System and method for realizing pneumatic powder conveying by utilizing air circulation

Abstract

The invention provides a system and a method for realizing pneumatic powder conveying by utilizing gas circulation, a gas supplementing inlet is communicated with a recovery dust remover and a recovery buffer tank, the recovery dust remover is communicated with the recovery buffer tank, and the recovery buffer tank is communicated with gas inlets of a plurality of compressors; a gas outlet of the compressor is communicated with a plurality of finished product bins connected in parallel through a gas buffer tank, the finished product bins are communicated with a target bin, and the target bin is communicated with a recovery dust remover through an emptying filter to form circulation. Under the condition that powder exists in a finished product bin or a target bin is not full, stable operation can be continuously carried out, nitrogen is recycled in the conveying process, the nitrogen utilization rate is increased, the emptying amount is reduced, and the waste gas treatment amount is reduced.

Description

Technical Field

[0001] The invention relates to the field of pneumatic conveying of powders, and in particular to a system for pneumatic conveying of powders by utilizing air circulation and a conveying method thereof. Background Art

[0002] In the past, the powder pneumatic conveying process used to use the sending tank to convey the powder intermittently: the industrial nitrogen in the device was decompressed to the pressure level required for conveying, and the powder was added to the sending tank after passing through the relevant valves. When the sending tank was conveying, the pneumatic feed valve and the balance valve were opened, and the pneumatic isolation valve was opened, and the material fell freely. When the system detected the signal of the level meter in the sending tank, the pneumatic feed valve and the balance valve were closed, and compressed nitrogen was introduced from the upper part of the tank to pressurize the tank. When the pressure reaches the set value, the fluidization valve group at the cone of the sending tank is opened to introduce a small amount of nitrogen to loosen the local powder and granular materials, so as to facilitate the discharge of the materials. When the pneumatic discharge valve is opened, the denser material flow enters the conveying pipeline continuously. After the material enters the conveying pipeline, the accompanying blowing valve group is opened, so that the continuous material flow is conveyed to the target bin under the pressure of the compressed nitrogen. After the nitrogen conveys the powder to the target bin, it is directly emptied through the vent filter or enters the tail gas washing system. Summary of the invention

[0003] The main purpose of the present invention is to provide a system and method for pneumatically conveying powders by utilizing air circulation, so as to solve the problem that in the conventional pneumatic conveying process of powders, a sending tank is used to intermittently convey the powders.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a pneumatic conveying system for powders is realized by utilizing gas circulation, the gas supplementary inlet is connected with the recovery dust collector and the recovery buffer tank, the recovery dust collector is connected with the recovery buffer tank, the recovery buffer tank is connected with multiple compressor air inlets, the compressor air outlet is connected with multiple parallel finished product bins through the gas buffer tank, the finished product bin is connected with the target bin, and the target bin is connected with the recovery dust collector through the vent filter to form a circulation.

[0005] In the preferred embodiment, the gas supplementary inlet is connected to the recovery buffer tank through a supplementary gas regulating valve, and a buffer tank switch valve is provided between the recovery dust collector and the recovery buffer tank.

[0006] In a preferred embodiment, a plurality of compressors are arranged in parallel, a compressor inlet switch valve is provided between the recovery buffer tank and the plurality of compressors, and the plurality of compressors are connected to the gas buffer tank via a buffer opening valve.

[0007] In the preferred embodiment, the recovery buffer tank is connected to the buffer opening valve through an overpressure venting regulating valve.

[0008] In the preferred embodiment, the gas buffer tank is connected to the air inlet at the top of one of the finished product bins through a branch main valve, and the discharge port at the bottom of the finished product bin is connected to the target bin through a powder feed switch valve.

[0009] In the preferred embodiment, three pipelines are connected in parallel between the branch main valve and the powder feed switch valve, and a pigging branch valve is provided on the first pipeline at the top of the three pipelines; A first pneumatic regulating valve is provided on the middle pipeline, and an inlet and outlet valve is provided between the first pneumatic regulating valve and the parallel pipeline of the pigging branch valve; A second pneumatic regulating valve is provided on the lowest pipeline; An outlet valve is provided between the three pipeline main pipes and the powder feed switch valve.

[0010] In the preferred embodiment, a discharge port at the lower end of the finished product bin is provided with a bin discharge switch valve.

[0011] In a preferred embodiment, the method comprises: S1. Close the buffer tank switch valve between the recovery dust collector and the recovery buffer tank, open the compressor inlet switch valve above the compressor, open the supplementary gas regulating valve on the recovery buffer tank, and add gas to the recovery buffer tank to 0.005-0.006MPa, and then adjust the supplementary gas regulating valve to the automatic gas supply mode; S2. Open the compressor outlet valve under the compressor, start the compressor and open the overpressure venting regulating valve at the same time to ensure stable operation of the compressor; S3. Adjust the pressure reducing valve from the compressor to the gas buffer tank to reduce the pressure to 0.2-0.5MPa, and open the buffer opening valve; S4. Determine that the powder in the finished product warehouse is transported to the target warehouse, close the main valve of the gas branch, and open the main valve of the branch that needs to transport the powder; S5. Open the branch main valve, pigging branch valve, inlet sender valve, outlet sender valve, and powder feed switch valve to replace the air in the pipeline; S6. After the replacement is completed, the pigging branch valve is closed, the buffer tank switch valve and the outlet switch valve are opened, and the powder initially enters the transmitter. By adjusting the output of the first pneumatic regulating valve and the second pneumatic regulating valve, the powder is normally transported to the target bin; S7. After the powder is transported to the target bin, the gas is initially filtered through the vent filter. Most of the powder will remain inside the vent filter. Then the gas with fine powder enters the recovery dust collector for re-filtration. The filtered gas is pressurized by the compressor and enters the state of pneumatic conveying powder again.

[0012] The present invention provides a powder pneumatic conveying system and a conveying method thereof using gas circulation, which realizes the reuse of nitrogen and reduces the nitrogen consumption of the conveying device; and the process uses a transmitter for continuous conveying, avoids intermittent conveying using a sending tank, ensures that the conveying process is continuous, stable and continuous, ensures the normal operation of the compressor, and avoids bringing impact loads to the compressor.

[0013] The present invention can continue to operate stably when powder exists in the finished product bin or the target bin is not full. Nitrogen is reused during the transportation process, which improves the utilization rate of nitrogen, reduces the venting volume, and reduces the waste gas treatment volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Figure 1 is a diagram of the overall pneumatic conveying system of the present invention; Figure 2 This is a diagram of a single finished product warehouse conveying system of the present invention; Figure 3 This is a diagram of the connection system between the finished product bin and the compressor of the present invention; Figure 4 It is a diagram of the dust recovery and removal system of the present invention.

[0015] In the figure: supplementary gas regulating valve 1; recovery buffer tank 2; vent filter 3; target warehouse 4; overpressure vent regulating valve 5; compressor inlet switch valve 6; compressor 7; powder feed switch valve 8; compressor outlet valve 9; buffer opening valve 10; gas buffer tank 11; branch main valve 12; pipe cleaning branch valve 13; first pneumatic regulating valve 14; second pneumatic regulating valve 15; inlet sender valve 16; outlet sender valve 17; outlet switch valve 18; finished product warehouse 19; recovery dust collector 20; gas supplementary inlet 21; buffer tank switch valve 22. DETAILED DESCRIPTION

[0016] Example 1 like Figures 1 to 4 As shown, a pneumatic conveying system for powders is realized by utilizing gas circulation, wherein a gas supplementary inlet 21 is connected to a recovery dust collector 20 and a recovery buffer tank 2, the recovery dust collector 20 is connected to the recovery buffer tank 2, the recovery buffer tank 2 is connected to the air inlets of multiple compressors 7, the air outlets of the compressors 7 are connected to multiple parallel finished product bins 19 through a gas buffer tank 11, the finished product bins 19 are connected to a target bin 4, and the target bin 4 is connected to the recovery dust collector 20 through a venting filter 3 to form a circulation.

[0017] The gas replenishment inlet 21 is connected to the recovery dust collector 20 and the recovery buffer tank 2, and the recovery dust collector 20 and the recovery buffer tank 2 are connected to each other, forming a basic framework for gas recovery and reuse. The recovery buffer tank 2 is a core transfer component, which is connected to the air inlets of multiple compressors 7. The air outlets of the compressors 7 are connected to multiple parallel finished product warehouses 19 through the gas buffer tank 11. The finished product warehouses 19 lead to the target warehouse 4. The target warehouse 4 is connected to the recovery dust collector 20 through the vent filter 3, forming a complete closed-loop circulation system, ensuring that nitrogen is continuously recycled during the powder conveying process, reducing nitrogen consumption and waste gas emissions.

[0018] In the preferred embodiment, the gas replenishment inlet 21 is connected to the recovery buffer tank 2 through the replenishment gas regulating valve 1, and a buffer tank switch valve 22 is provided between the recovery dust collector 20 and the recovery buffer tank 2. The buffer tank switch valve 22 acts as a "dispatcher" during the system operation stage. In the early gas replenishment stage of system startup, this valve is closed to prevent impurities, dust or unstable airflow that may exist in the recovery dust collector 20 from interfering with the gas replenishment process of the recovery buffer tank 2; when the system is running stably, especially in the gas recovery link after the powder conveying is completed, the valve is opened to allow the gas that has been initially filtered by the vent filter 3 and purified again by the recovery dust collector 20 to flow back smoothly to the recovery buffer tank 2, thereby maximizing the gas recycling, while avoiding mutual interference of airflows under different system working conditions, and ensuring that the functions of each link are independent and coordinated.

[0019] In the preferred embodiment, multiple compressors 7 are arranged in parallel, a compressor inlet switch valve 6 is provided between the recovery buffer tank 2 and the multiple compressors 7, and the multiple compressors 7 are connected to the gas buffer tank 11 through a buffer opening valve 10.

[0020] The parallel setting gives the system multiple safeguards and flexible deployment capabilities. First, if a compressor fails suddenly, the remaining compressors can take over to maintain the basic operation of the system, greatly reducing the probability and loss of downtime for maintenance and improving overall reliability. Second, according to the scale and difficulty of the conveying task, the number of operating compressors can be flexibly increased or decreased to achieve energy saving, efficiency improvement and precise adaptation. The compressor inlet switch valve 6 controls the compressor intake rhythm, and opens or closes the specific compressor intake channel according to the working conditions; the buffer opening valve 10 effectively buffers the sudden changes in the compressor outlet pressure and flow, smoothes the impact of airflow, ensures stable gas delivery to the gas buffer tank 11, and accurately supplies energy to the finished product warehouse, ensuring smooth and continuous power for powder conveying.

[0021] In the preferred embodiment, the recovery buffer tank 2 is connected to the buffer opening valve 10 through the overpressure venting regulating valve 5. The overpressure venting regulating valve 5 is the "guardian" of system safety. When the pressure of the recovery buffer tank 2 approaches or exceeds the safety threshold due to excessive gas replenishment, compressor abnormality and other factors, this valve automatically opens the pressure relief channel, accurately releases excess gas to the downstream safety area of ​​the buffer opening valve 10 according to the preset pressure value, strictly controls the system pressure within the safety range, and comprehensively prevents equipment damage, leakage and even explosion risks caused by overpressure, and builds a solid safety line for the stable operation of the system.

[0022] In the preferred embodiment, the gas buffer tank 11 is connected to the top air inlet of one of the finished product bins 19 through the branch main valve 12, and the bottom discharge port of the finished product bin 19 is connected to the target bin 4 through the powder feed switch valve 8.

[0023] In the preferred embodiment, three pipelines are connected in parallel between the branch main valve 12 and the powder feed switch valve 8, and a pigging branch valve 13 is provided on the first pipeline at the top of the three pipelines; A first pneumatic regulating valve 14 is provided on the middle pipeline, and an inlet and outlet valve 16 is provided between the first pneumatic regulating valve 14 and the parallel pipeline of the pigging branch valve 13; A second pneumatic regulating valve 15 is provided on the lowermost pipeline; An outlet valve 17 is provided between the three pipeline main pipes and the powder feed switch valve 8 .

[0024] The branch main valve 12 is like a "commander", accurately dispatching the gas in the gas buffer tank 11 to the target finished product warehouse 19, opening and closing it according to the transportation task, and preventing gas from flowing in and out of control. The powder feed switch valve 8 strictly controls the discharge of the finished product warehouse 19 to ensure that the powder is transported to the target warehouse 4 in an orderly and quantitative manner to avoid blockage or loss of control. The three parallel pipelines each have their own functions: the cleaning branch valve 13 is activated during system maintenance or pipeline cleaning, and the cleaning medium is introduced to efficiently remove the accumulated materials and impurities in the pipe; the first pneumatic regulating valve 14 and the second pneumatic regulating valve 15 cooperate to finely adjust the conveying gas volume and flow rate according to factors such as powder characteristics, conveying distance, and target warehouse 4 pressure to achieve optimal conveying energy efficiency; the inlet and outlet transmitter valve 16 cooperates with the outlet transmitter valve 17 to guide the gas in and out of the transmitter in an orderly manner, build a stable pneumatic conveying field, overcome the problems of powder viscosity and agglomeration, and ensure smooth feeding. The valves work together to achieve continuous, stable, and precise pneumatic conveying of powder to the target warehouse 4.

[0025] In the preferred solution, the outlet at the lower end of the finished product bin 19 is provided with an outlet switch valve 18. The outlet switch valve 18 is the "metronome" of the outlet rhythm of the finished product bin 19. The system starts the conveying process, opens according to the command, and releases the powder in sequence and in appropriate amounts to match the conveying system capacity and the receiving capacity of the target bin 4; in case of failure, maintenance or specific process suspension requirements, the outlet is quickly closed and cut off to prevent powder leakage and spillage causing waste and pollution, ensuring that the system's discharge link is accurately controllable, safe and reliable, and flexibly responds to the needs of the entire production process.

[0026] The gas replenishment inlet 21 is connected to the recovery buffer tank 2 through the replenishment gas regulating valve 1. This regulating valve accurately controls the replenishment gas flow and pressure to maintain the system air pressure stable; a buffer tank switch valve 22 is set between the recovery dust collector 20 and the recovery buffer tank 2 to flexibly adjust the on and off of the two according to the system operation stage to ensure the orderly connection of each link.

[0027] Multiple compressors 7 are arranged in parallel, and a compressor inlet switch valve 6 is set between the recovery buffer tank 2 and the multiple compressors 7. The compressor 7 is connected to the gas buffer tank 11 by means of a buffer opening valve 10, and the recovery buffer tank 2 is connected to the buffer opening valve 10 through an overpressure venting regulating valve 5. The overpressure venting regulating valve 5 timely releases the pressure when the system pressure is too high to ensure the safe and stable operation of the equipment. The gas buffer tank 11 is connected to the top air inlet of one of the finished product warehouses 19 through the branch main valve 12, and the bottom outlet of the finished product warehouse 19 is connected to the target warehouse 4 by means of the powder feed switch valve 8. At the same time, three pipelines are connected in parallel between the branch main valve 12 and the powder feed switch valve 8. Each pipeline is equipped with a unique valve for collaborative operation, such as the cleaning branch valve 13, the first pneumatic regulating valve 14, the second pneumatic regulating valve 15, the inlet transmitter valve 16, the outlet transmitter valve 17, etc., to accurately control the powder conveying state and flow rate; the outlet at the lower end of the finished product warehouse 19 is equipped with an outlet switch valve 18 to strictly control the rhythm and quantity of powder discharge.

[0028] Example 2 Further illustrate with reference to Example 1, Figure 1-4 The structure shown in FIG. 1 includes: S1. Close the buffer tank switch valve 22 between the recovery dust collector 20 and the recovery buffer tank 2, open the compressor inlet switch valve 6 above the compressor 7, open the supplementary gas regulating valve 1 on the recovery buffer tank 2, and supplement gas to the recovery buffer tank 2 to 0.005-0.006MPa, and then adjust the supplementary gas regulating valve 1 to the automatic gas supply mode; S2, open the compressor outlet valve 9 below the compressor 7, start the compressor 7 and open the overpressure venting regulating valve 5 at the same time to ensure the stable operation of the compressor 7; S3, adjust the pressure reducing valve from the compressor 7 to the gas buffer tank 11 to reduce the pressure to 0.2-0.5MPa, and open the buffer opening valve 10; S4, determine to transport the powder in the finished product warehouse 19 to the target warehouse 4, close the main valve of the gas branch, and open the main valve 12 of the branch that needs to transport the powder; S5, open the branch main valve 12, the cleaning branch valve 13, the inlet sender valve 16, the outlet sender valve 17, and the powder feed switch valve 8 to replace the air in the pipeline; S6, after the replacement is completed, the pigging branch valve 13 is closed, the buffer tank switch valve 22 and the warehouse switch valve 18 are opened, and the powder initially enters the transmitter, and the output of the first pneumatic regulating valve 14 and the second pneumatic regulating valve 15 is adjusted to realize the normal delivery of the powder to the target warehouse 4; S7. After the powder is transported to the target bin 4, the gas is initially filtered through the vent filter 3. Most of the powder will remain inside the vent filter 3. Then the gas with fine powder enters the recovery dust collector 20 for re-filtration. The filtered gas is pressurized by the compressor 7 and enters the state of pneumatically conveying the powder again.

[0029] Example 3 Further illustrate with reference to Examples 1-2, Figure 1-4 The structure shown: 1. Key system pressure data Recovery buffer tank gas replenishment pressure: Add gas to the recovery buffer tank 2 to 0.005 - 0.006MPa. This pressure value provides suitable air intake conditions for the initial start-up of the system, ensures stable air intake of the subsequent compressor, avoids insufficient air intake due to low pressure or impact on the equipment due to excessive pressure, and lays the foundation for stable transportation.

[0030] Pressure reduction range from compressor to gas buffer tank: adjust the pressure reducing valve from compressor 7 to gas buffer tank 11 to reduce the pressure to 0.2 - 0.5MPa. Through this precise pressure reduction, it can adapt to the pressure bearing and powder fluidization characteristics of finished product warehouse 19 and subsequent transportation pipelines. Reasonable pressure range can effectively promote powder fluidization and suspension, form a stable material-gas mixed flow, reduce pipeline wear and blockage risks, ensure transportation continuity, and create conditions for improving transportation efficiency.

[0031] 2. Relationship between conveying process characteristics and efficiency Advantages of continuous conveying: Abandon intermittent conveying by the sending tank and adopt the continuous conveying mode of the sender. Intermittent conveying has frequent start and stop, loading and unloading idling periods, resulting in low equipment utilization, energy waste and easy to cause system pressure fluctuations, interfering with the stable conveying state of powder. Continuous conveying eliminates such drawbacks, keeps the conveying uninterrupted, maintains the stability of system pressure and air flow speed, and makes the powder evenly and stably transported to the target bin 4, increasing the conveying volume per unit time and greatly enhancing the overall conveying efficiency.

[0032] Gas recycling efficiency enhancement: This system constructs a complete gas circulation path, and the gas is recycled from the target bin 4 through the vent filter 3, the recovery dust collector 20, the recovery buffer tank 2 and other links. Recycling reduces the amount of nitrogen supply, maintains the stability of the system air pressure, avoids system fluctuations and shutdown adjustments caused by frequent gas replenishment, ensures the continuity of the conveying process, and indirectly improves the conveying efficiency. Compared with the traditional non-circulating system, there is no waste of gas venting and frequent gas replenishment, the effective operation time is extended, and the stable air pressure ensures the constant power of powder conveying, which improves the conveying efficiency from multiple dimensions of energy utilization and operation stability.

[0033] The article does not involve explicit mathematical formulas for directly calculating key indicators such as the efficiency of pneumatic conveying of powders. However, from a principle perspective, a potential formula relationship can be derived: 1. Transmission power correlation formula According to the ideal gas state equation ( For pressure, is the volume, is the amount of substance, is the universal gas constant, is the temperature). In the compressor link, such as the process from the recovery buffer tank 2 to the gas buffer tank 11, the inlet pressure is known. (Recovery buffer tank pressure, set to Convert to SI units ), intake volume (The effective volume of the recovery buffer tank is set to ), outlet pressure (Gas buffer tank pressure after decompression Right now )、Outlet volume (The total volume of the gas buffer tank after the effective volume is connected to the pipeline is set as ), assuming the temperature Constant, we can get: ; ; ; This formula shows that the compressor achieves volume change by changing the gas pressure, generating power to transport the powder. In pneumatic conveying, the pressure energy is converted into the kinetic energy of the powder and work to overcome the resistance of the pipeline, providing a stable power source for continuous conveying and ensuring that the powder flows in the pipeline at a stable speed and state, which is crucial to the conveying efficiency. , After confirmation, Precise control and adjustable , and then adapt to different conveying distances and powder flow requirements to optimize the conveying efficiency.

[0034] 2. Flow Control Formula In the delivery branch from the finished product warehouse 19 to the target warehouse 4, the flow coefficient of the first pneumatic regulating valve 14 is set to , the opening is ; The flow coefficient of the second pneumatic regulating valve (15) is , the opening is ; Total pipeline flow The relationship with the regulating valve can be approximated as: ; in , To correspond to the pressure difference between upstream and downstream of the regulating valve, is the gas density. This formula shows that the gas volume can be precisely controlled by adjusting the valve opening, and the powder velocity and flow rate can be precisely adjusted under different working conditions (such as powder characteristics, conveying distance, target bin pressure changes). A stable and appropriate flow rate ensures that the powder is evenly suspended and conveyed in the pipeline, preventing sedimentation and blockage, and improving conveying continuity and efficiency. If the conveying distance increases, the pressure can be increased. , promote , ensuring that the powder is delivered to the target warehouse on time and in sufficient quantity, maintaining the overall stable transportation efficiency.

[0035] The above embodiments are only preferred technical solutions of the present invention and should not be regarded as limiting the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A system for pneumatically conveying powder materials using air circulation, characterized in that: The gas replenishment inlet (21) is connected to the recovery dust collector (20) and the recovery buffer tank (2), the recovery dust collector (20) is connected to the recovery buffer tank (2), the recovery buffer tank (2) is connected to the air inlets of a plurality of compressors (7), the air outlets of the compressors (7) are connected to a plurality of parallel finished product bins (19) through the gas buffer tank (11), the finished product bins (19) are connected to the target bin (4), and the target bin (4) is connected to the recovery dust collector (20) through the vent filter (3) to form a circulation.

2. According to claim 1, a system for pneumatic conveying of powder materials using air circulation is characterized in that: The gas replenishment inlet (21) is connected to the recovery buffer tank (2) through the replenishment gas regulating valve (1), and a buffer tank switch valve (22) is provided between the recovery dust collector (20) and the recovery buffer tank (2).

3. According to claim 1, a system for pneumatic conveying of powder materials using air circulation is characterized in that: The plurality of compressors (7) are arranged in parallel, a compressor inlet switch valve (6) is provided between the recovery buffer tank (2) and the plurality of compressors (7), and the plurality of compressors (7) are connected to the gas buffer tank (11) via a buffer opening valve (10).

4. The system for pneumatically conveying powder materials by utilizing air circulation according to claim 3, characterized in that: The recovery buffer tank (2) is connected to the buffer opening valve (10) via the overpressure venting regulating valve (5).

5. According to claim 1, a system for pneumatic conveying of powder materials using air circulation is characterized in that: The gas buffer tank (11) is connected to the top air inlet of one of the finished product bins (19) via the branch main valve (12), and the bottom discharge port of the finished product bin (19) is connected to the target bin (4) via the powder feed switch valve (8).

6. The system for pneumatically conveying powder materials by utilizing air circulation according to claim 5, characterized in that: There are three pipelines connected in parallel between the branch main valve (12) and the powder feed switch valve (8), and a cleaning branch valve (13) is provided on the first pipeline at the top of the three pipelines; A first pneumatic regulating valve (14) is provided on the middle pipeline, and an inlet and outlet valve (16) is provided between the first pneumatic regulating valve (14) and the pipeline parallel to the pigging branch valve (13); A second pneumatic regulating valve (15) is provided on the lowermost pipeline; An outlet valve (17) is provided between the three pipeline main pipes and the powder material feed switch valve (8).

7. The system for pneumatically conveying powder materials by utilizing air circulation according to claim 5, characterized in that: A discharge opening and closing valve (18) is provided at the discharge port at the lower end of the finished product bin (19).

8. A method for conveying powder materials by using air circulation to realize a pneumatic conveying system according to any one of claims 1 to 7, characterized in that: The method includes: S1. Close the buffer tank switch valve (22) between the recovery dust collector (20) and the recovery buffer tank (2), open the compressor inlet switch valve (6) above the compressor (7), open the supplementary gas regulating valve (1) on the recovery buffer tank (2), and add gas to the recovery buffer tank (2) to a pressure of 0.005-0.006 MPa, and then adjust the supplementary gas regulating valve (1) to an automatic gas supply mode; S2, opening the compressor outlet valve (9) below the compressor (7), starting the compressor (7) and simultaneously opening the overpressure venting regulating valve (5) to ensure stable operation of the compressor (7); S3, adjusting the pressure reducing valve from the compressor (7) to the gas buffer tank (11) to reduce the pressure to 0.2-0.5 MPa, and opening the buffer opening valve (10); S4, determining to transport the powder in the finished product bin (19) to the target bin (4), closing the main valve of the gas branch, and opening the main valve of the branch to which the powder needs to be transported (12); S5, open the branch main valve (12), the cleaning branch valve (13), the inlet sender valve (16), the outlet sender valve (17), and the powder feed switch valve (8) to replace the air in the pipeline; S6, after the replacement is completed, the pigging branch valve (13) is closed, the buffer tank switch valve (22) and the bin switch valve (18) are opened, and the powder initially enters the transmitter. By adjusting the output of the first pneumatic regulating valve (14) and the second pneumatic regulating valve (15), the powder is normally transported to the target bin (4); S7. After the powder is transported to the target bin (4), the gas is initially filtered through the vent filter (3). Most of the powder will remain inside the vent filter (3). Then, the gas containing fine powder enters the recovery dust collector (20) for further filtration. The filtered gas is pressurized by the compressor (7) and enters the state of pneumatically conveying the powder again.

Images