Long-distance multi-stage pressurizing pneumatic conveying anti-erosion pipeline system

Abstract

The utility model discloses a long-distance multi-stage pressurizing pneumatic conveying anti-erosion pipeline system, which is characterized in that a plurality of stages of pipelines are connected through an elbow with an anti-wear bowl-shaped structure, and a pressurizing pipeline is arranged at the elbow to realize a multi-stage pressurizing conveying effect, so that the conveying efficiency of a long-distance pipeline is ensured. The design method comprises the steps that CFD-DEM-based numerical simulation is adopted to obtain gas-solid two-phase flow characteristics under different working conditions, the product of the collision force of particles and the wall face and the number of collision times of the particles and the wall face is adopted as a quantitative evaluation index of the pipeline abrasion degree, and finally an empirical correlation formula of structure parameters, material parameters and the pipeline abrasion degree is obtained. And optimal structure parameters and process parameters under the lowest energy consumption and abrasion loss are further obtained. High-speed particles are prevented from directly impacting the inner wall of a pipeline, abrasion is reduced, and the purpose of low-consumption, abrasion-resistant and long-distance pneumatic conveying is achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of pneumatic conveying equipment, and particularly relates to a long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system and a design method thereof. Background Technique

[0002] Tin smelting technology refers to the process of extracting tin from tin ore and purifying it through a series of physical and chemical means; the main way of feeding materials into the furnace in the conventional tin smelting process is belt transportation. However, serious particle dispersion occurs during belt transportation, which will not only cause low-altitude pollution but also consume raw materials and reduce the metal recovery rate. As an alternative method, the basic process of pneumatic conveying is to use air as the carrying medium to transport materials from one place to another. Pneumatic conveying is widely used in the transportation of solid materials due to its flexible and variable pipeline layout, space saving, low maintenance cost, and less environmental pollution. However, in tin smelting, the conveying distance into the furnace is long, and the long-distance pneumatic conveying process is affected by momentum attenuation, which may lead to a reduction in conveying efficiency. In addition, pipeline wear is also a serious problem, which may shorten the service life of the conveying system. The wear area of the pneumatic conveying pipeline is mainly concentrated at the pipeline inlet and elbows. Therefore, there is an urgent need for a new system to achieve a low-consumption and anti-wear long-distance pneumatic conveying process.

[0003] Chinese Patent CN202311553494.1 discloses a positive pressure pneumatic conveying device and a positive pressure pneumatic conveying method; the wear area of its pneumatic conveying pipeline is mainly concentrated at the pipeline inlet and elbows, and pipeline wear is also a serious problem, which may lead to a shortening of the service life of the conveying system and an increase in the use cost.

[0004] Chinese Patent CN202111256304.0 discloses a pneumatic conveying system for sheet materials and a pneumatic conveying method. Although it successfully applies pneumatic conveying to the field of sheet material conveying. However, the long-distance pneumatic conveying process is affected by momentum attenuation, resulting in a reduction in conveying efficiency, an increase in the cost of pneumatic conveying, and a decrease in conveying efficiency.

[0005] Chinese Patent CN202311046914.7 discloses a pneumatic conveying system, which has low requirements for the fan, simple overall structure, and improved feeding efficiency. However, the long-distance pneumatic conveying process will be affected by momentum attenuation, resulting in a reduction in conveying efficiency.

[0006] Currently, the existing technology has problems that when the conveying distance into the furnace is long, the long-distance pneumatic conveying process is affected by momentum attenuation, resulting in a reduction in conveying efficiency; pipeline wear may lead to a shortening of the service life of the conveying system; and the wear area of the pneumatic conveying pipeline is mainly concentrated at the pipeline inlet and elbows.

[0007] Therefore, how to provide a long-distance multi-stage pressurized pneumatic conveying erosion-resistant pipeline system and its control method is an urgent problem to be solved by those skilled in the art. Content of the Utility Model

[0008] In view of this, the present utility model provides a long-distance multi-stage pressurized pneumatic conveying erosion-resistant pipeline system and a design method to solve the problems in the prior art that during the long-distance pneumatic conveying process, the conveying efficiency is reduced due to the influence of momentum attenuation, and the service life of the conveying system is shortened due to pipeline wear.

[0009] To achieve the above object, the present utility model adopts the following technical solution: A long-distance multi-stage pressurized pneumatic conveying erosion-resistant pipeline system, which includes:

[0010] A conveying pipeline, the conveying pipeline has multiple sections, and the multiple sections of the conveying pipeline are used to extend the pneumatic conveying distance of the material;

[0011] Connecting elbows, there are multiple groups of connecting elbows and are used to connect adjacent sections of the conveying pipeline, the connecting elbows are used to adjust the pneumatic conveying direction, and a bowl-shaped structure for preventing the material from impacting the inner wall of the pipeline is provided on the connecting elbows;

[0012] A pressurizing pipeline, the pressurizing pipeline is connected at at least one connecting elbow, and the blowing direction of the pressurizing pipeline is arranged parallel to the direction of the downstream conveying pipeline.

[0013] The beneficial effects of the present utility model are as follows: Multiple sections of the conveying pipeline can extend the conveying distance of the material. The use of connecting elbows to connect multiple sections of the conveying pipeline can optimize the conveying line and realize a flexible pipeline layout for long-distance conveying. Arranging a pressurizing pipeline at the connecting elbow to provide the conveying power of the material can extend the pneumatic conveying distance and improve the conveying efficiency. The structure of the pressurizing pipeline can be increased according to the conveying distance. In addition, in order to reduce the wear of the material on the elbow, a bowl-shaped structure is provided at the connecting elbow, and the accumulation of the material at the bowl-shaped structure is used to provide a protective layer, thereby avoiding the material directly impacting the pipeline and improving the service life of the conveying system.

[0014] Preferably, an inlet pipeline is connected to the upstream of the conveying pipeline, an air compressor is connected to the inlet pipeline, the inlet pipeline includes a connecting pipe and a quick-release pipe, one end of the connecting pipe is connected to the conveying pipeline, the other end of the connecting pipe is detachably connected to one end of the quick-release pipe, and the other end of the quick-release pipe is connected to an external air compressor.

[0015] The resulting technical effects are as follows: The inlet pipeline is connected to an air compressor to provide the initial conveying power for the materials. The inlet pipeline is composed of a connecting pipe and a quick-release pipe, which facilitates the installation and maintenance of the pipeline, improves the usability and maintainability of the pipeline; makes the installation and maintenance of the pipeline more convenient and efficient, reduces the downtime caused by maintenance operations, and improves production efficiency.

[0016] Preferably, on the outer side wall of the connecting pipe and near the other end, there are multiple buckle grooves, the buckle grooves are parallel to the axial direction of the connecting pipe, on the outer side wall of the connecting pipe and near the end of the buckle grooves, there is a limit groove, the limit groove communicates with the buckle groove and is vertically arranged, on one end edge of the outer side wall of the connecting pipe, there is a pin hole, and on one end of the inner side wall of the quick-release pipe, there are multiple buckles, and the buckles enter the limit groove through the buckle grooves, and on one end of the outer side wall of the quick-release pipe, there is a pin hole that cooperates with the pin hole.

[0017] The resulting technical effects are as follows: The connecting pipe and the disassembly pipe can be quickly disassembled and assembled. Through the design of the pin hole, the connected pipeline is more firm and stable, reducing the risk of loosening caused by vibration or other reasons, and improving the safety of equipment operation.

[0018] Preferably, the connecting elbow includes a first type of connecting elbow and a second type of connecting elbow. The bending angle of the first type of connecting elbow is 90°, and the bending angle of the second type of connecting elbow is 135°. The first type of connecting elbow and the second type of connecting elbow are arranged alternately in sequence, and both ends of the first type of connecting elbow and the second type of connecting elbow are connected to a conveying pipeline.

[0019] The resulting technical effects are as follows: The two types of elbows can achieve an optimized layout of the conveying line. The 90-degree and 135-degree elbows make the streamline of the air inlet channel smoother, which is beneficial to reducing resistance, lowering flow losses, and improving conveying efficiency.

[0020] Preferably, a pressurizing pipeline is connected to the second type of connecting elbow, and an air compressor is connected to each pressurizing pipeline. The multiple pressurizing pipelines and the multiple air compressors form a multi-stage pressurized conveying mode and increase the number of propulsion stages according to the length of the conveying distance.

[0021] The resulting technical effects are as follows: Arranging the pressurizing pipeline on the second type of connecting elbow, and the direction of the conveying pipeline is parallel to the injection direction, which can reduce power loss and also reduce the impact wear of the materials on the pipeline.

[0022] Preferably, a bowl-shaped structure with a locally thickened deformation is provided on the concave side of both the first type of connecting elbow and the second type of connecting elbow.

[0023] The resulting technical effect is that this structure can form a protective layer during material transportation to avoid the direct impact of the material on the pipeline at the turning point, thereby increasing the service life of the pipeline.

[0024] The present utility model also discloses a design method for a long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system, which is applied to the above-mentioned long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system. It includes: obtaining the flow characteristics of gas-solid two-phase materials under different working conditions by using numerical simulation based on CFD-DEM, using the product of the collision force between particles and the wall and the number of collisions between particles and the wall as a quantitative evaluation index for the pipeline wear degree, finally obtaining an empirical correlation formula of structural parameters, material parameters and pipeline wear degree, and further obtaining the optimal structural parameters and process parameters under the lowest energy consumption and wear amount.

[0025] Preferably, it further includes: constructing a model of the conveying pipeline in a 1:1 equal proportion, dividing the calculation grid of the constructed model, and selecting the numerical model and numerical method of pneumatic conveying;

[0026] According to the production situation, given the density and viscosity physical property parameters of particles and air substances, given the conveying speed and inlet pressure, and outlet pressure boundary conditions;

[0027] Processing the results calculated by the numerical simulation system to obtain the input condition values and the output wear quantification values;

[0028] Fitting multiple groups of input-output values to obtain an empirical formula for wear quantification.

[0029] Preferably, simulating the interaction between particle motion and fluid, optimizing the design of the conveying pipeline, analyzing the influence of various process parameters of pneumatic conveying, and obtaining an empirical formula for wear quantification; through numerical simulation methods, assisting engineers in designing and optimizing the pneumatic conveying system; combining CFD and DEM methods to predict the performance of the pneumatic conveying system, including key parameters such as particle distribution and flow velocity distribution.

[0030] Preferably, by fitting multiple groups of input-output values, an empirical formula for wear quantification is obtained, and the relationship between input parameters and output wear amount is expressed through a mathematical model to achieve quantitative description of data; the empirical formula quantitatively describes wear quantification, predicts the wear amount under different parameters, and optimizes process parameters and structural parameters based on this, reducing pipeline wear from the source.

[0031] The beneficial effect of the present utility model is that it can optimize multiple parameters including pneumatic conveying wind pressure, flow rate, particle diameter, and particle mass flow rate, and reduce pipeline wear from the source and extend the service life of the conveying system by adjusting the flow pattern and flow state of gas-solid two-phase motion and using the collision frequency and collision force magnitude as quantitative evaluation indicators. Description of the Drawings

[0032] Figure 1 Structural diagram of a long-distance multi-stage pressurized pneumatic conveying erosion-resistant pipeline system of the present utility model;

[0033] Figure 2 Structural diagram of the inlet pipeline of a long-distance multi-stage pressurized pneumatic conveying erosion-resistant pipeline system of the present utility model;

[0034] Figure 3 Schematic diagram of the design method of a long-distance multi-stage pressurized pneumatic conveying erosion-resistant pipeline system of the present utility model.

[0035] 1 Conveying pipeline, 2 Connecting elbow, 21 First type of connecting elbow, 22 Second type of connecting elbow, 23 Bowl-shaped structure, 3 Pressurizing pipeline, 4 Inlet pipeline, 41 Connecting pipe, 42 Quick-release pipe, 43 Snap groove, 44 Limit groove, 45 Pin hole, 46 Snap, 47 Pin hole, 5 Air compressor. Specific implementation mode

[0036] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0037] Refer to the appendix of the present utility model Figures 1 to 3 , according to an embodiment of the present utility model, a long-distance multi-stage pressurized pneumatic conveying erosion-resistant pipeline system includes:

[0038] Conveying pipeline 1, there are multiple sections of the conveying pipeline 1, and the multiple sections of the conveying pipeline 1 are used to extend the pneumatic conveying distance of the material; it can be adaptively arranged according to the length of the conveying distance;

[0039] Connecting elbow 2, there are two types of connecting elbows 2 used in this embodiment, one is a 90-degree elbow, and the other is a 135-degree elbow. The elbows are used to connect adjacent conveying pipelines to realize the flexible layout of the conveying line. The connecting elbow 2 is used to adjust the pneumatic conveying direction. A bowl-shaped structure 23 for preventing the material from impacting the inner wall of the pipeline is provided on the connecting elbow 2 to weaken the erosion damage degree of the granular material to the pipeline;

[0040] Pressurizing pipeline 3, the pressurizing pipeline 3 is connected at at least one connecting elbow 2, and the blowing direction of the pressurizing pipeline 3 is arranged parallel to the direction of the downstream conveying pipeline, so as to maximize the energy of the airflow and avoid energy loss.

[0041] Conventional pressurized gas injection schemes usually have an opening on one side of the pipeline and inject gas under pressure vertically, which can lead to excessive local air flow impact. While eroding and wearing the local pipeline of the booster, it also fails to fully utilize the air supplement energy. In contrast, the present utility model sets the booster inlet at the elbow, reducing losses when two high-pressure air flows converge. At the same time, the blowing direction of the booster pipeline is parallel to the direction of the downstream conveying pipeline, weakening the particle erosion and wear of the pipeline.

[0042] Specifically, an inlet pipeline 4 is connected to the upstream of the conveying pipeline 1, and an air compressor 5 is connected to the inlet pipeline 4. The inlet pipeline 4 includes a connecting pipe 41 and a quick-release pipe 42. One end of the connecting pipe 41 is connected to the conveying pipeline 1, and the other end of the connecting pipe 41 is detachably connected to one end of the quick-release pipe 42. The other end of the quick-release pipe 42 is connected to an external air compressor. Through the detachable design, it is convenient to install and maintain the pipeline, improving the usability and maintainability of the pipeline; making the installation and maintenance of the pipeline more convenient and efficient, reducing the downtime caused by maintenance operations, and enhancing production efficiency. The connecting pipe 41 connects different parts of the pipeline components, ensuring the integrity and sealing of the pipeline; ensuring that there are no air leaks or leaks during the operation of the pipeline, and guaranteeing the smooth progress of the production process.

[0043] More specifically, multiple buckle channels 43 are provided on the outer side wall of the connecting pipe 41 and near the other end. The buckle channels 43 are parallel to the axial direction of the connecting pipe 41. A limiting groove 44 is provided on the outer side wall of the connecting pipe 41 and near the end of the buckle channels 43. The limiting groove 44 communicates with the buckle channels 43 and is vertically arranged. An insertion port 45 is provided at one end edge of the outer side wall of the connecting pipe 41. Multiple buckles 46 are provided at one end of the inner side wall of the quick-release pipe 42. The layout of the buckles needs to correspond to the distribution of the buckle channels, otherwise it cannot be inserted smoothly. The multiple buckles are evenly distributed in the circumferential direction. The buckles 46 enter the limiting groove 44 through the buckle channels 43 and are rotated into place. A pin hole 47 that cooperates with the insertion port 45 is provided at one end of the outer side wall of the quick-release pipe 42. Finally, a pin is inserted into the corresponding pin hole and insertion port to realize the connection between the connecting pipe and the quick-release pipe. The present utility model can be quickly installed and unlocked, improving the efficiency and convenience of installation; reducing the manual operation time during the pipeline installation process, reducing the assembly cost and enhancing production efficiency. The insertion port 45 fixes the pipeline components, ensuring the stability and safety of the connection; through the design of the insertion port, the connected pipeline is made more firm and stable, reducing the risk of loosening caused by vibration or other reasons, and improving the safety of equipment operation.

[0044] In the present utility model, the first type of connecting elbow 21 and the second type of connecting elbow 22 are arranged alternately in sequence, and can also be adaptively adjusted according to the actual line requirements. Both ends of the first type of connecting elbow 21 and the second type of connecting elbow 22 are connected to the conveying pipeline 1.

[0045] The utility model is mainly connected to the boost pipeline 3 on the second type connecting elbow 22. Considering that the angle of the second type connecting elbow is larger, it is easy to arrange and it is also easy to converge the two airflows to achieve the effect of superimposed transportation. It should be noted that the angle of the second type connecting elbow is 135 degrees, which has a certain advance guiding effect. That is to say, the boost pipeline does not vertically converge the upstream airflow, but obliquely realizes the convergence of the two airflows, which is conducive to giving full play to the energy of the airflow and avoiding the loss of the two airflows due to mutual impact.

[0046] Each boosting pipeline 3 is connected to an air compressor 5. Multiple boosting pipelines 3 and multiple air compressors 5 form a multi-stage boosting delivery mode and increase the number of propulsion stages according to the length of the delivery distance.

[0047] In the utility model, the concave sides of the first type connecting elbow 21 and the second type connecting elbow 22 are both provided with a partially thickened and deformed bowl-shaped structure 23, where the granular materials are accumulated and form a protective layer, which can prevent the granular materials from directly corroding the pipeline. Conventional pneumatic conveying often causes severe scouring and wear at the elbow.

[0048] The specific booster delivery process is:

[0049] The gas is emitted by the upstream air compressor, enters the primary delivery pipeline through the inlet pipeline 4, enters the subsequent delivery pipeline after passing through the first type connecting elbow 21, and is then transported downward through the second type connecting elbow 22 from the subsequent delivery pipeline. At this time, the second type connecting elbow is connected to the boosting pipeline 3, and the blowing direction of the boosting pipeline is parallel to the downstream delivery pipeline. The gas in the boosting pipeline enters the second type connecting elbow and intersects with the upstream gas, and then enters the downstream delivery pipeline after merging, and so on, to achieve multi-stage boosting and transportation.

[0050] It should be noted that the utility model can adopt a vertical connection method (attached Figure 1 ), a horizontal connection method can also be used. When the pipeline is connected horizontally, the connection method is the same as the vertical connection method of this embodiment. The number of propulsion stages is increased according to the length of the conveying distance. By dividing it into different propulsion stages, the working principle and flow characteristics of the entire pipeline system can be better understood, which helps to optimize the pipeline design, reduce energy consumption, reduce wear and ensure the stable operation of the system.

[0051] In summary, the present utility model enables the entire inlet pipeline system to achieve rapid installation, disassembly, and maintenance, improves the reliability and operability of the pipeline, reduces potential failure risks and maintenance difficulties. By optimizing the pipeline structure design, it can reduce production costs, improve production efficiency, and ensure the safe operation of the pipeline system, which is of great significance for the smooth progress of the industrial production process. The inlet pipe structure is designed for convenient disassembly. When the inlet pipeline is severely worn, the inlet section can be disassembled and replaced separately. The connection method based on buckles can increase the disassembly and replacement efficiency.

[0052] The present utility model also provides an embodiment of a control method for a long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline. In this embodiment, the control method for a long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline is applied to the long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system as described in the above embodiment. The control method for a long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline specifically includes the following steps:

[0053] Step S1: The gas is emitted from the upstream air compressor, enters the first-stage conveying pipeline through the inlet pipeline, and enters the subsequent connecting pipeline after passing through the first type of connecting elbow.

[0054] Step S2: When the gas passes through the second type of connecting elbow in the connecting pipeline, the gas emitted from the air compressor on the near side enters the anti-wear bowl-shaped structure through the pressurizing pipeline and converges with the gas entering from the connecting pipeline. After convergence, it enters the next-stage conveying pipeline.

[0055] Step S3: When passing through the anti-wear bowl-shaped structure at the next second type of connecting elbow, it converges with the gas entering from the pressurizing inlet of the air compressor on the near side and enters the pressurizing pipeline of this stage.

[0056] The design method of the long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system provided in this embodiment uses numerical simulation based on CFD-DEM to obtain the flow characteristics of gas-solid two-phase under different working conditions. The product of the collision force between particles and the wall and the number of collisions between particles and the wall is used as a quantitative evaluation index for the pipeline wear degree. Finally, an empirical correlation formula of structural parameters, material parameters, and pipeline wear degree is obtained, and further the optimal structural parameters and process parameters under the lowest energy consumption and wear amount are obtained. Specifically, it includes the following steps:

[0057] Step S4: Build a model of the conveying pipeline at a 1:1 ratio, divide the calculation grid for the built model, and select the numerical model and numerical method for pneumatic conveying.

[0058] Step S5: According to the production situation, give the physical property parameters such as the density and viscosity of substances such as particles and air, and give the boundary conditions such as the conveying speed, inlet pressure, and outlet pressure.

[0059] Step S6: Process the results calculated by the numerical simulation system to obtain the input condition values and the output wear quantification values;

[0060] Step S7: Fit multiple sets of input-output values to obtain an empirical formula for wear quantification.

[0061] In step S4 of this embodiment, a numerical simulation model of the conveying pipeline is constructed, the calculation grid is reasonably divided, and a numerical model and method suitable for pneumatic conveying analysis are selected; through the construction of the numerical simulation model and grid division, the motion states of the fluid and particles in the conveying pipeline can be accurately simulated, providing reliable basic data for subsequent optimization and analysis. In step S5, physical property parameters, conveying speed, and boundary conditions are given to establish a numerical simulation calculation model of the conveying pipeline; by accurately giving physical property parameters and boundary conditions, various process parameters in the actual conveying process can be simulated, which helps to accurately simulate the operating conditions of the pneumatic conveying system. In step S6, the results of the numerical simulation calculation are processed, the conveying parameters and wear conditions obtained from the simulation are analyzed, and the output results are quantified; by processing the simulation results, the influence degree of each process parameter on wear can be analyzed, providing a basis for subsequent optimization and adjustment, and realizing effective monitoring and control of the wear condition of the conveying pipeline. In step S7, through fitting analysis of multiple sets of input-output values, an empirical formula for wear quantification is obtained; establishing an empirical formula for wear quantification can quickly calculate the wear condition according to various process parameters of the conveying pipeline, providing quantitative guidance for the subsequent optimization of process parameters, and improving the service life and stability of the pipeline (for the specific principle, refer to Appendix Figure 3 ).

[0062] Through the above steps, this embodiment of the process parameter optimization method for a multi-stage supercharged pushing pipeline can analyze and optimize the process parameters of the pneumatic conveying system by means of numerical simulation technology, so as to improve the efficiency and stability of the system, and reduce wear loss and maintenance costs. It will provide a scientific basis for the design, optimization, and operation of the pneumatic conveying system, and realize the efficient, stable, and reliable operation of the system.

[0063] The wear of the pipeline in this embodiment depends to a great extent on the motion state of the particles in the pipeline. The particle flow pattern and flow regime are affected by various factors, such as the pressure and flow rate of the injection gas, the particle ratio, the particle diameter, the particle density, the gas-solid ratio, the size and shape of the pipeline, etc. In this embodiment, numerical simulation based on CFD-DEM is used to obtain the flow characteristics of gas-solid two-phase under different working conditions. During the calculation process, the pressure and flow rate of the injection gas, the particle ratio, the particle diameter, the particle density, the gas-solid ratio, the size and shape of the pipeline are used as independent variables, and the product of the collision force between the particle and the wall and the number of collisions between the particle and the wall is used as a quantitative evaluation index for the pipeline wear degree. Finally, an empirical correlation formula for the structural parameters, material parameters and pipeline wear degree is obtained, and the optimal structural parameters and process parameters under the lowest energy consumption and wear amount are further obtained.

[0064] Furthermore, in step S4, a numerical model and numerical method suitable for pneumatic conveying are selected. The specific selection reasons and detailed numerical models are as follows:

[0065] Computational Fluid Dynamics - Discrete Element Method (CFD-DEM) can accurately simulate particle motion, the interaction between particles and fluids, and complex mechanical properties; simulate the phenomena of particle accumulation and separation in fluid media, track the motion trajectories of particles, and calculate the fluid forces received by particles. In the CFD-DEM coupling method, solid particles are regarded as the discrete phase, and their translational and rotational motions are described by Newton's second law:

[0066]

[0067] where, v i and ω i represent the translational velocity and rotational velocity of the particle; m i , F cij , F pi and F di represent the mass, contact force, pressure gradient force and drag force of the particle respectively; the contact force between particles or between particles and the wall is calculated by the soft-sphere contact model, and the collision force received by each particle is as follows:

[0068]

[0069] The pressure gradient force is the force acting on the particle due to the uneven distribution of partial pressure, and its calculation formula is as follows:

[0070]

[0071] The Gidaspow drag model is used to calculate the drag force received by each particle. This model couples the Wen-Yu model and the Ergun model, and the calculation formula is as follows:

[0072]

[0073] Among them, D1 and D2 represent the Wen-Yu drag model and the Ergun drag model respectively

[0074]

[0075] C1 and C2 are constants, and their values are 180 and 2 respectively; in addition, C d The calculation formula is as follows:

[0076]

[0077] In the CFD-DEM method, the gas phase is regarded as a continuous phase, and its mass conservation and momentum conservation formulas are as follows:

[0078]

[0079] In the above equations, ρ g , p, u, μ are the density, pressure, velocity vector and dynamic viscosity of the fluid phase respectively, and g is the acceleration of gravity;

[0080] is the local void fraction of the current calculation cell, where n is the total number of particles located in the cell, and ΔV is the volume of the current calculation cell. S p is the total value of the momentum source term in the current cell, which can be estimated as:

[0081]

[0082] Among them, f p , f d are the pressure gradient force and the drag force respectively;

[0083] μ t is the turbulent viscosity. For a dense-phase pneumatic conveying system, the standard k-ε turbulent model can accurately simulate the turbulent state in the system and reduce the calculation time and resource consumption while ensuring the accuracy of the results. Its estimation is:

[0084] μ t = c μ ρ g k 2 / ε t (13)

[0085] Among them, c μ (= 0.09) is the model constant, k is the turbulent kinetic energy, and ε t is the turbulent dissipation rate. The transport equations of k and ε t can be expressed as:

[0086]

[0087] Among them, the model constants are c1 and c2, with values of 1.44 and 1.92 respectively, and the turbulent Prandtl numbers are σ ε and σ k , and their values are 1.44 and 1.92 respectively.

[0088] In summary, this embodiment accurately simulates particle motion and the interaction between particles and fluids.

[0089] CFD-DEM can accurately simulate the motion trajectories of particles in gas flow, including the interactions between particles and the interactions between particles and fluids. Simulate the flow patterns of gas-solid two-phase flows to provide reliable simulation data for system design and optimization. Calculate complex mechanical properties, describe the translational and rotational motions of particles through Newton's second law, and consider mechanical properties such as contact forces, pressure gradient forces, and drag forces to achieve more realistic simulation. The empirical formula for wear quantification states that by adjusting the flow pattern of the fluid, that is, changing the flow state and flow mode of the fluid in the pipeline, the wear of the system can be effectively reduced; various methods are used to adjust the flow pattern, such as changing the pipeline design, adding deceleration devices, improving the pipeline connection method, etc., to reduce the impact and friction of the fluid inside the pipeline and reduce the degree of wear. By optimizing the flow pattern, the gas can flow more evenly in the pipeline, reducing the wear caused by velocity gradients and unstable flow patterns, thereby extending the life of the pipeline and equipment and reducing maintenance costs; reducing wear by adjusting the flow pattern of the fluid is an effective optimization method that can reduce the degree of wear and improve the stability and efficiency of the system on the premise of ensuring the normal operation of the system.

[0090] This embodiment improves the system stability and efficiency: By accurately simulating particle motion and fluid interaction, the design of the conveying pipeline can be optimized, improving the system stability and conveying efficiency. Reduce the wear of the pneumatic conveying system: Analyze the influence of various process parameters to obtain an empirical formula for wear quantification, which helps to reduce the wear loss of the pneumatic conveying system and extend the equipment life. Assist in engineering design and optimization: Through numerical simulation methods, it can assist engineers in designing and optimizing the pneumatic conveying system, discover problems in advance and make improvements, saving design costs and time. Accurately predict system performance: Combining CFD and DEM methods can more accurately predict the performance of the pneumatic conveying system, including key parameters such as particle distribution and flow velocity distribution, which helps to improve the reliability and stability of system operation.

[0091] In summary, this embodiment uses the CFD-DEM method to perform numerical simulation of pneumatic conveying, which can achieve accurate simulation and prediction of the complex characteristics of the system, providing important technical support for the design, optimization, and operation of the pneumatic conveying system. Through the coupling of CFD and DEM, solving calculations are carried out in the numerical simulation system, and a scenario approximate to the actual work can be simulated.

[0092] Further, in step S7, a wear quantification empirical formula is obtained by fitting multiple sets of input and output values. The fitting formula is as follows:

[0093] A = polyfit(xdata, ydata, n) (16)

[0094] The empirical formula for pipeline wear quantification can be expressed by the following formula:

[0095] W = f(u, M, L, D1, D2, D3, P, d, ρ, ∈) (17)

[0096] Where u, M, L, D1, D2, D3, P, d, ρ, and ∈ respectively represent gas flow rate, solid flow rate, pipeline length, pipeline diameter, elbow diameter, spherical structure diameter, conveying pressure, particle size, particle density, and particle sphericity.

[0097] In summary, the fitting quantification model of this embodiment: By fitting multiple sets of input and output values, an empirical formula for wear quantification (formula 17) is obtained, which can express the relationship between input parameters and output wear amount through a mathematical model, realizing the quantitative description of data. Parameter correlation and influence formula: The relationship between each parameter (gas flow rate, solid flow rate, pipeline length, etc.) in the empirical formula and the pipeline wear amount helps to reveal the influence degree of each parameter on the wear degree, providing a basis for subsequent optimization and control. Prediction and optimization: The empirical formula quantitatively describes the wear quantification, can predict the wear amount under different parameters, helps to optimize the design of the conveying pipeline and parameter setting, and reduces system wear and loss. Improve system stability: By studying and applying the wear quantification formula, the wear degree of the system can be better controlled, the stability and life of the system can be improved, and the system maintenance frequency can be reduced. Reduce trial-and-error costs: Using the empirical formula for prediction and optimization can reduce trial-and-error costs, save time and resources, and make the design and operation of the pneumatic conveying system more efficient and reliable. Improve engineering design efficiency: The wear quantification empirical formula provides quantitative guidance for engineers, helps to determine the influence degree of the key parameters of the system on wear, and helps to design and optimize quickly and accurately.

[0098] In summary, this embodiment realizes the quantitative description and prediction of the wear situation of the pneumatic conveying system by fitting the wear quantification empirical formula, provides important technical support for the design, optimization, and operation of the system, helps to reduce system wear and maintenance costs, and improves the reliability and efficiency of the system. After calculation, the empirical correlation formula of the structural parameters, material parameters, and pipeline wear degree is finally obtained, and the optimal structural parameters and process parameters under the lowest energy consumption and wear amount are further obtained.

[0099] In several embodiments provided by the present utility model, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces, and the indirect coupling or communication connection of devices or units can be in electrical, mechanical, or other forms.

[0100] Regarding the devices and usage methods disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For related parts, reference can be made to the description in the method section.

[0101] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present utility model. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present utility model. Therefore, the present utility model will not be limited to these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system, characterized in that: include: A conveying pipeline (1), wherein the conveying pipeline (1) has multiple sections, and the multiple sections of the conveying pipeline (1) are used to extend the pneumatic conveying distance of the material; A connecting elbow (2), wherein the connecting elbow (2) has multiple groups and is used to connect adjacent sections of the conveying pipeline (1), the connecting elbow (2) is used to adjust the pneumatic conveying direction, and the connecting elbow (2) is provided with a bowl-shaped structure (23) for preventing the material from impacting the inner wall of the pipeline; A boosting pipeline (3), the boosting pipeline (3) is connected to at least one connecting elbow (2), and the blowing direction of the boosting pipeline (3) is arranged in parallel with the direction of the downstream delivery pipeline.

2. The long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system according to claim 1 is characterized in that: An inlet pipeline (4) is connected upstream of the delivery pipeline (1), and the inlet pipeline (4) is connected to an air compressor (5). The inlet pipeline (4) comprises a connecting pipe (41) and a quick-release pipe (42). One end of the connecting pipe (41) is connected to the delivery pipeline (1), and the other end of the connecting pipe (41) is detachably connected to one end of the quick-release pipe (42). The other end of the quick-release pipe (42) is connected to an external air compressor.

3. The long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system according to claim 2 is characterized in that: A plurality of buckle grooves (43) are provided on the outer wall of the connecting tube (41) and near the other end. The buckle grooves (43) are parallel to the axial direction of the connecting tube (41). A limiting groove (44) is provided on the outer wall of the connecting tube (41) and near the end of the buckle groove (43). The limiting groove (44) is communicated with the buckle groove (43) and arranged vertically. A latch hole (45) is provided on the edge of one end of the outer wall of the connecting tube (41). A plurality of buckles (46) are provided on one end of the inner wall of the quick-release tube (42). The buckles (46) enter the limiting grooves (44) through the buckle grooves (43). A pin hole (47) matching the latch hole (45) is provided on one end of the outer wall of the quick-release tube (42).

4. The long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system according to claim 1 is characterized in that: The connecting elbow (2) comprises a first-type connecting elbow (21) and a second-type connecting elbow (22); the bending angle of the first-type connecting elbow (21) is 90°, and the bending angle of the second-type connecting elbow (22) is 135°; the first-type connecting elbow (21) and the second-type connecting elbow (22) are arranged alternately in sequence; and both ends of the first-type connecting elbow (21) and the second-type connecting elbow (22) are connected to a conveying pipeline (1).

5. The long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system according to claim 4 is characterized in that: The second type of connecting elbow (22) is connected to a boosting pipeline (3), and each boosting pipeline (3) is connected to an air compressor (5). The multiple boosting pipelines (3) and the multiple air compressors (5) form a multi-stage boosting delivery mode and increase the number of propulsion stages according to the length of the delivery distance.

6. The long-distance multi-stage pressurized pneumatic conveying anti-erosion pipeline system according to claim 4 is characterized in that: The concave sides of the first-type connecting elbow (21) and the second-type connecting elbow (22) are both provided with a partially thickened and deformed bowl-shaped structure (23).

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