High-viscosity chemical material pipeline efficient conveying and anti-blocking method

Abstract

The present application relates to a kind of high viscosity chemical material pipeline efficient conveying and anti-blocking method.The method real-time acquisition material temperature, apparent viscosity, conveying flow, pipe diameter, pipe wall shear stress and pipeline pressure difference in conveying process, according to conveying flow and pipe diameter, calculate the nominal shear rate of near-wall region, and back-calculate the thickness change rate of virtual adhesion boundary layer of pipe wall.When the change rate is positive, and exceeds preset threshold, determine that the adhesion layer of pipe wall is in growth state, trigger ultrasonic pulse generator, and link adjustment conveying pump outlet pressure and / or conveying flow, so that the change rate is reduced to zero or negative value.The present application can actively identify and inhibit the growth of adhesion layer of pipe wall before blockage formation, improve the stability and anti-blocking ability of continuous conveying of high viscosity material.

Description

Technical Field

[0001] This invention relates to the field of chemical material conveying technology, and in particular to a pipeline conveying control method for high-viscosity chemical materials. Specifically, it relates to a highly efficient conveying and anti-clogging method based on closed-loop regulation of pipe wall shear state and adhesion layer change trend. Background Technology

[0002] In industries such as petrochemicals, fine chemicals, polymer materials, and food chemicals, it is often necessary to transport high-viscosity materials through pipelines, such as polymer melts, epoxy resins, adhesives, high-concentration slurries, and asphalt-based materials. These materials typically have high apparent viscosity, poor flowability, are prone to shear thinning, and exhibit strong adhesion to pipe walls. During pipeline transport, due to the radial velocity gradient distribution of the fluid, the flow velocity near the pipe wall is lower, easily forming a low-shear zone or even a stagnant zone. This leads to material adhesion and accumulation near the pipe wall, gradually forming an adhesive layer or semi-solidified layer.

[0003] As the conveying process continues, the adhesion layer gradually thickens, reducing the effective flow cross-sectional area of ​​the pipeline. This leads to increased flow resistance, higher pipeline pressure differential, and increased system energy consumption. In extreme cases, the adhesion layer may further harden or locally solidify, ultimately causing pipeline blockage and severely impacting production continuity and equipment operational safety. Therefore, effectively suppressing the formation and growth of the adhesion layer on the pipe wall while ensuring conveying efficiency is one of the urgent technical problems to be solved in the field of high-viscosity material pipeline transportation.

[0004] To address the aforementioned problems, existing technologies typically employ methods such as increasing the pressure of the delivery pump, raising the material temperature, or periodically cleaning the pipeline. For example, increasing the delivery pressure increases the overall shear rate of the fluid, thereby reducing adhesion tendency; or heating the pipeline reduces material viscosity and improves flowability. However, these methods are mostly single-parameter adjustment means and have significant limitations. On the one hand, simply increasing the pressure can easily lead to excessive local shear, causing increased energy consumption and potentially causing degradation of heat-sensitive materials; on the other hand, while relying solely on heating can reduce viscosity, it is difficult to effectively eliminate adhesion in the low-shear zone of the pipe wall, and excessively high temperatures may also affect material properties.

[0005] In addition, existing technologies also employ methods such as periodic backflushing, solvent cleaning, or mechanical cleaning to remove deposits from the pipe walls. These methods typically require shutdown operations, making it difficult to meet the requirements of continuous production, and increasing operating costs and complexity. Meanwhile, some technologies introduce vibration or ultrasonic methods to improve flow conditions, but these are mostly fixed-parameter methods, lacking the ability to dynamically adjust according to the real-time state of the material, and thus failing to adapt to changes in the adhesion layer under different operating conditions.

[0006] Furthermore, existing technologies, such as CN113533135B, employ closed-loop control of transport flow rate based on non-Newtonian fluid rheological properties, shear rate, and pipe wall shear stress. These solutions primarily focus on stabilizing the transport flow rate based on fluid rheological properties to improve flow stability during transport. However, these solutions do not quantitatively characterize the formation and growth process of the adhesion layer on the pipe wall for high-viscosity materials, nor do they use the change rate of the virtual adhesion boundary layer thickness as a criterion for judging the adhesion layer growth trend. Furthermore, they do not link the ultrasonic pulse action with the pump outlet pressure and / or transport flow rate for closed-loop regulation. Therefore, these solutions still lack the ability to effectively identify and actively suppress the adhesion layer on the pipe wall.

[0007] In summary, existing technologies generally lack quantitative characterization methods for the formation and growth process of the adhesion layer on the pipe wall, cannot reflect the development trend of the adhesion layer in real time, and lack a closed-loop control mechanism for multi-parameter linkage regulation based on this trend. Therefore, it is difficult to effectively suppress the adhesion layer under complex transportation conditions.

[0008] Therefore, it is necessary to provide a method for pipeline transportation and anti-clogging of high-viscosity chemical materials that can combine material rheological properties and pipeline operating parameters to quantitatively characterize the changes in the pipe wall adhesion layer, and based on the characterization results, realize the coordinated adjustment of transportation parameters and external disturbance methods, so as to improve the stability, continuity and safety of the transportation process. Summary of the Invention

[0009] In view of this, the purpose of this invention is to provide a method for efficient pipeline transportation and anti-clogging of high-viscosity chemical materials, so as to solve the problems of easy formation of pipe wall adhesion layer, increased pressure difference, increased energy consumption and high risk of blockage during the existing pipeline transportation of high-viscosity materials, and to achieve quantitative characterization and active inhibition of the growth trend of pipe wall adhesion layer, rather than being limited to stable control of the transportation flow rate.

[0010] To achieve the above objectives, the present invention provides the following technical solution: In one possible implementation, a method for efficient pipeline transportation and anti-clogging of high-viscosity chemical materials is characterized by comprising the following steps: During the conveying process, the material temperature T, conveying flow rate Q, apparent viscosity μ(T), pipe diameter D, pipe wall shear stress τw_real, and pressure difference ΔP between the pipe inlet and outlet are collected in real time. The nominal shear rate γ in the near-wall region is calculated based on the flow rate Q and the pipe diameter D. The rate of change of the virtual adhesion boundary layer thickness in the pipe wall is calculated based on the following relationship: ; in, δ is the adhesion characteristic correction factor, α is the equivalent impedance coefficient for adhesion layer growth; where δ is the thickness of the virtual adhesion boundary layer on the pipe wall.

[0011] When the When the value is positive and exceeds a preset threshold, it is determined that the pipe wall adhesion layer is in a growth state; when it is determined that the pipe wall adhesion layer is in a growth state, an ultrasonic pulse generator installed on the delivery pipeline is triggered; at the same time, the outlet pressure of the delivery pump and / or the delivery flow rate are adjusted to make the change rate of the virtual adhesion boundary layer thickness of the pipe wall... The value is reduced to zero or negative, thereby inhibiting the growth of the adhesion layer on the pipe wall and achieving continuous anti-clogging transportation.

[0012] In one possible implementation, the pulse frequency f of the ultrasonic pulse generator satisfies the following relationship: ; in, This is a dimensionless frequency correction coefficient.

[0013] In one possible implementation, the preset threshold is 0.005 mm / h to 0.02 mm / h.

[0014] In one possible implementation, when determining that the pipe wall adhesion layer is in a growth state, the judgment is also made in conjunction with the changing trend of the pipe pressure difference ΔP. When the value is positive and the pipeline pressure difference ΔP shows an upward trend, it is determined that the adhesion layer is in a state of continuous growth.

[0015] In one possible implementation, the adjustment of the delivery pump outlet pressure and / or delivery flow rate employs a closed-loop control method, wherein the closed-loop control includes: Based on the change rate of the virtual adhesion boundary layer thickness of the pipe wall Based on the calculation results, perform at least one of the following adjustment operations: a) Adjust the intensity of the ultrasonic pulse; b) Adjust the delivery flow rate; c) Adjust the delivery pressure; After the adjustment is completed, the parameters are re-acquired and dδ / dt is calculated. The adjustment is continued or the current state is maintained based on the recalculation results.

[0016] In one possible implementation, the ultrasonic pulse intensity increases in increments of 5% to 10%, and the delivery flow rate increases in increments of 3% to 5%.

[0017] In one possible implementation, adjustment is stopped and the current delivery state is maintained when the following condition is met: τw_real ≥ 0.9~0.95 × τw_target, and ≤ 0; where τw_target is the target pipe wall shear stress.

[0018] In one possible implementation, the ultrasonic pulse generators are spaced apart along the axial direction of the delivery pipe, with the distance between two adjacent ultrasonic pulse generators being 5 to 10 times the inner diameter of the pipe.

[0019] In one possible implementation, the material temperature T is controlled within the viscosity-temperature operating range, which satisfies the following conditions: the material temperature is below the thermal degradation temperature; the apparent viscosity decreases with increasing shear rate; the shear rate in the near-wall region is not lower than a preset critical shear rate; and the change rate of the virtual adhesion boundary layer thickness on the pipe wall is [not specified]. It can be controlled to be zero or negative.

[0020] In one possible implementation, the adhesion property correction coefficient The value range is 0.85 to 1.20, and the equivalent impedance coefficient of the adhesion layer growth is... The calibration was determined based on material rheology tests and pipeline transportation tests.

[0021] Based on the above technical solution, the present invention provides a method for efficient pipeline transportation and anti-clogging of high-viscosity chemical materials. This method involves real-time acquisition of key operating parameters during transportation, such as material temperature, apparent viscosity, flow rate, pipe diameter, pipe wall shear stress, and pipeline pressure difference. The method calculates the near-wall shear rate and further calculates the change rate of the virtual adhesion boundary layer thickness on the pipe wall, thereby achieving a quantitative characterization of the adhesion layer growth trend. Furthermore, when the adhesion layer is determined to be in a growth state, an ultrasonic pulse generator is triggered to apply transient shear disturbance to the material near the pipe wall. Simultaneously, the outlet pressure of the delivery pump and / or the flow rate are adjusted to optimize the pipe wall shear conditions, thereby gradually reducing the adhesion boundary layer thickness change rate to zero or a negative value.

[0022] Through the aforementioned closed-loop control mechanism based on the "adhesion layer change rate," proactive intervention can be implemented before the adhesion layer develops into severe accumulation or blockage, achieving a shift from "passive removal" to "active inhibition." Compared to traditional methods that rely solely on increasing pressure or temperature, this invention can effectively weaken the adhesion layer growth trend in the low-shear zone of the pipe wall, reducing the risk of material degradation, while avoiding excessively high local shear and heat accumulation.

[0023] Furthermore, by combining ultrasonic pulse action with the adjustment of delivery parameters, a dynamic disturbance environment is created near the pipe wall, which helps to disrupt the adhesion structure that has not yet stabilized, thereby improving the peeling efficiency of the adhesion layer. Simultaneously, by setting threshold judgments and stopping conditions during the adjustment process, the system maintains optimal operating conditions after reaching a stable delivery state, avoiding increased energy consumption due to over-adjustment.

[0024] Therefore, this invention can achieve stable control of the pipeline transportation process of high-viscosity materials under complex working conditions and different material conditions, increase continuous operation time, reduce the risk of blockage, reduce the need for downtime cleaning, and improve overall transportation efficiency and process safety.

[0025] The technical advantage of this invention lies in its proposed active anti-clogging closed-loop control method to address the problem of pipe wall adhesion layer growth during the pipeline transportation of high-viscosity chemical materials. Specifically, this is manifested in the following three aspects: 1. Active suppression before blockage occurs: This invention uses real-time calculation of the change rate of the virtual adhesion boundary layer thickness on the pipe wall (… This allows for proactive intervention in blockages, rather than reactive treatment of pipe blockages, by identifying growth trends and initiating control measures before a significant buildup of the adhesion layer forms.

[0026] 2. Using the growth rate of the adhesion layer as the control target: The control system uses the change rate of the thickness of the adhesion layer on the pipe wall as the core adjustment index. Through closed-loop feedback, it adjusts the delivery parameters in real time to keep the growth rate of the adhesion layer on the pipe wall at zero or negative, so as to suppress the growth of the adhesion layer earlier and more accurately, rather than relying solely on traditional pressure difference or flow rate changes as the control target.

[0027] 3. Synergistic effect of ultrasound and pump parameters: Upon detecting adhesion layer growth, the system first triggers an ultrasonic pulse to apply transient shear disturbance to the material near the pipe wall; simultaneously, it adjusts the outlet pressure and flow rate of the delivery pump to optimize near-wall shear conditions. Through the synergistic closed-loop adjustment of ultrasonic disturbance and delivery parameters, this invention significantly improves the adhesion layer suppression effect, and compared to using ultrasound alone or adjusting the pump alone, it can maintain delivery continuity and anti-clogging performance more efficiently.

[0028] In summary, this invention achieves efficient anti-clogging of high-viscosity material pipeline transportation by actively identifying the adhesion layer change rate as the core indicator and using multi-parameter coordinated control, providing a reliable technical guarantee for continuous and stable transportation. Attached Figure Description

[0029] To more clearly illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings. The drawings are merely illustrative representations of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0030] Figure 1 This is a schematic diagram of the high-efficiency pipeline transportation and anti-clogging system for high-viscosity chemical materials described in this invention. Figure 2 This is a schematic diagram of the control process for the efficient pipeline transportation and anti-clogging method of high-viscosity chemical materials described in this invention.

[0031] The components or parameters corresponding to each mark in the attached diagram are explained below: 1—Transportation pipe, 2—Heating jacket, 3—Temperature sensor, 4—Flow meter, 5—Pressure sensor, 6—Pipe wall shear stress sensor, 7—Ultrasonic pulse generator, 8—Transportation pump, 9—Control system; T—Material temperature, Q—Transportation flow rate, μ(T)—Apparent viscosity, D—Pipe diameter, τw_real—Pipe wall shear stress, ΔP—Pipe pressure difference, γ—Nominal shear rate in the near-wall region —Thickness of the virtual adhesion boundary layer on the pipe wall — Rate of change of virtual adhesion boundary layer thickness on pipe wall, k— Adhesion characteristic correction coefficient —Equivalent impedance coefficient for adhesion layer growth, β—Frequency correction coefficient, f—Ultrasonic pulse frequency. Detailed Implementation

[0032] To facilitate understanding of the technical solution of the present invention, specific embodiments of the present invention will be described below in conjunction with the accompanying drawings. It should be understood that the following embodiments are further explanations of the system structure, control flow, key parameters, and implementation effects under the overall technical concept of the present invention. Their purpose is to help those skilled in the art to more clearly understand and implement the present invention, and do not constitute a limitation on the scope of protection of the present invention.

[0033] The core idea of ​​this invention is to: collect parameters such as temperature, viscosity, flow rate, pipe wall shear stress and pressure difference during the high-viscosity material transportation process in real time, calculate the nominal shear rate in the near-wall region, and further calculate the change rate of the virtual adhesion boundary layer thickness of the pipe wall; when it is determined that the adhesion layer on the pipe wall has a growth trend, the control system triggers the ultrasonic pulse generator and adjusts the transportation flow rate and / or transportation pressure in conjunction to reduce the change rate of the adhesion layer to zero or a negative value, thereby achieving active suppression of the risk of pipeline blockage.

[0034] In the following implementation, firstly, combined with Figure 1 The composition of the system of the present invention and the connection relationship between the components are explained; secondly, in conjunction with... Figure 2 The closed-loop control process of the method of the present invention is described; then the key parameters, implementation points and specific embodiments are explained.

[0035] System overall structure (combined) Figure 1 ) like Figure 1 As shown, this invention provides a high-efficiency pipeline transportation and anti-clogging system for high-viscosity chemical materials, comprising a transportation pipeline 1, a heating jacket 2, a temperature sensor 3, a flow meter 4, a pressure sensor 5, a pipe wall shear stress sensor 6, an ultrasonic pulse generator 7, a transportation pump 8, and a control system 9. These components cooperate to form a closed-loop system for continuous transportation and anti-clogging control of high-viscosity materials.

[0036] Specifically, the conveying pipeline 1 is used as a flow channel to carry high-viscosity materials. It can be a straight pipe or a pipeline structure formed by connecting multiple pipe sections. It is preferably made of stainless steel or corrosion-resistant alloy materials to adapt to the conveying environment of high-temperature, high-viscosity, and corrosive chemical materials. The inner diameter of the conveying pipeline 1 is selected according to the actual working conditions, for example, DN25 to DN100 is applicable.

[0037] A heating jacket 2 is installed on the outside of the conveying pipeline 1 to regulate the temperature of the material inside the pipeline. The heating jacket 2 can be heated by steam, thermal oil, or electricity to maintain the material within a preset viscosity-temperature range. By stably controlling the temperature, the viscosity of the material can be reduced and its flowability improved, while preventing thermal degradation caused by excessively high temperatures.

[0038] Temperature sensor 3 is installed at an appropriate location in the conveying pipeline 1 to detect the temperature T of the material inside the pipeline in real time. Preferably, multiple temperature sensors 3 can be arranged at the pipeline inlet, middle section, and outlet to improve the accuracy and representativeness of temperature acquisition.

[0039] Flow meter 4 is installed on the conveying pipeline 1 to measure the material flow rate Q in real time. The flow meter 4 can be a mass flow meter or a volumetric flow meter suitable for high-viscosity fluids to ensure measurement accuracy.

[0040] Pressure sensor 5 is installed at the inlet and outlet of the conveying pipeline 1 to measure the inlet and outlet pressures respectively, thereby calculating the pipeline pressure difference ΔP. This pressure difference reflects the change in flow resistance within the pipeline and is an important auxiliary parameter for judging the growth of the adhesion layer.

[0041] The pipe wall shear stress sensor 6 is installed on or near the inner wall of the conveying pipe 1 to measure the shear stress τw_real at the pipe wall in real time. This parameter directly reflects the flow state of the fluid near the pipe wall and is one of the key inputs for the back calculation of the adhesion layer change rate in this invention.

[0042] Ultrasonic pulse generators 7 are arranged at intervals along the axial direction of the conveying pipe 1, preferably with the spacing between two adjacent ultrasonic pulse generators being 5 to 10 times the inner diameter of the pipe. The ultrasonic pulse generators 7 are used to generate periodic or pulsed vibration disturbances near the pipe wall, thereby peeling off the material layer that has not yet been stably attached and inhibiting the continuous growth of the adhesion layer.

[0043] The conveying pump 8 is located at the inlet end of the conveying pipeline 1 and is used to provide conveying power for materials. The conveying pump 8 can be a screw pump, gear pump, or plunger pump, which is suitable for high-viscosity fluids, and its output pressure and flow rate can be adjusted by the control system.

[0044] The control system 9 is electrically connected to the temperature sensor 3, flow meter 4, pressure sensor 5, pipe wall shear stress sensor 6, ultrasonic pulse generator 7, and delivery pump 8, respectively, for data acquisition, parameter calculation, and control command output. The control system 9 has a built-in function for calculating the near-wall shear rate γ and the rate of change of the virtual adhesion boundary layer thickness on the pipe wall. The algorithm module performs linkage control on the ultrasonic pulse generator 7 and the delivery pump 8 based on the calculation results, thereby forming a closed-loop regulation mechanism.

[0045] Through the above structural design, the system of the present invention can not only acquire key parameters reflecting the flow state and adhesion trend in real time, but also dynamically adjust the conveying process based on the parameters, thereby intervening in the early stage of adhesion layer formation and improving the stability and anti-clogging ability of the high viscosity material conveying process.

[0046] II. Control Methods and Procedures (in conjunction with...) Figure 2 ) like Figure 2 As shown, the pipeline high-viscosity chemical material efficient transportation and anti-clogging method of this invention is based on the closed-loop control concept. Through real-time acquisition, calculation and analysis of key operating parameters, and coordinated adjustment of the actuators, it actively suppresses the growth trend of the adhesion layer on the pipe wall. The specific process is as follows: First, in step S1, the control system 9 collects key parameters of the conveying process in real time. The collected data includes material temperature T, conveying flow rate Q, pipe wall shear stress τw_real, and pressure difference ΔP between the pipe inlet and outlet. Specifically, material temperature T is obtained by temperature sensor 3, conveying flow rate Q is obtained by flow meter 4, and pipe wall shear stress τw_real is obtained by shear stress sensor 6, or calculated back from the pipe pressure difference ΔP using a fluid dynamics model. The pressure difference ΔP is calculated by pressure sensors 5 located at both ends of the pipe. Simultaneously, the control system 9 determines the apparent viscosity μ(T) of the material under the current operating conditions based on temperature T and pre-calibrated rheological models or experimental data.

[0047] In step S2, the control system 9 calculates the nominal shear rate γ in the near-wall region based on the flow rate Q and the pipe inner diameter D. This shear rate characterizes the flow state of the fluid near the pipe wall and is an important parameter for subsequent calculations of the adhesion layer variation trend.

[0048] In step S3, the control system 9 calculates the rate of change of the virtual adhesion boundary layer thickness of the pipe wall based on the real-time acquired pipe wall shear stress τw_real, apparent viscosity μ(T), and shear rate γ, according to the following relationship: ; in, The thickness of the virtual adhesion boundary layer on the pipe wall. Its rate of change, Here, μ(T) is the adhesion property correction factor, μ(T) is the apparent viscosity at the current temperature T, and γ is the nominal shear rate in the near-wall region. This is the equivalent impedance coefficient for the growth of the adhesion layer.

[0049] Preferably, the apparent viscosity μ(T) is obtained by a pre-established material rheology model or experimental determination; the adhesion characteristic correction coefficient k and the equivalent impedance coefficient α are determined by calibration through material rheology tests and pipeline transportation tests.

[0050] In step S4, the control system 9 determines the rate of change of the adhesion layer. When When the value is positive and exceeds a preset threshold, it indicates that the adhesion layer on the pipe wall is in a growth state. Furthermore, it is preferable to combine the trend of the pipeline pressure difference ΔP for a comprehensive judgment. When the value is positive and the pressure difference ΔP shows a continuous upward trend, it is determined that the adhesion layer is in an effective growth state, thus avoiding misjudgment.

[0051] In step S5, when it is determined that the adhesion layer on the pipe wall is in a growth state, the control system 9 triggers the ultrasonic pulse generator 7 of the corresponding pipe section. Preferably, the ultrasonic pulse frequency is adjusted according to a preset relationship based on the ratio of the current pipe wall shear stress τw_real to the apparent viscosity μ(T), so that it can form a shear disturbance near the pipe wall that is adapted to the current flow state, thereby promoting the peeling of the unstable adhesion layer.

[0052] The ultrasonic pulse frequency Determined based on the following relationship: ; Where β is a dimensionless frequency correction coefficient.

[0053] In step S6, the control system 9 performs coordinated adjustment of the delivery parameters. Specifically, preferably, the intensity of the ultrasonic pulse is first increased, and the adjustment effect is observed within a set time. If the rate of change of the adhesion layer is still positive, the output of the delivery pump 8 is further adjusted to gradually increase the delivery flow rate Q and / or delivery pressure, thereby increasing the shear stress level of the pipe wall and improving the near-wall flow state. After each adjustment step, the control system 9 re-acquires and calculates the parameters. This is to achieve closed-loop control.

[0054] In step S7, the control system 9 performs a stability assessment of the adjustment effect. When the pipe wall shear stress τw_real reaches or approaches the target shear stress range, and the adhesion layer change rate... When the value drops to zero or negative, the system is considered to have entered a stable delivery state. This indicates that the adhesion layer on the pipe wall has stopped growing and may even be gradually thinning.

[0055] In step S8, if the system has reached a stable state, the control system 9 maintains the current conveying parameters and ultrasonic action state to ensure the continuous and stable operation of the conveying process; if the stable condition has not been reached, the system returns to steps S5 and S6 to continue adjustment until the stable condition is met.

[0056] The closed-loop control process constructed through the above steps enables the system to dynamically adjust based on the changing trend of the adhesion layer, and to actively intervene before the adhesion layer forms a serious blockage, thereby significantly improving the continuity and reliability of pipeline transportation of high-viscosity materials.

[0057] III. Key Parameters and Implementation Points In the implementation of this invention, the reasonable selection of key parameters and the implementation of control strategies have a significant impact on the stable operation and anti-blocking effect of the system, as detailed below: First, regarding the adhesion characteristic correction factor k, it is used to correct the deviation between the actual adhesion behavior of different materials at the pipe wall and the ideal rheological model. Since different high-viscosity materials differ in molecular structure, interfacial properties, and shear response, the value of k needs to be obtained through experimental calibration, preferably within the range of 0.85 to 1.20. In practical applications, it can be determined by fitting the results of pipeline transport tests or rotational rheometer measurements.

[0058] Secondly, the equivalent impedance coefficient of the adhesion layer growth This parameter characterizes the overall resistance experienced during the growth of the adhesion layer, and is closely related to material viscosity, pipe wall surface condition, and flow conditions. This parameter also needs to be obtained through experimental calibration, and its value directly affects the adhesion layer's rate of change. The calculation accuracy can be determined, preferably, by inverse analysis of pressure difference changes and adhesion layer thickness changes under different operating conditions. value.

[0059] Third, regarding the preset threshold The threshold value / dt_th is used to determine whether the adhesion layer has entered a significant growth stage. If the threshold is set too low, it may lead to frequent system adjustments and increased energy consumption; if the threshold is too high, it may delay intervention and increase the risk of blockage. Preferably, the threshold is set in the range of 0.005 to 0.02 mm / h, more preferably 0.01 mm / h.

[0060] Fourth, the arrangement of the ultrasonic pulse generators 7 has a significant impact on the anti-clogging effect. Preferably, they are arranged along the axial direction of the conveying pipeline 1 at intervals of 5 to 10 times the pipe diameter to create a uniform disturbance field along the entire length of the pipeline. Simultaneously, the frequency and intensity of the ultrasonic pulses should be adjusted according to real-time operating conditions. The frequency can be dynamically calculated based on the ratio of τw_real to μ(T), thereby improving adaptability to different viscosity states.

[0061] Fifth, regarding the control strategy, a graded, progressive closed-loop regulation method is preferred. Specifically, the adhesion layer should be disturbed first by increasing the intensity of the ultrasonic pulses. If the disturbance effect is insufficient, the conveying flow rate or conveying pressure should be gradually increased. This strategy helps to suppress the adhesion layer under low energy consumption conditions, while avoiding increased equipment load and changes in material properties due to excessive pressure increases.

[0062] Sixth, regarding the adjustment step size of the delivery parameters, it is preferable to set the adjustment step size of the ultrasonic pulse intensity to 5%–10%, and the adjustment step size of the delivery flow rate or pressure to 3%–5%, and maintain this step size for a certain period of time (e.g., 5–10 seconds) after each adjustment to observe the system response. By combining step-by-step adjustment with periodic sampling, system stability can be improved and control oscillations can be avoided.

[0063] Seventh, temperature control is a crucial prerequisite for ensuring stable system operation. The heating jacket 2 should control the material temperature within the viscosity-temperature operating range. This range must meet the following requirements: the material temperature is below the thermal degradation temperature, and within this temperature range, the material exhibits significant shear thinning characteristics. Through proper temperature control, viscosity can be reduced while maintaining stable material properties.

[0064] Eighth, the control system 9 is preferably implemented using an industrial controller or an embedded control system, which should have the capabilities of real-time data acquisition, high-speed computing, and multi-parameter linkage control. The system sampling period is preferably 1 to 30 seconds, and can be dynamically adjusted according to changes in operating conditions to reduce computational load while ensuring response speed.

[0065] Ninth, during system operation, safety constraints should be set, such as the maximum allowable pressure of the delivery pump and the maximum allowable temperature of the material. When the safety limit is reached, further increases in pressure and flow should be limited, and only ultrasonic pulse control should be maintained to ensure safe system operation.

[0066] By setting the key parameters and optimizing the implementation points, the present invention can achieve stable and efficient anti-blocking conveying under different material and working conditions, and has good engineering applicability and promotion value.

[0067] IV. Extended Explanation of Implementation Methods In practical engineering applications, the method described in this invention has good versatility and scalability, and can be flexibly adjusted and applied according to different material characteristics, pipeline structure forms and process requirements. Specifically, it includes the following extended implementation methods: Firstly, regarding applicable materials, this invention is not only suitable for typical high-viscosity materials such as epoxy resins, polymer melts, and adhesives, but can also be extended to high-concentration slurries, asphalt-like materials, and complex fluid systems with thixotropic or shear-thinning characteristics. For different materials with varying rheological properties, the adhesion characteristic correction coefficient k and the equivalent impedance coefficient α for adhesion layer growth can be pre-calibrated to adapt the adhesion layer change rate calculation model, thereby ensuring control accuracy.

[0068] Secondly, regarding pipeline structure, this invention is not only applicable to straight pipe conveying systems, but also to complex pipeline systems containing bends, diameter changes, or branch structures. In bends or areas with significant local flow disturbances, it is preferable to increase the arrangement density of the ultrasonic pulse generators 7 or increase the local control response frequency to enhance the ability to suppress adhesion layers in areas prone to accumulation.

[0069] Third, in terms of the implementation of the control system, the control system 9 of the present invention can adopt a centralized control or distributed control architecture. In long-distance transportation or large industrial equipment, a distributed control method is preferred, with local control units set up in different pipe sections to realize segmented monitoring and independent adjustment, while coordinated control is performed through a higher-level system, thereby improving the overall system response speed and control accuracy.

[0070] Fourth, regarding the expansion of control strategies, in addition to feedback control based on current parameters, predictive control mechanisms can be introduced. For example, by analyzing historical operating data, a model of the adhesion layer growth trend can be established, thereby adjusting the system in advance before the adhesion layer reaches the threshold, achieving a control method that combines feedforward and feedback, and further improving the system's anti-blocking capability.

[0071] Fifth, regarding the ultrasonic action mode, in addition to single-frequency pulses, multi-frequency superposition or modulated pulses can also be used to adapt to the peeling requirements under different adhesion states. Furthermore, each ultrasonic pulse generator 7 can be zoned and controlled according to the different operating conditions at different locations on the pipeline, thereby achieving more precise disturbance adjustment.

[0072] Sixth, regarding temperature control strategies, segmented heating can be combined to implement differentiated temperature control for different areas of the pipeline. For example, the temperature can be appropriately increased in pipe sections prone to adhesion, while maintaining a lower temperature in other areas, in order to reduce overall energy consumption while ensuring fluidity.

[0073] Seventh, regarding system safety and operation optimization, energy consumption monitoring and equipment status monitoring can be further integrated to optimize the scheduling of the operation of the delivery pump 8 and the ultrasonic pulse generator 7, reducing operating costs while ensuring the anti-blocking effect. Simultaneously, a multi-level alarm mechanism can be set up to issue timely warnings when the pressure difference abnormally increases or key parameters deviate from the set range.

[0074] Eighth, in industrial applications, the method of this invention can be integrated with existing production control systems, such as DCS (Distributed Control System) or PLC control systems, to achieve linkage control with upstream reaction processes or downstream processing processes, thereby forming a complete intelligent conveying solution.

[0075] Through the above-described various extended implementation methods, the present invention can adapt to the conveying needs of high-viscosity materials of different scales, materials and working conditions, further enhancing its practicality and promotional value.

[0076] V. Example 1: Anti-clogging control of high-viscosity epoxy resin delivery To further illustrate the technical solution of the present invention, the method of the present invention will be described in detail below with reference to specific embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0077] (1) Material and equipment parameters In this embodiment, industrial bisphenol A type epoxy resin is selected as the conveying material. The apparent viscosity of this material is about 2500 to 3500 Pa·s at 80°C. It has obvious shear thinning characteristics and strong pipe wall adhesion.

[0078] The structure of the conveying system is as follows Figure 1 As shown, the specific parameters are as follows: The conveying pipeline 1 has an inner diameter of DN50, a length of 12 m, and is made of stainless steel. Heating jacket 2 is used to maintain the pipeline temperature within the range of 60 to 100°C; The ultrasonic pulse generator 7 is arranged along the axial direction of the pipe, with an adjacent spacing of approximately 6 times the pipe diameter. The transfer pump 8 is a screw pump; Control system 9 is used to acquire parameters and perform closed-loop regulation.

[0079] The system is equipped with a temperature sensor 3, a flow meter 4, a pressure sensor 5, and a pipe wall shear stress sensor 6, which are used to obtain temperature T, flow rate Q, pressure difference ΔP, and pipe wall shear stress τw_real, respectively.

[0080] (2) Initial operating condition settings The target conveying flow rate Q_target is set to 0.45 m³ / h. The material temperature is controlled at 80℃ by heating jacket 2, which corresponds to an initial apparent viscosity μ(T) of approximately 3000 Pa·s.

[0081] The nominal shear rate γ in the near-wall region is calculated based on the flow rate Q and pipe diameter D, and is approximately 15–20 s. -1 .

[0082] Parameters were obtained in advance through experimental calibration: ; ; .

[0083] The threshold for the rate of change of the adhesion layer was set to 0.01 mm / h.

[0084] (3) Operation and control process After the system starts, the control system 9 collects and calculates relevant parameters in real time according to steps S1 to S3.

[0085] During the initial running phase: The change rate of the virtual adhesion boundary layer thickness on the pipe wall was calculated. This indicates that the adhesion layer has not grown; The pipeline pressure difference ΔP remains basically stable.

[0086] As the running time increases (approximately 3 hours later): Detected Increased to approximately +0.015 mm / h; At the same time, the pressure difference ΔP showed a continuous upward trend; Based on this, the control system 9 determines that the adhesion layer on the pipe wall has entered a growth state.

[0087] The following adjustment process is then performed: First, trigger the ultrasonic pulse generator 7 and adjust the pulse frequency according to the current working conditions. The frequency is approximately 20-30Hz. Secondly, the intensity of the ultrasonic pulse is gradually increased in increments of about 8%, with each adjustment lasting about 5 seconds. If the rate of change of the adhesive layer does not decrease significantly, further adjust the delivery pump 8 to increase the delivery flow rate by about 4% each time and maintain it for about 10 seconds; After each adjustment cycle, the control system re-acquires parameters and calculates... .

[0088] After approximately two adjustment cycles (about 60 seconds): The speed decreased to approximately -0.005 mm / h. The pressure difference ΔP stopped rising and decreased slightly; The system determined that the growth of the adhesion layer had been effectively suppressed and entered a stable operating state.

[0089] (4) Results of the operation Under the above control method, the system ran continuously for 72 hours without any blockage. Pipeline pressure differential fluctuations are controlled within ±5%. No obvious hard adhesion layer or scaling was observed; The conveying process was stable, and no material performance deterioration occurred due to local overheating.

[0090] (5) Explanation of implementation results This embodiment demonstrates that by calculating the change rate of the virtual adhesion boundary layer thickness on the pipe wall in real time and combining ultrasonic pulse action with closed-loop adjustment of transport parameters, the present invention can proactively intervene before the adhesion layer on the pipe wall forms significant accumulation, thereby inhibiting the continuous growth of the adhesion layer. Compared to simply increasing the transport pressure or raising the temperature, the present invention can reduce the risk of excessive local shear and heat accumulation while maintaining transport stability; compared to fixed-parameter ultrasonic action, the present invention can dynamically adjust the disturbance conditions according to the real-time rheological state; compared to methods that judge blockage based solely on changes in pipeline pressure difference, the present invention can reflect the growth trend of the adhesion layer in the near-wall region earlier, thereby improving continuous transport stability and anti-blockage effect.

[0091] VI. Comparative Example 1: Constant Pressure Delivery (No Closed-Loop Control) To compare and verify the effectiveness of the method of the present invention, Comparative Example 1 was set up. In this comparative example, the same materials, device structure and initial operating conditions as in Example 1 were used, but the adhesion layer change rate calculation and closed-loop control method described in the present invention were not used.

[0092] (1) Operating conditions The object being transported remains bisphenol A type epoxy resin; The inner diameter of the conveying pipeline 1 is DN50, and its length is 12 m; The material temperature is maintained at 80℃; The initial flow rate is set to 0.45 m³. 3 / h; Transfer pump 8 operates at a constant output pressure; The system does not enable the calculation of the pipe wall adhesion layer change rate, and does not perform... determination; Do not enable ultrasonic pulse generator 7; No dynamic adjustment of flow rate or pressure is performed.

[0093] (2) Operation process After the system starts up, the material is conveyed under constant pressure. In the initial stage, the flow state in the pipeline is relatively stable, and the pressure difference ΔP changes little.

[0094] As the running time increases (approximately 2-4 hours): As the low-shear zone persists in the pipe wall, the material gradually adheres to the pipe wall. The adhesion layer on the pipe wall gradually thickens, resulting in a reduction in the effective flow cross-sectional area; The pipeline pressure differential ΔP showed a continuous upward trend, with an increase of approximately 20% to 40%. At the same time, the transport flow rate decreased by about 10% to 15%.

[0095] Further operation (approximately 6-8 hours): There was significant accumulation of adhesive layer in some sections of the pipe. Some areas exhibit semi-cured or highly adhesive layer structures; The flow resistance in the pipeline has increased significantly, posing a clear risk of blockage. Ultimately, the machine must be shut down for manual cleaning or backflushing.

[0096] (3) Results of the operation During continuous operation: The system cannot operate stably for long periods of time and usually needs to be shut down for maintenance within 6 to 8 hours. The pipeline pressure differential continues to rise, with a large fluctuation range. There is a clear accumulation of adhesive layer; The efficiency of transportation decreases and energy consumption increases.

[0097] VII. Comparative Analysis of Results To further verify the technical effect of the method of the present invention, the operating results of Example 1 and Comparative Example 1 under the same material and working conditions were compared and analyzed.

[0098] Firstly, regarding continuous operation capability, when using the method of this invention, the rate of change of the adhesion layer on the pipe wall is measured. Real-time calculation and closed-loop regulation allow for intervention during the initial growth stage of the adhesion layer, ensuring it remains under control and enabling continuous operation for over 72 hours without clogging. In contrast, the comparative embodiment, lacking monitoring and control of the adhesion layer growth trend, typically exhibits significant clogging risk within 6-8 hours, necessitating shutdown and significantly reducing continuous operation capability.

[0099] Secondly, regarding pipeline pressure differential stability, the method of this invention maintains stable flow near the pipe wall by adjusting the ultrasonic pulse and transmission parameters in a coordinated manner, keeping the pipeline pressure differential ΔP within a range of ±5%. In contrast, in the comparative embodiment, as the adhesion layer thickens, the effective cross-sectional area of ​​the pipeline decreases, leading to a continuous increase in pressure differential, with fluctuations reaching 20% ​​to 40%, resulting in unstable system operation.

[0100] Third, in terms of the effect of adhesion layer control, the present invention uses the adhesion layer change rate as the core control index, so that the adhesion layer on the pipe wall is in a state of zero growth or negative growth for most of the operating time, making it difficult to form a stable accumulation structure; while the traditional constant pressure conveying method cannot effectively suppress adhesion in the low shear zone, resulting in the continuous accumulation and gradual hardening of the adhesion layer.

[0101] Fourth, in terms of energy consumption and operating efficiency, the method of the present invention avoids the problem of increased energy consumption caused by simply relying on increasing pressure or temperature through graded adjustment and on-demand control, and maintains a better energy consumption level while ensuring the anti-clogging effect; while in the comparative embodiment, due to the continuous increase in pressure difference, more energy needs to be consumed to maintain the flow rate, and the overall energy consumption increases significantly.

[0102] Fifth, in terms of process stability, this invention effectively reduces the risk of thermal degradation or performance deterioration of materials by avoiding excessive local shear and abnormal temperature rise; while traditional methods are prone to local imbalances when increasing pressure or temperature, affecting product quality.

[0103] In summary, the above comparison shows that the method of this invention, by introducing the quantifiable index of adhesion layer change rate and constructing a closed-loop control mechanism based on this index, achieves active regulation of the pipeline transportation process for high-viscosity materials. Compared with existing technologies, it can significantly improve the continuity, stability, and anti-clogging performance of the transportation process, and has good engineering application value.

[0104] The technical solution, specific embodiments, and effects of the present invention have been described in detail above with reference to the accompanying drawings. Those skilled in the art should understand that various equivalent substitutions or modifications can be made to the technical solution of the present invention without departing from the technical concept and essence of the present invention, and all such substitutions or modifications should fall within the protection scope of the present invention.

[0105] It should be noted that the embodiments described in this specification are merely illustrative of the technical concept of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, or combinations made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0106] Furthermore, the specific parameter ranges, numerical examples, and implementation conditions described in the specification are merely illustrative examples of preferred embodiments and do not constitute a limitation on the scope of protection of this invention. In practical applications, appropriate adjustments can be made according to different material characteristics, equipment conditions, and process requirements.

[0107] Finally, it should be noted that the parts of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A method for efficient pipeline transportation and anti-clogging of high-viscosity chemical materials, characterized in that, Includes the following steps: 1) During the conveying process, real-time data are collected on material temperature T, conveying flow rate Q, apparent viscosity μ(T), pipe diameter D, and pipe wall shear stress. And the pressure difference ΔP between the pipeline inlet and outlet; 2) Calculate the nominal shear rate γ in the near-wall region based on the flow rate Q and the pipe diameter D; 3) Calculate the rate of change of the virtual adhesion boundary layer thickness on the pipe wall according to the following formula: ; in, This is a correction factor for adhesion properties. δ is the equivalent impedance coefficient for adhesion layer growth; δ is the thickness of the virtual adhesion boundary layer on the pipe wall. 4) When the above When the value is positive and exceeds the preset threshold, it is determined that the adhesion layer on the pipe wall is in a growth state; 5) When it is determined that the adhesion layer on the pipe wall is in a growth state, the ultrasonic pulse generator installed on the delivery pipeline is triggered; 6) Simultaneously adjust the outlet pressure of the delivery pump and / or the delivery flow rate to adjust the change rate of the virtual adhesion boundary layer thickness on the pipe wall. The value is reduced to zero or negative, thereby inhibiting the growth of the adhesion layer on the pipe wall and achieving continuous anti-clogging transportation.

2. The method according to claim 1, characterized in that: The pulse frequency of the ultrasonic pulse generator The following relationship must be satisfied: ; in, This is a dimensionless frequency correction coefficient.

3. The method according to claim 1, characterized in that: The preset threshold is 0.005 mm / h to 0.02 mm / h.

4. The method according to claim 1, characterized in that: When determining whether the adhesion layer on the pipe wall is in a growth state, the trend of the pipeline pressure difference ΔP is also considered. When the value is positive and the pipeline pressure difference ΔP shows an upward trend, it is determined that the adhesion layer is in a state of continuous growth.

5. The method according to claim 1, characterized in that: The adjustment of the outlet pressure and / or flow rate of the delivery pump adopts a closed-loop control method, which includes: Based on the change rate of the virtual adhesion boundary layer thickness of the pipe wall Based on the calculation results, perform at least one of the following adjustment operations: a) Adjust the intensity of the ultrasonic pulse; b) Adjust the delivery flow rate; c) Adjust the delivery pressure; After the adjustment is completed, the parameters are re-acquired and calculated. The current state can be adjusted or maintained based on the recalculation results.

6. The method according to claim 5, characterized in that: The ultrasonic pulse intensity increases in increments of 5% to 10%, and / or the delivery flow rate increases in increments of 3% to 5%.

7. The method according to claim 1, characterized in that: The adjustment will stop and the current conveying state will be maintained when the following conditions are met: τw_real ≥ 0.9~0.95 × τw_target, and ≤ 0; Where τw_target is the target pipe wall shear stress.

8. The method according to claim 1, characterized in that: The ultrasonic pulse generators are spaced apart along the axial direction of the conveying pipe, and the distance between two adjacent ultrasonic pulse generators is 5 to 10 times the inner diameter of the pipe.

9. The method according to claim 1, characterized in that: The material temperature T is controlled within the viscosity-temperature operating range, which satisfies the following: 1) The material temperature is lower than the thermal degradation temperature; 2) Apparent viscosity decreases with increasing shear rate; 3) The near-wall shear rate is not lower than the preset critical shear rate; 4) Variation rate of virtual adhesion boundary layer thickness on pipe wall It can be controlled to be zero or negative.

10. The method according to claim 1, characterized in that: The adhesion property correction factor The value range is 0.85 to 1.20, and the equivalent impedance coefficient of the adhesion layer growth is... The calibration was determined based on material rheology tests and pipeline transportation tests.

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