System for recovering valuable minerals from tailing slurry

Abstract

The utility model relates to a system for recovering valuable minerals from tailing slurry, which comprises a hydrocyclone, a cyclone separator, a water pump, a water pump and a water pump, and is characterized in that the hydrocyclone is used for grading the tailing slurry; an inlet of the spiral classifier is communicated with a settled sand outlet of the hydrocyclone; and an inlet of the dehydration unit is communicated with an ore discharge port of the spiral classifier. The system disclosed by the utility model is simple and compact in structure, and can better meet the recycling treatment of valuable minerals in the concentration tailing slurry. The system disclosed by the utility model is particularly suitable for recovering fine bauxite sand in tailing slurry generated in the bauxite ore washing production process, the discharge amount of tailings is reduced, the utilization rate of bauxite resources is improved, the content of Al2O3 in the fine bauxite sand recovered by the system disclosed by the utility model can reach more than 50%, and the production cost is reduced. And the mass ratio of aluminum to silicon can reach more than 5.

Description

Technical Field

[0001] The utility model relates to a system for recovering valuable minerals from tailings slurry, and particularly to a system for recovering fine bauxite from bauxite tailings slurry, belonging to the field of mineral processing equipment. Background Art

[0002] With the development and application of aluminum resources, bauxite resources are becoming increasingly scarce. Most of the main components of bauxite are diaspore. Its beneficiation process usually adopts the method of water washing to separate the ore from clay. The separated bauxite ore enters the alumina production process after being crushed to the qualified size, while the separated slime (i.e., tailings slurry) is concentrated and then sent to the sludge storage tank (tailings pond) for stacking. According to statistics, 1.0 - 2.5 tons of slime are discharged for every 1 ton of alumina produced. However, the slime generated in the conventional beneficiation process still contains a lot of fine-grained bauxite ore sand (0.1 - 1 mm). Directly discharging it into the tailings pond will cause great waste of resources. How to effectively recover the resources in the slime and reduce tailings discharge is a technical problem with great economic value.

[0003] Chinese Patent Application CN115921488A discloses a recovery system for fine bauxite. The recovery system includes a hydrocyclone, a thickening tank, a thickener, a stirring tank, a suspension beneficiation machine, a concentrate tank, a first slurry pump and a second slurry pump; the overflow of the hydrocyclone enters the thickening tank, the underflow of the hydrocyclone is pumped into the thickener by the first slurry pump, the overflow of the thickener enters the thickening tank, the underflow of the thickener is pumped into the stirring tank by the second slurry pump, the slurry in the stirring tank enters the suspension beneficiation machine, the high-silicon tail mud of the suspension beneficiation machine enters the thickening tank, the concentrate slurry of the suspension beneficiation machine enters the concentrate tank, and the concentrate slurry in the concentrate tank is dehydrated to obtain bauxite concentrate. Although this recovery system can recover qualified bauxite concentrate from bauxite tailings slurry, its structure is relatively complex. It is necessary to set a stirring tank on the downstream side of the hydrocyclone to stabilize the concentration of the sand-containing slurry, and then further carry out suspension beneficiation treatment. Obviously, this increases the structural complexity of the recovery system, increases the equipment investment and floor area, and is also not conducive to improving the recovery efficiency. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a system for recovering valuable minerals from tailings slurry with a simpler and more compact structure in view of the deficiencies of the prior art.

[0005] The technical solution adopted by the utility model is as follows:

[0006] A system for recovering valuable minerals from tailings slurry, comprising:

[0007] A hydrocyclone for classifying tailings slurry;

[0008] A spiral classifier, the inlet of which is connected to the sand settling outlet of the hydrocyclone; and

[0009] A dewatering unit, the inlet of which is connected to the ore discharge port of the spiral classifier.

[0010] In this way, after the tailings slurry enters the hydrocyclone and is classified, the sand settling of the hydrocyclone enters the spiral classifier, and the overflow of the hydrocyclone can be discharged out of the system for other treatments such as thickening; the spiral classifier further classifies the sand settling, and after the return sand generated by the spiral classifier enters the dewatering unit for dewatering, concentrate products can be obtained. The overflow of the spiral classifier and the undersize of the dewatering unit can be discharged out of the system for other treatments such as thickening. The concentration of the tailings slurry often fluctuates, making the concentration of the sand settling (i.e., the underflow) generated by the hydrocyclone often unstable. By arranging a spiral classifier on the downstream side of the hydrocyclone, the unstable sand settling transported by the hydrocyclone can be better absorbed and processed, and a better sorting effect can be achieved. Subsequently, through the treatment of the dewatering unit, fine valuable minerals can be obtained, which helps to simplify the equipment structure and improve the treatment efficiency.

[0011] Furthermore, it further includes a sedimentation tank. The sedimentation tank includes a tank body, and the tank body is provided with a feed inlet, an overflow outlet and a sludge discharge port. The height of the position where the overflow outlet is located is higher than the height of the position where the sludge discharge port is located, and the sludge discharge port is connected to the hydrocyclone. Thus, the tailings slurry can be first input into the sedimentation tank. After the tailings slurry is preliminarily settled and separated in the sedimentation tank, the slurry with a higher concentration is input into the hydrocyclone through the sludge discharge port for further treatment, which helps to reduce the treatment amount of the subsequent functional units, improve the treatment efficiency and further reduce the treatment cost; at the same time, it can also play a buffering role and provide a slurry with a more stable concentration for the subsequent functional units.

[0012] Furthermore, a partition wall that divides the tank body into two chambers is provided in the tank body. The overflow outlet and the sludge discharge port are respectively located on one side of the partition wall, and the feed inlet and the sludge discharge port are located on the same side of the partition wall. Thus, the tailings slurry with more solid-phase substances settles on the side where the sludge discharge port is located, and the tailings slurry with fewer solid-phase substances overflows over the partition wall and is further discharged out of the system, which can further improve the sedimentation and separation effect.

[0013] Furthermore, a pump is provided between the sedimentation tank and the hydrocyclone. Thus, the slurry in the sedimentation tank can be conveniently pumped out, and the input rate of the slurry in the hydrocyclone can be controlled.

[0014] Furthermore, the pump is a slurry pump.

[0015] Furthermore, the dewatering unit is a dewatering screen. Thus, through simple screening, the oversize obtained is the valuable mineral; the undersize obtained can be discharged for other treatments.

[0016] Compared with the prior art, the utility model has at least the following beneficial effects:

[0017] (1) The system structure of the utility model is simpler and more compact, and can better meet the recovery and treatment of valuable minerals in the concentrated tailings slurry, which helps to improve the treatment efficiency and reduce the recovery cost.

[0018] (2) The system of the utility model is especially applicable to the recovery of fine bauxite sand in the tailings slurry generated in the bauxite washing production process, reducing the discharge of tailings and improving the utilization rate of bauxite resources. The content of Al2O3 in the fine bauxite sand recovered by the system of the utility model can reach more than 50%, and the mass ratio of aluminum to silicon can reach more than 5. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a flow chart of recovering valuable minerals from the tailings slurry generated by bauxite washing in Embodiment 1 of the utility model.

[0020] Figure 2 is a schematic structural diagram of recovering valuable minerals from the tailings slurry generated by bauxite washing in Embodiment 1 of the utility model.

[0021] In the figure: 1, sedimentation tank; 2, pump; 3, hydrocyclone; 4, spiral classifier; 5, dewatering unit; 6, partition wall; 7, thickener. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The following will refer to the drawings and combine with embodiments to detail the utility model. It should be noted that, without conflict, the embodiments and features in the embodiments of the utility model can be combined with each other. For the convenience of narration, words such as "upper", "lower", "left", and "right" in the following text only indicate the same direction as the upper, lower, left, and right directions of the drawings themselves, and do not limit the structure. Without special instructions, the relevant percentages refer to mass percentages.

[0023] Embodiment 1

[0024] See Figure 2 , a system for recovering valuable minerals from the tailings slurry generated by bauxite washing, comprising:

[0025] Sedimentation tank 1, the sedimentation tank 1 includes a tank body, and the tank body is provided with a feed port, an overflow port and a sludge discharge port, and the height of the position where the overflow port is located is higher than the height of the position where the sludge discharge port is located;

[0026] Hydrocyclone 3, used for classifying the tailings slurry; the sludge discharge port is communicated with the inlet of the hydrocyclone 3;

[0027] Spiral classifier 4, its inlet is communicated with the sand settling outlet of the hydrocyclone 3; and

[0028] The inlet of the dehydration unit 5 is connected to the discharge port of the spiral classifier 4 .

[0029] The tank body is provided with a partition wall 6 which divides the tank body into two chambers. The overflow port and the mud discharge port are respectively located on one side of the partition wall 6. The feed port and the mud discharge port are located on the same side of the partition wall. The overflow port is located lower than the top surface of the partition wall. The feed port is located at a higher height than the mud discharge port. A pump 2 is provided between the sedimentation tank 1 and the hydrocyclone 3. The pump 2 is a slurry pump. The dewatering unit 5 is a dewatering screen.

[0030] It also includes a thickener 7 , and the overflow port of the tank body, the overflow port of the hydrocyclone 3 , the overflow port of the spiral classifier 4 and the drain port of the dehydration unit are all connected to the inlet of the thickener 7 .

[0031] See also Figure 1 The above system is used to recover valuable minerals (bauxite fine sand) from the tailings slurry produced by bauxite washing, including the following steps:

[0032] Step 1: The tailings slurry (ore mud slurry) produced by bauxite washing is input into the sedimentation tank, so that the tailings slurry settles on one side of the sedimentation tank, and the overflow with less sand goes over the baffle and directly enters the thickener;

[0033] Step 2: The coarse sand intercepted by the baffle is transported to the hydrocyclone through the pipeline by the slurry pump, and the overflow of the hydrocyclone flows into the thickener along the pipeline;

[0034] Step 3: The sand from the hydrocyclone flows into the spiral classifier through the pipeline. The return sand generated by the spiral classifier enters the dehydration unit, and the overflow flows into the thickener through the pipeline.

[0035] Step 4: The returned sand is dehydrated by the dehydration unit, and the screen material obtained is the final concentrate product (bauxite fine sand), and the screen material under the dehydration screen flows into the thickener.

[0036] Among them, the particle size of solid particles in the tailings slurry produced by bauxite washing is less than 1mm, the content of Al2O3 in the slurry is 30-40%, and the content of SiO2 is 5-20%.

[0037] The concentration of the slurry pumped into the hydrocyclone after settling in the settling tank is greater than 10%.

[0038] Generally, the Al2O3 content in the bauxite concentrate obtained by the above method is greater than 50%, and the mass ratio of aluminum to silicon is greater than 5.

[0039] Application Example 1

[0040] Taking the tailings slurry produced by washing a bauxite ore as an example, the particle size of the solid particles in the tailings slurry is less than 1 mm, and the contents of the main chemical components Al2O3, SiO2, and Fe2O3 are 37.35%, 15.6%, and 20.23% respectively, and the mass ratio of aluminum to silicon is 2.39.

[0041] The concentrate in the above-mentioned tailings slurry was recovered using the system and method described in Example 1. The on-site industrial production test system was installed on April 20, 2024, completed commissioning on May 1, 2024, and started the test on May 2, 2024. The test lasted until July 2, 2024, for a total of 60 days.

[0042] On May 6, 2024, the concentrations of the tailings slurry, the underflow concentration of the hydrocyclone, and the overflow concentration of the spiral classifier in the test were measured. The measurement results are shown in Table 1.

[0043] Table 1

[0044] Measurement time Tailings pulp concentration (%) Hydrocyclone underflow concentration (%) Spiral classifier overflow concentration (%) 2024.05.06 8.3-10.5 23-33 20-25

[0045] As can be seen from Table 1, the change range of the feed concentration of the tailings slurry entering the system is relatively small, being 8.3 - 10.5%. The underflow concentration of the hydrocyclone is between 23 - 33%, with a relatively large change. This is because both the concentration of the tailings slurry itself and the precipitation effect in the sedimentation tank fluctuate, resulting in corresponding fluctuations in the feed concentration of the hydrocyclone, which has a certain adverse impact on the beneficiation effect. The overflow concentration of the spiral classifier is between 20 - 25%, being relatively stable, and has a good adaptation and buffering effect on the unstable underflow concentration of the hydrocyclone. It can play a relatively good separation role without additionally setting intermediate units such as a mixing tank. The daily production of concentrate in the system is 120 t. According to the system Al2O3 recovery rate = (concentrate output * concentrate Al2O3 content) / (tailings output * original tailings Al2O3 content), the recovery rate was calculated, and the specific details are shown in Table 2.

[0046] Table 2

[0047] Sample number <![CDATA[Al2O3 (%)]]> <![CDATA[SiO2(%)]]> <![CDATA[Fe2O3(%)]]> <![CDATA[TiO2 (%)]]> A / S Recovery rate (%) 20240506-01 51.59 8.13 19.42 3.04 6.35 8.63

[0048] As shown in Table 2, in the concentrate, the content of Al2O3 is 51.59%, the content of SiO2 is 8.13%, the mass ratio of aluminum to silicon is increased from 2.39 to 6.35, the recovery rate is 8.63%, the re-selection effect of the tailings slurry is ideal, and the recovery effect is comparable to that of the prior art CN115921488A. However, the structure of the system adopted in the present utility model is simpler than that of CN115921488A, and there is no need to set a mixing tank on the downstream side of the hydrocyclone.

[0049] In summary, through the system of the present utility model, the recovery and enrichment of Al2O3 from the tailings generated by bauxite ore washing can be realized, and qualified concentrate with an Al2O3 content greater than 50% and a mass ratio of aluminum to silicon greater than 5 can be obtained. At the same time, during the operation of the system of the present utility model, no additional chemicals need to be added, which is green and environmentally friendly; only after precipitation in the sedimentation tank, classification and concentration by the hydrocyclone, scrubbing, classification and dehydration by the spiral classifier and the dewatering screen, concentrate with a mass ratio of aluminum to silicon greater than 5 can be obtained. The system of the present utility model not only has a relatively high concentrate recovery rate, can obtain greater economic benefits, but also can comprehensively utilize tailings resources, effectively reduce the tailings discharge, and can provide effective process technical support and production practice experience for the re-election project of bauxite tailings, producing good ecological and environmental protection benefits, and simplifying the equipment structure, reducing the equipment investment and floor area, which helps to improve the industrial application value.

[0050] The content clarified in the above embodiments should be understood that these embodiments are only used to illustrate the present utility model more clearly, rather than to limit the scope of the present utility model. After reading the present utility model, various equivalent forms of modification of the present utility model by those skilled in the art all fall within the scope defined by the appended claims of this application.

Claims

1. A system for recovering valuable minerals from tailings slurry, characterized in that, Including: A hydrocyclone (3) for classifying tailings slurry; A spiral classifier (4) whose inlet is communicated with the sand settling outlet of the hydrocyclone (3); and A dewatering unit (5) whose inlet is communicated with the discharge port of the spiral classifier (4).

2. The system according to claim 1, wherein It further includes a sedimentation tank (1), the sedimentation tank (1) includes a tank body, the tank body is provided with a feed inlet, an overflow port and a sludge discharge port, the height of the position where the overflow port is located is higher than the height of the position where the sludge discharge port is located, and the sludge discharge port is communicated with the hydrocyclone (3).

3. The system according to claim 2, characterized in that, A partition wall (6) for separating the tank body into two chambers is arranged in the tank body, the overflow port and the sludge discharge port are respectively located on one side of the partition wall (6), and the feed inlet and the sludge discharge port are located on the same side of the partition wall.

4. The system according to claim 2 or 3, wherein A pump (2) is arranged between the sedimentation tank (1) and the hydrocyclone (3).

5. The system according to claim 4, wherein The pump (2) is a slurry pump.

6. The system according to any one of claims 1-3 and 5, characterized in that The dewatering unit (5) is a dewatering screen.

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