A test system and method for automatic control of pumping flow rate of gangue cementing filling slurry

Abstract

The present invention provides a gangue cementing filling slurry pumping flow automatic control test system and method, belonging to the technical field of coal mine filling slurry pipeline pumping automatic control, the system includes a slurry pumping module, a resistivity monitoring module and a frequency conversion control module; the slurry pumping module includes a filling pump and a slurry delivery pipeline, the slurry delivery pipeline is provided with a test point, and the pipe wall of the test point is provided with a test hole; the resistivity monitoring module includes a monitoring electrode, an insulating sleeve, an electrode fixing frame, a test wire and a resistance test host; the electrode fixing frame is arranged around the outside of the test point; the monitoring electrode is installed on the test hole through the electrode fixing frame ring; the frequency conversion control module includes a frequency converter, a controller and a computer, the frequency converter is respectively connected to the filling pump and the controller, and the controller is respectively connected to the resistance test host and the computer. The present invention can effectively reduce the risk of pipe blockage caused by segregation during the transportation of gangue cementing filling slurry.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic control of coal mine filling slurry pipeline pumping, and in particular relates to a gangue cementing filling slurry pumping flow automatic control test system and method. Background Art

[0002] The cemented filling mining technology in coal mine goafs supports the overlying strata and controls the surface subsidence by constructing filling bodies in the goafs. As a green mining technology for coal mines, this technology has broad application prospects in "three-down" coal pressure mining, water conservation mining, and residual coal mining. Filling materials are the core of filling mining. Coal mine cemented filling slurry is a composite slurry composed of multiple materials and multiple particle sizes. Due to the space limitations of coal mines underground, cemented filling slurry is usually prepared on the ground and pressurized by a filling pump before being transported to the filling working face through a pipeline. The length of the filling pipeline can be several thousand meters. Therefore, ensuring the smooth flow of the filling pipeline transportation system is a key link in filling mining. In order to effectively improve the strength and durability of the filling body, coarse-grained (>5mm) coal gangue is often added to the filling material. However, the addition of coarse particles makes it easy for the slurry to settle during transportation and cause pipe blocking accidents, which not only hinders the smooth progress of filling mining, but also brings huge economic losses. Therefore, reducing the probability of sedimentation-type pipe blockage accidents is the key to ensuring the safe operation of filling pipelines.

[0003] Implementing monitoring of the segregation degree of slurry in the filling pipeline can provide an early warning for sedimentation-type pipe blocking accidents. Due to the non-transparency of the filling slurry and the filling pipeline, the segregation degree of the slurry inside the pipeline cannot be directly observed. Chinese patent CN103728371 A discloses a detection method and monitoring device for judging the segregation and settlement state of slurry in the pipeline using ultrasound. Three pairs of ultrasonic transmitting and receiving probes are arranged at three levels along the vertical direction of the pipeline. The concentration of slurry between different ultrasonic probes is calculated by the ultrasonic signals received by different probes, thereby judging the segregation and settlement state of slurry; Chinese patent CN109298025 B discloses a test device and method for monitoring the segregation of paste filling slurry in the pipeline, and a method for monitoring the segregation degree of slurry using the horizontal, vertical, and radial resistivity of the slurry in the filling pipeline at different orientations. The above patent provides a method for monitoring the segregation of filling slurry in the pipeline, and its role is only to provide an early warning for sedimentation-type pipe blocking accidents, and it is impossible to reduce the risk of pipe blocking by controlling the pumping system.

[0004] During the transportation of filling slurry containing coarse aggregate, flow rate is an important factor affecting the settlement of coarse aggregate. The greater the flow rate, the smaller the settlement of coarse particles and the lower the risk of pipe blockage.

[0005] The filling slurry delivery pump and the concrete pump have similar structural principles, and existing literature has reported on the flow control of concrete pumps. Patent CN103047121A discloses an electric concrete pump and its construction control method, and CN204436762 U discloses a concrete electric pump with variable frequency speed regulation function. Both control the flow of the concrete pump according to the outlet pressure of the main oil pump and by controlling the frequency converter to achieve the purpose of matching the output power of the motor. Patent CN105298135 A uses a frequency converter to achieve stepless speed regulation of a towed concrete pump. The above patents focus on variable frequency flow control, and its feedback link is the outlet pressure of the main oil pump. Its purpose is to save energy, and it does not perform closed-loop flow control for the purpose of reducing segregation pipe blockage. Summary of the invention

[0006] The purpose of the present invention is to provide a test system and method for automatic control of the pumping flow rate of gangue cemented filling slurry, which can effectively reduce the risk of pipe blockage caused by segregation during the transportation of gangue cemented filling slurry by controlling the flow rate of the pumping system based on real-time monitoring of the degree of slurry settlement in the pipeline.

[0007] The present invention provides a gangue cementing filling slurry pumping flow automatic control test system, comprising a slurry pumping module, a resistivity monitoring module and a frequency conversion control module;

[0008] The slurry pumping module includes a filling pump and a slurry delivery pipeline, the outlet of the filling pump is connected to the inlet of the slurry delivery pipeline, a test point is arranged on the slurry delivery pipeline, and n groups of test holes are arranged on the pipe wall of the test point, n is an integer greater than 2 and less than 8, the n groups of test holes are all located in the same circular section, the two test holes in the same group are symmetrically arranged with the reference diameter of the circular section as the symmetry axis, the test holes on the same side of the reference diameter are arranged at equal intervals, and the reference diameter is the vertical diameter of the horizontal section of the slurry delivery pipeline;

[0009] The resistivity monitoring module includes a monitoring electrode, an insulating sleeve, an electrode fixing frame, a test wire and a resistance test host; the electrode fixing frame is arranged around the outside of the test point and is provided with mounting holes corresponding to the test holes one by one; the monitoring electrode includes an inner electrode rod, an arc-shaped electrode block and an outer electrode rod, the height of the inner electrode rod is consistent with the thickness of the pipe wall of the test point, and the height of the outer electrode rod is greater than the thickness of the electrode fixing frame; the insulating sleeve includes an inner insulating sleeve and an outer insulating sleeve, the inner insulating sleeve is sleeved on the side of the inner electrode rod and the inner arc surface of the arc-shaped electrode block, the outer insulating sleeve is sleeved on the side of the outer electrode rod and the outer arc surface of the arc-shaped electrode block, and the height of the outer insulating sleeve on the outer electrode rod is consistent with the thickness of the electrode fixing frame; the inner insulating sleeve of the inner electrode rod and the side is inserted into the test hole, the outer insulating sleeve of the outer electrode rod and the side is inserted into the mounting hole, and the insulating sleeves on the inner and outer arc surfaces of the arc-shaped electrode block are respectively attached to the outer wall of the test point and the inner wall of the electrode fixing frame; the two monitoring electrodes in the same group of test holes are connected to the same channel of the resistance test host through the test wire;

[0010] The frequency conversion control module comprises a frequency converter, a controller and a computer. The frequency converter is connected to the filling pump and the controller respectively, and the controller is connected to the resistance test host and the computer respectively.

[0011] The above-mentioned gangue cementing filling slurry pumping flow automatic control test system also includes a flow monitoring module; the flow monitoring module includes a flow sensor and a flow data collector, the flow sensor is installed on the slurry conveying pipeline, the flow sensor is connected to the flow data collector, and the flow data collector is connected to the controller.

[0012] Furthermore, the electrode fixing frame includes two semicircular steel rings, ear plates and bolts; the ear plates are welded to both ends of the semicircular steel rings, through holes are provided on the ear plates, and the bolts pass through the through holes to fix the two semicircular steel rings.

[0013] Furthermore, the monitoring electrode is made of copper, and the end surface of the inner electrode rod facing the slurry conveying pipeline and the end surface of the outer electrode rod located outside the electrode fixing frame are gold-plated.

[0014] Furthermore, 7 groups of test holes are arranged on the pipe wall of the test point, the central angle formed by two test holes in the top group and the bottom group is 45 degrees, and the central angle formed by two adjacent test holes on the same side of the reference diameter is 22.5 degrees.

[0015] Furthermore, the slurry conveying pipeline includes a first horizontal pipe, a second horizontal pipe, a first curved pipe, a third horizontal pipe, a second curved pipe, a fourth horizontal pipe, an S-shaped pipe, a grooved clamp and a non-perforated pipe clamp; the outlet of the filling pump is connected to the first horizontal pipe through a grooved clamp, and the second horizontal pipe, the first curved pipe, the third horizontal pipe, the second curved pipe and the fourth horizontal pipe are connected in sequence through the grooved clamp, one end of the S-shaped pipe is connected to the left end of the fourth horizontal pipe through a non-perforated pipe clamp, and the other end of the S-shaped pipe is placed above the filling pump hopper.

[0016] Furthermore, the test points are arranged on the horizontal pipe and the curved pipe.

[0017] The present invention also provides a method for automatically controlling the pumping flow rate of gangue cemented filling slurry, which is carried out using the above-mentioned gangue cemented filling slurry pumping flow rate automatic control test system, and comprises the following steps:

[0018] S1. Select a calibration tube with the same inner diameter and thickness as the slurry delivery pipeline, and open a calibration hole in the calibration tube that is the same as the test hole;

[0019] S2. Install the resistivity monitoring module on the calibration tube, prepare the calibration solution with known mass concentration, known resistivity and predetermined temperature, place the calibration tube vertically, pour the calibration solution into it, and then place the calibration tube horizontally to ensure that the liquid level is higher than the monitoring electrode;

[0020] S3. Connect the outer electrode rod of the monitoring electrode to the test wire, connect the test wire to the resistance test host, and connect the two monitoring electrodes in the same group of test holes to the same channel of the resistance test host;

[0021] S4. Test the resistance of each channel and calculate the device coefficient K of each set of monitoring electrodes according to formula (1):

[0022] K=ρ / R (1)

[0023] Where, R is the resistance of a single channel of the resistance test host, unit Ω; ρ is the resistivity of the calibration solution, unit Ω·m;

[0024] S5. Input the calculated device coefficient K into the controller;

[0025] S6. Prepare the filling slurry according to the established ratio, and continuously pump it by the filling pump. During the pumping process, the resistance test host collects the resistance of n groups of monitoring electrodes in real time, and the controller calculates the resistivity ρ between the i-th group of monitoring electrodes according to the following formula i and based on the resistivity ρ i Quantitative index of segregation degree SI:

[0026] ρ i =K·R i (2)

[0027]

[0028] In the formula, R i It represents the resistance of the channel connecting the resistance test host and the i-th group of monitoring electrodes, in Ω; represents the average resistivity of n groups of monitoring electrodes Ω·m, i is an integer and 1≤i≤n;

[0029] S7. The controller compares the measured segregation degree quantitative index SI with the set value SI0:

[0030] When SI=SI0, the controller output is 0 and the frequency converter does not work; when SI>SI0, the controller outputs the deviation signal △SI between SI and SI0, so that the output frequency of the frequency converter decreases, the speed of the motor in the filling pump is reduced, the output flow of the filling pump is reduced, SI is reduced, and SI=SI0 is gradually made; when SI<SI0, the controller outputs the deviation signal △SI between SI and SI0, controls the frequency converter to act, so that the output frequency of the frequency converter increases, the speed of the motor in the filling pump 1 is increased, the flow of the filling pump is increased, SI is increased, and SI=SI0 is gradually made.

[0031] Furthermore, the calibration solution is a sodium chloride solution with a mass concentration of 0.2%, a resistivity of 3.006 Ω·m, and a temperature of 18°C.

[0032] Furthermore, the horizontal tube used for calibration is an acrylic tube with one end closed and the other end open.

[0033] The present invention has the following beneficial effects.

[0034] The principle of the present invention is feasible. Resistivity is used as a monitoring medium for the distribution of coarse aggregate in gangue cemented filling slurry, and a segregation index based on resistivity is used as a feedback link to compare with a given segregation index. The difference between the two is processed by a controller to control a frequency converter to control the speed of a filling pump motor, thereby realizing automatic control of the pumping flow rate and effectively reducing the risks of pipe blockage and pipe wear. The specifications of the pipes used in the present invention can be determined according to test requirements and are easy to disassemble. Horizontal pipes and elbows can be added or reduced according to requirements during the experiment. The present invention can increase the resistivity monitoring position according to test requirements. The monitoring electrodes and electrode fixing frames used in the present invention do not require additional monitoring pipes, which greatly maintains the integrity of the original pipes and reduces the interference of the monitoring device on the flow field in the pipes. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 It is the horizontal layout diagram of the automatic control test system for the pumping flow of gangue cementing filling slurry;

[0037] Figure 2 for Figure 1 Sectional view along line AA;

[0038] Figure 3 is a schematic diagram of the monitoring electrode;

[0039] Figure 4 is a cross-sectional view of an electrode fixing frame;

[0040] In the figure, 1-filling pump, 2-first horizontal pipe, 3-second horizontal pipe, 4-first elbow, 5-third horizontal pipe, 6-second elbow, 7-fourth horizontal pipe, 8-S-shaped pipe, 9-grooved clamp, 10-non-perforated pipe clamp, 11-flow sensor, 12-flange, 13-flow data collector, 14-monitoring electrode, 15-insulating sleeve, 16-electrode fixing frame, 17-test wire, 18-resistance test host, 19-frequency converter, 20-controller, 21-computer, 22-inner insulating sleeve, 23-outer insulating sleeve, 24-inner electrode rod, 25-arc electrode block, 26-outer electrode rod, 27-semicircular steel ring, 28-ear plate, 29-bolt. DETAILED DESCRIPTION

[0041] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Example 1

[0043] The present embodiment provides a gangue cementing filling slurry pumping flow automatic control test system, including a slurry pumping module, a flow monitoring module, a resistivity monitoring module and a frequency conversion control module.

[0044] The slurry pumping module includes a filling pump 1 and a slurry delivery pipeline. The slurry delivery pipeline is arranged on a horizontal plane, including a first horizontal pipe 2, a second horizontal pipe 3, a first elbow pipe 4, a third horizontal pipe 5, a second elbow pipe 6, a fourth horizontal pipe 7, an S-shaped pipe 8, a groove clamp 9 and a non-perforated pipe clamp 10; the outlet of the filling pump 1 is connected to the first horizontal pipe 2 through a groove clamp 9, the second horizontal pipe 3, the first elbow pipe 4, the third horizontal pipe 5, the second elbow pipe 6, and the fourth horizontal pipe 7 are connected in sequence through the groove clamp 9, one end of the S-shaped pipe 8 is connected to the left end of the fourth horizontal pipe 7 through a non-perforated pipe clamp 10, and the other end of the S-shaped pipe 8 is placed above the hopper of the filling pump 1. Test points are arranged on the horizontal pipe and the curved pipe, and n groups of test holes are arranged on the pipe wall of the test points, where n is an integer greater than 2 and less than 8. The n groups of test holes are all located in the same circular section, and the two test holes in the same group are symmetrically arranged with the reference diameter of the circular section as the symmetry axis. The test holes on the same side of the reference diameter are arranged at equal intervals. The reference diameter is the vertical diameter of the horizontal section of the slurry conveying pipeline, and the reference diameter on the curved pipe is obtained by translating the vertical diameter on the horizontal pipe.

[0045] The flow monitoring module includes a flow sensor 11, a flange 12 and a flow data collector 13. The flow sensor 11 is connected between the first horizontal pipe 2 and the second horizontal pipe 3 through the flange 12. The flow sensor 11 is connected to the flow data collector 13, and the flow data collector 13 is connected to the controller 20.

[0046] The resistivity monitoring module includes a monitoring electrode 14, an insulating sleeve 15, an electrode fixing frame 16, a test wire 17 and a resistance test host 18; the electrode fixing frame 16 is arranged around the outside of the test point, including two semicircular steel rings 27, an ear plate 28 and a bolt 29; the ear plate 28 is welded to the two ends of the semicircular steel ring 27, a through hole is provided on the ear plate 28, and the bolt 29 passes through the through hole to fix the two semicircular steel rings 27, and the semicircular steel ring 27 is provided with mounting holes corresponding to the test holes; the monitoring electrode 14 includes an inner electrode rod 24, an arc electrode block 25 and an outer electrode rod 26, the height of the inner electrode rod 24 is consistent with the thickness of the pipe wall of the test point, and the height of the outer electrode rod 26 is greater than the thickness of the electrode fixing frame 16 and the difference is greater than or equal to 1cm; the insulating sleeve 15 includes an inner insulating sleeve 22 and an outer insulating sleeve 23, the inner insulating sleeve 22 is sleeved on the side of the inner electrode rod 24 and the arc electrode block 25. On the inner arc surface of the electrode block 25, the outer insulating sleeve 23 is sleeved on the side of the outer electrode rod 26 and the outer arc surface of the arc electrode block 25, and the height of the outer insulating sleeve 23 sleeved on the outer electrode rod 26 is consistent with the thickness of the electrode fixing frame 16; the inner electrode rod 24 and the inner insulating sleeve 22 on the side are inserted into the test hole, the outer electrode rod 26 and the outer insulating sleeve 23 on the side are inserted into the mounting hole, and the insulating sleeves on the inner and outer arc surfaces of the arc electrode block 25 are respectively attached to the outer wall of the test point and the inner wall of the electrode fixing frame 16; the two monitoring electrodes 14 in the same group of test holes are connected to the same channel of the resistance test host 18 through the test wire 17.

[0047] The frequency conversion control module includes a frequency converter 19 , a controller 20 and a computer 21 . The frequency converter 19 is connected to the filling pump 1 and the controller 20 , respectively. The controller 20 is connected to the resistance test host 18 and the computer 21 , respectively.

[0048] Furthermore, the monitoring electrode 14 is made of copper, and the end surface of the inner electrode rod 24 facing the slurry conveying pipeline and the end surface of the outer electrode rod 26 located outside the electrode fixing frame 16 are gold-plated.

[0049] Furthermore, 7 groups of test holes are arranged on the pipe wall of the test point, the central angle formed by two test holes in the top group and the bottom group is 45 degrees, and the central angle formed by two adjacent test holes on the same side of the reference diameter is 22.5 degrees.

[0050] In the above scheme, the rated flow rate of filling pump 1 is 30m 3 / h, the first horizontal pipe 2, the second horizontal pipe 3, the first elbow 4, the third horizontal pipe 5, the second elbow 6, and the fourth horizontal pipe 7 are made of seamless steel pipes, the S-shaped pipe 8 is a steel hose, the inner diameter of all pipes is 100mm, the wall thickness is 4mm, the length of the first horizontal pipe 2 is 300mm, the length of the second horizontal pipe 3 is 7500mm, the first elbow 4 and the second elbow 6 are 90-degree elbows with a curvature radius of 500mm, the length of the third horizontal pipe 5 is 1000mm, and the length of the fourth horizontal pipe 7 is 8000mm. The inner electrode rod 24 and the outer electrode rod 26 are cylindrical with a diameter of 5mm, the height of the inner electrode rod 24 is 4mm, and the height of the outer electrode rod 26 is 30mm. The ends of the inner electrode rod 24 and the outer electrode rod 26 are plated with 0.5mm of gold. The thickness of the arc electrode block 25 is 6mm. The thickness of the inner insulating sleeve 22 and the outer insulating sleeve 23 is 2.5mm. The width of the semicircular steel ring 27 and the ear plate 28 is 50 mm, the thickness is 10 mm, and the inner radius of the semicircular steel ring 27 is 110 mm.

[0051] Example 2

[0052] The present embodiment provides a method for automatically controlling the pumping flow rate of gangue cemented filling slurry, which is performed using the above-mentioned automatic control test system for pumping flow rate of gangue cemented filling slurry and includes the following steps.

[0053] S1. Take an acrylic tube with the same inner diameter and thickness as the second horizontal tube 3 and a length of 200 mm as the calibration tube, seal one end of the acrylic tube, and open 14 calibration holes on the middle plane of the acrylic tube. The position and diameter of the calibration holes are consistent with the test holes on the second horizontal tube 3.

[0054] S2. Install the inner insulating sleeve 22 in the calibration hole, then insert the inner electrode rod 24 of the monitoring electrode 14 into the middle of the inner insulating sleeve 22, vertically place the acrylic tube with the sealed end facing downward, prepare a sodium chloride solution (18°C) with a mass concentration of 0.2% and a resistivity of 3.006Ω·m, and pour it from the upper end of the acrylic tube to ensure that the liquid level is higher than the monitoring electrode 14 after the acrylic tube is placed horizontally.

[0055] S3. Connect the outer electrode rod 26 of the monitoring electrode 14 to the test wire 17 , the test wire 17 is connected to the resistance test host 18 , and the two monitoring electrodes 14 in the same group of test holes are connected to the same channel of the resistance test host 18 .

[0056] S4. Calculate the device coefficient K of each group of monitoring electrodes 14 according to formula (1):

[0057] K=ρ / R (1)

[0058] Wherein, R is the resistance of a single channel of the resistance test host 18, in Ω; ρ is the resistivity of the calibration solution, in Ω·m.

[0059] S5. Input the calculated device system into the controller 20.

[0060] S6. Prepare the filling slurry according to the established ratio, pour it into the hopper of the filling pump 1 and continuously pump it. During the pumping process, the resistance test host 18 collects the resistance of the n groups of monitoring electrodes 14 in real time, and the controller 20 calculates the resistivity ρ between the i-th group of monitoring electrodes 14 according to the following formula i and based on the resistivity ρ i Quantitative index of segregation degree SI:

[0061] ρ i =K·R i (2)

[0062]

[0063] In the formula, R i represents the resistance of the channel connecting the resistance test host 18 and the i-th group of monitoring electrodes 14, in Ω; Ω·m represents the average value of the resistivity of n sets of monitoring electrodes 14 , where i is an integer and 1≤i≤n.

[0064] S7. The controller 20 compares the measured quantitative index SI of the degree of segregation with the set value SI0: when SI=SI0, the controller output is 0, and the frequency converter 19 does not act; when SI>SI0, the controller 20 outputs the deviation signal △SI of SI and SI0, so that the frequency converter 19 output frequency decreases, reduces the speed of the motor in the filling pump 1, reduces the output flow of the filling pump 1, and reduces SI, gradually making SI=SI0; when SI<SI0, the controller 20 outputs the deviation signal △SI of SI and SI0, controls the frequency converter 19 to act, so that the frequency converter 19 output frequency increases, increases the speed of the motor in the filling pump 1, increases the flow of the filling pump 1, increases SI, and gradually makes SI=SI0. In this process, the change of SI over time is recorded in real time.

[0065] S8. After the test is completed, the outlet of the S-shaped tube 8 is placed in a waste pool, and clean water is pumped by the filling pump 1 to wash the tube. When the water flow at the outlet of the S-shaped tube 8 is clear, stop pumping, disassemble the various parts, and clean the remaining material at the bottom of the pipe.

[0066] The principle of the present invention is as follows: the gangue cemented filling slurry contains a large number of gangue particles with a particle size greater than 5mm. When the slurry ratio is unreasonable and the flow rate is low, the coarse gangue will settle to the bottom of the pipeline during the slurry transportation process. When the settlement reaches a certain degree, it will cause a pipe blockage accident, interfering with the normal filling and mining. After the coarse aggregate in the pipeline settles, the coarse aggregate is unevenly distributed in the vertical direction. By monitoring the resistivity at different heights and calculating the segregation index, the uniformity of the coarse aggregate distribution can be reflected. When the segregation index obtained by real-time monitoring and calculation is less than the given segregation index, it means that the settlement degree of the coarse aggregate increases. At this time, the controller will control the frequency of the inverter to increase and increase the flow rate of the filling pump. When the flow rate increases, the coarse aggregate will be re-suspended, so that the uniformity of the coarse aggregate distribution is enhanced, the resistivity segregation index increases, and the risk of pipe blockage is reduced. When the segregation index obtained through real-time monitoring and calculation is greater than the given segregation index, the controller will control the frequency of the frequency converter to decrease and reduce the filling pump flow rate, so that the resistivity segregation index gradually approaches the initial set value, reducing the risk of pipeline wear.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gangue cementing filling slurry pumping flow automatic control test system, characterized in that: It includes slurry pumping module, resistivity monitoring module and frequency conversion control module; The slurry pumping module comprises a filling pump (1) and a slurry delivery pipeline, the outlet of the filling pump (1) is connected to the inlet of the slurry delivery pipeline, a test point is arranged on the slurry delivery pipeline, and n groups of test holes are arranged on the pipe wall of the test point, n is an integer greater than 2 and less than 8, the n groups of test holes are all located in the same circular section, two test holes in the same group are symmetrically arranged with the reference diameter of the circular section as the symmetry axis, the test holes located on the same side of the reference diameter are arranged at equal intervals, and the reference diameter is the vertical diameter of the horizontal section of the slurry delivery pipeline; The resistivity monitoring module comprises a monitoring electrode (14), an insulating sleeve (15), an electrode fixing frame (16), a test lead (17) and a resistance testing host (18); The electrode fixing frame (16) is arranged around the outside of the test point and is provided with mounting holes corresponding to the test holes one by one; The monitoring electrode (14) comprises an inner electrode rod (24), an arc-shaped electrode block (25) and an outer electrode rod (26), the height of the inner electrode rod (24) being consistent with the thickness of the pipe wall at the test point, and the height of the outer electrode rod (26) being greater than the thickness of the electrode fixing frame (16); The insulating sleeve (15) comprises an inner insulating sleeve (22) and an outer insulating sleeve (23), the inner insulating sleeve (22) being sleeved on the side surface of the inner electrode rod (24) and the inner arc surface of the arc-shaped electrode block (25), and the outer insulating sleeve (23) being sleeved on the side surface of the outer electrode rod (26) and the outer arc surface of the arc-shaped electrode block (25), and the height of the outer insulating sleeve (23) sleeved on the outer electrode rod (26) being consistent with the thickness of the electrode fixing frame (16); The inner electrode rod (24) and the inner insulating sleeve (22) on the side are inserted into the test hole, the outer electrode rod (26) and the outer insulating sleeve (23) on the side are inserted into the mounting hole, and the insulating sleeves on the inner and outer arc surfaces of the arc-shaped electrode block (25) are respectively attached to the outer wall of the test point and the inner wall of the electrode fixing frame (16); Two monitoring electrodes (14) in the same group of test holes are connected to the same channel of a resistance test host (18) via a test wire (17); The frequency conversion control module comprises a frequency converter (19), a controller (20) and a computer (21); the frequency converter (19) is connected to the filling pump (1) and the controller (20) respectively; and the controller (20) is connected to the resistance test host (18) and the computer (21) respectively.

2. The automatic control test system for pumping flow of gangue cemented filling slurry according to claim 1 is characterized in that: Also includes a flow monitoring module; The flow monitoring module comprises a flow sensor (11) and a flow data collector (13); the flow sensor (11) is installed on the slurry conveying pipeline; the flow sensor (11) is connected to the flow data collector (13); and the flow data collector (13) is connected to the controller (20).

3. The automatic control test system for pumping flow rate of gangue cemented filling slurry according to claim 2 is characterized in that: The electrode fixing frame (16) comprises two semicircular steel rings (27), a lug plate (28) and a bolt (29); The ear plate (28) is welded to the two ends of the semicircular steel ring (27). A through hole is provided on the ear plate (28). Bolts (29) pass through the through hole to fix the two semicircular steel rings (27).

4. The gangue cementing filling slurry pumping flow automatic control test system according to claim 3 is characterized in that: The monitoring electrode (14) is made of copper, and the end surface of the inner electrode rod (24) facing the slurry conveying pipeline and the end surface of the outer electrode rod (26) located outside the electrode fixing frame (16) are plated with gold.

5. The automatic control test system for pumping flow rate of gangue cemented filling slurry according to claim 4 is characterized in that: There are 7 groups of test holes on the pipe wall of the test point. The central angle formed by the two test holes in the top group and the bottom group is 45 degrees, and the central angle formed by the two adjacent test holes on the same side of the reference diameter is 22.5 degrees.

6. The automatic control test system for pumping flow rate of gangue cemented filling slurry according to claim 5 is characterized in that: The slurry conveying pipeline comprises a first horizontal pipe (2), a second horizontal pipe (3), a first elbow pipe (4), a third horizontal pipe (5), a second elbow pipe (6), a fourth horizontal pipe (7), an S-shaped pipe (8), a grooved clamp (9) and a non-perforated pipe clamp (10); The outlet of the filling pump (1) is connected to the first horizontal pipe (2) through a grooved clamp (9); the second horizontal pipe (3), the first curved pipe (4), the third horizontal pipe (5), the second curved pipe (6), and the fourth horizontal pipe (7) are connected in sequence through the grooved clamp (9); one end of the S-shaped pipe (8) is connected to the left end of the fourth horizontal pipe (7) through a non-perforated pipe clamp (10); and the other end of the S-shaped pipe (8) is placed above the hopper of the filling pump (1).

7. The gangue cementing filling slurry pumping flow automatic control test system according to claim 6 is characterized in that: The test points are arranged on horizontal pipes and curved pipes.

8. A test method for automatic control of pumping flow rate of gangue cemented filling slurry, characterized in that: The test is carried out using the automatic control test system for pumping flow of gangue cementing filling slurry according to any one of claims 1 to 7, comprising the following steps: S1. Select a calibration tube with the same inner diameter and thickness as the slurry delivery pipeline, and open a calibration hole in the calibration tube that is the same as the test hole; S2. Install the resistivity monitoring module on the calibration tube, configure a calibration solution with a known mass concentration, known resistivity and a predetermined temperature, place the calibration tube vertically, pour the calibration solution into it, and then place the calibration tube horizontally to ensure that the liquid level is higher than the monitoring electrode (14); S3. The outer electrode rod (26) of the monitoring electrode (14) is connected to the test wire (17), the test wire (17) is connected to the resistance test host (18), and the two monitoring electrodes (14) in the same group of test holes are connected to the same channel of the resistance test host (18); S4. Test the resistance of each channel and calculate the device coefficient K of each group of monitoring electrodes (14) according to formula (1): K=ρ / R (1) Where, R is the resistance of a single channel of the resistance test host (18), unit Ω; ρ is the resistivity of the calibration solution, unit Ω·m; S5. The calculated device coefficient K is input into the controller (20); S6. A filling slurry is prepared according to a predetermined ratio and continuously pumped by a filling pump (1). During the pumping process, the resistance test host (18) collects the resistance of n groups of monitoring electrodes (14) in real time, and the controller (20) calculates the resistivity ρ between the i-th group of monitoring electrodes (14) according to the following formula: i and based on the resistivity ρ i Quantitative index of segregation degree SI: r i =K·R i (2) In the formula, R i represents the resistance of the channel connecting the resistance test host (18) and the i-th group of monitoring electrodes (14), in units of Ω; represents the average value (Ω·m) of the resistivity of n groups of monitoring electrodes (14), i is an integer and 1≤i≤n; S7. The controller (20) compares the measured quantitative index SI of the degree of segregation with the set value SI0: When SI=SI0, the controller (20) outputs 0 and the frequency converter (19) does not operate; when SI>SI0, the controller (20) outputs a deviation signal △SI between SI and SI0, so that the output frequency of the frequency converter (19) decreases, the rotation speed of the motor in the filling pump (1) is reduced, the output flow rate of the filling pump (1) is reduced, SI decreases, and SI gradually becomes SI0; when SI<SI0, the controller (20) outputs a deviation signal △SI between SI and SI0, controls the frequency converter (19) to operate, so that the output frequency of the frequency converter (19) increases, the rotation speed of the motor in the filling pump (1) is increased, the flow rate of the filling pump (1) is increased, SI increases, and SI gradually becomes SI0.

9. The method for automatically controlling the pumping flow rate of gangue cemented filling slurry according to claim 8, characterized in that: The calibration solution is a sodium chloride solution with a mass concentration of 0.2%, a resistivity of 3.006Ω·m, and a temperature of 18°C.

10. The test method for automatic control of pumping flow rate of gangue cemented filling slurry according to claim 9, characterized in that: The horizontal tube used for calibration is an acrylic tube with one end closed and the other end open.

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