A continuous production system for qualified electrolytic manganese dioxide solution

Abstract

This utility model belongs to the technical field of hydrometallurgical production line systems, specifically disclosing a continuous production system for qualified electrolytic manganese dioxide solution. It includes, from front to back, a first leaching tank, a second leaching tank, a third leaching tank, a fourth leaching tank, a first neutralization tank, a second neutralization tank, a thickener, a first purification tank, a second purification tank, a third purification tank, a fourth purification tank, and a fifth purification tank. Except for the fifth purification tank, the upper end of the side wall of the tank closest to the next tank in each of the other tanks is provided with an overflow outlet. Except for the first leaching tank and the first purification tank, the upper end of the side wall of the tank closest to the previous tank in each of the other tanks is provided with an overflow inlet. The overflow outlet of the previous tank is connected to the overflow inlet of the next tank via a pipe. The overflow outlet of the second neutralization tank is connected to the upper side wall of the thickener via a pipe. This utility model's system has advantages such as high equipment utilization, high solid-liquid separation efficiency, low control difficulty, low investment, and good economic benefits.

Description

Technical Field

[0001] This utility model relates to the technical field of hydrometallurgical production line systems, and in particular to a continuous production system for qualified electrolytic manganese dioxide solution. Background Technology

[0002] In the early days of the battery industry, primary batteries were made using natural manganese dioxide ore. In 1918, Van Arsdale in the United States successfully produced electrolytic manganese dioxide (EMD) and discovered that using EMD instead of natural manganese dioxide in primary batteries significantly improved the battery's discharge performance. With advancements in science and technology and economic development, the use of various electrical appliances has become increasingly widespread, placing ever-higher demands on the performance of primary batteries, thus promoting the development of the primary battery industry and the upgrading of products.

[0003] Currently, similar enterprises both domestically and internationally all employ intermittent leaching processes, with largely the same process principles and flow, including: leaching → iron removal → heavy metal removal → electrolysis → washing → grinding → mixing. One-step leaching is used with manganese oxide ore (MnO2) and pyrite (FeS2) in combination with sulfuric acid; or leaching is performed with manganese monoxide (MnO) in combination with sulfuric acid, and the addition of manganese dioxide powder and ferrous oxide (Fe2O3). 2+ →Fe 3+ The process involves using limestone to adjust the pH value for iron removal and barium sulfide as the heavy metal removal reagent to prepare a qualified manganese sulfate solution. The process flow diagram is shown below. Figure 1 As shown.

[0004] The following main reactions are involved in the basic steps of leaching, iron removal, weight removal, electrolysis, washing, grinding, and mixing:

[0005] (1) Leaching, main reaction equation for removing potassium, sodium, and iron:

[0006] ;

[0007] ;

[0008] ;

[0009] ;

[0010] ;

[0011] ;

[0012] ;

[0013] ;

[0014] ;

[0015] ;

[0016] ;

[0017] ;

[0018] ;

[0019] (2) Main reaction equation for the removal of heavy matter:

[0020] ;

[0021] ;

[0022] ;

[0023] (3) The main reaction equation for electrolysis:

[0024] .

[0025] In engineering practice, the time required for the batch reaction to complete all liquid preparation processes is 22 hours, of which the effective chemical reaction time is 8 hours and the non-essential time is 14 hours, including 6 hours for feeding and transfer, and 8 hours for filtration. During the non-essential time, the solution temperature drops from 95℃ to 75℃. The operation time and temperature changes of the batch operation are shown in Table 1 below:

[0026] Table 1. Changes in time and temperature during intermittent leaching, degravimetric analysis, and electrolysis.

[0027]

[0028] Based on the formula Q=ρ·V·c·ΔT, a 20,000-ton / year electrolytic manganese dioxide plant requires approximately 2400 m³ of liquid solution per day. 3 The heat lost by this portion of the solution due to non-effective time processes such as filtration and transfer is 200.64 × 10⁻⁶. 6 kJ. This portion of the qualified manganese sulfate solution at low temperature needs to be reheated to 95℃ before entering electrolysis, requiring >98.84 tons of steam at 175℃. Therefore, the intermittent leaching electrolysis manganese dioxide production process has disadvantages such as low efficiency, high unit energy consumption, inability to maintain optimal reaction conditions, low solid-liquid separation efficiency, and large fixed asset investment. Specifically:

[0029] (1) Low efficiency and high energy consumption per unit

[0030] Intermittent reaction vessel (assuming 200m) 3The leaching tank agitator (with a power output of 75 kW) requires 6 hours to complete the chemical reaction, and 22 hours to complete all operations in a single tank. The tank utilization rate = chemical reaction time / time required for a single tank to complete all operations = 6 / 22 = 27.27%, which is equivalent to an effective operating efficiency of 27.27%. The agitator motor cannot be stopped before completing the four processes of feeding, reaction, discharge, and filtration; therefore, the wasted electricity is 75 × (22 - 6) = 1200 kW·h. -1 The heat lost due to non-effective time processes such as filtration and transfer is 200.64 × 10⁶ kJ / d, which is equivalent to 98.84 t / d of saturated steam at 175℃.

[0031] (2) Unable to maintain optimal reaction conditions

[0032] The conditions for batch leaching (temperature, concentration, pH, etc.) change dynamically throughout the batch process. Initially, the reactant concentration is highest, and the reaction rate is fastest; as the reaction proceeds, the concentration of effective minerals decreases, the concentration of manganese ions in the solution increases, and the reaction rate gradually slows down. To ensure the reaction is completed, a longer reaction time is often required, resulting in the equipment operating at low efficiency for some periods.

[0033] (3) Low solid-liquid separation efficiency

[0034] Fe in manganese sulfate solution 3+ Al 3+ Impurity ions are neutralized with calcium carbonate or manganese monoxide respectively to form Fe(OH)3 and Al(OH)3 solids, which are then separated into solid and liquid components. Ni 2+ Cu 2+ Heavy metal impurities are treated by reacting barium sulfide and manganese sulfide to form heavy metal precipitates such as NiS and CuS, followed by solid-liquid separation. Because these are newly produced substances through chemical reactions, the impurity particles are very fine (0.1~6μm), preventing crystal growth. This results in low separation efficiency and impurity back-dissolution during solid-liquid separation, leading to large fluctuations in impurity content in each batch of manganese sulfate solution. Furthermore, direct pressure filtration of the solution results in high impurity content per 100m³ of filtration. 3 Only a solution can effectively separate 3-5% of solid impurities, resulting in low solid-liquid separation efficiency.

[0035] (4) Large investment and low equipment utilization rate

[0036] Taking a 20,000-ton electrolytic manganese dioxide production project as an example: using traditional intermittent leaching and intermittent impurity removal, 45-50 kg / m³ of manganese dioxide needs to be produced daily. 3 Qualified manganese sulfate solution 2400m 3 12 200m units are needed. 3 12 mixing tanks, 250m³ each 2 Filter press, 6 x 200m 36 250m³ purification tanks 2 The filter press has 18 pumps of various types, with an installed power of 2460kW. The actual operating power is 729.2kW, resulting in an equipment utilization rate of 29.6%. The power consumption per cubic meter of qualified manganese sulfate solution is 9.11 kWh. -1 / m 3 .

[0037] Therefore, improving equipment utilization, enhancing solid-liquid separation and filtration, and ensuring solution purity are essential in electrolytic manganese dioxide systems. Utility Model Content

[0038] In view of the above-mentioned problems, this utility model provides a continuous production system for qualified electrolytic manganese dioxide solution. The system of this utility model has advantages such as high equipment utilization, high solid-liquid separation efficiency, low control difficulty, low investment, and good economic benefits.

[0039] To address the aforementioned problems, this utility model provides a continuous production system for qualified electrolytic manganese dioxide solution. The system includes, from front to back, a first leaching tank, a second leaching tank, a third leaching tank, a fourth leaching tank, a first neutralization tank, a second neutralization tank, a concentrator, a first purification tank, a second purification tank, a third purification tank, a fourth purification tank, and a fifth purification tank. Except for the fifth purification tank, the upper end of the side wall of the tank closest to the next tank in each of the other tanks is provided with an overflow outlet. Except for the first leaching tank and the first purification tank, the upper end of the side wall of the tank closest to the previous tank in each of the other tanks is provided with an overflow inlet. The overflow outlet of the previous tank... The overflow inlet of the first tank is connected to the overflow outlet of the second neutralization tank via a pipe; the overflow outlet of the second neutralization tank is connected to the upper side wall of the concentrator via a pipe; the bottom of the fourth leaching tank is sequentially connected to a first pump and a horizontal screw centrifuge, the bottom of the concentrator is connected to a second pump, and the horizontal screw centrifuge and the second pump are respectively connected to the third leaching tank; the bottom of the side wall of the fifth purification tank is provided with a first discharge port, and the lower side wall of the fifth purification tank is provided with a second discharge port; the first discharge port is connected to the second purification tank via a third pump, and the second discharge port is connected to the second filter press via a pipe.

[0040] Preferably, each trough has a turbulence column on its inner wall.

[0041] Preferably, an overflow pipe is provided at the overflow outlet in the tank. It should be noted that the reacted solution in the tank enters from below the overflow pipe and exits from above the overflow outlet and / or the overflow pipe.

[0042] Preferably, a feeding port is provided above the third leaching tank, and the horizontal screw centrifuge and the second pump are respectively connected to the feeding port of the third leaching tank through pipelines.

[0043] Preferably, a feeding port is provided above the first purification tank, and the feeding port of the first purification tank is connected to the top of the concentrator through a first filter press.

[0044] Preferably, the height difference between the first discharge port and the second discharge port is 3.0m.

[0045] Preferably, a feeding port is provided above the first leaching tank / first neutralization tank.

[0046] Preferably, a feeding port is provided above the second purification tank, and the first discharge port is connected to the feeding port of the second purification tank.

[0047] Preferably, the pipe connecting the bottom of the fourth leaching tank to the first pump is a filter residue pipe.

[0048] Preferably, the first leaching tank, the second leaching tank, the third leaching tank, the fourth leaching tank, the first neutralization tank, the second neutralization tank, the first purification tank, the second purification tank, the third purification tank, the fourth purification tank, and the fifth purification tank are all equipped with stirring paddles, which are connected to a stirring pump at the top of the tank.

[0049] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0050] (1) The system of this utility model uses the second pump at the bottom of the concentrator to return the rich Fe(OH)3 particles and Al(OH)3 particles at the bottom of the concentrator to the third leaching tank (neutralization reaction stage), which promotes the growth of Fe(OH)3 and Al(OH)3 crystal particles, and transforms Fe(OH)3 and Al(OH)3 from a highly scale-inhibiting colloidal state into easily filterable crystalline particles (10-100μm), increasing the unit filtration rate of the same equipment by more than 3 times.

[0051] (2) Compared with traditional filter presses (including feeding, filtration and slag discharge, the equipment operation rate is relatively low), the system of this utility model uses a horizontal screw centrifuge as the filtration equipment (10-750μm), which can meet the requirements of the seed crystal circulation process of this system.

[0052] (3) The bottom of the fifth purification tank of the present invention is provided with a first discharge port to transport the mature NiS, CuS and ZnS seed particles at the bottom of the fifth purification tank to the second purification tank as seed particles for the purification and heavy metal removal process, which promotes the growth of heavy metal precipitation crystal particles, reduces the consumption of heavy metal removal reagent by more than 50%, and increases the unit filtration rate of the same equipment by 3 to 5 times.

[0053] (4) The system of this utility model uses a horizontal screw centrifuge to separate the leaching residue. The iron content in the solution is controlled to below 0.2ppm through seed crystal circulation and other means. Solid-liquid separation is carried out separately through the two discharge ports (first discharge port and second discharge port) of the fifth purification tank, so as to achieve efficient separation of heavy metals and lay the foundation for comprehensive utilization of resources. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of the continuous production system for qualified electrolytic manganese dioxide solution according to this utility model;

[0055] Figure 2 This is a schematic diagram of the structure inside any tank in the novel continuous production system for qualified electrolytic manganese dioxide solution in this experiment.

[0056] Explanation of reference numerals in the attached figures:

[0057] 1. First leaching tank; 2. Second leaching tank; 3. Third leaching tank; 4. Fourth leaching tank; 5. First neutralization tank; 6. Second neutralization tank; 7. Concentrator; 8. First purification tank; 9. Second purification tank; 10. Third purification tank; 11. Fourth purification tank; 12. Fifth purification tank; 13. Overflow outlet; 14. Overflow inlet; 15. First pump; 16. Horizontal screw centrifuge; 17. Second pump; 18. First discharge port; 19. Second discharge port; 20. Third pump; 21. Second filter press; 22. Turbulence column; 23. Overflow pipe; 24. First filter press; 25. Agitator; 26. Agitator pump. Detailed Implementation

[0058] To make the present invention easier to understand, specific embodiments are described below to further illustrate the invention. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical terms used below have the same meaning as understood by those skilled in the art; unless otherwise specified, the raw materials and reagents involved herein can be purchased commercially or obtained by known methods.

[0059] It should be noted that this system includes a first leaching tank and a second leaching tank for the leaching process, a third leaching tank and a fourth leaching tank for the oxidation process, and a first neutralization tank and a second neutralization tank for the neutralization process.

[0060] It should be noted that the thickener, horizontal screw centrifuge, turbulence column, overflow pipe, filter press, stirring pump, and stirring paddle in this system are all common equipment that can be purchased from the market.

[0061] To address the problems mentioned in the background section, this invention provides a continuous production system for qualified electrolytic manganese dioxide solution. The system of this invention has advantages such as high equipment utilization, high solid-liquid separation efficiency, low control difficulty, low investment, and good economic benefits.

[0062] The following detailed explanation is further illustrated with specific examples.

[0063] A continuous production system for qualified electrolytic manganese dioxide solution, such as Figure 1-2As shown, this utility model provides a continuous production system for qualified electrolytic manganese dioxide solution. The system includes, from front to back, a first leaching tank 1, a second leaching tank 2, a third leaching tank 3, a fourth leaching tank 4, a first neutralization tank 5, a second neutralization tank 6, a concentrator 7, a first purification tank 8, a second purification tank 9, a third purification tank 10, a fourth purification tank 11, and a fifth purification tank 12. Except for the fifth purification tank 12, the upper end of the side wall of the tank closest to the next tank in each of the other tanks is provided with an overflow outlet 13. Except for the first leaching tank 1 and the first purification tank 8, the upper end of the side wall of the tank closest to the previous tank in each of the other tanks is provided with an overflow inlet 14. The overflow outlet 13 of the previous tank and the overflow inlet 14 of the next tank are connected. The liquid outlet 14 is connected via a pipe; the overflow outlet 13 of the second neutralization tank 6 is connected to the upper side wall of the concentrator 7 via a pipe; the bottom of the fourth leaching tank 4 is sequentially connected to the first pump 15 and the horizontal screw centrifuge 16, the bottom of the concentrator 7 is connected to the second pump 17, and the horizontal screw centrifuge 16 and the second pump 17 are respectively connected to the third leaching tank 3; the bottom of the fifth purification tank 12 has a first discharge port 18 at the bottom of its side wall, and a second discharge port 19 is located below the side wall of the fifth purification tank; the first discharge port 18 is connected to the second purification tank 9 via the third pump 20, and the second discharge port 19 is connected to the second filter press 21 via a pipe. Each tank's inner wall is equipped with a turbulence column 22. The edge of the overflow outlet 13 in the tank is equipped with an overflow pipe 23. The upper part of the third leaching tank 3 has a feeding port, and the horizontal screw centrifuge 16 and the second pump 17 are respectively connected to the feeding port of the third leaching tank 3 via pipes. A feeding port is provided above the first purification tank 1, and the feed port of the first purification tank 8 is connected to the first filter press 24 above the thickener 7. The height difference between the first discharge port 18 and the second discharge port 19 is 3.0m. A feeding port is provided above the first leaching tank 1 / first neutralization tank 5. A feeding port is provided above the second purification tank 9, and the first discharge port 18 is connected to the feeding port of the second purification tank 9. The first leaching tank 1, second leaching tank 2, third leaching tank 3, fourth leaching tank 4, first neutralization tank 5, second neutralization tank 6, first purification tank 8, second purification tank 9, third purification tank 10, fourth purification tank 11 and fifth purification tank 12 are all equipped with stirring paddles 25, which are connected to stirring pumps 26 at the top of the tank. Each tank has a turbulence column 22 on its inner wall. An overflow pipe 23 is provided at the edge of the overflow outlet 13 in the tank.

[0064] Example 2

[0065] In the process of preparing qualified electrolytic manganese dioxide solution (manganese sulfate solution) using the continuous production system for qualified electrolytic manganese dioxide solution of Example 1,

[0066] like Figure 1As shown, in the above process, manganese monoxide (with a particle size of -150um accounting for more than 90%), concentrated sulfuric acid, and electrolytic solution are added to the feed port of the first leaching tank; wherein, the amount of manganese monoxide used is 2.6-10.5t, and the manganese content in the manganese monoxide accounts for 12-50% of the total manganese mass in the manganese monoxide and electrolytic solution; the reaction temperature in the first leaching tank is 80-100℃, the reaction time is 0.5-3.4h, the solid content of the reaction system solution in the tank is 2.6%~10.5%, and the stirring intensity is 15-75r / min.

[0067] In the above process, pyrolusite powder is added to the third leaching tank as an oxidant to react with Fe. 2+ All were oxidized to Fe 3 + The dosage is 5-30 wt% of manganese dioxide, the manganese content is 18-40 wt%, the reaction time is 0.5-3.4 h (the specific parameters vary depending on the manganese content in the raw materials), and the reaction temperature and stirring intensity are the same as above.

[0068] In the above process, manganese monoxide (the same as the raw material) or limestone is added to the first neutralization tank to adjust the pH value (adjusted within the range of 3.1-5.5) to accelerate the precipitation of Fe(OH)3 and Al(OH)3. The seed crystal circulation volume at the bottom of the concentrator is 5-75 wt% of the amount of electrolytic manganese dioxide solution (manganese sulfate solution), and the solid content at the bottom of the concentrator is 5-30 wt%.

[0069] In the above process, the overflow solids content at the overflow port of the first filter press of the concentrator is 0.1-0.5 wt%. Solid-liquid separation is performed using the first filter press, with an average filtration speed of 0.2-0.9 m / s² per square meter. 3 / m 2 ·h -1 .

[0070] In the above process, the pipe connecting the bottom of the fourth leaching tank to the first pump is a filter residue pipe. The filter residue pipe opening is 0.1-3.0m from the bottom of the tank. The filter residue is pumped to a horizontal screw centrifuge to achieve solid-liquid separation. The filtration and classification particle size is >10μm, and the flow rate is 5-10wt% of the liquid production (manganese sulfate solution). Particles smaller than 10μm are returned to the third leaching tank along with the filtrate as seed crystals required for Fe(OH)3 and Al(OH)3 precipitation.

[0071] In the above process, the heavy metal removal process involves adding a sulfiding agent to the first purification tank. The sulfiding agent used is at least one of barium sulfide, manganese sulfide, and sodium hydrosulfide. The amount of the sulfiding agent is 1.0-3.0 times the theoretical amount. The reaction time is 0.1-1 h, the reaction temperature is 80-90 ℃, and the stirring intensity is 15-50 r / min.

[0072] In the above process, the distance between the first discharge port of the fifth leaching tank and the bottom of the fifth leaching tank is 0.1-2.0m. The pipe connecting it to the second purification tank is a seed crystal circulation pipe. The sulfide heavy metal seed crystals are transported to the second purification tank as seed crystals through the third pump. The transport amount is 5-30wt% of the liquid preparation amount (manganese sulfate solution) and the solid content is 1-5wt%.

[0073] In the above process, the second discharge port of the fifth leaching tank is located in the middle of the fifth leaching tank (excluding heavy weight supernatant). The solid content of the (excluding heavy weight supernatant) in the pipe connected to the second discharge port is 0.1-3wt%. The excluding heavy weight supernatant enters the second filter press through the second discharge port for solid-liquid separation. The average filtration speed of the second filter press is 0.1-0.5m / m². 3 / m 2 ·h -1 .

[0074] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A continuous production system for qualified electrolytic manganese dioxide solution, characterized in that, The system includes, from front to back, a first leaching tank, a second leaching tank, a third leaching tank, a fourth leaching tank, a first neutralization tank, a second neutralization tank, a concentrator, a first purification tank, a second purification tank, a third purification tank, a fourth purification tank, and a fifth purification tank; except for the fifth purification tank, the upper end of the side wall of the tank closest to the next tank in each of the other tanks is provided with an overflow outlet; except for the first leaching tank and the first purification tank, the upper end of the side wall of the tank closest to the previous tank in each of the other tanks is provided with an overflow inlet; the overflow outlet of the previous tank and the overflow inlet of the next tank are connected by a pipe. The overflow outlet of the second neutralization tank is connected to the upper side wall of the concentrator via a pipe; the bottom of the fourth leaching tank is sequentially connected to a first pump and a horizontal screw centrifuge, the bottom of the concentrator is connected to a second pump, and the horizontal screw centrifuge and the second pump are respectively connected to the third leaching tank; the bottom of the side wall of the fifth purification tank is provided with a first discharge port, and the lower side wall of the fifth purification tank is provided with a second discharge port; the first discharge port is connected to the second purification tank via a third pump, and the second discharge port is connected to a second filter press via a pipe.

2. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, Each tank has turbulence columns on its inner wall.

3. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, An overflow pipe is installed at the overflow outlet in the tank.

4. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, The third leaching tank is provided with a feeding port above it, and the horizontal screw centrifuge and the second pump are respectively connected to the feeding port of the third leaching tank through pipes.

5. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, The first purification tank is provided with a feeding port at the top, and the concentrator is connected to the feeding port of the first purification tank through a first filter press.

6. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, The height difference between the first discharge port and the second discharge port is 3.0m.

7. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, A feeding port is provided above the first leaching tank / first neutralization tank.

8. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, The second purification tank is provided with a feeding port at the top, and the first discharge port is connected to the feeding port of the second purification tank.

9. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, The pipe connecting the bottom of the fourth leaching tank to the first pump is a filter residue pipe.

10. The continuous production system for qualified electrolytic manganese dioxide solution according to claim 1, characterized in that, The first leaching tank, the second leaching tank, the third leaching tank, the fourth leaching tank, the first neutralization tank, the second neutralization tank, the first purification tank, the second purification tank, the third purification tank, the fourth purification tank, and the fifth purification tank are all equipped with stirring paddles, which are connected to stirring pumps at the top of the tanks.

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