A method and system for biomass powder transportation experiment

Abstract

The present application provides a kind of biomass powder conveying experimental method and system, belong to biomass material conveying technical field, it can at least partially solve the problem that existing system cannot quantitatively analyze the influence of various variables on biomass powder conveying characteristics, the present application includes experimental method and matching system, can independently adjust air flow, temperature and material conveying concentration.Matching system is monitored by setting main road, bypass and powder circulation loop, real-time monitoring working condition parameters with detection unit;While integrating air lock, explosion door, material level meter, discharge port and other auxiliary structures, effectively prevent air backflow, pipeline blockage and dust explosion.The present application is flexible, material can be recycled, safe and stable, can carry out multiple control experiments, accurately collect experimental data, provide strong support for biomass powder conveying characteristics research.

Description

Technical Field

[0001] This invention belongs to the field of biomass material conveying technology, specifically relating to an experimental method and system for conveying biomass powder. Background Technology

[0002] Currently, the coupling of coal-fired power units with biomass power generation has become a major path for reducing carbon emissions in thermal power units. There are two main routes for coupling biomass with coal-fired power units: direct combustion and gasification. In both routes, biomass must be fed into the power plant boiler or biomass gasifier in powder form of varying particle sizes. During the transportation of biomass powder, in-depth research is needed on parameters such as biomass type, moisture content, temperature, pressure, flow rate, concentration, system resistance, collection efficiency, weighing, feeding stability, and material mixing characteristics. This research aims to establish a reliable design basis for biomass powder transportation in engineering modifications and requires the design of an experimental device that meets the requirements for biomass powder storage, transportation, weighing, collection, and adjustable medium parameters.

[0003] Currently, the industry lacks an integrated, multi-parameter adjustable dedicated experimental platform, which makes it impossible to systematically and quantitatively analyze the impact of various variables on the transport characteristics of biomass powder. As a result, the selection of transport pipelines, feeding parameters, and configuration of separation equipment during engineering transformation largely rely on experience in coal powder transportation, resulting in large deviations in design parameters. This not only increases the cost of unit transformation but also easily leads to problems such as unstable unit operation and high energy consumption during transportation.

[0004] Therefore, an experimental method and system for transporting biomass powder is proposed. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and to provide an experimental method and system for transporting biomass powder.

[0006] One aspect of the present invention provides an experimental method for transporting biomass powder, implemented based on a transport system having a main transport path, a bypass transport path, a powder supply path, a powder recovery path, and an external air supply path, comprising the following steps: S1. Based on the preset experimental conditions, determine the target range of conveying medium flow rate, medium temperature, pipeline pressure, and powder conveying concentration, and complete system testing and material reserve verification to meet the experimental conditions. Connect the main conveying path, establish an empty circulating airflow, and adjust the airflow supply parameters, medium heating parameters, and external air supply parameters according to the collected conveying medium flow rate, medium temperature, and pipeline pressure data so that the empty circulating airflow reaches the target range. S2. Connect the powder supply path and the powder recovery path, and adjust the powder supply parameters so that the biomass powder enters the unloaded circulating airflow to form a gas-solid two-phase transport condition. S3. Under the gas-solid two-phase transport condition, collect the flow rate of the transport medium, the medium temperature, the pipeline pressure, and the powder supply amount, and determine the biomass powder transport characteristic data in combination with the powder recovery amount; and adjust the air supply parameters, the medium heating parameters, the external air supply parameters, and the powder supply parameters according to the preset experimental conditions to repeatedly form the no-load circulating airflow, the gas-solid two-phase transport condition, and the biomass powder transport characteristic data; and when an abnormal condition occurs, first stop the powder supply, and switch to the bypass transport path after the residual powder is discharged; at the end of the experiment, first stop the powder supply, then reduce the operating parameters and shut down the machine.

[0007] Furthermore, during the experiment, the flow rate, temperature, pipeline pressure, and powder concentration of the conveying medium were adjusted by regulating the airflow supply parameters, medium heating parameters, external air supply parameters, and powder supply parameters respectively.

[0008] Furthermore, during the experiment, pipeline pressure and medium temperature data were collected at the node after medium heating and before gas-solid mixing, and at the node after gas-solid mixing, the transport medium flow rate, pipeline pressure, and medium temperature data were collected. Combining the test data of the no-load pure airflow condition and the gas-solid two-phase transport condition, the pipeline resistance, temperature loss, and material transport efficiency under different control conditions were calculated. The influence of three types of variables—air volume, medium heating temperature, and powder supply rate—on the transport characteristics of biomass powder and the gas-solid separation effect was quantitatively analyzed.

[0009] Another aspect of the present invention provides a biomass powder transportation experimental system, said system for implementing the above-described biomass powder transportation experimental method, comprising: The fan, heater, and mixer are connected sequentially by pipelines along the airflow direction; The main conveying unit includes at least one cyclone separator, a bag filter, and a manifold; the at least one cyclone separator and the bag filter are connected in series along the airflow conveying direction; the air inlet of the at least one cyclone separator is connected to the output of the mixer through a connecting pipe; the air outlet of the bag filter is connected to the air inlet of the fan through the manifold; the manifold is provided with an external air supply port, which is used to supply gas to the manifold to adjust the pipeline pressure and total airflow. The bypass conveying unit includes a bypass pipeline whose two ends are respectively connected to the discharge port of the mixer and the inlet of the manifold pipeline; A biomass powder conveying unit includes a collecting pipeline connected to the outlet of the at least one cyclone separator and a bag filter, a biomass silo connected to the outlet of the collecting pipeline, and a weighing feeder connected to the outlet of the biomass silo; the outlet of the weighing feeder is connected to the powder inlet of the mixer. The detection unit includes multiple pressure acquisition units and temperature acquisition units respectively disposed on the pipeline between the heater and the mixer and on the connecting pipeline, as well as a flow acquisition unit disposed on the connecting pipeline.

[0010] Furthermore, a first electric valve is provided on the connecting pipe between the output port of the mixer and the air inlet of the at least one cyclone separator; a second electric valve is provided between the air outlet of the bag filter and the manifold; and a third electric valve and a fourth electric valve are respectively provided at the air inlet and air outlet of the bypass pipe to regulate the transport path of the transport experimental system.

[0011] Furthermore, the top of the biomass silo is provided with a feed inlet, and a level gauge is installed inside.

[0012] Furthermore, a first manual valve is provided at the discharge port of the weighing feeder, a second manual valve is provided at the discharge port of the biomass silo, and a third manual valve is provided at the external air supply port of the manifold.

[0013] Furthermore, a discharge port is provided on the pipeline connecting the weighing feeder to the first manual valve.

[0014] Furthermore, airlocks are installed at the discharge ports of both the at least one cyclone separator and the bag filter.

[0015] Furthermore, explosion-proof doors are provided on the at least one cyclone separator, the bag filter, the connecting pipeline, the bypass pipeline, the collecting pipeline, and the manifold.

[0016] The beneficial effects of this invention are as follows: 1. The conveying pipeline of the present invention forms a closed-loop powder circulation loop. The separated biomass powder can be returned to the silo for reuse, reducing the loss of experimental materials. At the same time, it is equipped with a flow acquisition unit, a temperature acquisition unit, a pressure acquisition unit, and an adjustable power fan, heater, and weighing feeder to achieve independent control of multiple parameters such as temperature, flow rate, and powder concentration of the conveying medium, meet the needs of conveying experiments under different working conditions, and has a wide coverage of experimental data. 2. This invention, by setting up a dual-air path structure with an independent main conveying path and a bypass conveying path, enables flexible switching between multiple modes such as normal transport experiment, emergency working condition avoidance or no-load control experiment. In the event of a sudden failure, it can quickly isolate the powder supply path, powder recovery path and main conveying path, and smoothly complete the air path switching, effectively improving the safety and adaptability of the device operation. 3. This invention, through clearly defined zones for each valve and device, standardizes the operation process. Start-up, shutdown, bypass switching, and shutdown are all performed according to the standard procedures, which can effectively avoid problems such as sudden changes in wind pressure and temperature and backflow of airflow, and reduce the adverse effects of human operation errors on experiments and equipment. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the steps of an experimental method for transporting biomass powder according to a specific embodiment of the present invention. Figure 2 This is a schematic diagram of the component connections of a biomass powder transportation experimental system according to a specific embodiment of the present invention.

[0018] The components include: 1. Mixer; 2. First electric valve; 3. Cyclone separator; 4. Bag filter; 5. Second electric valve; 6. Third electric valve; 7. Bypass pipeline; 8. Fourth electric valve; 9. First manual valve; 10. Weighing feeder; 11. Second manual valve; 12. Biomass silo; 13. Collection pipeline; 14. Heater; 15. Fan; 16. Flow acquisition unit; 17. Pressure acquisition unit; 18. Temperature acquisition unit; 19. Third manual valve; 20. Feed inlet; 21. Level gauge; 22. Discharge outlet; 23. Airlock; 24. Manifold pipeline. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Combination Figure 1As shown, the biomass powder transportation experimental method provided by the specific embodiment of the present invention is implemented based on a transportation system having a main conveying path, a bypass conveying path, a powder supply path, a powder recovery path, and an external air supply path, including the following steps: S1, according to preset experimental conditions, determine the target range of conveying medium flow rate, medium temperature, pipeline pressure, and powder conveying concentration, and complete system testing and material reserve verification to meet the experimental conditions; connect the main conveying path to establish an empty-load circulating airflow; and adjust the airflow supply parameters, medium heating parameters, and external air supply parameters according to the collected data of conveying medium flow rate, medium temperature, and pipeline pressure to make the empty-load circulating airflow reach the target range; S2, connect the powder supply path and the powder recovery path. The powder supply parameters are adjusted to allow biomass powder to enter the unloaded circulating airflow, forming a gas-solid two-phase transport condition. S3: Under the gas-solid two-phase transport condition, the flow rate, temperature, pipeline pressure, and powder supply amount of the transporting medium are collected, and the biomass powder transport characteristic data are determined in conjunction with the powder recovery amount. Furthermore, the airflow supply parameters, medium heating parameters, external air supply parameters, and powder supply parameters are adjusted according to the preset experimental conditions to repeatedly form the unloaded circulating airflow, the gas-solid two-phase transport condition, and the biomass powder transport characteristic data. In case of abnormal conditions, the powder supply is stopped first, and after the residual powder is discharged, the system switches to the bypass transport path. At the end of the experiment, the powder supply is stopped first, and then the operating parameters are reduced before shutdown.

[0021] Furthermore, during the experiment, the flow rate, temperature, pipeline pressure, and powder concentration of the conveying medium were adjusted by regulating the airflow supply parameters, medium heating parameters, external air supply parameters, and powder supply parameters respectively.

[0022] Furthermore, during the experiment, pipeline pressure and medium temperature data were collected at the node after medium heating and before gas-solid mixing, and at the node after gas-solid mixing, the transport medium flow rate, pipeline pressure, and medium temperature data were collected. Combining the test data of the no-load pure airflow condition and the gas-solid two-phase transport condition, the pipeline resistance, temperature loss, and material transport efficiency under different control conditions were calculated. The influence of three types of variables—air volume, medium heating temperature, and powder supply rate—on the transport characteristics of biomass powder and the gas-solid separation effect was quantitatively analyzed.

[0023] Combination Figure 2As shown, in one embodiment, specifically, in steps S1 and S2, before the system is officially put into operation, the first electric valve 2, the second electric valve 5, the third electric valve 6, the fourth electric valve 8, the first manual valve 9, the second manual valve 11, and the third manual valve are kept in the fully closed state. Power is supplied to the blower 15, the heater 14, and the detection unit for a power-on test. It is checked that the flow acquisition unit 16, the pressure acquisition unit 17, and the temperature acquisition unit 18 are all in normal working condition. Simultaneously, the detection data of the level gauge 21 is checked to ensure that the material level in the biomass silo 12 meets the preset requirements of this experiment. The experiment begins by opening the first electric valve 2 and the second electric valve 5 on the main conveying path, as well as the third manual valve 19 at the air inlet of the manifold 24. Then, the blower 15 is started to establish an unloaded circulating airflow. The detection unit collects the flow rate, temperature, and pressure data of the airflow in the conveying pipeline in real time. Based on the detection results, the flow rate of the blower 15 and the operating power of the heater 14 are gradually adjusted until all detection data reach the preset experimental values. The weighing feeder 10 is started in sequence, and the first manual valve 9 and the second manual valve 11 are opened to allow the biomass powder to enter the pipeline and participate in the conveying experiment.

[0024] Specifically, in step S3, during the experiment, the operating speed of the fan 15, the heating power of the heater 14, and the operating speed of the weighing feeder 10 are adaptively adjusted according to the actual preset experimental operating parameters. This corresponds to controlling the flow rate of the conveying medium, the heating temperature, and the feeding concentration of the biomass powder. At the same time, the opening of the third manual valve 19 at the air inlet of the manifold 24 is finely adjusted to introduce ambient temperature air, balance the overall pressure and total air volume inside the pipeline, and counteract the air pressure imbalance caused by changes in powder concentration and heating in the medium. This maintains the stability of the entire pipeline operating conditions and achieves the balance of the conveying medium temperature, flow rate, and biomass powder concentration. Independent control allows for the comparison of biomass powder transport under different operating conditions. If an emergency occurs in the pipeline due to abnormal pressure, dust accumulation, or overheating, or if the experimental conditions require switching to a bypass transport path and no biomass powder is needed for a no-load control experiment, the bypass switching operation is performed. First, the second manual valve 11 at the outlet of the biomass silo 12 is closed to cut off the biomass powder supply. After the remaining biomass powder in the pipeline has been transported, the weighing feeder 10 is stopped. Then, the first manual valve 9 at the inlet of the mixer 1 is closed to isolate the biomass powder transport path, preventing high-temperature, high-pressure airflow from backflowing and damaging the feeding equipment, and maintaining the main transport path for a period of time. After emptying the system pipeline of residual biomass powder and stabilizing the pipeline air pressure and temperature, open the third electric valve 6 and the fourth electric valve 8 to open the bypass air duct, and simultaneously close the first electric valve 2 and the second electric valve 5 to cut off the main conveying air path, allowing the high-temperature airflow to flow directly back to the blower 15 through the bypass pipeline 7, completing a smooth switch from the main path to the bypass operation, avoiding equipment damage and dust safety accidents; when the experiment ends and the system needs to be shut down, operate step by step in the reverse order of system commissioning to achieve a smooth shutdown of the device, avoiding problems such as sudden changes in air pressure, material accumulation, and backflow of airflow; first close the second manual valve at the outlet of the biomass silo 12. 11. Cut off the powder supply. After the remaining powder in the pipeline has been completely conveyed, stop the weighing feeder 10 and close the first manual valve 9. Next, gradually reduce the power of the heater 14 until it reaches zero, turn off the heater 14, and slowly reduce the air volume of the fan 15 to avoid drastic fluctuations in pipeline temperature and air pressure. After the operating parameters, including the temperature, flow rate, and pressure in the pipeline, have been reduced and stabilized, close the first electric valve 2 and the second electric valve 5 of the main conveying unit. Finally, turn off the fan 15 and close the third manual valve 19 at the main air inlet, the third electric valve 6 corresponding to the bypass conveying unit, and the fourth electric valve 8 in sequence to complete the shutdown of the entire system.

[0025] In another embodiment, combined with Figure 2As shown, the present invention also provides a biomass powder transportation experimental system. The system is used to implement the above-described biomass powder transportation experimental method and includes: a fan 15, a heater 14, and a mixer 1 connected sequentially along the airflow direction; a main conveying unit including at least one cyclone separator 3, a bag filter 4, and a manifold 24; the at least one cyclone separator 3 and the bag filter 4 are connected in series along the airflow direction; the air inlet of the at least one cyclone separator 3 is connected to the output of the mixer 1 via a connecting pipe; the air outlet of the bag filter 4 is connected to the air inlet of the fan 15 via the manifold 24; the manifold 24 is provided with an external air supply port for supplying gas to the manifold 24 to regulate... Pipeline pressure and total air volume; bypass conveying unit, including a bypass pipeline 7 connected at both ends to the discharge port of the mixer 1 and the input port of the manifold 24 respectively; biomass powder conveying unit, including a collecting pipeline 13 connected to the discharge ports of at least one cyclone separator 3 and bag filter 4, a biomass silo 12 connected to the output port of the collecting pipeline 13, and a weighing feeder 10 connected to the discharge port of the biomass silo 12; the discharge port of the weighing feeder 10 is connected to the powder inlet of the mixer 1; detection unit, including multiple pressure acquisition units 17 and temperature acquisition units 18 respectively disposed on the pipeline between the heater 14 and the mixer 1 and on the connecting pipeline, and a flow acquisition unit 16 disposed on the connecting pipeline.

[0026] Furthermore, a first electric valve 2 is installed on the connecting pipe between the output port of the mixer 1 and the air inlet of the at least one cyclone separator 3; a second electric valve 5 is installed between the air outlet of the bag filter 4 and the manifold 24; and a third electric valve 6 and a fourth electric valve 8 are respectively installed at the air inlet and air outlet of the bypass pipe 7 to regulate the transport path of the transport experimental system. Furthermore, the top of the biomass silo 12 is provided with a feed inlet 20, and a level gauge 21 is installed inside.

[0027] Furthermore, a first manual valve 9 is provided at the discharge port of the weighing feeder 10, a second manual valve 11 is provided at the discharge port of the biomass silo 12, and a third manual valve 19 is provided at the external air supply port of the manifold 24.

[0028] In this embodiment, the system consists of three independent but coordinated conveying pipelines: a main conveying path, a bypass conveying path, and a powder recycling path. The powder recycling path includes a powder supply path and a powder recovery path. It also includes an external air supply path for replenishing ambient air to balance the overall pressure and total air volume inside the pipeline. Each path and its supporting equipment have a clear division of labor and work together to complete the entire process of biomass powder transportation.

[0029] Specifically, the main conveying path consists of a fan 15, a heater 14, a mixer 1, a first electric valve 2, at least one cyclone separator 3, a bag filter 4, a second electric valve 5, and a manifold 24 connected in sequence. This path is the main air path under normal experimental conditions. The fan 15 provides circulating conveying airflow, the heater 14 regulates the temperature of the airflow, and the mixer 1 ensures thorough mixing of hot air and biomass powder. The material-carrying airflow flows sequentially through each stage of cyclone separator 3 and bag filter 4 to complete gas-solid separation. The separated clean airflow returns to the air inlet of the fan 15 through the second electric valve 5, forming a closed loop, which can be used to conduct normal conveying experiments under different temperatures, air volumes, and powder concentrations.

[0030] Specifically, the bypass delivery path consists of the output end of mixer 1, the third electric valve 6, the bypass pipeline 7, the fourth electric valve 8, and the manifold 24. This path serves as an emergency channel and an unloaded control channel. After startup, it can cut off the main air path, allowing hot air to flow directly back to the fan 15 via the bypass pipeline 7, thus achieving unloaded operation of the system. It is mainly used for emergency emergency avoidance experiments, pipeline purging before equipment maintenance, and comparative experiments on the characteristics of pure airflow in the absence of powder.

[0031] Specifically, the powder recycling path consists of a biomass silo 12, a second manual valve 11, a weighing feeder 10, a first manual valve 9, a mixer 1, at least one cyclone separator 3, a bag filter 4, and a collecting pipeline 13, forming a closed loop. The biomass silo 12 is used to store experimental biomass powder. The second manual valve 11 controls the powder discharge. The weighing feeder 10 can precisely adjust the powder conveying rate and feed rate, thereby changing the powder concentration in the pipeline. The powder is fed into the mixer 1 by the weighing feeder 10 and mixed with hot air. The material-carrying airflow flows sequentially through each stage of the cyclone separator 3 and the bag filter 4. After the gas-solid mixture is separated, the separated powder flows back to the biomass silo 12 through the collecting pipeline 13, realizing powder recycling and reducing material loss.

[0032] Specifically, the external air supply path consists of the external air supply port of the manifold 24 and the third manual valve 19. By finely adjusting the opening of the third manual valve 19 at the air inlet of the manifold 24, ambient temperature air is supplied to balance the overall pressure and total air volume inside the pipeline, offsetting the air pressure imbalance caused by changes in powder concentration and heating in the medium, maintaining the stability of the entire pipeline operation, and realizing independent control of the temperature, flow rate and biomass powder concentration of the conveying medium, thus meeting the experimental requirements for biomass powder transportation comparison under different operating conditions.

[0033] Specifically, the flow acquisition unit 16, pressure acquisition unit 17, and temperature acquisition unit 18 accurately acquire airflow and medium parameters at key nodes within the system, providing core data for experimental data analysis and operational control. The flow acquisition unit 16 is installed on the connecting pipeline between the mixer 1 and the cyclone separator 3, monitoring the instantaneous and cumulative flow of the material-carrying airflow in real time, aiding in the study of the impact of airflow velocity on the transport efficiency of biomass powder. The pressure acquisition unit 17 dynamically captures pressure fluctuations within the pipeline, providing timely warnings of abnormal conditions such as pipeline blockage and airflow leakage. The temperature acquisition unit 18 is located at designated nodes in the pipeline between the heater 14 and the mixer 1, the connecting pipeline, and the manifold 24, continuously recording airflow temperature changes to ensure that temperature parameters remain stable within a preset range during the experiment. Each acquisition unit outputs real-time data for monitoring, recording, and subsequent analysis of the transport process.

[0034] Specifically, the biomass silo 12 serves as a dedicated powder storage and supply carrier for this experimental system. It primarily stores the biomass powder to be tested, ensuring a continuous and stable supply of experimental materials for the entire powder transport experiment. Operators can easily add sufficient biomass powder to the silo through the inlet 20, completing the loading operation conveniently. The integrated level gauge 21 inside the silo continuously collects the real-time level of the biomass powder and feeds the data back to the operator. This prevents material shortages and ensures the continuity of the experiment from occurring due to low material levels, while also preventing powder overflow and dust accumulation caused by excessively high levels. This, combined with the overall system, enables automated level monitoring, guaranteeing the long-term stable operation of the powder conveying unit.

[0035] Furthermore, a discharge port 22 is provided on the pipeline connecting the weighing feeder 10 to the first manual valve 9.

[0036] In this embodiment, the discharge port 22 is mainly used for equipment operation and maintenance and working condition cleaning. When the system is shut down or the experimental materials are changed, the residual biomass powder in the pipeline and weighing feeder 10 can be discharged through the discharge port 22 to avoid problems such as caking, dampness, and pipeline blockage caused by long-term powder retention. At the same time, during equipment maintenance and troubleshooting, the material in the pipeline section can also be emptied through the discharge port 22 to facilitate maintenance operations and ensure smooth pipeline transportation.

[0037] Furthermore, an airlock 23 is installed at the discharge port of the at least one cyclone separator 3 and the discharge port of the bag filter 4.

[0038] In this embodiment, the airlock 23 can isolate the internal and external airflow between the cyclone separator 3 and the bag filter 4 while ensuring the smooth discharge of collected dust. This prevents the system's circulating airflow from leaking out of the discharge port and disrupting the pipeline pressure balance. At the same time, it avoids backflow of external air from affecting the separation and dust removal effect, ensuring the overall air circuit operation is stable.

[0039] Furthermore, explosion-proof doors are provided on at least one cyclone separator 3, the bag filter 4, the connecting pipeline, the bypass pipeline 7, the collecting pipeline 13, and the confluence pipeline 24.

[0040] In this embodiment, explosion-proof doors, serving as safety pressure relief and protection components, are comprehensively deployed in the cyclone separator 3, bag filter 4, connecting pipelines, bypass pipelines 7, collecting pipelines 13, and manifolds 24. When a sudden pressure increase occurs inside the pipeline due to dust explosion, the explosion-proof doors can automatically open to relieve pressure, quickly releasing the high-pressure gas inside the pipeline. This prevents equipment and pipelines from deforming or rupturing due to overpressure, effectively reducing equipment damage and safety risks caused by explosions, and improving the safety and reliability of the entire experimental system.

[0041] In summary, the embodiments disclosed herein have at least the following technical effects: 1. The conveying pipeline of the present invention forms a closed-loop powder circulation loop. The separated biomass powder can be returned to the silo for reuse, reducing the loss of experimental materials. At the same time, it is equipped with a flow acquisition unit, a temperature acquisition unit, a pressure acquisition unit, and an adjustable power fan, heater, and weighing feeder to achieve independent control of multiple parameters such as temperature, flow rate, and powder concentration of the conveying medium, meet the needs of conveying experiments under different working conditions, and has a wide coverage of experimental data. 2. This invention, by setting up a dual air path structure with an independent main conveying path and a bypass conveying path, enables flexible switching between multiple modes such as normal transport experiment, emergency working condition avoidance or no-load control experiment. In the event of a sudden failure, it can quickly isolate the powder recycling return path from the main conveying path and smoothly complete the air path switching, effectively improving the safety and adaptability of the device operation. 3. This invention, through clearly defined zones for each valve and device, standardizes the operation process. Start-up, shutdown, bypass switching, and shutdown are all performed according to the standard procedures, which can effectively avoid problems such as sudden changes in wind pressure and temperature and backflow of airflow, and reduce the adverse effects of human operation errors on experiments and equipment.

[0042] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for transporting biomass powder, characterized in that, The implementation based on a transport system having a main conveying path, a bypass conveying path, a powder supply path, a powder recovery path, and an external air supply path includes the following steps: S1. Based on the preset experimental conditions, determine the target range of conveying medium flow rate, medium temperature, pipeline pressure, and powder conveying concentration, and complete system testing and material reserve verification to meet the experimental conditions. Connect the main conveying path, establish an empty circulating airflow, and adjust the airflow supply parameters, medium heating parameters, and external air supply parameters according to the collected conveying medium flow rate, medium temperature, and pipeline pressure data so that the empty circulating airflow reaches the target range. S2. Connect the powder supply path and the powder recovery path, and adjust the powder supply parameters so that the biomass powder enters the unloaded circulating airflow to form a gas-solid two-phase transport condition. S3. Under the gas-solid two-phase transport condition, collect the flow rate of the transport medium, the medium temperature, the pipeline pressure, and the powder supply amount, and determine the biomass powder transport characteristic data in combination with the powder recovery amount; and adjust the air supply parameters, the medium heating parameters, the external air supply parameters, and the powder supply parameters according to the preset experimental conditions to repeatedly form the no-load circulating airflow, the gas-solid two-phase transport condition, and the biomass powder transport characteristic data; and when an abnormal condition occurs, first stop the powder supply, and switch to the bypass transport path after the residual powder is discharged; at the end of the experiment, first stop the powder supply, then reduce the operating parameters and shut down the machine.

2. The experimental method for transporting biomass powder according to claim 1, characterized in that, During the experiment, the flow rate, temperature, pipeline pressure, and powder concentration of the conveying medium were adjusted by regulating the air supply parameters, medium heating parameters, external air supply parameters, and powder supply parameters respectively.

3. The experimental method for transporting biomass powder according to claim 1, characterized in that, During the experiment, pipeline pressure and medium temperature data were collected at the node after medium heating and before gas-solid mixing, and at the node after gas-solid mixing, the transport medium flow rate, pipeline pressure, and medium temperature data were collected. Combining the test data of the no-load pure airflow condition and the gas-solid two-phase transport condition, the pipeline resistance, temperature loss, and material transport efficiency under different control conditions were calculated. The influence of three types of variables—air volume, medium heating temperature, and powder supply rate—on the transport characteristics of biomass powder and the gas-solid separation effect was quantitatively analyzed.

4. A biomass powder transport experimental system, characterized in that, include: The fan, heater, and mixer are connected sequentially by pipelines along the airflow direction; The main conveying unit includes at least one cyclone separator, a bag filter, and a manifold; the at least one cyclone separator and the bag filter are connected in series along the airflow conveying direction; the air inlet of the at least one cyclone separator is connected to the output of the mixer through a connecting pipe; the air outlet of the bag filter is connected to the air inlet of the fan through the manifold; the manifold is provided with an external air supply port, which is used to supply gas to the manifold to adjust the pipeline pressure and total airflow. The bypass conveying unit includes a bypass pipeline whose two ends are respectively connected to the discharge port of the mixer and the inlet of the manifold pipeline; A biomass powder conveying unit includes a collecting pipeline connected to the outlet of the at least one cyclone separator and a bag filter, a biomass silo connected to the outlet of the collecting pipeline, and a weighing feeder connected to the outlet of the biomass silo; the outlet of the weighing feeder is connected to the powder inlet of the mixer. The detection unit includes multiple pressure acquisition units and temperature acquisition units respectively disposed on the pipeline between the heater and the mixer and on the connecting pipeline, as well as a flow acquisition unit disposed on the connecting pipeline.

5. The biomass powder transportation experimental system according to claim 4, characterized in that, A first electric valve is installed on the connecting pipe between the output port of the mixer and the air inlet of the at least one cyclone separator; a second electric valve is installed between the air outlet of the bag filter and the manifold; a third electric valve and a fourth electric valve are respectively installed at the air inlet and air outlet of the bypass pipe to regulate the transport path of the transport experimental system.

6. The biomass powder transportation experimental system according to claim 4, characterized in that, The biomass silo has a feed inlet at the top and a level gauge installed inside.

7. The biomass powder transportation experimental system according to claim 4, characterized in that, The weighing feeder is equipped with a first manual valve at its discharge port, the biomass silo is equipped with a second manual valve at its discharge port, and the manifold is equipped with a third manual valve at its external air supply port.

8. The biomass powder transportation experimental system according to claim 7, characterized in that, A discharge port is provided on the pipeline connecting the weighing feeder and the first manual valve.

9. The biomass powder transportation experimental system according to claim 4, characterized in that, An airlock is installed at the discharge port of at least one cyclone separator and at the discharge port of the bag filter.

10. The biomass powder transportation experimental system according to any one of claims 4 to 9, characterized in that, Explosion-proof doors are provided on at least one cyclone separator, the bag filter, the connecting pipeline, the bypass pipeline, the collecting pipeline, and the manifold.

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