Pneumatic conveying optimization control method and system based on conveying state recognition

Abstract

The invention discloses a pneumatic conveying optimization control method and system based on conveying state recognition, pneumatic conveying states comprise a dilute phase, a critical phase and a dense phase, and the method comprises the steps that calculation indexes are defined, and a pressure grading standard and a flow grading standard are set in the system design stage; a control unit of the system activates a sensor module after receiving a starting instruction, initializes key parameters, establishes an initial judgment reference and enters a conveying waiting state; the system enters a conveying state, and the control unit determines a current conveying mode according to an initial judgment benchmark and stores pressure and flow data collected in real time into a memory; after conveying is finished each time, according to the collected pressure and flow data, the pressure and the flow of the conveying peak section are taken out and converted into corresponding average values to be stored in a storage; and the control unit executes the control strategy according to the current conveying mode. The system has the characteristics that the stability of the system is improved, and the pipe is not easy to block.

Description

Technical Field

[0001] The present application relates to the technical field of pneumatic conveying, and in particular to a pneumatic conveying optimization control method and system based on conveying state identification. Background Art

[0002] Pneumatic conveying, also known as air flow conveying, utilizes the energy of air flow to transport granular materials along the direction of air flow in a closed pipe. It is a specific application of fluidization technology. The pneumatic conveying device has a simple structure and is easy to operate. It can be used for horizontal, vertical or inclined conveying. During the conveying process, physical operations such as heating, cooling, drying and air flow classification of materials or certain chemical operations can also be carried out simultaneously.

[0003] However, existing pneumatic conveying systems have the following defects: In the existing technology, many pneumatic conveying systems still rely on static, preset mode switching rules, or are adjusted based solely on experience, which makes it difficult to cope with the influence of changing material properties, pipeline conditions and environmental factors, resulting in low conveying efficiency, frequent pipe blockages, and even possible production interruptions. Summary of the Invention

[0004] One object of the present application is to provide a pneumatic conveying optimization control method and system that can automatically adjust the conveying mode based on conveying state identification.

[0005] To achieve the above objectives, the technical solution adopted in this application is: a pneumatic conveying optimization control method based on conveying state identification, where the pneumatic conveying states include dilute phase, critical phase and dense phase, comprising the following steps: S100, define calculation indicators, establish pressure classification standards and flow classification standards during the system design phase, and plan the pressure classification standards and flow classification standards into three levels: low, medium, and high according to the fluctuation range of pressure and flow respectively; S200, after receiving the start command, the control unit of the system activates the sensor module, initializes key parameters, establishes an initial judgment benchmark, and enters a waiting state for delivery; S300, the system enters the delivery state, the control unit determines the current delivery mode based on the initial judgment standard, and stores the real-time collected pressure and flow data into the memory; S400, after each delivery is completed, the pressure and flow rate of the delivery peak section are obtained based on the collected pressure and flow rate data, and converted into corresponding average values ​​and stored in the memory; S500, according to the current conveying mode, the control unit executes the control strategy, the control strategy is based on the level of the average pressure of one or two consecutive conveying peak segments, combined with the level change trend or level distribution ratio of the average flow rate of the conveying peak segment in the recent historical conveying records, to identify and analyze the current pneumatic conveying state, and enable the control unit to switch the conveying mode, adjust the conveying mode or maintain the current conveying mode.

[0006] In some embodiments, when the current delivery mode is dilute phase, step S500 includes: S501: The measured data shows that the average pressure of the peak delivery section is at a low level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low, or the preset proportion of historical delivery flow rates are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to be switched to a dense phase mode and stores the mode switching record in the memory. S502: The measured data shows that the average pressure of the delivery peak section is at a medium level. Observe the recent historical delivery records. If the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or if the flow rates in a preset proportion of historical delivery records are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to switch to a critical mode while attempting to move closer to a dense phase mode, and stores the mode switching record in the memory. S503, if two consecutive measurement data show that the average pressure of the delivery peak section is at a high level, the system will clear the previous mode switching history data and re-record it, indicating that the current pneumatic conveying state is in a dilute phase state, and the system maintains the current mode without switching.

[0007] In some embodiments, when the current delivery mode is dense phase, step S500 includes: S504: The measured data shows that the average pressure of the peak delivery section is at a low level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low, or the preset proportion of historical delivery flow rates are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state, and the system maintains the current state. S505: The measured data shows that the average pressure of the delivery peak section is at a medium level. Observing the recent historical delivery records, if the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or if the flow rates in a preset proportion of historical delivery records are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state and is closer to a critical state, and the system maintains the current state. S506, if two consecutive measurement data show that the average pressure of the delivery peak section is at a high level, the system will clear the previous mode switching history data and re-record it, and allow the delivery mode to be actively switched to the critical mode; S507: If pipe blockage occurs twice in succession, the system will clear the previous mode switching history data and re-record it, and allow the conveying mode to be actively switched to the dilute phase mode.

[0008] In some embodiments, when the current delivery mode is critical, step S500 includes: S508: The measured data shows that the average pressure of the delivery peak section is at a low level. Observe the recent historical delivery records. If the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or the flow rates in a preset proportion of historical delivery records are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to be actively switched to a dense phase mode and stores the mode switching record in the memory. S509: The measured data shows that the average pressure of the delivery peak section is at a medium level. Observe the recent historical delivery records. If the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or the flow rate in the preset proportion of historical delivery records is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state and is closer to a critical state. The system allows the conveying mode to be actively switched to a dense phase mode and stores the mode switching record in the memory. S510: If two consecutive measurements show that the average pressure of the delivery peak section is at a high level, the system will clear the previous mode switching history data and re-record it. Based on the newly recorded data, if there is no significant drop in flow rate, the system will allow the delivery mode to actively approach the dense phase mode without triggering the mode switch; S511: If pipe blockage occurs twice in succession, the system will clear the previous mode switching history data and re-record it, and switch the conveying mode to the dilute phase mode.

[0009] In some embodiments, the most recent historical delivery records are required to have at least 10 pieces of data; if the flow rate in 40%-60% of the historical delivery records is at a low level and a medium level, it indicates that the current state is a dilute phase state.

[0010] In some embodiments, when pipe blockage occurs during transportation, the pressure tends to rise, and there is no pressure drop trend during the entire process.

[0011] In some embodiments, after the system enters the conveying state, it ensures that the sum of the fluidizing gas and the conveying gas is equal to the preset conveying gas volume. Subsequently, the system converts the calculated conveying gas volume into the corresponding valve opening, while ensuring that the ratio of the conveying gas to the conveying gas volume is not less than 60%, or meets the preset minimum ratio requirement and is not less than 60%.

[0012] In some embodiments, the pressure grading standard plans the pressure fluctuation range [x1, x2] as a medium level, plans the pressure fluctuation range less than x1 as a low level, and plans the pressure fluctuation range greater than x2 as a high level; the flow grading standard plans the flow fluctuation range [y1, y2] as a medium level, plans the flow fluctuation range less than y1 as a low level, and plans the flow fluctuation range greater than y2 as a high level.

[0013] In some embodiments, the flow rate upper limit when the transport mode is dense phase is less than the flow rate upper limit when the transport mode is critical, which is less than the flow rate upper limit when the transport mode is dilute phase; the key parameters initialized after the system receives the startup command include pressure, flow, valve status and transported gas volume; when the system initializes the key parameters, if there is historical transport data, the historical transport data is loaded at the same time, and an initial judgment benchmark is established; the initial judgment benchmark includes the design gas volume, design output and ash-to-gas ratio.

[0014] A pneumatic conveying system applies any of the above-mentioned pneumatic conveying optimization control methods based on conveying state identification.

[0015] Compared with the existing technology, the beneficial effect of the present application is that the pneumatic conveying optimization control method and system based on conveying state identification of the present application intelligently identifies the conveying state (dilute phase, critical phase, dense phase) and optimizes the conveying mode in the pneumatic conveying system by introducing trend analysis of historical conveying data and dynamic monitoring of real-time conveying state, so as to ensure that under complex and changeable operating conditions, the system can automatically adjust the conveying mode, so that different conveying modes can transition smoothly, improve system stability and effectively prevent pipe blockage. At the same time, the technology can also automatically identify and adjust strategies when the risk of pipe blockage increases, and dynamically optimize conveying parameters when the conveying system is unstable, significantly improving the system's adaptability, stability and work efficiency. DETAILED DESCRIPTION

[0016] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0017] The terms "comprises" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, product or apparatus.

[0018] The following is a further description of this application: The present application provides a pneumatic conveying optimization control method based on conveying state identification. The pneumatic conveying states include dilute phase, critical phase and dense phase. Correspondingly, the conveying mode set by the system also includes dilute phase, critical phase and dense phase, which is mainly identified and set based on flow rate, pressure and pipe blockage state. In theory, the corresponding conveying mode is suitable for forming a corresponding pneumatic conveying state in the pipeline. In actual conditions, due to the influence of material properties, environmental conditions and changes in pipeline state, the pneumatic conveying state may deviate from the conveying mode, and the existing technology cannot identify and regulate the conveying mode in a timely and accurate manner, thereby affecting the conveying efficiency and stability.

[0019] If the conveying mode switching strategy is not flexible, it will further lead to unstable system operation. Existing pneumatic conveying systems usually use simple fixed-value control or fixed rules when switching modes, and cannot make intelligent adjustments based on dynamic changes in the conveying state. For example, in the critical conveying mode, the system may not adjust the airflow in time, resulting in material deposition or decreased pneumatic conveying efficiency. It also does not fully consider changes in material properties, which can easily affect conveying stability. Changes in material parameters such as particle size, moisture content, and density will directly affect the selection and switching of conveying modes. Without considering changes in material properties, it is easy to cause improper mode switching, increase the risk of pipe blockage and conveying instability.

[0020] In addition, the traditional mode switching method is prone to sudden changes in pressure and flow rate when converting from dilute phase → critical → dense phase mode, causing excessive impact on pipelines and equipment, shortening the service life of pipelines and valves. At the same time, sudden switching may cause unstable transportation and even create the risk of instantaneous long material blocking the pipe and causing pressure buildup.

[0021] Existing pneumatic conveying systems cannot perceive pipe blockage risks in real time, and their early warning mechanisms are insufficient. Traditional conveying systems mainly rely on preset thresholds to judge pipe blockage risks. However, since the conveying process is affected by many factors (such as pipeline wear, changes in material moisture content, etc.), fixed thresholds are often difficult to adapt to complex working conditions, resulting in the system being unable to issue early warnings before pipe blockage occurs.

[0022] Existing pneumatic conveying systems lack adaptive and self-adjustment capabilities, making them difficult to continuously optimize. The control strategies of traditional pneumatic conveying systems are usually preset fixed parameters and cannot be optimized based on historical conveying conditions. They also fail to fully consider energy consumption optimization and usually operate at a fixed flow rate or pressure. They may still maintain a high energy consumption mode under low load conditions, resulting in energy waste. Even if there are certain abnormalities or inefficiencies in the system, they cannot be adjusted through data, resulting in low long-term system operation efficiency.

[0023] This application addresses the shortcomings of traditional pneumatic conveying systems in terms of state recognition and mode switching, pipe blockage warning, energy consumption optimization and material property adaptability, and proposes an optimization control method and system based on conveying state recognition, which significantly improves the intelligence level and adaptability of the pneumatic conveying system.

[0024] Specifically, this application establishes a multi-dimensional conveying state characteristic model by real-time collection of key parameters such as the average pressure of the peak section, the average flow data of the peak section, and the proportion of fluidizing gas during the conveying process, combined with trend analysis of historical data, so as to accurately identify the three conveying states of dilute phase, critical phase and dense phase, effectively avoiding the misjudgment and switching lag problems caused by the traditional system's reliance on fixed thresholds or manual experience. In terms of mode switching, the system adopts strategy identification to achieve a smooth transition between states.

[0025] When the system detects that the conveying state is tilted towards a certain mode, it can dynamically adjust the gas volume and gas speed according to real-time monitoring data and historical conveying records to achieve a smooth transition of each mode to the optimal operating state; at the same time, when the risk of pipe blockage increases or the material properties change, the system can promptly issue an early warning and adjust the conveying parameters to reduce the incidence of pipe blockage and system energy consumption, ensuring the continuity and stability of the conveying process.

[0026] Through the adaptive optimization mechanism, this application can not only make real-time adjustments to parameters such as particle size, moisture content and density of different materials, but also continuously correct and optimize design parameters based on historical conveying data, thereby achieving optimal energy consumption and enhanced system adaptability in long-term operation.

[0027] In summary, the present invention provides an advanced, intelligent and efficient pneumatic conveying optimization control solution, which not only improves the conveying efficiency and equipment life, but also significantly reduces the risk of pipe blockage and energy consumption, and provides reliable guarantee for the stable operation of the pneumatic conveying system under complex and changeable working conditions. Through innovative methods such as conveying state identification, intelligent mode switching, historical data analysis and real-time data monitoring, it solves many key problems such as misjudgment of conveying mode, large impact of mode switching, insufficient pipe blockage warning, insufficient energy consumption optimization, poor adaptability of material properties, etc. Ultimately, the pneumatic conveying system has higher stability, adaptability and energy efficiency optimization capabilities, ensuring that an efficient, stable and energy-saving conveying process can be achieved under different operating conditions.

[0028] In order to solve the above-mentioned defects of the traditional pneumatic conveying system, the optimization control method designed in this application specifically includes the following steps.

[0029] S100, define calculation indicators. During the system design phase, pressure classification standards and flow classification standards are established through calculation and named as system design pressure parameters. The pressure classification standards and flow classification standards are planned into three levels: low, medium, and high according to the fluctuation range of pressure and flow, respectively, to assist the system in identifying the delivery mode.

[0030] In some embodiments, the pressure grading standard plans the pressure fluctuation range [x1, x2] as a medium level, plans the pressure fluctuation range less than x1 as a low level, and plans the pressure fluctuation range greater than x2 as a high level. In this application, x1 and x2 are percentage values. For example, the fluctuation range of 90% to 115% is planned as a medium level, the fluctuation range less than 90% is planned as a low level, and the fluctuation range greater than 115% is planned as a high level.

[0031] In some embodiments, the traffic grading standard plans the traffic fluctuation range [y1, y2] as a medium level, plans the traffic fluctuation range less than y1 as a low level, and plans the traffic fluctuation range greater than y2 as a high level. In this application, y1 and y2 are percentage values. For example, the fluctuation range of 90% to 115% is planned as a medium level, the fluctuation range less than 90% is planned as a low level, and the fluctuation range greater than 115% is planned as a high level.

[0032] It is worth noting that the division intervals of the above-mentioned level planning are set based on engineering experience and the perception of the degree of fluctuation in actual applications. They can be adjusted according to specific application scenarios, equipment characteristics or control accuracy requirements. For example, in some systems that are more sensitive to fluctuations, a narrower range (such as 95%~105%) may be used, while in systems with higher fluctuation tolerance, it may be appropriately relaxed.

[0033] S200: After receiving the start command, the control unit of the system enters the preparation mode, activates the sensor module, initializes key parameters, and establishes an initial judgment benchmark. The system enters the waiting state for delivery and responds to material delivery needs at any time.

[0034] The key parameters initialized after the system receives the start-up command include pressure, flow, valve status and gas delivery volume.

[0035] When the system initializes key parameters, if there is historical transportation data, the historical transportation data will be loaded at the same time and an initial judgment benchmark will be established.

[0036] In this application, the initial judgment criteria include the designed gas volume, designed output and ash-to-gas ratio. Each system will have a designed gas volume, designed output and ash-to-gas ratio during the design phase. The initial transportation mode can be confirmed through the above design parameters.

[0037] S300, the system enters the conveying state, and the control unit determines the current conveying mode (dilute phase, critical phase or dense phase) based on the initial judgment benchmark, and stores the real-time collected pressure and flow data into the memory for subsequent trend analysis and mode optimization adjustment.

[0038] In some embodiments, after the system enters the conveying state, it ensures that the sum of the fluidizing gas and the conveying gas is equal to the preset conveying gas volume. Subsequently, the system converts the calculated conveying gas volume into the corresponding valve opening, while ensuring that the ratio of the conveying gas to the conveying gas volume is not less than 60%, or meets the preset minimum ratio requirement and is not less than 60%, thereby ensuring the stability and efficiency of the conveying process. Since the sum of the fluidizing gas and the conveying gas is equal to the preset conveying gas volume, when the conveying gas volume value is very large, directly using 60% will make the conveying gas appear very small. At this time, it would be more appropriate to use the minimum ratio. Generally, the data of 60% can be applied to designs.

[0039] S400, after each delivery is completed, the pressure and flow rate of the delivery peak section are obtained according to the collected pressure and flow rate data, and converted into corresponding average values ​​and stored in the memory.

[0040] Among them, the definition of the delivery peak segment is: within a complete delivery cycle, the change process of the delivery pressure can be roughly divided into three stages: first, the pressure gradually rises from 0; when the pressure approaches the maximum value, it will remain relatively stable in the high-pressure area and last for a period of time; finally, the pressure gradually decreases until it returns to 0, completing the entire delivery process; so the delivery peak segment can be taken from the time when the high-pressure area remains relatively stable and lasts.

[0041] S500, according to the current conveying mode, the control unit executes the control strategy, which is based on the level of the average pressure of one or two consecutive conveying peak segments, combined with the level change trend or level distribution ratio of the average flow rate of the conveying peak segment in the recent historical conveying records (each complete conveying cycle is regarded as a statistic), to identify and analyze the current pneumatic conveying state, and enable the control unit to switch the conveying mode, adjust the conveying mode or maintain the current conveying mode.

[0042] In some embodiments, the most recent historical delivery records require at least 10 data items. A sample size that is too small will reduce the representativeness of the data, and the data will fluctuate greatly, making it difficult to reflect the actual operating trend of the system and prone to misjudgment. Considering the periodic and stage characteristics of the delivery task, 10 or more data items are required to cover the fluctuation characteristics of a complete working cycle.

[0043] If the flow rate in 40%-60% of the historical transmission records is at low and medium levels, it indicates that the current state is dilute phase.

[0044] In some embodiments, if the flow rate in 45%-55% of the historical delivery records is at low and medium levels, it indicates that the current state is in a dilute phase state. 50% is preferred. While reflecting the recent operating trends, it can filter out old data that is too early and has no reference value. 50% is an empirical value that strikes a balance between stability and real-time performance.

[0045] In the present application, the corresponding relationship between the flow rate upper limit in each conveying mode is: the flow rate upper limit when the conveying mode is dense phase < the flow rate upper limit when the conveying mode is critical < the flow rate upper limit when the conveying mode is dilute phase.

[0046] Wherein, when the current delivery mode is dilute phase, step S500 includes the following steps.

[0047] S501, the measurement data shows that the average pressure of the peak delivery section is at a low level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low (specifically, it can be a trend of gradually decreasing from high to medium and then to low), or a preset proportion (nearly 50%) of the historical delivery flow rate is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to be switched to a dense phase mode (switchable or not), and responds to high-concentration conveying needs by reducing the gas velocity and appropriately increasing the material supply. At the same time, pipe blockage prevention and control measures are strengthened, and the mode switching record is stored in the memory.

[0048] S502: The measurement data shows that the average pressure of the peak delivery section is at a medium level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low (specifically, it can be a trend of gradually decreasing from high to medium and then to low), or the flow rate in the preset proportion (nearly 50%) of the historical delivery records is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to be switched to a critical mode (which can be switched or not), and responds to high-concentration conveying needs by reducing the gas velocity and appropriately increasing the material supply. At the same time, it attempts to approach the dense phase mode, and stores the mode switching record in the memory.

[0049] S503, if two consecutive measurement data show that the average pressure of the delivery peak section is at a high level (regardless of whether the flow rate remains high or decreases slightly), the system will clear the previous mode switching history data and re-record it, indicating that the current pneumatic conveying state is in the dilute phase state. At this time, it means that the pressure in the dilute phase mode is generally high, and the pressure in other modes is even higher. Therefore, the system should maintain the current mode and not switch. In addition, if the measurement data limits the average pressure of the delivery peak section to a high level, it will be treated as an accidental event and no operation will be performed.

[0050] It is worth noting that if it is the first delivery, or the first delivery after clearing the switching history record, for the judgment condition that the flow rate in the preset proportion of historical delivery is at a low level and a medium level, the number of delivery records at this time does not meet the judgment logic and the operation is not performed. The system should maintain the current mode and continue to deliver until the delivery record meets the judgment logic. The same applies to the execution control strategy of other delivery modes.

[0051] When the current delivery mode is dense phase, step S500 includes the following steps.

[0052] S504, the measurement data shows that the average pressure of the peak delivery section is at a low level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low (specifically, it can be a trend of gradually decreasing from high to medium and then to low), or a preset proportion (nearly 50%) of the historical delivery flow rate is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state. At this time, the system believes that such a low pressure and flow distribution should not appear in a dense phase state. Therefore, the delivery mode is not switched and the system maintains the current state.

[0053] S505, the measurement data shows that the average pressure of the peak delivery section is at a medium level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low (specifically, it can be a trend of gradually decreasing from high to medium and then to low), or the flow rate in the preset proportion (nearly 50%) of the historical delivery records is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state and is closer to a critical state. At this time, the system believes that the state is still within the controllable range, does not trigger the mode switch, and the system maintains the current state.

[0054] S506: If two consecutive measurement data show that the average pressure of the delivery peak section is at a high level (regardless of whether the flow rate remains high or decreases slightly), the system will clear the previous mode switching history data and re-record it. At this time, it indicates that the pressure in the current dense phase mode is generally high. The system determines that the overload risk is increasing and allows the delivery mode to be actively switched to the critical mode to reduce the pressure risk of the delivery system and improve the delivery status. In addition, if the measurement data of one time limits the average pressure of the delivery peak section to a high level, it will be treated as an accidental event and no operation will be performed.

[0055] S507, if pipe blockage occurs twice in succession (regardless of whether the flow rate remains high or decreases slightly, when pipe blockage occurs during the transportation process, the pressure curve usually shows a continuous upward trend: the pressure gradually increases from zero in the initial stage, and there may be a short stable period, but then it will continue to rise; there will be no pressure drop trend during the entire process, and the system can make a pipe blockage judgment based on this logic), the system will clear the previous mode switching history data and re-record it. At this time, it indicates that the pressure is abnormal in the dense phase mode and the risk of pipe blockage is extremely high. The system judges that the overload is too large and allows the transportation mode to be actively switched to the dilute phase mode to quickly stabilize the transportation process. In addition, if pipe blockage occurs only once, it will be treated as an accidental event and no operation will be performed.

[0056] When the current delivery mode is critical, step S500 includes the following steps.

[0057] S508, the measurement data shows that the average pressure of the peak delivery section is at a low level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low (specifically, it can be a trend of gradually decreasing from high to medium and then to low), or the flow rate in the preset proportion (nearly 50%) of the historical delivery records is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to actively switch to a dense phase mode by reducing the gas velocity and appropriately increasing the material supply to cope with the high-concentration conveying demand. At the same time, it strengthens the pipe blockage prevention and control measures, and stores the mode switching record in the memory.

[0058] S509, the measurement data shows that the average pressure of the peak delivery section is at a medium level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low (specifically, it can be a trend of gradually decreasing from high to medium and then to low), or the flow rate in the preset proportion (nearly 50%) of the historical delivery records is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state and is closer to a critical state. The system allows the conveying mode to actively switch to a dense phase mode, by reducing the gas velocity and appropriately increasing the material supply to cope with the high-concentration conveying demand, while strengthening the pipe blockage prevention and control measures, and storing the mode switching record in the memory.

[0059] S510: If two consecutive measurement data show that the average pressure of the peak delivery section is at a high level (regardless of whether the flow rate remains high or decreases slightly), the system will clear the previous mode switching history data and re-record it. This indicates that the current delivery state is gradually tilting towards the dense phase, and the risk of pressure overload is increasing. Based on the newly recorded data, if the flow rate does not decrease significantly, the system allows the delivery mode to actively approach the dense phase mode without triggering the mode switch, and maintains the current state unchanged.

[0060] S511: If pipe blockage occurs twice in succession (regardless of whether the flow rate remains high or decreases slightly), the system will clear the previous mode switching history data and re-record it. At this time, it indicates that the pressure in the dense phase mode is abnormal and the risk of pipe blockage is extremely high. The system determines that the overload is too large and switches the conveying mode to the dilute phase mode to quickly stabilize the conveying process.

[0061] The present application also provides a pneumatic conveying system, which applies the pneumatic conveying optimization control method based on conveying state identification of any of the above embodiments.

[0062] The control unit collects conveying data in real time through pressure sensors and flow sensors, and combines historical conveying trend analysis and dynamic monitoring to realize intelligent identification and optimization of conveying modes. When the material properties change, the system can adaptively adjust and accurately control the progressive conversion of dilute phase → critical → dense phase, dense phase → critical → dilute phase, dilute phase → dense phase, and dense phase → dilute phase. At the same time, it can perceive the risk of pipe blockage in real time to ensure the stability and efficiency of the conveying process, optimize energy consumption, and enhance the self-adjustment ability of the system, so that the conveying mode is always in the best operating state.

[0063] This optimized configuration enables the present application to accurately and efficiently implement a pneumatic conveying optimization control method and system based on conveying state identification, providing a more stable and efficient intelligent control solution for the conveying process. By integrating the dynamic change rules of pressure, flow and system design parameters, the present application ensures that the pneumatic conveying system can autonomously identify and optimize the conveying mode under different operating conditions, thereby improving the system's adaptability and enhancing the stability and efficiency of the conveying process.

[0064] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments. The above embodiments and the specification only describe the principles of the present application. Various changes and improvements may be made to the present application without departing from the spirit and scope of the present application. These changes and improvements fall within the scope of the present application to be protected, and the scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A pneumatic conveying optimization control method based on conveying state identification, wherein the pneumatic conveying states include dilute phase, critical phase and dense phase, characterized in that: Including steps: S100, define calculation indicators, establish pressure classification standards and flow classification standards during the system design phase, and plan the pressure classification standards and flow classification standards into three levels: low, medium, and high according to the fluctuation range of pressure and flow respectively; S200, after receiving the start command, the control unit of the system activates the sensor module, initializes key parameters, establishes an initial judgment benchmark, and enters a waiting state for delivery; S300, the system enters the delivery state, the control unit determines the current delivery mode based on the initial judgment standard, and stores the real-time collected pressure and flow data into the memory; S400, after each delivery is completed, the pressure and flow rate of the delivery peak section are obtained based on the collected pressure and flow rate data, and converted into corresponding average values ​​and stored in the memory; S500, according to the current conveying mode, the control unit executes the control strategy, the control strategy is based on the level of the average pressure of one or two consecutive conveying peak segments, combined with the level change trend or level distribution ratio of the average flow rate of the conveying peak segment in the recent historical conveying records, to identify and analyze the current pneumatic conveying state, and enable the control unit to switch the conveying mode, adjust the conveying mode or maintain the current conveying mode.

2. A pneumatic conveying optimization control method based on conveying state identification according to claim 1, characterized in that: When the current delivery mode is dilute phase, step S500 includes: S501: The measured data shows that the average pressure of the peak delivery section is at a low level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low, or the preset proportion of historical delivery flow rates are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to be switched to a dense phase mode and stores the mode switching record in the memory. S502: The measured data shows that the average pressure of the delivery peak section is at a medium level. Observe the recent historical delivery records. If the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or if the flow rates in a preset proportion of historical delivery records are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to switch to a critical mode while attempting to move closer to a dense phase mode, and stores the mode switching record in the memory. S503, if two consecutive measurement data show that the average pressure of the delivery peak section is at a high level, the system will clear the previous mode switching history data and re-record it, indicating that the current pneumatic conveying state is in a dilute phase state, and the system maintains the current mode without switching.

3. The pneumatic conveying optimization control method based on conveying state identification according to claim 1, characterized in that: When the current delivery mode is dense phase, step S500 includes: S504: The measured data shows that the average pressure of the peak delivery section is at a low level. Observe the recent historical delivery records. If the average flow rate of the peak delivery section shows a trend of gradually decreasing from high, medium, and low, or the preset proportion of historical delivery flow rates are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state, and the system maintains the current state. S505: The measured data shows that the average pressure of the delivery peak section is at a medium level. Observing the recent historical delivery records, if the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or if the flow rates in a preset proportion of historical delivery records are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state and is closer to a critical state, and the system maintains the current state. S506, if two consecutive measurement data show that the average pressure of the delivery peak section is at a high level, the system will clear the previous mode switching history data and re-record it, and allow the delivery mode to be actively switched to the critical mode; S507: If pipe blockage occurs twice in succession, the system will clear the previous mode switching history data and re-record it, and allow the conveying mode to be actively switched to the dilute phase mode.

4. The pneumatic conveying optimization control method based on conveying state identification according to claim 1, characterized in that: When the current delivery mode is critical, step S500 includes: S508: The measured data shows that the average pressure of the delivery peak section is at a low level. Observe the recent historical delivery records. If the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or the flow rates in a preset proportion of historical delivery records are at low and medium levels, it indicates that the current pneumatic conveying state is in a dilute phase state. The system allows the conveying mode to be actively switched to a dense phase mode and stores the mode switching record in the memory. S509: The measured data shows that the average pressure of the delivery peak section is at a medium level. Observe the recent historical delivery records. If the average flow rate of the delivery peak section shows a trend of gradually decreasing from high, medium, and low, or the flow rate in the preset proportion of historical delivery records is at a low level and a medium level, it indicates that the current pneumatic conveying state is in a dilute phase state and is closer to a critical state. The system allows the conveying mode to be actively switched to a dense phase mode and stores the mode switching record in the memory. S510: If two consecutive measurements show that the average pressure of the delivery peak section is at a high level, the system will clear the previous mode switching history data and re-record it. Based on the newly recorded data, if there is no significant drop in flow rate, the system will allow the delivery mode to actively approach the dense phase mode without triggering the mode switch; S511: If pipe blockage occurs twice in succession, the system will clear the previous mode switching history data and re-record it, and switch the conveying mode to the dilute phase mode.

5. The pneumatic conveying optimization control method based on conveying state identification according to any one of claims 2 to 4, characterized in that: The most recent historical delivery records require at least 10 data items; if the flow rate in 40%-60% of the historical delivery records is at low and medium levels, it indicates that the current state is dilute phase.

6. A pneumatic conveying optimization control method based on conveying state identification according to claim 3 or 4, characterized in that: When pipe blockage occurs during transportation, the pressure will tend to rise, and there will be no pressure drop during the entire process.

7. The pneumatic conveying optimization control method based on conveying state identification according to claim 1, characterized in that: After the system enters the conveying state, it ensures that the sum of the fluidizing gas and the conveying gas is equal to the preset conveying gas volume. Then, the system converts the calculated conveying gas volume into the corresponding valve opening, while ensuring that the ratio of conveying gas to the conveying gas volume is not less than 60%, or meets the preset minimum ratio requirement and is not less than 60%.

8. The pneumatic conveying optimization control method based on conveying state identification according to claim 1, characterized in that: The pressure classification standard plans the pressure fluctuation range [x1, x2] as the medium level, the pressure fluctuation range less than x1 as the low level, and the pressure fluctuation range greater than x2 as the high level; the flow classification standard plans the flow fluctuation range [y1, y2] as the medium level, the flow fluctuation range less than y1 as the low level, and the flow fluctuation range greater than y2 as the high level.

9. The pneumatic conveying optimization control method based on conveying state identification according to claim 1, characterized in that: The upper limit of flow rate when the conveying mode is dense phase is less than the upper limit of flow rate when the conveying mode is critical, which is less than the upper limit of flow rate when the conveying mode is dilute phase; the key parameters initialized after the system receives the start-up command include pressure, flow rate, valve status and conveying gas volume; when the system initializes key parameters, if there is historical conveying data, the historical conveying data will be loaded at the same time, and an initial judgment benchmark will be established; the initial judgment benchmark includes design gas volume, design output and ash-to-gas ratio.

10. A pneumatic conveying system, characterized in that: Apply the pneumatic conveying optimization control method based on conveying state identification as described in any one of claims 1 to 9.