A preheater lower outlet cyclone for dry process cement production line

Abstract

A preheater lower-outlet cyclone separator for dry-process cement production lines includes a lower-swirling inlet volute located at the upper end of the straight section shell of the cyclone separator. The air outlet at the lower end of the lower-swirling inlet volute is connected to the straight section shell of the cyclone separator. A discharge cylinder is located at the bottom of the straight section shell of the cyclone separator, and the straight section shell of the cyclone separator is connected to the discharge cylinder. A guide cylinder is located inside the straight section shell of the cyclone separator, with its lower end lower than the air outlet of the lower-swirling inlet volute. A guide cavity is formed between the guide cylinder and the straight section shell of the cyclone separator. A lower outlet duct is located on one side of the lower end of the straight section shell of the cyclone separator, and the lower outlet duct is connected to the straight section shell of the cyclone separator via a truncated cone. An anti-backflow cone is provided inside the discharge cylinder. Compared with traditional upper-outlet cyclone separators of the same output, this invention can reduce the frame height by about 4 meters, reduce the hot air duct by about 20 meters, and reduce the total weight and investment of the project.

Description

Technical Field

[0001] This utility model relates to the field of cement production equipment, and in particular to a preheater lower air outlet cyclone for dry process cement production lines. Background Technology

[0002] In the new dry process cement production, the preheater system plays a crucial role in preheating raw materials, separating gas and solids, and partially decomposing carbonates and evaporating moisture from raw materials. It is one of the core pieces of equipment in the new dry process cement production line system. Currently, most new dry process production lines built in China use a five-stage preheater. The cyclone separator in the preheater uses a traditional outlet air configuration, which generally results in high outlet resistance. Typically, the outlet pressure of the preheater system is above -5800 Pa, and the outlet exhaust gas temperature is above 320℃. If a cyclone separator is added and the existing uppermost cyclone separator is modified to build a six-stage preheater, the exhaust gas temperature can be reduced by more than 40℃. Based on a unit clinker heat consumption of 2980 kJ / kg·cl and an exhaust gas volume of 1.53 Nm³ / kg·cl, the unit clinker heat consumption can be reduced by 2.49%.

[0003] However, the traditional method of adding a preheater cyclone to the outlet cyclone requires raising the kiln tail frame by more than 12 meters, resulting in a large amount of work and high costs, which some older frame structures cannot withstand. Simultaneously, the preheater outlet pressure increases by more than -1000Pa, significantly increasing power consumption, making it difficult for factories to accept. The bottom-outlet cyclone, with its outlet duct located at the bottom, eliminates the reversal of airflow direction in the exhaust duct, resulting in a low-resistance, co-current flow structure. This effectively reduces preheater resistance and also lowers the number of bends, reducing the height of the kiln tail frame and the weight of the cyclone itself. Therefore, it is increasingly being used in preheater retrofits. However, the separation efficiency of existing bottom-outlet cyclones is generally low, ranging from 85% to 91%, failing to meet the requirement of ≥95% separation efficiency for the top-level cyclone in new dry-process cement preheaters. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a preheater bottom-outlet cyclone for dry process cement production lines. By adopting a bottom-outlet form, compared with the traditional top-outlet cyclone for the same output, the frame height can be reduced by about 4 meters, the hot air duct can be reduced by about 20 meters, and the total weight and investment of the project can be reduced.

[0005] To achieve the above objectives, this utility model adopts the following technical solution: a preheater lower air outlet cyclone for a dry process cement production line, comprising a lower swirling air inlet volute, a straight section shell of the cyclone, a guide tube, a lower air outlet pipe, a cone, a discharge cylinder, and an anti-backflow cone;

[0006] The downward spiral air inlet volute is located at the upper end of the straight section shell of the cyclone. The air outlet at the lower end of the downward spiral air inlet volute is connected to the straight section shell of the cyclone. A discharge cylinder is located at the bottom end of the straight section shell of the cyclone, and the straight section shell of the cyclone is connected to the discharge cylinder.

[0007] The guide tube is installed inside the straight section shell of the cyclone separator. The upper end of the guide tube protrudes from the straight section shell of the cyclone separator, and the lower end of the guide tube is lower than the air outlet of the lower swirling air inlet volute. A guide cavity is formed between the guide tube and the straight section shell of the cyclone separator.

[0008] A lower air outlet duct is provided on one side of the lower end of the straight section shell of the cyclone, and the lower air outlet duct is connected to the straight section shell of the cyclone through a cone; the discharge cylinder is provided with an anti-backflow cone.

[0009] Furthermore, the angle between the downward-swirling air inlet volute and the mounting horizontal plane is 15°.

[0010] Furthermore, the diameter d1 of the guide tube and the diameter D of the straight section shell of the cyclone tube satisfy the following condition: d1 / D = 0.3-0.4.

[0011] Furthermore, when the cyclone is used in the uppermost stage of the preheater, the diameter d2 of the lower outlet duct and the diameter D of the straight section shell of the cyclone satisfy: d2 / D=0.45-0.5; when used in other stages of the preheater, d2 / D=0.5-0.55.

[0012] Furthermore, the distance L1 between the bottom end of the guide tube and the air inlet of the lower air outlet duct satisfies the following condition with respect to the diameter D of the straight section shell of the cyclone tube: L1 / D = 0.65-0.7.

[0013] Working principle: The dust-laden airflow is forced to swirl downwards through the downward-swirling inlet volute and enters the straight section of the cyclone separator. The gas-solid separation is achieved by relying on the centrifugal force generated by the swirling flow. The separated dust enters the cone section of the cyclone separator and is discharged through the discharge cylinder, while the separated clean airflow is discharged from the lower outlet pipe.

[0014] The beneficial effects of this utility model are: This utility model adopts a bottom air outlet form, which can reduce the frame height by about 4 meters and the hot air duct by about 20 meters compared with the traditional top air outlet cyclone for the same output, thereby reducing the total weight and investment of the project.

[0015] The use of a downward-swirling inlet volute further optimizes the airflow trajectory, enabling the airflow to form a downward rotating trajectory in a shorter time. This reduces the collision interference between the airflow and the internal vortex, further reducing resistance and improving separation efficiency.

[0016] A cone is installed at the bottom air outlet duct to improve air velocity and separation efficiency. After passing through the cone, the airflow enters the enlarged bottom air outlet duct to reduce resistance.

[0017] An anti-backflow cone is installed in the cyclone cone to avoid the decrease in separation efficiency caused by secondary dust.

[0018] By rationally setting the diameter of the guide tube, the diameter of the air outlet pipe, and the distance between the guide tube and the air outlet pipe, the separation efficiency of the lower air outlet cyclone is further guaranteed to be ≥95%; the parts not described in detail in this utility model are existing commonly used technologies. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings:

[0020] Figure 1 This is a schematic diagram of the overall assembly structure;

[0021] Figure 2 This is a schematic diagram of the cross-sectional structure;

[0022] In the diagram: 1. Downward-swirling air inlet volute, 2. Straight section of cyclone casing, 3. Guide tube, 4. Downward-exit air duct, 5. Cone, 6. Discharge cylinder, 7. Anti-backflow cone. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0024] A preheater lower exhaust cyclone for a dry process cement production line includes a lower swirling air inlet volute 1, a straight section shell of the cyclone 2, a guide tube 3, a lower exhaust duct 4, a cone 5, a discharge tube 6, and an anti-backflow cone 7.

[0025] The downward spiral air inlet volute 1 is located at the upper end of the straight section shell 2 of the cyclone. The air outlet at the lower end of the downward spiral air inlet volute 1 is connected to the straight section shell 2 of the cyclone. The bottom end of the straight section shell 2 of the cyclone is provided with a discharge cylinder 6, which is connected to the discharge cylinder 6.

[0026] The guide tube 3 is installed inside the straight section housing 2 of the cyclone tube. The upper end of the guide tube 3 protrudes from the straight section housing 2 of the cyclone tube, and the lower end of the guide tube 3 is lower than the air outlet of the lower swirling air inlet volute 1. A guide cavity is formed between the guide tube 3 and the straight section housing 2 of the cyclone tube.

[0027] A lower air outlet duct 4 is provided on one side of the lower end of the straight section shell 2 of the cyclone tube. The lower air outlet duct 4 is connected to the straight section shell 2 of the cyclone tube through a cone 5.

[0028] The discharge cylinder 6 is equipped with an anti-backflow cone 7 inside.

[0029] The angle between the downward-swirling air inlet volute 1 and the horizontal mounting plane is 15°.

[0030] The diameter d1 of the guide tube 3 and the diameter D of the straight section shell 2 of the cyclone tube satisfy the following condition: d1 / D=0.3-0.4.

[0031] When the cyclone is used in the uppermost stage of the preheater, the diameter d2 of the lower outlet duct 4 and the diameter D of the straight section shell 2 of the cyclone satisfy: d2 / D=0.45-0.5; when used in other stages of the preheater, d2 / D=0.5-0.55.

[0032] The distance L1 between the bottom end of the guide tube 3 and the air inlet of the lower air outlet duct 4 satisfies the following condition with respect to the diameter D of the straight section shell 2 of the cyclone tube: L1 / D=0.65-0.7.

[0033] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A preheater lower outlet cyclone separator for a dry process cement production line, characterized in that, It includes a downward swirling air inlet volute (1), a straight section of the cyclone casing (2), a guide tube (3), a lower air outlet duct (4), a cone (5), a discharge cylinder (6), and an anti-backflow cone (7); The downward spiral inlet volute (1) is located at the upper end of the cyclone straight section shell (2). The air outlet at the lower end of the downward spiral inlet volute (1) is connected to the cyclone straight section shell (2). The bottom end of the cyclone straight section shell (2) is provided with a discharge cylinder (6), and the cyclone straight section shell (2) is connected to the discharge cylinder (6). The guide tube (3) is installed inside the straight section shell (2) of the cyclone tube. The upper end of the guide tube (3) is exposed outside the straight section shell (2) of the cyclone tube, and the lower end of the guide tube (3) is lower than the air outlet of the lower swirling air inlet volute (1). A guide cavity is formed between the guide tube (3) and the straight section shell (2) of the cyclone tube. A lower air outlet pipe (4) is provided on one side of the lower end of the straight section shell (2) of the cyclone tube. The lower air outlet pipe (4) is connected to the straight section shell (2) of the cyclone tube through a cone (5). The discharge cylinder (6) is equipped with an anti-backflow cone (7).

2. The preheater lower outlet cyclone according to claim 1, characterized in that, The angle between the downward-swirling air intake volute (1) and the horizontal mounting plane is 15°.

3. The preheater lower outlet cyclone according to claim 1, characterized in that, The diameter d1 of the guide tube (3) and the diameter D of the straight section shell (2) of the cyclone tube satisfy: d1 / D=0.3-0.

4.

4. The preheater lower outlet cyclone according to claim 1, characterized in that, When the cyclone is used in the uppermost stage of the preheater, the diameter d2 of the lower air outlet pipe (4) and the diameter D of the straight section shell (2) of the cyclone satisfy: d2 / D=0.45-0.5; when used in other stages of the preheater, d2 / D=0.5-0.

55.

5. The preheater lower outlet cyclone according to claim 1, characterized in that, The distance L1 between the bottom end of the guide tube (3) and the air inlet of the lower air outlet pipe (4) satisfies the following condition: L1 / D = 0.65-0.7.

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