Full-tailing efficient grading, concentrating and filling system

Abstract

The utility model relates to a full-tailing efficient grading, concentrating and filling system which comprises a full-tailing conveying pipe, tailing grading equipment, a coarse-fraction gravity settling sand bin, a fine-fraction flocculation settling sand bin, stirring equipment and a filling pump set. A coarse grain outlet of the tailing grading equipment is connected with an inlet of the coarse grain grade gravity settling sand bin through a pipeline, a fine grain tailing outlet of the tailing grading equipment is connected with an inlet of the fine grain grade flocculation settling sand bin through a pipeline, and an outlet of the coarse grain grade gravity settling sand bin and an outlet of the fine grain grade flocculation settling sand bin are connected with an inner cavity of the stirring equipment through pipelines respectively. A discharge hole of the stirring equipment is connected with an inlet of the filling pump set through a pipeline. The device has the advantages that the problems of low concentration efficiency, graded sedimentation and the like are well solved by adopting graded concentration of coarse and fine tailings, the dosage of a flocculating agent is reduced, the concentration speed and efficiency of the whole tailings are improved, the concentration efficiency is high, and the equipment configuration cost is low.

Description

Technical Field

[0001] The utility model relates to the technical field of underground goaf filling, in particular to a full tailings efficient graded concentrated filling system. Background Art

[0002] The backfill mining method has evolved from the initial dry backfill to water-sand backfill without gelling agent, and then to cemented backfill, and the backfill concentration has been continuously improved. Now it has developed into high-concentration backfill of full tailings and paste backfill. The current full tailings dehydration process mostly uses a deep cone thickener or a vertical sand bin using wind and water slurry making technology to directly prepare the full tailings into a high-concentration mortar, which is then mixed and stirred with a gelling agent and transported to the underground goaf. Because the full tailings dehydration and backfill slurry preparation and transportation are relatively convenient, it has become the most commonly used backfilling process in mines in my country.

[0003] Whole tailings is a non-uniform group of particles with a wide range of particle sizes. The "bridging effect" of polymer flocculants is generally aimed at tailings particles with finer particle sizes. When the tailings particle size increases to a certain value, it is difficult to participate in bridging. Studies have shown that when the particle size is greater than 0.03mm, there is almost no bridging effect. When it is between 0.01 and 0.03mm, there is a bridging effect but it is very weak. Only in particles below 0.01mm will there be obvious bridging phenomenon. Therefore, it is generally believed that the limit size of the bridging effect is 0.01mm, that is, after the particle size exceeds 0.01mm, there is almost no flocculation force, no flocs will be generated, and it has no effect on improving the settling rate of tailings. For the convenience of analysis, the tailings particles that can participate in the "bridging effect" are called "fine" particles, and vice versa, they are called "coarse" particles. In the whole tailings slurry, the sinking speed of "coarse" particles depends on the degree to which their own gravity overcomes the viscous resistance and shape resistance. "Fine" particles are bridged with high molecular weight flocculants to form larger flocs, which are loosely structured and amorphous, interconnected but not very stable, with a lot of space and fine networks inside, containing a lot of liquid, so the specific gravity of the flocs is close to the liquid itself, so the sinking speed is relatively low. The sinking speeds of the two particles in the whole tailings slurry are different.

[0004] Based on the above principles, the whole tailings is classified into coarse and fine particle sizes, and different concentration methods are used for the coarse and fine particle sizes, which will not only improve the concentration efficiency but also effectively reduce the equipment manufacturing and operation and maintenance costs.

[0005] At present, the most widely used process in engineering is the deep cone thickener or vertical sand bin (with the help of wind and water slurry to fluidize the bottom flow) full tailings mixing flocculation and concentration process.

[0006] A filling system based on the whole tailings mixing flocculation and concentration process consists of at least one sand silo (deep cone thickener or vertical sand silo f), one cement silo g and corresponding mixing equipment h and other facilities (such as Figure 1As shown). Due to the use of the full tailings mixing and concentration process, that is, the coarse and fine tailings are mixed and concentrated in a vertical sand bin, there are disadvantages such as low concentration efficiency, obvious coarse and fine particle classification and sedimentation, and short filling effective working time. The specific disadvantages are as follows:

[0007] (1) Low tailings concentration efficiency. The whole tailings mixed flocculation concentration process includes two sedimentation modes: natural gravity sedimentation of coarse-grained tailings and flocculation and agglomeration sedimentation of fine-grained tailings, and the two sedimentation modes are carried out simultaneously. In the flocculation and agglomeration process of fine-grained tailings, the natural gravity sedimentation of coarse-grained tailings will inevitably interfere with and destroy the flocculation and agglomeration of fine-grained tailings, prolonging the flocculation and agglomeration process of fine-grained tailings, resulting in low tailings concentration efficiency and a long time for the formation of underflow concentration.

[0008] (2) The cost of tailings dewatering is high. The biggest cost of flocculation dewatering is the consumption of flocculants. For the whole tailings mixed flocculation concentration, the flocculant is tested and added according to the mass content of tailings in the unit tailings slurry. In fact, in the whole tailings flocculation sedimentation process, the role of the flocculant is only to capture the fine-grained tailings and form flocs. The coarse-grained tailings are naturally gravity-sedimented, and the flocculant has no effect on the sedimentation of the coarse-grained tailings. Therefore, adding flocculants based on the total mass content of tailings in the tailings slurry will only cause a great waste and increase the cost of flocculation dewatering.

[0009] (3) High power consumption for dehydration. The bottom flow formed by the whole tailings mixing flocculation and thickening process contains a large amount of coarse particles, which makes the bottom flow compaction density high and causes a large yield stress. The rake frame of the deep cone thickener needs to consume a large amount of power to overcome the yield stress of the bottom flow and rotate to achieve smooth sand release.

[0010] (4) The dewatering equipment has a complex structure and high manufacturing and maintenance costs. The drive mechanism and scraper rake driven by external power of the deep cone thickener account for more than 60% of the manufacturing cost of the deep cone thickener. Due to the complex structure of the equipment, the manufacturing and maintenance costs are high. Once the operation is poorly managed or the physical gradation of the tailings changes, there is also a risk of causing a rake crushing accident, which will have an adverse impact on normal production operations.

[0011] (5) It is difficult to adapt to the production arrangements of the mine. Generally, the operation of the concentrator is 24 hours a day, which requires the tailings dewatering system of the filling station to cooperate with the work of the concentrator to achieve 24 hours of continuous operation. However, the effective working time of the filling operation is relatively short, with a daily working time of only about 8 hours, accounting for only 30% of the entire cycle time. This requires the dewatering equipment to have sufficient sand storage function, while the inefficient underflow acquisition method and the large amount of sand storage require the volume of the deep cone thickener or vertical sand bin to be larger or a large number of sand bins or large thickeners and other equipment to be configured, which further increases the equipment manufacturing cost. Utility Model Content

[0012] The technical problem to be solved by the utility model is to provide a full tailings efficient graded concentration filling system, which effectively overcomes the defects of the prior art.

[0013] The technical solution of the utility model to solve the above technical problems is as follows:

[0014] A full tailings efficient grading, concentrating and filling system comprises a full tailings conveying pipe, tailings grading equipment, a coarse-grained gravity sedimentation sand bin, a fine-grained flocculation sedimentation sand bin, a stirring equipment and a filling pump group, wherein the full tailings conveying pipe is connected to the inlet of the tailings grading equipment, the coarse-grained tailings outlet of the tailings grading equipment is connected to the inlet of the coarse-grained gravity sedimentation sand bin via a pipeline, the fine-grained tailings outlet of the tailings grading equipment is connected to the inlet of the fine-grained flocculation sedimentation sand bin via a pipeline, the outlets of the coarse-grained gravity sedimentation sand bin and the fine-grained flocculation sedimentation sand bin are respectively connected to the inner cavity of the stirring equipment via pipelines, and the material outlet of the stirring equipment is connected to the inlet of the filling pump group via a pipeline.

[0015] On the basis of the above technical solution, the present invention can also be improved as follows.

[0016] Furthermore, the tailings classification equipment is a cyclone, the bottom flow port of the cyclone constitutes the coarse particle outlet, and the overflow port constitutes the fine particle tailings outlet.

[0017] Furthermore, the above-mentioned mixing equipment is a high-concentration mixing drum for mining.

[0018] Furthermore, the above-mentioned coarse-grained gravity sedimentation sand bin includes a cylindrical sedimentation sand bin body, the bottom of the above-mentioned sedimentation sand bin body is provided with a first bottom flow port, the above-mentioned first bottom flow port constitutes its outlet, the side end of the upper end of the above-mentioned sedimentation sand bin body is provided with a first overflow port, the outside of the side end is provided with a first overflow weir connected to the above-mentioned first overflow port, the bottom of the above-mentioned first overflow weir is connected with a first overflow pipe, the above-mentioned tailings grading equipment is installed at the upper end of the above-mentioned sedimentation sand bin body, and its coarse particle outlet extends into the interior of the above-mentioned sedimentation sand bin body through a pipeline.

[0019] Furthermore, the bottom end of the sedimentation sand bin body is set to be conical, and a plurality of first fluidized pulping nozzles connected to the inner cavity are evenly arranged on the conical surface of the bottom end.

[0020] Furthermore, the above-mentioned fine-grained flocculation and sedimentation sand bin includes a cylindrical flocculation sand bin main body, a central feeding barrel is provided in the middle of the upper end of the interior of the above-mentioned flocculation sand bin main body, and a discharge port is provided around the side wall of the lower end of the above-mentioned central feeding barrel, and a feeding pipe and a flocculant addition pipe connected to the inner cavity of the above-mentioned central feeding barrel are respectively installed on the upper end of the above-mentioned flocculation sand bin main body, and the above-mentioned feed pipe is connected to the fine-grained tailings outlet of the above-mentioned tailings grading equipment, and a second bottom flow port is provided at the bottom of the above-mentioned flocculation sand bin main body, and the above-mentioned second bottom flow port constitutes its outlet, and a second overflow port is provided at the side end of the upper end of the above-mentioned flocculation sand bin main body, and a second overflow weir connected to the above-mentioned second overflow port is provided outside the side end, and the bottom of the above-mentioned second overflow weir is connected to the second overflow port, and a second overflow pipe is connected to the bottom of the above-mentioned second overflow weir.

[0021] Furthermore, an annular diverter cone is installed inside the flocculation sand bin body corresponding to the lower part of the central feeding barrel.

[0022] Furthermore, the bottom end of the flocculation sand bin body is set to be conical, and a plurality of second fluidized pulping nozzles connected to the inner cavity are evenly arranged on the conical surface of the bottom.

[0023] The beneficial effects are: the graded concentration of coarse and fine tailings, compared with the traditional mixed concentration and filling process, has effectively solved the problems of low concentration efficiency and graded sedimentation, reduced the amount of flocculants used, and improved the speed and efficiency of the whole tailings concentration, with high concentration efficiency and low equipment configuration cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a conventional full tailings thickening and filling system involved in the utility model;

[0025] Figure 2 It is a schematic diagram of the full tailings high-efficiency graded concentration and filling system of the utility model;

[0026] Figure 3 It is a structural schematic diagram of a coarse-grained gravity sedimentation sand bin in the full tailings high-efficiency graded concentration and filling system of the utility model;

[0027] Figure 4 It is a structural schematic diagram of the fine-grained flocculation and sedimentation sand bin in the full tailings high-efficiency graded concentration and filling system of the utility model.

[0028] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0029] 1. Full tailings conveying pipe; 2. Tailings grading equipment; 3. Coarse-grained gravity sedimentation sand bin; 4. Fine-grained flocculation sedimentation sand bin; 5. Mixing equipment; 6. Filling pump group; 31. Sedimentation sand bin body; 32. First overflow weir; 33. First overflow pipe; 41. Flocculation sand bin body; 42. Central feeding barrel; 43. Feed pipe; 44. Flocculant addition pipe; 45. Second overflow weir; 46. Second overflow pipe; 47. Diverter cone; 421. Discharge port. DETAILED DESCRIPTION

[0030] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0031] Example 1

[0032] like Figure 2 , 3 As shown in Figure 4, the full tailings efficient grading, concentrating and filling system of this embodiment includes a full tailings conveying pipe 1, a tailings grading equipment 2, a coarse-grained gravity sedimentation sand bin 3, a fine-grained flocculation sedimentation sand bin 4, a stirring equipment 5 and a filling pump group 6. The above-mentioned full tailings conveying pipe 1 is connected to the inlet of the above-mentioned tailings grading equipment 2, the coarse-grained outlet of the above-mentioned tailings grading equipment 2 is connected to the inlet of the above-mentioned coarse-grained gravity sedimentation sand bin 3 through a pipeline, the fine-grained tailings outlet of the above-mentioned tailings grading equipment 2 is connected to the inlet of the above-mentioned fine-grained flocculation sedimentation sand bin 4 through a pipeline, the outlets of the above-mentioned coarse-grained gravity sedimentation sand bin 3 and the fine-grained flocculation sedimentation sand bin 4 are respectively connected to the inner cavity of the above-mentioned stirring equipment 5 through pipelines, and the material outlet of the above-mentioned stirring equipment 5 is connected to the inlet of the above-mentioned filling pump group 6 through a pipeline.

[0033] In this embodiment, the whole tailings from the concentrator first enter the tailings classification equipment 2 for classification, and the coarser-grained underflow enters the coarse-grained gravity sedimentation sand bin 3 for natural gravity sedimentation; the finer-grained overflow enters the fine-grained flocculation sedimentation sand bin 4 for flocculation compression sedimentation (its concentration concentration and speed should match the coarse tailings); then, the high-concentration underflows of the two sand bins are simultaneously sent to the mixing equipment 5, and after being mixed with the gelling agent according to the specified lime-sand ratio, a qualified high-concentration filling slurry is prepared. Since this process adopts the classification and concentration of coarse and fine tailings, compared with the traditional mixed concentration filling process, it solves the problems of low concentration efficiency and classification sedimentation, and the specific advantages are as follows:

[0034] 1) Reduce the amount of flocculant used and improve the speed and efficiency of the whole tailings concentration. After the whole tailings are classified, the coarse-grained tailings are first subjected to natural gravity sedimentation in the coarse-grained gravity sedimentation sand bin 3, and the overflow of fine-grained tailings is sent to the fine-grained flocculation sedimentation sand bin 4, where flocculants are added for flocculation and concentration. On the one hand, since the flocculant is only used for the concentration of fine-grained tailings, the amount of flocculant used is reduced, and the concentration cost of the whole tailings slurry is reduced; on the other hand, the overflow fine-grained tailings has a concentration of only 5% to 7% after classification, which is within the optimal use range of the flocculant, thereby improving the speed and efficiency of the fine-grained tailings concentration and effectively reducing the amount and cost of flocculant addition.

[0035] 2) High concentration efficiency. For coarse-grained tailings, the natural gravity sedimentation speed is accelerated due to the absence of the influence and interference of the flocculation and agglomeration of fine-grained tailings, which improves the sedimentation rate; and the flocculation and agglomeration process of fine-grained tailings is also accelerated due to the absence of the influence and interference of the natural gravity sedimentation of coarse-grained tailings, which effectively improves the sedimentation rate.

[0036] 3) It can better adapt to the production arrangement of the mine. When configuring the two types of sand bins, as long as the incoming material volume of the 24-hour operation of the concentrator is fully considered, the effective volume of the sand bin is appropriately increased to make it have a certain sand storage function, it can adapt to the 24-hour continuous operation of the concentrator, and all the tailings can be concentrated through the sand bin. Increasing the effective volume of the sand bin not only has a very low manufacturing cost, but also has a better guarantee for the stability of the bottom flow concentration of the tailings.

[0037] In this embodiment, the tailings grading equipment 2 adopts a special equipment in the existing mining industry: a cyclone. In actual use, an appropriate cyclone model can be selected according to the particle size of the ore. The bottom flow port of the cyclone constitutes the coarse particle outlet, and its overflow port constitutes the fine particle tailings outlet.

[0038] The stirring device 5 is a high-concentration stirring drum for mining.

[0039] As a preferred embodiment, Figure 3 As shown, the coarse-grained gravity sedimentation sand bin 3 includes a cylindrical sedimentation sand bin body 31, a first bottom flow outlet is provided at the bottom of the sedimentation sand bin body 31, and the first bottom flow outlet constitutes its outlet. An annular first overflow weir 32 is provided at the port at the upper end of the sedimentation sand bin body 31, and a first overflow pipe 33 is connected to the lower part of the first overflow weir 32. The tailings grading equipment 2 is installed at the upper end of the sedimentation sand bin body 31, and its coarse particle outlet extends into the interior of the sedimentation sand bin body 31 through a pipeline.

[0040] In the above embodiment, the lower end of the sedimentation sand bin body 31 is configured with an adaptive frame so that its bottom is suspended in the air. The entire body adopts a simple silo, which has low manufacturing and maintenance costs. During the sedimentation and concentration process, the bottom flow of the sedimentation sand bin body 31 is sent to the stirring equipment 5.

[0041] As a preferred embodiment, the bottom end of the sedimentation sand bin body 31 is set to be conical, and a plurality of first fluidized pulping nozzles (denoted by a in the figure) connected to the inner cavity are evenly arranged on the conical surface of the bottom end.

[0042] In the above-mentioned implementation scheme, the purpose of the first fluidized slurrying nozzle is: with the help of a simple "pressure-controlled flow-assisted" wind and water slurrying method, it is easy to fluidize the coarse-grained sand accumulated in the sedimentation sand bin main body 31 to release the sand (to ensure that the local tailings at the bottom of the bin are fluidized during the initial sand release), so there is no need to set up other complex and costly scraper rakes; its manufacturing and maintenance costs are low, there is no risk of rake pressure, and there is no special equipment maintenance workload.

[0043] It should be noted that the function of the coarse-grained gravity sedimentation sand bin 3 is to receive and store the bottom flow slurry of the tailings classification equipment 2 (i.e., the hydrocyclone), so that the coarse-grained sand bin naturally settles by gravity to form a high-concentration mud layer, and the overflowing clarified water can be discharged to the reservoir or returned to the concentrator for reuse through the first overflow weir 32 on the upper part of the coarse-grained gravity sedimentation sand bin 3. The coarse-grained gravity sedimentation sand bin 3 does not require a special structure, and adopts a cylindrical silo structure with a hydrocyclone on top. In order to facilitate sand release, the lower part of the sand bin can be set into a cone shape (easy to release sand, the angle of the bottom cone is about 70°), and a plurality of first fluidized slurry nozzles are arranged on the lower cone in an annular interval to ensure that the local tailings at the bottom of the bin are fluidized during the initial sand release. When the sand can be successfully released, because the tailings fluidized layer has formed the inertia of sliding down at the bottom of the bin, turning off the second fluidized slurry nozzle at this time can not only achieve smooth sand release, but also ensure the stability of the bottom flow sand concentration. In order to further realize rapid sand release, the bottom cone angle of the coarse-grained gravity settling sand bin 3 is set to be smaller than the repose angle of the target bottom flow in terms of structure, so as to realize smooth sand release by relying on the gravity self-flowing effect of the material flow.

[0044] As a preferred embodiment, Figure 4As shown, the above-mentioned fine-grained flocculation and sedimentation sand bin 4 includes a cylindrical flocculation sand bin body 41, a central feeding barrel 42 is provided in the middle of the upper end of the above-mentioned flocculation sand bin body 41, and a discharge port 421 is provided around the lower end side wall of the above-mentioned central feeding barrel 42, and a feeding pipe 43 and a flocculant addition pipe 44 connected to the inner cavity of the above-mentioned central feeding barrel 42 are respectively installed at the upper end of the above-mentioned flocculation sand bin body 41, and the above-mentioned feeding pipe 43 is connected to the fine-grained tailings outlet of the above-mentioned tailings grading equipment 2, and a second bottom flow port is provided at the bottom of the above-mentioned flocculation sand bin body 41, and the above-mentioned second bottom flow port constitutes its outlet, and an annular second overflow weir 45 is provided at the fracture of the upper end of the above-mentioned flocculation sand bin body 41, and the lower part of the above-mentioned second overflow weir 45 is connected to the second overflow pipe 46.

[0045] In the above-mentioned implementation scheme, flocculants are added into the flocculation sand bin body 41 to react with the fine-grained tailings to achieve flocculation and agglomeration, forming floccules with a certain mass, which are then concentrated and settled in the bin body. Generally, a matching frame is configured at the lower end of the flocculation sand bin body 41 so that its bottom is suspended in the air, and the upper end of the central feeding barrel 42 is fixed on the frame. The entire flocculation sand bin body 41 adopts a simple silo, and its manufacturing and maintenance costs are relatively low.

[0046] In this embodiment, the flocculation and concentration of fine-grained tailings is a difficult point in the implementation of high-concentration filling of all tailings. Therefore, the development of a sand bin for flocculation and concentration of fine-grained tailings is the key to the smooth implementation of this process. Under the premise that other influencing parameters are fixed for the tailings processing capacity of the sand bin type flocculation and dehydration equipment, ① its tailings processing capacity depends on the sedimentation area, that is, the pool area of ​​the sand bin; ② the length and time of the compression sedimentation path during the flocculation and dehydration process determine the concentration of the bottom flow, that is, it depends on the height of the sand bin. The above two points are the basic principles and common sense of bin-type flocculation and dehydration equipment. Therefore, the upper cavity diameter of the flocculation sand bin main body 41 is designed to be larger than the diameter of the lower cavity. In the structural design of the flocculation and sedimentation sand bin, technical measures such as increasing the flocculation and sedimentation area and increasing the height of the mud layer in the compression and sedimentation section are adopted, which can effectively increase the processing capacity of tailings and increase the bottom flow concentration. Specifically, the upper large-diameter cavity of the flocculation sand bin body 41 draws on the structure of the traditional high-efficiency thickener flocculation tank and the vertical sand bin, and is grafted to form a large-diameter shallow bin with flocculant feeding and mixing barrels on the upper part - the flocculation and agglomeration bin (indicated by b in the figure), and a smaller-diameter cylindrical flocculation and agglomeration sedimentation and compression bin - the concentration bin (indicated by c in the figure) on the lower part. The bottom plate of the second overflow weir 45 is provided with a certain convergence slope at the interface with the second overflow pipe 46; a central feeding barrel 42 with a sealed bottom is provided in the middle of the flocculation and agglomeration bin, and a plurality of evenly spaced annular discharge ports 421 are provided on the side wall of the central feeding barrel 42 for the tailings slurry therein to flow horizontally into the flocculation and agglomeration bin. The purpose of such arrangement is to increase the mixing time of the tailings slurry and the flocculant so as to obtain sufficient mixing; an annular diverter cone 47 is installed inside the flocculation sand bin body 41 corresponding to the bottom of the above-mentioned central feeding barrel 42, so that the fine-grained tailings mixed with the flocculant are evenly distributed to the inside and outside of the thickening bin cavity through the annular diverter cone 47, so as to increase the flocculation and sedimentation area and obtain a better flocculation and agglomeration environment.

[0047] In this embodiment, in order to dilute the fine-grained tailings slurry with a higher concentration so that it can better combine with the flocculant, a plurality of square holes for supernatant feeding (indicated by e in the figure) are arranged around the upper part of the central feeding barrel 42. The liquid level difference caused by the density difference between the slurry and the supernatant inside and outside the central feeding barrel 42 is used to make the supernatant overflow into the central feeding barrel 42. The amount of dilution water will adjust itself with the fluctuation of the feed concentration, so that the slurry concentration inside the central feeding barrel 42 is always maintained within the optimal concentration and sedimentation range. The amount of dilution water does not depend on the amount of feed slurry, but only on the feed concentration: when the feed concentration is high, the amount of dilution water is larger; otherwise, the amount of dilution water is smaller. Through this structure, the slurry concentration in the feeding well is relatively stable, the feeding amount of flocculant is also relatively stable, and the consumption is minimal.

[0048] It should be additionally explained that the splitter cone 47 is annular in shape as a whole, and its longitudinal section is conical (with the tip facing upward).

[0049] The bottom end of the flocculation sand bin body 41 is set to be conical, and a plurality of second fluidized pulping nozzles (indicated by d in the figure) connected to its inner cavity are evenly arranged on the conical surface at the bottom.

[0050] In the above embodiment, the bottom conical design is conducive to sand release (in this embodiment, the angle of the bottom conical design of the flocculation sand bin body 41 is about 70°). In addition, since the bottom flow formed by flocculation and sedimentation in the flocculation and agglomeration bin has a low yield stress, the second fluidized pulping nozzle can be used to pass high-pressure wind or high-pressure water into the bottom of the flocculation sand bin body 41 to make it "fluidized pulping" during the initial sand release, so that the tailings at the bottom of the bin can be fluidized. When the sand can be successfully released, because the tailings fluidized layer has formed an inertia of downward flow at the bottom of the bin, turning off the second fluidized pulping nozzle can not only achieve smooth sand release, but also ensure the stability of the bottom flow sand concentration. In order to further achieve rapid sand release, the angle of the cone-shaped bin at the bottom of the concentration bin is also set to be smaller than the repose angle of the target bottom flow in terms of structure, and the smooth sand release is achieved by relying on the gravity self-flowing effect of the material flow. The overall structure does not need to be set with other complex and costly scraper rakes; its manufacturing and maintenance costs are low, there is no risk of pressure rakes, and there is no special equipment maintenance workload.

[0051] In this embodiment, the flocculation sand bin body 41 is designed with a flocculation and agglomeration bin with a diameter of 3.5m and a height of 2.5m at the top, a concentration bin with a diameter of 1.6m and a height of 5.0m at the bottom, a bottom cone angle of 70°, a total height of 8.7m and a volume of 32.8m. 3 The central feeding barrel 42 has a diameter of 1.2 m and a height of 1.5 m. The lower side wall of the central feeding barrel 42 is provided with 12 discharge ports 421, each of which is connected to a downwardly curved slurry discharge pipe, so that the tailing slurry in the sand inlet tube flows into the bin by itself.

[0052] In this embodiment, a bottom flow sand discharge pipe with a valve is installed at the outlet (second bottom flow outlet) at the bottom of the flocculation sand bin body 41, and a pressure sensor is installed on the sand discharge pipe for sand extraction test or L-shaped pipe self-flow multiple line test. A concentration meter, flow meter and pressure sensor are installed at the conical bottom of the thickening bin.

[0053] Example 2

[0054] A full tailings efficient graded thickening and filling process of this embodiment is implemented using the full tailings efficient graded thickening and filling system in Example 1, and includes the following steps:

[0055] Step 1: The whole tailings enters the tailings classification equipment 2 for classification to obtain coarse-grained whole tailings and fine-grained whole tailings;

[0056] Step 2: Send the coarse-grained full tailings into the coarse-grained gravity sedimentation sand bin 3 for natural gravity sedimentation to achieve natural gravity concentration. The overflow clarified water from the upper layer of the coarse-grained gravity sedimentation sand bin 3 can be discharged to the reservoir or returned to the concentrator for reuse through the first overflow weir 32 on the upper part of the coarse-grained gravity sedimentation sand bin 3. The overflow fine-grained tailings slurry of the tailings grading equipment 2 is sent to the fine-grained flocculation sedimentation sand bin 4 to achieve flocculation sedimentation concentration.

[0057] Step 3: Add flocculant to the fine-grained flocculation sedimentation sand bin 4 for flocculation and concentration to obtain a high-concentration fine-grained tailings slurry underflow;

[0058] Step 4: The coarse tailings bottom flow after gravity concentration in the coarse gravity sedimentation sand bin 3 and the fine tailings bottom flow after flocculation and concentration in the fine flocculation sedimentation sand bin 4 are respectively sent to the stirring device 5, and a gelling agent is added and stirred to obtain a high-concentration filling slurry;

[0059] Step 5: The high-concentration filling slurry mixed by the stirring device 5 is transported to the underground goaf area through the filling pump group 6 for filling.

[0060] The full tailings high-efficiency graded thickening and filling system of this embodiment was subjected to a semi-industrial test during the design process, as follows:

[0061] 1) A semi-industrial test was carried out using tailings from a lead-zinc ore concentrator. Before the semi-industrial test, the particle size composition characteristics of the whole tailings were tested, and it was found that the proportion of tailings particles of -0.01mm was about 14%, the proportion of tailings particles between +0.01 and -0.03mm was about 15%, and the proportion of tailings particles above +0.03mm was 71%. Therefore, most of the tailings particles are "coarse" particles, which mainly rely on their own gravity to settle in the whole tailings slurry; only 14% of the -0.01mm "fine" particle tailings gradually combine with the polymer flocculant molecules to form a flocculation group with a loose network structure; while the sedimentation rate of tailings particles between +0.01 and -0.03mm is significantly slower than that of tailings particles above +0.03mm, but this type of "coarse" particle tailings hits the flocculation group structure and is "netted", thereby driving the flocculation body to sink together. Therefore, this type of "coarse" particle tailings also has the effect of driving the flocculation group to accelerate the sedimentation.

[0062] Based on the above experiments and analysis, an attempt was made to determine the particle size classification interface as 0.037mm. The "coarse" sand with a particle size greater than 0.037mm in the tailings was separated to achieve natural gravity sedimentation; the "fine" particle tailings smaller than 0.01mm achieved flocculation sedimentation, and the tailings particles between 0.01 and 0.03mm served as the sedimentation kernel to drive the fine-grained flocculants to accelerate sedimentation.

[0063] 2) A fine-grained tailings flocculation and sedimentation test was conducted.

[0064] First, the -0.037 mm tailings were separated and prepared into a slurry with a concentration of 5% to 7%. The flocculant selection and flocculation sedimentation test were carried out in the laboratory using a measuring cylinder. The relative molecular weight of 1×10 7 Anionic polyacrylamide is used as flocculant; the flocculant concentration is 0.5‰; the flocculant consumption is 40g / t.

[0065] The quality of dry tailings processed per unit area in the fine-grained flocculation sedimentation sand bin 4 per unit time, i.e., the solid flux, comprehensively reflects the feed concentration and sedimentation rate.

[0066] 3) A full tailings classification and concentration test was conducted.

[0067] First, the whole tailings slurry (concentration 15% to 20%) enters the FX200-GX type grading cyclone (nominal separation particle size is 37 to 150 μm) for classification, and the bottom flow of the particle size above +0.037 mm enters the coarse-grained gravity sedimentation sand bin 3 for natural gravity sedimentation and concentration, and the fine-grained tailings overflow of -0.037 mm enters the fine-grained flocculation sedimentation sand bin 4 for flocculation sedimentation and concentration. Among them, the coarse-grained gravity sedimentation sand bin 3 conducts natural gravity sedimentation and concentration on the coarse-grained tailings above +0.037. In the coarse-grained gravity sedimentation sand bin 3, the coarse-grained tailings naturally sink and form a compaction layer, and the concentration gradually increases from top to bottom; the fine-grained tailings overflow with a concentration of 5% to 7% is pressurized by a pressure pump and transported to the fine-grained flocculation sedimentation sand bin 4 through a pipeline, and flocculation and concentration are carried out by adding flocculants. It should be pointed out that the purpose of pressurization is to make the fine-grained slurry entering the middle flocculation mixing barrel of the fine-grained flocculation sedimentation sand bin 4 have a certain fluid kinetic energy, so that it can rely on this kinetic energy to make tangential movement along the barrel wall in the flocculation mixing barrel, and fully mix with the flocculant through this movement. After 150 minutes, the tailings slurry overflowing from the coarse-grained gravity sedimentation sand bin 3 fills the entire flocculation sedimentation sand bin, and continues to discharge the tailings slurry into the fine-grained flocculation sedimentation sand bin 4, and the fine-grained flocculation sedimentation sand bin 4 begins to overflow. After 10 minutes, open the manual gate valve on the bottom flow pipe of the fine-grained flocculation sedimentation sand bin 4 to release the bottom flow. If there is a blockage problem at the beginning, the blockage can be eliminated by opening the second fluidized slurry nozzle to fluidize the compacted layer. The test shows that the bottom flow concentration of the vertical sand bin can reach 79%, and the slump is 15-20cm; the bottom flow concentration of the flocculation sedimentation sand bin can reach 54%, and the slump is 20-25cm. According to the ratio of coarse sand and fine sand to the total tailings, the underflows of the coarse-grained gravity sedimentation sand bin 3 and the fine-grained flocculation sedimentation sand bin 4 are quantified and enter the mixing equipment 5 together (in order to facilitate repeated verification in this test, no cement or gelling agent was added). The slurry concentration after mixing is 76%.

[0068] According to the above experimental research, the following application scope of the whole tailings classification and concentration process is obtained:

[0069] This process has been used to carry out semi-industrial concentration tests of multiple mine tailings, and the applicable scope of the whole tailings classification concentration process is summarized as follows:

[0070] 1. When the proportion of fine-grained tailings of -0.025 mm in the whole tailings is ≤36%, the graded concentration process can be used. This process can be used for tailings discharged by most domestic mine concentrators.

[0071] The area and structural dimensions of the upper flocculation and agglomeration bin of the fine-grained flocculation and sedimentation sand bin 4 are determined according to the fine-grained tailings flow rate, flocculation and sedimentation velocity, and the processing capacity based on engineering experience; the area and structural dimensions of the lower concentration bin are determined according to the tailings cover compression layer height, bottom flow concentration, slump, and flow rate.

[0072] When the proportion of fine tailings of -0.025 mm in the whole tailings is greater than 36%, the efficiency of the graded concentration process is not obvious due to the large amount of fine tailings. The fine-grained flocculation and sedimentation sand bin 4 can be directly used, and flocculants can be added for mixed sedimentation and concentration.

[0073] According to the above conclusions, compared with traditional similar equipment, under the condition of the same tailings treatment capacity, the whole tailings classification and concentration process has the characteristics of fast sedimentation rate and high concentration efficiency. The dehydration efficiency of the equipment system is increased by more than 2 times. Compared with the deep cone thickener, the investment is saved by about 30%, the energy consumption is reduced by about 70%, the amount of flocculant added is reduced by about 70%, and the operating cost is reduced by more than 30%. In the whole tailings classification and concentration process, the porosity of the bottom flow tailings accumulated in the coarse-grained gravity sedimentation sand bin 3 is higher, and its yield stress is smaller than that of the whole tailings; the tailings in the fine-grained flocculation sedimentation sand bin 4 have a lower concentration and a smaller yield stress, so there is no need for a large-power-driven scraper rake, and only the wind or water flow-assisted method is used to destroy its inertial yield stress when the sand is released to achieve smooth sand release.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-efficiency graded, concentrated and filled system for full tailings, characterized by: The invention comprises a full tailings conveying pipe (1), a tailings classification device (2), a coarse-grained gravity sedimentation sand bin (3), a fine-grained flocculation sedimentation sand bin (4), a stirring device (5) and a filling pump group (6), wherein the full tailings conveying pipe (1) is connected to the inlet of the tailings classification device (2), the coarse-grained tailings outlet of the tailings classification device (2) is connected to the inlet of the coarse-grained gravity sedimentation sand bin (3) through a pipeline, the fine-grained tailings outlet of the tailings classification device (2) is connected to the inlet of the fine-grained flocculation sedimentation sand bin (4) through a pipeline, and the outlets of the coarse-grained gravity sedimentation sand bin (3) and the fine-grained flocculation sedimentation sand bin (4) are respectively connected to the stirring device (6) through pipelines. 5) inner cavity, the material outlet of the stirring device (5) is connected to the inlet of the filling pump group (6) through a pipeline; the coarse-grained gravity sedimentation sand bin (3) comprises a cylindrical sedimentation sand bin body (31), the bottom of the sedimentation sand bin body (31) is provided with a first bottom flow port, the first bottom flow port constitutes its outlet, the upper end of the sedimentation sand bin body (31) is provided with an annular first overflow weir (32), the lower part of the first overflow weir (32) is connected to a first overflow pipe (33), the tailings grading equipment (2) is installed at the upper end of the sedimentation sand bin body (31), and its coarse-grained outlet extends into the interior of the sedimentation sand bin body (31) through a pipeline.

2. A full tailings efficient classification concentration filling system according to claim 1, characterized in that: The tailings classification equipment (2) is a cyclone, the underflow port of the cyclone constitutes the coarse-grained tailings outlet, and the overflow port constitutes the fine-grained tailings outlet.

3. The full tailings efficient classification concentration filling system according to claim 1 is characterized by: The stirring device (5) is a high-concentration stirring drum for mining.

4. The full tailings efficient classification concentration filling system according to claim 1 is characterized by: The bottom end of the sedimentation sand bin body (31) is set to be conical, and a plurality of first fluidized pulping nozzles connected to its inner cavity are evenly arranged on the conical surface of the bottom end.

5. The full tailings efficient classification concentration filling system according to claim 1 is characterized by: The fine-grained flocculation and sedimentation sand bin (4) comprises a cylindrical flocculation sand bin body (41), a central feeding barrel (42) is provided in the middle of the upper end of the flocculation sand bin body (41), a discharge port (421) is provided around the lower end side wall of the central feeding barrel (42), a feeding pipe (43) and a flocculant addition pipe (44) connected to the inner cavity of the central feeding barrel (42) are respectively installed at the upper end of the flocculation sand bin body (41), the feeding pipe (43) is connected to the fine-grained tailings outlet of the tailings grading equipment (2), a second bottom flow port is provided at the bottom of the flocculation sand bin body (41), and the second bottom flow port constitutes its outlet, and a ring-shaped second overflow weir (45) is provided at the port at the upper end of the flocculation sand bin body (41), and the lower part of the second overflow weir (45) is connected to the second overflow pipe (46).

6. A full tailings efficient classification concentration filling system according to claim 5, characterized in that: An annular flow dividing cone (47) is installed inside the flocculation sand bin body (41) and below the central feeding barrel (42).

7. The full tailings efficient classification concentration filling system according to claim 5 is characterized by: The bottom end of the flocculation sand bin body (41) is set to be conical, and a plurality of second fluidized pulping nozzles connected to its inner cavity are evenly arranged on the conical surface of the bottom.

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