JPH0334634Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to a continuous processing device for drying, etc., which has a built-in screw and can freely adjust the residence time.

[Conventional technology]

Conventionally, various continuous dryers have been developed and commercially available. Among these, those that use mechanical stirring or air current stirring cannot avoid scattering of fine powder particles, making it difficult to maintain airtightness, while thin film types have drawbacks such as the inability to adjust residence time. have. By the way, continuous drying equipment that dries water-containing materials containing harmful substances such as radioactive materials has good airtightness and is designed to prevent harmful dust from scattering into the atmosphere along with the exhaust gas. No dust generation is required. In addition, substances containing harmful substances having various physical properties are often dried using the same apparatus, and it is desired that the residence time can be freely adjusted depending on the physical properties of the material to be dried.

[Problem that the invention attempts to solve]

To partially solve these problems, a hearth made of a metal spiral (horizontal screw) is installed in a vertical cylindrical furnace body, and the hearth is made of a metal spiral (horizontal screw) that is perpendicular to the vertical axis of the furnace body. There is a device that dries the material to be dried while lowering it sequentially over the hearth by controlling the residence time. This device has the advantage of being airtight and causing little dust to scatter. However, in the case of a device that targets drying materials that are not slippery, such as wet materials such as sludge, the pitch of the spiral body must be increased to prevent the material from adhering to the hearth and not moving. It won't be, but
When this device is used to process slippery materials, it immediately slides and the residence time cannot be controlled. On the other hand, when the pitch of the spiral body is made smaller, the problem is that the non-slippery substances described above cannot be moved, and the residence time cannot be adjusted according to the physical properties of the object to be treated using the same device as described above. It was hot. For this reason, none of the conventional continuous drying devices mentioned above can simultaneously satisfy all of the conditions required for continuous drying devices for water-containing materials containing harmful substances, and none of them can be used as continuous drying devices for the above purpose. It was inappropriate. In view of the above circumstances, it is an object of the present invention to provide a continuous processing apparatus for drying, etc. with a built-in screw, in which the residence time can be freely adjusted.

[Means to solve the problem]

Therefore, the continuous processing device for drying, etc. of the present invention has a vertical cylindrical device body, a rotating shaft provided along the cylindrical axis of the device body, an inner edge attached to the rotating shaft, and an outer edge attached to the rotating shaft. a screw that is close to or in contact with the inner circumferential surface of the cylindrical device main body; a drive mechanism that rotates the rotating shaft in a direction opposite to the twisting direction of the screw from the upper end to the lower end; and the cylindrical device a heating means provided on the outer circumferential surface of the main body, and an imaginary line where the screw intersects with a plane including the axis of the rotating shaft is inclined downward as it goes from the inner edge to the outer edge (i.e., The helical surface of the screw in the radial direction is inclined downward with respect to the rotation axis. In the following description, the screw described above will be referred to as an inclined screw.

[Effect]

The object to be dried, such as the material to be dried, placed on the helical surface of the inclined screw is transported to the inner circumferential surface of the cylindrical wall (hereinafter simply referred to as the inner circumferential surface) of the apparatus main body due to the radial inclined shape and rotation of the helical surface of the inclined screw. ) and rotates on the spiral surface of the inclined screw while contacting the inner peripheral surface. That is, since the helical surface of the screw is inclined in the radial direction, objects on the screw surface are located at the outer circumference of the screw (inner circumferential surface of the cylindrical wall of the main body of the device).
The area of contact with the inner peripheral surface of the cylindrical wall is extremely large compared to the conventional horizontal screw, and when the screw rotates, the object on the screw surface is subjected to frictional force with the inner peripheral wall. This acts to stop the screw at the current position, and improves the screw's slippage (that is, the object's slippage), so it is possible to hold the screw at its pitch even if it is a wet object or other non-slippery object that would not fall with a horizontal screw unless it is made at a large pitch. You will be able to move it without making it bigger. Due to the frictional force with the inner circumferential surface generated by the rotation of the screw and the gravity of the object, the object gradually descends downward along the upper surface of the inclined screw while contacting the inner circumferential surface. During this descending process, the object receives heat from the inner circumferential surface and continuously moves downward. In this case, the descending speed of the object on the spiral surface changes proportionally to the rotational speed of the inclined screw. Therefore, the residence time of the object within the device main body can be freely adjusted by adjusting the rotation speed of the inclined screw, and since the spiral surface of the inclined screw is inclined in the radial direction, With Screw, even objects that cannot fall unless they are made in a large pitch can be dropped in a small pitch. In addition, since there is no need to increase the screw pitch (advance angle of the screw) if the material is slippery,
The retention time of objects that have never moved, whether they are slippery or slippery, can be easily and freely adjusted by changing the rotational speed of the screw. Furthermore, since the object rolls and slides down the spiral surface of the inclined screw, the free surface area is large and
Since the spiral surface is inclined in the radial direction, the contact area between the inner circumferential surface as a heat transfer surface and the object is increased, and heat is effectively transferred. In addition, the object's residence time is uneven due to the difference in the descending speed of the object depending on the radial position in the horizontal screw (this is because the advance angle of the spiral screw is large at the inner periphery and becomes smaller toward the outer periphery). Because the spiral surface of the screw is inclined in the radial direction, most of the objects are located on the outer periphery of the screw (inner periphery of the cylindrical wall of the main body of the device).
, so it will be less.

【Example】

The present invention will be explained below with reference to the drawings. FIG. 1 shows an embodiment in which the device of the present invention is used as a drying device, and reference numeral 1 in the figure indicates a cylindrical device main body. At the top of the device main body 1,
A sealing lid 2 is provided, and a cone-shaped portion 3 is provided below. A discharge valve 3a for discharging dry matter is provided at the lower end of this cone-shaped portion 3. Further, a rotating shaft 4 is provided at the center of the cylindrical portion of the device main body 1, passing through the sealing lid 2. The rotating shaft 4 is rotatably held by a lower bearing 4a provided in the device main body 1 and supporting the lower end of the rotating shaft 4, and an upper bearing 4b provided in the sealing lid 2. Further, a screw 5 is attached to the rotating shaft 4. The screw 5 has an inner edge 5a fixed to the outer periphery of the rotating shaft 4, and an outer edge 5b located close to the inner circumferential surface of the apparatus main body 1. Further, a virtual line intersecting a plane including the axis of the rotating shaft 4 and the helical surface of the screw 5, that is,
The spiral surface in the radial direction of the device main body 1 is inclined downward with respect to the rotating shaft 4 (inclined screw). In addition, on the upper side of the cylindrical part of the device main body 1,
A water vapor discharge pipe 6 is attached. A water vapor condenser 7 is provided at the tip of the discharge pipe 6. Further, the rotary shaft 4 is provided with a variable rotation drive mechanism 8 that rotates the rotary shaft 4 in a direction opposite to the twisting direction downward from the upper end of the inclined screw 5. Further, a supply port 9 for supplying the material to be dried into the apparatus main body 1 is provided at the upper part of the airtight lid 2.
is provided. One end of a screw feeder 10 is connected to the supply port 9, and a drying material hopper 11 is provided at the other end of the screw feeder 10. Further, a jacket 12 is provided around the outer periphery of the main body 1 of the apparatus. This jacket 12
The heat medium fluid (hot water, Kaneklor [trade name], Dowsome [trade name], etc.) heated in the heat medium tank 12a is circulated by the heat medium circulation pump 12b. Next, a method of operating the dryer configured as described above will be explained. The operation is performed according to the following steps. 1) First, drive the rotating shaft 4 to rotate the inclined screw 5. 2) Circulating heat medium fluid through the jacket 12 to heat the inside of the device body 1. 3) Drive the screw feeder 10 to feed the material to be dried stored in the hopper 11 from the supply port 9 to the upper end surface of the inclined screw 5. Through the above operations, the material to be dried is continuously dried. Due to the radial inclination shape and rotation of the helical surface of the inclined screw 5, the material to be dried that has been placed on the helical surface of the inclined screw 5 due to the above operation approaches the inner circumferential surface of the apparatus main body 1, and It rotates on the spiral surface of the inclined screw 5 while contacting the surface. Due to the frictional force with the inner circumferential surface generated by this rotation and the gravity of the material to be dried, while in contact with the inner circumferential surface,
It gradually descends downward along the upper surface of the inclined screw 5. In this descending process, the material to be dried receives heat from the inner circumferential surface heated by the heat transfer fluid and the inclined screw 5 acting as a heat exchange piece, and moisture evaporates, and the material to be dried evaporates. dry. When the rotational speed of the inclined screw 5 is slow, drying is performed in the above-mentioned state. As the rotational speed increases, the material to be dried is pressed against the inner circumferential surface, a portion of which adheres, and is scraped off by the outer edge 5b of the rotating inclined screw 5. Normally, the rotational speed of the inclined screw 5 is as slow as several revolutions per hour. In this case, the rate of descent of the material to be dried changes proportionally to the rotational speed of the inclined screw 5. Therefore, the residence time of the material to be dried in the main body 1 of the apparatus can be freely adjusted by adjusting the rotational speed of the inclined screw 5, and the helical surface of the inclined screw is inclined in the radial direction. Therefore, even if a horizontal screw requires a large pitch to fall, it can be dropped in a small pitch, allowing the device to be made more compact. Further, since the device main body 1 has a simple structure, airtightness can be easily maintained. Furthermore, since the material to be dried rolls and slides down the spiral surface of the inclined screw 5, the free surface area is large. Furthermore, since the spiral surface is inclined in the radial direction, the contact area between the inner circumferential surface as a heat transfer surface and the material to be dried is increased, and the heat transfer surface can be used effectively. Furthermore, since no stirring is performed and heat is received through indirect heating, there is little chance of fine powder particles being scattered. Note that the generated water vapor is led to a water vapor condenser 7 through a discharge pipe 6, cooled, and condensed and separated. Further, the dried material is taken out to the outside by a discharge valve 3a. The above-mentioned heating means circulates a heat medium fluid such as steam or hot water through the jacket 12 provided on the outer peripheral surface of the device main body 1, but instead of this heating means, an electric heater, for example, is installed on the outer peripheral surface. Heating may be performed by providing a heating means such as resistance heating, low frequency induction heating, high frequency induction heating, and far infrared heating. In addition to heating by the heating medium fluid circulating in the jacket 12, the rotary shaft 4 and the inclined screw 5 are made hollow to provide appropriate heating medium paths to flow the heating medium fluid to promote moisture evaporation from the material to be dried. You can also do that. Furthermore, hot air may be blown from the bottom of the device main body to dry it. At this time, sufficient drying can be achieved by heating only with hot air, but if used in combination with the indirect heating method described above, the water vapor partial pressure will be reduced and water evaporation will be promoted, the drying effect will be enhanced with a small air volume, and it will be advantageous to generate less dust. It is. It is also effective to maintain the inside of the apparatus main body 1 in a reduced pressure state via the condenser 7, as this speeds up the drying process. Also, in the above description, a single inclined screw has been described. However, the physical properties vary depending on the material to be dried, and the physical properties also change as the water content decreases during the drying process. The inclined screw 5 has various shapes to accommodate these requirements. In FIG. 2, the lower pitch 13 of the inclined screw 5 is made smaller. In this case, the inclined screw 5 on which the material to be dried containing water and having poor flow is placed.
The pitch 13 may be made larger in the upper part, but if the moisture decreases and becomes easier to flow, the rate of descent will become faster.
In order to prevent this, the pitch 13 is made smaller as it goes downward. For the same purpose, as shown in FIG. 3, the upper part of the screw 14 is an inclined screw 5, and the imaginary line where the plane containing the axis of the rotating shaft 4 intersects the helical surface of the screw is continuously below the screw 5. It may be a horizontal screw 15 that is horizontal. FIG. 4 shows an inclined screw 5 in which a plurality of inclined screws 5 are discontinuously attached to the rotating shaft 4 with spacers 16 interposed between them, without providing a continuous inclined screw 5 over the entire length of the rotating shaft 4. This is an example. In this case, depending on the physical properties of the material to be dried and changes in physical properties during the drying process, it may be combined with the horizontal screw 15 or attached to the rotating shaft 4 by appropriately selecting the pitch and length. In this way, the material to be dried is separated from the inner circumferential surface and the screw 1 on the screw 14.
4 and the flow of the spiral surface of the screw 14 due to the gravity of the drying material, the drying material rolls downward, but further falls and is agitated at the discontinuous portion where the spacer 16 is interposed, improving drying efficiency. 5a and 5b, the outer edge 5b of the inclined screw 5 which comes into contact with the inner peripheral surface is formed by a piece 17 having a long hole 17a provided in the radial direction of the inclined screw 5. In FIGS. The piece 17 is secured to the outer edge of a small screw 18 whose radius is smaller than the radius of the main body 1 of the apparatus by means of a bolt or nut 18a through an elongated hole. Therefore, the piece 17 is
becomes free to move in the radial direction, the piece 17 descends due to gravity, its outer edge 5b contacts the inner circumferential surface and rotates, and the material to be dried falls from between the outer edge 5b and the inner circumferential surface. The main body 1 of the device for drying
By attaching this piece 17, the outer diameter of the inclined screw 5 is automatically adjusted to match the inside of the apparatus main body 1, so that the outer circumference of the inclined screw 5 can be precisely adjusted. There is no need for processing, making production extremely easy. Note that the piece 17 may be fixed in an appropriate position with bolts and nuts 18a, and the distance between the inner peripheral surface and the outer edge of the screw may be adjusted. Furthermore, by making the screw blades of the inclined screw 5 into perforated plates, the air flow path passes not only through the surface of the layer of the material to be dried placed on the spiral surface of the inclined screw 5, but also through the inside of the layer. It can also increase the drying effect. This perforated plate screw is particularly effective when used in combination with hot air. Note that the screw 5 is shown in FIGS. 4 and 5.
As shown in the figure, it can be attached to a cylindrical member 19, and by tightening this cylindrical member 19 to the rotating shaft 4, it can be made detachable. Furthermore, the above-mentioned equipment can be constructed from heat-resistant steel, etc.
It can be used as a combustion device for incineration, catalyst regeneration, etc. Furthermore, it can also be used as a moving bed catalytic reaction device by using a catalyst instead of the dried material and allowing the fluid to be reacted to flow through the device body 1. In this case,
If the reaction is exothermic, the jacket 12
The heat medium may be circulated until the reaction start temperature is reached, and then a cooling medium such as cold water may be circulated.

[Effect of the idea]

As described above, the apparatus of the present invention has the following characteristics because the object to be dried is moved downward by the rotation of the inclined screw. 1. Since the object rolls down on the surface of the screw, the free surface is large and the effective surface area of the object is large. 2 In the present invention, since the helical surface of the screw is inclined in the radial direction, objects on the screw surface are distributed thickly on the outer periphery of the screw (inner peripheral surface of the cylindrical wall of the device main body), and are In comparison, the contact area between the inner circumferential surface of the cylindrical wall and the object is extremely large, and when the screw rotates, the object on the screw surface is stopped at the current position by the frictional force with the inner circumferential wall, and the screw This improves the slippage of the screw (that is, the slippage of the object), so even objects with poor slippage, such as wet objects, which would not fall unless the pitch of the screw is made large with a horizontal screw, can be moved without increasing the pitch of the screw. In addition, objects with good sliding do not need to increase the screw pitch (advance angle of the screw), so they do not move as before, and the rotation speed of the screw can be changed for objects with poor slippage and objects with good slippage. Therefore, the residence time can be easily and freely adjusted, and it is possible to respond to a variety of object types and properties. 3. The uneven residence time of an object caused by the difference in the descending speed of the object depending on the radial position in a horizontal screw (for a spiral screw, the advance angle is large at the inner periphery and becomes smaller toward the outer periphery). In the present invention, since the spiral surface of the screw is inclined in the radial direction, most of the objects are located on the outer periphery of the screw (inner periphery of the cylindrical wall of the main body of the device), so that the number of objects can be reduced. . 4. Even on objects with poor slippage, it is possible to accelerate the descent of the helical screw without increasing the pitch as described above, and the device can be made more compact. 5 With horizontal screws, objects do not come into sufficient contact with the inner peripheral surface of the device, but in this invention, the spiral surface of the screw is inclined in the radial direction, so objects do not come into contact with the inner peripheral surface of the cylindrical wall of the device body. Since they are in good contact with each other, the inner peripheral surface can also be effectively used as a heat transfer surface. 6 In the present invention, since the helical surface of the screw is inclined in the radial direction, the screw surface area is larger than that of a horizontal screw of the same diameter, and can be effectively used as a heat transfer surface when necessary. 7. The external shape and structure are simple, it is easy to maintain airtightness, negative pressure operation is easy, and it is also possible to dispose of harmful or odorous substances without causing pollution. It has many advantages such as:

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing one embodiment of the device according to the present invention, and FIGS. 2 to 5 a and b are views of an inclined screw used in the device of the present invention.
The figure shows an inclined screw with a smaller pitch at the bottom, Figure 3 shows an inclined screw with an inclined screw and a horizontal screw installed in succession, and Figure 4 shows a short screw with a spacer in between. Figure 5a is a longitudinal cross-sectional view of an inclined screw whose outer edge is a movable piece, and Fig. 5b is a plan view of an inclined screw whose outer edge is a movable piece. It is. DESCRIPTION OF SYMBOLS 1... Device main body, 2... Sealing lid, 3... Cone-shaped part, 3a... Discharge valve, 4... Rotating shaft, 4a
...lower bearing, 4b...upper bearing, 5...inclined screw, 5a...inner edge, 5b...outer edge, 9...
...Supply port, 13...Screw pitch, 14...
Screw, 15...Horizontal screw, 16...
...Spacer, 17... Piece, 17a... Long hole,
18... Small screw, 18a... Bolt, nut, 19... Cylindrical member.

Claims (1)

[Scope of utility model registration request] A vertical cylindrical device main body, a rotating shaft provided along the cylindrical axis of the device main body, an inner edge attached to the rotating shaft, and an outer edge close to or in contact with the inner circumferential surface of the cylindrical device main body. Screw to do,
A driving mechanism for rotationally driving the rotating shaft in a direction opposite to the twisting direction of the screw from the upper end to the lower end, and a heating means provided on the outer peripheral surface of the cylindrical device main body, the screw and the rotating shaft A continuous processing device for drying, etc., characterized in that an imaginary line that intersects with a plane containing an axis line is inclined downwardly from the inner edge to the outer edge.