A dissolution backset fractionation optimization system

Abstract

The utility model belongs to mineral processing technical field, concretely is a kind of leaching sand return grading optimization system, including sand return pump, cyclone classifier, finished product ore pulp tank, first mill and grading processing unit;The discharge port of leaching desiliconization groove is connected with the sand return pump, the discharge port of sand return pump is connected with the feed inlet of cyclone classifier, the overflow port of cyclone classifier is connected with the finished product ore pulp tank, the underflow port of cyclone classifier is connected with the feed inlet of first mill, the discharge port of first mill is connected with the grading processing unit, and the overflow port of grading processing unit is connected with the finished product ore pulp tank.The utility model is synergic design by multistage classification and grinding, improves sand return grading efficiency and finished product ore pulp quality, reduces equipment load, realizes system stable and efficient operation.

Description

Technical Field

[0001] This utility model relates to the field of mineral processing technology, specifically to a leaching return sand grading and optimization system. Background Technology

[0002] In the Bayer process for alumina production, leaching and return sand is an essential step. Currently, two common methods of return sand are used both domestically and internationally: one is direct return to the mill head, and the other is pumping it to a hydrocyclone for classification before it enters the mill. In the mineral leaching process, the leached slurry contains slurry components of the appropriate particle size and coarse return sand. Classification is necessary to separate the qualified slurry from the return sand to ensure the efficient operation of subsequent processes. In existing technologies, return sand classification systems typically use a single classifier, which suffers from low classification efficiency and incomplete return sand treatment: some coarse return sand enters the finished slurry without sufficient grinding, leading to a decline in the quality of the finished slurry; simultaneously, a single classification process easily causes uneven equipment load, affecting the overall operational stability of the system and increasing energy consumption and maintenance costs. Utility Model Content

[0003] To address the shortcomings of existing technologies, this utility model provides an optimized leaching return sand classification system. Through multi-stage classification and grinding synergistic design, it improves the efficiency of return sand classification and the quality of finished slurry, reduces equipment load, and achieves stable and efficient system operation.

[0004] To achieve the above objectives, this utility model provides the following technical solution: A leaching return sand classification and optimization system includes: a return sand pump, a hydrocyclone classifier, a finished slurry tank, a first mill, and a classification and processing unit; The outlet of the leaching and desilication tank is connected to the return sand pump, the outlet of the return sand pump is connected to the inlet of the cyclone classifier, the overflow outlet of the cyclone classifier is connected to the finished product slurry tank, the underflow outlet of the cyclone classifier is connected to the inlet of the first mill, the outlet of the first mill is connected to the classification processing unit, and the overflow outlet of the classification processing unit is connected to the finished product slurry tank.

[0005] Preferably, the grading unit includes an intermediate tank, an intermediate pump, and a hydrocyclone. The intermediate tank is connected to the mill, the intermediate tank is connected to the intermediate pump, the intermediate pump is connected to the hydrocyclone, and the overflow port of the hydrocyclone is connected to the finished product slurry tank.

[0006] Preferably, the intermediate trough includes a first intermediate trough, a second intermediate trough, and a third intermediate trough, which are connected in parallel with the first mill.

[0007] Preferably, the intermediate pump includes a first intermediate pump, a second intermediate pump, and a third intermediate pump, wherein the first intermediate pump is connected to the first intermediate tank, the second intermediate pump is connected to the second intermediate tank, and the third intermediate pump is connected to the third intermediate tank.

[0008] Preferably, the hydrocyclone includes a first hydrocyclone, a second hydrocyclone, and a third hydrocyclone, wherein the first hydrocyclone is connected to the first intermediate pump, the second hydrocyclone is connected to the second intermediate pump, and the third hydrocyclone is connected to the third intermediate pump.

[0009] Preferably, the underflow ports of the first hydrocyclone, the second hydrocyclone, and the third hydrocyclone are all connected to a second mill.

[0010] Preferably, the bottom outlet of the finished slurry tank is connected to the return sand pump.

[0011] Preferably, the outlet of the finished slurry tank is connected to a finished slurry pump, and the finished slurry pump is connected to a desiliconization heat exchange sleeve.

[0012] This invention provides a leaching and return sand classification and optimization system. Compared with the prior art, it has the following advantages: 1. By combining preliminary classification with a hydrocyclone classifier with secondary classification using multiple hydrocyclones, the classification accuracy is improved, ensuring uniform particle size of the finished slurry and significantly enhancing its quality.

[0013] 2. The coarse-particle return sand is ground multiple times in the first and second mills, and combined with reflux circulation to avoid resource waste and improve the utilization rate of slurry.

[0014] 3. Extend the cycle of agitators and cleaning in the finished product tank and pre-desilicon tank to reduce unplanned downtime accidents. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the connection structure of this utility model.

[0016] In the diagram: 1. Leaching and desilication tank; 2. Return sand pump; 3. Hydrocyclone classifier; 4. Finished product slurry tank; 5. First mill; 6. Classification unit; 7. First intermediate tank; 8. Second intermediate tank; 9. Third intermediate tank; 10. First intermediate pump; 11. Second intermediate pump; 12. Third intermediate pump; 13. First hydrocyclone; 14. Second hydrocyclone; 15. Third hydrocyclone; 16. Second mill; 17. Finished product slurry pump; 18. Desilication heat exchanger jacket. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Please see Figure 1 This utility model provides a technical solution: a leaching and return sand grading optimization system.

[0019] In one embodiment of this utility model, the leaching return sand classification and optimization system includes a return sand pump 2, a cyclone classifier 3, a finished slurry tank 4, a first mill 5, and a classification processing unit 6; The outlet of the leaching and desilication tank 1 is connected to the return sand pump 2, the outlet of the return sand pump 2 is connected to the inlet of the cyclone classifier 3, the overflow outlet of the cyclone classifier 3 is connected to the finished product slurry tank 4, the underflow outlet of the cyclone classifier 3 is connected to the inlet of the first mill 5, the outlet of the first mill 5 is connected to the classification processing unit 6, and the overflow outlet of the classification processing unit 6 is connected to the finished product slurry tank 4.

[0020] In this embodiment, the bottom outlet of the finished slurry tank 4 is connected to the return sand pump 2, the outlet of the finished slurry tank 4 is connected to the finished slurry pump 17, and the finished slurry pump 17 is connected to the desiliconization heat exchange sleeve 18.

[0021] The return sand pump 2, as the power core of the system, is a wear-resistant centrifugal pump adapted to the characteristics of high solid content and high abrasiveness of the leaching slurry. Its function is to transport the slurry in the leaching desilication tank 1 to the cyclone classifier 3 at a stable pressure, so as to avoid the slurry from depositing and clogging in the pipeline.

[0022] The hydrocyclone classifier 3, as the core of the primary classification, adopts a hydrocyclone and utilizes the combined effect of centrifugal force and gravity to achieve slurry classification. Its working principle is as follows: the slurry enters the hydrocyclone tangentially from the feed inlet, forming a high-speed rotating flow field inside the cylinder. Fine particles of qualified particle size are discharged from the overflow outlet with the upward flow, while coarse particles are discharged from the underflow outlet with the downward flow.

[0023] The finished slurry tank 4 is a cylindrical tank with an internal stirring device (such as a paddle mixer) to prevent slurry settling. Its main functions include: receiving qualified overflow slurry from the cyclone classifier 3 and the classification processing unit 6; buffering the slurry to stabilize the subsequent discharge pressure; separating coarse particles from the bottom of the tank and returning them to the return sand pump 2.

[0024] The first mill 5, serving as the primary grinding core, is typically a grid-type ball mill, suitable for grinding coarse particles returning to the sand. Its grinding media are steel balls, which, through the impact and grinding action of the steel balls, grind the coarse particles in the underflow of the cyclone classifier to 0.05-0.1mm, providing a qualified particle size basis for subsequent secondary classification.

[0025] The grading unit 6, as the core of the secondary grading, is a deep grading device for the slurry after grinding by the first mill 5, making up for the deficiencies of the primary grading and ensuring that the particle size of the slurry that finally enters the finished slurry tank 4 fully meets the requirements.

[0026] Understandably, the overall process is as follows: First, the hydrocyclone classifier 3 quickly separates most of the qualified slurry, reducing the processing capacity of subsequent grinding equipment and lowering energy consumption; only the coarse particles are ground to avoid over-grinding, i.e., the qualified fine particles become too fine due to repeated grinding, affecting the subsequent settling efficiency; the ground slurry is then classified a second time by the classification unit 6 to ensure that no coarse particles are missed, significantly improving the quality of the finished slurry.

[0027] In one embodiment of this utility model, the grading processing unit 6 includes an intermediate tank, an intermediate pump, and a hydrocyclone. The intermediate tank is connected to the mill, the intermediate tank is connected to the intermediate pump, the intermediate pump is connected to the hydrocyclone, and the overflow port of the hydrocyclone is connected to the finished product slurry tank.

[0028] In this embodiment, the intermediate tank is a rectangular or cylindrical tank, located between the first mill 5 and the intermediate pump. Its main functions include: receiving the grinding slurry discharged from the first mill 5 to avoid flow fluctuations caused by the slurry directly entering the pump body; adjusting the slurry concentration, which can be controlled at 20%-25% by adding dilution water to meet the grading requirements of the hydrocyclone; and settling some large particle impurities to protect the subsequent pump body and hydrocyclone.

[0029] The intermediate pump is a wear-resistant slurry pump, whose function is to deliver the slurry in the intermediate tank to the hydrocyclone at a stable flow rate and pressure, ensuring a stable rotating flow field within the hydrocyclone and improving classification accuracy. Compared to the return sand pump, the intermediate pump has a lower delivery pressure but requires higher flow stability.

[0030] The hydrocyclone is a small, high-efficiency hydrocyclone, and its classification principle is the same as that of a hydrocyclone classifier, but with higher classification accuracy. Through two-stage classification, the small amount of coarse particles (particle size > 0.1 mm) that remain after the first mill grinding can be separated, ensuring that the overflow slurry fully meets the requirements of the finished product.

[0031] Understandably, the intermediate trough solves the problem of fluctuating discharge flow from the first mill, provides stable feeding conditions for the intermediate pump, and the independent intermediate pump ensures that the hydrocyclone obtains stable working pressure, avoiding the impact of pressure fluctuations in the return sand pump on the secondary classification effect. The high-precision classification of the secondary hydrocyclone further improves the quality of the finished slurry.

[0032] In one embodiment of the present invention, the intermediate groove includes a first intermediate groove 7, a second intermediate groove 8 and a third intermediate groove 9, and the first intermediate groove 7, the second intermediate groove 8 and the third intermediate groove 9 are connected in parallel with the first mill 5.

[0033] In this embodiment, the discharge port of the first mill 5 is first connected to the main distribution pipe. The main distribution pipe is equipped with three branch pipes, which are respectively connected to the feed ports of the first intermediate tank 7, the second intermediate tank 8, and the third intermediate tank 9. Each branch pipe is equipped with an electric regulating valve and a flow sensor. The slurry flow rate of each branch pipe is monitored and adjusted in real time by the central control system to ensure that the feed amount of the three intermediate tanks is evenly distributed. The three intermediate tanks have the same volume and are equipped with a liquid level sensor and a stirring device. The liquid level sensor is linked with the electric regulating valve of the corresponding branch pipe. When the liquid level of an intermediate tank exceeds 2 / 3, the flow rate of that branch pipe is automatically reduced. When the liquid level is below 1 / 3, the flow rate is automatically increased to avoid overflow or empty tanks. The stirring device speed is controlled at 60-80 r / min to prevent the slurry from settling and stratifying in the tank.

[0034] The three intermediate tanks operate independently and are not dependent on each other. If the first intermediate tank 7 needs to be shut down for maintenance due to a malfunction of the mixing device, only the valves of the corresponding branch pipes need to be closed. The second intermediate tank 8 and the third intermediate tank 9 can continue to receive slurry and supply material normally. The total system throughput will only decrease by 1 / 3, and there is no need to shut down the entire system.

[0035] In one embodiment of the present invention, the intermediate pump includes a first intermediate pump 10, a second intermediate pump 11 and a third intermediate pump 12. The first intermediate pump 10 is connected to the first intermediate tank 7, the second intermediate pump 11 is connected to the second intermediate tank 8, and the third intermediate pump 12 is connected to the third intermediate tank 9.

[0036] In this embodiment, the inlet of the first intermediate pump 10 is connected to the outlet of the first intermediate tank 7 via a flange. The connection method of the second intermediate pump 11 and the third intermediate pump 12 is the same as that of the first intermediate pump 10, corresponding to the second intermediate tank 8 and the third intermediate tank 9 respectively. The three sets of intermediate pumps work in parallel, and each pump only needs to process the slurry of the corresponding intermediate tank, avoiding long-term high-load operation of a single pump and reducing the number of maintenance times.

[0037] In one embodiment of this utility model, the hydrocyclone includes a first hydrocyclone 13, a second hydrocyclone 14, and a third hydrocyclone 15. The first hydrocyclone 13 is connected to the first intermediate pump 10, the second hydrocyclone 14 is connected to the second intermediate pump 11, and the third hydrocyclone 15 is connected to the third intermediate pump 12. The underflow outlets of the first hydrocyclone 13, the second hydrocyclone 14, and the third hydrocyclone 15 are all connected to a second mill 16.

[0038] In this embodiment, the first hydrocyclone 13, the second hydrocyclone 14, and the third hydrocyclone 15 are of the same model and specifications, all made of wear-resistant polyurethane. The inlet of each hydrocyclone is connected to the outlet of the corresponding intermediate pump via a high-pressure hose to prevent pump vibration from being transmitted to the hydrocyclone and affecting the classification stability. The overflow port is connected to the finished slurry tank 4 via a collection pipe, and the underflow port is connected to the second mill 16 via a pipe. The three hydrocyclones are installed at the same height and are all equipped with pressure sensors and flow regulating valves.

[0039] Among them, the second mill 16 adopts an overflow ball mill, which has higher grinding precision than the first mill (grid type) and is suitable for the fine grinding requirements of coarse particles in the underflow of the secondary hydrocyclone. The discharge port of the second mill 16 is connected to the feed port of the corresponding intermediate tank through a pipe, forming a closed loop process of "underflow of the secondary hydrocyclone → grinding in the second mill → return to the intermediate tank".

[0040] Working principle: The slurry after leaching and desilication is transported to the hydrocyclone classifier 3 by the return sand pump 2 for preliminary classification: the overflow slurry of qualified particle size directly enters the finished product slurry tank 4, and the coarse particles flow into the first mill 5 for grinding; the slurry after grinding in the first mill 5 enters the first intermediate tank 7, the second intermediate tank 8, and the third intermediate tank 9 in parallel for buffering, and then is transported to the first hydrocyclone 13, the second hydrocyclone 14, and the third hydrocyclone 15 by the corresponding first intermediate pump 10, the second intermediate pump 11, and the third intermediate pump 12 for secondary classification. The overflow slurry after secondary classification flows into the finished product slurry tank 4, and the coarse particles flow into the second mill 16 for further grinding. After grinding, the slurry flows back to the classification system for closed-loop processing. The qualified slurry in the finished product slurry tank 4 is transported to the desilication heat exchange tube sleeve 18 by the finished product slurry pump 17, and the coarse particles flow back to the return sand pump 2 for reclassification, thus achieving full-process optimization.

[0041] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the present invention to the precise forms disclosed, and it is obvious that many changes and variations can be made based on the above teachings. Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the present invention and are not intended to limit the invention. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. The purpose of selecting and describing exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art, after reading this specification, can make modifications, substitutions, variations, and various choices and changes to the embodiments as needed without departing from the principles and spirit of the present invention, provided that such modifications, substitutions, variations, and choices and changes are within the scope of the claims of the present invention and are protected by patent law.

Claims

1. A leaching and return sand classification and optimization system, characterized in that, Includes a return sand pump, a hydrocyclone classifier, a finished slurry tank, a first mill, and a classification processing unit; The outlet of the leaching and desilication tank is connected to the return sand pump, the outlet of the return sand pump is connected to the inlet of the cyclone classifier, the overflow outlet of the cyclone classifier is connected to the finished product slurry tank, the underflow outlet of the cyclone classifier is connected to the inlet of the first mill, the outlet of the first mill is connected to the classification processing unit, and the overflow outlet of the classification processing unit is connected to the finished product slurry tank.

2. The leaching and return sand classification and optimization system according to claim 1, characterized in that: The grading unit includes an intermediate tank, an intermediate pump, and a hydrocyclone. The intermediate tank is connected to the mill, the intermediate tank is connected to the intermediate pump, the intermediate pump is connected to the hydrocyclone, and the overflow port of the hydrocyclone is connected to the finished product slurry tank.

3. The leaching and return sand classification and optimization system according to claim 2, characterized in that: The intermediate trough includes a first intermediate trough, a second intermediate trough, and a third intermediate trough, which are connected in parallel with the first mill.

4. The leaching and return sand classification and optimization system according to claim 3, characterized in that: The intermediate pump includes a first intermediate pump, a second intermediate pump, and a third intermediate pump. The first intermediate pump is connected to the first intermediate tank, the second intermediate pump is connected to the second intermediate tank, and the third intermediate pump is connected to the third intermediate tank.

5. The leaching and return sand classification and optimization system according to claim 4, characterized in that: The hydrocyclone includes a first hydrocyclone, a second hydrocyclone, and a third hydrocyclone. The first hydrocyclone is connected to the first intermediate pump, the second hydrocyclone is connected to the second intermediate pump, and the third hydrocyclone is connected to the third intermediate pump.

6. The leaching and return sand classification and optimization system according to claim 5, characterized in that: The underflow ports of the first, second, and third hydrocyclones are all connected to the second mill.

7. The leaching and return sand classification and optimization system according to claim 1, characterized in that: The bottom outlet of the finished slurry tank is connected to the return sand pump.

8. The leaching and return sand classification and optimization system according to claim 1, characterized in that: The outlet of the finished slurry tank is connected to the finished slurry pump, and the finished slurry pump is connected to the desiliconization heat exchange sleeve.

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