JPS6127483A - Rotary drier using heat transfer plate through which heating medium pass - 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 (Industrial Field of Application) The present invention relates to a rotary dryer using a heat transfer plate through which a heating medium passes, and is used to dry powder in various fields such as chemical fertilizers, medicines, resins, foods, steel, and coal. Suitable for use in drying the body.

(Prior Art) Conventionally, as a dryer used for drying wet powder or granular material, there is one having a structure shown in FIG. 7, for example. In FIG. 7, reference numeral 1 denotes a rotary cylinder as the main body of the dryer, which is supported via tires 4.4 on support rollers 3, 3 provided on a base 2.2. In addition, around the zero-rotation cylinder 1, which is arranged with a slight downward slope in order to smoothly transfer the raw material from the raw material (product to be dried) charging port 5 at one end to the dried product outlet 6, A driven gear 7 is provided, a driving gear 8 meshes with the driven gear 7, and the rotational force of the prime mover 9 is transmitted via a reduction gear 10, so that the rotary cylinder 1 rotates around its axis. 11 is a paper outlet.

On the other hand, between both end plates of the rotary cylinder 1, a large number of heating tubes 12, 12, . Every book is supported. The heat medium to be flowed into these heating pipes 12 is transferred to a heat medium inlet pipe 14 attached to the rotary joint 13.
The heat medium is supplied through the heat medium inlet pipe 15. The heat medium exiting the heating pipe 12 is collected in a return header 16 and then discharged from a heat medium outlet pipe 18 through a return pipe 17. Although fins are attached around the heating tube 12, they are not shown.

This dryer generally has a length of 10 to 30 m, and in a rotating cylinder, wet powder or granular material is brought into contact with a heating tube heated by a heat medium, and as the rotating cylinder rotates, the wet powder or granules are sequentially moved to a discharge port. It is designed to dry continuously while drying.

(Problems to be Solved by the Invention) This type of dryer, which is usually called a steam tube dryer, has a large heating area per volume, has a large drying capacity, and has a high heat transfer rate. It is widely used because it does not require any processing equipment and has the advantage of being easy to operate. However,
This conventional dryer does not have the function of scraping up and stirring the raw material 1 when it comes into contact with the loaded raw material, and therefore cannot effectively utilize the heat transfer surface of the dryer. Ta. i.e. in contact with raw materials.

The contribution to heating and drying is limited to a part of the heating tube located at the bottom of the rotary cylinder, and the entire heat transfer surface has not been utilized effectively. Furthermore, stirring of the raw materials was not always sufficient, making it difficult to obtain a uniform drying effect.

(Means for Solving the Problems) In order to solve the above problems, according to the present invention, a large number of heat transfer bodies are disposed in the rotating cylinder in parallel with its axis, and one end of the rotating cylinder In a dryer in which a drying material supply section is provided at one end and a drying material discharge section is provided at the other end, a heat transfer plate through which the heating medium passes is used as the heat transfer body, and this is arranged in a radial or eccentric radial direction. A rotary dryer is provided, characterized in that:

The heat transfer plate used in the present invention preferably has a structure in which a passage is provided between two thermally conductive panels for passing a heating medium, such as steam, and the panel is heated by drawing the steam. . As a specific form of this heat exchanger plate, the third
Examples include a heat transfer plate 321 of a type called a dimple plate as shown in the figure, or a heat transfer panel 322 as shown in FIG. In the former case, the two thermally conductive panels 321a, 321a are fixed by the dimple portion 321b, and the panel 321a is attached to the portion other than the dimple portion.

A space 321c is formed between the space 321a and serves as a passage for the heating medium. In the latter case, two thermally conductive panels 322
A, 322a is formed in advance with a bulging portion having, for example, a semicircular cross section, and two panels are joined 222b so that each bulging portion faces each other, thereby creating a heating medium passage 322C in the ridge portion 322a. It is designed to cause the formation of

Further, as will be described in detail later with reference to embodiments of the present invention, such heat transfer plates include a plurality of heat transfer plates extending along the axis of the rotary cylinder and arranged in a radial pattern around the axis. It is attached to the end plate of the rotating cylinder so that it is located at The heat exchanger plates may be disposed radially around the axis of the rotary cylinder 21 as shown in FIG. 2, or eccentrically radially as shown in FIG. The heat transfer plate may have a flat plate shape as a whole as shown in FIG. 2, or may have a curved shape as a whole as shown in FIG.

(Function) As mentioned above, in the indirect heating rotary dryer, the heating body is composed of a heat transfer plate, and this heat transfer plate is arranged radially or eccentrically within the rotating cylinder. As it rotates, the raw material is scooped up by the heat transfer plate and rotates together with the heat transfer plate. In this way, each heat exchanger plate can effectively contact the raw material and can contribute to the drying of the raw material. Further, as the rotary cylinder rotates further, the raw material carried up by the heat exchanger plate falls and is mixed with the raw material below, so that stirring is performed more efficiently and uniform drying is achieved.

(Examples) Next, the present invention will be explained in more detail based on Examples.

FIG. 1 is an explanatory sectional view showing one embodiment of the present invention.

The indirect heating rotary dryer shown in Figure 1 has the same basic structure as the conventional rotary dryer with indirect heating tubes shown in Figure 7, except that a heat exchanger plate is used instead of a heating tube as the heating element. are essentially the same. That is, in FIG. 1, 21 is a rotary cylinder as the main body of the dryer, and a support roller 2 provided on a base 22
3.23 via tires 24.24.

In addition, this rotary cylinder 21 has a zero-rotation cylinder 21 installed with a slight downward slope in order to smoothly transfer the raw material from the raw material (product to be dried) loading port 25 at one end to the dried product outlet 26.
A driven gear (not shown) is provided around the , a driving gear (not shown) meshes with this, and the rotational force of the prime mover (not shown) is transmitted via a reduction gear (not shown). The rotary cylinder 21 is configured to rotate around its axis. 31
is the paper exit.

On the other hand, between both end plates of the rotary cylinder 21, a large number of heat transfer plates 32, 32 are supported radially around the axis in parallel with the axis. As described above, the arrangement of the heat exchanger plate 32 may be arranged in the manner shown in FIGS. 5 and 6 in addition to the manner shown in FIG. 2. In the case of FIG. 5, the stirring effect can be further enhanced, and in the case of FIG. 6, the scraping effect is more remarkable.

Steam is extracted into the heat exchanger plate 32 at the rotary joint 3.
3. Two contacts each via Mako Hold 34 v35
This is done by The drain obtained after the heat exchange is accumulated in the manifold 34 by natural fall using the slope of the dryer, and is discharged from the drain outlet 36 by the siphon effect.

The raw material is supplied into the dryer by the raw material inlet screw 37, scraped up by the heat transfer plate 32, and heated indirectly while being stirred. The vapor generated from the raw material is forcibly drawn out from the upper outlet 31 of the product hood 38. On the other hand, the dried product is discharged from the outlet 26 at the bottom of the outlet hood.

(Effects of the Invention) As described above, according to the present invention, the dryer is given the function of scraping up and stirring the raw materials, so that the drying efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is an explanatory sectional view showing one embodiment of the present invention, FIG. 2 is a cross-sectional view of the dryer shown in FIG. 1, and FIGS. FIGS. 5 and 6 are perspective views showing an example; FIGS. 5 and 6 are explanatory cross-sectional views showing the arrangement of the heat transfer plate of the present invention; FIG. 7 is a view showing an example of a conventional indirect heating rotary dryer. . 21... Rotating tube 25... Raw material inlet 26... Product outlet 32... Φ heat transfer plate

Claims (1)

[Claims] (1) Drying in which a large number of heat transfer bodies are arranged in a rotating cylinder parallel to its axis, and a dried material supply section is provided at one end of the rotating cylinder, and a dried material discharge section is provided at the other end. A rotary dryer characterized in that the heat transfer body is a heat transfer plate through which a heating medium passes, and the heat transfer plate is arranged radially or eccentrically.