A pneumatic conveying pump

Abstract

The utility model relates to the technical field of delivery pump, concretely is a kind of pneumatic delivery pump, including pump body and main gas pipe, the top feed inlet of pump body is equipped with pneumatic rotary feed valve, the top of pump body is equipped with exhaust valve, the sidewall of pump body is equipped with radio frequency admittance material level switch, for detecting the material level in pump body, the lower part of pump body is equipped with gasification chamber, the gasification chamber is communicated with pump body cavity, the main gas pipe is connected with external compressed gas source, and gas flow is respectively delivered to pump body and gasification chamber by multiple pipelines, and check valve and stop valve are connected in series on each pipeline, the right side of gasification chamber outlet is equipped with discharge valve, the pneumatic rotary feed valve uses rotary valve flap, and sealing surface uses wear-resistant ceramic material, the utility model aims at solving the problem that the opening and closing of the feed valve of the existing pneumatic delivery pump cannot be switched according to the material level and other working conditions of conveying process.

Description

Technical Field

[0001] This utility model relates to the field of delivery pump technology, specifically a pneumatic delivery pump. Background Technology

[0002] In the ash removal system of thermal power plants, pneumatic conveying pumps are the core equipment in the conveying of dry ash materials (fly ash). They use gas as the power medium and drive fly ash particles to achieve suspension or push-type transfer through the kinetic energy of the air. This non-contact conveying principle is just right for the characteristics of fly ash, which is dry, loose, easy to generate dust and not easy to stick. It reduces blockage and material accumulation in the conveying process from the root, making the material transfer smoother. It easily connects the dust collection equipment, ash silos and other key upstream and downstream nodes of the ash removal system, and becomes the central hub of material flow.

[0003] The existing pneumatic conveying pump feed valve cannot switch according to the material level and other working conditions during the conveying process, resulting in a disconnect between the feeding and conveying stages. This ultimately leads to a decrease in feeding efficiency and an increase in the risk of conveying interruption, making it difficult to meet the needs of continuous and stable operation of the ash removal system in thermal power plants. Utility Model Content

[0004] The purpose of this utility model is to provide a pneumatic conveying pump to solve the problem that the opening and closing of the feed valve of the existing pneumatic conveying pump cannot be switched according to the material level and other working conditions during the conveying process.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] A pneumatic conveying pump includes a pump body and a main air pipe. A pneumatic rotary feed valve is installed at the top inlet of the pump body, and an exhaust valve is installed at the top of the pump body. A radio frequency admittance level switch is installed on the side wall of the pump body for detecting the material level in the pump body. A gasification chamber is installed at the bottom of the pump body and is connected to the pump body cavity. The main air pipe is connected to an external compressed air source and delivers airflow to the pump body and the gasification chamber through multiple pipes. Each pipe is equipped with a check valve and a shut-off valve connected in series. A discharge valve is installed at the right outlet of the gasification chamber.

[0007] Preferably, the pneumatic rotary feed valve adopts a rotary valve disc, the sealing surface is made of wear-resistant ceramic material, and the exhaust valve is staggered from the pneumatic rotary feed valve.

[0008] Preferably, the porous fluidized bed plate inside the gasification chamber is made of stainless steel.

[0009] Preferably, a first diverter pipe is connected between the main air pipe and the upper part of the pump body, and the first diverter pipe is connected in series with a first check valve and a third shut-off valve.

[0010] Preferably, a second branch pipe and a third branch pipe are connected in parallel between the main gas pipe and the vaporization chamber. The second branch pipe and the third branch pipe supply gas to the left and front areas of the vaporization chamber, respectively. The second branch pipe is connected in series with a first shut-off valve and a second check valve, and the third branch pipe is connected in series with a second shut-off valve and a third check valve.

[0011] Preferably, a pressure detection component is installed on the first diversion pipe.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. By using the radio frequency admittance level switch for real-time detection, the dynamic adaptation and switching between the opening and closing of the pneumatic rotary feed valve and the material level conditions in the pump body are realized. This completely solves the problem of disconnection between the feeding and conveying stages of traditional pneumatic conveying pumps. It avoids problems such as material accumulation and increased conveying resistance caused by excessive feeding, and prevents waste of conveying efficiency caused by insufficient feeding. It significantly improves the adaptability and efficiency of the feeding process. At the same time, the orderly connection between the feeding and conveying stages effectively reduces the risks of pipeline blockage and system pressure fluctuations caused by improper feeding, reduces the possibility of conveying interruption, and thus ensures the continuous and stable operation of the ash removal system in thermal power plants, fully meeting the power plant's requirements for efficient and reliable operation of the dry ash conveying process. Attached Figure Description

[0014] Figure 1 This is a front view of the entire utility model;

[0015] Figure 2 This is a left view of the entire utility model;

[0016] Figure 3 This utility model Figure 1 Enlarged view of point A in the middle.

[0017] In the diagram: 1. Pump body; 2. Pneumatic rotary feed valve; 3. Exhaust valve; 4. First check valve; 5. First shut-off valve; 6. Second shut-off valve; 7. Second check valve; 8. Third check valve; 9. Gasification chamber; 10. Discharge valve; 11. T-connector; 12. Pressure transmitter; 13. Bend; 14. Pressure gauge; 15. RF admittance level switch; 16. First branch pipe; 17. Main gas pipe; 18. Second branch pipe; 19. Third branch pipe; 20. Third shut-off valve. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Please see Figures 1 to 3 This utility model provides a technical solution.

[0020] A pneumatic conveying pump includes: a pump body 1, which is a vertical tank-shaped structure, welded from Q355B wear-resistant steel plate, with the tank wall thickness adapted to the working pressure requirements, and the design working pressure ≤0.5MPa, providing a core cavity for material storage and conveying.

[0021] The pneumatic rotary feed valve 2 is located at the top feed port of the pump body 1 and is used to control the entry of materials. It adopts a rotary valve disc, which has a fast opening and closing speed. The sealing surface is made of wear-resistant ceramic material. It is linked with the PLC control system to realize precise switching control between the feeding and conveying stages and prevent air pressure leakage in the pump body 1 during the conveying process.

[0022] The exhaust valve 3 is located at the top of the pump body 1 (offset from the pneumatic rotary feed valve 2). It is opened during the feeding stage to balance the air pressure inside and outside the pump body 1, eliminate feeding resistance, and ensure that the material falls smoothly. It is closed during the conveying stage to ensure the sealing and pressure resistance inside the pump body 1.

[0023] The radio frequency admittance level switch 15 is installed on the side wall of the pump body 1 to detect the material level inside the pump body 1. It is installed at a preset material level height on the side wall of the pump body 1 and adopts radio frequency admittance detection technology. It is not affected by material humidity, dust and dielectric constant. It monitors the material level inside the pump body 1 in real time. When the material is full, it sends a switch signal to the PLC to trigger the pneumatic rotary feed valve 2 to close and stop feeding.

[0024] The gasification chamber 9 is located at the lower part of the pump body 1 and is connected to the cavity of the pump body 1. It has a built-in porous fluidized bed plate (pore diameter 0.5-1mm) made of Q235 stainless steel with a distribution uniformity of ≥95%. After the external compressed air source is introduced, the air diffuses through the fluidized bed plate to form a uniform airflow, so that the material at the bottom of the pump body 1 is fully fluidized, reducing the material conveying resistance.

[0025] The piping assembly includes a first branch pipe 16, a main air pipe 17, a second branch pipe 18, and a third branch pipe 19. The main air pipe 17 is the main air source channel, with one end connected to an external compressed air source. The first branch pipe 16 connects the main air pipe 17 to the upper part of the pump body 1 and is used to supplement the air pressure delivered in the pump body 1. The second branch pipe 18 and the third branch pipe 19 are connected in parallel to the main air pipe 17 and the vaporization chamber 9, respectively supplying air to the left and front areas of the vaporization chamber 9 to ensure fluidization uniformity. All pipes are made of 304 stainless steel, and the pipe diameter is matched according to the air source flow rate.

[0026] The valve assembly includes a first check valve 4, a first shut-off valve 5, a second shut-off valve 6, a second check valve 7, a third check valve 8, and a third shut-off valve 20. A first diverter pipe 16 is connected in series with the first check valve 4 and the third shut-off valve 20. The first check valve 4 prevents backflow of airflow in the pump body 1. The third shut-off valve 20 is used to control the opening and closing of the first diverter pipe 16. A second diverter pipe 18 is connected in series with the first shut-off valve 5 and the second check valve 7. The first shut-off valve 5 controls the opening and closing of the second diverter pipe 18. The second check valve 7 prevents backflow of airflow in the vaporization chamber 9. A third diverter pipe 19 is connected in series with the second shut-off valve 6 and the third check valve 8, and has the same function as the second diverter pipe 18, realizing a dual-branch redundancy design.

[0027] The pressure detection component is installed on the first branch pipe 16, not directly on the pump body 1, which simplifies the opening design of the side wall of the pump body 1. The first branch pipe 16 is the air supply channel for external air to flow to the pump body 1, and its internal pressure is directly related to the internal pressure of the pump body 1. Installed on the first branch pipe 16, the pressure status of the air supply branch can be directly monitored, avoiding detection errors caused by dust adhering to the material inside the pump body 1. At the same time, installation and maintenance are more convenient. It includes a pressure gauge 14, a bend 13, a three-way connector 11, and a pressure transmitter 12. The three ends of the three-way connector 11 are respectively connected to the first branch pipe 16, the bend 13, and the pressure transmitter 12. The other end of the bend 13 is connected to the pressure gauge 14. The pressure transmitter 12 converts the pressure signal into an electrical signal and transmits it to the PLC control system to realize linkage control (converting the pressure signal into a 4-20mA current signal and transmitting it to the PLC).

[0028] The discharge valve 10 is located at the discharge port on the right side of the gasification chamber 9. It is a pneumatic ball valve that is linked with the PLC control system. It automatically opens and closes according to the pressure and material level signal inside the pump body 1 to control the material discharge rhythm and ensure the stability of the conveying.

[0029] This solution specifically involves the application of this pneumatic conveying pump in the positive pressure ash removal system of a thermal power plant. The working process is divided into four stages:

[0030] Feeding stage (material storage and preparation): After receiving the ash accumulation signal from the dust collector ash hopper, the PLC controls the pneumatic rotary feed valve 2 to open and simultaneously opens the exhaust valve 3. The exhaust valve 3 balances the air pressure inside and outside the pump body 1, allowing the dry fly ash to fall smoothly into the pump body 1 from the top feed port under gravity. When the RF admittance level switch 15 detects that the material in the pump body 1 has reached the preset level (or the feeding time has reached the PLC set value, whichever is true), it immediately sends a full signal to the PLC. The PLC then controls the pneumatic rotary feed valve 2 and the exhaust valve 3 to close sequentially, and the feeding stage ends.

[0031] Fluidization and pressurization stage (material fluidization and system pressurization): Air source intervention: After the pneumatic rotary feed valve 2 and exhaust valve 3 are closed, the PLC starts the air source system, and the external compressed air source is connected to the main air pipe 17, while controlling the valves of each pipeline to open in linkage.

[0032] When the first check valve 4 and the third shut-off valve 20 are opened, the gas source enters the upper part of the pump body 1 through the first diverter pipe 16 to initially pressurize the inside of the pump body 1; when the first shut-off valve 5 and the second check valve 7 are opened, the gas source is injected into the vaporization chamber 9 through the second diverter pipe 18; when the second shut-off valve 6 and the third check valve 8 are opened, the auxiliary gas source is injected into the vaporization chamber 9 through the third diverter pipe 19.

[0033] The dual gas sources entering the gasification chamber 9 pass through the built-in porous fluidized bed plate and diffuse evenly, so that the fly ash in the lower part of the pump body 1 is fully fluidized (in a suspended state). At the same time, the upper part of the pump body 1 is continuously supplied with gas through the first diversion pipe 16, and the system pressure gradually rises.

[0034] Stage termination: When the pressure transmitter 12 detects that the pressure inside the pump body 1 has risen to the preset value (0.15MPa, which can be adjusted according to the ash conveying distance), it immediately sends a pressure signal to the PLC, the fluidization pressurization stage ends, and the pump body enters the conveying preparation state.

[0035] Conveying stage (directed conveying of fluidized materials): Conveying start-up: After the PLC receives the pressure compliance signal, it controls the discharge valve 10 on the right side of the gasification chamber 9 to open. The fluidized fly ash enters the ash conveying pipeline from the discharge port on the right side of the gasification chamber 9 under the action of system pressure (air pressure on the upper part of the pump body 1 plus airflow thrust of the gasification chamber 9).

[0036] Continuous conveying: During the conveying process, the main air pipe 17 continuously diverts the air source, the first diversion pipe 16 keeps replenishing the air, maintains a stable pressure in the pump body 1, and avoids the interruption of conveying due to a sudden drop in pressure. The second diversion pipe 18 and the third diversion pipe 19 continuously supply air to the gasification chamber 9 to ensure that the material is always in a fluidized state and to prevent pipe blockage. The pressure transmitter 12 feeds back the pressure data to the PLC in real time. The PLC dynamically adjusts the opening of the shut-off valves of each pipeline according to the pressure changes to optimize the air flow rate.

[0037] Phase termination: As material is continuously discharged, the pressure inside pump body 1 gradually decreases. When the RF admittance level switch 15 detects that the material inside pump body 1 is below the minimum material level (or the pressure drops to close to the pipeline resistance, about 0.08MPa), the PLC determines that the material conveying is complete and the conveying phase ends.

[0038] Purging stage (pipeline residue cleaning): Purging start: PLC controls the main air pipe 17 to continue supplying air, keeping all pipeline valves open, and the second branch pipe 18 and the third branch pipe 19 inject high-pressure airflow into the gasification chamber 9 to purge the inside of the gasification chamber 9 and the ash conveying pipeline at the outlet section of the discharge valve 10 to remove residual materials.

[0039] After completion, the PLC shuts down each component in a preset sequence. First, it closes the air supply valves of the first diversion pipe 16, the second diversion pipe 18, and the third diversion pipe 19, and then closes the discharge valve 10. The system returns to its initial state and waits for the next feeding signal to complete a complete work cycle.

[0040] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pneumatic conveying pump, comprising a pump body (1) and a main air pipe (17), characterized in that: A pneumatic rotary feed valve (2) is installed at the top feed port of the pump body (1). An exhaust valve (3) is installed at the top of the pump body (1). A radio frequency admittance level switch (15) is installed on the side wall of the pump body (1) to detect the material level in the pump body (1). A gasification chamber (9) is installed at the bottom of the pump body (1). The gasification chamber (9) is connected to the cavity of the pump body (1). The main air pipe (17) is connected to an external compressed air source and delivers airflow to the pump body (1) and the gasification chamber (9) through multiple pipes. Each pipe is connected in series with a check valve and a shut-off valve. A discharge valve (10) is installed at the right discharge port of the gasification chamber (9).

2. The pneumatic conveying pump according to claim 1, characterized in that, The pneumatic rotary feed valve (2) adopts a rotary valve disc and the sealing surface is made of wear-resistant ceramic material. The exhaust valve (3) is arranged separately from the pneumatic rotary feed valve (2).

3. The pneumatic conveying pump according to claim 1, characterized in that, The gasification chamber (9) has a built-in porous fluidized bed plate made of stainless steel.

4. The pneumatic conveying pump according to claim 1, characterized in that, A first diversion pipe (16) is connected between the main air pipe (17) and the upper part of the pump body (1). The first diversion pipe (16) is connected in series with a first check valve (4) and a third shut-off valve (20).

5. The pneumatic conveying pump according to claim 1, characterized in that, The main gas pipe (17) and the vaporization chamber (9) are connected in parallel by a second branch pipe (18) and a third branch pipe (19). The second branch pipe (18) and the third branch pipe (19) supply gas to the left and front areas of the vaporization chamber (9) respectively. The second branch pipe (18) is connected in series with a first shut-off valve (5) and a second check valve (7). The third branch pipe (19) is connected in series with a second shut-off valve (6) and a third check valve (8).

6. The pneumatic conveying pump according to claim 4, characterized in that, Pressure detection components are installed on the first shunt pipe (16).

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