into exhaust gas as much as possible. However, in continuous processing equipment such as thin film dryers and rotary kilns that are commonly used for dehydration and drying of water-containing materials, since the water-containing materials are stirred within the equipment, the scattering of dry dust is unavoidable. cannot prevent the mixture from entering the exhaust gas. Therefore, it was necessary to attach a separation and collection device for this dust to the exhaust gas treatment device. In addition, there are vacuum freeze dryers and externally heated stirring tanks for batch-type processing #cm, but the former requires a large surface area and does not have a high fL, and there is a risk that the dried materials will scatter when moving or transferring. However, in the latter case, dust scattering due to stirring becomes a problem, similar to the above-mentioned continuous processing apparatus.

Therefore, as an alternative to the conventional general processing apparatus described above, for example, a coaxial microwave drying apparatus as shown in FIG. 2 has been devised. This drying device consists of a metal cylindrical body 1 and a rotating shaft 3 equipped with a screw blade 2 formed of a dielectric material, and the microwave is guided into the cylindrical body from a microwave inlet 4 to an input port. The water-containing material introduced from 5 is dielectrically heated and discharged from an outlet 6 as a dry material.

However, in the so-called coaxial microwave heat treatment equipment where microwaves are applied in the same direction as the axial direction of the rotating shaft, the strength of the microwave power or the heating temperature cannot be optimized depending on the position in the movement path of the water-containing material. There were problems in that it was difficult to control and the heating efficiency was poor.

The present invention has been made in view of the above-mentioned conventional circumstances, and is a continuous processing device for drying, etc., which can efficiently perform heat treatment using microwaves and can easily control the heating temperature. The purpose is to provide

In order to achieve the above object, the present invention disposes a vertical cylindrical body made of a dielectric material in a trap in a microwave oven, and equips the vertical cylindrical body with a screw blade, which is driven by a drive device. There are nine ways to set the axis of rotation to coincide with the axis of the vertical cylindrical body, so that the workpiece transferred by the screw blade inside the vertical cylindrical body is transmitted through the wall surface of the cylindrical body. It is designed to heat efficiently using microwave irradiation.

An embodiment of the present invention will be described below with reference to FIG.

The reference numeral 10 in FIG. 1 is a microwave oven. This microwave oven 10 has an upper and a lower cover 12 and a lower cover 13 made of scrap metal, respectively, at the upper and lower parts of a body plate 11 formed of a metal ring and having a cylindrical shape, respectively. It is closed and is provided with an upper lid 12 and a lower! 13 is a plurality of connecting rods 14 each having a threaded end formed therein;
are connected and fixed to each other by pushing the upper and lower ends into the through holes of the upper cover 12 and lower cover 13 and screwing nuts from the ends, and metal One end of the waveguide 15 is connected to the other end of the waveguide 15, and a microwave oscillation device 16 is provided at the other end of the waveguide 15.

Furthermore, inside the microwave oven 10, there is a body &11.
A vertical cylindrical body 17 having a small diameter and made of a dielectric material such as ceramic, glass, or Teflon has its axis aligned with the oven 1.
This vertical cylindrical body 17 is also closed at the top and bottom by the upper cover 12 and lower cover 13, respectively. Further, at a lower position Kl:l: of the side wall of this vertical cylindrical body 17, a gas supply pipe 18 for supplying an inert gas into the inside of this vertical cylindrical body 17 is connected, while a harmful A workpiece supply pipe 19 for supplying a workpiece such as a water-containing substance containing a substance into the vertical cylindrical body 17 and a gas discharge pipe 20 for discharging the gas inside the vertical cylinder 17 are provided, respectively. In addition, the lower lid 13 is provided with a processed material discharge pipe 21 for discharging the processed material inside the vertical cylindrical body 17 to the outside of the apparatus.
is connected. The to-be-processed material supply pipe 19 is provided with a hopper 22 at one end for receiving the to-be-processed material.
The other end of the screw feeder 23 is connected, and the gas discharge pipe 20 is connected to a condenser 24. In addition, the above-mentioned processing material supply pipe 19, processing material discharge pipe 21,
The gas supply pipe 18 and the gas discharge pipe 20 are both formed to a size that cuts off microwaves 1. On the other hand, in the center of the vertical cylinder 17, there is a pipe formed of metal or dielectric material. A rotary shaft 25 is arranged so as to coincide with the axis of the vertical cylindrical body 17. The rotating shaft 25 passes through the upper lid 12 and the lower lid 13 and is rotatably supported by the upper lid 12 and the lower lid 13 by bearings (not shown).
6 is connected n. The rotary shaft 25 also has a screw blade holder made of a dielectric material such as ceramic. This screw R27 has an inner edge 27
a is fixed to the outer circumferential surface of the rotating shaft 25, and its outer edge 27b is located close to the inner circumferential surface of the vertical cylindrical body 17.
It is inclined downward from the a side.

In the figure, 28 is a metal distribution plate that evenly distributes the microwaves sent from the waveguide 15 within the vertical cylindrical body 17, and 40 is a metal distribution plate that distributes the processed material through the processed material discharge pipe. 21 is a scraper leading to the opening, and 29 is a discharge valve.

Therefore, in the continuous processing apparatus z, when drying a material to be processed such as a water-containing material containing harmful substances, first, the drive device 26 is activated to rotate the rotating shaft 25 and the screw blade 27 is rotated. . In the next step r, an inert gas is supplied from the gas supply pipe 18 into the vertical cylindrical body 17, and the microwave oscillation device 16 is activated to oscillate microwaves.
The microwave is opened from the waveguide 15.
Lead into O. Then, the screw feeder 23 is operated to continuously feed the processed material stored in the hopper 22 from the processed material supply pipe 19 into the vertical cylindrical body 17. Open at the right time.

Then, the object to be processed falls onto the helical surface of the upper surface of the screw blade 27, and due to its inclination and gravity, is moved toward the inner peripheral surface of the vertical cylindrical body 17, and rotates while contacting the inner peripheral surface. and is gradually transported downward. microwave oven io
The microwaves that have entered the interior are transmitted through the wall of the vertical cylindrical body 17 made of dielectric material and are directly absorbed by the object to be treated.
As a result, the material to be treated is gradually dried and heated as it is transferred downward, and is continuously discharged from the material discharge 121 as a material having a predetermined moisture content. Further, the water vapor generated by drying and heating the object to be treated is guided along with the accompanying gas from the gas exhaust pipe 20 to the condenser 24, where it is cooled and condensed and separated.

Here, in the above-mentioned continuous processing apparatus, the screw Ji
! Since the object to be processed that has fallen onto the 27 is transferred downward without being stirred relatively, the dried object to be processed is less likely to be scattered as dust.

Furthermore, microwaves are transmitted through a vertical cylindrical body 1 made of dielectric material.
The screw blade 27 formed of a dielectric material enters the inside of the fi 11 wall from almost the entire surface of the wall through the side wall thereof, and the screw blade 27 formed of a dielectric material also penetrates therethrough. The object to be treated can receive microwaves from its entire circumference. Furthermore, since the screw blades 27 are vertical, the free surface area of the workpiece is much larger than in the case of conventional horizontal screw blades. Furthermore, microwaves gradually attenuate once they are absorbed by the object to be treated, and there is a limit to the depth of their penetration;
The thickness of the layer of the object placed on the upper surface of 27 becomes thinner in areas closer to the rotating shaft 25, where the microwaves are relatively weaker.
Microwaves penetrate to the center of the layer. 1. Therefore,
The efficiency of drying and heating the object to be processed is extremely high, and the heating temperature can be easily controlled.

Furthermore, in the continuous processing apparatus described above, by changing the rotational speed of the screw blades 27, the residence time of the object to be processed within the vertical cylindrical body 17 can be freely adjusted. , furthermore, the spiral surface of the upper surface of the screw R27 is
Since 7b is inclined so that it is below the inner edge 27&, even the objects to be processed, which would not fall without a large pinch with the screw blades that tend to incline, can be dropped at a small pitch, making the apparatus more compact. be able to. It is also easy to maintain the airtightness of the device. Incidentally, in the above description, the screw blades 27 are single and have equal pitches. However, the physical properties of the material to be treated vary depending on the material being handled, and also change as the moisture content decreases during the process of drying and heating. Therefore, in order to cope with this, screw blades 27 of various shapes are used. In Figures 1 and L2, the pitch PI on the lower side of the screw blades 27 is smaller than the pitch P2 on the upper side. This is the tit on the upper side of screw R27.
The material to be processed has a high water content and has poor flow, but the screw blade 2
7, the water content decreases and the flow rate becomes faster.
This is to prevent dust from being generated. Incidentally, the inclination θ of this screw 1R270 in the radial direction is preferably j' to 1700 with respect to the horizontal. For the same purpose, as shown in FIG.
The upper part 27c of 27 may be inclined, and the lower part 27d may be horizontal.

In the figure, a plurality of screw blades 27 are mounted on a rotating shaft 25 with a spacer 30 interposed between them. In this case, depending on the physical properties of the workpiece and changes in its physical properties during the drying and heating process, the workpiece can be combined with horizontal screw blades as described above, or the pitch and length can be appropriately selected. 27, the dust is transferred downward without being stirred relatively, or in the discontinuous portion where the spacer 30 is interposed, the dust is dropped and stirred to the extent that dust does not scatter, thereby increasing drying efficiency. Figure 5 shows the screw'! A plurality of vias 31 are provided on the outer edge 27bK of A27. Each piece 31 has a screw R2
7 has a plurality of long holes 31a extending in the radial direction, and a plurality of holes 32a screwed to the outer edge 27b of the screw blade 27 by penetrating the outer core 27b are passed through the long holes 31a. By screwing the Nand 32b onto the
It is locked to the screw blade 27 and can freely move in the radial direction of the screw blade 270. Therefore, the piece 31 comes into contact with the inner peripheral surface of the vertical cylindrical body 17 and rotates due to its own weight. Therefore, the workpiece is screw R
27 and the inner peripheral surface of the island-shaped cylindrical body 17, and a short bath of the processed material in the vertical cylindrical body 17 is prevented.Furthermore, by attaching this piece 31, Since the outer diameter of the entire screw blade 27 automatically becomes approximately equal to the inner diameter of the vertical cylindrical body 17, there is no need to precisely process the outer periphery of the screw R27, making it extremely easy to manufacture. 32a and Nando 32
b may be used to fix the piece 31 at an appropriate position and adjust the gap between the inner circumferential surface of the vertical cylinder 17 and the screw R27.

On the other hand, in the embodiment shown in FIG. 7, a distribution plate 28 is provided in the microwave oven 10 to ensure uniform propagation of microwaves. You may also provide nine wings. In addition, in the upper position of the screw fA27 where the moisture content of the workpiece is high, local heating of the workpiece may occur. This localized heating may be prevented by reducing it with a metal shield disposed at an appropriate distance from the outer surface of the sidewall.

Furthermore, W, as shown in the figure, microwave open I
A plurality of vertical cylindrical bodies 17 are arranged in parallel in O, a screw conveyor 33 is provided between the valley vertical cylindrical bodies 17, and each vertical cylindrical body 17 is provided with a screw lR27, and a drive device 26 A rotating shaft 25 may be provided to be rotated by a rotating shaft 25, thereby increasing the processing efficiency of the object to be processed.
Each vertical cylindrical body 17 is formed with a porous dielectric material, and the inside of the microwave oven 10 is made to have a negative pressure inside the vertical cylindrical body 17 using a pressure reducing device such as a blower or a vacuum pump. It is also possible to extract water vapor, decomposition gas, etc. generated by dry heating from the side wall of the vertical cylindrical body 17.

Further, FIG. 7 shows a plurality of microwave ovens 10 stacked one on top of the other, the above-mentioned vertical cylindrical body 17 being disposed therein, and a boundary portion IQa between each microwave oven 10. A metal member 35 is provided on the lower surface of the portion 27e of the screws 1 & 27 at positions corresponding to Device 1
6 is provided with a temperature controller 36. Each temperature controller 36 can control the Δ power of each microwave generated by each microwave oscillation device 16, and can optimally control the heating temperature in each microwave oven 10. ing. therefore,
The physical properties of Kamidokoro Tsubomono change as the moisture content decreases during the drying and heating process, but the heating temperature in each microwave oven 10 can be optimally adjusted according to this change, minimizing power loss. It can be held to a limit. In addition, here, the boundary part 10a between each microwave oven 10
is made of metal. i, fc1 boundary part 10
Part 27e of the screw blade 27 located at the position corresponding to a
Rotating shaft 25t: i is preferably made of metal, but it is not particularly necessary to make it metal as long as the shaft diameter is large enough to cut off microwaves.

Furthermore, a metal member 35 may be provided on the upper surface of the portion 27e of the screw blade 27 at a position corresponding to the boundary portion 10a. It is preferable that the pinch in this portion is a cutoff for microwaves, but it is not necessarily necessary to do so because even if some microwaves leak, there is no problem Ifi.

In FIG. r, the rotating shaft 25 is made of metal, and the boundary portion 10a
A short metal screw R27f is provided at a running position corresponding to the rotary shaft 25, separately from a dielectric screw blade 27g provided over substantially the entire length of the rotating shaft 25. Here, 37 in the figure is a stopper member.

Furthermore, the above device can be used as a combustion device for sludge distillation, incineration, catalyst regeneration, etc. by making them of heat-resistant steel or the like and selecting an appropriate gas body to be supplied to the gas supply pipe 18. Furthermore, it can also be used as a moving bed catalytic reaction device by using a catalyst instead of the object to be treated and allowing a reaction fluid to flow through the vertical cylindrical body 17. in this case,
It is a thermal theory that it is necessary to select an appropriate dielectric material depending on the processing temperature.

As explained above, in the continuous processing apparatus for drying, etc. of the present invention, the material to be processed, such as a water-containing material containing harmful substances, is heated by microwaves while being moved up the screw gK. The processed material is less likely to become dust and scatter. Furthermore, since the microwaves enter the inside of the vertical cylinder made of dielectric material by passing through the sidewalls from almost the entire surface of the sidewalls, the object to be processed can receive the microwaves from the entire circumference. Moreover, since the screw blades Fi are disposed with their axes directed upward and downward, the free surface area of the workpiece is large and its layer thickness is thin. Therefore, the heating efficiency of the object to be processed is extremely good, and the heating temperature can be easily controlled. Furthermore, it is possible to easily adjust the residence time of the device, make it smaller, maintain airtightness, etc.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing one embodiment of the present invention, Figs. 2 to 15 show other configurations of the screw blade, and Fig. 2 is a cross-sectional view when the lower pinch is made smaller than the upper one. , Fig. 3 is a sectional view when an inclined wing and a horizontal wing are combined, Fig. µ is a sectional view when they are combined via a plurality of screw spacers, and Fig. 5 (a) Figure 15 ('
b) Vi same side view. 6 to 9 are sectional views showing other embodiments, and FIG. 2 is a sectional view showing a conventional device. 10...Microwave open, 16...
・Microwave oscillator, 17... Police-shaped cylindrical body,
25. Curved/rotating shaft, 26... Drive device, 27.
...Screw wing, 30...Spacer,
31... Peace, 34... Song decompression device. Figure 2 Figure 3 Figure 4 Figure 5 (0) (bl

Claims (1)

[Claims]
A vertical cylindrical body is arranged, and the vertical cylindrical body with five and
1. A continuous processing device for drying, etc., characterized in that a rotating shaft is provided with screw blades and is rotated by a drive device so that its shaft load coincides with the axis of a vertical cylindrical body. (2) A vertical cylindrical body is disposed in nine consecutive microwave ovens, and the portion of the screw blade located at a position corresponding to the boundary between the microwave ovens is made of metal. 2. The continuous processing apparatus for drying, etc. according to claim 1, characterized in that a metal member is provided at said portion.