A complete solid waste paste filling process system suitable for complex working conditions

Abstract

This invention provides a complete solid waste paste backfilling process system suitable for complex working conditions, belonging to the field of metal mine backfilling technology. The system includes a tailings thickening system, a water collection and thickening system, a waste rock addition system, a cementitious material addition system, a paste mixing system, and a pump-pressure pipeline transportation system. These systems are interconnected and controlled by an intelligent control system. The material distribution framework provided by this invention has multi-stage material stabilization functions, effectively achieving accurate weighing and stable distribution of various materials. Addressing the complex rheological characteristics of the slurry, a combination of primary continuous double-helix blade mixing and secondary four-phase impeller + continuous single-helix blade mixing is used to achieve continuous homogenization mixing and stirring of ultra-fine-grained tailings and high-content, large-grained coarse aggregates. A high-pressure full-pipe transportation mode is adopted, with horizontal pipelines using nano-composite wear-resistant pipes, fully utilizing deep well transportation conditions to achieve efficient and stable transportation of paste slurry under high-flow, long-distance conditions.

Description

Technical Field

[0001] This invention relates to the field of metal mine backfilling technology, and in particular to a full solid waste paste backfilling process system suitable for complex working conditions. Background Technology

[0002] Backfilling mining is a green and safe mining method. Compared with traditional cemented backfilling, paste backfilling has the advantages of no bleeding, no segregation, no stratification, and high integrity of the backfill body. Using whole tailings instead of graded tailings to prepare paste slurry is the mainstream trend in the development of mine backfilling technology. However, the improvement of mineral processing technology has increased the content of clay-like components such as ultrafine particles and fine particles (≤20μm, ≤74μm) in tailings, which has led to a sharp decrease in the strength of the backfill body. At the same time, with the gradual promotion of cleaner production in the mining industry, backfilling cementitious materials are gradually transitioning from traditional silicate cement to solid waste alkali-activated cementitious materials. However, the new cementitious materials activated by solid waste generally have the problem of low cementitious strength. To compensate for the low strength of the backfill caused by the clay components in the tailings, while controlling backfill costs and meeting the strength requirements of the backfill body, it has become an effective method to mix crushed and screened tunneling waste rock, rod mill sand and other coarse aggregates into the backfill material. This material combination of tailings and coarse aggregates, as well as the paste backfill system that is compatible with it, has been gradually promoted on a small scale.

[0003] The stable preparation and efficient transportation of backfill slurry are crucial for ensuring effective backfilling in mining operations. Currently, paste-based backfilling processes used in the industry are mostly suitable for applications with small backfilling capacity requirements (flow rate 50-80 m³ / h). 3 Mines with relatively simple operating conditions, such as short conveying distances (horizontal distance ≤ 2km) and no stringent requirements for filling strength, are particularly vulnerable. Even subtle changes in the proportions of paste materials have a significant impact on the rheological properties of the paste. A stable material proportion is a prerequisite for ensuring uniform strength distribution in the filling body. The preparation of large-volume pastes can easily amplify material weighing errors and batching fluctuations, severely affecting filling quality and the stable operation of the filling system. This places higher demands on the accurate weighing, stable addition, and automated control of various materials. To improve filling strength, the homogenization of ultra-fine-grained tailings mixed with higher-content, larger-grained coarse aggregates presents new challenges to continuous mixing processes. Deep well and long-distance pipeline transportation of large-grained coarse aggregate paste structures faces technical challenges such as high-pressure pipe resistance, high-pressure pipe pressure, and high wear, leading to a sharp increase in the risk of pipe blockage and rupture accidents in the filling pipeline.

[0004] Engineering examples show that for complex filling conditions in mines with large filling flow rates, long pipeline distances, high requirements for filling body strength, homogeneity, and integrity, high slurry concentration, and large particle size and wide particle size range of filling materials, the existing paste filling process cannot meet the complex paste preparation and transportation needs. Summary of the Invention

[0005] This invention addresses the technical challenges of paste filling under complex filling conditions, such as large filling flow rates, long pipeline distances, high requirements for filling strength, homogeneity, and integrity, high slurry concentration, and large particle size and wide particle size range of filling materials. It provides a comprehensive solid waste paste filling process system suitable for complex conditions, achieving homogenized preparation of pastes with high homogeneity, high strength, and complex material particle size composition, and ensuring stable and efficient transportation under deep well, high flow rate, and long-distance conditions. This improves the quality of mine filling and ensures production safety.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] A complete solid waste paste backfilling process system suitable for complex working conditions includes a tailings thickening system, a water collection and thickening system, a waste rock addition system, a cementitious material addition system, a paste mixing system, and a pump-pressurized pipeline transportation system. The above systems are interconnected and controlled by an intelligent control system.

[0008] The tailings thickening system includes a flocculant preparation system, a deep cone thickener, an underflow discharge pipeline, an underflow low-level circulation pipeline, and an underflow high-level circulation pipeline.

[0009] The water collection and concentration system includes an overflow tank, a bottom flow concentration pipeline, a stirring concentration pipeline, and a spray water supply pipeline;

[0010] The waste rock addition system includes a waste rock receiving bin, a belt conveyor, a waste rock stabilizing bin, and a quantitative feeder;

[0011] The cementitious material addition system includes a cementitious material silo, a double-body separator wheel, a micro powder scale, and a screw conveyor.

[0012] The paste mixing system includes a spray dust suppression system, a primary twin-shaft horizontal mixer, and a secondary twin-shaft horizontal mixer;

[0013] The pump-pressurized pipeline system includes a filling plunger pump and a filling pipeline system;

[0014] The intelligent control system includes intelligent control software, electrically controlled valves, electrically controlled centrifugal pumps, electrically controlled variable frequency slurry pumps, concentration meters, and flow meters;

[0015] The industrial water supply system is connected to the flocculant preparation system and the static mixer via pipelines, and electrically controlled valves are installed on the connecting pipelines.

[0016] The flocculant preparation system is connected to a static mixer via an electrically controlled centrifugal pump. The static mixer is connected to a central feed cylinder via a pipeline. The central feed cylinder is located at the upper center of the deep cone thickener.

[0017] The tailings conveying station of the concentrator is connected to the central feed cylinder via pipeline;

[0018] The overflow from the top of the deep cone thickener is transported to the overflow tank through a pipeline, and the bottom of the overflow tank is connected to the deep cone thickener and the underflow thickening pipeline through an electrically controlled centrifugal pump.

[0019] An electrically controlled valve is installed near the overflow tank in the pipeline between the overflow tank and the deep cone thickener. After the electrically controlled valve, the pipeline splits into two branches. One branch is connected to the bottom of the deep cone thickener through an electrically controlled variable frequency slurry pump and an electrically controlled valve. The other branch is equipped with a concentration meter. After the concentration meter, the pipeline is connected to the underflow high-level circulation pipeline and the underflow low-level circulation pipeline of the deep cone thickener through electrically controlled valves.

[0020] The underflow thickening pipeline is divided into two branches. One branch is connected to the spray water supply pipeline and the stirring thickening pipeline respectively after passing through a flow meter. The other branch is connected to the underflow discharge pipeline through an electrically controlled valve.

[0021] The underflow discharge pipeline is led out from the bottom of the deep cone thickener. An electrically controlled valve and an electrically controlled variable frequency slurry pump are installed near the bottom of the deep cone thickener. A branch of the underflow thickening pipeline merges into the pipeline after the electrically controlled variable frequency slurry pump. A concentration meter, a flow meter and an electrically controlled valve are installed on the pipeline after the electrically controlled variable frequency slurry pump.

[0022] The underflow discharge pipeline and the mixing and thickening pipeline converge into the first-stage twin-shaft horizontal mixer, and the spray water supply pipeline is connected to the spray dust suppression system at the top of the first-stage twin-shaft horizontal mixer;

[0023] Waste rock in the waste rock dump is transported to the waste rock receiving bin, which is then connected to the waste rock stabilizing bin via a belt conveyor. The waste rock stabilizing bin feeds the waste rock into the primary twin-shaft horizontal mixer via a quantitative feeder.

[0024] The material in the cement truck is transported to the cementitious silo through pipelines. The cementitious silo feeds the material to the screw conveyor through the micro powder scale. The screw conveyor then sends the material to the first-stage twin-shaft horizontal mixer.

[0025] The primary twin-shaft horizontal mixer is connected to the secondary twin-shaft horizontal mixer. The secondary twin-shaft horizontal mixer is connected to the filling pipeline system via a filling plunger pump. The filling pipeline system is connected to the goaf.

[0026] The bottom of the gelling silo is equipped with a double-body partition wheel.

[0027] A flow meter and a concentration meter are installed on the connecting pipe between the filling plunger pump and the filling pipeline system.

[0028] The mixing blades of the first-stage twin-shaft horizontal mixer are continuous double-helix blades.

[0029] The mixing blades of the two-stage twin-shaft horizontal mixer are four-phase paddle blades plus continuous single-helix blades.

[0030] In the filling pipeline system, the diameter of the vertical pipe is greater than the diameter of the horizontal pipe.

[0031] The horizontal pipes in the filling pipeline system are nanocomposite wear-resistant pipes.

[0032] The underflow high-level circulation pipeline is located on one side of the upper part of the deep cone thickener cylinder, and its position is lower than the central feed cylinder; the underflow low-level circulation pipeline is located on one side of the upper part of the deep cone thickener cone, and its position is higher than the deep cone thickener cone.

[0033] In this invention,

[0034] The flocculant preparation system is used to prepare flocculant solutions.

[0035] The deep cone thickener is used to thicken low-concentration tailings mortar, prepare and store high-concentration underflow tailings, and discharge overflow water.

[0036] The underflow discharge pipeline is used to discharge tailings from the deep cone thickener sludge layer, providing high-concentration tailings slurry to subsequent process stages.

[0037] The underflow low-level circulation pipeline is used to homogenize the tailings in the mud layer. It transports the tailings in the mud layer, whose concentration is distributed with height, to the upper part of the cone of the deep cone thickener for circulation, so as to homogenize the tailings in the mud layer and improve the uniformity and stability of the underflow tailings slurry concentration.

[0038] The bottom-flow high-level circulation pipeline is used to activate the tailings slurry layer, and transport the high-concentration tailings slurry layer to the upper part of the deep cone thickener cylinder for circulation thickening, thereby reducing the slurry layer height, reducing the rake frame torque, and preventing rake crushing accidents.

[0039] Overflow tanks are used to collect and store overflow water from deep cone thickeners.

[0040] The underflow thickening pipeline is used to adjust the underflow tailings concentration of the deep cone thickener. By introducing water from the overflow tank into the underflow discharge pipeline and the underflow low-level circulation pipeline, the high-concentration tailings are diluted with water to obtain the underflow tailings of the target concentration.

[0041] The stirring and thickening pipeline is used to output stirring and thickening water to subsequent process steps, so that the paste slurry reaches the designed target concentration.

[0042] The spray water supply line branches off from the mixing and concentration line to supply water to subsequent process stages.

[0043] The waste rock receiving bin is used to load and screen waste rock, remove large pieces of uncrushed waste rock to prevent them from affecting the operation of subsequent processes, and evenly feed the material to the belt conveyor for primary stable output.

[0044] Belt conveyors are used to transfer waste rock to waste rock silos.

[0045] The waste rock stabilization bin is used to load the waste rock after primary stabilization and to perform secondary stabilization of the waste rock, and then evenly outputs the waste rock to the quantitative feeder.

[0046] The quantitative feeder is used to measure and transport waste rock, so as to quantitatively input waste rock into subsequent process steps.

[0047] The cementitious material silo is used to load and store cementitious materials and to discharge them to the double-body separator wheel.

[0048] The double-body separator wheel is used to stabilize the material and to evenly distribute it to the micro powder scale.

[0049] Micro powder scales are used for metering and conveying cementitious materials.

[0050] Screw conveyors are used to transfer cementitious materials, providing a quantitative input of cementitious materials for subsequent process steps.

[0051] The spray dust suppression system is used to suppress dust from fine-particle materials fed into the primary twin-shaft horizontal mixer, control dust loss of each material, and improve the accuracy of material feeding.

[0052] The first-stage twin-shaft horizontal mixer is used to shear and mix the mixture, so that the various materials are evenly dispersed, and then push the materials into the second-stage twin-shaft horizontal mixer.

[0053] The two-stage twin-shaft horizontal mixer is used to lift large-particle materials, shear and mix various materials, ensure uniform dispersion of large-particle-size materials, achieve homogenization preparation of paste slurry, and push the paste slurry to subsequent process steps.

[0054] A filling plunger pump is used to provide power for conveying paste slurries.

[0055] The filling pipeline system is used to transport paste slurry to a designated elevation and horizontal location underground. The vertical pipeline has a larger diameter than the horizontal pipeline, forming a high-pressure full-pipe flow transportation mode, reducing pumping pressure, reducing vertical pipe pressure, and increasing the conveying speed and efficiency of the paste slurry; the horizontal pipeline is a nano-composite wear-resistant pipe, which effectively reduces pipe resistance, improves pipe pressure bearing capacity, and ensures stable and safe transportation of the slurry.

[0056] The above technical solution has at least the following advantages compared with the existing technology:

[0057] The above solution has a multi-stage material stabilization function, which can effectively realize the accurate weighing and stable feeding of various materials, control systemic feeding errors and losses, and ensure accurate and stable paste material ratio;

[0058] The paste mixing system is designed for the complex rheological characteristics of slurry materials. It uses a combination of primary continuous double helical blade mixing and secondary four-phase blade mixing + continuous single helical blade mixing mode. This enables continuous homogenization mixing and stirring of ultra-fine particle size tailings and high content, large particle size coarse aggregate, ensuring the homogeneity of the paste slurry and improving the integrity of the filling body.

[0059] The filling pipeline system adopts a high-pressure full-pipe delivery mode, which can reduce the working pressure of the filling plunger pump, reduce the vertical pipe pressure, and increase the delivery speed of the paste slurry. The horizontal pipeline uses nano-composite wear-resistant pipes, which effectively reduces pipe resistance, improves pipe pressure bearing capacity, ensures stable and safe delivery of slurry, and makes full use of deep well delivery conditions to achieve efficient and stable delivery of paste slurry under high flow and long distance conditions.

[0060] The entire filling process system is equipped with an intelligent control system, with real-time feedback and interconnection of operating data from various subsystems. The system performs intelligent dynamic adjustment and control according to design objectives, avoiding accidents caused by human operation and ensuring the stable operation of the complex filling process system.

[0061] In summary, this invention can solve the technical problems of paste filling under complex filling conditions, ensure the stable operation of the filling system, achieve high-quality filling, and provide a new approach for filling under such complex conditions. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 This is a schematic diagram of the system architecture for a solid waste paste filling process suitable for complex working conditions according to the present invention;

[0064] Figure 2 This is a schematic diagram of a solid waste paste filling process system applicable to complex working conditions according to the present invention.

[0065] The annotations in the attached figures are explained as follows:

[0066] 1-Industrial water supply system; 2-Electrically controlled valves; 3-Flocculant preparation system; 4-Static mixer; 5-Overflow tank; 6-Electrically controlled centrifugal pump; 7-Waste rock dump; 8-Waste rock receiving bin; 9-Belt conveyor; 10-Cement silo; 11-Double-body separator wheel; 12-Micro powder scale; 13-Cement truck; 14-Two-stage twin-shaft horizontal mixer; 15-Filling plunger pump; 16-Goaf; 17-Tailgating plant tailings conveying station; 18-Deep cone thickener; 19 20-Underflow high-level circulation pipeline; 21-Underflow low-level circulation pipeline; 22-Electrically controlled variable frequency slurry pump; 23-Concentration meter; 24-Flow meter; 25-Underflow thickening pipeline; 26-Spray water supply pipeline; 27-Agitation thickening pipeline; 28-Waste rock stabilizing silo; 29-Quantitative feeder; 30-Screw conveyor; 31-Spray dust suppression system; 32-Single-stage twin-shaft horizontal mixer; 33-Filling pipeline system; 34-Central feed cylinder. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0068] This invention provides a complete solid waste paste filling process system suitable for complex working conditions.

[0069] like Figure 1 The present invention provides a solid waste paste filling process system suitable for complex working conditions, including a tailings thickening system, a water collection and thickening system, a waste rock addition system, a cementitious material addition system, a paste mixing system, and a pump-pressurized pipeline transportation system. The above systems are interconnected and controlled by an intelligent control system.

[0070] The tailings thickening system includes a flocculant preparation system 3, a deep cone thickener 18, an underflow discharge pipeline 25, an underflow low-level circulation pipeline 20, and an underflow high-level circulation pipeline 19.

[0071] The water collection and concentration system includes an overflow tank 5, a bottom flow concentration pipeline 24, a stirring concentration pipeline 27, and a spray water supply pipeline 26;

[0072] The waste rock addition system includes a waste rock receiving bin 8, a belt conveyor 9, a waste rock stabilizing bin 28, and a quantitative feeder 29;

[0073] The cementitious material addition system includes a cementitious material silo 10, a double-body separator wheel 11, a micro powder scale 12, and a screw conveyor 30;

[0074] The paste mixing system includes a spray dust suppression system 31, a primary twin-shaft horizontal mixer 32, and a secondary twin-shaft horizontal mixer 14;

[0075] The pump-pressurized pipeline system includes a filling plunger pump 15 and a filling pipeline system 33;

[0076] The intelligent control system includes intelligent control software, electrically controlled valve 2, electrically controlled centrifugal pump 6, electrically controlled variable frequency slurry pump 21, concentration meter 22, and flow meter 23;

[0077] like Figure 2 The industrial water supply system is connected to the flocculant preparation system 3 and the static mixer 4 through pipelines, and each connecting pipeline is equipped with an electrically controlled valve 2.

[0078] The flocculant preparation system 3 is connected to the static mixer 4 via an electrically controlled centrifugal pump 6. The static mixer 4 is connected to the central feed cylinder 34 via a pipeline. The central feed cylinder 34 is located at the upper center of the deep cone thickener 18.

[0079] The tailings conveying station 17 of the concentrator is connected to the central feed cylinder 34 via a pipeline;

[0080] The overflow from the top of the deep cone thickener 18 is transported to the overflow tank 5 through a pipeline. The bottom of the overflow tank 5 is connected to the deep cone thickener 18 and the bottom flow thickening pipeline 24 through the electrically controlled centrifugal pump 6.

[0081] An electrically controlled valve is installed near the overflow tank 5 in the pipeline between the overflow tank 5 and the deep cone thickener 18. After the electrically controlled valve, the pipeline is divided into two branches. One branch is connected to the bottom of the deep cone thickener through an electrically controlled variable frequency slurry pump and an electrically controlled valve. The other branch is equipped with a concentration meter. After the concentration meter, it is connected to the underflow high-level circulation pipeline 19 and the underflow low-level circulation pipeline 20 of the deep cone thickener through electrically controlled valves, respectively.

[0082] The underflow concentration line 24 is divided into two branches. One branch is connected to the spray water supply line 26 and the stirring concentration line 27 respectively after passing through a flow meter. The other branch is connected to the underflow discharge line 25 through an electrically controlled valve.

[0083] The underflow discharge line 25 is led out from the bottom of the deep cone thickener 28. An electrically controlled valve and an electrically controlled variable frequency slurry pump 21 are installed near the bottom of the deep cone thickener 18. A branch of the underflow thickening line 24 merges into the pipeline after the electrically controlled variable frequency slurry pump 21. A concentration meter 22, a flow meter 34 and an electrically controlled valve are installed on the pipeline after the electrically controlled variable frequency slurry pump 21.

[0084] The underflow discharge line 25 and the stirring and thickening line 27 converge into the first-stage twin-shaft horizontal mixer 32, and the spray water supply line 26 is connected to the spray dust suppression system 31 on the upper part of the first-stage twin-shaft horizontal mixer 32;

[0085] Waste rock in waste rock dump 7 is transported to waste rock receiving bin 8. Waste rock receiving bin 8 is connected to waste rock stabilizing bin 28 via belt conveyor 9. Waste rock stabilizing bin 28 feeds waste rock into primary twin-shaft horizontal mixer 32 via quantitative feeder 29.

[0086] The material in the cement truck 13 is transported to the cementitious silo 10 through a pipeline. The cementitious silo 10 feeds the material to the screw conveyor 30 through the micro powder scale 12. The screw conveyor 30 then sends the material to the first-stage twin-shaft horizontal mixer 32.

[0087] The primary twin-shaft horizontal mixer 32 is connected to the secondary twin-shaft horizontal mixer 14. The secondary twin-shaft horizontal mixer 14 is connected to the filling pipeline system 33 through the filling plunger pump 15. The filling pipeline system 33 is connected to the goaf 16.

[0088] The bottom of the cementitious silo 10 is equipped with a double-body partition wheel 11.

[0089] A flow meter 23 and a concentration meter 22 are installed on the connecting pipe between the filling plunger pump 15 and the filling pipeline system 33.

[0090] The mixing blades of the single-stage twin-shaft horizontal mixer are continuous double-helix blades.

[0091] The mixing blades of the two-stage twin-shaft horizontal mixer are four-phase paddle blades plus continuous single-helix blades.

[0092] In a filling piping system, the diameter of the vertical pipe is greater than that of the horizontal pipe.

[0093] The application process of this system is as follows:

[0094] An external industrial water supply system supplies flocculant preparation water and secondary dilution water to the flocculant preparation system.

[0095] The flocculant solution prepared by the flocculant preparation system is pumped out by an electrically controlled centrifugal pump, collected with secondary dilution water, and then mixed and diluted in a static mixer to obtain a flocculant solution of the designed target concentration. After that, it is fed into the central feed cylinder inside the deep cone thickener at multiple points.

[0096] The external tailings conveying station transports low-concentration tailings slurry through pipelines to the central feed cylinder inside the deep cone thickener. The low-concentration tailings slurry mixes and is released with the diluted flocculant solution within the central feed cylinder, then thickens and settles within the deep cone thickener cylinder, forming a high-concentration tailings sludge layer. Overflow water from the deep cone thickener is collected in an overflow tank for storage.

[0097] When only tailings are stored without backfilling, the underflow high-level circulation pipeline is opened based on the feedback data of the sludge pressure and rake torque of the deep cone thickener to activate the tailings in the sludge layer and avoid rake crushing accidents.

[0098] During the backfilling operation, the underflow low-level circulation pipeline is turned on to homogenize the tailings in the mud layer. Based on the feedback data from the concentration meter, the underflow concentration adjustment pipeline is turned on to adjust the underflow tailings to the design target concentration range.

[0099] After the concentration of the underflow tailings stabilizes, the underflow discharge pipeline is opened. The dry amount of the underflow tailings is calculated based on the feedback data from the concentration meter and flow meter. The opening of the electrically controlled valve and the operating frequency of the electrically controlled variable frequency slurry pump are adjusted by the intelligent control system to make the dry amount of the underflow tailings reach the design target value. The underflow tailings slurry is then precisely and quantitatively delivered to the paste mixing system.

[0100] The intelligent control system calculates the required concentration water flow rate based on the total water demand for preparing the paste slurry and the water content of the bottom tailings slurry, opens the mixing and concentration pipeline, and intelligently adjusts the opening of the electrically controlled valve and the operating frequency of the electrically controlled centrifugal pump according to the feedback data from the flow meter, so as to quantitatively deliver the mixing and concentration water to the paste mixing system.

[0101] The external waste rock dump supplies waste rock aggregate to the waste rock receiving silo. After screening and primary stabilization in the waste rock receiving silo, the waste rock is discharged and transferred by a belt conveyor to the waste rock stabilization silo for secondary stabilization. The waste rock is then evenly fed to the quantitative feeder, and the waste rock is accurately measured according to the designed feeding amount and transported to the paste mixing system.

[0102] External cement trucks load cement into the cementitious material silo, which stores and discharges the cementitious material. The cementitious material is then fed into a double-body partition wheel for stabilization and evenly discharged into a micro powder scale. The cementitious material is precisely measured according to the designed feed rate and then conveyed to a screw conveyor, and finally transferred to the paste mixing system.

[0103] While waste rock, cementitious material, bottom runoff tailings slurry, and mixing concentrate are fed into the primary twin-shaft horizontal mixer, the spray dust suppression system receives water from the spray water supply pipeline and sprays it onto the primary twin-shaft horizontal mixer. This controls the total water content of the slurry, suppresses dust from fine particles, reduces material loss, and ensures accurate material distribution.

[0104] The continuous double helical blades in the first-stage twin-shaft horizontal mixer shear and mix various materials, making them evenly dispersed, and then push the materials into the second-stage twin-shaft horizontal mixer.

[0105] The four-phase impeller blades and continuous single-spiral blades in the two-stage twin-shaft horizontal mixer lift large-diameter materials, shear and mix various materials, ensure uniform dispersion of large-particle-size materials, homogenize and prepare paste slurry, and push the paste slurry to the pump-pressure pipeline transportation system.

[0106] The filling plunger pump provides power for conveying the paste slurry, and the concentration meter and flow meter monitor the state of the paste and the conveying parameters, and feed them back to the intelligent control system. The intelligent control system dynamically adjusts the operating parameters of each upstream process system in real time based on the feedback data to ensure that the final output paste slurry meets the design target requirements.

[0107] The paste slurry is transported to the underground goaf through the filling pipeline system.

[0108] The following description, in conjunction with specific embodiments, illustrates this point.

[0109] The parameters for complex operating conditions in the example are as follows:

[0110] Filling materials: extra-fine tailings, with -20μm content accounting for 45% and -74μm content accounting for 90%; -16mm continuously graded tunneling waste rock; reinforced fly ash cement.

[0111] Paste mixing parameters: tailings to waste rock ratio 4:6, paste concentration 77% to 79%, ash to aggregate ratio 1:4; slump of slurry 25 to 26.5 cm.

[0112] Filling capacity: 100-120m 3 / h.

[0113] Transportation conditions: vertical height difference 700m~800m, horizontal length 2.2~2.5km, three-stage borehole transfer.

[0114] The technical solution for the paste filling process system in this embodiment is as follows:

[0115] The main body of the paste filling process system consists of a tailings thickening system, a water collection and thickening system, a waste rock addition system, a cementitious material addition system, a paste mixing system, and a pump-pressure pipeline transportation system. The systems are interconnected and controlled by an intelligent control system.

[0116] P1. The tailings thickening system consists of a flocculant preparation system 3, a deep cone thickener 18, an underflow discharge pipeline 25, an underflow low-level circulation pipeline 20, and an underflow high-level circulation pipeline 19.

[0117] The deep cone thickener used has a diameter of 16m, a taper of 30°, a straight section height of 12m, and a cone height of 4m; the underflow discharge pipeline used has a production capacity of 0-80m³. 3 / h.

[0118] The flocculant preparation system is used to prepare flocculant solutions.

[0119] The deep cone thickener is used to thicken low-concentration tailings mortar, prepare and store high-concentration underflow tailings, and discharge overflow water.

[0120] The underflow discharge pipeline is used to discharge tailings from the deep cone thickener slurry, providing high-concentration tailings slurry to subsequent process stages.

[0121] The underflow low-level circulation pipeline is used to homogenize the tailings in the mud layer. It transports the tailings in the mud layer, whose concentration is distributed with height, to the upper part of the cone of the deep cone thickener for circulation, so as to homogenize the tailings in the mud layer and improve the uniformity and stability of the underflow tailings slurry concentration.

[0122] The underflow high-level circulation pipeline is used to activate the tailings slurry layer, and transport the high-concentration tailings slurry layer to the upper part of the deep cone thickener cylinder for circulation thickening, thereby reducing the slurry layer height, reducing the rake frame torque, and preventing rake crushing accidents.

[0123] P2. The water collection and concentration system consists of an overflow tank 25, a bottom flow concentration pipeline 24, a stirring concentration pipeline 27, and a spray water supply pipeline 26.

[0124] The overflow tank used has a volume of 96m³. 3 .

[0125] The overflow tank is used to collect and store the overflow water from the deep cone thickener.

[0126] The underflow thickening pipeline is used to adjust the underflow tailings concentration of the deep cone thickener. By introducing water from the overflow tank into the underflow discharge pipeline and the underflow low-level circulation pipeline, the high-concentration tailings are diluted with water to obtain the underflow tailings of the target concentration.

[0127] The stirring and thickening pipeline is used to output stirring and thickening water to subsequent process steps, so that the paste slurry reaches the designed target concentration.

[0128] The spray water supply pipeline branches off from the stirring and concentration pipeline to supply water to subsequent process stages.

[0129] P3. The waste rock addition system consists of a waste rock receiving bin 8, a belt conveyor 9, a waste rock stabilizing bin 28, and a quantitative feeder 29.

[0130] The waste rock receiving silo is rectangular, with an internal side length of 18m × 12m and a net height of 9.0m. The bottom features a double-eccentric quadrangular cone-shaped discharge hopper, with vibrators installed on the hopper walls. The waste rock stabilizing silo is rectangular, with an internal side length of 5m × 5m and a net height of 4.3m. The bottom also features a double-eccentric quadrangular cone-shaped discharge hopper, with vibrators installed on the hopper walls. The flow rate range of the quantitative feeder used is 0–100 m³ / h. 3 / h.

[0131] The waste rock receiving bin is used to load and screen waste rock, remove large pieces of uncrushed waste rock to avoid large pieces of waste rock affecting the operation of subsequent processes, and evenly feed the material to the belt conveyor for primary stable material output.

[0132] The belt conveyor is used to transfer waste rock to the waste rock silo.

[0133] The waste rock stabilization silo is used to load the waste rock after primary stabilization and to perform secondary stabilization of the waste rock, and to uniformly output the waste rock to the quantitative feeder.

[0134] The quantitative feeder is used to measure and transport waste rock, providing a quantitative input of waste rock for subsequent process steps.

[0135] P4. The cementitious material addition system consists of a cementitious material silo 10, a double-body separator wheel 11, a micro powder scale 12, and a screw conveyor 30.

[0136] The volume of the cementitious material silo used is 459m³. 3 The silo body is equipped with a silo wall vibrator at the conical part; the flow rate range of the micro powder scale used is 0-100 m³ / h. 3 / h.

[0137] The gelling silo is used to load and store gelling materials and to discharge them to the double-body separator wheel.

[0138] The dual-body separator wheel is used to stabilize the material and to evenly distribute it to the micro powder scale.

[0139] The micro powder scale is used for metering and conveying the cementitious material.

[0140] The screw conveyor is used to transfer the cementitious material, providing a quantitative input of cementitious material for subsequent process steps.

[0141] P5. The paste mixing system consists of a spray dust suppression system 31, a primary twin-shaft horizontal mixer 32, and a secondary twin-shaft horizontal mixer 14.

[0142] The production capacity of both the primary and secondary twin-shaft horizontal mixers used is 100-120 m³. 3 / h.

[0143] The spray dust suppression system is used to suppress dust in fine-particle materials fed into the primary twin-shaft horizontal mixer, control dust loss of each material, and improve the accuracy of material feeding.

[0144] The first-stage twin-shaft horizontal mixer has continuous double-helix blades for shearing and mixing the mixture, so that the various materials are evenly dispersed and pushed into the second-stage twin-shaft horizontal mixer.

[0145] The two-stage twin-shaft horizontal mixer has four-phase paddle blades plus continuous single-spiral blades for lifting large-particle materials, shearing and mixing various materials to ensure uniform dispersion of large-particle-size materials, achieving homogenized preparation of paste slurry, and pushing the paste slurry to subsequent process steps.

[0146] P6. The pump-pressure pipeline system consists of a filling plunger pump 15 and a filling pipeline system 33.

[0147] The filling plunger pump used has a production capacity of 0-140m³. 3 / h, maximum outlet pressure 11.5MPa; the filling pipeline system used has a vertical pipe inner diameter of 219mm and a horizontal pipe made of nano-polyurethane composite steel pipe with an inner diameter of 158mm.

[0148] The filling plunger pump is used to provide power for conveying paste slurry.

[0149] The filling pipeline system is used to transport paste slurry to a designated elevation and horizontal location underground.

[0150] P7. The automated control system consists of an intelligent control software system, remote control valves, and various monitoring instruments. It intervenes in the internal and inter-system links of each system, and performs mutual feedback adjustment on the real-time operating parameters of each system to achieve precise and intelligent control of the entire filling process.

[0151] Based on the components of the filling process system described in the above embodiments, the technical solution provided by the present invention has the following operational steps:

[0152] An external industrial water supply system supplies flocculant preparation water and secondary dilution water to the flocculant preparation system.

[0153] Furthermore, the flocculant solution prepared by the flocculant preparation system is pumped out by an electrically controlled centrifugal pump, collected with secondary dilution water, and then mixed and diluted in a static mixer to obtain a flocculant solution of the designed target concentration. After that, it is fed into the central feed cylinder inside the deep cone thickener at multiple points.

[0154] The external tailings conveying station transports 37±2% concentrated tailings slurry through pipelines to the central feed cylinder inside the deep cone thickener. The low-concentration tailings slurry mixes and is released with the diluted flocculant solution within the central feed cylinder, then thickens and settles within the deep cone thickener cylinder, forming a high-concentration tailings mud layer with a concentration of 55%–60%. Overflow water from the deep cone thickener is collected in an overflow tank for storage.

[0155] Furthermore, when only tailings are stored without backfilling, the underflow high-level circulation pipeline is opened based on the feedback data of the sludge pressure and rake torque of the deep cone thickener to activate the tailings in the sludge layer and avoid rake crushing accidents.

[0156] Furthermore, during the backfilling operation, the underflow low-level circulation pipeline is opened to homogenize the tailings in the mud layer. Based on the feedback data from the concentration meter, the underflow concentration adjustment pipeline is opened to adjust the underflow tailings to the design target concentration range.

[0157] Furthermore, after the concentration of the underflow tailings stabilizes, the underflow discharge pipeline is opened, and the dry amount of underflow tailings is calculated based on the feedback data from the concentration meter and flow meter. The opening degree of the electrically controlled valve and the operating frequency of the electrically controlled variable frequency slurry pump are adjusted by the intelligent control system to make the dry amount of underflow tailings reach the design target value, and the underflow tailings slurry is precisely and quantitatively delivered to the paste mixing system.

[0158] The intelligent control system calculates the required concentration water flow rate based on the total water demand for preparing the paste slurry and the water content of the bottom tailings slurry, opens the mixing and concentration pipeline, and intelligently adjusts the opening of the electrically controlled valve and the operating frequency of the electrically controlled centrifugal pump according to the feedback data from the flow meter, so as to quantitatively deliver the mixing and concentration water to the paste mixing system.

[0159] The external waste rock dump supplies waste rock aggregate to the waste rock receiving silo. After screening and primary stabilization in the waste rock receiving silo, the waste rock is discharged and transferred by a belt conveyor to the waste rock stabilization silo for secondary stabilization. The waste rock is then evenly fed to the quantitative feeder, and the waste rock is accurately measured according to the designed feeding amount and transported to the paste mixing system.

[0160] External cement trucks load cement into the cementitious material silo, which stores and discharges the cementitious material. The cementitious material is then fed into a double-body partition wheel for stabilization and evenly discharged into a micro powder scale. The cementitious material is precisely measured according to the designed feed rate and then conveyed to a screw conveyor, and finally transferred to the paste mixing system.

[0161] While waste rock, cementitious material, bottom runoff tailings slurry, and mixing concentrate are fed into the primary twin-shaft horizontal mixer, the spray dust suppression system receives water from the spray water supply pipeline and sprays it onto the primary twin-shaft horizontal mixer. This controls the total water content of the slurry, suppresses dust from fine particles, reduces material loss, and ensures accurate material distribution.

[0162] Furthermore, the continuous double helical blades in the first-stage twin-shaft horizontal mixer shear and mix various materials, ensuring uniform dispersion of the materials, and then push the materials into the second-stage twin-shaft horizontal mixer.

[0163] Furthermore, the four-phase impeller blades and continuous single-spiral blades in the two-stage twin-shaft horizontal mixer lift large-diameter materials, shear and mix various materials, ensure uniform dispersion of large-particle-size materials, homogenize and prepare paste slurry, and push the paste slurry to the pump-pressure pipeline transportation system.

[0164] The filling plunger pump provides power for conveying the paste slurry, and the concentration meter and flow meter monitor the state of the paste and the conveying parameters, and feed them back to the intelligent control system. The intelligent control system dynamically adjusts the operating parameters of each upstream process system in real time based on the feedback data to ensure that the final output paste slurry meets the design target requirements.

[0165] The paste slurry is transported to the underground goaf through the filling pipeline system.

[0166] The above description is merely an embodiment of the technical solution for a full solid waste paste backfilling process system suitable for complex working conditions proposed in this invention. This technical solution can solve the technical challenges of paste backfilling under complex backfilling conditions, achieving the homogenization preparation of pastes with high homogeneity, high strength, and complex material particle size composition, and their stable and efficient transportation under deep well, high flow, and long-distance working conditions, thereby improving the quality of mine backfilling and ensuring production safety.

[0167] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A full solid waste paste filling process system suitable for complex working conditions, characterized in that, It includes a tailings thickening system, a water collection and thickening system, a waste rock addition system, a cementitious material addition system, a paste mixing system, and a pump-pressure pipeline transportation system. The above systems are interconnected and controlled by an intelligent control system. The tailings thickening system includes a flocculant preparation system, a deep cone thickener, an underflow discharge pipeline, an underflow low-level circulation pipeline, and an underflow high-level circulation pipeline. The water collection and concentration system includes an overflow tank, a bottom flow concentration pipeline, a stirring concentration pipeline, and a spray water supply pipeline; The waste rock addition system includes a waste rock receiving bin, a belt conveyor, a waste rock stabilizing bin, and a quantitative feeder; The cementitious material addition system includes a cementitious material silo, a double-body separator wheel, a micro powder scale, and a screw conveyor. The paste mixing system includes a spray dust suppression system, a primary twin-shaft horizontal mixer, and a secondary twin-shaft horizontal mixer; The pump-pressurized pipeline system includes a filling plunger pump and a filling pipeline system; The intelligent control system includes intelligent control software, electrically controlled valves, electrically controlled centrifugal pumps, electrically controlled variable frequency slurry pumps, concentration meters, and flow meters; The industrial water supply system is connected to the flocculant preparation system and the static mixer via pipelines, and electrically controlled valves are installed on the connecting pipelines. The flocculant preparation system is connected to a static mixer via an electrically controlled centrifugal pump. The static mixer is connected to a central feed cylinder via a pipeline. The central feed cylinder is located at the upper center of the deep cone thickener. The tailings conveying station of the concentrator is connected to the central feed cylinder via pipeline; The overflow from the top of the deep cone thickener is transported to the overflow tank through a pipeline, and the bottom of the overflow tank is connected to the deep cone thickener and the underflow thickening pipeline through an electrically controlled centrifugal pump. An electrically controlled valve is installed near the overflow tank in the pipeline between the overflow tank and the deep cone thickener. After the electrically controlled valve, the pipeline splits into two branches. One branch is connected to the bottom of the deep cone thickener through an electrically controlled variable frequency slurry pump and an electrically controlled valve. The other branch is equipped with a concentration meter. After the concentration meter, the pipeline is connected to the underflow high-level circulation pipeline and the underflow low-level circulation pipeline of the deep cone thickener through electrically controlled valves. The underflow thickening pipeline is divided into two branches. One branch is connected to the spray water supply pipeline and the stirring thickening pipeline respectively after passing through a flow meter. The other branch is connected to the underflow discharge pipeline through an electrically controlled valve. The underflow discharge pipeline is led out from the bottom of the deep cone thickener. An electrically controlled valve and an electrically controlled variable frequency slurry pump are installed near the bottom of the deep cone thickener. A branch of the underflow thickening pipeline merges into the pipeline after the electrically controlled variable frequency slurry pump. A concentration meter, a flow meter and an electrically controlled valve are installed on the pipeline after the electrically controlled variable frequency slurry pump. The underflow discharge pipeline and the mixing and thickening pipeline converge into the first-stage twin-shaft horizontal mixer, and the spray water supply pipeline is connected to the spray dust suppression system at the top of the first-stage twin-shaft horizontal mixer; Waste rock in the waste rock dump is transported to the waste rock receiving bin, which is then connected to the waste rock stabilizing bin via a belt conveyor. The waste rock stabilizing bin feeds the waste rock into the primary twin-shaft horizontal mixer via a quantitative feeder. The material in the cement truck is transported to the cementitious silo through pipelines. The cementitious silo feeds the material to the screw conveyor through the micro powder scale. The screw conveyor then sends the material to the first-stage twin-shaft horizontal mixer. The first-stage twin-shaft horizontal mixer is connected to the second-stage twin-shaft horizontal mixer. The second-stage twin-shaft horizontal mixer is connected to the filling pipeline system via a filling plunger pump. The filling pipeline system is connected to the goaf. The mixing blades of the primary twin-shaft horizontal mixer are continuous double-helix blades; The mixing blades of the two-stage twin-shaft horizontal mixer are four-phase paddle blades plus continuous single-helix blades.

2. The full solid waste paste filling process system suitable for complex working conditions according to claim 1, characterized in that, The bottom of the gelling silo is equipped with a double-body partition wheel.

3. The full solid waste paste filling process system suitable for complex working conditions according to claim 1, characterized in that, A flow meter and a concentration meter are installed on the connecting pipe between the filling plunger pump and the filling pipeline system.

4. The full solid waste paste filling process system suitable for complex working conditions according to claim 1, characterized in that, In the filling pipeline system, the diameter of the vertical pipe is greater than the diameter of the horizontal pipe.

5. The all-solid-waste paste filling process system suitable for complex working conditions according to claim 4, characterized in that, The horizontal pipes in the filling pipeline system are nanocomposite wear-resistant pipes.

6. The all-solid waste paste filling process system suitable for complex working conditions according to claim 1, characterized in that, The underflow high-level circulation pipeline is located on one side of the upper part of the deep cone thickener cylinder, and its position is lower than the central feed cylinder; the underflow low-level circulation pipeline is located on one side of the upper part of the deep cone thickener cone, and its position is higher than the deep cone thickener cone.

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