JP2008014580A - Drying system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve drying efficiency by spreading an object to be dried like a thin film in a drying system using a vertical type drying apparatus for waste or the like. <P>SOLUTION: In the drying system for objects to be dried, the object F to be dried is put in an interior of a cylindrical drying tank 4, the drying tank is turned by a rotary shaft 6 arranged in the drying tank, and the objects to be dried is brought into contact with a heat transfer face 2 of a drying tank inner face by base blades 5 plurally arranged within a circumferential range of 360° as seen from above and having inclined faces rising in an opposite direction of a turning direction to carry out drying. At least one part of an adjacent base blade in the turning direction is arranged such that when the object to be dried flies out from a rear end of the base blade, it also reaches a base blade positioned higher as a whole, of base blades adjacently positioned to the rear in the turning direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a drying method for efficiently drying wastes and the like.

As a conventional drying method of this type, the drying tank is a vertical type, a jacket is provided so as to surround the drying tank, and high-temperature steam or a heating element is provided inside the drying tank to press the object to be dried against the heat transfer surface. There is a drying method using a vertical drying apparatus for drying by the above method.
In a drying method using a conventional vertical drying apparatus, heat is transferred to an object to be dried by centrifugal force generated by rotating a plurality of base blades installed in a cylindrical or frustoconical drying tank opened upward. Press against the surface to dry.
Japanese Patent No. 3057544

However, in the conventional drying method, when the object to be dried is pressed against the heat transfer surface by centrifugal force, the vertical cross section of the object to be dried is as shown in FIG. It is thick and thin on the upper side, forming an elongated triangular shape.
With such a cross-sectional shape, the thickness increases toward the lower side, so that the drying efficiency is worse toward the lower side.
Further, in the conventional drying method, with respect to the relationship between a certain base blade and an adjacent base blade located behind the rotation direction of the base blade, the tip position is lower than the rear end of the certain base blade. (I.e., it is not located generally above), the adjacent base blade is configured to receive the material to be dried that has jumped out from the rear end of the certain base blade. The object to be dried is not received by the adjacent base blade located.
Therefore, the present invention aims to solve the above-described problems and further improve the drying efficiency in this type of drying method.

In the present invention, an object to be dried is put into a cylindrical drying tank, and is rotated by a rotating shaft disposed in the drying tank. In the drying method of the object to be dried, the object to be dried is brought into contact with the heat transfer surface of the inner surface of the drying tank by a base blade having an inclined surface that rises in the direction opposite to the rotation direction.
When the material to be dried jumps out from the rear end of the base blade, it is adjacent to the rotation direction so as to reach the base blade located at the upper side among the adjacent base blades positioned rearward in the rotation direction. The problem has been solved by a method for drying an object to be dried, wherein at least a part of the matching base blades is disposed.

  If the base blade located at the bottom is connected to the rotating shaft by a scraping plate, and the object to be dried on the bottom surface of the drying tank is moved to the heat transfer surface side of the drying tank by the scraping plate, the drying efficiency is further increased. .

  In addition, if a baffle is provided at the top of the drying tank and the object to be dried is forced to drop by colliding with the baffle, the cycle of rising, falling and re-raising of the object to be dried is repeated. This improves the drying efficiency.

According to the present invention, since the longitudinal section of the object to be dried contacting the heat transfer surface can form a thin film with a more uniform thickness over the entire heat transfer surface, the drying efficiency can be improved. it can.
In addition, energy consumption can be saved as the drying efficiency is improved.

Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to these embodiments.
FIG. 1 is a longitudinal sectional view of a vertical drying apparatus (hereinafter referred to as “drying apparatus”) to which the present invention is applied. FIG. 2 is a plan view of a set of base blades at the bottom of the drying apparatus of FIG. 3 is a front view of a pair of lowermost base blades of the drying apparatus of FIG. 1, and FIG. 4 is a plan view of the lowermost base blade.
5 is a sectional view taken along line 5-5 in FIG. 4, and FIG. 6 is a sectional view taken along line 6-6 in FIG.

First embodiment

As shown in FIG. 1, the drying apparatus 10 to which the present invention is applied has a cylindrical shape (may be a truncated cone shape opened upward), and means for heating the heat transfer surface 2 on the inner surface of the drying tank 4 (FIG. (Not shown), a rotating shaft 6 that rotates in the R direction, and a plurality of base blades 5 that are provided in four stages on the rotating shaft 6 and that are within 360 degrees when viewed from above. Yes.
Each base blade 5 is inclined so as to rise in the direction opposite to the rotation direction R. In the first embodiment, three base blades 5 are provided on the same plane, and a total of four stages and twelve are provided.

2 is a plan view of a set of base blades 5 at the bottom, FIG. 3 is a front view thereof, and FIG. 4 is a plan view of the base blade 5 at the bottom.
As shown in FIG. 4, the bottom base blade 5 is provided with a scraping plate 8 connected to the rotating shaft 6, so that the object to be dried on the bottom surface of the drying tank is centrifuged as the base blade 5 rotates. It is made to move to the heat-transfer surface 2 side of the drying tank 4 by force.
5 and 6 are cross-sectional views taken along lines 5-5 and 6-6 in FIG. 4, respectively.
Further, depending on the properties of the object to be dried, a baffle B for forcibly dropping the object to be dried which has been lifted by the base blade 5 to the bottom of the drying tank 4 is shown in FIG. Provided.
The lowermost base blade 5 is approximately twice as long as the upper base blade.

FIG. 7 illustrates the movement of an object to be dried in the present embodiment in a development view (provided that the base blades 5 are aligned in a line when viewed in the vertical direction, and the bottom base blade is also The same as the length of the upper base blade.
The object to be dried squeezed by the lowermost base blade is raised along the inclination of the base blade. The object to be dried tends to jump out tangentially from the rear end of the base blade 5 due to inertia. However, since the frictional force, centrifugal force, and gravity act on the object to be dried in a complicated manner, The movement is directed upward, horizontally, and downward as indicated by arrows in the figure.
When viewed from above and below, the positions of the base blades do not have to be aligned as shown in FIG. 7, and may be staggered.

In the present invention, when an object to be dried is ejected from the rear end of the base blade by appropriately setting the length, angle, and position of the adjacent base blade positioned rearward in the rotation direction when viewed from a certain base blade. Of the adjacent base blades located rearward in the rotational direction, the base blades located above are also reached as a whole.
In addition, in the case of FIG. 7, “entirely located above” refers to a positional relationship such as the second base blade from the top of the right row with respect to the bottom base blade in the center row, for example. . In the conventional drying method, it is only considered that a material to be dried is received by the third and fourth base blades from the top of the right row with respect to the base blade at the bottom of the center row.

  In the present embodiment, the object to be dried is placed behind the base blade by making the interval between the steps smaller than before, appropriately setting the length, angle, and position of the base blade, or adjusting the rotation speed. When jumping out from the end, the dried material reached and received the base blades located generally above the adjacent base blades located rearward in the rotation direction.

Second embodiment

In the second embodiment, the heights of the base blades 5 are all different.
FIG. 8 is a development view illustrating the movement of the object to be dried in the present embodiment. As shown in the figure, the object to be dried scooped up by the lowermost base blade, when jumping out from the rear end of the base blade in the same manner as in FIG. Of the base blades, the base blades that are located generally above are also reached.

As described above, according to the drying method of the present invention, the drying efficiency can be improved as compared with the prior art by bringing the material to be dried close to a thin film with a uniform thickness over the entire heat transfer surface.
Needless to say, the number of stages and the number, length, and inclination angle of the base blades in each stage are not limited to those shown in the figure.
The positions of the base blades do not need to be aligned in the vertical direction or in the horizontal plane.

The longitudinal cross-sectional view of the vertical drying apparatus to which this invention is applied. FIG. 2 is a plan view of a set of base blades at the bottom of the drying apparatus of FIG. 1. FIG. 2 is a front view of a set of base blades at the bottom of the drying apparatus of FIG. 1. FIG. 2 is a plan view of the bottom base blade of the drying device of FIG. 1. FIG. 5 is a sectional view taken along line 5-5 of FIG. FIG. 6 is a sectional view taken along line 6-6 in FIG. The expanded view showing the motion of the to-be-dried object of 1st Embodiment. The expanded view showing the motion of the to-be-dried object of 2nd Embodiment. The longitudinal cross-sectional view of the to-be-dried object at the time of using the conventional drying apparatus.

Explanation of symbols

2 Heat transfer surface 4 Drying tank 5 Base blade 6 Rotating shaft 8 Scraping plate 10 Vertical dryer P Centrifugal force B Baffle F

Claims (3)

A plurality of sheets are disposed within a circumferential range of 360 degrees when viewed from the plane, in which a material to be dried is put into a cylindrical drying tank and rotated by a rotation shaft disposed in the drying tank. In the drying method of the object to be dried, the object to be dried is brought into contact with the heat transfer surface of the inner surface of the drying tank by a base blade having an inclined surface rising in the direction opposite to the rotation direction. At least a part of the base blades adjacent to each other in the rotational direction so as to reach the base blades located above all of the adjacent base blades located rearward in the rotational direction when jumping out from the rear end of the blades It is characterized by having arranged,
Drying method for objects to be dried.   The base blade located at the bottom is connected to the rotating shaft by a scraping plate, and the object to be dried on the bottom surface of the drying tank is moved to the heat transfer surface side of the drying tank by the scraping plate. 1 Drying method of an object to be dried.   The drying method according to claim 1, wherein a baffle is provided at an upper portion of the drying tank, and the object to be dried is forced to drop by colliding with the baffle.

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