CN103217005A - Embedded counter flow type cylindrical wind cap used on fluidized bed dryer - Google Patents

Abstract

The invention discloses an embedded counter flow type cylindrical wind cap used on a fluidized bed dryer, relating to wind distribution technologies of a fluidized bed. The embedded counter flow type cylindrical wind cap comprises a protective sleeve, an outer sleeve and an inner embedded pipe, wherein the protective sleeve is fixedly connected with a wind distribution plate; the lower half part of the outer sleeve is fixedly connected with the protective sleeve; and the lower part of the inner embedded pipe is fixedly connected with the outer sleeve. The embedded counter flow type cylindrical wind cap has the advantages that when the wind cap is overhauled or cleaned, a worker can detach the outer sleeve and the inner embedded pipe from the position below the wind distribution plate to overhaul, clean and replace the wind cap, so that the technical difficulty in the dryer provided with a heat transfer coil pipe that the wind cap cannot be overhauled above the wind distribution plate is solved.

Description

A built-in counter-flow cylindrical air cap for fluidized bed dryer

field of invention

The invention relates to the technical field of air distribution for a fluidized bed, in particular to an embedded counterflow cylindrical air cap for a fluidized bed drier.

Background technique

Fluidized drying is a widely used method of particle drying. The fluidized bed dryer has the characteristics of simple structure, no moving parts, and long service life. The fluidized bed dryer is usually composed of an air chamber, an air distribution plate and a drying chamber. The air distribution plate has an air cap, and the fluidized gas enters the drying chamber through the air cap on the air distribution plate, so that the material is After being dried, the moisture precipitated from the drying of the material escapes with the fluidization gas; at the same time, a heat exchange coil is often installed in the dryer to provide a drying heat source.

The unimpeded and uniform air outlet of each air cap on the air distribution plate is the basic guarantee for the full fluidization of the material on the entire cross-section of the dryer, and the only way to effectively avoid local poor fluidization or dead zones in the dryer. The fundamental guarantee for the continuous and stable operation of the desiccator. However, because the material to be dried may be viscous when the humidity is high or during the drying process, for example, wet sludge with a moisture content of 76-80% will go through a viscous stage during the drying process, which will easily make the air cap of the fluidized bed dryer A blockage occurs. In addition, the fluidizing gas used in the fluidized bed dryer may be a dust-laden circulating gas. After the flying dust enters the air cap through the air distribution plate, it may also cause the air cap to be blocked. Therefore, it is necessary to regularly check and clean the hood.

Among the existing fluidized bed hoods, the slag-proof performance is better than the embedded counterflow cylindrical hood, such as the hood disclosed in Chinese patent 03200899.6, which includes an inline tube with two ends open and an outer tube with one end open; The upper part of the inner tube is nested in the outer tube, and a circular seam is defined between the two; there is a gap between the top of the inner tube and the outer tube; the inner tube and the outer tube are in sealing contact at the open end of the outer tube ; The side wall of the outer casing corresponding to the annular seam has a through hole for the fluidization gas to flow out; if the wind cap is blocked, remove the outer casing from above the air distribution plate for cleaning or replacement. However, in the fluidized bed dryer, there is a heat exchange coil above the air distribution plate, and the distance between the two is usually small, so it is impossible to check and clean the air cap from above the air distribution plate.

Contents of the invention

The purpose of the present invention is to propose a built-in counter-flow cylindrical air cap for fluidized bed dryers to overcome the defects of the prior art, and can complete inspection, cleaning and replacement under the air distribution plate, which is convenient for inspection and maintenance. At the same time, it has a good seal with the air distribution plate, thus solving the technical difficulty that the air cap cannot be inspected and repaired due to the heat exchange coil installed above the air distribution plate of the fluidized bed dryer.

To achieve the above object, the technical solution of the present invention is as follows:

A built-in counter-flow cylindrical air cap for fluidized bed dryers, including an outer casing and an embedded pipe; at least one through hole is provided on the side wall of the middle part of the outer casing with one end open and the other end closed; The outer diameter of the upper part of the embedded tube is smaller than the outer diameter of the middle and lower parts, and the junction forms a step. The inner tube is coaxially nested in the outer tube, and the outer circular surface of the middle and lower part of the inner tube is fixed to the inner wall of the outer tube; The upper surface of the step is not higher than the lowest point of the through hole on the side wall of the outer casing. There is a ring seam between the outer circular surface of the upper part of the embedded pipe and the inner wall of the outer casing, and there is a gap between the tops of the two, and the gap communicates with the ring seam; The seam communicates with the through hole on the side wall of the outer casing;

It also includes an annular sheath tube, the sheath tube is inserted into the central hole of the sheath tube, the outer circumference of the sheath tube is tightly connected to the inner wall of the sheath tube, and the through hole on the side wall of the sheath tube is located above the upper end surface of the sheath tube;

The outer peripheral wall of the sheath pipe is fixedly connected to the inner circle of the through hole on the air distribution plate.

The embedded counter-flow cylindrical hood used for the fluidized bed dryer has a boss on the circumference of the lower end of the inner tube, and the length from the upper ring surface of the boss to the upper end of the inner tube is less than the center of the outer tube. The depth of the blind hole.

The embedded counterflow cylindrical hood used for fluidized bed dryers, the outer circular surface of the middle and lower part of the embedded tube is fixedly connected with the inner wall surface of the outer casing by screws: the inner wall surface of the lower part of the outer casing is provided with an inner thread, the outer circular surface of the lower part of the embedded pipe is provided with external threads, the outer casing and the embedded pipe are screwed together, and are positioned through the upper ring surface of the boss of the embedded pipe.

In the embedded counterflow cylindrical air cap for fluidized bed dryer, there is a step on the outer circle below the through hole on the side wall of the outer casing, and the outer diameter of the lower part of the step of the outer casing is larger than the outer diameter of the upper part of the step.

In the embedded counter-flow cylindrical wind cap used in the fluidized bed dryer, there is an inward-facing boss on the upper inner wall surface of the sheath tube.

In the embedded counter-flow cylindrical hood used for the fluidized bed dryer, the outer circumference of the outer sleeve is tightly connected to the inner wall of the sheath tube, and is screw-fastened: there is a External thread, internal thread is provided on the inner wall below the boss of the sheath tube, the outer sleeve and the sheath tube are screwed together, and are positioned through the upper ring surface of the outer sleeve step and the lower ring surface of the boss of the sheath tube; the boss of the sheath tube The inner diameter of the enclosed central hole matches the outer diameter above the outer casing step.

In the embedded counter-flow cylindrical air cap for the fluidized bed dryer, the outer peripheral wall of the sheath pipe is fixedly connected to the inner circle of the through hole on the air distribution plate by welding.

The advantage of the present invention is that the disassembly of the air cap is completed from the bottom of the air distribution plate, that is, in the air chamber, which solves the problem that the air distribution plate cannot be inspected from above because the air distribution plate is close to the coil, and realizes the quick disassembly and replacement of the air cap. The board has good sealing performance, easy maintenance, convenient installation and replacement, time-saving and labor-saving, and greatly reduces the cost of installation and replacement.

Description of drawings

Fig. 1 is a schematic structural view of a built-in counter-flow cylindrical air cap for a fluidized bed dryer according to the present invention;

Fig. 2 is a schematic diagram of sheath pipe 1 of the present invention;

Fig. 3 is the schematic diagram of outer sleeve 2 of the present invention;

Fig. 4 is a schematic diagram of the embedded tube 3 of the present invention.

Detailed ways

An embedded counter-flow cylindrical air cap for fluidized bed dryers of the present invention adds a sheath tube to the existing embedded counter-current cylindrical air cap for fixing with the air distribution plate; The embedded tube fixed to the air distribution plate is fixed in the outer sleeve, and the outer sleeve is fixed in the sheath tube, and the embedded tube can be disassembled from the bottom of the outer sleeve, and the outer sleeve can be disassembled from the bottom of the sheath tube.

Welding is recommended for the connection between the sheath pipe and the air distribution plate; the connection between the outer casing and the sheath pipe and the connection between the outer casing and the embedded pipe can be done by spot welding or threaded connection.

The sheath tube is provided with an inwardly protruding annular boss for positioning the outer tube and the sheath tube, thereby ensuring that the through hole on the outer tube of the hood is at a certain height from the air distribution plate.

The lower part of the embedded tube is provided with a boss, which is used for the positioning of the outer tube and the inner tube, so as to ensure that the distance between the top of the embedded tube and the top of the outer tube is constant, so as to ensure that the resistance of the hood is not affected by the assembly.

An embodiment will be given below in conjunction with the accompanying drawings to describe the present invention in detail.

Example

As shown in FIG. 1 , the embedded reverse flow cylindrical hood includes a sheath tube 1 , an outer tube 2 and an inner tube 3 coaxially assembled from outside to inside.

Both ends of the sheath pipe 1 are open and fixed to the air distribution plate 5; the middle and lower part of the sheath pipe 1 is provided with an internal thread 11; the top of the internal thread 11 is a ring-shaped boss 12 protruding inward, which is used for screw connection. position.

The upper end of the outer sleeve 2 is closed and the lower end is open. The outer diameter of the upper half is slightly smaller than that of the lower half. One or several through holes 23 are arranged on the side wall of the upper half. When there are two or more than two through holes, the surrounding The side walls are evenly distributed; the lower half is provided with external threads 22; the outer casing 2 passes upwards from the sheath pipe 1, and the outer diameter of the upper half matches the inner diameter of the annular boss 12 of the sheath pipe 1, so The upper half can pass through the sheath tube 1 to expose the air distribution plate 5, and make the through hole 23 higher than the air distribution plate 5 at a certain height; the lower half of the outer sleeve 2 is provided with an external thread 22 connected to the inner wall of the sheath tube 1 , while also being provided with an internal thread connected with the outer wall of the embedded pipe 3 .

Both ends of the embedded tube 3 are open, extend into the outer casing 2 from the bottom, and are connected with the outer casing 2 through the external thread 33 at the lower part; a certain distance is kept between the top and the top inner wall of the outer casing 2, and the upper part is connected with the outer casing 2. There is a circular seam between the 2 inner walls. The fluidizing gas can enter from the bottom end of the embedded pipe, flow out from the top end, go down along the annular seam, and be ejected from the through hole 23 . The lower end of the external thread 33 of the embedded tube 3 is provided with a boss 32, which is used to limit the length of the embedded tube 3 extending into the outer casing 2, to ensure a constant distance between the tops of the two, and to ensure that the wind cap resistance is not affected by the screw assembly.

In order to facilitate the disassembly and assembly of the hood, the lower outer wall of the outer sleeve 1 and the inner tube 3 can be processed into a shape that is convenient for using a wrench. When it is necessary to overhaul, clean or replace the air cap, the outer casing can be unscrewed from the bottom of the air distribution plate, and then the inner tube can be removed from the outer casing.

Claims (7)

1. A built-in counter-flow cylindrical hood for a fluidized bed dryer, including an outer casing (2), an embedded pipe (3); the middle side wall of the outer casing (2) that is open at one end and closed at the other end At least one through hole (23) is provided on the top; the outer diameter of the upper part of the inner tube (3) opened at both ends is smaller than the outer diameter of the middle and lower part, and the joint part forms a step, and the inner tube (3) is coaxially nested in the outer tube (2) The outer circular surface of the inner and lower parts of the embedded pipe (3) is fixedly connected to the inner wall of the outer casing (2); the upper surface of the step on the outer circle of the inner embedded pipe (3) is not higher than the through hole (23) on the side wall of the outer casing At the lowest point, there is a circular seam between the upper outer surface of the embedded pipe (3) and the inner wall of the outer casing (2), and there is a gap between the tops of the two, and the gap communicates with the annular seam; the annular seam is connected to the outer casing (2) The through hole (23) on the side wall communicates; It is characterized in that, It also includes an annular sheath tube (1), the outer sleeve (2) is put through the central hole of the sheath tube (1), the outer circumference of the outer sleeve (2) is tightly fixed to the inner wall of the sheath tube (1), The through hole (23) on the side wall of the outer sleeve is located above the upper end surface of the sheath tube (1); The outer peripheral wall of the sheath pipe (1) is fixedly connected to the inner circle of the through hole on the air distribution plate (5). 2. The embedded counter-flow cylindrical air cap for fluidized bed dryer according to claim 1, characterized in that there is a boss (32) on the circumference of the lower end of the embedded pipe (3), and the convex The length from the upper ring surface of the platform (32) to the upper end of the embedded pipe (3) is less than the depth of the central blind hole of the outer casing (2). 3. The embedded counter-flow cylindrical air cap for fluidized bed dryer according to claim 2, characterized in that, the outer circular surface of the middle and lower part of the embedded pipe (3) is in contact with the inner surface of the outer casing (2). The wall surface is fixed, which is screw-fixed: the inner wall surface of the lower part of the outer casing (2) is provided with an internal thread (24), the outer circular surface of the lower part of the embedded pipe (3) is provided with an external thread (33), and the outer casing (2) and the embedded The pipe (3) is screw-connected and positioned through the upper ring surface of the embedded pipe boss (32). 4. The embedded counter-flow cylindrical air cap for fluidized bed dryer according to claim 1, characterized in that there is a step on the outer circle below the through hole (23) on the side wall of the outer casing, and the outer casing (2) The outer diameter of the lower part of the step is larger than the outer diameter of the upper part of the step. 5. The embedded counter-flow cylindrical air cap for fluidized bed dryer according to claim 1, characterized in that, there is an inward boss (12) on the upper inner wall surface of the sheath pipe (1) ). 6. The embedded counter-flow cylindrical hood for fluidized bed dryers according to claims 1, 4 and 5, characterized in that the outer circumference of the outer sleeve (2) is the same as that of the sheath tube (1) The inner wall is tightly connected, and it is screw-fixed: an external thread (22) is provided on the outer circular surface of the lower part of the step of the outer casing (2), and an internal thread (11) is provided on the inner wall below the sheath tube boss (12), and the outer casing ( 2) It is screw-fixed with the sheath tube (1), and positioned through the upper ring surface of the outer tube (2) step and the lower ring surface of the sheath tube boss (12); the center formed by the sheath tube boss (12) The inner diameter of the hole is adapted to the outer diameter above the step of the outer casing (2). 7. The embedded counter-flow cylindrical air cap for fluidized bed dryer according to claim 1, characterized in that, the outer peripheral wall of the sheath pipe (1) and the air distribution plate (5) The inner circle of the through hole is fixed, which is welding.

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