A solidification system for manganese slag and red mud

Abstract

This utility model discloses a solidification system for manganese slag and red mud, including a manganese slag pretreatment system, a red mud pretreatment system, a primary reaction system, a secondary reaction system, and a recovery system. The pretreatment system and the red mud pretreatment system are connected to the primary reaction system, the secondary reaction system is connected to the primary reaction system, and the recovery system is connected to the secondary reaction system. The manganese slag pretreatment system includes a water washing device and a water filter; the red mud pretreatment system includes a filter press; the primary reaction system includes a primary reaction tank, a settling cylinder, and an ammonia storage tank; the secondary reaction system includes a secondary reaction tank; and the recovery system includes a filtration and screening device, a magnetic separation device, a centrifugal separation device, and a receiving tray. This design, through the two reaction systems and the recovery system, generates hydrated calcium silicate gel, ettringite, and other substrates with higher utilization rates and value, thereby improving the overall utilization rate of the solidified products of manganese slag and red mud.

Description

Technical Field

[0001] This utility model relates to the field of manganese slag treatment technology, and in particular to a solidification system for manganese slag and red mud. Background Technology

[0002] Manganese slag is a solid waste generated during the electrolytic production of manganese. Its main components are calcium sulfate, silicon dioxide, and alumina, and it contains high concentrations of soluble heavy metals (such as manganese, lead, cadmium, zinc, and chromium) and ammonia nitrogen. When manganese slag is stored in the open, rainwater washes it away, causing soluble manganese (divalent manganese ions), ammonia nitrogen (ammonia ions -N), and heavy metals to seep into groundwater and surface water. This results in severely excessive concentrations of manganese leaching and ammonia nitrogen, leading to soil acidification, structural damage, and inhibition of plant absorption of calcium and magnesium, causing crop yield reduction and heavy metal accumulation. Manganese can enter the human body through polluted water sources or the food chain, and excessive accumulation in the brain can cause chronic manganese poisoning. The soluble salt content in manganese slag exceeds 5%, far exceeding landfill standards, therefore requiring special treatment for safe disposal.

[0003] The co-solidification technology of manganese slag and red mud can significantly improve the solidification rate of manganese / ammonia nitrogen, thereby blocking the migration of heavy metals and preventing environmental damage. Red mud can replace other solidification materials, reducing the cost of manganese slag treatment. However, in existing technologies, the products after solidification of manganese slag and red mud are not further extracted, which limits and restricts the reuse of solidified products, preventing them from being fully utilized. Therefore, a manganese slag and red mud solidification system is needed to further process and classify the solidified products to form a substrate with higher utilization rate, thereby improving the overall utilization rate of manganese slag and red mud solidified products. Utility Model Content

[0004] This utility model addresses the technical problem that the products of solidification of manganese slag and red mud cannot be further extracted and reused. It provides a solidification system for manganese slag and red mud, including a manganese slag pretreatment system, a red mud pretreatment system, a primary reaction system, a secondary reaction system, and a recovery system. The pretreatment system and the red mud pretreatment system are connected to the primary reaction system, the secondary reaction system is connected to the primary reaction system, and the recovery system is connected to the secondary reaction system.

[0005] The manganese slag pretreatment system includes: a water washing device and a water filter, wherein the water washing device is connected to the water filter;

[0006] The red mud pretreatment system includes a filter press device;

[0007] The primary reaction system includes: a primary reaction tank, a settling cylinder, and an ammonia storage tank. The settling cylinder is connected to the primary reaction tank, and the ammonia storage tank is connected to both the primary reaction tank and the settling cylinder.

[0008] The secondary reaction system includes a secondary reaction tank;

[0009] The recycling system includes a filtration and screening device, a magnetic separation device, a centrifugal separation device, and a receiving tray. The magnetic separation device is connected to the filtration and screening device, the centrifugal separation device is connected to the magnetic separation device, and the receiving tray is connected to the centrifugal separation device.

[0010] Preferably, in the above technical solution, the primary reaction vessel is provided with a first stirring device, and the first stirring device is provided with a cutting blade.

[0011] Preferably, in the above technical solution, the upper part of the primary reaction vessel is provided with a first dosing window.

[0012] Preferably, in the above technical solution, the ammonia storage tank is connected to the primary reaction tank and the settling cylinder respectively through pipelines.

[0013] Preferably, in the above technical solution, the settling cylinder is vertically located below the primary reaction vessel.

[0014] Preferably, in the above technical solution, the secondary reaction tank is equipped with a second stirring device.

[0015] Preferably, in the above technical solution, the upper part of the secondary reaction vessel is provided with a second dosing window.

[0016] Preferably, in the above technical solution, the receiving tray is provided with multiple material loading areas, which are isolated from each other.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] This invention features a primary reaction system that co-solidifies manganese slag and red mud. The hydroxide ions in the red mud neutralize the acidity of the manganese slag, causing divalent manganese ions to convert into manganese hydroxide precipitate, which is then further oxidized to stable manganese dioxide. Ammonium ions are converted into ammonia gas in an alkaline environment and released for recovery, achieving simultaneous manganese solidification and ammonia removal. The solidified alumina, iron oxide, and calcium sulfate continue to react in a secondary reaction system under the catalysis of an activator, further generating building materials and roadbed stabilized soil with higher utilization value. Through filtration, magnetic separation, and centrifugal separation devices in the recovery system, manganese dioxide, ettringite, hydrated calcium silicate, and manganese aluminum silicate are successively separated to obtain substrates with higher utilization rates and value, improving the overall utilization rate of the manganese slag and red mud co-solidification products. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the solidification system of manganese slag and red mud according to the present invention;

[0020] Figure 2 This is a process flow diagram of a solidification system for manganese slag and red mud according to the present invention.

[0021] Explanation of key figure labels:

[0022] 1-Washing device, 2-Water controller, 3-Filter press device, 4-Primary reaction tank, 5-Ammonia storage tank, 6-Settling cylinder, 7-Secondary reaction tank, 8-Filtering and screening device, 9-Magnetic separation device, 10-Centrifugation device, 11-Receiving tray, 41-First stirring device, 42-First dosing window, 71-Second stirring device, 72-Second dosing window. Detailed Implementation

[0023] 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.

[0024] like Figures 1-2 As shown, this utility model discloses a solidification system for manganese slag and red mud, comprising a manganese slag pretreatment system, a red mud pretreatment system, a primary reaction system, a secondary reaction system, and a recovery system. The pretreatment system and the red mud pretreatment system are connected to the primary reaction system, the secondary reaction system is connected to the primary reaction system, and the recovery system is connected to the secondary reaction system. The manganese slag pretreatment system includes a water washing device 1 and a water filter 2, with the water washing device 1 connected to the water filter 2. The water washing device 1 removes soluble divalent manganese ions and ammonium ions from the electrolytic manganese slag through water washing and ammonium salt precipitation, performing preliminary recovery of manganese / ammonia nitrogen from the manganese slag. Then, the water filter 2 adjusts the moisture content of the manganese slag, controlling it to 20-28% to avoid excessive moisture affecting the mixing and reaction efficiency. The red mud pretreatment system includes a filter press 3. Fresh red mud has a nearly 30% higher solidification rate for manganese ions compared to aged red mud. In this embodiment, the fresh red mud is dehydrated by the filter press 3. On the one hand, its moisture content is controlled at 25-35%, reducing the corrosiveness of alkaline liquids. On the other hand, the particle size of the red mud is controlled at 50-120 mesh, thereby increasing the specific surface area and promoting a full reaction.

[0025] In this embodiment, the primary reaction system includes: a primary reaction tank 4, a settling cylinder 6, and an ammonia storage tank 5. The settling cylinder 6 is connected to the primary reaction tank 4, and the ammonia storage tank 5 is connected to both the primary reaction tank 4 and the settling cylinder 6 via pipes. The settling cylinder 6 is vertically located below the primary reaction tank 4. The primary reaction tank 4 is equipped with a first stirring device 41, which has a cutting blade 43. The first stirring device 41 can make the mixture more uniform through stirring, and the rotating cutting blade 43 can chop up the lumpy manganese slag, resulting in more complete reaction of the granular manganese slag. The primary reaction tank 4 has a first dosing window 42 at its upper part. The fresh red mud and manganese slag in the primary reaction tank 4 react together. The electrolytic manganese slag is acidic, containing a high concentration of soluble divalent manganese ions and ammonium ions, while the red mud is strongly alkaline, containing free alkali (hydroxyl ions) and bound alkali, providing a stable source of hydroxide ions. The hydroxide ions in red mud neutralize the acidity of manganese slag, promoting the conversion of divalent manganese ions into manganese hydroxide precipitate, which is further oxidized into stable manganese dioxide. Ammonium ions are converted into ammonia gas under alkaline conditions, which is then released and recovered, achieving simultaneous manganese fixation and ammonia removal. A certain amount of dispersant and heavy metal stabilizer can be added through the first dosing window 42. The dispersant reduces the surface tension of the manganese slag, breaking up particle agglomeration and ensuring uniform mixing. During the settling stage, the dispersant continues to exert its steric hindrance effect, preventing particles from re-aggregating due to van der Waals forces and ensuring full contact at the reaction interface. The amino and hydroxyl functional groups in the heavy metal stabilizer provide lone pairs of electrons, forming stable chelates with heavy metal ions such as divalent manganese ions and hexavalent chromium ions, blocking their migration.

[0026] In this embodiment, the secondary reaction system includes a secondary reaction tank 7; the secondary reaction tank 7 is equipped with a second stirring device 71. The upper part of the secondary reaction tank 7 is provided with a second dosing window 72. The products of the above reaction are added into the secondary reaction tank 7, and appropriate amounts of quicklime, phosphogypsum, silica-alumina modifier, and water are added through the second dosing window 72, causing the alumina / iron oxide in the red mud to react with the calcium sulfate in the manganese slag to form ettringite (AFt). The Ca in the mixture... 2+ It reacts with SiO2 to form hydrated calcium silicate (CSH), and the residual divalent manganese ions in the mixture react with Si / Al minerals to form manganese aluminum silicate.

[0027] The recycling system includes a filtration and screening device 8, a magnetic separator 9, a centrifugal separator 10, and a receiving tray 11. The magnetic separator 9 is connected to the filtration and screening device 8, the centrifugal separator 10 is connected to the magnetic separator 9, and the receiving tray 11 is connected to the centrifugal separator 10. The receiving tray 11 has multiple material-carrying zones that are isolated from each other. Divalent manganese ions preferentially form manganese hydroxide, which is converted into high-density manganese dioxide in the air. Manganese dioxide is weakly magnetic and can be efficiently separated by the magnetic separator 9. Eettsonite is needle-shaped with a length of 1–10 μm and can be successfully separated by the filtration and screening device 8 using a 20 μm sieve. The centrifugal separator 10 uses centrifugation-assisted ultracentrifugation (10,000 rpm) to cause the hydrated calcium silicate gel to settle, thereby extracting the hydrated calcium silicate gel. The remaining compound is a manganese aluminum silicate mixture. The various extracted substances are classified and collected by the receiving tray 11 for later use in different scenarios and needs. Manganese dioxide adsorbs Pb through a tunnel structure. 2+ Cd 2+ It is used in mine wastewater treatment, catalyzing the generation of hydroxyl radicals from H2O2 to degrade dye wastewater. Erythrite can act as a cement expansion agent to compensate for concrete shrinkage and prevent cracking. When synergistically combined with hydrated calcium silicate gel, it can improve early compressive strength. Hydrated calcium silicate gel can also be used as a nanocrystalline seed early strength agent, mixed with cement to accelerate cement hydration and rapidly increase strength. Furthermore, hydrated calcium silicate gel interacts with interlayer Ca... 2+ With PO4 3- Hydroxyapatite is generated and used for the treatment of phosphorus-rich wastewater. Manganese aluminum silicates, utilizing their properties, can be widely used in refractory materials, corrosion-resistant alloys, and other fields.

[0028] This invention's primary reaction system co-solidifies manganese slag and red mud, neutralizing the acidity of the manganese slag with hydroxide ions from the red mud, causing divalent manganese ions to convert into manganese hydroxide precipitate, which is further oxidized to stable manganese dioxide. Ammonium ions are converted into ammonia gas in an alkaline environment and released for recovery, achieving simultaneous manganese solidification and ammonia removal. The solidified alumina, iron oxide, and calcium sulfate continue to react in a secondary reaction system under the catalysis of an activator, further generating building substrates and roadbed stabilized soils with higher utilization value. Through filtration, magnetic separation, and centrifugal separation devices in the recovery system, manganese dioxide, ettringite, hydrated calcium silicate gel, and manganese aluminum silicate are successively separated. The solidification system employed in this invention generates and separates solidified products to obtain substrates with higher utilization rates and value, improving the overall utilization rate of the manganese slag and red mud co-solidification products.

[0029] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A solidification system for manganese slag and red mud, characterized in that: It includes a manganese slag pretreatment system, a red mud pretreatment system, a primary reaction system, a secondary reaction system, and a recovery system. The pretreatment system and the red mud pretreatment system are connected to the primary reaction system, the secondary reaction system is connected to the primary reaction system, and the recovery system is connected to the secondary reaction system. The manganese slag pretreatment system includes: a water washing device (1) and a water filter (2), wherein the water washing device (1) is connected to the water filter (2); The red mud pretreatment system includes a filter press (3); The primary reaction system includes: a primary reaction tank (4), a settling cylinder (6) and an ammonia storage tank (5). The settling cylinder (6) is connected to the primary reaction tank (4), and the ammonia storage tank (5) is connected to both the primary reaction tank (4) and the settling cylinder (6). The secondary reaction system includes a secondary reaction vessel (7). The recycling system includes: a filtration and screening device (8), a magnetic separation device (9), a centrifugal separation device (10), and a receiving tray (11). The magnetic separation device (9) is connected to the filtration and screening device (8), the centrifugal separation device (10) is connected to the magnetic separation device (9), and the receiving tray (11) is connected to the centrifugal separation device (10).

2. The solidification system of manganese residue in conjunction with red mud according to claim 1, characterized by: The primary reaction vessel (4) is equipped with a first stirring device (41), and the first stirring device (41) is equipped with a cutting blade (43).

3. The solidification system of manganese slag in conjunction with red mud according to claim 1, characterized by: The primary reaction vessel (4) is provided with a first dosing window (42) at the top.

4. The solidification system of manganese slag in conjunction with red mud according to claim 1, characterized by: The ammonia storage tank (5) is connected to the primary reaction tank (4) and the settling cylinder (6) via pipelines.

5. The solidification system of manganese slag in conjunction with red mud according to claim 4, characterized by: The settling cylinder (6) is located vertically below the primary reaction vessel (4).

6. The solidification system of manganese slag in conjunction with red mud according to claim 1, characterized by: The secondary reaction vessel (7) is equipped with a second stirring device (71).

7. The solidification system of manganese slag in conjunction with red mud according to claim 1, characterized by: The secondary reaction vessel (7) is provided with a second dosing window (72) at the top.

8. The solidification system of manganese slag in conjunction with red mud according to claim 1, characterized by: The receiving tray (11) is provided with multiple material loading areas, which are isolated from each other.

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