CN112374722A

CN112374722A - Sludge fluidized bed drier

Info

Publication number: CN112374722A
Application number: CN202011195513.4A
Authority: CN
Inventors: 张冬凌; 胡维杰; 卢骏营; 张长城
Original assignee: Shanghai Municipal Engineering Design Insitute Group Co Ltd
Current assignee: Shanghai Municipal Engineering Design Insitute Group Co Ltd
Priority date: 2020-10-30
Filing date: 2020-10-30
Publication date: 2021-02-19
Anticipated expiration: 2040-10-30
Also published as: WO2022089538A1; CA3170595A1; CN112374722B

Abstract

The invention provides a sludge fluidized bed dryer, which comprises a heat exchange coil (comprising a guide pipe and a branch pipe), a heat exchange coil jacket, an anti-abrasion clamping cover and the like; the guide pipes of the heat exchange coil pipe are vertically arranged, the branch pipes are horizontally arranged, and the heat exchange coil pipe jacket is arranged on two sides of the inner wall of the drying machine and fixes the anti-abrasion clamping cover on the guide pipes of the heat exchange coil pipe. The invention can effectively form physical protection at the junction of the guide pipe and the branch pipe of the heat exchange coil by a specific arrangement method of the heat exchange coil inside the drier and by protection measures such as a heat exchange coil jacket, an anti-abrasion clamping cover and the like, and destroy and inhibit the eddy current generated by the fluidized gas and material particles, thereby fundamentally lightening the abrasion of the heat exchange coil. The invention has the characteristics of simple processing method and convenient installation and maintenance.

Description

Sludge fluidized bed drier

Technical Field

The invention relates to sewage sludge drying treatment equipment, in particular to a sludge fluidized bed dryer.

Background

In the fluidized bed sludge dryer, circulating gas enters from a bottom air chamber of the fluidized bed sludge dryer under the action of a fan, so that internal wet sludge particles and materials generate a fluidization effect. The heat exchange coil is arranged in the dryer to provide heat energy for drying wet sludge, the wet sludge particles generate sufficient heat exchange with the heat exchange tube bundle in a fluidized state, and the wet sludge finally forms dry sludge particles. Wet sludge particles and bed materials in the drying machine fall back after reaching a certain bed pressure in the process of flowing upwards along with carrier gas, and when the particle concentration of the materials is not uniform in the fluidization process, abrasion is generated at the joint of the guide pipe and the branch pipe of the heat exchange coil, as shown in figure 1.

At present, in the prior art, the measures taken by the fluidized bed dryer in the wear-resistant aspect mainly include the adoption of a special gas distribution plate design to ensure uniform gas distribution in the dryer, and further reduce the wear of the dryer caused by too high local particle concentration, as shown in fig. 2. The abrasion-resistant measures are mostly suitable for fluidized bed drying equipment with small specification, and in the fluidized bed drying equipment with large and medium specification, the agglomeration phenomenon formed by particles is more complicated; another typical anti-wear measure is to use a high quality metal material for the heat exchange coil, which has a higher wear resistance than ordinary carbon steel. Such anti-wear measures increase the service life of the heat exchange coil to some extent, but have no significant anti-wear protection effect on the coil connections. In practice, the connection between the vertical and horizontal sections of the heat exchange coil (especially on the side facing the direction of the carrier gas wind) often presents problems of wear, leakage, etc.

The dry sludge particles form a fluidized state under the action of the carrier gas and move downwards according to the self gravity when reaching a certain bed pressure, and the formed dry particle vortex is the main cause of abrasion. In order to ensure a sufficient heat exchange area in the dryer, connection points are inevitably present in the design of the heat exchange coil. Aiming at the technical problems found in the prior art, a wear-resistant fluidized bed dryer needs to be provided.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a wear-resistant sludge fluidized bed dryer, which achieves the aim of reducing wear by the design of protecting the key parts of the connection points of a heat exchange coil.

In order to achieve the purpose of the invention, the technical scheme provided by the invention is as follows:

the invention provides a sludge fluidized bed dryer, which comprises a heat exchange coil, a heat exchange coil jacket and an anti-abrasion clamping cover, wherein the heat exchange coil jacket is arranged on the heat exchange coil; the heat exchange coil comprises a guide pipe and a branch pipe.

The heat medium in the technical scheme of the invention includes but is not limited to steam, heat conduction oil, hot water and other media.

The heat medium is distributed to the heat exchange coil pipe through the main distribution pipe, the guide pipes in the heat exchange coil pipe are vertically arranged, and the branch pipes are horizontally arranged, so that the connecting points of the guide pipes and the branch pipes are positioned on two sides of the inner wall of the drying machine, and the friction of fluidized gas and material particles on the drying machine is reduced. Heating medium enters the system through a heating medium pipeline inlet on the outer side of the outer wall of the fluidized bed drying machine and is distributed to the heat exchange coil pipes through a heating medium main distribution pipe; in the single-plate heat exchange coil, a heating medium firstly passes through the guide pipe and is redistributed to each branch pipe; after heat exchange, the heat medium flows out of the system through a guide pipe on the other side of the drier, a heat medium main distribution pipe and a heat medium pipeline outlet.

Furthermore, the heat exchange coil pipe jackets are arranged on two sides of the inner wall of the drying machine and are used for isolating the connecting points of the pipe branch pipes of the heat exchange coil pipe from material particles in the drying machine.

Furthermore, the anti-abrasion clamping cover is arranged on the guide pipe of the heat exchange coil pipe and is shaped like a horseshoe. The connecting points of the guide pipe and the branch pipe of the heat exchange coil pipe are protected by the clamping cover.

Furthermore, the size of the anti-abrasion clamping cover is designed according to the size of the conduit of the heat exchange coil pipe, so that the anti-abrasion clamping cover can be fixed on the conduit and can fully protect the connection point between the conduit and the branch pipe.

Preferably, the material of the heat exchange coil jacket can be provided with an anti-abrasion coating;

preferably, the material of the anti-abrasion card cover can be provided with an anti-abrasion coating;

preferably, the heat exchange tube side fins can be welded on the branch tubes of the heat exchange coil. The heat exchange pipe side fins are welded on the branch pipes of the heat exchange coil pipe and are arranged close to the heat exchange coil pipe jacket (towards the inner side of the drying machine), the two sides of each branch pipe are respectively provided with an upper group of side fins and a lower group of side fins, the number of the side fins is 4, and the tangential direction of the side fins is the same as the wind direction of the fluidizing gas. The heat exchange tube side fin has the following functions: the material particles are subjected to vortex cutting, so that the probability of abrasion of the material particles to the heat exchange coil is reduced. The side fin of the heat exchange tube is a rectangular steel sheet lacking a right angle.

The invention can effectively form physical protection at the junction of the guide pipe and the branch pipe of the heat exchange coil through the specific arrangement mode of the heat exchange coil inside the drier and the protection measures of the jacket and the anti-abrasion clamping cover of the heat exchange coil, and destroy and inhibit the eddy current generated by the fluidizing gas and the material particles, thereby fundamentally reducing the abrasion of the heat exchange coil. The invention has the characteristics of simple processing and convenient installation and maintenance.

Drawings

Fig. 1 is a schematic diagram of a heat exchanger of a conventional sludge fluidized bed dryer.

Fig. 2 is a gas distribution plate diagram of a conventional sludge fluidized bed dryer.

Fig. 3 is a diagram of the wear-resistant design (before the installation of the wear-resistant clamping cover) of the sludge fluidized bed dryer adopted by the invention.

Fig. 4 is a diagram of the wear-resistant design (after the anti-wear card cover is installed) of the sludge fluidized bed dryer adopted by the invention.

Fig. 5 is a schematic view of the exchange coil jacket (view a of fig. 4).

Fig. 6 is a schematic view of the wear protection card cover of the present invention (view from direction B of fig. 4).

Fig. 7 is a detailed view of a side fin of a heat exchange tube of the present invention (detail C of fig. 4).

In the figure:

1 outer wall of a fluidized bed dryer, 2 inlet and outlet of a heating medium pipeline, 3 main distribution pipes of the heating medium,

4 heat exchange coil pipes (4.1 ducts, 4.2 branch pipes),

5 heat exchange coil pipe jacket, 6 abrasionproof card cover, 7 heat exchange tube side fin.

Detailed Description

The following detailed description and specific examples of embodiments of the invention are given with reference to the accompanying drawings. The following examples are only for illustrating the technical solution of the present invention more clearly, but the scope of the present invention is not limited to the following examples.

Example 1

The embodiment is selected from sludge drying plants of certain sewage treatment plants. The sludge fluidized bed dryer is of a structure as shown in figures 3-7 and mainly comprises a heat exchange coil 4 (comprising a guide pipe 4.1 and branch pipes 4.2), a heat exchange coil jacket 5, an anti-abrasion clamp cover 6 and heat exchange pipe side fins 7.

In the embodiment, steam is adopted as a heating medium, enters the system through a heating medium pipeline inlet 2 on the outer side of the outer wall 1 of the fluidized bed dryer, and is distributed to the heat exchange coils 4 through a heating medium main distribution pipe 3. In a single-plate heat exchanger coil, the heating medium is first redistributed to each of the branch pipes 4.2 through the conduit 4.1. After heat exchange, the heat medium flows out of the system through a guide pipe 4.1 at the other side of the drier, a heat medium main distribution pipe 3 and a heat medium pipeline outlet 2.

In the heat exchange coil 4 of this embodiment, as shown in fig. 3, the conduit 4.1 is vertically arranged, and the branch conduit 4.2 is horizontally arranged, so that the connection point of the conduit 4.1 and the branch conduit 4.2 is located on two sides of the inner wall of the drying machine, thereby reducing friction generated by the fluidizing gas and the material particles.

The heat exchange coil jackets 5 are arranged at two sides of the inner wall of the drying machine, as shown in figure 3, and the connecting points of the guide pipe 4.1 and the branch pipe 4.2 in the heat exchange coil 4 are isolated from material particles in the drying machine. A positive profile view of the heat exchange coil jacket 5 is shown in fig. 5.

The anti-wear card cover 6 of the present embodiment is mounted on the conduit 4.1 of the heat exchange coil 4, and as shown in fig. 4, the shape thereof is horseshoe, and protects the connection point of the conduit 4.1 and the branch pipe 4.2 of the heat exchange coil 4. The wear-resistant cover 6 can be stably fixed on the guide pipe 4.1 and can fully protect the connection point between the guide pipe 4.1 and the branch pipe 4.2, as shown in fig. 6.

In the embodiment, the heat exchange coil pipe jacket 5 is provided with an anti-abrasion coating; the wear-resistant card cover 6 is provided with a wear-resistant coating.

And heat exchange pipe side fins 7 are welded on the branch pipes 4.2 of the heat exchange coil 4 and are arranged close to the heat exchange coil jacket 5 (towards the inner side of the drying machine), as shown in the attached figure 7. The two sides of each branch pipe are respectively provided with an upper group of side wing pieces 7 and a lower group of side wing pieces 7, and the number of the side wing pieces is 4. The tangential direction of the side flaps 7 should be the same as the direction of the fluidizing gas, so that the material particles can be cut into vortex, and the probability of abrasion of the heat exchange coil caused by the material particles is reduced. The side fin 7 of the heat exchange tube is a rectangular steel sheet without a right angle.

While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.

Claims

1. A sludge fluidized bed drier comprises a heat exchange coil (4), a heat exchange coil jacket (5) and an anti-abrasion clamping cover (6); the heat exchange coil comprises a guide pipe (4.1) and a branch pipe (4.2); heating medium enters a system through a heating medium pipeline inlet (2) on the outer side of the outer wall (1) of the fluidized bed dryer and is distributed to the heat exchange coil pipes (4) through a heating medium main distribution pipe (3); in the single-plate heat exchange coil, a heating medium firstly passes through the guide pipe (4.1) and is redistributed to each branch pipe (4.2); after heat exchange, the heat medium flows out of the system through a guide pipe (4.1) at the other side of the drier, a heat medium main distribution pipe (3) and a heat medium pipeline outlet (2).

2. The sludge fluidized bed dryer according to claim 1, characterized in that the conduit (4.1) is arranged vertically, the branch pipe (4.2) is arranged horizontally, and the connecting point of the conduit (4.1) and the branch pipe (4.2) is positioned at two sides of the inner wall of the dryer.

3. The sludge fluidized bed dryer according to claim 1, wherein the heat exchange coil jackets (5) are installed on two sides of the inner wall of the dryer, and the connecting points of the conduits (4.1) and the branch pipes (4.2) of the heat exchange coil are isolated from the material particles in the dryer.

4. The sludge fluidized bed dryer as claimed in claim 1, wherein the heat exchange coil jacket (5) is provided with an anti-wear coating.

5. The sludge fluidized bed dryer as claimed in claim 1, wherein the wear-resistant cover (6) is mounted on the conduit (4.1) of the heat exchange coil and is shaped like a horseshoe.

6. The sludge fluidized bed dryer as claimed in claim 1, wherein the size of the wear-resistant cover (6) is designed according to the size of the conduit (4.1) of the heat exchange coil, so as to ensure the fixing on the conduit (4.1) and protect the connection point between the conduit (4.1) and the branch pipe (4.2).

7. The sludge fluidized bed dryer as claimed in claim 1, wherein the wear-resistant card cover (6) is provided with a wear-resistant coating.

8. The sludge fluidized bed dryer as claimed in claim 1, wherein the side fins (7) of the heat exchange tube are welded on the branch tubes (4.2) of the heat exchange coil.

9. The sludge fluidized bed dryer according to claim 8, wherein the side fins (7) of the heat exchange tube are welded on the branch tubes (4.2) of the heat exchange coil and arranged close to the jacket (5) of the heat exchange coil, namely towards the inside of the dryer; the two sides of each branch pipe are respectively provided with an upper group of side wing panel and a lower group of side wing panel, the number of the side wing panels is 4, and the tangential direction of the side wing panels is the same as the wind direction of the fluidizing gas; the side fin (7) of the heat exchange tube is a rectangular steel sheet lacking a right angle.