Anti-accumulation of fine powder in a coarse powder separator inner cylinder

Abstract

The utility model discloses a kind of coarse powder separators inner cylinder of anti-powder accumulation, it is related to coarse powder separator technical field, including cylinder, sealed communication pipe, inlet pipe and outlet pipe, sealed communication pipe is connected with coarse powder separator middle part, and sealed communication pipe is close to coarse powder separator middle part one end and penetrates inverted conical gravity separation chamber, adjustable ball valve is provided on sealed communication pipe. The setting of sealed communication pipe constructs the communication passage of cylinder and external atmosphere, since inner cylinder forms closed space and keeps pressure balance with atmosphere by the communication pipe, therefore, there is no negative pressure state in sealed communication pipe, when cylinder appears wear hole due to long-term scouring of coal dust airflow, the space inside cylinder and coal dust negative pressure airflow area form conduction, the pressure difference formed by both can effectively prevent coal dust airflow from entering the inside of cylinder through wear hole, prevent spontaneous combustion risk caused by excessive powder accumulation, and then significantly reduce the possibility of explosion of coarse powder separator.

Description

Technical Field

[0001] This utility model relates to the field of coarse powder separator technology, and in particular to an inner cylinder of a coarse powder separator that prevents powder accumulation. Background Technology

[0002] The working principle of an axial coarse powder separator utilizes gravity separation, impact separation, and centrifugal separation. During operation, the coarse powder separator experiences significant direct erosion wear. The main wear areas are the lower cone section and the base of the inner cylinder's support points, where airflow directly impacts the inner cylinder, creating eddy current wear. Although these areas are treated with ceramic lining and other wear-resistant methods, long-term operation can still lead to localized wear and the formation of holes. Coal dust can enter the inner cylinder through these holes, accumulating. When the accumulation of dust is large and special operating conditions deteriorate, it can lead to spontaneous combustion, posing a significant hazard of explosion to the inner cylinder and the entire coarse powder separator.

[0003] In view of this, the present invention is proposed to solve the above-mentioned technical problems. Utility Model Content

[0004] The purpose of this utility model is to provide an inner cylinder for a coarse powder separator that prevents powder accumulation, so as to solve the technical problem in the prior art where the inner cylinder of the axial coarse powder separator is worn and forms holes due to long-term operation, and powder accumulates in the holes, which is prone to spontaneous combustion and has the risk of explosion.

[0005] The technical solution of this utility model is: an inner cylinder for a coarse powder separator that prevents powder accumulation, comprising:

[0006] The cylinder body, from bottom to top, includes a lower part of the coarse powder separator, a middle part of the coarse powder separator, and an upper part of the coarse powder separator that are connected to each other. The upper part of the coarse powder separator has a cylindrical centrifugal separation chamber inside, and the middle part of the coarse powder separator has an inverted conical gravity separation chamber inside, with the lower end of the inverted conical gravity separation chamber being a cone.

[0007] A sealed connecting pipe is connected to the middle of the coarse powder separator, and the end of the sealed connecting pipe near the middle of the coarse powder separator passes through the inverted conical gravity separation chamber. An adjustable ball valve is installed on the sealed connecting pipe.

[0008] The inlet pipe is located at the bottom of the coarse powder separator, and its upper end is connected to the inverted conical gravity separation chamber.

[0009] The outlet pipe is located on the upper part of the coarse powder separator and is connected to the cylindrical centrifugal separation chamber. The end of the outlet pipe away from the upper part of the coarse powder separator is connected to the inlet section of the powder discharge machine.

[0010] Furthermore, a deflector baffle is installed inside the cylindrical centrifugal separator.

[0011] Furthermore, multiple explosion-proof doors are installed on the upper part of the coarse powder separator.

[0012] Furthermore, a return powder pipe is connected to the middle of the coarse powder separator, and the end of the return powder pipe away from the middle of the coarse powder separator is connected to the feed inlet of the coal mill.

[0013] Furthermore, an anti-wear tile is fitted onto one end of the sealed connecting pipe near the middle of the coarse powder separator.

[0014] By adopting the above technical solution, this utility model has the following beneficial effects:

[0015] The sealed connecting pipe establishes a communication channel between the cylinder and the external atmosphere. Under normal operating conditions, because the inner cylinder forms a sealed space and maintains pressure balance with the atmosphere through this connecting pipe, there is no negative pressure within the sealed connecting pipe. When wear holes appear in the cylinder due to long-term scouring by pulverized coal airflow, the internal space of the cylinder becomes connected to the negative pressure airflow area of ​​the pulverized coal. At this time, under the action of system negative pressure, the external atmosphere will be quickly introduced into the cylinder through the sealed connecting pipe. Since the atmospheric pressure is higher than the negative pressure of the pulverized coal airflow, the pressure difference between the two can effectively prevent the pulverized coal airflow from entering the cylinder through the wear holes, avoiding the continuous accumulation of pulverized coal at the holes. This can eliminate the hidden danger of pulverized coal deposition in the wear area in real time, prevent the risk of spontaneous combustion caused by excessive pulverized coal accumulation, and thus significantly reduce the possibility of explosion of the coarse powder separator, providing a reliable passive protection mechanism for the safe and stable operation of the pulverizing system. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but do not constitute an undue limitation of the present invention. Obviously, the drawings described below are merely some embodiments; those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings:

[0017] Figure 1 This is a schematic diagram of the inner cylinder of the coarse powder separator for preventing powder accumulation provided in this embodiment of the application.

[0018] Reference numerals in the attached drawings: 1. Lower part of coarse powder separator; 2. Middle part of coarse powder separator; 3. Upper part of coarse powder separator; 4. Deflecting baffle; 5. Cone; 6. Inlet pipe; 7. Return powder pipe; 8. Explosion-proof door; 9. Outlet pipe; 10. Sealed connecting pipe; 11. Adjustable ball valve.

[0019] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the present invention in any way, but rather to illustrate the concept of the present invention to those skilled in the art by referring to specific embodiments. Detailed Implementation

[0020] The specific embodiments of this utility model will be described in further detail with reference to the accompanying drawings.

[0021] See Figure 1 As shown in the figure, this application provides an inner cylinder for a coarse powder separator that prevents powder accumulation, including: a cylinder body, a sealed connecting pipe 10, an inlet pipe 6, and an outlet pipe 9. The cylinder body, from bottom to top, includes a lower part 1, a middle part 2, and an upper part 3 of the coarse powder separator that are connected to each other. The upper part 3 of the coarse powder separator has a cylindrical centrifugal separation chamber inside, and the middle part 2 of the coarse powder separator has an inverted conical gravity separation chamber inside, with the lower end of the inverted conical gravity separation chamber being a cone 5. The sealed connecting pipe 10 is connected to the coarse powder separator. The middle section 2 is connected, and the sealed connecting pipe 10 passes through the inverted conical gravity separation chamber at one end near the middle section 2 of the coarse powder separator. An adjustable ball valve 11 is installed on the sealed connecting pipe 10. The upper end of the inlet pipe 6 is located at the bottom of the lower section 1 of the coarse powder separator, and the upper end of the inlet pipe 6 is connected to the inverted conical gravity separation chamber. The outlet pipe 9 is located on the upper section 3 of the coarse powder separator, and the outlet pipe 9 is connected to the cylindrical centrifugal separation chamber. The end of the outlet pipe 9 away from the upper section 3 of the coarse powder separator is connected to the inlet section of the powder discharge machine. A deflecting baffle 4 is installed inside the cylindrical centrifugal separation chamber.

[0022] It should be noted that the pulverized coal airflow enters the cone 5 in the middle part 2 of the coarse powder separator through the inlet pipe 6. Large coal particles are separated by gravity. The pulverized coal airflow then passes through the deflector baffle 4, resulting in impact separation. During the rotation of the pulverized coal airflow, centrifugal force separation occurs. The coarse powder returns to the coal mill, while the fine powder is discharged through the outlet pipe 9 into the pulverizer. The design flow velocity of the inlet pipe 6 and the outlet pipe 9 is 18-20 m / s, and the opening angle of the deflector baffle 4 is 30°-50°.

[0023] During operation of the coarse powder separator, the lower end of the sealed connecting pipe 10 can be manually probed for negative pressure to determine the wear condition of the cylinder. When a hole appears inside the cylinder and leaks, a negative pressure is formed at the outer opening of the sealed connecting pipe 10. The pressure can be adjusted by the adjustable ball valve 11 to ensure a slight negative pressure to prevent internal powder accumulation and reduce the amount of coal powder airflow entering the cylinder. Because the external airflow is small, the impact on the pulverizer is also small. During operation, the degree of wear inside the cylinder can be determined by the magnitude of the negative pressure in the sealed connecting pipe 10. If the negative pressure is too large, the wear inside the cylinder is severe. The system can be paused during low-load periods to repair the hole, which facilitates later maintenance.

[0024] In the above scheme, the sealed connecting pipe 10 connects the cylinder to the external atmosphere. During normal operation, since the inner cylinder is a closed space connected to the atmosphere, the sealed connecting pipe 10 has no negative pressure. When the cylinder is worn down by the pulverized coal airflow and produces holes, the internal space of the cylinder is connected to the negative pressure airflow of the pulverized coal. Under the action of negative pressure, the external atmospheric airflow enters the cylinder through the sealed connecting pipe 10, making the atmospheric pressure inside the cylinder greater than the negative pressure of the pulverized coal airflow. This prevents the pulverized coal airflow from entering the cylinder, avoids the pulverized coal from continuing to accumulate in the holes formed by wear, eliminates the deposition of pulverized coal, and thus prevents the risk of spontaneous combustion and explosion of the entire coarse powder separator due to excessive pulverized coal accumulation.

[0025] See some possible implementations. Figure 1 As shown, the upper part 3 of the coarse powder separator is equipped with multiple explosion-proof doors 8. The explosion-proof doors 8 are important safety protection devices in the pulverizing system. When an explosion occurs inside the system, the high-pressure gas generated by the explosion is released quickly to prevent the coarse powder separator from being damaged due to overpressure, thereby avoiding the accident from escalating.

[0026] See some possible implementations. Figure 1 As shown, the middle part 2 of the coarse powder separator is also connected to the return powder pipe 7. The end of the return powder pipe 7 away from the middle part 2 of the coarse powder separator is connected to the feed port of the coal mill. The coarse powder separation utilizes gravity separation, impact separation and centrifugal separation, so that large coal particles enter the coal mill through the return powder pipe 7 for further grinding.

[0027] Causes of explosions during coarse powder separator operation:

[0028] The coal powder airflow is separated in the cylinder of the coarse powder separator. Qualified coal powder enters the fine powder separator and powder silo, while unqualified coal powder enters the coal mill for further grinding through the return powder pipe 7. The entire circulation power source of the pulverizing system is the pulverizer. The coarse powder separator is located at the inlet section of the pulverizer, which is under negative pressure. The main cause of the explosion during the operation of the coarse powder separator is that the inner cylinder in the middle of the coarse powder separator is a closed space. When wear forms holes in the inner cylinder, coal powder will enter and accumulate inside the inner cylinder. The accumulated powder spontaneously combusts, leading to an explosion of the coarse powder separator.

[0029] In some possible implementations, an anti-wear tile is fitted on one end of the sealed connecting pipe 10 near the middle part 2 of the coarse powder separator. The anti-wear tile is used to protect the sealed connecting pipe 10 inside the middle part 2 of the coarse powder separator and prevent the coal powder airflow from causing wear to the sealed connecting pipe 10.

[0030] This specific embodiment is merely an explanation of the utility model and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of protection of this utility model.

Claims

1. An inner cylinder for a coarse powder separator that prevents powder accumulation, characterized in that, include: The cylinder comprises, from bottom to top, a lower part (1) of a coarse powder separator, a middle part (2) of a coarse powder separator, and an upper part (3) of a coarse powder separator. The upper part (3) of the coarse powder separator has a cylindrical centrifugal separation chamber inside, and the middle part (2) of the coarse powder separator has an inverted conical gravity separation chamber inside, with the lower end of the inverted conical gravity separation chamber being a cone (5). A sealed connecting pipe (10) is connected to the middle part (2) of the coarse powder separator, and the end of the sealed connecting pipe (10) near the middle part (2) of the coarse powder separator passes through the inverted conical gravity separation chamber. An adjustable ball valve (11) is provided on the sealed connecting pipe (10). The upper end of the inlet pipe (6) is located at the bottom of the lower part (1) of the coarse powder separator, and the upper end of the inlet pipe (6) is connected to the inverted conical gravity separation chamber. The outlet pipe (9) is located on the upper part (3) of the coarse powder separator and is connected to the cylindrical centrifugal separation chamber. The end of the outlet pipe (9) away from the upper part (3) of the coarse powder separator is connected to the inlet section of the powder discharge machine.

2. The inner cylinder of the coarse powder separator for preventing powder accumulation according to claim 1, characterized in that, The cylindrical centrifugal separator is equipped with a deflector baffle (4).

3. The inner cylinder of the coarse powder separator for preventing powder accumulation according to claim 1, characterized in that, The upper part (3) of the coarse powder separator is provided with multiple explosion-proof doors (8).

4. The inner cylinder of the coarse powder separator for preventing powder accumulation according to claim 1, characterized in that, The middle part (2) of the coarse powder separator is also connected to a return powder pipe (7), and the end of the return powder pipe (7) away from the middle part (2) of the coarse powder separator is connected to the feed port of the coal mill.

5. The inner cylinder of the coarse powder separator for preventing powder accumulation according to claim 4, characterized in that, The sealed connecting pipe (10) is fitted with a wear-resistant tile at one end near the middle (2) of the coarse powder separator.

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