Tailings-free mine's ultra-fine tailings treatment system and mine production system

Abstract

The application discloses a tailings-free mine fine tailings treatment system and mine production system, which comprises a thickener set, a conveying mechanism, a pretreatment mechanism and a monitoring feedback system, wherein the thickener set comprises a main treatment area and an adjusting area; at least one set of thickeners is arranged in the main treatment area; at least one set of thickeners is arranged in the adjusting area; the thickeners are used for buffering and concentrating input tailings; the conveying mechanism is used for conveying tailings; the pretreatment mechanism is respectively connected with the conveying mechanism and each thickener and is used for distributing tailings input by the conveying mechanism to each thickener; the monitoring feedback system is respectively arranged in the thickener set and the pretreatment mechanism and is used for monitoring the concentration and flow of incoming materials, the concentration state of tailings in each thickener and the concentration of discharged tailings; and the control system is respectively connected with the thickener set and the pretreatment mechanism and is used for controlling the communication state of the pretreatment mechanism and each thickener and adjusting the working state of each thickener.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mine tailings filling, in particular, to an ultra-fine tailings treatment system for tailings-free mines. In addition, the present application also relates to a mine production system comprising the above-mentioned ultra-fine tailings treatment system for tailings-free mines. BACKGROUND

[0002] Due to more stringent requirements for environmental protection and safety of mines, the total amount of tailings ponds is only decreasing, and it is almost impossible to newly build tailings ponds. At present, a large number of mines are facing the problem of depletion of the capacity of tailings ponds, i.e., in the future, a large number of mines will become tailings-free mines, and the treatment of tailings is a difficult problem. Therefore, the buffer storage of tailings flow will become more important, especially in mines where the extraction and filling can be balanced, tailings must be used for underground filling, and the buffer storage of tailings is the most important. In addition, the regional mineral resources in China are generally poor in their own endowments, and the raw ore grade is low. In order to more efficiently improve the beneficiation recovery rate and achieve efficient and green recovery, the ore must be ground finer to provide a better basis for beneficiation. Therefore, the tailings after beneficiation in domestic mines are generally fine, and there are many mines with ultra-fine tailings. In the process of filling underground or backfilling open pits, the conventional thickening equipment and process will face not small challenges in tailings concentration, paste preparation, and solidification. The disposal of ultra-fine tailings is difficult and the effect is poor. The current technical route for the disposal of ultra-fine tailings in tailings-free mines is usually to solidify and backfill in low-cost new and old goaf or open pit, and if there is any surplus, it can only be used for building material utilization.

[0003] In order to realize the low-cost solidification of ultra-fine tailings and improve the production organization and coordination ability of mines under the background of tailings-free mines, and realize the full utilization of tailings (i.e., underground filling or open pit backfilling), the key lies in the efficient concentration of ultra-fine tailings, the preparation of paste, the regulation and control of the system production of tailings-free mines, and the low-cost solidification. The conventional ultra-fine tailings paste preparation technology in the prior art mainly includes:

[0004] 1) Ultra-fine tailings pressure filtration + ultra-fine tailings thickening. Part of the incoming material of the beneficiation plant is thickened by an ordinary high-efficiency thickener and then pressure filtered into a filter cake (dehydrated to 70%), and the other part is thickened to a medium concentration (about 50%) by a conventional deep-cone thickener. Finally, the two parts of material are mixed and stirred to prepare a paste. If the production needs to be adjusted, the deep-cone thickener cannot be pressed with a rake, and all the tailings enter the pressure filtration system for pressure filtration. This process has many technical links, complex process, high investment and cost, and large occupied area.

[0005] 2) Ultra-fine tailings thickening + broken waste rock, pump the ultra-fine tailings into the deep cone thickener, concentrate to a certain concentration (usually 50%~55%) after entering the mixing system, the other end uses broken waste rock at the same time into the mixing system, and the two are mixed to prepare a paste. If the production needs to be adjusted, the deep cone thickener cannot be pressed, and a set of filter pressing system often needs to be built; this process often has large investment and cost, and the tailings treatment capacity is greatly reduced, and the land occupation area is large.

[0006] 3) Deep cone thickener + sand bin, pump the tailings into the deep cone thickener, concentrate all by the deep cone thickener, and fill the sand after concentrating into a paste. If the concentration decreases, stop filling the sand, and if the deep cone thickener is full, pump it to the sand bin for storage immediately without filling in the well, and the tailings in the sand bin are grouted and filled. The advantage of this way is that it does not need to build a filter pressing system, and the sand bin has a certain storage capacity, but its disadvantage is that the deep cone thickener has a raking frame, and there is a risk of raking behind, and the reliability is insufficient. In addition, the treatment capacity of the deep cone thickener is generally calculated as 0.5~0.7t / ㎡•h, the treatment efficiency of the ultra-fine tailings is low, the sand bin does not have the function of concentration, only the function of storage and small storage capacity, the tailings concentration method is single, all rely on the deep cone, the risk of overflow water running is large, and the production organization coordination ability is limited. SUMMARY

[0007] The present application provides an ultra-fine tailings treatment system for a tailings-free mine and a mine production system to solve the technical problems of high cost, large equipment land occupation area, poor storage capacity, and poor production quality stability in the prior art.

[0008] According to one aspect of the present application, an ultra-fine tailings treatment system for a tailings-free mine is provided, comprising:

[0009] A thickener set comprising a main treatment area and an adjustment area, the main treatment area being provided with at least one set of thickeners, and the adjustment area being provided with at least one set of thickeners, the thickeners being used to buffer and concentrate the input tailings;

[0010] A conveying mechanism for conveying tailings;

[0011] A pretreatment mechanism connected to the conveying mechanism and each of the thickeners, respectively, for distributing the tailings input by the conveying mechanism to each of the thickeners;

[0012] A monitoring feedback system provided in the thickener set and the pretreatment mechanism, respectively, for monitoring the concentration and flow of incoming materials, the concentration state of tailings in each of the thickeners, and the sanding concentration;

[0013] A control system is connected to the thickener group and the pretreatment mechanism respectively, and is used to control the communication state of the pretreatment mechanism and each thickener according to the concentration and flow of the incoming material, and is also used to adjust the working state of each thickener according to the concentration state of the tailings and the concentration of the discharged tailings.

[0014] As a further improvement of the above technical solution, the conveying mechanism is connected to the pretreatment mechanism through a conveying pipe, and the monitoring feedback system comprises a first flow monitoring unit and a first concentration monitoring unit arranged on the conveying pipe; the pretreatment mechanism comprises a distribution box arranged above the thickener group, the distribution box is connected to the conveying mechanism through the conveying pipe, the distribution box is connected to each thickener of the main treatment area through a branch pipe respectively, the number of branch pipes matches the number of thickeners in the main treatment area, or the distribution box is connected to each thickener through a branch pipe respectively, and the number of branch pipes matches the number of thickeners.

[0015] As a further improvement of the above technical solution, the discharge end of each thickener is connected to a stirring system through an output pipe respectively, the monitoring feedback system comprises a second flow monitoring unit and a second concentration monitoring unit arranged on each output pipe respectively; the control system comprises a direction changing mechanism arranged on the output pipe of the main treatment area, the direction changing mechanism is connected to the feed end of the thickener of the adjustment area, and the control system is used to control the communication between the discharge end of the thickener of the main treatment area and the feed end of the thickener of the adjustment area when the concentration of the discharged tailings in each thickener of the main treatment area is lower than a preset value.

[0016] As a further improvement of the above technical solution, the thickener of the adjustment area is provided with a stepped drainage mechanism, which is used to discharge excess water of the clear water layer in the thickener of the adjustment area when the discharge end of the main treatment area is communicated to the adjustment area, so as to match the height position of the clear water layer.

[0017] As a further improvement of the above technical solution, the ultra-fine tailings treatment system further comprises a dosing device, the dosing device is connected to the pretreatment mechanism and / or each thickener through a dosing pipe, the dosing device is used to add flocculating agent into the pretreatment mechanism through the dosing pipe to pre-mix the flocculating agent with the incoming material, and / or is used to add flocculating agent into the thickener to mix the flocculating agent with the incoming material.

[0018] As a further improvement of the above technical solution, the monitoring feedback system comprises a material level monitoring unit arranged on each thickener respectively, which is used to monitor the material level height in the thickener, and is used to control the material level height of each thickener to be kept between a critical low material level and a critical high material level respectively.

[0019] As a further improvement of the above technical solution, the material level monitoring unit comprises a pressure monitoring unit arranged at the bottom of the thickener for monitoring the slurry pressure and / or an ultrasonic detection unit arranged at the bottom of the thickener for monitoring the mud layer height.

[0020] As a further improvement of the above technical solution, the critical low material level is arranged at a range of 5-7 m above the bottom of the processing cavity of the thickener in the main processing area.

[0021] As a further improvement of the above technical solution, the height-diameter ratio in the processing cavity of the thickener is arranged to be 1.8-2.2.

[0022] According to another aspect of the present application, there is also provided a mine production system comprising the above-mentioned ultra-fine tailings processing system for tailings-free mines.

[0023] The present application has the following beneficial effects:

[0024] The system builds a thickener group based on the thickener, and respectively plans and lays out the main processing area and the adjustment area, the thickener in the main processing area is used for conventional tailings concentration and paste preparation, in the case of sudden increase of tailings, partial equipment failure of the main processing area, substandard processing concentration of the main processing area, further static storage, etc., the tailings are pumped to the adjustment area for further concentration treatment or static storage, which greatly improves the storage capacity, redundancy and stability of the system and effectively guarantees the concentration, further through the pre-treatment mechanism, the slurry pumped from the concentrator is energy dissipated, so that the slurry changes from turbulent flow to laminar flow, and the pre-treatment mechanism can distribute the incoming material, the concentration and flow of the incoming material are monitored based on the monitoring feedback system, and in the case of excessive amount or concentration of the incoming slurry, the incoming slurry can be distributed to multiple thickeners for concentration, so as to alleviate the difficulty of processing the tailings slurry by a single thickener, to ensure the overflow backwater clarification, and to match the production demand and reasonably control the energy consumption; the system can be applied to tailings-free mines, in the case that there is no tailings pond and the tailings need to be used for underground or open pit filling, the thickener group scheme and the control system based on the system are cooperatively controlled to realize the buffering, storage and adjustment of all tailings from the concentrator, so that the production of the ore dressing, filling, underground backfilling and other links of the mine is kept smooth, the tailings cannot be processed due to no underground filling, and the system can completely replace the traditional filter pressing system, reduce the equipment investment and land occupation, and greatly reduce the cost.

[0025] In addition to the purposes, features and advantages described above, the present application has other purposes, features and advantages. The present application will be further described below with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0026] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the application and, together with the description, serve to explain the application. In the drawings:

[0027] Figure 1 is a system structure diagram of a preferred embodiment of the present application.

[0028] Legend:

[0029] 1, conveying mechanism; 2, first flow monitoring unit; 3, first concentration monitoring unit; 4, conveying pipe; 5, distribution box; 6, dosing pipe; 7, branch pipe; 8, electric regulating valve; 9, central tank; 10, heavy weight level gauge; 11, main treatment area; 12, thickener; 13, regulating area; 14, pressure monitoring unit; 15, ultrasonic detection unit; 16, jet system; 17, critical high level; 18, critical low level; 19, second flow monitoring unit; 20, second concentration monitoring unit; 21, underflow pump; 22, direction changing mechanism; 23, stirring system; 24, stepped drainage mechanism; 25, screw pump; 26, dosing device; 27, circulation pipeline. DETAILED DESCRIPTION

[0030] The embodiments of the present application will be described in detail below with reference to the drawings, but the present application can be implemented in various different ways as defined and covered below.

[0031] Figure 1 is a system structure diagram of a preferred embodiment of the present application.

[0032] As shown in Figure 1 , the ultra-fine tailings treatment system for tailings-free mines of the present embodiment comprises:

[0033] a thickener set, comprising a main treatment area 11 and a regulating area 13, the main treatment area 11 being provided with at least one set of thickeners 12, and the regulating area 13 being provided with at least one set of thickeners 12, the thickeners 12 being used for buffering, thickening and / or storing the input tailings, and being used for;

[0034] a conveying mechanism 1 for conveying the tailings;

[0035] a pretreatment mechanism connected to the conveying mechanism 1 and each thickener 12 respectively, for distributing the tailings input by the conveying mechanism 1 to each thickener 12;

[0036] a monitoring feedback system provided in the thickener set and the pretreatment mechanism respectively, for monitoring the concentration of the incoming material, the flow of the incoming material, the thickening state of the tailings in each thickener 12 and the discharge concentration of the tailings;

[0037] The control system is connected with the thickener set and the pretreatment mechanism respectively, and is used for controlling the communication state of the pretreatment mechanism and each thickener 12 according to the concentration and flow of the incoming material, and is also used for adjusting the working state of each thickener 12 according to the concentration state of the tailings and the concentration of the discharged tailings.

[0038] The conveying mechanism 1 is a conveying pump, which conveys the tailings of the concentrator to the system. In the preferred embodiment, the parts of the mine production system, such as the conveying pump, which are not specifically described can be implemented by referring to the prior art. It should be noted that the processing system in the preferred embodiment is directly connected with the stirring system 23. The tailings are stored in the processing system after concentration treatment, and are directly output to the stirring system 23 for subsequent processes according to production requirements, so that the filter pressing system is cancelled or replaced.

[0039] It should be noted that at least two sets of thickeners are arranged in the main processing area in a medium or large mine, and one or more sets of thickeners are arranged in the adjustment area. In a small mine, one set of thickener can be arranged in the main processing area and the adjustment area respectively.

[0040] It can be understood that the conventional deep-cone thickener with a rake frame has limited storage capacity, and can only store for 8 hours under full storage conditions. Small volume and untimely discharge will cause a rake pressing accident, resulting in mine production stoppage. The system preferably uses the existing technology of the paste storage type thickener 12 without a rake frame to improve the storage capacity and static storage time of the system under full storage conditions.

[0041] The system is based on the paste storage type thickener 12 to build a thickener group, and respectively plans and lays the main treatment area 11 and the adjustment area 13. The thickener 12 of the main treatment area 11 is used for conventional tailings concentration and paste preparation. In the case of sudden increase of tailings, partial equipment failure of the main treatment area 11, substandard treatment concentration of the main treatment area 11, and further static storage, the tailings are pumped to the adjustment area 13 for further concentration treatment or static storage, which greatly improves the storage capacity, redundancy and stability of the system and effectively guarantees the concentration. Further, the pretreatment mechanism is set to perform energy dissipation on the slurry pumped from the concentrator, so that the slurry changes from turbulent flow to laminar flow. The pretreatment mechanism can distribute the incoming material. The concentration and flow of the incoming material are monitored based on the monitoring feedback system. When the amount or concentration of the incoming material is too large, the material can be distributed to multiple thickeners 12 for concentration, which can alleviate the difficulty of processing tailings slurry by a single thickener, so as to ensure overflow backwater clarification, match production demand, and reasonably control energy consumption. The system can be applied to a tailings-free mine. In the case that there is no tailings pond in the mine and all tailings need to be used for underground or open pit filling, the thickener group scheme and control system based on the system are used for collaborative control to realize the buffering, storage and adjustment of all tailings from the concentrator, so that the production of ore dressing, filling, underground backfill and other links of the mine remains smooth, the problem of tailings unable to be processed due to no underground filling is avoided, and the traditional filter pressing system can be completely replaced, the equipment investment and land area are reduced, and the cost is greatly reduced.

[0042] Further, in some embodiments, the height-diameter ratio of the processing cavity of the thickener 12 is set to 1.8-2.2; it should be noted that ultra-fine tailings generally refer to the content of-20 μm tailings particles being more than 50% or the average particle size D < 20 μm, which is referred to as extremely fine tailings, and the conventional thickener has a small tailings treatment capacity (0.3-0.5 t / m2•h), low efficiency, great difficulty in flocculation and sedimentation, great consumption of flocculants, and easy running mud; in order to have a better flocculation and concentration effect, the size of the deep-cone thickener selected is very large, and the investment and land occupation are large; after the flocculation and sedimentation of the extremely fine tailings particles, the flocculant molecular chain wraps the tailings particles to form flocs, and a large amount of water molecules are also wrapped, the wrapped water molecules are difficult to separate out in a short time, and finally a relatively loose slurry is formed in the thickener, resulting in low concentration. In addition, due to the structural design of the conventional deep-cone thickening equipment, the height of the vertical section side wall is generally 10 m, and due to the rake frame, the height of the mud layer formed by the tailings flocs generally cannot exceed 7 m, otherwise the rake is easily pressed, and the storage space and time of the tailings in the thickener are limited. The concentration gradient of the tailings slurry in the vertical direction in the thickener changes, and generally from bottom to top, it is divided into dense layer, compression layer, sedimentation layer, and clear water layer. Due to the inability to form a higher mud layer height, the concentration time of the tailings in the thickener is short and the water content of the flocs is large, the concentration of the bottom dense layer is generally difficult to meet the standard, and along with the sand discharge process, due to the imbalance of the tailings entering and discharging (less entering than discharging), the mud layer level drops, and the mud layer level itself is not high, and there is no enough buffer adjustment room, resulting in the mud layer height dropping to the compression layer in a short time, and finally the concentration is greatly reduced and the concentration fluctuates greatly; therefore, in the present embodiment, the thickener 12 without a rake frame is used to improve the system storage capacity and storage time; the height-diameter ratio of each type of thickener in the prior art is generally in the range of 1.2-1.6; based on the buffering, storage, and stability requirements of the preferred embodiment of the present application, and based on the rake-free structure of the thickener 12, the height-diameter ratio of the processing cavity of the thickener 12 is set to 1.8-2.2, the vertical height is increased, the extremely fine tailings have a high enough mud layer height and enough concentration time, the sedimentation of the tailings in the thickener is more sufficient, the concentration of the bottom dense layer meets the standard, the pulp quality is stable, and the balance destruction problem caused by the mud layer level drop during sand discharge is avoided, and the concentration is stable.

[0043] In some embodiments, the conveying mechanism 1 is connected with the pretreatment mechanism through the conveying pipe 4, the monitoring feedback system comprises the first flow monitoring unit 2 and the first concentration monitoring unit 3 arranged on the conveying pipe 4; the pretreatment mechanism comprises a distribution box 5 arranged above the thickener set, the distribution box 5 is connected with the conveying mechanism 1 through the conveying pipe 4, and the distribution box 5 is connected with each thickener 12 of the main treatment area 11 respectively through the branch pipe 7 and can be connected with the central barrel 9; the number of the branch pipes 7 matches the number of the thickeners 12 of the main treatment area 11, or the distribution box 5 is connected with each thickener 12 respectively through the branch pipe 7, and the number of the branch pipes 7 matches the number of the thickeners 12; preferably, the distribution box 5 is connected with each thickener 12 of the main treatment area 11 respectively through the branch pipe 7; according to the monitoring results of the first flow monitoring unit 2 and the first concentration monitoring unit 3, the control system controls the pulp distribution of the distribution box 5 to be distributed to one or more thickeners of the main treatment area 11 for thickening treatment, that is, only one thickener is started when one thickener can meet the use demand, two or more thickeners are started for treatment when the incoming flow is too large or the concentration is too large, thereby avoiding the problem that the processing capacity of a single thickener is limited, ensuring that the overflow water is clarified, and avoiding the application of the filter pressing system; on the other hand, the distribution box 5 can pump the tailings pulp of the system to dissipate energy, so that the pulp changes from turbulent flow to laminar flow, further improving the working capacity of the thickener and improving the stability in the cavity; in some embodiments, the control system comprises the electric regulating valve 8 arranged on each branch pipe 7 respectively, the opening degree and the on-off of the electric regulating valve 8 on each branch pipe 7 are controlled respectively according to the incoming flow and the concentration fed back by the first flow monitoring unit 2 and the first concentration monitoring unit 3, so as to realize intelligent distribution of the incoming material; in the embodiment in which the distribution box 5 is connected with the thickeners of the adjusting area 13 through the branch pipe 7, for the working conditions such as sudden increase of the tailings incoming material and partial equipment failure of the main treatment area 11, the tailings incoming material can be distributed to the thickeners of the adjusting area 13 through the distribution box 5 for treatment;

[0044] In some embodiments, the discharge end of each thickener 12 is connected to the stirring system 23 through an output pipe respectively, the monitoring feedback system comprises a second flow monitoring unit 19 and a second concentration monitoring unit 20 arranged on the output pipe respectively, and the control system comprises a reversing mechanism 22 arranged on the output pipe of the main treatment area 11, the reversing mechanism 22 being connected to the feed end of the thickener 12 of the adjusting area 13, and the control system being used to control the discharge end of the thickener 12 of the main treatment area 11 to communicate with the feed end of the thickener 12 of the adjusting area 13 when the sand discharge concentration in each thickener 12 of the main treatment area 11 is lower than the preset value; specifically, the control system controls the reversing mechanism 22 to act according to the output concentration and flow of the thickener of the main treatment area 11 fed back by the second flow monitoring unit 19 and the second concentration monitoring unit 20, so that the output slurry is further thickened to the thickener 12 of the adjusting area 13 through the reversing mechanism 22, effectively improving the storage capacity, redundancy, stability and concentration of the system, realizing complete replacement of the filter pressing system, and further reducing equipment investment and space occupation; on the other hand, the thickener of the main treatment area 11 can realize dynamic storage, and when static storage is needed, the tailings can be output to the adjusting area 13 for static storage, greatly improving the storage capacity of the system; it should be understood that the reversing mechanism 22 is preferably a three-way reversing valve arranged on the output pipe, one interface being connected to the stirring system 23 and the other interface being connected to the thickener of the adjusting area 13 through a circulating pipeline 27; other embodiments can use a reversing mechanism 22 with the same effect; preferably, the second flow monitoring unit 19 and the second concentration monitoring unit 20 are arranged on the output pipe and located between the reversing mechanism 22 and the discharge end of the corresponding thickener, so as to ensure that the reversing mechanism 22 has sufficient response time and avoid that the slurry with substandard concentration is output to the stirring system 23; further, the thickener 12 of the adjusting area 13 is provided with a stepped drainage mechanism 24 for draining the excess water in the clear water layer in the thickener 12 of the adjusting area 13 according to the height position of the clear water layer when the discharge end of the main treatment area 11 is communicated to the adjusting area 13; the stepped drainage mechanism 24 can be a drainage pipe designed step by step from the top of the thickener of the adjusting area 13 downward, and a drainage valve is arranged correspondingly to control the opening and closing of the drainage pipe, and the drainage valve at the height position matched with the detected height position of the clear water layer or all the drainage valves above the position are opened to drain the excess water in the supernatant; when the thickener of the main treatment area needs to input the slurry with substandard concentration or all the slurry to the thickener of the adjusting area, the slurry is unqualified paste and cannot be directly used for filling, and the excess water in the supernatant is drained through the stepped drainage mechanism to further improve the concentration before being supplied to the stirring system; on the other hand, when there is no filling underground and the thickener of the main treatment area reaches a high material level, the slurry is input to the adjusting area for further storage, greatly improving the storage capacity.

[0045] In some embodiments, the ultra-fine tailings treatment system further comprises a dosing device 26 connected to the pre-treatment mechanism and / or to each thickener 12 via the dosing pipe 6, the dosing device 26 being configured to add flocculants into the pre-treatment mechanism via the dosing pipe 6 to pre-mix the flocculants with the feed material, and / or to add flocculants to the thickener 12 to mix the flocculants with the feed material, preferably, the dosing device 26 is connected to the pre-treatment mechanism via the dosing pipe 6 to pre-mix the flocculants with the tailings slurry in advance, increasing the reaction time of the tailings with the flocculants, and combining more fully; in the present embodiment, the dosing device 26 is connected to both the pre-treatment mechanism and the thickener, and the dosing device 26 adds flocculants to both according to the requirements; the dosing device 26 controls the delivery flow rate through an adjustable delivery device such as a screw pump 25 to match the amount of flocculants added to the amount of feed material.

[0046] In some embodiments, the monitoring feedback system comprises a level monitoring unit arranged at each thickener 12, respectively, for monitoring the level height of the thickener 12, and for controlling the level height of each thickener 12 to be maintained between the critical low level 18 and the critical high level 17, the critical high level 17 being monitored by the weight level gauge 10, and when the current thickener slurry level reaches the critical high level 17, the feed material is stopped and processed by other thickeners, and when the current thickener slurry level reaches the critical low level 18, the discharge of the feed material is stopped and switched to other thickeners that meet the requirements, through the coordinated control and dynamic adjustment of the thickener group, the concentration and stability of the paste slurry are effectively ensured, the concentration fluctuations are avoided to cause equipment failure, and the unstable pulp quality is avoided; it can be understood that the control system controls the opening and closing of the electrically controlled regulating valve to control the feed of the thickener on the corresponding branch; the control system further comprises a underflow pump 21 arranged at the discharge end of each thickener for conveying the material at the discharge end;

[0047] Further, the level monitoring unit comprises a weight level gauge 10 arranged at the top of the thickener 12, and a pressure monitoring unit 14 arranged at the bottom for monitoring the pressure of the slurry, and / or an ultrasonic detection unit 15 arranged at the bottom of the thickener 12 for monitoring the height of the slurry, wherein the pressure monitoring unit 14 can be a pressure sensor, which detects the slurry pressure at the bottom to determine the height of the slurry, and the ultrasonic detection unit 15 can also be used to monitor the slurry, preferably an ultrasonic detector, which releases high-density high-frequency ultrasonic waves, and can obtain the thickness and distribution height of the dense layer, compression layer, settlement layer, and clear water layer based on the density distribution of the slurry feedback by the ultrasonic waves, which is more accurate than the pressure sensor monitoring, and the system control is more stable; further, the critical low level 18 is arranged at a range of 5-7 m above the bottom of the treatment cavity of the thickener 12 in the main treatment area 11, and under this level limit condition, the concentration of the discharged slurry is stable and meets the requirements.

[0048] It should be understood that both the delivery pump and the underflow pump 21 at the bottom of the thickener are frequency-controlled to match production needs and reduce energy consumption; the first concentration monitoring unit 3 and the second concentration monitoring unit 20 in the above embodiment can be concentration meters, and the first flow monitoring unit 2 and the second flow monitoring unit 19 can be flow meters.

[0049] In some embodiments, each thickener 12 is also provided with a jet system 16 at its bottom, which is used to input high-speed air to disperse the material at its bottom when discharging the bottom dense layer material, so that the material flow can pass through the discharge end more easily.

[0050] On the other hand, a preferred embodiment of the present invention also provides a mining production system that applies the above-mentioned ultrafine tailings treatment system for tailingsless mines.

[0051] After the processing system of this embodiment is applied to the mining production system, compared with the original system, it can meet the 3-day tailings storage capacity of the beneficiation plant, greatly improve the coordination capability of mining production, and can still smoothly release tailings after 14 days under static storage and full storage conditions. The maintenance cycle can be optimized to more than half a year. The ultrafine tailings processing capacity is increased from 0.7t / m²•h to 1.0t / m²•h, an increase of 43%; the flocculant consumption is reduced from 60g / t to 30g / t, a reduction of 50%; the paste preparation concentration is increased by ≥5% compared with the conventional thickener, and the concentration fluctuation is controlled within ±2%; the power of the conventional deep cone thickener is 45+7.5kw, while the energy consumption of the thickener in this embodiment is 7.5kw, and the energy consumption of two thickeners working at the same time is 15kw, which reduces energy consumption by 71%.

[0052] Example 1

[0053] Taking a phosphate mine in Guizhou as an example, the mine is a tailings-free mine, with all tailings used for underground backfilling. It is equipped with the processing system described in the preferred embodiment above, with a tailings processing capacity of 3000 t / d and 125 t / h. The feed from the beneficiation plant is 200 m³ / h~230 m³ / h, with a concentration of 40%, and a mining scale of 2.5 million t / a. The main processing area has four thickeners, and the conditioning area has one thickener. The backfilling station has two sets of backfill slurry preparation systems, each with a capacity of 120 m³ / h, operating on two shifts / day, with an annual backfilling capacity of 800,000 m³. -20μm tailings account for 60%, belonging to ultra-fine tailings, with a tailings specific gravity of 2.8. All the ultrafine tailings from the plant are pumped to the thickener group. After passing through the pretreatment mechanism, the tailings slurry is distributed to two thickeners or collected by one thickener simultaneously. After thickening, the sludge layer height is detected to be >10m before sand discharge. If the sludge layer height is below 5m and the concentration decreases, sand feeding is stopped. If the underflow concentration of the thickener is too low, the sand can be discharged to another thickener. The original filter press system has been completely eliminated. The tailings processing capacity is 1.1t / ㎡•h. The flocculant dosage is 30g / t. The underflow concentration of the thickener is 65%, with a concentration fluctuation of ±2%. The tailings from the beneficiation plant arrive 4 days after processing, and can be stored for 14 days when the silo is full.

[0054] In the description of the present application, it should be noted that the terms "upper", "lower", "front", "back", etc. indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0055] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0056] The above is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A system for treating ultra-fine tailings in tailings-free mines, characterized in that, include: The thickening unit includes a main processing area (11) and a regulating area (13). The main processing area (11) is equipped with at least two thickeners (12), and the regulating area (13) is equipped with at least one thickener (12). The thickener (12) is used to buffer and concentrate the input tailings. The thickener (12) is a paste storage type thickener without a rake frame. The height-to-diameter ratio of the processing chamber of the thickener (12) is set to 1.8-2.

2. Conveying mechanism (1), used for conveying tailings; The pretreatment unit is connected to the conveying mechanism (1) and each of the thickeners (12) respectively, and is used to distribute the tailings input by the conveying mechanism (1) to each of the thickeners (12); The monitoring and feedback system is set in the thickener unit and the pretreatment unit respectively, and is used to monitor the incoming material concentration, incoming material flow rate, the concentration state of tailings in each thickener (12) and the discharge concentration; The control system is connected to the thickener unit and the pretreatment mechanism respectively. It is used to control the connection status between the pretreatment mechanism and each thickener (12) according to the incoming material concentration and the incoming material flow rate. It is also used to adjust the working status of each thickener (12) according to the tailings concentration and the discharge concentration. The discharge end of each thickener (12) is connected to the stirring system (23) through an output pipe. The monitoring and feedback system includes a second flow monitoring unit (19) and a second concentration monitoring unit (20) respectively installed on each output pipe. The control system includes a reversing mechanism (22) installed on the output pipe in the main processing zone (11). The reversing mechanism (22) is connected to the feed end of the thickener (12) in the regulating zone (13). The control system is used to control the discharge end of the thickener (12) in the main processing zone (11) to connect with the feed end of the thickener (12) in the regulating zone (13) when the sand concentration in each thickener (12) in the main processing zone (11) is lower than a preset value. Each thickener (12) is also equipped with a jet system (16) at the bottom, which is used to input high-speed air to the bottom of the thickener (12) to disperse the material when discharging the bottom dense layer material, so that the material flow can pass through the discharge end more easily.

2. The ultra-fine tailings treatment system for tailings-free mines according to claim 1, characterized in that, The conveying mechanism (1) is connected to the pretreatment mechanism via the conveying pipe (4). The monitoring feedback system includes a first flow monitoring unit (2) and a first concentration monitoring unit (3) disposed on the conveying pipe (4). The pretreatment mechanism includes a distribution box (5) disposed above the thickener unit. The distribution box (5) is connected to the conveying mechanism (1) via the conveying pipe (4). The distribution box (5) is connected to each thickener (12) in the main treatment area (11) via branch pipes (7). The number of branch pipes (7) matches the number of thickeners (12) in the main treatment area (11). Alternatively, the distribution box (5) is connected to each thickener (12) via branch pipes (7). The number of branch pipes (7) matches the number of thickeners (12).

3. The ultra-fine tailings treatment system for tailings-free mines according to claim 1, characterized in that, The thickener (12) in the adjustment zone (13) is equipped with a stepped drainage mechanism (24) to discharge excess water from the clear water layer in the thickener (12) of the adjustment zone (13) when the discharge end of the main processing zone (11) is connected to the adjustment zone (13) and the height position of the clear water layer is matched.

4. The ultra-fine tailings treatment system for tailings-free mines according to claim 1, characterized in that, The ultrafine tailings treatment system also includes a dosing device (26), which is connected to the pretreatment unit via a dosing pipe (6). The dosing device (26) is used to add flocculant to the pretreatment unit via the dosing pipe (6) to premix the flocculant with the incoming material. Alternatively, the dosing device (26) is connected to each of the thickeners (12) via the dosing pipe (6) to add flocculant to the thickeners (12) via the dosing pipe (6) to mix the flocculant with the incoming material. Alternatively, the dosing device (26) is connected to both the pretreatment unit and each of the thickeners (12) via the dosing pipe (6) to add flocculant to both the pretreatment unit and the thickeners (12) via the dosing pipe (6).

5. The ultra-fine tailings treatment system for tailings-free mines according to claim 1, characterized in that, The monitoring and feedback system includes a material level monitoring unit respectively installed in each of the thickeners (12), used to monitor the material level height in the thickener (12), and used to control the material level height of each thickener (12) to be maintained between the critical low material level (18) and the critical high material level (17).

6. The ultra-fine tailings treatment system for tailings-free mines according to claim 5, characterized in that, The material level monitoring unit includes a pressure monitoring unit (14) for monitoring slurry pressure located at the bottom of the thickener (12) and an ultrasonic detection unit (15) for monitoring mud layer height located at the bottom of the thickener (12).

7. The ultrafine tailings treatment system for tailings-free mines according to claim 5, characterized in that, The critical low material level (18) is located within a range of 5m above the bottom of the processing chamber of the thickener (12) in the main processing area (11) to 7m above the bottom of the processing chamber of the thickener (12) in the main processing area (11).

8. A mining production system, characterized in that, The application has the ultrafine tailings treatment system for tailings-free mines as described in any one of claims 1-7.

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