Iron tailings paste backfill concentration-flow rate dual closed-loop intelligent control method

Abstract

This invention belongs to the field of industrial automation technology. It discloses a dual closed-loop intelligent control method for iron tailings paste filling concentration and flow rate, comprising: determining benchmark resistance characteristic parameters based on pipeline parameters and paste properties, and setting target ranges for concentration and flow rate; collecting real-time concentration and flow rate values, comparing them with the target ranges to determine the coupling interference level; selecting master and slave control parameters based on the coupling interference level, determining the control priority and timing, and generating coordinated control commands; inputting the commands into the concentration and flow rate closed-loop control channel for control, setting interlock protection limits for simultaneous large-scale adjustment; monitoring pipeline pressure and end-point flow rate, switching to emergency dredging mode in case of abnormalities, and entering a new control cycle after recovery; ensuring the continuous and stable operation of the filling system.

Description

Technical Field

[0001] This invention relates to the field of industrial automation technology, and more specifically, to a dual closed-loop intelligent control method for iron tailings paste filling concentration and flow rate. Background Technology

[0002] Existing paste filling control technologies are insufficient in achieving dynamic coordinated regulation of concentration and flow rate, a problem particularly pronounced in long-distance pipeline transportation and under varying operating conditions. Specifically, iron tailings paste, as a typical non-Newtonian fluid, exhibits significantly nonlinear rheological characteristics with concentration variations. When the filling concentration is adjusted, the yield stress and plastic viscosity of the paste change accordingly, directly affecting the pipeline's transport resistance characteristics and causing the predetermined flow rate control strategy to fail. Simultaneously, when the flow rate changes, the shear state of the paste within the pipeline also changes, which in turn interferes with the stability and accuracy of concentration detection, thus forming a complex two-way dynamic coupling relationship between concentration and flow rate. The currently widely used single-parameter closed-loop control method can only independently adjust one parameter, either concentration or flow rate, failing to effectively perceive and decouple the strong correlation between these parameters. When the properties of the filling material fluctuate or the transportation conditions change, the single closed-loop control system often experiences problems such as adjustment oscillation, response lag, and even control instability, increasing the risk of pipeline blockage and causing significant fluctuations in the quality of the filling material, severely hindering the development of paste filling systems towards safety, efficiency, and intelligence.

[0003] In view of this, the present invention proposes a dual closed-loop intelligent control method for iron tailings paste filling concentration and flow rate to solve the above problems. Summary of the Invention

[0004] To overcome the aforementioned deficiencies of the prior art and to achieve the above objectives, the present invention provides the following technical solution: a dual closed-loop intelligent control method for iron tailings paste filling concentration and flow rate, comprising:

[0005] Step S1: Obtain the pipe diameter, pipe length and elevation difference along the pipeline for conveying the paste. Combine the solid density and liquid density of the iron tailings paste to determine the reference resistance characteristic parameters of the pipeline for conveying the paste. In combination with the target stope location of the current filling operation, set the target concentration range and the target flow rate range.

[0006] Step S2: Collect the real-time concentration value and real-time flow rate value of the paste at the pipeline inlet, compare the real-time concentration value with the concentration target range to obtain the concentration deviation status indicator, compare the real-time flow rate value with the flow rate target range to obtain the flow rate deviation status indicator, and determine the current coupling interference level based on the combination relationship of the two types of deviation status indicators.

[0007] Step S3: Select the corresponding master and slave parameters from the preset decoupling control strategy set according to the coupling interference level, determine the control priority of the master parameter and the follow-up response timing of the slave parameter, and generate a coordinated control command sequence.

[0008] Step S4: Input the coordinated adjustment command sequence into the concentration closed-loop control channel and the flow rate closed-loop control channel respectively. The concentration closed-loop control channel drives the feeding device and the dilution water valve group to perform concentration adjustment action, and the flow rate closed-loop control channel drives the filling pump group to perform flow rate adjustment action. Interlock protection conditions are set between the two channels to limit the simultaneous large adjustment.

[0009] Step S5: Continuously monitor the pressure distribution along the pipeline and the end filling flow. When an abnormal pressure rise or flow drop is detected, trigger the pipe blockage signal, suspend the execution of the current regulation command sequence, and switch to the emergency unblocking control mode. After the pipeline status is restored, enter a new round of regulation cycle.

[0010] The technical effects and advantages of the present invention's intelligent control method for iron tailings paste filling concentration and flow rate via a dual closed loop are as follows:

[0011] This invention determines the priority order and follow-up response sequence of the primary and secondary control parameters based on the coupling interference level, ensuring that the control actions follow a primary-secondary timing coordination mechanism. This effectively decouples the interference of concentration changes on flow rate and the reverse influence of flow rate changes on concentration detection, avoiding oscillations and instability caused by simultaneous dual-parameter control. By setting interlock protection conditions between the concentration closed-loop control channel and the flow rate closed-loop control channel, it restricts the simultaneous execution of large-scale control actions by both channels, preventing abnormal increases in pipeline transport resistance caused by drastic changes in the rheological properties of the paste during the control process. By continuously monitoring the pressure distribution along the pipeline and the end-filling flow rate and setting an emergency unblocking control mode, it achieves early warning and rapid handling of pipe blockage risks, ensuring the continuous and stable operation of the filling system, thereby improving the safety of iron tailings paste filling operations and the consistency of filling quality. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the iron tailings paste filling concentration-flow rate dual closed-loop intelligent control method of the present invention. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] Example 1

[0015] Please see Figure 1 As shown in this embodiment, the iron tailings paste filling concentration-flow rate dual closed-loop intelligent control method includes:

[0016] Step S1: Obtain the pipe diameter, pipe length and elevation difference along the pipeline for transporting the paste. Combine the solid and liquid phase densities of the iron tailings paste to determine the baseline resistance characteristic parameters for pipeline transport. Set the target concentration range and flow rate range based on the target stope location of the current backfilling operation.

[0017] The iron tailings paste backfilling system mainly consists of three parts: a preparation station, a conveying pipeline, and a backfilling area in the stope. The preparation station is responsible for mixing iron tailings, cement, and water in a specific ratio to form a paste; the conveying pipeline transports the prepared paste to the underground goaf; and the backfilling area receives the paste and completes the backfilling operation. Before the backfilling operation begins, the system's baseline operating parameters need to be determined based on the pipeline's physical characteristics and the paste's material properties to provide a reference for subsequent dynamic control.

[0018] Iron tailings paste, as a typical Bingham plastic fluid, exhibits flow characteristics fundamentally different from ordinary Newtonian fluids. When the paste flows in a pipeline, it must overcome yield stress to initiate flow, while simultaneously overcoming viscous resistance due to its plastic viscosity. The pipeline's geometric parameters, the paste's physical properties, and the operating conditions collectively determine the system's transport resistance characteristics. Therefore, before starting the control system, it is necessary to comprehensively consider these factors and establish benchmark resistance characteristic parameters that reflect the overall transport difficulty of the pipeline, thereby guiding the reasonable setting of target concentration and flow velocity ranges.

[0019] Preferably, in some possible implementations of the embodiments of the present invention, the specific implementation method of step S1 includes:

[0020] Calculate the gravitational potential energy parameters of the pipeline based on the elevation difference along the pipeline. The calculation formula is: In the formula, This refers to the density of the paste mixture, expressed in kilograms per cubic meter. The acceleration due to gravity is taken as 9.8 meters per second squared. The elevation difference along the pipeline (i.e., the vertical drop between the start and end points of the pipeline) is expressed in meters. Positive values ​​indicate downward transport, while negative values ​​indicate upward transport. Negative values ​​correspond to the upward section that requires additional pumping energy, while positive values ​​correspond to the downward section that can utilize gravitational potential energy.

[0021] It should be noted that the density of the paste mixture is determined by the solid phase density, liquid phase density, and mass concentration, and the calculation formula is as follows: In the formula, The concentration of the paste is dimensionless, and in this embodiment, the value ranges from 0.65 to 0.75. The solid density of iron tailings is taken as 2800 kg / m³ to 3200 kg / m³ in this embodiment, with a typical value of 3000 kg / m³. This embodiment uses the typical value. The value is the density of the liquid phase; in this embodiment, it is taken as the density of water, which is 1000 kg per cubic meter.

[0022] Obtain the rheological parameters of the paste and calculate the initiation resistance and viscous resistance components: Obtain the yield stress of the iron tailings paste at the standard test concentration. With plastic viscosity measurement value The standard test concentration refers to the concentration value used when conducting rheological tests on the paste under laboratory conditions. In this embodiment, the standard test concentration is taken as 70% by mass. Yield stress The value ranges from 50 Pascals to 300 Pascals, and the plastic viscosity is... The value ranges from 0.5 Pascals per second to 2.0 Pascals per second.

[0023] The starting resistance component is obtained by correlating the measured yield stress value with the pipe inner diameter. The calculation formula is: ;in, This refers to the inner diameter of the pipe, in meters. The total length of the pipe is expressed in meters. This formula is derived from the pressure balance equation of Bingham fluid flow in a circular pipe and reflects the minimum resistance that the paste needs to overcome to start flowing from a static state. The starting resistance component is directly proportional to the yield stress and the pipe length, and inversely proportional to the pipe inner diameter. The thinner and longer the pipe, the greater the yield stress of the paste, and the higher the pressure required to start the flow.

[0024] The viscous resistance component is obtained by correlating the measured plastic viscosity value with the pipe inner diameter and the total pipe length. The calculation formula is: In the formula, The design flow rate is expressed in cubic meters per second. In this embodiment... The value is 0.05, and the range is from 0.02 cubic meters per second to 0.1 cubic meters per second; the viscous resistance component reflects the resistance loss caused by internal friction when the paste flows stably in the pipeline.

[0025] By superimposing and integrating the starting resistance component, viscous resistance component, and gravitational potential energy parameter, a benchmark resistance characteristic parameter reflecting the overall transportation difficulty of the pipeline is obtained. The calculation formula is: In the formula, when the pipeline is for downward transport, the gravitational potential energy parameter is... A positive value indicates that it plays an auxiliary role in transportation; when the pipeline is transporting upstream, the gravitational potential energy parameter... A negative value requires additional pumping energy to overcome gravity; subtracting the negative value is equivalent to adding the absolute value. Reference resistance characteristic parameters. The unit is Pascal, and the higher the value, the more difficult the pipeline transportation is.

[0026] Set target concentration and flow rate ranges. Based on the relative depth and horizontal distance of the target stope location within the mine backfill area, retrieve initial concentration and flow rate reference values ​​from a pre-defined operating parameter table. The operating parameter table is a lookup table established based on historical mine backfill data and engineering experience; its structure is shown in the table below.

[0027] Table 1 shows the operating condition parameters (partial):

[0028] Relative depth range (meters) Horizontal distance range (meters) Initial concentration reference value (%) Initial flow velocity reference value (m / s) 0 to 100 0 to 500 72 1.8 0 to 100 500 to 1000 71 2.0 100 to 300 0 to 500 70 1.6 100 to 300 500 to 1000 69 1.8 300 to 500 0 to 500 68 1.5 300 to 500 500 to 1000 67 1.6

[0029] It should be noted that the above operating parameter table is exemplary data, and implementers can adjust it according to specific mine conditions and filling process requirements. The greater the relative depth and the greater the horizontal distance, the greater the pipeline transportation resistance. Therefore, it is necessary to appropriately reduce the concentration reference value to ensure fluidity, while adjusting the flow rate reference value to maintain reasonable transportation efficiency.

[0030] The baseline resistance characteristic parameters are compared with a preset resistance grading threshold. In this embodiment, the resistance grading threshold is set to 1.0 MPa, which is determined based on a combination of the pumping capacity of the mine backfilling system and the pressure-bearing capacity of the pipeline.

[0031] When the baseline resistance characteristic parameter is lower than the resistance grading threshold, it indicates that the pipeline transportation conditions are relatively relaxed and the system has a large adjustment margin. At this time, the initial concentration reference value is used. Expand the preset loose floating range to the upper and lower sides of the center. Forming a concentration target range Based on the initial flow rate reference value Expand the preset loose floating range to the upper and lower sides of the center. Forming the target flow velocity range In this embodiment, the floating range is loose. The value is 2% (absolute concentration). The value is 0.3 meters per second.

[0032] When the baseline resistance characteristic parameter is higher than or equal to the resistance grading threshold, it indicates that the pipeline transportation conditions are relatively tight and the system adjustment margin is limited. At this time, the preset tightening floating range is expanded upward and downward from the initial concentration reference value. A concentration target range is established, and the preset contraction and fluctuation range is expanded upwards and downwards from the initial flow rate reference value. A target flow velocity range is formed. In this embodiment, the floating amplitude is tightened. The value is 1% (absolute concentration). The value is 0.15 meters per second, which is less than the corresponding loose fluctuation range.

[0033] Using the aforementioned tiered setting strategy, when pipeline transport resistance is high, the rheological properties of the paste are more sensitive to changes in concentration and flow rate. Even small parameter fluctuations can lead to drastic changes in transport resistance. Therefore, a narrower target range needs to be set to constrain parameter fluctuations and reduce the risk of pipe blockage. When pipeline transport resistance is low, the system has a higher tolerance for parameter fluctuations, allowing for a wider target range to be set, providing greater operational flexibility for subsequent adjustments. This adaptive range setting method effectively balances safety and flexibility.

[0034] Step S2: Collect the real-time concentration value and real-time flow rate value of the paste at the pipeline inlet, compare the real-time concentration value with the concentration target range to obtain the concentration deviation status indicator, compare the real-time flow rate value with the flow rate target range to obtain the flow rate deviation status indicator, and determine the current coupling interference level based on the combination relationship of the two types of deviation status indicators.

[0035] During the paste filling process, the actual concentration and flow rate at the pipeline inlet will deviate from the target range due to factors such as fluctuations in raw material properties, changes in equipment operating status, and alterations in pipeline conditions. Existing single-parameter closed-loop control methods can only independently adjust one parameter, either concentration or flow rate, ignoring the coupling relationship between the two parameters. In reality, iron tailings paste, as a non-Newtonian fluid, exhibits significantly nonlinear rheological characteristics with varying concentrations: as the concentration increases, both yield stress and plastic viscosity increase, leading to increased pipeline transport resistance and a natural decrease in flow rate with constant pumping power; conversely, as the concentration decreases, the flow rate naturally increases. This bidirectional dynamic coupling between concentration and flow rate means that adjusting one parameter alone often triggers a chain reaction of changes in the other parameter, potentially leading to oscillations or control instability.

[0036] Therefore, the real-time parameter values ​​are first collected and the deviation status is determined. Then, the current coupling interference level is determined based on the combination relationship between the two types of deviation status, which provides a basis for selecting a suitable decoupling adjustment strategy.

[0037] Specifically, real-time concentration and flow rate values ​​are collected. Concentration and flow rate detection devices are installed at the pipeline inlet. In this embodiment, a nuclear density meter is used for concentration detection. Its working principle is to calculate the density of the paste by utilizing the attenuation of gamma rays passing through it, and then converting this density to the density of the solid-liquid two-phase mixture to obtain the mass concentration. In this embodiment, an electromagnetic flow meter is used for flow rate detection. Its working principle is to measure the flow rate by utilizing the induced electromotive force generated when a conductive fluid cuts magnetic lines of force. Both detection devices feature fast response speed, high measurement accuracy, and suitability for slurries containing solid particles.

[0038] The sampling frequency of the concentration detection device is set to 1 Hz, meaning that concentration data is collected once per second; the sampling frequency of the flow rate detection device is also set to 1 Hz. The collected raw data is processed by median filtering and output as real-time concentration and flow rate values. The median filter window length is set to 5, meaning that the median of the five most recent samples is used as the output to eliminate the influence of measurement noise and transient interference.

[0039] Determine the concentration deviation status indicator and the flow rate deviation status indicator: [This refers to] the real-time concentration value. Concentration target range Compare: When When the concentration deviation is high, the status is marked as "concentration too high"; when... When the concentration deviation is normal, the status is marked as "moderate concentration"; when... When the concentration deviation is detected, the status is marked as "concentration too low".

[0040] Real-time flow rate value and the target flow velocity range Compare: When When the flow rate deviation is detected, the status is marked as "flow rate is too fast"; when... When the flow rate deviation is normal, the flow rate deviation status is marked as "moderate flow rate"; when... When the flow rate deviation is detected, the status is marked as "flow rate is too slow".

[0041] Simultaneously calculate the concentration deviation amplitude. and flow velocity deviation amplitude :

[0042] ; ;

[0043] The deviation amplitude is a non-negative value used to quantify the degree to which the parameter deviates from the target range, providing a basis for subsequently determining the master and slave parameters.

[0044] Determine the current level of coupling interference and establish a nine-square grid combination matrix of concentration deviation status indicators and flow velocity deviation status indicators;

[0045] Table 2 shows the combination matrix as follows:

[0046] type The flow rate is too fast Moderate flow rate Slow flow rate High concentration Weak coupling (concentration-dominated) Weak coupling Strong coupling (concentration-driven) moderate concentration Weak coupling Uncoupled Weak coupling low concentration Strong coupling (flow rate dominant) Weak coupling Weak coupling (flow rate dominant)

[0047] The combination of moderate concentration and moderate flow rate is marked as the level of no coupling interference. At this time, both parameters are within the target range, the system is operating normally, and no adjustment is required.

[0048] A combination of concentration deviation and flow rate deviation exhibiting a unidirectional deviation is categorized as a weak coupling interference level. Unidirectional deviation refers to either a high concentration and a fast flow rate, or a low concentration and a slow flow rate. These two scenarios conform to the general rheological characteristics of pastes: decreasing concentration leads to a decrease in viscosity, resulting in a faster flow rate at the same pumping pressure; increasing concentration leads to an increase in viscosity, resulting in a slower flow rate. Unidirectional deviation indicates that the system's coupling relationship is as expected and can be corrected through a relatively simple single-parameter priority adjustment strategy.

[0049] A combination of inverse deviations between concentration and flow rate is categorized as a strong coupling interference level. Inverse deviation refers to either a high concentration and a slow flow rate, or a low concentration and a fast flow rate. These two scenarios indicate that the system has been subjected to external interference exceeding the normal coupling relationship. Examples include partial pipe blockage leading to high concentration and low flow rate, or an abnormal increase in pump power leading to low concentration and high flow rate. Under strong coupling, the deviations of the two parameters are mutually restrictive; simple single-parameter adjustments may further worsen the other parameter, thus requiring more complex decoupling control strategies.

[0050] For strong coupling interference levels, further subdivisions are made based on the deviation magnitude comparison results into concentration-dominant and flow rate-dominant types. When the concentration deviation magnitude is greater than the flow rate deviation magnitude, it is determined to be a concentration-dominant type; otherwise, it is determined to be a flow rate-dominant type.

[0051] By determining the coupling interference level as described above, the system can quantitatively perceive the coupling state of the current concentration-flow rate dual parameters, laying the foundation for selecting targeted decoupling control strategies. This state-combination-based hierarchical determination method can effectively distinguish between normal operating condition fluctuations and abnormal coupling interference, avoiding over-adjustment or under-adjustment problems caused by applying a uniform control strategy to all deviation states.

[0052] Step S3: Select the corresponding master and slave parameters from the preset decoupling control strategy set according to the coupling interference level, determine the control priority of the master parameter and the follow-up response timing of the slave parameter, and generate a coordinated control command sequence.

[0053] Existing paste filling control systems typically employ independent control of concentration and flow rate. Each control loop adjusts its own PID control based on the deviation between the setpoint and the measured value, lacking a coordination mechanism. This control method works normally with small deviations in a single parameter, but when both parameters deviate simultaneously and are coupled, the two control loops may produce conflicting adjustment actions, leading to system oscillations or even instability.

[0054] Based on the aforementioned determined coupling interference level, a corresponding regulation strategy is selected from a preset decoupling regulation strategy set. The division of labor between the master and slave parameters is clarified, a master-slave time-series regulation mechanism is established, and a coordinated regulation command sequence is generated. This coordinated regulation mechanism can effectively decouple the strong correlation between concentration and flow rate, avoiding oscillations and instability caused by simultaneous regulation of two parameters.

[0055] When the coupling interference level is at the no-coupling interference level, both the concentration and flow rate are within the target range, and the system operates normally. At this time, no master or slave parameters are set, and the current concentration and flow rate setpoints are maintained unchanged. The subsequent instruction generation steps are skipped, and the system directly enters the status monitoring stage in step S5.

[0056] When the coupling interference level is weak, the parameter with the larger deviation amplitude is set as the master parameter, and the parameter with the smaller deviation amplitude is set as the slave parameter. The specific determination method is as follows: If... Then concentration is the primary control parameter and flow rate is the secondary control parameter; if In this case, the flow rate is the primary control parameter and the concentration is the secondary control parameter.

[0057] In the weakly coupled state, the adjustment range of the tuning parameter follows the preset proportional coefficient. Reduction, in this embodiment The value is set to 0.5, with a range of 0.3 to 0.7. This means that the adjustment of the slave parameter is only half that of the master parameter, to avoid over-adjustment leading to parameter overshoot. The basis for setting the follower proportional coefficient is that, in a weakly coupled state, the deviation directions of the two parameters are consistent, and adjusting the master parameter will naturally drive the slave parameter to change in the correct direction. Therefore, the slave parameter only needs auxiliary adjustment.

[0058] When the coupling interference level is strong and concentration is dominant, concentration is set as the primary control parameter and flow rate as the secondary control parameter. In a strong coupling state, the secondary control parameter needs to delay for a preset response interval after the primary control parameter completes a single-step adjustment before initiating further adjustment. In this embodiment, the response interval is between 5 and 15 seconds, with a typical value of 10 seconds; this embodiment uses the typical value. The response interval is set based on the fact that in a strong coupling state, the two parameters deviate in opposite directions. It is necessary to wait for the adjustment effect of the primary control parameter to propagate and stabilize in the system before determining the adjustment direction and magnitude of the secondary control parameter based on the new parameter state, in order to avoid adjustment conflicts.

[0059] When the coupling interference level is strong and the flow rate is dominant, set the flow rate as the primary control parameter and the concentration as the secondary control parameter, with the same adjustment timing rules as above; determine the adjustment direction based on the deviation direction of the primary control parameter: if the primary control parameter is too high (high concentration or fast flow rate), the adjustment direction is to decrease; if the primary control parameter is too low (low concentration or slow flow rate), the adjustment direction is to increase.

[0060] The adjustment direction is determined by the following relationship of the master parameter: either following in the same direction or compensating in the opposite direction. In the weak coupling state, the following in the same direction strategy is adopted, that is, the adjustment direction of the master parameter is consistent with that of the master parameter. In the strong coupling state, the opposite compensation strategy is adopted, that is, the adjustment direction of the master parameter is opposite to that of the master parameter, in order to compensate for the coupling effect.

[0061] In a strongly coupled state, the reverse compensation strategy means that adjusting the master parameter will have an opposite effect on the slave parameter through the coupling relationship. For example, when the concentration is high and the flow rate is slow (strong coupling, concentration-dominant), reducing the concentration will lead to a decrease in viscosity, and the flow rate will naturally increase. However, the original deviation of the slave parameter (flow rate) is towards slowness, so the flow rate needs to be adjusted in the direction of increase to compensate for the original deviation. The reverse compensation strategy can correct the deviations of both parameters simultaneously, rather than relying on the collateral effect of adjusting the master parameter.

[0062] A coordinated adjustment command sequence is generated, and the corresponding single-step adjustment amount is retrieved from a preset adjustment step size table based on the current deviation of the main adjustment parameter. The structure of the adjustment step size table is shown in the table below:

[0063] Table 3, the adjustment step size table (concentration parameter), is as follows:

[0064] Deviation range (%) Single-step adjustment amount (%) 0 to 0.5 0.2 0.5 to 1.0 0.4 Versions 1.0 to 2.0 0.6 Greater than 2.0 0.8

[0065] Table 4, the adjustment step size table (flow rate parameters), is as follows:

[0066] Deviation range (m / s) Single-step adjustment amount (m / s) 0 to 0.1 0.05 0.1 to 0.2 0.08 0.2 to 0.3 0.12 Greater than 0.3 0.15

[0067] The adjustment step size table is designed according to the principle of "small step size for small deviation, large step size for large deviation," but there is an upper limit to the single-step adjustment to avoid over-adjustment. The larger the deviation, the larger the single-step adjustment, which can speed up the correction speed; however, the single-step adjustment will not increase indefinitely to prevent system overshoot.

[0068] The single-step adjustment amount of the master mode is calculated based on the follow-up proportional coefficient of the master mode parameter: the single-step adjustment amount of the master mode is the ratio of the single-step adjustment amount of the master mode to the follow-up proportional coefficient.

[0069] The timestamp of the main control instruction is determined based on the adjustment priority of the main control parameters. The timestamp of the slave command is determined based on the current system time and the follow-up response timing of the slave parameters. :

[0070] In a weakly coupled state: ,in The basic timing interval is set to 2 seconds in this embodiment;

[0071] Under strong coupling conditions: ,in The response interval is set to 10 seconds in this embodiment.

[0072] The main control command encapsulates the main control single-step adjustment amount, main control adjustment direction, and main control command timestamp into a main control command; the slave control command encapsulates the slave control single-step adjustment amount, slave control adjustment direction, and slave control command timestamp into a slave control command. The main control command and slave control command are arranged in chronological order according to their timestamps to form a coordinated control command sequence.

[0073] Through the aforementioned mechanism for generating coordinated control command sequences, the system can schedule the adjustment actions of concentration and flow rate in a timely manner, ensuring that the adjustment of the primary control parameter is executed first, followed by the adjustment of the secondary control parameter, thus avoiding conflicting control commands issued by the two control channels simultaneously. This master-secondary timing coordination mechanism is a key technical means to achieve decoupled concentration-flow rate control.

[0074] Step S4: Input the coordinated adjustment command sequence into the concentration closed-loop control channel and the flow rate closed-loop control channel respectively. The concentration closed-loop control channel drives the feeding device and the dilution water valve group to perform concentration adjustment action, and the flow rate closed-loop control channel drives the filling pump group to perform flow rate adjustment action. Interlock protection conditions are set between the two channels to limit the simultaneous large adjustment.

[0075] This step is the execution stage of the entire control method. It is responsible for converting the coordinated control command sequence into specific equipment control actions. The concentration closed-loop control channel and the flow rate closed-loop control channel manage their respective actuators, but the two channels are coordinated through an interlock protection mechanism to prevent system instability caused by simultaneous large adjustments.

[0076] The concentration closed-loop control channel extracts control commands for the concentration parameter from the coordinated regulation command sequence, and analyzes them to obtain the concentration regulation direction and single-step concentration regulation amount. The concentration of the paste is adjusted by two actuators working together: a feeding device and a dilution water valve group. The feeding device is responsible for feeding dry iron tailings into the mixing tank. In this embodiment, a screw feeder is used, and its feeding rate is controlled by adjusting the screw speed. The dilution water valve group is responsible for injecting water into the mixing tank, and the water injection flow rate is controlled by adjusting the valve opening.

[0077] When the concentration adjustment direction is to increase, the solid-liquid ratio needs to be increased. The specific actions are as follows: send an acceleration command to the feeding device to increase the feeding rate of dry iron tailings; at the same time, send a flow reduction command to the dilution water valve group to reduce the injection flow rate of dilution water.

[0078] When the concentration adjustment direction is to decrease, the solid-liquid ratio needs to be reduced. The specific actions are as follows: send a deceleration command to the feeding device to reduce the feeding rate of dry iron tailings; at the same time, send a flow increase command to the dilution water valve group to increase the injection flow rate of dilution water.

[0079] Adjust the amount of concentration step by step Calculate the change in rotational speed of the feeding device Changes in the opening degree of the dilution water valve assembly The conversion relationship is established based on the material balance equation:

[0080] Assume the current rotation speed of the feeding device is (Revolutions / minute), the corresponding dry material feeding rate is (kg / min); Assume the current opening degree of the dilution water valve group is... (%), corresponding to the water injection flow rate is (liters / minute); assuming the total volume of paste in the mixing jar is... (kg), current concentration is (%).

[0081] To make the concentration change Required increase in dry matter and water increment satisfy:

[0082] ;

[0083] After simplification, we get: ; ;

[0084] Convert the increase in dry material and the increase in water into changes in rotational speed and changes in opening: ; In the formula, This is the conversion factor between the rotational speed of the feeding device and the feeding rate, expressed in kilograms per revolution. In this embodiment, the value is 0.1 kilograms per revolution. The opening degree to flow rate conversion factor for the dilution water valve assembly is expressed in liters per percentage point per minute (L / min). In this embodiment, the value is 0.5 L / min. To adjust the time step, this embodiment uses a value of 60 seconds. ρ is the density of the liquid phase.

[0085] The conversion result is appended as an execution parameter to the corresponding instruction and sent to the actuator. After the instruction is issued, a concentration response timer is started, and the timer waits for a preset concentration response duration. Then, new real-time concentration values ​​are collected to verify whether the adjustment action has taken effect. In this embodiment... The value ranges from 60 seconds to 120 seconds, with a typical value of 90 seconds. This embodiment uses the typical value. The concentration response waiting time is from the adjustment action of the feeding device and dilution water valve group to the flow of the adjusted paste through the mixing tank and transmission pipeline and finally to the concentration detection point at the pipeline inlet. There is a certain time delay, which depends on factors such as the volume of the mixing tank, the preparation flow rate, and the pipeline length.

[0086] The verification method is to compare the newly collected real-time concentration value with the concentration value before adjustment: if the direction of concentration change is consistent with the direction of adjustment and the change amplitude reaches more than 50% of the single-step adjustment amount, the adjustment action is determined to be effective; if the direction of concentration change is opposite to the direction of adjustment or the change amplitude is less than 30% of the single-step adjustment amount, the adjustment action is determined to be ineffective and an abnormal alarm is triggered; if the change amplitude is between 30% and 50%, the adjustment action is determined to be partially effective, and the single-step adjustment amount is increased in the next round of adjustment.

[0087] The flow velocity closed-loop control channel executes flow velocity regulation actions. It extracts control commands for flow velocity parameters from the coordinated regulation command sequence and parses them to obtain the flow velocity regulation direction and single-step flow velocity regulation amount. The flow rate of the paste is adjusted by a filling pump unit. In this embodiment, the filling pump unit uses variable frequency plunger pumps, with a total of 3 pumps configured, including 2 main operating pumps and 1 standby pump. The rated displacement of each pump ranges from 0.01 cubic meters per second to 0.05 cubic meters per second, and the displacement can be continuously adjusted through frequency conversion. The flow rate is determined based on the current number of operating filling pumps. and the rated displacement range of a single pump Determine the single-step adjustment amount of the flow rate. Does this exceed the adjustment margin provided by the current number of operating units? The adjustment margin is calculated as follows: Let the pipe cross-sectional area be... The total displacement of the currently operating pumps is The current flow rate If the flow rate adjustment direction is to increase, then the adjustment margin is... If the flow rate adjustment direction is decreasing, then the adjustment margin is... Convert the single-step flow rate adjustment to the displacement adjustment. ;Compare and When the single-step flow rate adjustment amount does not exceed the adjustment margin (i.e. When this occurs, only the displacement setting of the currently operating pump is adjusted, and a displacement change command is sent to all operating pumps. The displacement change is evenly distributed among all operating pumps, with the displacement change for each pump being [missing value]. .

[0088] When the single-step flow rate adjustment exceeds the adjustment margin and the flow rate adjustment direction is increasing, it indicates that the currently operating pump set cannot provide sufficient incremental discharge, and the standby pump needs to be started to join the operation. The specific operation is as follows:

[0089] 1. Send a grid connection and commissioning command to the standby pump to start the standby pump;

[0090] 2. Wait for the standby pump to start up and reach the minimum stable discharge rate (approximately 30 to 60 seconds);

[0091] 3. The displacement increment will be redistributed among all operating pumps (including newly started pumps).

[0092] When the single-step flow rate adjustment exceeds the adjustment margin and the flow rate adjustment direction is decreasing, it indicates that the currently operating pump set needs to reduce its discharge beyond its adjustment range. It is advisable to consider shutting down some pumps to improve the operating efficiency of the remaining pumps. The specific operation is as follows:

[0093] 1. Compare the current displacement of each operating pump and select the pump with the lowest displacement as the one to be cut off;

[0094] 2. Gradually reduce the pump's displacement to a minimum, while simultaneously transferring its displacement to other operating pumps;

[0095] 3. Send a stop and exit command to the selected pump to remove it from operation.

[0096] After the pump set adjustment command is issued, the flow rate response timer is started. After the timer reaches the preset flow rate response waiting time, a new real-time flow rate value is collected, and the effectiveness of the adjustment action is verified. In this embodiment, the preset flow rate response waiting time is between 10 and 30 seconds, with a typical value of 15 seconds. This embodiment uses the typical value. The basis for setting the flow rate response waiting time is that the discharge adjustment response time of the filling pump set is relatively fast, but it is necessary to wait for the fluid in the pipeline to establish a new steady-state flow. This time is related to the pipeline length and flow rate.

[0097] To prevent system instability caused by simultaneous large adjustments in the concentration and flow rate channels, an interlock protection condition is set between the two channels.

[0098] Define the threshold for large adjustment of the concentration channel And the threshold for large-scale adjustment of flow rate channels In this embodiment The value is 0.5% (absolute concentration). The value is set to 0.1 meters per second. When the single-step adjustment exceeds the above threshold, the adjustment action will have a significant impact on the rheological properties of the paste, and may cause drastic changes in the coupling effect.

[0099] When the single-step adjustment of any channel exceeds its corresponding large-scale adjustment threshold, the channel is determined to be in a large-scale adjustment state. The interlock determination logic is as follows:

[0100] Interlock protection is triggered when both the concentration channel and the flow rate channel are simultaneously under significant adjustment. The interlock protection is executed as follows:

[0101] 1. Pause the execution of adjustment commands from the channel containing the adjustment parameters;

[0102] 2. Only the channel containing the primary parameter is allowed to complete the current adjustment action;

[0103] 3. After the current adjustment action is completed in the channel where the main adjustment parameter is located and after the preset interlock release waiting time, release the pause lock on the channel where the slave adjustment parameter is located;

[0104] 4. Allow the execution of paused adjustment commands to continue from the channel where the adjustment parameters are located.

[0105] In this embodiment, the preset interlock release waiting time ranges from 15 seconds to 30 seconds, and in this embodiment, it is set to 20 seconds. The basis for setting this time is that it is necessary to wait for the adjustment effect of the master parameter to stabilize in the system before performing the adjustment of the slave parameter, so as to avoid the adjustment effects of the two from superimposing and causing an overreaction.

[0106] During the interlock protection triggering period, the pipeline inlet pressure is continuously monitored. If abnormal fluctuations occur in the inlet pressure (pressure change rate exceeds the preset pressure fluctuation threshold, which is 0.1 MPa / s in this embodiment), the interlock release waiting time is extended until the pressure returns to stability. Abnormal pressure fluctuations indicate that the system has not yet reached a steady state, and releasing the interlock at this time may exacerbate system oscillations. The interlock protection mechanism prevents simultaneous large adjustments in both control channels from causing drastic changes in the rheological properties of the paste, avoiding the risk of pipe blockage or pump overload caused by a sharp increase in pipeline transport resistance, and ensuring the stable operation of the filling system.

[0107] Step S5: Continuously monitor the pressure distribution along the pipeline and the end filling flow. When an abnormal pressure rise or flow drop is detected, trigger the pipe blockage signal, suspend the execution of the current regulation command sequence, and switch to the emergency unblocking control mode. After the pipeline status is restored, re-enter step S2 and enter a new round of regulation cycle.

[0108] During paste filling operations, pipeline blockage is a major risk threatening the safe operation of the system. Blockage can be caused by a variety of factors: excessively high paste concentration leading to insufficient fluidity, excessively low flow rate causing solid particle deposition, material accumulation at pipe bends, or scaling on the inner wall of the pipe. Once blockage occurs, the pipeline pressure will rise sharply, potentially leading to pipe rupture or pump damage in severe cases. Therefore, this step achieves early warning and rapid handling of blockage risks by continuously monitoring the pressure distribution along the pipeline and the end-filling flow rate.

[0109] To monitor the pressure distribution along the pipeline, pressure sensors are deployed at multiple key locations along the pipeline. The selection criteria for these key locations are as follows:

[0110] 1. Pipeline inlet: Monitor pump unit outlet pressure;

[0111] 2. A monitoring point is set up every 300 to 500 meters along the pipeline to monitor pressure changes along the pipeline;

[0112] 3. Before and after pipe bends, diameter changes, and other local resistance components: these locations are high-risk areas for blockages;

[0113] 4. Before filling the borehole inlet at the end of the pipeline: Monitor the pressure at the end of the pipeline.

[0114] In this embodiment, it is assumed that the total length of the pipeline is 1500 meters, and a total of 5 pressure monitoring points are set: inlet (0 meters), 300 meters, 600 meters, 900 meters, and end (1500 meters). The pressure sensor adopts a diaphragm pressure transmitter with a range of 0 to 5 MPa and an accuracy of ±0.1% of full scale.

[0115] The system collects pressure readings from each sensor in real time, calculates the pressure difference between adjacent sensors, and compares the pressure difference values ​​of each section with the theoretical pressure drop values ​​for that section of the pipeline under the current concentration and flow rate conditions. The theoretical pressure drop value is calculated based on Bingham's pressure loss formula for pipeline flow. In the formula, This is the length of the pipeline section; Current flow rate; and To correspond to the yield stress and plastic viscosity values ​​at the current concentration, The inner diameter of the pipe. This is the theoretical pressure drop value.

[0116] When the measured pressure difference exceeds the preset deviation multiple of the theoretical pressure drop value At that time, it was determined that there were signs of partial blockage in that section of the pipeline. In this embodiment... The value is set to 1.5, meaning an early warning is triggered when the measured pressure difference exceeds 1.5 times the theoretical value. The basis for setting the deviation multiple is: under normal operating conditions, the deviation between the measured pressure difference and the theoretical value generally does not exceed 20%. When the deviation reaches 50%, it indicates that the internal flow state of the pipeline has changed significantly, and there is a risk of blockage.

[0117] To monitor the flow rate at the end of the pipeline, flow sensors are installed at the inlet of the filling borehole. In this embodiment, an ultrasonic flow meter is used. Its working principle is to measure the flow velocity by utilizing the time difference of ultrasonic waves propagating in the fluid, and then converting it into flow rate by combining the cross-sectional area of ​​the pipeline. The advantage of ultrasonic flow meters is that they are non-contact measurements and do not cause additional pressure loss, making them suitable for measuring the flow rate of slurries containing solid particles.

[0118] Real-time acquisition of end-filling flow rate Compare it with the theoretical flow rate corresponding to the lower limit of the target flow rate range. Comparison: In the formula, This represents the lower limit of the target flow velocity range. This represents the cross-sectional area of ​​the pipe.

[0119] When the end-fill flow rate value Continuously below theoretical flow When the preset duration of low flow rate is reached, an abnormal decrease in flow rate is determined. The duration of low flow rate is between 30 and 60 seconds; in this embodiment, it is set to 45 seconds. Instantaneous flow rate fluctuations may be caused by measurement noise or normal system adjustments; only a sustained low flow rate indicates a system anomaly.

[0120] Based on the combined results of localized blockage symptoms and abnormal flow rate decline: a pipe blockage warning signal is generated when either of the two conditions is met; a pipe blockage emergency signal is generated when both conditions are met simultaneously. The pipe blockage warning signal indicates a potential blockage in the system but that it has not yet developed into a complete blockage, requiring preventative measures. The pipe blockage emergency signal indicates that a serious blockage has occurred or is about to occur in the pipeline, necessitating immediate emergency measures.

[0121] In response to a pipe blockage signal, the system switches to emergency unblocking control mode. When a pipe blockage warning signal or an emergency pipe blockage signal is received, the system performs the following operations:

[0122] 1. Lock the execution status of the current coordinated control command sequence and immediately stop sending new control commands to the feeding device, dilution water valve group, and filling pump group. Commands that have been issued but not yet completed will continue to be executed until completion, but no further commands will be issued. The purpose of this operation is to prevent normal control actions from conflicting with emergency dredging actions.

[0123] 2. Reduce the pump set operating frequency and increase the dilution water flow rate. Send a frequency reduction operation command to the filling pump set to reduce the pump set operating frequency to the preset dredging mode operating frequency. In this embodiment, the dredging mode operating frequency is 50% to 70% of the normal operating frequency, with a typical value of 60%. The purpose of reducing the operating frequency is to reduce the flow velocity of the paste in the pipeline, reduce the pipeline pressure, and create conditions for subsequent dilution and dredging.

[0124] Simultaneously, a full-open command is sent to the dilution water valve assembly, setting the valve opening to 100% and injecting dilution water into the pipeline at maximum flow rate. The injection of a large amount of dilution water quickly reduces the concentration and viscosity of the paste within the pipeline, restoring its fluidity and promoting the flushing and removal of blockages.

[0125] 3. Continuously monitor the pipeline status and determine the dredging effect. During the process of frequency reduction operation and dilution water injection, continuously monitor the pipeline inlet pressure and end-filling flow rate. The criteria for determining whether dredging is complete are:

[0126] The inlet pressure drops back to the normal range, which in this embodiment is defined as 80% to 120% of the normal operating pressure.

[0127] End-fill flow rate restored to theoretical flow rate preset recovery ratio The above describes the embodiments of this invention. The value is 0.8.

[0128] When both of the above conditions are met, the pipe dredging is considered complete. If the dredging is not completed within the preset maximum dredging time (10 minutes in this embodiment), a dredging failure alarm is generated, requiring manual intervention.

[0129] 4. Restore normal operation. After the pipeline dredging is completed, the system will gradually return to normal operation:

[0130] A frequency recovery command is sent to the filling pump unit to gradually restore the pump unit's operating frequency from the unblocking mode frequency to the normal operating frequency. The recovery process employs a stepped frequency increase strategy, with each increase being 10% of the normal frequency. After each increase, a 10-second wait is made to observe the system response, and the next increase is only performed after confirmation of stability. A flow rate correction command is sent to the dilution water valve unit to gradually reduce the dilution water flow rate from 100% opening to the normal injection volume. The correction process also employs a stepped strategy, reducing the opening by 20% each time, with a 15-second wait after each reduction to observe the concentration change.

[0131] After the pump frequency and dilution water flow rate return to normal, the command execution lock is released, the paused coordinated regulation command sequence is cleared, the real-time concentration value and real-time flow rate value are collected again, and the process returns to step S2 to enter a new round of regulation cycle.

[0132] Through the aforementioned emergency unblocking control mode, the system can respond quickly upon detecting a blockage risk. By combining measures such as reducing pump frequency and increasing dilution water flow, it clears the pipeline, preventing further blockage from causing equipment damage and production interruptions. This automated emergency response mechanism significantly improves the safety and reliability of the paste filling system.

[0133] The present invention proposes a dual closed-loop intelligent control method for iron tailings paste filling concentration and flow rate. This method systematically solves the technical problem that existing single closed-loop control methods cannot effectively cope with the two-way dynamic coupling relationship between concentration and flow rate by establishing a benchmark resistance characteristic parameter and an adaptive target range setting mechanism, constructing a dual-parameter coupling interference level judgment system, designing a master-follower collaborative adjustment command generation strategy, implementing dual-channel interlock protection control for concentration and flow rate, and configuring pipeline status monitoring and emergency dredging response mechanisms.

[0134] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A double closed loop intelligent control method for tailings paste filling concentration and flow rate, characterized in that, include: Step S1: Obtain the pipe diameter, pipe length and elevation difference along the pipeline for conveying the paste. Combine the solid density and liquid density of the iron tailings paste to determine the reference resistance characteristic parameters of the pipeline for conveying the paste. In combination with the target stope location of the current filling operation, set the target concentration range and the target flow rate range. Step S2: Collect the real-time concentration value and real-time flow rate value of the paste at the pipeline inlet, compare the real-time concentration value with the concentration target range to obtain the concentration deviation status indicator, compare the real-time flow rate value with the flow rate target range to obtain the flow rate deviation status indicator, and determine the current coupling interference level based on the combination relationship of the two types of deviation status indicators. Step S3: Select the corresponding master and slave parameters from the preset decoupling adjustment strategy set according to the coupling interference level, including: when the coupling interference level is no coupling interference level, do not set master and slave parameters, and maintain the current concentration setpoint and flow rate setpoint unchanged; when the coupling interference level is weak coupling interference level, set the parameter with larger deviation as the master parameter and the parameter with smaller deviation as the slave parameter, and reduce the adjustment range of the slave parameter according to the preset following ratio coefficient; when the coupling interference level is strong coupling interference level and belongs to the concentration-dominated type, set the concentration as the master parameter and the flow rate as the slave parameter, and delay the adjustment of the slave parameter by a preset response interval time after the master parameter completes the single-step adjustment; when the coupling interference level is strong coupling interference level and belongs to the flow rate-dominated type, set the flow rate as the master parameter and the concentration as the slave parameter; according to the deviation of the master parameter... The direction of adjustment is determined by the difference direction, whether it is increasing or decreasing. The direction of adjustment is determined by the following relationship of the slave parameter, whether it is following in the same direction or compensating in the opposite direction. The adjustment priority of the master parameter and the following response timing of the slave parameter are determined to generate a coordinated adjustment command sequence, including: retrieving the corresponding master single-step adjustment amount from a preset adjustment step size table based on the current deviation of the master parameter; calculating the slave single-step adjustment amount based on the following proportional coefficient of the slave parameter; determining the timestamp of the master command based on the adjustment priority of the master parameter; determining the timestamp of the slave command based on the following response timing of the slave parameter, with the timestamp of the slave command being later than the timestamp of the master command; encapsulating the master single-step adjustment amount and the timestamp of the master command into a master control command, and encapsulating the slave single-step adjustment amount and the timestamp of the slave command into a slave control command; arranging the master control command and slave control command in chronological order according to their timestamps to form a coordinated adjustment command sequence. Step S4: Input the coordinated adjustment command sequence into the concentration closed-loop control channel and the flow rate closed-loop control channel respectively. The concentration closed-loop control channel drives the feeding device and the dilution water valve group to perform concentration adjustment action, and the flow rate closed-loop control channel drives the filling pump group to perform flow rate adjustment action. Interlock protection conditions are set between the two channels to limit the simultaneous large adjustment. Step S5: Continuously monitor the pressure distribution along the pipeline and the end filling flow. When an abnormal pressure rise or flow drop is detected, trigger the pipe blockage signal, suspend the execution of the current regulation command sequence, and switch to the emergency unblocking control mode. After the pipeline status is restored, enter a new round of regulation cycle.

2. The intelligent control method for iron tailings paste filling concentration-flow rate with a dual closed loop according to claim 1, characterized in that, Step S1 includes: The gravitational potential energy parameters of the pipeline are calculated based on the elevation difference along the pipeline; the yield stress and plastic viscosity of the iron tailings paste at the standard test concentration are obtained; the yield stress is correlated with the pipeline inner diameter to obtain the starting resistance component; and the plastic viscosity is correlated with the pipeline inner diameter and the total pipeline length to obtain the viscous resistance component. The starting resistance component, viscous resistance component, and gravitational potential energy parameter are superimposed and integrated to obtain the baseline resistance characteristic parameters; based on the relative depth and horizontal distance of the target stope location in the mine filling area, the initial concentration reference value and initial flow velocity reference value are retrieved from the preset working condition parameter table. The baseline resistance characteristic parameter is compared with the preset resistance grading threshold. When the baseline resistance characteristic parameter is lower than the resistance grading threshold, a preset loose floating range is expanded upwards and downwards from the initial concentration reference value to form a concentration target range, and a preset loose floating range is expanded upwards and downwards from the initial flow velocity reference value to form a flow velocity target range. When the baseline resistance characteristic parameter is higher than or equal to the resistance grading threshold, a preset tight floating range is expanded upwards and downwards from the initial concentration reference value to form a concentration target range, and a preset tight floating range is expanded upwards and downwards from the initial flow velocity reference value to form a flow velocity target range, wherein the tight floating range is smaller than the loose floating range.

3. The intelligent control method for iron tailings paste filling concentration-flow rate with a dual closed loop according to claim 2, characterized in that, The methods for determining the current coupling interference level include: Concentration deviation status indicators are classified into three types: high concentration, moderate concentration, and low concentration. Flow velocity deviation status indicators are classified into three types: fast flow velocity, moderate flow velocity, and slow flow velocity. A nine-square grid combination matrix of concentration deviation status indicators and flow velocity deviation status indicators is established, with each cell in the matrix corresponding to a specific two-parameter deviation combination status. The combination status of moderate concentration and moderate flow velocity is marked as no coupling interference level, the combination status of concentration deviation and flow velocity deviation deviating in the same direction is marked as weak coupling interference level, and the combination status of concentration deviation and flow velocity deviation deviating in opposite directions is marked as strong coupling interference level.

4. The intelligent control method for iron tailings paste filling concentration-flow rate with a dual closed loop according to claim 3, characterized in that, The concentration closed-loop control channel drives the feeding device and dilution water valve assembly to perform concentration adjustment actions, including: The system receives control commands for concentration parameters from the coordinated adjustment command sequence, and parses them to obtain the concentration adjustment direction and single-step concentration adjustment amount. When the concentration adjustment direction is to increase, it sends an acceleration command to the feeding device to increase the feeding rate of dry iron tailings, and simultaneously sends a flow reduction command to the dilution water valve group to reduce the injection flow rate of dilution water. When the concentration adjustment direction is to decrease, it sends a deceleration command to the feeding device to reduce the feeding rate of dry iron tailings, and simultaneously sends a flow increase command to the dilution water valve group to increase the injection flow rate of dilution water. Based on the single-step concentration adjustment amount, it calculates the change in rotation speed of the feeding device and the change in opening of the dilution water valve group, and adds the calculation result as an execution parameter to the acceleration command, deceleration command, flow increase command, or flow reduction command. After the command is issued, it starts a concentration response timer, and after the timer reaches the preset concentration response waiting time, it collects a new real-time concentration value and verifies whether the adjustment action is effective.

5. The intelligent control method for iron tailings paste filling concentration-flow rate with a dual closed loop according to claim 4, characterized in that, The flow rate closed-loop control channel drives the filling pump unit to perform flow rate regulation actions, including: The system receives control commands for flow rate parameters from the coordinated adjustment command sequence, parses them to obtain the flow rate adjustment direction and single-step flow rate adjustment amount; based on the current number of operating pumps in the filling pump group and the rated displacement range of a single pump, it determines whether the single-step flow rate adjustment amount exceeds the adjustment margin provided by the current number of operating pumps; when the single-step flow rate adjustment amount does not exceed the adjustment margin, it only adjusts the displacement setting value of the currently operating pumps and sends a displacement change command to each operating pump; when the single-step flow rate adjustment amount exceeds the adjustment margin and the flow rate adjustment direction is increasing, it starts the standby pump to join the operation and share the displacement increment, and sends a grid connection and commissioning command to the newly started standby pump; when the single-step flow rate adjustment amount exceeds the adjustment margin and the flow rate adjustment direction is decreasing, it cuts off the operating pump with the lowest displacement and the remaining pumps bear the displacement reduction, and sends a shutdown and exit command to the cut-off pump; after the pump group adjustment command is issued, it starts the flow rate response timer, and after the timer reaches the preset flow rate response waiting time, it collects a new real-time flow rate value and verifies whether the adjustment action is effective.

6. The intelligent control method for iron tailings paste filling concentration-flow rate with a dual closed loop according to claim 5, characterized in that, Interlock protection conditions are set between the two channels, and significant adjustments are made, including: Define significant adjustment thresholds for the concentration channel and the flow rate channel. When the single-step adjustment amount of either channel exceeds its corresponding significant adjustment threshold, the channel is determined to be in a significant adjustment state. When both the concentration channel and the flow rate channel are in a significant adjustment state simultaneously, interlock protection is triggered, suspending the execution of adjustment commands for the channel containing the slave adjustment parameter, allowing only the channel containing the master adjustment parameter to complete the current adjustment action. After the channel containing the master adjustment parameter completes the current adjustment action and a preset interlock release waiting time has elapsed, the suspension lock on the channel containing the slave adjustment parameter is released, allowing the channel containing the slave adjustment parameter to continue executing the suspended adjustment command. During the interlock protection triggering period, the pipeline inlet pressure is continuously monitored. If abnormal fluctuations occur in the inlet pressure, the interlock release waiting time is extended until the pressure returns to stability.

7. The intelligent control method for iron tailings paste filling concentration-flow rate with a dual closed loop according to claim 6, characterized in that, Continuous monitoring of pressure distribution along the pipeline and end-fill flow rate, including: Pressure sensors are installed at multiple key locations along the pipeline to collect pressure readings from each sensor in real time and calculate the pressure difference between adjacent sensors. The pressure difference of each section is compared with the theoretical pressure drop of that section of the pipeline under the current concentration and flow rate conditions. When the measured pressure difference exceeds the preset deviation multiple of the theoretical pressure drop, it is determined that there are signs of local blockage in that section of the pipeline. A flow sensor is installed at the inlet of the filling borehole at the end of the pipeline to collect the end filling flow rate in real time and compare it with the theoretical flow rate corresponding to the lower limit of the flow velocity target range. When the end filling flow rate is continuously lower than the theoretical flow rate for a preset period of time, it is determined that there is an abnormal decrease in flow rate. Based on the combined results of local obstruction symptom assessment and abnormal flow rate decline assessment, a pipe blockage warning signal is generated when either of the two conditions is met, and an emergency pipe blockage signal is generated when both conditions are met simultaneously.

8. The intelligent control method for iron tailings paste filling concentration-flow rate with a dual closed loop according to claim 7, characterized in that, Pause the execution of the current adjustment command sequence and switch to emergency evacuation control mode, including: When the signal is a pipe blockage warning signal or a pipe blockage emergency signal, immediately lock the execution status of the current coordinated regulation command sequence, stop sending new regulation commands to the feeding device, dilution water valve group, and filling pump group; send a frequency reduction operation command to the filling pump group to reduce the pump group's operating frequency to the preset unblocking mode operating frequency, and at the same time send a full opening command to the dilution water valve group to quickly dilute the high concentration paste in the pipeline; during the process of frequency reduction operation and dilution water injection, continuously monitor the pipeline inlet pressure and end filling flow rate. When the inlet pressure drops back to the normal range and the end flow rate recovers to above the preset recovery ratio of the theoretical flow rate, it is determined that the pipeline unblocking is completed; after the pipeline unblocking is completed, send a frequency increase recovery command to the filling pump group to gradually restore the pump group's operating frequency to the normal level, and send a flow rate callback command to the dilution water valve group to restore the dilution water flow rate to the normal injection volume; after the pump group frequency and dilution water flow rate have both returned to normal, release the command execution lock, clear the paused coordinated regulation command sequence, re-collect real-time concentration values ​​and real-time flow rate values, and enter a new round of regulation cycle.

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